/src/haproxy/src/http_ana.c

Source
/*
 * HTTP protocol analyzer
 *
 * Copyright (C) 2018 HAProxy Technologies, Christopher Faulet <cfaulet@haproxy.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *
 */

#include <haproxy/acl.h>
#include <haproxy/action-t.h>
#include <haproxy/api.h>
#include <haproxy/applet.h>
#include <haproxy/backend.h>
#include <haproxy/base64.h>
#include <haproxy/capture-t.h>
#include <haproxy/cfgparse.h>
#include <haproxy/channel.h>
#include <haproxy/check.h>
#include <haproxy/connection.h>
#include <haproxy/errors.h>
#include <haproxy/filters.h>
#include <haproxy/http.h>
#include <haproxy/http_ana.h>
#include <haproxy/http_htx.h>
#include <haproxy/http_ext.h>
#include <haproxy/htx.h>
#include <haproxy/log.h>
#include <haproxy/net_helper.h>
#include <haproxy/proxy.h>
#include <haproxy/regex.h>
#include <haproxy/sc_strm.h>
#include <haproxy/server-t.h>
#include <haproxy/stats.h>
#include <haproxy/stats-html.h>
#include <haproxy/stconn.h>
#include <haproxy/stream.h>
#include <haproxy/trace.h>
#include <haproxy/uri_auth-t.h>
#include <haproxy/vars.h>


#define TRACE_SOURCE &trace_strm

extern const char *stat_status_codes[];

struct pool_head *pool_head_requri __read_mostly = NULL;
struct pool_head *pool_head_capture __read_mostly = NULL;


static void http_end_request(struct stream *s);
static void http_end_response(struct stream *s);

static void http_capture_headers(struct htx *htx, char **cap, struct cap_hdr *cap_hdr);
static int http_del_hdr_value(char *start, char *end, char **from, char *next);
static size_t http_fmt_req_line(const struct htx_sl *sl, char *str, size_t len);
static void http_debug_stline(const char *dir, struct stream *s, const struct htx_sl *sl);
static void http_debug_hdr(const char *dir, struct stream *s, const struct ist n, const struct ist v);

static enum rule_result http_req_get_intercept_rule(struct proxy *px, struct list *def_rules, struct list *rules, struct stream *s);
static enum rule_result http_res_get_intercept_rule(struct proxy *px, struct list *def_rules, struct list *rules, struct stream *s, uint8_t final);
static enum rule_result http_req_restrict_header_names(struct stream *s, struct htx *htx, struct proxy *px);

static void http_manage_client_side_cookies(struct stream *s, struct channel *req);
static void http_manage_server_side_cookies(struct stream *s, struct channel *res);

static int http_stats_check_uri(struct stream *s, struct http_txn *txn, struct proxy *px);
static int http_handle_stats(struct stream *s, struct channel *req, struct proxy *px);

static int http_handle_expect_hdr(struct stream *s, struct htx *htx, struct http_msg *msg);
static int http_reply_100_continue(struct stream *s);

/* This stream analyser waits for a complete HTTP request. It returns 1 if the
 * processing can continue on next analysers, or zero if it either needs more
 * data or wants to immediately abort the request (eg: timeout, error, ...). It
 * is tied to AN_REQ_WAIT_HTTP and may may remove itself from s->req.analysers
 * when it has nothing left to do, and may remove any analyser when it wants to
 * abort.
 */
int http_wait_for_request(struct stream *s, struct channel *req, int an_bit)
{
  uint8_t do_log = 0;

  /*
   * We will analyze a complete HTTP request to check the its syntax.
   *
   * Once the start line and all headers are received, we may perform a
   * capture of the error (if any), and we will set a few fields. We also
   * check for monitor-uri, logging and finally headers capture.
   */
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct http_msg *msg = &txn->req;
  struct htx *htx;
  struct htx_sl *sl;
  char http_ver;

  DBG_TRACE_ENTER(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn, msg);

  if (unlikely(!IS_HTX_STRM(s))) {
    /* It is only possible when a TCP stream is upgrade to HTTP.
     * There is a transition period during which there is no
     * data. The stream is still in raw mode and SF_IGNORE flag is
     * still set. When this happens, the new mux is responsible to
     * handle all errors. Thus we may leave immediately.
     */
    BUG_ON(!(s->flags & SF_IGNORE) || !c_empty(&s->req));

    /* Don't connect for now */
    channel_dont_connect(req);

    /* An abort at this stage means we are performing a "destructive"
     * HTTP upgrade (TCP>H2). In this case, we can leave.
     */
    if (s->scf->flags & (SC_FL_ABRT_DONE|SC_FL_EOS)) {
      s->logs.logwait = 0;
                        s->logs.level = 0;
      stream_abort(s);
      req->analysers &= AN_REQ_FLT_END;
      req->analyse_exp = TICK_ETERNITY;
      DBG_TRACE_LEAVE(STRM_EV_STRM_ANA, s);
      return 1;
    }
    DBG_TRACE_LEAVE(STRM_EV_STRM_ANA, s);
    return 0;
  }

  htx = htxbuf(&req->buf);
  sl = http_get_stline(htx);
  if ((sl->flags & HTX_SL_F_NOT_HTTP) || HTX_SL_REQ_VLEN(sl) != 8) {
    /* Not an HTTP request */
    http_ver = 0;
    msg->vsn = 0;
  }
  else {
    char *ptr;

    ptr = HTX_SL_REQ_VPTR(sl);
    msg->vsn = ((ptr[5] - '0') << 4) + (ptr[7] - '0');
    http_ver = ptr[5] - '0';
  }

  /* Parsing errors are caught here */
  if (htx->flags & (HTX_FL_PARSING_ERROR|HTX_FL_PROCESSING_ERROR)) {
    stream_inc_http_req_ctr(s);
    proxy_inc_fe_req_ctr(sess->listener, sess->fe, http_ver);
    if (htx->flags & HTX_FL_PARSING_ERROR) {
      stream_inc_http_err_ctr(s);
      goto return_bad_req;
    }
    else
      goto return_int_err;
  }

  /* we're speaking HTTP here, so let's speak HTTP to the client */
  s->srv_error = http_return_srv_error;

  msg->msg_state = HTTP_MSG_BODY;
  stream_inc_http_req_ctr(s);
  proxy_inc_fe_req_ctr(sess->listener, sess->fe, http_ver); /* one more valid request for this FE */

  /* kill the pending keep-alive timeout */
  req->analyse_exp = TICK_ETERNITY;

  BUG_ON(htx_get_first_type(htx) != HTX_BLK_REQ_SL);

  /* 0: we might have to print this header in debug mode */
  if (unlikely((global.mode & MODE_DEBUG) &&
         (!(global.mode & MODE_QUIET) || (global.mode & MODE_VERBOSE)))) {
    int32_t pos;

    http_debug_stline("clireq", s, sl);

    for (pos = htx_get_first(htx); pos != -1; pos = htx_get_next(htx, pos)) {
      struct htx_blk *blk = htx_get_blk(htx, pos);
      enum htx_blk_type type = htx_get_blk_type(blk);

      if (type == HTX_BLK_EOH)
        break;
      if (type != HTX_BLK_HDR)
        continue;

      http_debug_hdr("clihdr", s,
               htx_get_blk_name(htx, blk),
               htx_get_blk_value(htx, blk));
    }
  }

  /*
   * 1: identify the method and the version. Also set HTTP flags
   */
  txn->meth = sl->info.req.meth;
  if (sl->flags & HTX_SL_F_VER_11)
                msg->flags |= HTTP_MSGF_VER_11;
  msg->flags |= HTTP_MSGF_XFER_LEN;
  if (sl->flags & HTX_SL_F_CLEN)
    msg->flags |= HTTP_MSGF_CNT_LEN;
  else if (sl->flags & HTX_SL_F_CHNK)
    msg->flags |= HTTP_MSGF_TE_CHNK;
  if (sl->flags & HTX_SL_F_BODYLESS)
    msg->flags |= HTTP_MSGF_BODYLESS;
  if (sl->flags & HTX_SL_F_CONN_UPG)
    msg->flags |= HTTP_MSGF_CONN_UPG;

  /* we can make use of server redirect on GET and HEAD */
  if (txn->meth == HTTP_METH_GET || txn->meth == HTTP_METH_HEAD)
    s->flags |= SF_REDIRECTABLE;
  else if (txn->meth == HTTP_METH_OTHER && isteqi(htx_sl_req_meth(sl), ist("PRI"))) {
    /* PRI is reserved for the HTTP/2 preface */
    goto return_bad_req;
  }

  /*
   * 2: check if the URI matches the monitor_uri.  We have to do this for
   * every request which gets in, because the monitor-uri is defined by
   * the frontend. If the monitor-uri starts with a '/', the matching is
   * done against the request's path. Otherwise, the request's uri is
   * used. It is a workaround to let HTTP/2 health-checks work as
   * expected.
   */
  if (unlikely(isttest(sess->fe->monitor_uri))) {
    const struct ist monitor_uri = sess->fe->monitor_uri;
    struct http_uri_parser parser = http_uri_parser_init(htx_sl_req_uri(sl));

    if ((istptr(monitor_uri)[0] == '/' &&
         isteq(http_parse_path(&parser), monitor_uri)) ||
        isteq(htx_sl_req_uri(sl), monitor_uri)) {
      /*
       * We have found the monitor URI
       */
      struct acl_cond *cond;

      s->flags |= SF_MONITOR;
      if (sess->fe_tgcounters)
        _HA_ATOMIC_INC(&sess->fe_tgcounters->intercepted_req);

      /* Check if we want to fail this monitor request or not */
      list_for_each_entry(cond, &sess->fe->mon_fail_cond, list) {
        if (!acl_match_cond(cond, sess->fe, sess, s, SMP_OPT_DIR_REQ|SMP_OPT_FINAL))
          continue;

        /* we fail this request, let's return 503 service unavail */
        txn->status = 503;
        if (!(s->flags & SF_ERR_MASK))
          s->flags |= SF_ERR_LOCAL; /* we don't want a real error here */
        stream_report_term_evt(s->scf, strm_tevt_type_intercepted);
        goto return_prx_cond;
      }

      /* nothing to fail, let's reply normally */
      txn->status = 200;
      if (!(s->flags & SF_ERR_MASK))
        s->flags |= SF_ERR_LOCAL; /* we don't want a real error here */
      stream_report_term_evt(s->scf, strm_tevt_type_intercepted);
      goto return_prx_cond;
    }
  }

  /*
   * 3: Maybe we have to copy the original REQURI for the logs ?
   * Note: we cannot log anymore if the request has been
   * classified as invalid.
   */
  if (unlikely(sess->fe->to_log == LW_LOGSTEPS)) {
    if (log_orig_proxy(LOG_ORIG_TXN_REQUEST, sess->fe))
      do_log = 1; /* forced log (through "log-steps") */
  }
  else if (unlikely(s->logs.logwait & LW_REQ)) {
    /* default behavior when log-steps isn't specified:
     * don't log systematically, but only if conditions are
     * met, ie: not log emitted yet for this txn, all data available
     * (unless "option logasap" is used)
     */
    do_log = 2;
  }

  if (do_log) {
    /* we have a complete HTTP request that we must log */
    if ((txn->uri = pool_alloc(pool_head_requri)) != NULL) {
      size_t len;

      len = http_fmt_req_line(sl, txn->uri, global.tune.requri_len - 1);
      txn->uri[len] = 0;

      if (do_log == 1 || !(s->logs.logwait &= ~(LW_REQ|LW_INIT)))
        s->do_log(s, log_orig(LOG_ORIG_TXN_REQUEST, LOG_ORIG_FL_NONE));
    } else {
      ha_alert("HTTP logging : out of memory.\n");
    }
  }

  /* if the frontend has "option http-use-proxy-header", we'll check if
   * we have what looks like a proxied connection instead of a connection,
   * and in this case set the TX_USE_PX_CONN flag to use Proxy-connection.
   * Note that this is *not* RFC-compliant, however browsers and proxies
   * happen to do that despite being non-standard :-(
   * We consider that a request not beginning with either '/' or '*' is
   * a proxied connection, which covers both "scheme://location" and
   * CONNECT ip:port.
   */
  if ((sess->fe->options2 & PR_O2_USE_PXHDR) &&
      *HTX_SL_REQ_UPTR(sl) != '/' && *HTX_SL_REQ_UPTR(sl) != '*')
    txn->flags |= TX_USE_PX_CONN;

  /* 5: we may need to capture headers */
  if (unlikely((s->logs.logwait & LW_REQHDR) && s->req_cap))
    http_capture_headers(htx, s->req_cap, sess->fe->req_cap);

  /* we may have to wait for the request's body */
  if (s->be->options & PR_O_WREQ_BODY)
    req->analysers |= AN_REQ_HTTP_BODY;

  /*
   * RFC7234#4:
   *   A cache MUST write through requests with methods
   *   that are unsafe (Section 4.2.1 of [RFC7231]) to
   *   the origin server; i.e., a cache is not allowed
   *   to generate a reply to such a request before
   *   having forwarded the request and having received
   *   a corresponding response.
   *
   * RFC7231#4.2.1:
   *   Of the request methods defined by this
   *   specification, the GET, HEAD, OPTIONS, and TRACE
   *   methods are defined to be safe.
   */
  if (likely(txn->meth == HTTP_METH_GET ||
       txn->meth == HTTP_METH_HEAD ||
       txn->meth == HTTP_METH_OPTIONS ||
       txn->meth == HTTP_METH_TRACE))
    txn->flags |= TX_CACHEABLE | TX_CACHE_COOK;

  /* end of job, return OK */
  req->analysers &= ~an_bit;
  req->analyse_exp = TICK_ETERNITY;

  DBG_TRACE_LEAVE(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 1;

 return_int_err:
  txn->status = 500;
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_INTERNAL;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->internal_errors);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->internal_errors);
  stream_report_term_evt(s->scf, strm_tevt_type_internal_err);
  goto return_prx_cond;

 return_bad_req:
  txn->status = 400;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->failed_req);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->failed_req);
  stream_report_term_evt(s->scf, strm_tevt_type_proto_err);
  /* fall through */

 return_prx_cond:
  http_set_term_flags(s);
  http_reply_and_close(s, txn->status, http_error_message(s));

  DBG_TRACE_DEVEL("leaving on error",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
  return 0;
}


/* This stream analyser runs all HTTP request processing which is common to
 * frontends and backends, which means blocking ACLs, filters, connection-close,
 * reqadd, stats and redirects. This is performed for the designated proxy.
 * It returns 1 if the processing can continue on next analysers, or zero if it
 * either needs more data or wants to immediately abort the request (eg: deny,
 * error, ...).
 */
int http_process_req_common(struct stream *s, struct channel *req, int an_bit, struct proxy *px)
{
  struct list *def_rules, *rules;
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct http_msg *msg = &txn->req;
  struct htx *htx;
  struct redirect_rule *rule;
  enum rule_result verdict;
  struct connection *conn = objt_conn(sess->origin);
  int stats_rules = 0;

  DBG_TRACE_ENTER(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn, msg);

  htx = htxbuf(&req->buf);

  /* just in case we have some per-backend tracking. Only called the first
   * execution of the analyser. */
  if (!s->current_rule && !s->current_rule_list)
    stream_inc_be_http_req_ctr(s);

  def_rules = ((px->defpx && (an_bit == AN_REQ_HTTP_PROCESS_FE || px != sess->fe)) ? &px->defpx->http_req_rules : NULL);
  rules = &px->http_req_rules;

  verdict = HTTP_RULE_RES_CONT;

  if (px->uri_auth && s->current_rule_list == &px->uri_auth->http_req_rules)
    stats_rules = 1;

  /* resume stats http-request rules if needed */
  if (stats_rules)
    verdict = http_req_get_intercept_rule(px, NULL, &px->uri_auth->http_req_rules, s);
  /* evaluate http-request rules */
  else if ((def_rules && !LIST_ISEMPTY(def_rules)) || !LIST_ISEMPTY(rules))
    verdict = http_req_get_intercept_rule(px, def_rules, rules, s);

 rule_verdict:

  switch (verdict) {
    case HTTP_RULE_RES_YIELD: /* some data miss, call the function later. */
      goto return_prx_yield;

    case HTTP_RULE_RES_FYIELD: /* we must try again after context-switch */
      goto return_prx_fyield;

    case HTTP_RULE_RES_CONT:
    case HTTP_RULE_RES_STOP: /* nothing to do */
      break;

    case HTTP_RULE_RES_DENY: /* deny or tarpit */
      if (txn->flags & TX_CLTARPIT)
        goto tarpit;
      goto deny;

    case HTTP_RULE_RES_ABRT: /* abort request, response already sent. Eg: auth */
      stream_report_term_evt(s->scf, strm_tevt_type_intercepted);
      goto return_prx_cond;

    case HTTP_RULE_RES_DONE: /* OK, but terminate request processing (eg: redirect) */
      goto done;

    case HTTP_RULE_RES_BADREQ: /* failed with a bad request */
      goto return_bad_req;

    case HTTP_RULE_RES_ERROR: /* failed with a bad request */
      goto return_int_err;
  }

  if (stats_rules)
    goto resume_stats_rules;

  if (px->options2 & (PR_O2_RSTRICT_REQ_HDR_NAMES_BLK|PR_O2_RSTRICT_REQ_HDR_NAMES_DEL)) {
    verdict = http_req_restrict_header_names(s, htx, px);
    if (verdict == HTTP_RULE_RES_DENY)
      goto deny;
  }

  if (conn && (conn->flags & CO_FL_EARLY_DATA) &&
      (conn->flags & (CO_FL_EARLY_SSL_HS | CO_FL_SSL_WAIT_HS))) {
    struct http_hdr_ctx ctx;

    ctx.blk = NULL;
    if (!http_find_header(htx, ist("Early-Data"), &ctx, 0)) {
      if (unlikely(!http_add_header(htx, ist("Early-Data"), ist("1"), 0)))
        goto return_fail_rewrite;
    }
  }

  /* OK at this stage, we know that the request was accepted according to
   * the http-request rules, we can check for the stats. Note that the
   * URI is detected *before* the req* rules in order not to be affected
   * by a possible reqrep, while they are processed *after* so that a
   * reqdeny can still block them. This clearly needs to change in 1.6!
   */
  if (!s->target && http_stats_check_uri(s, txn, px)) {
    s->target = &http_stats_applet.obj_type;
    if (unlikely(!sc_applet_create(s->scb, objt_applet(s->target)))) {
      s->logs.request_ts = now_ns;
      if (!(s->flags & SF_ERR_MASK))
        s->flags |= SF_ERR_RESOURCE;
      goto return_int_err;
    }

    /* parse the whole stats request and extract the relevant information */
    http_handle_stats(s, req, px);
    verdict = http_req_get_intercept_rule(px, NULL, &px->uri_auth->http_req_rules, s);
    stats_rules = 1;
    goto rule_verdict;
  }

 resume_stats_rules:

  /* Proceed with the applets now. */
  if (unlikely(objt_applet(s->target))) {
    /* report it if the request was intercepted by the frontend */
    if (sess->fe == s->be && sess->fe_tgcounters)
      _HA_ATOMIC_INC(&sess->fe_tgcounters->intercepted_req);

    if (http_handle_expect_hdr(s, htx, msg) == -1)
      goto return_int_err;

    if (!(s->flags & SF_ERR_MASK))      // this is not really an error but it is
      s->flags |= SF_ERR_LOCAL;   // to mark that it comes from the proxy
    http_set_term_flags(s);

    if (HAS_FILTERS(s))
      req->analysers |= AN_REQ_FLT_HTTP_HDRS;

    /* enable the minimally required analyzers to handle keep-alive and compression on the HTTP response */
    req->analysers &= (AN_REQ_HTTP_BODY | AN_REQ_FLT_HTTP_HDRS | AN_REQ_FLT_END);
    req->analysers &= ~AN_REQ_FLT_XFER_DATA;
    req->analysers |= AN_REQ_HTTP_XFER_BODY;

    s->scb->flags |= SC_FL_SND_ASAP;
    s->flags |= SF_ASSIGNED;
    goto done;
  }

  /* check whether we have some ACLs set to redirect this request */
  list_for_each_entry(rule, &px->redirect_rules, list) {
    if (!acl_match_cond(rule->cond, px, sess, s, SMP_OPT_DIR_REQ|SMP_OPT_FINAL))
      continue;
    if (!http_apply_redirect_rule(rule, s, txn)) {
      goto return_int_err;
    }
    stream_report_term_evt(s->scf, strm_tevt_type_intercepted);
    goto done;
  }

  /* POST requests may be accompanied with an "Expect: 100-Continue" header.
   * If this happens, then the data will not come immediately, so we must
   * send all what we have without waiting. Note that due to the small gain
   * in waiting for the body of the request, it's easier to simply put the
   * SC_FL_SND_ASAP flag on the back SC any time. It's a one-shot flag so it
   * will remove itself once used.
   */
  s->scb->flags |= SC_FL_SND_ASAP;

 done: /* done with this analyser, continue with next ones that the calling
   * points will have set, if any.
   */
  req->analyse_exp = TICK_ETERNITY;
 done_without_exp: /* done with this analyser, but don't reset the analyse_exp. */
  req->analysers &= ~an_bit;
  s->current_rule = s->current_rule_list = NULL;
  DBG_TRACE_LEAVE(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 1;

 tarpit:
  /* Allow cookie logging
   */
  if (s->be->cookie_name || sess->fe->capture_name)
    http_manage_client_side_cookies(s, req);

  /* When a connection is tarpitted, we use the tarpit timeout,
   * which may be the same as the connect timeout if unspecified.
   * If unset, then set it to zero because we really want it to
   * eventually expire. We build the tarpit as an analyser.
   */
  channel_htx_erase(&s->req, htx);

  /* wipe the request out so that we can drop the connection early
   * if the client closes first.
   */
  channel_dont_connect(req);

  req->analysers &= AN_REQ_FLT_END; /* remove switching rules etc... */
  req->analysers |= AN_REQ_HTTP_TARPIT;
  req->analyse_exp = tick_add_ifset(now_ms, s->tarpit_timeout ? s->tarpit_timeout : s->be->timeout.tarpit);
  if (!req->analyse_exp)
    req->analyse_exp = tick_add(now_ms, 0);
  stream_inc_http_err_ctr(s);
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->denied_req);
  if ((s->flags & SF_BE_ASSIGNED) && s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->denied_req);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->denied_req);
  stream_report_term_evt(s->scf, strm_tevt_type_intercepted);
  goto done_without_exp;

 deny: /* this request was blocked (denied) */

  /* Allow cookie logging
   */
  if (s->be->cookie_name || sess->fe->capture_name)
    http_manage_client_side_cookies(s, req);

  s->logs.request_ts = now_ns;
  stream_inc_http_err_ctr(s);
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->denied_req);
  if ((s->flags & SF_BE_ASSIGNED) && s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->denied_req);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->denied_req);
  stream_report_term_evt(s->scf, strm_tevt_type_intercepted);
  goto return_prx_err;

 return_fail_rewrite:
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_PRXCOND;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->failed_rewrites);
  if ((s->flags & SF_BE_ASSIGNED) && s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->failed_rewrites);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->failed_rewrites);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->failed_rewrites);
  /* fall through */

 return_int_err:
  txn->status = 500;
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_INTERNAL;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->internal_errors);
  if ((s->flags & SF_BE_ASSIGNED) && s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->internal_errors);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->internal_errors);
  stream_report_term_evt(s->scf, strm_tevt_type_internal_err);
  goto return_prx_err;

 return_bad_req:
  txn->status = 400;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->failed_req);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->failed_req);
  stream_report_term_evt(s->scf, strm_tevt_type_proto_err);
  /* fall through */

 return_prx_err:
  http_set_term_flags(s);
  http_reply_and_close(s, txn->status, http_error_message(s));
  /* fall through */

 return_prx_cond:
  http_set_term_flags(s);
  req->analysers &= AN_REQ_FLT_END;
  req->analyse_exp = TICK_ETERNITY;
  s->current_rule = s->current_rule_list = NULL;
  DBG_TRACE_DEVEL("leaving on error",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
  return 0;

 return_prx_yield:
  channel_dont_connect(req);
  DBG_TRACE_DEVEL("waiting for more data",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;

 return_prx_fyield:
  channel_dont_connect(req);
  DBG_TRACE_DEVEL("forced yield",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;
}

/* This function performs all the processing enabled for the current request.
 * It returns 1 if the processing can continue on next analysers, or zero if it
 * needs more data, encounters an error, or wants to immediately abort the
 * request. It relies on buffers flags, and updates s->req.analysers.
 */
int http_process_request(struct stream *s, struct channel *req, int an_bit)
{
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct htx *htx;
  struct connection *cli_conn = objt_conn(strm_sess(s)->origin);

  DBG_TRACE_ENTER(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);

  /*
   * Right now, we know that we have processed the entire headers
   * and that unwanted requests have been filtered out. We can do
   * whatever we want with the remaining request. Also, now we
   * may have separate values for ->fe, ->be.
   */
  htx = htxbuf(&req->buf);

  /*
   * 7: Now we can work with the cookies.
   * Note that doing so might move headers in the request, but
   * the fields will stay coherent and the URI will not move.
   * This should only be performed in the backend.
   */
  if (s->be->cookie_name || sess->fe->capture_name)
    http_manage_client_side_cookies(s, req);

  /* 8: Generate unique ID if a "unique-id-format" is defined.
   *
   * A unique ID is generated even when it is not sent to ensure that the ID can make use of
   * fetches only available in the HTTP request processing stage.
   */
  if (!lf_expr_isempty(&sess->fe->format_unique_id)) {
    struct ist unique_id = stream_generate_unique_id(s, &sess->fe->format_unique_id);

    if (!isttest(unique_id)) {
      if (!(s->flags & SF_ERR_MASK))
        s->flags |= SF_ERR_RESOURCE;
      goto return_int_err;
    }

    /* send unique ID if a "unique-id-header" is defined */
    if (isttest(sess->fe->header_unique_id) &&
        unlikely(!http_add_header(htx, sess->fe->header_unique_id, unique_id, 1)))
        goto return_fail_rewrite;
  }

  /* handle http extensions (if configured) */
  if (unlikely(!http_handle_7239_header(s, req)))
    goto return_fail_rewrite;
  if (unlikely(!http_handle_xff_header(s, req)))
    goto return_fail_rewrite;
  if (unlikely(!http_handle_xot_header(s, req)))
    goto return_fail_rewrite;

  /* Filter the request headers if there are filters attached to the
   * stream.
   */
  if (HAS_FILTERS(s))
    req->analysers |= AN_REQ_FLT_HTTP_HDRS;

  /* If we have no server assigned yet and we're balancing on url_param
   * with a POST request, we may be interested in checking the body for
   * that parameter. This will be done in another analyser.
   */
  if (!(s->flags & (SF_ASSIGNED|SF_DIRECT)) &&
      s->txn.http->meth == HTTP_METH_POST &&
      (s->be->lbprm.algo & BE_LB_ALGO) == BE_LB_ALGO_PH) {
    channel_dont_connect(req);
    req->analysers |= AN_REQ_HTTP_BODY;
  }

  req->analysers &= ~AN_REQ_FLT_XFER_DATA;
  req->analysers |= AN_REQ_HTTP_XFER_BODY;

  /* We expect some data from the client. Unless we know for sure
   * we already have a full request, we have to re-enable quick-ack
   * in case we previously disabled it, otherwise we might cause
   * the client to delay further data.
   */
  if ((sess->listener && (sess->listener->bind_conf->options & BC_O_NOQUICKACK)) && !(htx->flags & HTX_FL_EOM))
    conn_set_quickack(cli_conn, 1);

  /*************************************************************
   * OK, that's finished for the headers. We have done what we *
   * could. Let's switch to the DATA state.                    *
   ************************************************************/
  req->analyse_exp = TICK_ETERNITY;
  req->analysers &= ~an_bit;

  s->logs.request_ts = now_ns;
  /* OK let's go on with the BODY now */
  DBG_TRACE_LEAVE(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 1;

 return_fail_rewrite:
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_PRXCOND;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->failed_rewrites);
  if ((s->flags & SF_BE_ASSIGNED) && s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->failed_rewrites);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->failed_rewrites);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->failed_rewrites);
  /* fall through */

 return_int_err:
  txn->status = 500;
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_INTERNAL;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->internal_errors);
  if ((s->flags & SF_BE_ASSIGNED) && s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->internal_errors);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->internal_errors);
  stream_report_term_evt(s->scf, strm_tevt_type_internal_err);

  http_set_term_flags(s);
  http_reply_and_close(s, txn->status, http_error_message(s));

  DBG_TRACE_DEVEL("leaving on error",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
  return 0;
}

/* This function is an analyser which processes the HTTP tarpit. It always
 * returns zero, at the beginning because it prevents any other processing
 * from occurring, and at the end because it terminates the request.
 */
int http_process_tarpit(struct stream *s, struct channel *req, int an_bit)
{
  struct http_txn *txn = s->txn.http;

  DBG_TRACE_ENTER(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn, &txn->req);
  /* This connection is being tarpitted. The CLIENT side has
   * already set the connect expiration date to the right
   * timeout. We just have to check that the client is still
   * there and that the timeout has not expired.
   */
  channel_dont_connect(req);
  if (!(s->scf->flags & (SC_FL_ABRT_DONE|SC_FL_EOS)) &&
      !tick_is_expired(req->analyse_exp, now_ms)) {
    /* Be sure to drain all data from the request channel */
    channel_htx_erase(req, htxbuf(&req->buf));
    DBG_TRACE_DEVEL("waiting for tarpit timeout expiry",
        STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
    return 0;
  }


  /* We will set the queue timer to the time spent, just for
   * logging purposes. We fake a 500 server error, so that the
   * attacker will not suspect his connection has been tarpitted.
   * It will not cause trouble to the logs because we can exclude
   * the tarpitted connections by filtering on the 'PT' status flags.
   */
  s->logs.t_queue = ns_to_ms(now_ns - s->logs.accept_ts);

  stream_report_term_evt(s->scf, strm_tevt_type_intercepted);
  http_set_term_flags(s);
  http_reply_and_close(s, txn->status, (!(s->scf->flags & SC_FL_ERROR) ? http_error_message(s) : NULL));

  DBG_TRACE_LEAVE(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;
}

/* This function is an analyser which waits for the HTTP request body. It waits
 * for either the buffer to be full, or the full advertised contents to have
 * reached the buffer. It must only be called after the standard HTTP request
 * processing has occurred, because it expects the request to be parsed and will
 * look for the Expect header. It may send a 100-Continue interim response. It
 * returns zero if it needs to read more data, or 1 once it has completed its
 * analysis.
 */
int http_wait_for_request_body(struct stream *s, struct channel *req, int an_bit)
{
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;

  DBG_TRACE_ENTER(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn,
      &s->txn.http->req);


  switch (http_wait_for_msg_body(s, req, s->be->timeout.httpreq, 0, 0)) {
  case HTTP_RULE_RES_CONT:
    s->waiting_entity.type = STRM_ENTITY_NONE;
    s->waiting_entity.ptr = NULL;
    goto http_end;
  case HTTP_RULE_RES_YIELD:
    s->waiting_entity.type = STRM_ENTITY_WREQ_BODY;
    s->waiting_entity.ptr = NULL;
    goto missing_data_or_waiting;
  case HTTP_RULE_RES_BADREQ:
    goto return_bad_req;
  case HTTP_RULE_RES_ERROR:
    goto return_int_err;
  case HTTP_RULE_RES_ABRT:
    stream_report_term_evt(s->scf, strm_tevt_type_intercepted);
    goto return_prx_cond;
  default:
    goto return_int_err;
  }

 http_end:
  /* The situation will not evolve, so let's give up on the analysis. */
  s->logs.request_ts = now_ns;  /* update the request timer to reflect full request */
  req->analysers &= ~an_bit;
  req->analyse_exp = TICK_ETERNITY;
  DBG_TRACE_LEAVE(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 1;

 missing_data_or_waiting:
  channel_dont_connect(req);
  DBG_TRACE_DEVEL("waiting for more data",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;

 return_int_err:
  txn->status = 500;
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_INTERNAL;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->internal_errors);
  if ((s->flags & SF_BE_ASSIGNED) && s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->internal_errors);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->internal_errors);
  stream_report_term_evt(s->scf, strm_tevt_type_internal_err);
  goto return_prx_err;

 return_bad_req: /* let's centralize all bad requests */
  txn->status = 400;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->failed_req);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->failed_req);
  stream_report_term_evt(s->scf, strm_tevt_type_proto_err);
  /* fall through */

 return_prx_err:
  http_set_term_flags(s);
  http_reply_and_close(s, txn->status, http_error_message(s));
  /* fall through */

 return_prx_cond:
  http_set_term_flags(s);

  req->analysers &= AN_REQ_FLT_END;
  req->analyse_exp = TICK_ETERNITY;
  DBG_TRACE_DEVEL("leaving on error",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
  return 0;
}

/* This function is an analyser which forwards request body (including chunk
 * sizes if any). It is called as soon as we must forward, even if we forward
 * zero byte. The only situation where it must not be called is when we're in
 * tunnel mode and we want to forward till the close. It's used both to forward
 * remaining data and to resync after end of body. It expects the msg_state to
 * be between MSG_BODY and MSG_DONE (inclusive). It returns zero if it needs to
 * read more data, or 1 once we can go on with next request or end the stream.
 * When in MSG_DATA or MSG_TRAILERS, it will automatically forward chunk_len
 * bytes of pending data + the headers if not already done.
 */
int http_request_forward_body(struct stream *s, struct channel *req, int an_bit)
{
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct http_msg *msg = &txn->req;
  struct htx *htx;
  short status = 0;
  int ret;

  DBG_TRACE_ENTER(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn, msg);

  htx = htxbuf(&req->buf);

  if (htx->flags & HTX_FL_PARSING_ERROR)
    goto return_bad_req;
  if (htx->flags & HTX_FL_PROCESSING_ERROR)
    goto return_int_err;

  /* Note that we don't have to send 100-continue back because we don't
   * need the data to complete our job, and it's up to the server to
   * decide whether to return 100, 417 or anything else in return of
   * an "Expect: 100-continue" header.
   */
  if (msg->msg_state == HTTP_MSG_BODY)
    msg->msg_state = HTTP_MSG_DATA;

  /* in most states, we should abort in case of early close */
  channel_auto_close(req);

  if (req->to_forward) {
    if (req->to_forward == CHN_INFINITE_FORWARD) {
      if (s->scf->flags & SC_FL_EOI)
        msg->msg_state = HTTP_MSG_ENDING;
    }
    else {
      /* We can't process the buffer's contents yet */
      req->flags |= CF_WAKE_WRITE;
      goto missing_data_or_waiting;
    }
  }

  if (msg->msg_state >= HTTP_MSG_ENDING)
    goto ending;

  if (txn->meth == HTTP_METH_CONNECT) {
    msg->msg_state = HTTP_MSG_ENDING;
    goto ending;
  }

  /* Forward input data. We get it by removing all outgoing data not
   * forwarded yet from HTX data size. If there are some data filters, we
   * let them decide the amount of data to forward.
   */
  if (HAS_REQ_DATA_FILTERS(s)) {
    ret  = flt_http_payload(s, msg, htx->data);
    if (ret < 0)
      goto return_bad_req;
    c_adv(req, ret);
  }
  else {
    c_adv(req, htx->data - co_data(req));
    if ((global.tune.options & GTUNE_USE_FAST_FWD) && (msg->flags & HTTP_MSGF_XFER_LEN) &&
        (!(msg->flags & HTTP_MSGF_CONN_UPG) || (htx->flags & HTX_FL_EOM)))
      channel_htx_forward_forever(req, htx);
  }

  if (htx->data != co_data(req))
    goto missing_data_or_waiting;

  /* Check if the end-of-message is reached and if so, switch the message
   * in HTTP_MSG_ENDING state. Then if all data was marked to be
   * forwarded, set the state to HTTP_MSG_DONE.
   */
  if (!(htx->flags & HTX_FL_EOM))
    goto missing_data_or_waiting;

  msg->msg_state = HTTP_MSG_ENDING;

  ending:
  s->scb->flags &= ~SC_FL_SND_EXP_MORE; /* no more data are expected to be send */

  /* other states, ENDING...TUNNEL */
  if (msg->msg_state >= HTTP_MSG_DONE)
    goto done;

  if (HAS_REQ_DATA_FILTERS(s)) {
    ret = flt_http_end(s, msg);
    if (ret <= 0) {
      if (!ret)
        goto missing_data_or_waiting;
      goto return_bad_req;
    }
  }

  if (txn->meth == HTTP_METH_CONNECT)
    msg->msg_state = HTTP_MSG_TUNNEL;
  else {
    msg->msg_state = HTTP_MSG_DONE;
    req->to_forward = 0;
  }

  done:
  /* we don't want to forward closes on DONE except in tunnel mode. */
  if (!(txn->flags & TX_CON_WANT_TUN))
    channel_dont_close(req);

  if ((s->scb->flags & SC_FL_SHUT_DONE) && co_data(req)) {
    /* request errors are most likely due to the server aborting the
     * transfer. But handle server aborts only if the response was
     * not received yet. Otherwise, let the response analyzer the
     * responsibility to handle the error. It is especially
     * important to properly handle L7-retries but also K/A silent close.
     */
    if (txn->rsp.msg_state >= HTTP_MSG_BODY && htx_is_empty(htxbuf(&s->res.buf)))
      goto return_srv_abort;
  }

  http_end_request(s);
  if (!(req->analysers & an_bit)) {
    DBG_TRACE_LEAVE(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
    return 1;
  }

  /* If "option abortonclose" is set on the backend, we want to monitor
   * the client's connection and forward any shutdown notification to the
   * server, which will decide whether to close or to go on processing the
   * request. We only do that in tunnel mode, and not in other modes since
   * it can be abused to exhaust source ports. */
  if (proxy_abrt_close_def(s->be, 1)) {
    channel_auto_read(req);
    if ((s->scf->flags & (SC_FL_ABRT_DONE|SC_FL_EOS)) && !(txn->flags & TX_CON_WANT_TUN))
      s->scb->flags |= SC_FL_NOLINGER;
    channel_auto_close(req);
  }
  else if (s->txn.http->meth == HTTP_METH_POST) {
    /* POST requests may require to read extra CRLF sent by broken
     * browsers and which could cause an RST to be sent upon close
     * on some systems (eg: Linux). */
    channel_auto_read(req);
  }
  DBG_TRACE_DEVEL("waiting for the end of the HTTP txn",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;

 missing_data_or_waiting:
  /* stop waiting for data if the input is closed before the end */
  if (msg->msg_state < HTTP_MSG_ENDING && (s->scf->flags & (SC_FL_ABRT_DONE|SC_FL_EOS)))
    goto return_cli_abort;

 waiting:
  /* waiting for the last bits to leave the buffer */
  if (s->scb->flags & SC_FL_SHUT_DONE) {
    /* Handle server aborts only if the response was not received
     * yet. Otherwise, let the response analyzer the responsibility
     * to handle the error. It is especially important to properly
     * handle L7-retries but also K/A silent close.
     */
    if (txn->rsp.msg_state >= HTTP_MSG_BODY && htx_is_empty(htxbuf(&s->res.buf)))
      goto return_srv_abort;
  }

  /* When TE: chunked is used, we need to get there again to parse remaining
   * chunks even if the client has closed, so we don't want to set CF_DONTCLOSE.
   * And when content-length is used, we never want to let the possible
   * shutdown be forwarded to the other side, as the state machine will
   * take care of it once the client responds. It's also important to
   * prevent TIME_WAITs from accumulating on the backend side, and for
   * HTTP/2 where the last frame comes with a shutdown.
   */
  if (msg->flags & HTTP_MSGF_XFER_LEN)
    channel_dont_close(req);

  /* We know that more data are expected, but we couldn't send more that
   * what we did. So we always set the SC_FL_SND_EXP_MORE flag so that the
   * system knows it must not set a PUSH on this first part. Interactive
   * modes are already handled by the stream sock layer. We must not do
   * this in content-length mode because it could present the MSG_MORE
   * flag with the last block of forwarded data, which would cause an
   * additional delay to be observed by the receiver.
   */
  if (HAS_REQ_DATA_FILTERS(s))
    s->scb->flags |= SC_FL_SND_EXP_MORE;

  DBG_TRACE_DEVEL("waiting for more data to forward",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;

  return_cli_abort:
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->cli_aborts);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->cli_aborts);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->cli_aborts);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->cli_aborts);
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= ((req->flags & CF_READ_TIMEOUT) ? SF_ERR_CLITO : SF_ERR_CLICL);
  status = 400;
  goto return_prx_cond;

  return_srv_abort:
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->srv_aborts);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->srv_aborts);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->srv_aborts);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->srv_aborts);
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= ((req->flags & CF_WRITE_TIMEOUT) ? SF_ERR_SRVTO : SF_ERR_SRVCL);
  status = 502;
  goto return_prx_cond;

  return_int_err:
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_INTERNAL;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->internal_errors);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->internal_errors);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->internal_errors);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->internal_errors);
  stream_report_term_evt(s->scf, strm_tevt_type_internal_err);
  status = 500;
  goto return_prx_cond;

  return_bad_req:
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->failed_req);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->failed_req);
  stream_report_term_evt(s->scf, strm_tevt_type_proto_err);
  status = 400;
  /* fall through */

  return_prx_cond:
  http_set_term_flags(s);
  if (txn->status > 0) {
    /* Note: we don't send any error if some data were already sent */
    http_reply_and_close(s, txn->status, NULL);
  } else {
    txn->status = status;
    http_reply_and_close(s, txn->status, http_error_message(s));
  }
  DBG_TRACE_DEVEL("leaving on error ",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
  return 0;
}

/* Reset the stream and the backend stream connector to a situation suitable for attemption connection */
/* Returns 0 if we can attempt to retry, -1 otherwise */
static __inline int do_l7_retry(struct stream *s, struct stconn *sc)
{
  struct channel *req, *res;
  int co_data;

  if (s->conn_retries >= s->max_retries)
    return -1;
  s->conn_retries++;
  if (objt_server(s->target)) {
    if (s->flags & SF_CURR_SESS) {
      s->flags &= ~SF_CURR_SESS;
      _HA_ATOMIC_DEC(&__objt_server(s->target)->cur_sess);
    }
    if (s->sv_tgcounters)
      _HA_ATOMIC_INC(&s->sv_tgcounters->retries);
  }
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->retries);

  req = &s->req;
  res = &s->res;

  /* Remove any write error from the request, and read error from the response */
  s->scf->flags &= ~(SC_FL_EOS|SC_FL_ABRT_DONE|SC_FL_ABRT_WANTED);
  req->flags &= ~(CF_WRITE_TIMEOUT|CF_WROTE_DATA);
  res->flags &= ~(CF_READ_TIMEOUT | CF_READ_EVENT);
  res->analysers &= AN_RES_FLT_END;
  s->conn_err_type = STRM_ET_NONE;
  s->flags &= ~(SF_CONN_EXP | SF_ERR_MASK | SF_FINST_MASK);
  s->conn_exp = TICK_ETERNITY;
  stream_choose_redispatch(s);
  res->to_forward = 0;
  res->analyse_exp = TICK_ETERNITY;

  s->scb->flags &= ~(SC_FL_ERROR|SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED);
  if (sc_reset_endp(s->scb) < 0) {
    s->flags |= SF_ERR_INTERNAL;
    return -1;
  }

  b_free(&req->buf);

  /* Swap the L7 buffer with the channel buffer */
  /* We know we stored the co_data as b_data, so get it there */
  co_data = b_data(&s->txn.http->l7_buffer);
  b_set_data(&s->txn.http->l7_buffer, b_size(&s->txn.http->l7_buffer));

  req->buf = s->txn.http->l7_buffer;
  s->txn.http->l7_buffer = BUF_NULL;
  co_set_data(req, co_data);

  DBG_TRACE_DEVEL("perform a L7 retry", STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s,
      s->txn.http);

  b_reset(&res->buf);
  co_set_data(res, 0);
  return 0;
}

/* This stream analyser waits for a complete HTTP response. It returns 1 if the
 * processing can continue on next analysers, or zero if it either needs more
 * data or wants to immediately abort the response (eg: timeout, error, ...). It
 * is tied to AN_RES_WAIT_HTTP and may may remove itself from s->res.analysers
 * when it has nothing left to do, and may remove any analyser when it wants to
 * abort.
 */
int http_wait_for_response(struct stream *s, struct channel *rep, int an_bit)
{
  /*
   * We will analyze a complete HTTP response to check the its syntax.
   *
   * Once the start line and all headers are received, we may perform a
   * capture of the error (if any), and we will set a few fields. We also
   * logging and finally headers capture.
   */
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct http_msg *msg = &txn->rsp;
  struct htx *htx;
  struct connection *srv_conn;
  struct htx_sl *sl;
  int n, l7_retry_failed = 0;

  DBG_TRACE_ENTER(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn, msg);

  htx = htxbuf(&rep->buf);

  /* Parsing errors are caught here */
  if (htx->flags & HTX_FL_PARSING_ERROR) {
    if (objt_server(s->target))
      health_adjust(__objt_server(s->target), HANA_STATUS_HTTP_HDRRSP);
    goto return_bad_res;
  }
  if (htx->flags & HTX_FL_PROCESSING_ERROR)
    goto return_int_err;

  /*
   * Now we quickly check if we have found a full valid response.
   * If not so, we check the FD and buffer states before leaving.
   * A full response is indicated by the fact that we have seen
   * the double LF/CRLF, so the state is >= HTTP_MSG_BODY. Invalid
   * responses are checked first.
   *
   * Depending on whether the client is still there or not, we
   * may send an error response back or not. Note that normally
   * we should only check for HTTP status there, and check I/O
   * errors somewhere else.
   */
  next_one:
  if (unlikely(htx_is_empty(htx) || htx->first == -1)) {
    /* 1: have we encountered a read error ? */
    if (s->scb->flags & SC_FL_ERROR) {
      struct connection *conn = sc_conn(s->scb);

      if (!(s->flags & SF_SRV_REUSED) && objt_server(s->target))
        health_adjust(__objt_server(s->target), HANA_STATUS_HTTP_READ_ERROR);

      if ((txn->flags & TX_L7_RETRY) &&
          (s->be->retry_type & PR_RE_DISCONNECTED) &&
          (!conn || conn->err_code != CO_ER_SSL_EARLY_FAILED)) {
        if (co_data(rep) || do_l7_retry(s, s->scb) == 0)
          return 0;
        l7_retry_failed = 1;
      }

      /* Perform a L7 retry on empty response or because server refuses the early data. */
      if ((txn->flags & TX_L7_RETRY) &&
          (s->be->retry_type & PR_RE_EARLY_ERROR) &&
          conn && conn->err_code == CO_ER_SSL_EARLY_FAILED) {
        if (do_l7_retry(s, s->scb) == 0) {
          DBG_TRACE_DEVEL("leaving on L7 retry",
              STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
          return 0;
        }
        l7_retry_failed = 1;
      }

      if (!l7_retry_failed && (s->flags & SF_SRV_REUSED))
        goto abort_keep_alive;

      if (s->be_tgcounters)
        _HA_ATOMIC_INC(&s->be_tgcounters->failed_resp);
      if (s->sv_tgcounters)
        _HA_ATOMIC_INC(&s->sv_tgcounters->failed_resp);

      /* if the server refused the early data, just send a 425 */
      if (conn && conn->err_code == CO_ER_SSL_EARLY_FAILED)
        txn->status = 425;
      else {
        txn->status = 502;
        stream_inc_http_fail_ctr(s);
      }

      s->scb->flags |= SC_FL_NOLINGER;

      if (!(s->flags & SF_ERR_MASK))
        s->flags |= SF_ERR_SRVCL;
      http_set_term_flags(s);

      http_reply_and_close(s, txn->status, http_error_message(s));
      DBG_TRACE_DEVEL("leaving on error",
          STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
      return 0;
    }

    /* 2: read timeout : return a 504 to the client. */
    else if (rep->flags & CF_READ_TIMEOUT) {
      if (objt_server(s->target))
        health_adjust(__objt_server(s->target), HANA_STATUS_HTTP_READ_TIMEOUT);

      if ((txn->flags & TX_L7_RETRY) &&
          (s->be->retry_type & PR_RE_TIMEOUT)) {
        if (co_data(rep) || do_l7_retry(s, s->scb) == 0) {
          DBG_TRACE_DEVEL("leaving on L7 retry",
              STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
          return 0;
        }
      }
      if (s->be_tgcounters)
        _HA_ATOMIC_INC(&s->be_tgcounters->failed_resp);
      if (s->sv_tgcounters)
        _HA_ATOMIC_INC(&s->sv_tgcounters->failed_resp);

      txn->status = 504;
      stream_inc_http_fail_ctr(s);
      s->scb->flags |= SC_FL_NOLINGER;

      if (!(s->flags & SF_ERR_MASK))
        s->flags |= SF_ERR_SRVTO;
      http_set_term_flags(s);

      http_reply_and_close(s, txn->status, http_error_message(s));
      DBG_TRACE_DEVEL("leaving on error",
          STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
      return 0;
    }

    /* 3: client abort with an abortonclose */
    else if ((s->scb->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) && (s->scb->flags & SC_FL_SHUT_DONE) &&
       (s->scf->flags & (SC_FL_EOS|SC_FL_ABRT_DONE))) {
      if (sess->fe_tgcounters)
        _HA_ATOMIC_INC(&sess->fe_tgcounters->cli_aborts);
      if (s->be_tgcounters)
        _HA_ATOMIC_INC(&s->be_tgcounters->cli_aborts);
      if (sess->li_tgcounters)
        _HA_ATOMIC_INC(&sess->li_tgcounters->cli_aborts);
      if (s->sv_tgcounters)
        _HA_ATOMIC_INC(&s->sv_tgcounters->cli_aborts);

      txn->status = 400;

      if (!(s->flags & SF_ERR_MASK))
        s->flags |= SF_ERR_CLICL;
      http_set_term_flags(s);

      http_reply_and_close(s, txn->status, http_error_message(s));

      /* process_stream() will take care of the error */
      DBG_TRACE_DEVEL("leaving on error",
          STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
      return 0;
    }

    /* 4: close from server, capture the response if the server has started to respond */
    else if (s->scb->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) {
      if (!(s->flags & SF_SRV_REUSED) && objt_server(s->target))
        health_adjust(__objt_server(s->target), HANA_STATUS_HTTP_BROKEN_PIPE);

      if ((txn->flags & TX_L7_RETRY) &&
          (s->be->retry_type & PR_RE_DISCONNECTED)) {
        if (co_data(rep) || do_l7_retry(s, s->scb) == 0) {
          DBG_TRACE_DEVEL("leaving on L7 retry",
              STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
          return 0;
        }
        l7_retry_failed = 1;
      }

      if (!l7_retry_failed && (s->flags & SF_SRV_REUSED))
        goto abort_keep_alive;

      if (s->be_tgcounters)
        _HA_ATOMIC_INC(&s->be_tgcounters->failed_resp);
      if (s->sv_tgcounters)
        _HA_ATOMIC_INC(&s->sv_tgcounters->failed_resp);

      txn->status = 502;
      stream_inc_http_fail_ctr(s);
      s->scb->flags |= SC_FL_NOLINGER;

      if (!(s->flags & SF_ERR_MASK))
        s->flags |= SF_ERR_SRVCL;
      http_set_term_flags(s);

      http_reply_and_close(s, txn->status, http_error_message(s));
      DBG_TRACE_DEVEL("leaving on error",
          STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
      return 0;
    }

    /* 5: write error to client (we don't send any message then) */
    else if (sc_ep_test(s->scf, SE_FL_ERR_PENDING)) {
      if (s->flags & SF_SRV_REUSED)
        goto abort_keep_alive;

      if (s->be_tgcounters)
        _HA_ATOMIC_INC(&s->be_tgcounters->failed_resp);
      if (s->sv_tgcounters)
        _HA_ATOMIC_INC(&s->sv_tgcounters->failed_resp);
      rep->analysers &= AN_RES_FLT_END;

      if (!(s->flags & SF_ERR_MASK))
        s->flags |= SF_ERR_CLICL;
      http_set_term_flags(s);

      /* process_stream() will take care of the error */
      http_reply_and_close(s, txn->status, NULL);
      DBG_TRACE_DEVEL("leaving on error",
          STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
      return 0;
    }

    channel_dont_close(rep);
    s->scb->flags |= SC_FL_RCV_ONCE; /* try to get back here ASAP */
    DBG_TRACE_DEVEL("waiting for more data",
        STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
    return 0;
  }

  /* More interesting part now : we know that we have a complete
   * response which at least looks like HTTP. We have an indicator
   * of each header's length, so we can parse them quickly.
   */
  BUG_ON(htx_get_first_type(htx) != HTX_BLK_RES_SL);
  sl = http_get_stline(htx);

  if ((sl->flags & HTX_SL_F_NOT_HTTP) || HTX_SL_RES_VLEN(sl) != 8)  {
    /* Not an HTTP response */
    msg->vsn = 0;
  }
  else if (objt_server(s->target)) {
    /* HTTP response from a server, use it to set the response version */
    char *ptr;

    ptr = HTX_SL_RES_VPTR(sl);
    msg->vsn = ((ptr[5] - '0') << 4) + (ptr[7] - '0');

    /* If front endpoint is an applet, use the server version for the request */
    if (sc_ep_test(s->scf, SE_FL_T_APPLET))
      txn->req.vsn = msg->vsn;
  }
  else {
    /* HTTP response from an applet, use the request version for the response */
    msg->vsn = txn->req.vsn;
  }

  /* Adjust server's health based on status code. Note: status codes 501
   * and 505 are triggered on demand by client request, so we must not
   * count them as server failures.
   */
  if (objt_server(s->target)) {
    if (sl->info.res.status >= 100 && (sl->info.res.status < 500 || sl->info.res.status == 501 || sl->info.res.status == 505))
      health_adjust(__objt_server(s->target), HANA_STATUS_HTTP_OK);
    else
      health_adjust(__objt_server(s->target), HANA_STATUS_HTTP_STS);
  }

  /* Perform a L7 retry because of the status code */
  if ((txn->flags & TX_L7_RETRY) &&
      l7_status_match(s->be, sl->info.res.status) &&
      do_l7_retry(s, s->scb) == 0) {
    DBG_TRACE_DEVEL("leaving on L7 retry", STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
    return 0;
  }

  msg->msg_state = HTTP_MSG_BODY;


  /* 0: we might have to print this header in debug mode */
  if (unlikely((global.mode & MODE_DEBUG) &&
         (!(global.mode & MODE_QUIET) || (global.mode & MODE_VERBOSE)))) {
    int32_t pos;

    http_debug_stline("srvrep", s, sl);

    for (pos = htx_get_first(htx); pos != -1; pos = htx_get_next(htx, pos)) {
      struct htx_blk *blk = htx_get_blk(htx, pos);
      enum htx_blk_type type = htx_get_blk_type(blk);

      if (type == HTX_BLK_EOH)
        break;
      if (type != HTX_BLK_HDR)
        continue;

      http_debug_hdr("srvhdr", s,
               htx_get_blk_name(htx, blk),
               htx_get_blk_value(htx, blk));
    }
  }

  /* 1: get the status code and the version. Also set HTTP flags */
  txn->server_status = txn->status = sl->info.res.status;
  if (sl->flags & HTX_SL_F_VER_11)
                msg->flags |= HTTP_MSGF_VER_11;
  if (sl->flags & HTX_SL_F_XFER_LEN) {
    msg->flags |= HTTP_MSGF_XFER_LEN;
    if (sl->flags & HTX_SL_F_CLEN)
      msg->flags |= HTTP_MSGF_CNT_LEN;
    else if (sl->flags & HTX_SL_F_CHNK)
      msg->flags |= HTTP_MSGF_TE_CHNK;
  }
  if (sl->flags & HTX_SL_F_BODYLESS)
    msg->flags |= HTTP_MSGF_BODYLESS;
  if (sl->flags & HTX_SL_F_CONN_UPG)
    msg->flags |= HTTP_MSGF_CONN_UPG;

  /* when the client triggers a 4xx from the server, it's most often due
   * to a missing object or permission. These events should be tracked
   * because if they happen often, it may indicate a brute force or a
   * vulnerability scan.
   */
  if (http_status_matches(http_err_status_codes, txn->status))
    stream_inc_http_err_ctr(s);

  if (http_status_matches(http_fail_status_codes, txn->status))
    stream_inc_http_fail_ctr(s);

  if (s->sv_tgcounters) {
    n = txn->status / 100;
    if (n < 1 || n > 5)
      n = 0;

    _HA_ATOMIC_INC(&s->sv_tgcounters->p.http.rsp[n]);
    _HA_ATOMIC_INC(&s->sv_tgcounters->p.http.cum_req);
  }

  /*
   * We may be facing a 100-continue response, or any other informational
   * 1xx response which is non-final, in which case this is not the right
   * response, and we're waiting for the next one. Let's allow this response
   * to go to the client and wait for the next one. There's an exception for
   * 101 which is used later in the code to switch protocols.
   */
  if (txn->status < 200 &&
      (txn->status == 100 || txn->status >= 102)) {
    FLT_STRM_CB(s, flt_http_reset(s, msg));
    htx->first = channel_htx_fwd_headers(rep, htx);
    msg->msg_state = HTTP_MSG_RPBEFORE;
    msg->flags = 0;
    txn->server_status = txn->status = 0;
    s->logs.t_data = -1; /* was not a response yet */
    s->scf->flags |= SC_FL_SND_ASAP; /* Send ASAP informational messages */
    goto next_one;
  }

  /* A 101-switching-protocols must contains a Connection header with the
   * "upgrade" option and the request too. It means both are agree to
   * upgrade. It is not so strict because there is no test on the Upgrade
   * header content. But it is probably stronger enough for now.
   */
  if (txn->status == 101 &&
      (!(txn->req.flags & HTTP_MSGF_CONN_UPG) || !(txn->rsp.flags & HTTP_MSGF_CONN_UPG))) {
    if (objt_server(s->target))
      health_adjust(__objt_server(s->target), HANA_STATUS_HTTP_HDRRSP);
    goto return_bad_res;
  }

  /*
   * 2: check for cacheability.
   */

  switch (txn->status) {
  case 200:
  case 203:
  case 204:
  case 206:
  case 300:
  case 301:
  case 404:
  case 405:
  case 410:
  case 414:
  case 501:
    break;
  default:
    /* RFC7231#6.1:
     *   Responses with status codes that are defined as
     *   cacheable by default (e.g., 200, 203, 204, 206,
     *   300, 301, 404, 405, 410, 414, and 501 in this
     *   specification) can be reused by a cache with
     *   heuristic expiration unless otherwise indicated
     *   by the method definition or explicit cache
     *   controls [RFC7234]; all other status codes are
     *   not cacheable by default.
     */
    txn->flags &= ~(TX_CACHEABLE | TX_CACHE_COOK);
    break;
  }

  /*
   * 3: we may need to capture headers
   */
  s->logs.logwait &= ~LW_RESP;
  if (unlikely((s->logs.logwait & LW_RSPHDR) && s->res_cap))
    http_capture_headers(htx, s->res_cap, sess->fe->rsp_cap);

  /* Skip parsing if no content length is possible. */
  if (unlikely((txn->meth == HTTP_METH_CONNECT && txn->status >= 200 && txn->status < 300) ||
         txn->status == 101)) {
    /* Either we've established an explicit tunnel, or we're
     * switching the protocol. In both cases, we're very unlikely
     * to understand the next protocols. We have to switch to tunnel
     * mode, so that we transfer the request and responses then let
     * this protocol pass unmodified. When we later implement specific
     * parsers for such protocols, we'll want to check the Upgrade
     * header which contains information about that protocol for
     * responses with status 101 (eg: see RFC2817 about TLS).
     */
    txn->flags |= TX_CON_WANT_TUN;
  }

  /* Check for NTML authentication headers in 401 (WWW-Authenticate) and
   * 407 (Proxy-Authenticate) responses and set the connection to
   * private.
   *
   * Note that this is not performed when using a true multiplexer unless
   * connection is already attached to the session as nothing prevents it
   * from being shared already by several sessions here.
   */
  srv_conn = sc_conn(s->scb);
  if (srv_conn &&
      (LIST_INLIST(&srv_conn->sess_el) || strcmp(srv_conn->mux->name, "H1") == 0)) {
    struct ist hdr;
    struct http_hdr_ctx ctx;

    if (txn->status == 401)
      hdr = ist("WWW-Authenticate");
    else if (txn->status == 407)
      hdr = ist("Proxy-Authenticate");
    else
      goto end;

    ctx.blk = NULL;
    while (http_find_header(htx, hdr, &ctx, 0)) {
      /* If www-authenticate contains "Negotiate", "Nego2", or "NTLM",
       * possibly followed by blanks and a base64 string, the connection
       * is private. Since it's a mess to deal with, we only check for
       * values starting with "NTLM" or "Nego". Note that often multiple
       * headers are sent by the server there.
       */
      if ((ctx.value.len >= 4 && strncasecmp(ctx.value.ptr, "Nego", 4) == 0) ||
          (ctx.value.len >= 4 && strncasecmp(ctx.value.ptr, "NTLM", 4) == 0)) {
        sess->flags |= SESS_FL_PREFER_LAST;
        conn_set_private(srv_conn);
        /* If it fail now, the same will be done in mux->detach() callback */
        session_add_conn(sess, srv_conn);
        break;
      }
    }
  }

  end:
  /* Now, L7 buffer is useless, it can be released */
  b_free(&txn->l7_buffer);

  /* we want to have the response time before we start processing it */
  s->logs.t_data = ns_to_ms(now_ns - s->logs.accept_ts);

  /* end of job, return OK */
  rep->analysers &= ~an_bit;
  rep->analyse_exp = TICK_ETERNITY;
  channel_auto_close(rep);
  DBG_TRACE_LEAVE(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 1;

 return_int_err:
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->internal_errors);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->internal_errors);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->internal_errors);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->internal_errors);
  txn->status = 500;
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_INTERNAL;
  stream_report_term_evt(s->scb, strm_tevt_type_internal_err);
  goto return_prx_cond;

  return_bad_res:
  if ((s->be->retry_type & PR_RE_JUNK_REQUEST) &&
      (txn->flags & TX_L7_RETRY) &&
      do_l7_retry(s, s->scb) == 0) {
    DBG_TRACE_DEVEL("leaving on L7 retry",
        STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
    return 0;
  }

  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->failed_resp);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->failed_resp);

  txn->status = 502;
  stream_inc_http_fail_ctr(s);
  stream_report_term_evt(s->scb, strm_tevt_type_proto_err);
  /* fall through */

 return_prx_cond:
  http_set_term_flags(s);
  http_reply_and_close(s, txn->status, http_error_message(s));

  s->scb->flags |= SC_FL_NOLINGER;
  DBG_TRACE_DEVEL("leaving on error",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
  return 0;

 abort_keep_alive:
  /* A keep-alive request to the server failed on a network error.
   * The client is required to retry. We need to close without returning
   * any other information so that the client retries.
   */
  txn->status = 0;
  s->logs.logwait = 0;
  s->logs.level = 0;
  s->scf->flags &= ~SC_FL_SND_EXP_MORE; /* speed up sending a previous response */
  http_reply_and_close(s, txn->status, NULL);
  DBG_TRACE_DEVEL("leaving by closing K/A connection",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;
}

/* This function performs all the processing enabled for the current response.
 * It normally returns 1 unless it wants to break. It relies on buffers flags,
 * and updates s->res.analysers. It might make sense to explode it into several
 * other functions. It works like process_request (see indications above).
 */
int http_process_res_common(struct stream *s, struct channel *rep, int an_bit, struct proxy *px)
{
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct http_msg *msg = &txn->rsp;
  struct htx *htx;
  struct proxy *cur_proxy;
  enum rule_result ret = HTTP_RULE_RES_CONT;
  uint8_t do_log = 0;

  if (unlikely(msg->msg_state < HTTP_MSG_BODY)) /* we need more data */
    return 0;

  DBG_TRACE_ENTER(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn, msg);

  htx = htxbuf(&rep->buf);

  /* The stats applet needs to adjust the Connection header but we don't
   * apply any filter there.
   */
  if (unlikely(objt_applet(s->target) == &http_stats_applet)) {
    rep->analysers &= ~an_bit;
    rep->analyse_exp = TICK_ETERNITY;
    goto end;
  }

  /*
   * We will have to evaluate the filters.
   * As opposed to version 1.2, now they will be evaluated in the
   * filters order and not in the header order. This means that
   * each filter has to be validated among all headers.
   *
   * Filters are tried with ->be first, then with ->fe if it is
   * different from ->be.
   *
   * Maybe we are in resume condiion. In this case I choose the
   * "struct proxy" which contains the rule list matching the resume
   * pointer. If none of these "struct proxy" match, I initialise
   * the process with the first one.
   *
   * In fact, I check only correspondence between the current list
   * pointer and the ->fe rule list. If it doesn't match, I initialize
   * the loop with the ->be.
   */
  if (s->current_rule_list == &sess->fe->http_res_rules ||
      (sess->fe->defpx && s->current_rule_list == &sess->fe->defpx->http_res_rules))
    cur_proxy = sess->fe;
  else
    cur_proxy = s->be;

  while (1) {
    /* evaluate http-response rules */
    if (ret == HTTP_RULE_RES_CONT || ret == HTTP_RULE_RES_STOP) {
      struct list *def_rules, *rules;

      def_rules = ((cur_proxy->defpx && (cur_proxy == s->be || cur_proxy->defpx != s->be->defpx)) ? &cur_proxy->defpx->http_res_rules : NULL);
      rules = &cur_proxy->http_res_rules;

      ret = http_res_get_intercept_rule(cur_proxy, def_rules, rules, s, 0);

      switch (ret) {
      case HTTP_RULE_RES_YIELD: /* some data miss, call the function later. */
        goto return_prx_yield;

      case HTTP_RULE_RES_FYIELD: /* we must try again after context-switch */
        goto return_prx_fyield;

      case HTTP_RULE_RES_CONT:
      case HTTP_RULE_RES_STOP: /* nothing to do */
        break;

      case HTTP_RULE_RES_DENY: /* deny or tarpit */
        goto deny;

      case HTTP_RULE_RES_ABRT: /* abort request, response already sent */
        stream_report_term_evt(s->scb, strm_tevt_type_intercepted);
        goto return_prx_cond;

      case HTTP_RULE_RES_DONE: /* OK, but terminate request processing (eg: redirect) */
        goto done;

      case HTTP_RULE_RES_BADREQ: /* failed with a bad request */
        goto return_bad_res;

      case HTTP_RULE_RES_ERROR: /* failed with a bad request */
        goto return_int_err;
      }

    }

    /* check whether we're already working on the frontend */
    if (cur_proxy == sess->fe)
      break;
    cur_proxy = sess->fe;
  }

  /* OK that's all we can do for 1xx responses */
  if (unlikely(txn->status < 200 && txn->status != 101))
    goto end;

  /*
   * Now check for a server cookie.
   */
  if (s->be->cookie_name || sess->fe->capture_name || (s->be->options & PR_O_CHK_CACHE))
    http_manage_server_side_cookies(s, rep);

  /*
   * Check for cache-control or pragma headers if required.
   */
  if ((s->be->options & PR_O_CHK_CACHE) || (s->be->ck_opts & PR_CK_NOC))
    http_check_response_for_cacheability(s, rep);

  /*
   * Add server cookie in the response if needed
   */
  if (objt_server(s->target) && (s->be->ck_opts & PR_CK_INS) &&
      !((txn->flags & TX_SCK_FOUND) && (s->be->ck_opts & PR_CK_PSV)) &&
      (!(s->flags & SF_DIRECT) ||
       ((s->be->cookie_maxidle || txn->cookie_last_date) &&
        (!txn->cookie_last_date || (txn->cookie_last_date - date.tv_sec) < 0)) ||
       (s->be->cookie_maxlife && !txn->cookie_first_date) ||  // set the first_date
       (!s->be->cookie_maxlife && txn->cookie_first_date)) && // remove the first_date
      (!(s->be->ck_opts & PR_CK_POST) || (txn->meth == HTTP_METH_POST)) &&
      !(s->flags & SF_IGNORE_PRST)) {
    /* the server is known, it's not the one the client requested, or the
     * cookie's last seen date needs to be refreshed. We have to
     * insert a set-cookie here, except if we want to insert only on POST
     * requests and this one isn't. Note that servers which don't have cookies
     * (eg: some backup servers) will return a full cookie removal request.
     */
    if (!__objt_server(s->target)->cookie) {
      chunk_printf(&trash,
             "%s=; Expires=Thu, 01-Jan-1970 00:00:01 GMT; path=/",
             s->be->cookie_name);
    }
    else {
      chunk_printf(&trash, "%s=%s", s->be->cookie_name, __objt_server(s->target)->cookie);

      if (s->be->cookie_maxidle || s->be->cookie_maxlife) {
        /* emit last_date, which is mandatory */
        trash.area[trash.data++] = COOKIE_DELIM_DATE;
        s30tob64((date.tv_sec+3) >> 2,
           trash.area + trash.data);
        trash.data += 5;

        if (s->be->cookie_maxlife) {
          /* emit first_date, which is either the original one or
           * the current date.
           */
          trash.area[trash.data++] = COOKIE_DELIM_DATE;
          s30tob64(txn->cookie_first_date ?
             txn->cookie_first_date >> 2 :
             (date.tv_sec+3) >> 2,
             trash.area + trash.data);
          trash.data += 5;
        }
      }
      chunk_appendf(&trash, "; path=/");
    }

    if (s->be->cookie_domain)
      chunk_appendf(&trash, "; domain=%s", s->be->cookie_domain);

    if (s->be->ck_opts & PR_CK_HTTPONLY)
      chunk_appendf(&trash, "; HttpOnly");

    if (s->be->ck_opts & PR_CK_SECURE)
      chunk_appendf(&trash, "; Secure");

    if (s->be->cookie_attrs)
      chunk_appendf(&trash, "; %s", s->be->cookie_attrs);

    if (unlikely(!http_add_header(htx, ist("Set-Cookie"), ist2(trash.area, trash.data), 0)))
      goto return_fail_rewrite;

    txn->flags &= ~TX_SCK_MASK;
    if (__objt_server(s->target)->cookie && (s->flags & SF_DIRECT))
      /* the server did not change, only the date was updated */
      txn->flags |= TX_SCK_UPDATED;
    else
      txn->flags |= TX_SCK_INSERTED;

    /* Here, we will tell an eventual cache on the client side that we don't
     * want it to cache this reply because HTTP/1.0 caches also cache cookies !
     * Some caches understand the correct form: 'no-cache="set-cookie"', but
     * others don't (eg: apache <= 1.3.26). So we use 'private' instead.
     */
    if ((s->be->ck_opts & PR_CK_NOC) && (txn->flags & TX_CACHEABLE)) {

      txn->flags &= ~TX_CACHEABLE & ~TX_CACHE_COOK;

      if (unlikely(!http_add_header(htx, ist("Cache-control"), ist("private"), 0)))
        goto return_fail_rewrite;
    }
  }

  /*
   * Check if result will be cacheable with a cookie.
   * We'll block the response if security checks have caught
   * nasty things such as a cacheable cookie.
   */
  if (((txn->flags & (TX_CACHEABLE | TX_CACHE_COOK | TX_SCK_PRESENT)) ==
       (TX_CACHEABLE | TX_CACHE_COOK | TX_SCK_PRESENT)) &&
      (s->be->options & PR_O_CHK_CACHE)) {
    /* we're in presence of a cacheable response containing
     * a set-cookie header. We'll block it as requested by
     * the 'checkcache' option, and send an alert.
     */
    ha_alert("Blocking cacheable cookie in response from instance %s, server %s.\n",
       s->be->id, objt_server(s->target) ? __objt_server(s->target)->id : "<dispatch>");
    send_log(s->be, LOG_ALERT,
       "Blocking cacheable cookie in response from instance %s, server %s.\n",
       s->be->id, objt_server(s->target) ? __objt_server(s->target)->id : "<dispatch>");
    goto deny;
  }

  end:
  /*
   * Evaluate after-response rules before forwarding the response. rules
   * from the backend are evaluated first, then one from the frontend if
   * it differs.
   */
  if (!http_eval_after_res_rules(s))
    goto return_int_err;

  /* Filter the response headers if there are filters attached to the
   * stream.
   */
  if (HAS_FILTERS(s))
    rep->analysers |= AN_RES_FLT_HTTP_HDRS;

  /* Always enter in the body analyzer */
  rep->analysers &= ~AN_RES_FLT_XFER_DATA;
  rep->analysers |= AN_RES_HTTP_XFER_BODY;

  if (sess->fe->to_log == LW_LOGSTEPS) {
    if (log_orig_proxy(LOG_ORIG_TXN_RESPONSE, sess->fe))
      do_log = 1;
  }
  else if ((!lf_expr_isempty(&sess->fe->logformat) && !(s->logs.logwait & LW_BYTES)))
    do_log = 1;

  /* if the user wants to log as soon as possible, without counting
   * bytes from the server, then this is the right moment. We have
   * to temporarily assign req_in to log what we currently have.
   */
  if (do_log) {
    s->logs.t_close = s->logs.t_data; /* to get a valid end date */
    s->logs.res_in = htx->data;
    s->do_log(s, log_orig(LOG_ORIG_TXN_RESPONSE, LOG_ORIG_FL_NONE));
    s->logs.res_in = 0;
  }

 done:
  DBG_TRACE_LEAVE(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  rep->analysers &= ~an_bit;
  rep->analyse_exp = TICK_ETERNITY;
  s->current_rule = s->current_rule_list = NULL;
  return 1;

 deny:
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->denied_resp);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->denied_resp);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->denied_resp);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->denied_resp);
  stream_report_term_evt(s->scb, strm_tevt_type_intercepted);
  goto return_prx_err;

 return_fail_rewrite:
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_PRXCOND;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->failed_rewrites);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->failed_rewrites);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->failed_rewrites);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->failed_rewrites);
  /* fall through */

 return_int_err:
  txn->status = 500;
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_INTERNAL;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->internal_errors);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->internal_errors);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->internal_errors);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->internal_errors);
  stream_report_term_evt(s->scb, strm_tevt_type_internal_err);
  goto return_prx_err;

 return_bad_res:
  s->logs.t_data = -1; /* was not a valid response */
  txn->status = 502;
  stream_inc_http_fail_ctr(s);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->failed_resp);
  if (objt_server(s->target)) {
    if (s->sv_tgcounters)
      _HA_ATOMIC_INC(&s->sv_tgcounters->failed_resp);
    health_adjust(__objt_server(s->target), HANA_STATUS_HTTP_RSP);
  }
  stream_report_term_evt(s->scb, strm_tevt_type_proto_err);
  /* fall through */

 return_prx_err:
  http_set_term_flags(s);
  http_reply_and_close(s, txn->status, http_error_message(s));
  /* fall through */

 return_prx_cond:
  s->scb->flags |= SC_FL_NOLINGER;
  http_set_term_flags(s);

  rep->analysers &= AN_RES_FLT_END;
  s->req.analysers &= AN_REQ_FLT_END;
  rep->analyse_exp = TICK_ETERNITY;
  s->current_rule = s->current_rule_list = NULL;
  DBG_TRACE_DEVEL("leaving on error",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
  return 0;

 return_prx_yield:
  channel_dont_close(rep);
  DBG_TRACE_DEVEL("waiting for more data",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;

 return_prx_fyield:
  channel_dont_close(rep);
  DBG_TRACE_DEVEL("forced yield",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;

}

/* This function is an analyser which forwards response body (including chunk
 * sizes if any). It is called as soon as we must forward, even if we forward
 * zero byte. The only situation where it must not be called is when we're in
 * tunnel mode and we want to forward till the close. It's used both to forward
 * remaining data and to resync after end of body. It expects the msg_state to
 * be between MSG_BODY and MSG_DONE (inclusive). It returns zero if it needs to
 * read more data, or 1 once we can go on with next request or end the stream.
 *
 * It is capable of compressing response data both in content-length mode and
 * in chunked mode. The state machines follows different flows depending on
 * whether content-length and chunked modes are used, since there are no
 * trailers in content-length :
 *
 *       chk-mode        cl-mode
 *          ,----- BODY -----.
 *         /                  \
 *        V     size > 0       V    chk-mode
 *  .--> SIZE -------------> DATA -------------> CRLF
 *  |     | size == 0          | last byte         |
 *  |     v      final crlf    v inspected         |
 *  |  TRAILERS -----------> DONE                  |
 *  |                                              |
 *  `----------------------------------------------'
 *
 * Compression only happens in the DATA state, and must be flushed in final
 * states (TRAILERS/DONE) or when leaving on missing data. Normal forwarding
 * is performed at once on final states for all bytes parsed, or when leaving
 * on missing data.
 */
int http_response_forward_body(struct stream *s, struct channel *res, int an_bit)
{
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct http_msg *msg = &s->txn.http->rsp;
  struct htx *htx;
  int ret;

  DBG_TRACE_ENTER(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn, msg);

  htx = htxbuf(&res->buf);

  if (htx->flags & HTX_FL_PARSING_ERROR)
    goto return_bad_res;
  if (htx->flags & HTX_FL_PROCESSING_ERROR)
    goto return_int_err;

  if (msg->msg_state == HTTP_MSG_BODY)
    msg->msg_state = HTTP_MSG_DATA;

  /* in most states, we should abort in case of early close */
  channel_auto_close(res);

  if (res->to_forward) {
    if (res->to_forward == CHN_INFINITE_FORWARD) {
      if (s->scb->flags & SC_FL_EOI)
        msg->msg_state = HTTP_MSG_ENDING;
    }
    else {
      /* We can't process the buffer's contents yet */
      res->flags |= CF_WAKE_WRITE;
      goto missing_data_or_waiting;
    }
  }

  if (msg->msg_state >= HTTP_MSG_ENDING)
    goto ending;

  if ((txn->meth == HTTP_METH_CONNECT && txn->status >= 200 && txn->status < 300) || txn->status == 101 ||
      (!(msg->flags & HTTP_MSGF_XFER_LEN) && !HAS_RSP_DATA_FILTERS(s))) {
    msg->msg_state = HTTP_MSG_ENDING;
    goto ending;
  }

  /* Forward input data. We get it by removing all outgoing data not
   * forwarded yet from HTX data size. If there are some data filters, we
   * let them decide the amount of data to forward.
   */
  if (HAS_RSP_DATA_FILTERS(s)) {
    ret  = flt_http_payload(s, msg, htx->data);
    if (ret < 0)
      goto return_bad_res;
    c_adv(res, ret);
  }
  else {
    c_adv(res, htx->data - co_data(res));
    if ((global.tune.options & GTUNE_USE_FAST_FWD) && (msg->flags & HTTP_MSGF_XFER_LEN))
      channel_htx_forward_forever(res, htx);
  }

  if (htx->data != co_data(res))
    goto missing_data_or_waiting;

  if (!(msg->flags & HTTP_MSGF_XFER_LEN) && (s->scb->flags & (SC_FL_EOS|SC_FL_ABRT_DONE))) {
    msg->msg_state = HTTP_MSG_ENDING;
    goto ending;
  }

  /* Check if the end-of-message is reached and if so, switch the message
   * in HTTP_MSG_ENDING state. Then if all data was marked to be
   * forwarded, set the state to HTTP_MSG_DONE.
   */
  if (!(htx->flags & HTX_FL_EOM))
    goto missing_data_or_waiting;

  msg->msg_state = HTTP_MSG_ENDING;

  ending:
  s->scf->flags &= ~SC_FL_SND_EXP_MORE; /* no more data are expected to be sent */

  /* other states, ENDING...TUNNEL */
  if (msg->msg_state >= HTTP_MSG_DONE)
    goto done;

  if (HAS_RSP_DATA_FILTERS(s)) {
    ret = flt_http_end(s, msg);
    if (ret <= 0) {
      if (!ret)
        goto missing_data_or_waiting;
      goto return_bad_res;
    }
  }

  if (!(txn->flags & TX_CON_WANT_TUN) && !(msg->flags & HTTP_MSGF_XFER_LEN)) {
    /* One-side tunnel */
    msg->msg_state = HTTP_MSG_TUNNEL;
  }
  else {
    msg->msg_state = HTTP_MSG_DONE;
    res->to_forward = 0;
  }

  done:

  channel_dont_close(res);

  if ((s->scf->flags & SC_FL_SHUT_DONE) && co_data(res)) {
    /* response errors are most likely due to the client aborting
     * the transfer. */
    goto return_cli_abort;
  }

  http_end_response(s);
  if (!(res->analysers & an_bit)) {
    DBG_TRACE_LEAVE(STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
    return 1;
  }
  DBG_TRACE_DEVEL("waiting for the end of the HTTP txn",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;

  missing_data_or_waiting:
  if (s->scf->flags & SC_FL_SHUT_DONE)
    goto return_cli_abort;

  /* stop waiting for data if the input is closed before the end. If the
   * client side was already closed, it means that the client has aborted,
   * so we don't want to count this as a server abort. Otherwise it's a
   * server abort.
   */
  if (msg->msg_state < HTTP_MSG_ENDING && (s->scb->flags & (SC_FL_EOS|SC_FL_ABRT_DONE))) {
    if ((s->scf->flags & SC_FL_EOS) && (s->scb->flags & (SC_FL_ABRT_DONE|SC_FL_SHUT_DONE)) == (SC_FL_ABRT_DONE|SC_FL_SHUT_DONE))
      goto return_cli_abort;
    /* If we have some pending data, we continue the processing */
    if (htx_is_empty(htx))
      goto return_srv_abort;
  }

  /* When TE: chunked is used, we need to get there again to parse
   * remaining chunks even if the server has closed, so we don't want to
   * set CF_DONTCLOSE. Similarly when there is a content-leng or if there
   * are filters registered on the stream, we don't want to forward a
   * close
   */
  if ((msg->flags & HTTP_MSGF_XFER_LEN) || HAS_RSP_DATA_FILTERS(s))
    channel_dont_close(res);

  /* We know that more data are expected, but we couldn't send more that
   * what we did. So we always set the SC_FL_SND_EXP_MORE flag so that the
   * system knows it must not set a PUSH on this first part. Interactive
   * modes are already handled by the stream sock layer. We must not do
   * this in content-length mode because it could present the MSG_MORE
   * flag with the last block of forwarded data, which would cause an
   * additional delay to be observed by the receiver.
   */
  if (HAS_RSP_DATA_FILTERS(s))
    s->scf->flags |= SC_FL_SND_EXP_MORE;

  /* the stream handler will take care of timeouts and errors */
  DBG_TRACE_DEVEL("waiting for more data to forward",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA, s, txn);
  return 0;

  return_srv_abort:
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->srv_aborts);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->srv_aborts);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->srv_aborts);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->srv_aborts);
  stream_inc_http_fail_ctr(s);
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= ((res->flags & CF_READ_TIMEOUT) ? SF_ERR_SRVTO : SF_ERR_SRVCL);
  goto return_error;

  return_cli_abort:
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->cli_aborts);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->cli_aborts);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->cli_aborts);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->cli_aborts);
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= ((res->flags & CF_WRITE_TIMEOUT) ? SF_ERR_CLITO : SF_ERR_CLICL);
  goto return_error;

  return_int_err:
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->internal_errors);
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->internal_errors);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->internal_errors);
  if (s->sv_tgcounters)
    _HA_ATOMIC_INC(&s->sv_tgcounters->internal_errors);
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_INTERNAL;
  stream_report_term_evt(s->scb, strm_tevt_type_internal_err);
  goto return_error;

  return_bad_res:
  if (s->be_tgcounters)
    _HA_ATOMIC_INC(&s->be_tgcounters->failed_resp);
  if (objt_server(s->target)) {
    if (s->sv_tgcounters)
      _HA_ATOMIC_INC(&s->sv_tgcounters->failed_resp);
    health_adjust(__objt_server(s->target), HANA_STATUS_HTTP_RSP);
  }
  stream_inc_http_fail_ctr(s);
  stream_report_term_evt(s->scb, strm_tevt_type_proto_err);
  /* fall through */

   return_error:
  /* don't send any error message as we're in the body */
  http_set_term_flags(s);
  http_reply_and_close(s, txn->status, NULL);
  stream_inc_http_fail_ctr(s);
  DBG_TRACE_DEVEL("leaving on error",
      STRM_EV_STRM_ANA|STRM_EV_HTTP_ANA|STRM_EV_HTTP_ERR, s, txn);
  return 0;
}

/* Perform an HTTP redirect based on the information in <rule>. The function
 * returns zero in case of an irrecoverable error such as too large a request
 * to build a valid response, 1 in case of successful redirect (hence the rule
 * is final), or 2 if the rule has to be silently skipped.
 */
int http_apply_redirect_rule(struct redirect_rule *rule, struct stream *s, struct http_txn *txn)
{
  struct channel *req = &s->req;
  struct channel *res = &s->res;
  struct htx *htx;
  struct htx_sl *sl;
  struct buffer *chunk;
  struct ist status, reason, location;
  unsigned int flags;
  int ret = 1;

  chunk = alloc_trash_chunk();
  if (!chunk) {
    if (!(s->flags & SF_ERR_MASK))
      s->flags |= SF_ERR_RESOURCE;
    goto fail;
  }

  /*
   * Create the location
   */
  htx = htxbuf(&req->buf);
  switch(rule->type) {
    case REDIRECT_TYPE_SCHEME: {
      struct http_hdr_ctx ctx;
      struct ist path, host;
      struct http_uri_parser parser;

      host = ist("");
      ctx.blk = NULL;
      if (http_find_header(htx, ist("Host"), &ctx, 0))
        host = ctx.value;

      sl = http_get_stline(htx);
      parser = http_uri_parser_init(htx_sl_req_uri(sl));
      path = http_parse_path(&parser);
      /* build message using path */
      if (isttest(path)) {
        if (rule->flags & REDIRECT_FLAG_DROP_QS) {
          int qs = 0;
          while (qs < path.len) {
            if (*(path.ptr + qs) == '?') {
              path.len = qs;
              break;
            }
            qs++;
          }
        }
      }
      else
        path = ist("/");

      if (rule->rdr_str) { /* this is an old "redirect" rule */
        /* add scheme */
        if (!chunk_memcat(chunk, rule->rdr_str, rule->rdr_len))
          goto fail;
      }
      else {
        /* add scheme with executing log format */
        chunk->data += build_logline(s, chunk->area + chunk->data,
                   chunk->size - chunk->data,
                   &rule->rdr_fmt);
      }
      /* add "://" + host + path */
      if (!chunk_memcat(chunk, "://", 3) ||
          !chunk_memcat(chunk, host.ptr, host.len) ||
          !chunk_memcat(chunk, path.ptr, path.len))
        goto fail;

      /* append a slash at the end of the location if needed and missing */
      if (chunk->data && chunk->area[chunk->data - 1] != '/' &&
          (rule->flags & REDIRECT_FLAG_APPEND_SLASH)) {
        if (chunk->data + 1 >= chunk->size)
          goto fail;
        chunk->area[chunk->data++] = '/';
      }
      break;
    }

    case REDIRECT_TYPE_PREFIX: {
      struct ist path;
      struct http_uri_parser parser;

      sl = http_get_stline(htx);
      parser = http_uri_parser_init(htx_sl_req_uri(sl));
      path = http_parse_path(&parser);
      /* build message using path */
      if (isttest(path)) {
        if (rule->flags & REDIRECT_FLAG_DROP_QS) {
          int qs = 0;
          while (qs < path.len) {
            if (*(path.ptr + qs) == '?') {
              path.len = qs;
              break;
            }
            qs++;
          }
        }
      }
      else
        path = ist("/");

      if (rule->rdr_str) { /* this is an old "redirect" rule */
        /* add prefix. Note that if prefix == "/", we don't want to
         * add anything, otherwise it makes it hard for the user to
         * configure a self-redirection.
         */
        if (rule->rdr_len != 1 || *rule->rdr_str != '/') {
          if (!chunk_memcat(chunk, rule->rdr_str, rule->rdr_len))
            goto fail;
        }
      }
      else {
        /* add prefix with executing log format */
        chunk->data += build_logline(s, chunk->area + chunk->data,
                   chunk->size - chunk->data,
                   &rule->rdr_fmt);
      }

      /* add path */
      if (!chunk_memcat(chunk, path.ptr, path.len))
        goto fail;

      /* append a slash at the end of the location if needed and missing */
      if (chunk->data && chunk->area[chunk->data - 1] != '/' &&
          (rule->flags & REDIRECT_FLAG_APPEND_SLASH)) {
        if (chunk->data + 1 >= chunk->size)
          goto fail;
        chunk->area[chunk->data++] = '/';
      }
      break;
    }
    case REDIRECT_TYPE_LOCATION:
    default:
      if (rule->rdr_str) { /* this is an old "redirect" rule */
        /* add location */
        if (!chunk_memcat(chunk, rule->rdr_str, rule->rdr_len))
          goto fail;
      }
      else {
        /* add location with executing log format */
        size_t len = build_logline(s, chunk->area + chunk->data,
                                   chunk->size - chunk->data,
                                   &rule->rdr_fmt);
        if (!len && (rule->flags & REDIRECT_FLAG_IGNORE_EMPTY)) {
          ret = 2;
          goto out;
        }

        chunk->data += len;
      }

      if (rule->flags & REDIRECT_FLAG_KEEP_QS) {
        struct ist path;
        struct http_uri_parser parser;
        char *ptr, *end;
        char sep = '?';

        ptr = memchr(chunk->area, '?', chunk->data);
        if (ptr != NULL)
          sep = ((ptr+1 != b_tail(chunk)) ? '&' : '\0');

        sl = http_get_stline(htx);
        parser = http_uri_parser_init(htx_sl_req_uri(sl));
        path = http_parse_path(&parser);
        ptr = istptr(path);
        end = istend(path);

        /* look up the '?' */
        do {
          if (ptr == end)
            break;
        } while (*ptr++ != '?');

        if (ptr == end)
          break;
        if (sep != '\0' && !chunk_memcat(chunk, &sep, 1))
          goto fail;
        if (!chunk_memcat(chunk, ptr, end-ptr))
          goto fail;
      }
      break;
  }
  location = ist2(chunk->area, chunk->data);

  /*
   * Create the 30x response
   */
  switch (rule->code) {
    case 308:
      status = ist("308");
      reason = ist("Permanent Redirect");
      break;
    case 307:
      status = ist("307");
      reason = ist("Temporary Redirect");
      break;
    case 303:
      status = ist("303");
      reason = ist("See Other");
      break;
    case 301:
      status = ist("301");
      reason = ist("Moved Permanently");
      break;
    case 302:
    default:
      status = ist("302");
      reason = ist("Found");
      break;
  }

  htx = htx_from_buf(&res->buf);
  /* Trim any possible response */
  channel_htx_truncate(&s->res, htx);
  flags = (HTX_SL_F_IS_RESP|HTX_SL_F_VER_11|HTX_SL_F_XFER_LEN|HTX_SL_F_CLEN|HTX_SL_F_BODYLESS);
  sl = htx_add_stline(htx, HTX_BLK_RES_SL, flags, ist("HTTP/1.1"), status, reason);
  if (!sl)
    goto fail;
  sl->info.res.status = rule->code;
  s->txn.http->status = rule->code;

  if (!htx_add_header(htx, ist("Content-length"), ist("0")) ||
      !htx_add_header(htx, ist("Location"), location))
    goto fail;

  if (rule->code == 302 || rule->code == 303 || rule->code == 307) {
    if (!htx_add_header(htx, ist("Cache-Control"), ist("no-cache")))
      goto fail;
  }

  if (rule->flags & REDIRECT_FLAG_COOKIE_FMT) {
    trash.data = build_logline(s, trash.area, trash.size, &rule->cookie.fmt);
    if (!htx_add_header(htx, ist("Set-Cookie"), ist2(trash.area, trash.data)))
      goto fail;
  }
  else if (isttest(rule->cookie.str)) {
    if (!htx_add_header(htx, ist("Set-Cookie"), rule->cookie.str))
      goto fail;
  }

  if (!htx_add_endof(htx, HTX_BLK_EOH))
    goto fail;

  htx->flags |= HTX_FL_EOM;
  htx_to_buf(htx, &res->buf);

  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_LOCAL;
  http_set_term_flags(s);

  if (!http_forward_proxy_resp(s, 1))
    goto fail;

  if (rule->flags & REDIRECT_FLAG_FROM_REQ) {
    /* let's log the request time */
    s->logs.request_ts = now_ns;
    req->analysers &= AN_REQ_FLT_END;

    /* report it if the request was intercepted by the frontend */
    if (s->sess->fe == s->be && s->sess->fe_tgcounters)
      _HA_ATOMIC_INC(&s->sess->fe_tgcounters->intercepted_req);
  }

  out:
  free_trash_chunk(chunk);
  return ret;

  fail:
  /* If an error occurred, remove the incomplete HTTP response from the
   * buffer */
  channel_htx_truncate(res, htxbuf(&res->buf));
  ret = 0;
  goto out;
}

/* This function filters the request header names to only allow [0-9a-zA-Z-]
 * characters. Depending on the proxy configuration, headers with a name not
 * matching this charset are removed or the request is rejected with a
 * 403-Forbidden response if such name are found. It returns HTTP_RULE_RES_CONT
 * to continue the request processing or HTTP_RULE_RES_DENY if the request is
 * rejected.
 */
static enum rule_result http_req_restrict_header_names(struct stream *s, struct htx *htx, struct proxy *px)
{
  struct htx_blk *blk;
  enum rule_result rule_ret = HTTP_RULE_RES_CONT;

  blk = htx_get_first_blk(htx);
  while (blk) {
    enum htx_blk_type type = htx_get_blk_type(blk);

    if (type == HTX_BLK_HDR) {
      struct ist n = htx_get_blk_name(htx, blk);
      int i, end = istlen(n);

      for (i = 0; i < end; i++) {
        if (!isalnum((unsigned char)n.ptr[i]) && n.ptr[i] != '-') {
          break;
        }
      }

      if (i < end) {
        /* Disallowed character found - block the request or remove the header */
        if (px->options2 & PR_O2_RSTRICT_REQ_HDR_NAMES_BLK)
          goto block;
        blk = htx_remove_blk(htx, blk);
        continue;
      }
    }
    if (type == HTX_BLK_EOH)
      break;

    blk = htx_get_next_blk(htx, blk);
  }
  out:
  return rule_ret;
  block:
  /* Block the request returning a 403-Forbidden response */
  s->txn.http->status = 403;
  rule_ret = HTTP_RULE_RES_DENY;
  goto out;
}

/* Replace all headers matching the name <name>. The header value is replaced if
 * it matches the regex <re>. <str> is used for the replacement. If <full> is
 * set to 1, the full-line is matched and replaced. Otherwise, comma-separated
 * values are evaluated one by one. It returns 0 on success and -1 on error.
 */
int http_replace_hdrs(struct stream* s, struct htx *htx, struct ist name,
         const char *str, struct my_regex *re, int full)
{
  struct http_hdr_ctx ctx;

  ctx.blk = NULL;
  while (http_find_header(htx, name, &ctx, full)) {
    struct buffer *output = get_trash_chunk();

    if (!regex_exec_match2(re, ctx.value.ptr, ctx.value.len, MAX_MATCH, pmatch, 0))
      continue;

    output->data = exp_replace(output->area, output->size, ctx.value.ptr, str, pmatch);
    if (output->data == -1)
      return -1;
    if (!http_replace_header_value(htx, &ctx, ist2(output->area, output->data), 1))
      return -1;
  }
  return 0;
}

/* This function executes one of the set-{method,path,query,uri} actions. It
 * takes the string from the variable 'replace' with length 'len', then modifies
 * the relevant part of the request line accordingly. Then it updates various
 * pointers to the next elements which were moved, and the total buffer length.
 * It finds the action to be performed in p[2], previously filled by function
 * parse_set_req_line(). It returns 0 in case of success, -1 in case of internal
 * error, though this can be revisited when this code is finally exploited.
 *
 * 'action' can be '0' to replace method, '1' to replace path, '2' to replace
 * query string, 3 to replace uri or 4 to replace the path+query.
 *
 * In query string case, the mark question '?' must be set at the start of the
 * string by the caller, event if the replacement query string is empty.
 */
int http_req_replace_stline(int action, const char *replace, int len,
          struct proxy *px, struct stream *s)
{
  struct htx *htx = htxbuf(&s->req.buf);

  switch (action) {
    case 0: // method
      if (!http_replace_req_meth(htx, ist2(replace, len)))
        return -1;
      break;

    case 1: // path
      if (!http_replace_req_path(htx, ist2(replace, len), 0))
        return -1;
      break;

    case 2: // query
      if (!http_replace_req_query(htx, ist2(replace, len)))
        return -1;
      break;

    case 3: // uri
      if (!http_replace_req_uri(htx, ist2(replace, len)))
        return -1;
      break;

    case 4: // path + query
      if (!http_replace_req_path(htx, ist2(replace, len), 1))
        return -1;
      break;

    default:
      return -1;
  }
  return 0;
}

/* This function replace the HTTP status code and the associated message. The
 * variable <status> contains the new status code. This function never fails. It
 * returns 0 in case of success, -1 in case of internal error.
 */
int http_res_set_status(unsigned int status, struct ist reason, struct stream *s)
{
  struct htx *htx = htxbuf(&s->res.buf);
  char *res;

  chunk_reset(&trash);
  res = ultoa_o(status, trash.area, trash.size);
  trash.data = res - trash.area;

  /* Do we have a custom reason format string? */
  if (!isttest(reason)) {
    const char *str = http_get_reason(status);
    reason = ist(str);
  }

  if (!http_replace_res_status(htx, ist2(trash.area, trash.data), reason))
    return -1;
  s->txn.http->status = status;
  return 0;
}

/* Executes the http-request rules <rules> for stream <s>, proxy <px> and
 * transaction <txn>. Returns the verdict of the first rule that prevents
 * further processing of the request (auth, deny, ...), and defaults to
 * HTTP_RULE_RES_STOP if it executed all rules or stopped on an allow, or
 * HTTP_RULE_RES_CONT if the last rule was reached. It may set the TX_CLTARPIT
 * on txn->flags if it encounters a tarpit rule. If <deny_status> is not NULL
 * and a deny/tarpit rule is matched, it will be filled with this rule's deny
 * status.
 */
static enum rule_result http_req_get_intercept_rule(struct proxy *px, struct list *def_rules,
                struct list *rules, struct stream *s)
{
  struct session *sess = strm_sess(s);
  struct http_txn *txn = s->txn.http;
  struct act_rule *rule;
  enum rule_result rule_ret = HTTP_RULE_RES_CONT;
  int act_opts = 0;

  if ((s->scf->flags & SC_FL_ERROR) ||
      ((s->scf->flags & SC_FL_EOS) && proxy_abrt_close_def(px, 1)))
    act_opts |= ACT_OPT_FINAL | ACT_OPT_FINAL_EARLY;

  /* If "the current_rule_list" match the executed rule list, we are in
   * resume condition. If a resume is needed it is always in the action
   * and never in the ACL or converters. In this case, we initialise the
   * current rule, and go to the action execution point.
   */
  if (s->current_rule) {
    int forced = s->flags & SF_RULE_FYIELD;

    rule = s->current_rule;
    s->flags &= ~SF_RULE_FYIELD;
    if (s->current_rule_list == rules || (def_rules && s->current_rule_list == def_rules)) {
      if (forced)
        goto resume_rule;
      goto resume_execution;
    }
  }
  s->current_rule_list = ((!def_rules || s->current_rule_list == def_rules) ? rules : def_rules);

  restart:
  /* start the ruleset evaluation in strict mode */
  txn->req.flags &= ~HTTP_MSGF_SOFT_RW;

  list_for_each_entry(rule, s->current_rule_list, list) {
 resume_rule:
    s->current_rule = rule;

    /* check if budget is exceeded and we need to continue on the next
     * polling loop, unless we know that we cannot yield
     */
    if (s->rules_bcount++ >= global.tune.max_rules_at_once && !(act_opts & ACT_OPT_FINAL)) {
      s->flags |= SF_RULE_FYIELD;
      rule_ret = HTTP_RULE_RES_FYIELD;
      task_wakeup(s->task, TASK_WOKEN_MSG);
      goto end;
    }

    /* check optional condition */
    if (!acl_match_cond(rule->cond, px, sess, s, SMP_OPT_DIR_REQ|SMP_OPT_FINAL))
      continue;

    act_opts |= ACT_OPT_FIRST;
  resume_execution:
    if (rule->kw->flags & KWF_EXPERIMENTAL)
      mark_tainted(TAINTED_ACTION_EXP_EXECUTED);

    /* Always call the action function if defined */
    if (rule->action_ptr) {
      if (!(s->scf->flags & SC_FL_ERROR) && !(s->req.flags & (CF_READ_TIMEOUT|CF_WRITE_TIMEOUT))) {
        s->waiting_entity.type = STRM_ENTITY_NONE;
        s->waiting_entity.ptr  = NULL;
      }

      switch (EXEC_CTX_WITH_RET(rule->exec_ctx,
                                rule->action_ptr(rule, px, sess, s, act_opts))) {
        case ACT_RET_CONT:
          break;
        case ACT_RET_STOP:
          rule_ret = HTTP_RULE_RES_STOP;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_YIELD:
          if (act_opts & ACT_OPT_FINAL) {
            send_log(s->be, LOG_WARNING,
               "Internal error: action yields while it is  no long allowed "
               "for the http-request actions.");
            s->last_entity.type = STRM_ENTITY_RULE;
            s->last_entity.ptr  = rule;
            rule_ret = HTTP_RULE_RES_ERROR;
            goto end;
          }
          s->waiting_entity.type = STRM_ENTITY_RULE;
          s->waiting_entity.ptr  = rule;
          rule_ret = HTTP_RULE_RES_YIELD;
          goto end;
        case ACT_RET_ERR:
          rule_ret = HTTP_RULE_RES_ERROR;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_DONE:
          rule_ret = HTTP_RULE_RES_DONE;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_DENY:
          if (txn->status == -1)
            txn->status = 403;
          rule_ret = HTTP_RULE_RES_DENY;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_ABRT:
          rule_ret = HTTP_RULE_RES_ABRT;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_INV:
          rule_ret = HTTP_RULE_RES_BADREQ;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
      }
      continue; /* eval the next rule */
    }

    /* If not action function defined, check for known actions */
    switch (rule->action) {
      case ACT_ACTION_ALLOW:
        rule_ret = HTTP_RULE_RES_STOP;
        s->last_entity.type = STRM_ENTITY_RULE;
        s->last_entity.ptr  = rule;
        goto end;

      case ACT_ACTION_DENY:
        txn->status = rule->arg.http_reply->status;
        txn->http_reply = rule->arg.http_reply;
        rule_ret = HTTP_RULE_RES_DENY;
        s->last_entity.type = STRM_ENTITY_RULE;
        s->last_entity.ptr  = rule;
        goto end;

      case ACT_HTTP_REQ_TARPIT:
        txn->flags |= TX_CLTARPIT;
        txn->status = rule->arg.http_reply->status;
        txn->http_reply = rule->arg.http_reply;
        rule_ret = HTTP_RULE_RES_DENY;
        s->last_entity.type = STRM_ENTITY_RULE;
        s->last_entity.ptr  = rule;
        goto end;

      case ACT_HTTP_REDIR: {
        int ret = http_apply_redirect_rule(rule->arg.redir, s, txn);

        if (ret == 2) // 2 == skip
          break;

        rule_ret = ret ? HTTP_RULE_RES_ABRT : HTTP_RULE_RES_ERROR;
        s->last_entity.type = STRM_ENTITY_RULE;
        s->last_entity.ptr  = rule;
        goto end;
      }

      /* other flags exists, but normally, they never be matched. */
      default:
        break;
    }
  }

  if (def_rules && s->current_rule_list == def_rules) {
    s->current_rule_list = rules;
    s->current_rule = NULL;
    goto restart;
  }

  end:
  /* if the ruleset evaluation is finished reset the strict mode */
  if (rule_ret != HTTP_RULE_RES_YIELD && rule_ret != HTTP_RULE_RES_FYIELD) {
    s->current_rule_list = NULL;
    s->current_rule = NULL;
    txn->req.flags &= ~HTTP_MSGF_SOFT_RW;
  }

  /* we reached the end of the rules, nothing to report */
  return rule_ret;
}

/* Executes the http-response rules <rules> for stream <s> and proxy <px>. It
 * returns one of 6 possible statuses: HTTP_RULE_RES_CONT, HTTP_RULE_RES_STOP,
 * HTTP_RULE_RES_DONE, HTTP_RULE_RES_(F)YIELD, or HTTP_RULE_RES_BADREQ. If *CONT
 * is returned, the process can continue the evaluation of next rule list. If
 * *STOP or *DONE is returned, the process must stop the evaluation. If *BADREQ
 * is returned, it means the operation could not be processed and a server error
 * must be returned. If *YIELD is returned, the caller must call again the
 * function with the same context.
 */
static enum rule_result http_res_get_intercept_rule(struct proxy *px, struct list *def_rules,
                struct list *rules, struct stream *s, uint8_t final)
{
  struct session *sess = strm_sess(s);
  struct http_txn *txn = s->txn.http;
  struct act_rule *rule;
  enum rule_result rule_ret = HTTP_RULE_RES_CONT;
  int act_opts = 0;

  if (final)
    act_opts |= ACT_OPT_FINAL;
  if ((s->scf->flags & SC_FL_ERROR) ||
      ((s->scf->flags & SC_FL_EOS) && proxy_abrt_close_def(px, 1)))
    act_opts |= ACT_OPT_FINAL | ACT_OPT_FINAL_EARLY;

  /* If "the current_rule_list" match the executed rule list, we are in
   * resume condition. If a resume is needed it is always in the action
   * and never in the ACL or converters. In this case, we initialise the
   * current rule, and go to the action execution point.
   */
  if (s->current_rule) {
    int forced = s->flags & SF_RULE_FYIELD;

    rule = s->current_rule;
    s->flags &= ~SF_RULE_FYIELD;
    if (s->current_rule_list == rules || (def_rules && s->current_rule_list == def_rules)) {
      if (forced)
        goto resume_rule;
      goto resume_execution;
    }
  }
  s->current_rule_list = ((!def_rules || s->current_rule_list == def_rules) ? rules : def_rules);

  restart:

  /* start the ruleset evaluation in strict mode */
  txn->rsp.flags &= ~HTTP_MSGF_SOFT_RW;

  list_for_each_entry(rule, s->current_rule_list, list) {
 resume_rule:
    s->current_rule = rule;

    /* check if budget is exceeded and we need to continue on the next
     * polling loop, unless we know that we cannot yield
     */
    if (s->rules_bcount++ >= global.tune.max_rules_at_once && !(act_opts & ACT_OPT_FINAL)) {
      s->flags |= SF_RULE_FYIELD;
      rule_ret = HTTP_RULE_RES_FYIELD;
      task_wakeup(s->task, TASK_WOKEN_MSG);
      goto end;
    }

    /* check optional condition */
    if (!acl_match_cond(rule->cond, px, sess, s, SMP_OPT_DIR_RES|SMP_OPT_FINAL))
      continue;

    act_opts |= ACT_OPT_FIRST;
resume_execution:
    if (rule->kw->flags & KWF_EXPERIMENTAL)
      mark_tainted(TAINTED_ACTION_EXP_EXECUTED);

    /* Always call the action function if defined */
    if (rule->action_ptr) {
      if (!(s->scb->flags & SC_FL_ERROR) && !(s->res.flags & (CF_READ_TIMEOUT|CF_WRITE_TIMEOUT))) {
        s->waiting_entity.type = STRM_ENTITY_NONE;
        s->waiting_entity.ptr  = NULL;
      }

      switch (EXEC_CTX_WITH_RET(rule->exec_ctx,
                                rule->action_ptr(rule, px, sess, s, act_opts))) {
        case ACT_RET_CONT:
          break;
        case ACT_RET_STOP:
          rule_ret = HTTP_RULE_RES_STOP;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_YIELD:
          if (act_opts & ACT_OPT_FINAL) {
            send_log(s->be, LOG_WARNING,
               "Internal error: action yields while it is no long allowed "
               "for the http-response/http-after-response actions.");
            s->last_entity.type = STRM_ENTITY_RULE;
            s->last_entity.ptr  = rule;
            rule_ret = HTTP_RULE_RES_ERROR;
            goto end;
          }
          s->waiting_entity.type = STRM_ENTITY_RULE;
          s->waiting_entity.ptr  = rule;
          rule_ret = HTTP_RULE_RES_YIELD;
          goto end;
        case ACT_RET_ERR:
          rule_ret = HTTP_RULE_RES_ERROR;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_DONE:
          rule_ret = HTTP_RULE_RES_DONE;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_DENY:
          if (txn->status == -1)
            txn->status = 502;
          rule_ret = HTTP_RULE_RES_DENY;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_ABRT:
          rule_ret = HTTP_RULE_RES_ABRT;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
        case ACT_RET_INV:
          rule_ret = HTTP_RULE_RES_BADREQ;
          s->last_entity.type = STRM_ENTITY_RULE;
          s->last_entity.ptr  = rule;
          goto end;
      }
      continue; /* eval the next rule */
    }

    /* If not action function defined, check for known actions */
    switch (rule->action) {
      case ACT_ACTION_ALLOW:
        rule_ret = HTTP_RULE_RES_STOP; /* "allow" rules are OK */
        s->last_entity.type = STRM_ENTITY_RULE;
        s->last_entity.ptr  = rule;
        goto end;

      case ACT_ACTION_DENY:
        txn->status = rule->arg.http_reply->status;
        txn->http_reply = rule->arg.http_reply;
        rule_ret = HTTP_RULE_RES_DENY;
        s->last_entity.type = STRM_ENTITY_RULE;
        s->last_entity.ptr  = rule;
        goto end;

      case ACT_HTTP_REDIR: {
        int ret = http_apply_redirect_rule(rule->arg.redir, s, txn);

        if (ret == 2) // 2 == skip
          break;

        rule_ret = ret ? HTTP_RULE_RES_ABRT : HTTP_RULE_RES_ERROR;
        s->last_entity.type = STRM_ENTITY_RULE;
        s->last_entity.ptr  = rule;
        goto end;
      }
      /* other flags exists, but normally, they never be matched. */
      default:
        break;
    }
  }

  if (def_rules && s->current_rule_list == def_rules) {
    s->current_rule_list = rules;
    s->current_rule = NULL;
    goto restart;
  }

  end:
  /* if the ruleset evaluation is finished reset the strict mode */
  if (rule_ret != HTTP_RULE_RES_YIELD && rule_ret != HTTP_RULE_RES_FYIELD) {
    s->current_rule_list = NULL;
    s->current_rule = NULL;
    txn->rsp.flags &= ~HTTP_MSGF_SOFT_RW;
  }

  /* we reached the end of the rules, nothing to report */
  return rule_ret;
}

/* Executes backend and frontend http-after-response rules for the stream <s>,
 * in that order. it return 1 on success and 0 on error. It is the caller
 * responsibility to catch error or ignore it. If it catches it, this function
 * may be called a second time, for the internal error.
 */
int http_eval_after_res_rules(struct stream *s)
{
  struct list *def_rules, *rules;
  struct session *sess = s->sess;
  enum rule_result ret = HTTP_RULE_RES_CONT;

  /* Eval after-response ruleset only if the reply is not const */
  if (s->txn.http->flags & TX_CONST_REPLY)
    goto end;

  /* prune the request variables if not already done and swap to the response variables. */
  if (s->vars_reqres.scope != SCOPE_RES) {
    vars_prune(&s->vars_reqres, s->sess, s);
    vars_init_head(&s->vars_reqres, SCOPE_RES);
  }

  def_rules = (s->be->defpx ? &s->be->defpx->http_after_res_rules : NULL);
  rules = &s->be->http_after_res_rules;

  ret = http_res_get_intercept_rule(s->be, def_rules, rules, s, 1);
  if ((ret == HTTP_RULE_RES_CONT || ret == HTTP_RULE_RES_STOP) && sess->fe != s->be) {
    def_rules = ((sess->fe->defpx && sess->fe->defpx != s->be->defpx) ? &sess->fe->defpx->http_after_res_rules : NULL);
    rules = &sess->fe->http_after_res_rules;
    ret = http_res_get_intercept_rule(sess->fe, def_rules, rules, s, 1);
  }

  end:
  /* All other codes than CONTINUE, STOP or DONE are forbidden */
  return (ret == HTTP_RULE_RES_CONT || ret == HTTP_RULE_RES_STOP || ret == HTTP_RULE_RES_DONE);
}

/*
 * Manage client-side cookie. It can impact performance by about 2% so it is
 * desirable to call it only when needed. This code is quite complex because
 * of the multiple very crappy and ambiguous syntaxes we have to support. it
 * highly recommended not to touch this part without a good reason !
 */
static void http_manage_client_side_cookies(struct stream *s, struct channel *req)
{
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct htx *htx;
  struct http_hdr_ctx ctx;
  char *hdr_beg, *hdr_end, *del_from;
  char *prev, *att_beg, *att_end, *equal, *val_beg, *val_end, *next;
  int preserve_hdr;

  htx = htxbuf(&req->buf);
  ctx.blk = NULL;
  while (http_find_header(htx, ist("Cookie"), &ctx, 1)) {
    int is_first = 1;
    del_from = NULL;  /* nothing to be deleted */
    preserve_hdr = 0; /* assume we may kill the whole header */

    /* Now look for cookies. Conforming to RFC2109, we have to support
     * attributes whose name begin with a '$', and associate them with
     * the right cookie, if we want to delete this cookie.
     * So there are 3 cases for each cookie read :
     * 1) it's a special attribute, beginning with a '$' : ignore it.
     * 2) it's a server id cookie that we *MAY* want to delete : save
     *    some pointers on it (last semi-colon, beginning of cookie...)
     * 3) it's an application cookie : we *MAY* have to delete a previous
     *    "special" cookie.
     * At the end of loop, if a "special" cookie remains, we may have to
     * remove it. If no application cookie persists in the header, we
     * *MUST* delete it.
     *
     * Note: RFC2965 is unclear about the processing of spaces around
     * the equal sign in the ATTR=VALUE form. A careful inspection of
     * the RFC explicitly allows spaces before it, and not within the
     * tokens (attrs or values). An inspection of RFC2109 allows that
     * too but section 10.1.3 lets one think that spaces may be allowed
     * after the equal sign too, resulting in some (rare) buggy
     * implementations trying to do that. So let's do what servers do.
     * Latest ietf draft forbids spaces all around. Also, earlier RFCs
     * allowed quoted strings in values, with any possible character
     * after a backslash, including control chars and delimiters, which
     * causes parsing to become ambiguous. Browsers also allow spaces
     * within values even without quotes.
     *
     * We have to keep multiple pointers in order to support cookie
     * removal at the beginning, middle or end of header without
     * corrupting the header. All of these headers are valid :
     *
     * hdr_beg                                               hdr_end
     * |                                                        |
     * v                                                        |
     * NAME1=VALUE1;NAME2=VALUE2;NAME3=VALUE3                   |
     * NAME1=VALUE1;NAME2_ONLY ;NAME3=VALUE3                    v
     *      NAME1  =  VALUE 1  ; NAME2 = VALUE2 ; NAME3 = VALUE3
     * |    |    | |  |      | |
     * |    |    | |  |      | |
     * |    |    | |  |      | +--> next
     * |    |    | |  |      +----> val_end
     * |    |    | |  +-----------> val_beg
     * |    |    | +--------------> equal
     * |    |    +----------------> att_end
     * |    +---------------------> att_beg
     * +--------------------------> prev
     *
     */
    hdr_beg = ctx.value.ptr;
    hdr_end = hdr_beg + ctx.value.len;
    for (prev = hdr_beg; prev < hdr_end; prev = next) {
      /* Iterate through all cookies on this line */

      /* find att_beg */
      att_beg = prev;
      if (!is_first)
        att_beg++;
      is_first = 0;

      while (att_beg < hdr_end && HTTP_IS_SPHT(*att_beg))
        att_beg++;

      /* find att_end : this is the first character after the last non
       * space before the equal. It may be equal to hdr_end.
       */
      equal = att_end = att_beg;
      while (equal < hdr_end) {
        if (*equal == '=' || *equal == ',' || *equal == ';')
          break;
        if (HTTP_IS_SPHT(*equal++))
          continue;
        att_end = equal;
      }

      /* here, <equal> points to '=', a delimiter or the end. <att_end>
       * is between <att_beg> and <equal>, both may be identical.
       */
      /* look for end of cookie if there is an equal sign */
      if (equal < hdr_end && *equal == '=') {
        /* look for the beginning of the value */
        val_beg = equal + 1;
        while (val_beg < hdr_end && HTTP_IS_SPHT(*val_beg))
          val_beg++;

        /* find the end of the value, respecting quotes */
        next = http_find_cookie_value_end(val_beg, hdr_end);

        /* make val_end point to the first white space or delimiter after the value */
        val_end = next;
        while (val_end > val_beg && HTTP_IS_SPHT(*(val_end - 1)))
          val_end--;
      }
      else
        val_beg = val_end = next = equal;

      /* We have nothing to do with attributes beginning with
       * '$'. However, they will automatically be removed if a
       * header before them is removed, since they're supposed
       * to be linked together.
       */
      if (*att_beg == '$')
        continue;

      /* Ignore cookies with no equal sign */
      if (equal == next) {
        /* This is not our cookie, so we must preserve it. But if we already
         * scheduled another cookie for removal, we cannot remove the
         * complete header, but we can remove the previous block itself.
         */
        preserve_hdr = 1;
        if (del_from != NULL) {
          int delta = http_del_hdr_value(hdr_beg, hdr_end, &del_from, prev);
          val_end  += delta;
          next     += delta;
          hdr_end  += delta;
          prev     = del_from;
          del_from = NULL;
        }
        continue;
      }

      /* if there are spaces around the equal sign, we need to
       * strip them otherwise we'll get trouble for cookie captures,
       * or even for rewrites. Since this happens extremely rarely,
       * it does not hurt performance.
       */
      if (unlikely(att_end != equal || val_beg > equal + 1)) {
        int stripped_before = 0;
        int stripped_after = 0;

        if (att_end != equal) {
          memmove(att_end, equal, hdr_end - equal);
          stripped_before = (att_end - equal);
          equal   += stripped_before;
          val_beg += stripped_before;
        }

        if (val_beg > equal + 1) {
          memmove(equal + 1, val_beg, hdr_end + stripped_before - val_beg);
          stripped_after = (equal + 1) - val_beg;
          val_beg += stripped_after;
          stripped_before += stripped_after;
        }

        val_end      += stripped_before;
        next         += stripped_before;
        hdr_end      += stripped_before;
      }
      /* now everything is as on the diagram above */

      /* First, let's see if we want to capture this cookie. We check
       * that we don't already have a client side cookie, because we
       * can only capture one. Also as an optimisation, we ignore
       * cookies shorter than the declared name.
       */
      if (sess->fe->capture_name != NULL && txn->cli_cookie == NULL &&
          (val_end - att_beg >= sess->fe->capture_namelen) &&
          memcmp(att_beg, sess->fe->capture_name, sess->fe->capture_namelen) == 0) {
        int log_len = val_end - att_beg;

        if ((txn->cli_cookie = pool_alloc(pool_head_capture)) == NULL) {
          ha_alert("HTTP logging : out of memory.\n");
        } else {
          if (log_len > sess->fe->capture_len)
            log_len = sess->fe->capture_len;
          memcpy(txn->cli_cookie, att_beg, log_len);
          txn->cli_cookie[log_len] = 0;
        }
      }

      /* Persistence cookies in passive, rewrite or insert mode have the
       * following form :
       *
       *    Cookie: NAME=SRV[|<lastseen>[|<firstseen>]]
       *
       * For cookies in prefix mode, the form is :
       *
       *    Cookie: NAME=SRV~VALUE
       */
      if ((att_end - att_beg == s->be->cookie_len) && (s->be->cookie_name != NULL) &&
          (memcmp(att_beg, s->be->cookie_name, att_end - att_beg) == 0)) {
        struct server *srv = s->be->srv;
        char *delim;

        /* if we're in cookie prefix mode, we'll search the delimiter so that we
         * have the server ID between val_beg and delim, and the original cookie between
         * delim+1 and val_end. Otherwise, delim==val_end :
         *
         * hdr_beg
         * |
         * v
         * NAME=SRV;          # in all but prefix modes
         * NAME=SRV~OPAQUE ;  # in prefix mode
         * ||   ||  |      |+-> next
         * ||   ||  |      +--> val_end
         * ||   ||  +---------> delim
         * ||   |+------------> val_beg
         * ||   +-------------> att_end = equal
         * |+-----------------> att_beg
         * +------------------> prev
         *
         */
        if (s->be->ck_opts & PR_CK_PFX) {
          for (delim = val_beg; delim < val_end; delim++)
            if (*delim == COOKIE_DELIM)
              break;
        }
        else {
          char *vbar1;
          delim = val_end;
          /* Now check if the cookie contains a date field, which would
           * appear after a vertical bar ('|') just after the server name
           * and before the delimiter.
           */
          vbar1 = memchr(val_beg, COOKIE_DELIM_DATE, val_end - val_beg);
          if (vbar1) {
            /* OK, so left of the bar is the server's cookie and
             * right is the last seen date. It is a base64 encoded
             * 30-bit value representing the UNIX date since the
             * epoch in 4-second quantities.
             */
            int val;
            delim = vbar1++;
            if (val_end - vbar1 >= 5) {
              val = b64tos30(vbar1);
              if (val > 0)
                txn->cookie_last_date = val << 2;
            }
            /* look for a second vertical bar */
            vbar1 = memchr(vbar1, COOKIE_DELIM_DATE, val_end - vbar1);
            if (vbar1 && (val_end - vbar1 > 5)) {
              val = b64tos30(vbar1 + 1);
              if (val > 0)
                txn->cookie_first_date = val << 2;
            }
          }
        }

        /* if the cookie has an expiration date and the proxy wants to check
         * it, then we do that now. We first check if the cookie is too old,
         * then only if it has expired. We detect strict overflow because the
         * time resolution here is not great (4 seconds). Cookies with dates
         * in the future are ignored if their offset is beyond one day. This
         * allows an admin to fix timezone issues without expiring everyone
         * and at the same time avoids keeping unwanted side effects for too
         * long.
         */
        if (txn->cookie_first_date && s->be->cookie_maxlife &&
            (((signed)(date.tv_sec - txn->cookie_first_date) > (signed)s->be->cookie_maxlife) ||
             ((signed)(txn->cookie_first_date - date.tv_sec) > 86400))) {
          txn->flags &= ~TX_CK_MASK;
          txn->flags |= TX_CK_OLD;
          delim = val_beg; // let's pretend we have not found the cookie
          txn->cookie_first_date = 0;
          txn->cookie_last_date = 0;
        }
        else if (txn->cookie_last_date && s->be->cookie_maxidle &&
           (((signed)(date.tv_sec - txn->cookie_last_date) > (signed)s->be->cookie_maxidle) ||
            ((signed)(txn->cookie_last_date - date.tv_sec) > 86400))) {
          txn->flags &= ~TX_CK_MASK;
          txn->flags |= TX_CK_EXPIRED;
          delim = val_beg; // let's pretend we have not found the cookie
          txn->cookie_first_date = 0;
          txn->cookie_last_date = 0;
        }

        /* Here, we'll look for the first running server which supports the cookie.
         * This allows to share a same cookie between several servers, for example
         * to dedicate backup servers to specific servers only.
         * However, to prevent clients from sticking to cookie-less backup server
         * when they have incidentely learned an empty cookie, we simply ignore
         * empty cookies and mark them as invalid.
         * The same behaviour is applied when persistence must be ignored.
         */
        if ((delim == val_beg) || (s->flags & (SF_IGNORE_PRST | SF_ASSIGNED)))
          srv = NULL;

        while (srv) {
          if (srv->cookie && (srv->cklen == delim - val_beg) &&
              !memcmp(val_beg, srv->cookie, delim - val_beg)) {
            if ((srv->cur_state != SRV_ST_STOPPED) ||
                (s->be->options & PR_O_PERSIST) ||
                (s->flags & SF_FORCE_PRST)) {
              /* we found the server and we can use it */
              txn->flags &= ~TX_CK_MASK;
              txn->flags |= (srv->cur_state != SRV_ST_STOPPED) ? TX_CK_VALID : TX_CK_DOWN;
              s->flags |= SF_DIRECT | SF_ASSIGNED;
              stream_set_srv_target(s, srv);
              break;
            } else {
              /* we found a server, but it's down,
               * mark it as such and go on in case
               * another one is available.
               */
              txn->flags &= ~TX_CK_MASK;
              txn->flags |= TX_CK_DOWN;
            }
          }
          srv = srv->next;
        }

        if (!srv && !(txn->flags & (TX_CK_DOWN|TX_CK_EXPIRED|TX_CK_OLD))) {
          /* no server matched this cookie or we deliberately skipped it */
          txn->flags &= ~TX_CK_MASK;
          if ((s->flags & (SF_IGNORE_PRST | SF_ASSIGNED)))
            txn->flags |= TX_CK_UNUSED;
          else
            txn->flags |= TX_CK_INVALID;
        }

        /* depending on the cookie mode, we may have to either :
         * - delete the complete cookie if we're in insert+indirect mode, so that
         *   the server never sees it ;
         * - remove the server id from the cookie value, and tag the cookie as an
         *   application cookie so that it does not get accidentally removed later,
         *   if we're in cookie prefix mode
         */
        if ((s->be->ck_opts & PR_CK_PFX) && (delim != val_end)) {
          int delta; /* negative */

          memmove(val_beg, delim + 1, hdr_end - (delim + 1));
          delta = val_beg - (delim + 1);
          val_end  += delta;
          next     += delta;
          hdr_end  += delta;
          del_from = NULL;
          preserve_hdr = 1; /* we want to keep this cookie */
        }
        else if (del_from == NULL &&
           (s->be->ck_opts & (PR_CK_INS | PR_CK_IND)) == (PR_CK_INS | PR_CK_IND)) {
          del_from = prev;
        }
      }
      else {
        /* This is not our cookie, so we must preserve it. But if we already
         * scheduled another cookie for removal, we cannot remove the
         * complete header, but we can remove the previous block itself.
         */
        preserve_hdr = 1;

        if (del_from != NULL) {
          int delta = http_del_hdr_value(hdr_beg, hdr_end, &del_from, prev);
          if (att_beg >= del_from)
            att_beg += delta;
          if (att_end >= del_from)
            att_end += delta;
          val_beg  += delta;
          val_end  += delta;
          next     += delta;
          hdr_end  += delta;
          prev     = del_from;
          del_from = NULL;
        }
      }

    } /* for each cookie */


    /* There are no more cookies on this line.
     * We may still have one (or several) marked for deletion at the
     * end of the line. We must do this now in two ways :
     *  - if some cookies must be preserved, we only delete from the
     *    mark to the end of line ;
     *  - if nothing needs to be preserved, simply delete the whole header
     */
    if (del_from) {
      hdr_end = (preserve_hdr ? del_from : hdr_beg);
    }
    if ((hdr_end - hdr_beg) != ctx.value.len) {
      if (hdr_beg != hdr_end)
        htx_change_blk_value_len(htx, ctx.blk, hdr_end - hdr_beg);
      else
        http_remove_header(htx, &ctx);
    }
  } /* for each "Cookie header */
}

/*
 * Manage server-side cookies. It can impact performance by about 2% so it is
 * desirable to call it only when needed. This function is also used when we
 * just need to know if there is a cookie (eg: for check-cache).
 */
static void http_manage_server_side_cookies(struct stream *s, struct channel *res)
{
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct htx *htx;
  struct http_hdr_ctx ctx;
  struct server *srv;
  char *hdr_beg, *hdr_end;
  char *prev, *att_beg, *att_end, *equal, *val_beg, *val_end, *next;

  htx = htxbuf(&res->buf);

  ctx.blk = NULL;
  while (http_find_header(htx, ist("Set-Cookie"), &ctx, 1)) {
    int is_first = 1;

    /* OK, right now we know we have a Set-Cookie* at hdr_beg, and
     * <prev> points to the colon.
     */
    txn->flags |= TX_SCK_PRESENT;

    /* Maybe we only wanted to see if there was a Set-Cookie (eg:
     * check-cache is enabled) and we are not interested in checking
     * them. Warning, the cookie capture is declared in the frontend.
     */
    if (s->be->cookie_name == NULL && sess->fe->capture_name == NULL)
      break;

    /* OK so now we know we have to process this response cookie.
     * The format of the Set-Cookie header is slightly different
     * from the format of the Cookie header in that it does not
     * support the comma as a cookie delimiter (thus the header
     * cannot be folded) because the Expires attribute described in
     * the original Netscape's spec may contain an unquoted date
     * with a comma inside. We have to live with this because
     * many browsers don't support Max-Age and some browsers don't
     * support quoted strings. However the Set-Cookie2 header is
     * clean but basically nobody supports it.
     *
     * We have to keep multiple pointers in order to support cookie
     * removal at the beginning, middle or end of header without
     * corrupting the header (in case of set-cookie2). A special
     * pointer, <scav> points to the beginning of the set-cookie-av
     * fields after the first semi-colon. The <next> pointer points
     * either to the end of line (set-cookie) or next unquoted comma
     * (set-cookie2). All of these headers are valid :
     *
     * hdr_beg                                                  hdr_end
     * |                                                           |
     * v                                                           |
     * NAME1  =  VALUE 1  ; Secure; Path="/"                       |
     * NAME=VALUE; Secure; Expires=Thu, 01-Jan-1970 00:00:01 GMT   v
     * NAME = VALUE ; Secure; Expires=Thu, 01-Jan-1970 00:00:01 GMT
     * NAME1 = VALUE 1 ; Max-Age=0, NAME2=VALUE2; Discard
     * | |   | | |     | |          |
     * | |   | | |     | |          +-> next
     * | |   | | |     | +------------> scav
     * | |   | | |     +--------------> val_end
     * | |   | | +--------------------> val_beg
     * | |   | +----------------------> equal
     * | |   +------------------------> att_end
     * | +----------------------------> att_beg
     * +------------------------------> prev
     * -------------------------------> hdr_beg
     */
    hdr_beg = ctx.value.ptr;
    hdr_end = hdr_beg + ctx.value.len;
    for (prev = hdr_beg; prev < hdr_end; prev = next) {

      /* Iterate through all cookies on this line */

      /* find att_beg */
      att_beg = prev;
      if (!is_first)
        att_beg++;
      is_first = 0;

      while (att_beg < hdr_end && HTTP_IS_SPHT(*att_beg))
        att_beg++;

      /* find att_end : this is the first character after the last non
       * space before the equal. It may be equal to hdr_end.
       */
      equal = att_end = att_beg;

      while (equal < hdr_end) {
        if (*equal == '=' || *equal == ';')
          break;
        if (HTTP_IS_SPHT(*equal++))
          continue;
        att_end = equal;
      }

      /* here, <equal> points to '=', a delimiter or the end. <att_end>
       * is between <att_beg> and <equal>, both may be identical.
       */

      /* look for end of cookie if there is an equal sign */
      if (equal < hdr_end && *equal == '=') {
        /* look for the beginning of the value */
        val_beg = equal + 1;
        while (val_beg < hdr_end && HTTP_IS_SPHT(*val_beg))
          val_beg++;

        /* find the end of the value, respecting quotes */
        next = http_find_cookie_value_end(val_beg, hdr_end);

        /* make val_end point to the first white space or delimiter after the value */
        val_end = next;
        while (val_end > val_beg && HTTP_IS_SPHT(*(val_end - 1)))
          val_end--;
      }
      else {
        /* <equal> points to next comma, semi-colon or EOL */
        val_beg = val_end = next = equal;
      }

      if (next < hdr_end) {
        /* For Set-Cookie, since commas are permitted
         * in values, skip to the end.
         */
        next = hdr_end;
      }

      /* Now everything is as on the diagram above */

      /* Ignore cookies with no equal sign */
      if (equal == val_end)
        continue;

      /* If there are spaces around the equal sign, we need to
       * strip them otherwise we'll get trouble for cookie captures,
       * or even for rewrites. Since this happens extremely rarely,
       * it does not hurt performance.
       */
      if (unlikely(att_end != equal || val_beg > equal + 1)) {
        int stripped_before = 0;
        int stripped_after = 0;

        if (att_end != equal) {
          memmove(att_end, equal, hdr_end - equal);
          stripped_before = (att_end - equal);
          equal   += stripped_before;
          val_beg += stripped_before;
        }

        if (val_beg > equal + 1) {
          memmove(equal + 1, val_beg, hdr_end + stripped_before - val_beg);
          stripped_after = (equal + 1) - val_beg;
          val_beg += stripped_after;
          stripped_before += stripped_after;
        }

        val_end      += stripped_before;
        next         += stripped_before;
        hdr_end      += stripped_before;

        htx_change_blk_value_len(htx, ctx.blk, hdr_end - hdr_beg);
        ctx.value.len = hdr_end - hdr_beg;
      }

      /* First, let's see if we want to capture this cookie. We check
       * that we don't already have a server side cookie, because we
       * can only capture one. Also as an optimisation, we ignore
       * cookies shorter than the declared name.
       */
      if (sess->fe->capture_name != NULL &&
          txn->srv_cookie == NULL &&
          (val_end - att_beg >= sess->fe->capture_namelen) &&
          memcmp(att_beg, sess->fe->capture_name, sess->fe->capture_namelen) == 0) {
        int log_len = val_end - att_beg;
        if ((txn->srv_cookie = pool_alloc(pool_head_capture)) == NULL) {
          ha_alert("HTTP logging : out of memory.\n");
        }
        else {
          if (log_len > sess->fe->capture_len)
            log_len = sess->fe->capture_len;
          memcpy(txn->srv_cookie, att_beg, log_len);
          txn->srv_cookie[log_len] = 0;
        }
      }

      srv = objt_server(s->target);
      /* now check if we need to process it for persistence */
      if (!(s->flags & SF_IGNORE_PRST) &&
          (att_end - att_beg == s->be->cookie_len) && (s->be->cookie_name != NULL) &&
          (memcmp(att_beg, s->be->cookie_name, att_end - att_beg) == 0)) {
        /* assume passive cookie by default */
        txn->flags &= ~TX_SCK_MASK;
        txn->flags |= TX_SCK_FOUND;

        /* If the cookie is in insert mode on a known server, we'll delete
         * this occurrence because we'll insert another one later.
         * We'll delete it too if the "indirect" option is set and we're in
         * a direct access.
         */
        if (s->be->ck_opts & PR_CK_PSV) {
          /* The "preserve" flag was set, we don't want to touch the
           * server's cookie.
           */
        }
        else if ((srv && (s->be->ck_opts & PR_CK_INS)) ||
            ((s->flags & SF_DIRECT) && (s->be->ck_opts & PR_CK_IND))) {
          /* this cookie must be deleted */
          if (prev == hdr_beg && next == hdr_end) {
            /* whole header */
            http_remove_header(htx, &ctx);
            /* note: while both invalid now, <next> and <hdr_end>
             * are still equal, so the for() will stop as expected.
             */
          } else {
            /* just remove the value */
            int delta = http_del_hdr_value(hdr_beg, hdr_end, &prev, next);
            next      = prev;
            hdr_end  += delta;
          }
          txn->flags &= ~TX_SCK_MASK;
          txn->flags |= TX_SCK_DELETED;
          /* and go on with next cookie */
        }
        else if (srv && srv->cookie && (s->be->ck_opts & PR_CK_RW)) {
          /* replace bytes val_beg->val_end with the cookie name associated
           * with this server since we know it.
           */
          int sliding, delta;

          ctx.value = ist2(val_beg, val_end - val_beg);
                ctx.lws_before = ctx.lws_after = 0;
          http_replace_header_value(htx, &ctx, ist2(srv->cookie, srv->cklen), 0);
          delta     = srv->cklen - (val_end - val_beg);
          sliding   = (ctx.value.ptr - val_beg);
          hdr_beg  += sliding;
          val_beg  += sliding;
          next     += sliding + delta;
          hdr_end  += sliding + delta;

          txn->flags &= ~TX_SCK_MASK;
          txn->flags |= TX_SCK_REPLACED;
        }
        else if (srv && srv->cookie && (s->be->ck_opts & PR_CK_PFX)) {
          /* insert the cookie name associated with this server
           * before existing cookie, and insert a delimiter between them..
           */
          int sliding, delta;
          ctx.value = ist2(val_beg, 0);
                ctx.lws_before = ctx.lws_after = 0;
          http_replace_header_value(htx, &ctx, ist2(srv->cookie, srv->cklen + 1), 0);
          delta     = srv->cklen + 1;
          sliding   = (ctx.value.ptr - val_beg);
          hdr_beg  += sliding;
          val_beg  += sliding;
          next     += sliding + delta;
          hdr_end  += sliding + delta;

          val_beg[srv->cklen] = COOKIE_DELIM;
          txn->flags &= ~TX_SCK_MASK;
          txn->flags |= TX_SCK_REPLACED;
        }
      }
      /* that's done for this cookie, check the next one on the same
       * line when next != hdr_end (which should normally not happen
       * with set-cookie2 support removed).
       */
    }
  }
}

/*
 * Parses the Cache-Control and Pragma request header fields to determine if
 * the request may be served from the cache and/or if it is cacheable. Updates
 * s->txn.http->flags.
 */
void http_check_request_for_cacheability(struct stream *s, struct channel *req)
{
  struct http_txn *txn = s->txn.http;
  struct htx *htx;
  struct http_hdr_ctx ctx = { .blk = NULL };
  int pragma_found, cc_found;

  if ((txn->flags & (TX_CACHEABLE|TX_CACHE_IGNORE)) == TX_CACHE_IGNORE)
    return; /* nothing more to do here */

  htx = htxbuf(&req->buf);
  pragma_found = cc_found = 0;

  /* Check "pragma" header for HTTP/1.0 compatibility. */
  if (http_find_header(htx, ist("pragma"), &ctx, 1)) {
    if (isteqi(ctx.value, ist("no-cache"))) {
      pragma_found = 1;
    }
  }

  ctx.blk = NULL;
  /* Don't use the cache and don't try to store if we found the
   * Authorization header */
  if (http_find_header(htx, ist("authorization"), &ctx, 1)) {
    txn->flags &= ~TX_CACHEABLE & ~TX_CACHE_COOK;
    txn->flags |= TX_CACHE_IGNORE;
  }


  /* Look for "cache-control" header and iterate over all the values
   * until we find one that specifies that caching is possible or not. */
  ctx.blk = NULL;
  while (http_find_header(htx, ist("cache-control"), &ctx, 0)) {
    cc_found = 1;
    /* We don't check the values after max-age, max-stale nor min-fresh,
     * we simply don't use the cache when they're specified. */
    if (istmatchi(ctx.value, ist("max-age")) ||
        istmatchi(ctx.value, ist("no-cache")) ||
        istmatchi(ctx.value, ist("max-stale")) ||
        istmatchi(ctx.value, ist("min-fresh"))) {
      txn->flags |= TX_CACHE_IGNORE;
      continue;
    }
    if (istmatchi(ctx.value, ist("no-store"))) {
      txn->flags &= ~TX_CACHEABLE & ~TX_CACHE_COOK;
      continue;
    }
  }

  /* RFC7234#5.4:
   *   When the Cache-Control header field is also present and
   *   understood in a request, Pragma is ignored.
   *   When the Cache-Control header field is not present in a
   *   request, caches MUST consider the no-cache request
   *   pragma-directive as having the same effect as if
   *   "Cache-Control: no-cache" were present.
   */
  if (!cc_found && pragma_found)
    txn->flags |= TX_CACHE_IGNORE;
}

/*
 * Check if response is cacheable or not. Updates s->txn.http->flags.
 */
void http_check_response_for_cacheability(struct stream *s, struct channel *res)
{
  struct http_txn *txn = s->txn.http;
  struct http_hdr_ctx ctx = { .blk = NULL };
  struct htx *htx;
  int has_freshness_info = 0;
  int has_validator = 0;
  int has_null_maxage = 0;

  if (txn->status < 200) {
    /* do not try to cache interim responses! */
    txn->flags &= ~TX_CACHEABLE & ~TX_CACHE_COOK;
    return;
  }

  htx = htxbuf(&res->buf);
  /* Check "pragma" header for HTTP/1.0 compatibility. */
  if (http_find_header(htx, ist("pragma"), &ctx, 1)) {
    if (isteqi(ctx.value, ist("no-cache"))) {
      txn->flags &= ~TX_CACHEABLE & ~TX_CACHE_COOK;
      return;
    }
  }

  /* Look for "cache-control" header and iterate over all the values
   * until we find one that specifies that caching is possible or not. */
  ctx.blk = NULL;
  while (http_find_header(htx, ist("cache-control"), &ctx, 0)) {
    if (isteqi(ctx.value, ist("public"))) {
      txn->flags |= TX_CACHEABLE | TX_CACHE_COOK;
      continue;
    }
    /* This max-age might be overridden by a s-maxage directive, do
     * not unset the TX_CACHEABLE yet. */
    if (isteqi(ctx.value, ist("max-age=0"))) {
      has_null_maxage = 1;
      continue;
    }

    /* We might have a no-cache="set-cookie" form. */
    if (isteqi(ctx.value, ist("no-cache=\"set-cookie\""))) {
      txn->flags &= ~TX_CACHE_COOK;
      continue;
    }

    if (isteqi(ctx.value, ist("private"))  || istmatchi(ctx.value, ist("private="))  ||
        isteqi(ctx.value, ist("no-cache")) || istmatchi(ctx.value, ist("no-cache=")) ||
        isteqi(ctx.value, ist("no-store")) || istmatchi(ctx.value, ist("no-store=")) ||
        isteqi(ctx.value, ist("s-maxage=0"))) {
      txn->flags &= ~TX_CACHEABLE & ~TX_CACHE_COOK;
      continue;
    }
    if (istmatchi(ctx.value, ist("s-maxage"))) {
      has_freshness_info = 1;
      has_null_maxage = 0;  /* The null max-age is overridden, ignore it */
      continue;
    }
    if (istmatchi(ctx.value, ist("max-age"))) {
      has_freshness_info = 1;
      continue;
    }
  }

  /* We had a 'max-age=0' directive but no extra s-maxage, do not cache
   * the response. */
  if (has_null_maxage) {
    txn->flags &= ~TX_CACHEABLE & ~TX_CACHE_COOK;
  }

  /* If no freshness information could be found in Cache-Control values,
   * look for an Expires header. */
  if (!has_freshness_info) {
    ctx.blk = NULL;
    has_freshness_info = http_find_header(htx, ist("expires"), &ctx, 0);
  }

  /* If no freshness information could be found in Cache-Control or Expires
   * values, look for an explicit validator. */
  if (!has_freshness_info) {
    ctx.blk = NULL;
    has_validator = 1;
    if (!http_find_header(htx, ist("etag"), &ctx, 0)) {
      ctx.blk = NULL;
      if (!http_find_header(htx, ist("last-modified"), &ctx, 0))
        has_validator = 0;
    }
  }

  /* We won't store an entry that has neither a cache validator nor an
   * explicit expiration time, as suggested in RFC 7234#3. */
  if (!has_freshness_info && !has_validator)
    txn->flags &= ~TX_CACHEABLE;
}

/*
 * In a GET, HEAD or POST request, check if the requested URI matches the stats uri
 * for the current proxy.
 *
 * It is assumed that the request is either a HEAD, GET, or POST and that the
 * uri_auth field is valid.
 *
 * Returns 1 if stats should be provided, otherwise 0.
 */
static int http_stats_check_uri(struct stream *s, struct http_txn *txn, struct proxy *px)
{
  struct uri_auth *uri_auth = px->uri_auth;
  struct htx *htx;
  struct htx_sl *sl;
  struct ist uri;

  if (!uri_auth)
    return 0;

  if (txn->meth != HTTP_METH_GET && txn->meth != HTTP_METH_HEAD && txn->meth != HTTP_METH_POST)
    return 0;

  htx = htxbuf(&s->req.buf);
  sl = http_get_stline(htx);
  uri = htx_sl_req_uri(sl);
  if (*uri_auth->uri_prefix == '/') {
    struct http_uri_parser parser = http_uri_parser_init(uri);
    uri = http_parse_path(&parser);
  }

  /* check URI size */
  if (uri_auth->uri_len > uri.len)
    return 0;

  if (memcmp(uri.ptr, uri_auth->uri_prefix, uri_auth->uri_len) != 0)
    return 0;

  return 1;
}

/* This function prepares an applet to handle the stats. It can deal with the
 * "100-continue" expectation, check that admin rules are met for POST requests,
 * and program a response message if something was unexpected. It cannot fail
 * and always relies on the stats applet to complete the job. It does not touch
 * analysers nor counters, which are left to the caller. It does not touch
 * s->target which is supposed to already point to the stats applet. The caller
 * is expected to have already assigned an appctx to the stream.
 */
static int http_handle_stats(struct stream *s, struct channel *req, struct proxy *px)
{
  struct stats_admin_rule *stats_admin_rule;
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct http_msg *msg = &txn->req;
  struct uri_auth *uri_auth = px->uri_auth;
  const char *h, *lookup, *end;
  struct appctx *appctx = __sc_appctx(s->scb);
  struct show_stat_ctx *ctx = applet_reserve_svcctx(appctx, sizeof(*ctx));
  struct htx *htx;
  struct htx_sl *sl;

  appctx->st1 = 0;
  ctx->state = STAT_STATE_INIT;
  ctx->st_code = STAT_STATUS_INIT;
  ctx->http_px = px;
  ctx->flags |= uri_auth->flags;
  ctx->flags |= STAT_F_FMT_HTML; /* assume HTML mode by default */
  if ((msg->flags & HTTP_MSGF_VER_11) && (txn->meth != HTTP_METH_HEAD))
    ctx->flags |= STAT_F_CHUNKED;

  watcher_init(&ctx->px_watch,  &ctx->obj1, offsetof(struct proxy, watcher_list));
  watcher_init(&ctx->srv_watch, &ctx->obj2, offsetof(struct server, watcher_list));

  htx = htxbuf(&req->buf);
  sl = http_get_stline(htx);
  lookup = HTX_SL_REQ_UPTR(sl) + uri_auth->uri_len;
  end = HTX_SL_REQ_UPTR(sl) + HTX_SL_REQ_ULEN(sl);

  for (h = lookup; h <= end - 3; h++) {
    if (memcmp(h, ";up", 3) == 0) {
      ctx->flags |= STAT_F_HIDE_DOWN;
      break;
    }
  }

  for (h = lookup; h <= end - 9; h++) {
    if (memcmp(h, ";no-maint", 9) == 0) {
      ctx->flags |= STAT_F_HIDE_MAINT;
      break;
    }
  }

  if (uri_auth->refresh) {
    for (h = lookup; h <= end - 10; h++) {
      if (memcmp(h, ";norefresh", 10) == 0) {
        ctx->flags |= STAT_F_NO_REFRESH;
        break;
      }
    }
  }

  for (h = lookup; h <= end - 4; h++) {
    if (memcmp(h, ";csv", 4) == 0) {
      ctx->flags &= ~(STAT_F_FMT_MASK|STAT_F_JSON_SCHM);
      break;
    }
  }

  for (h = lookup; h <= end - 6; h++) {
    if (memcmp(h, ";typed", 6) == 0) {
      ctx->flags &= ~(STAT_F_FMT_MASK|STAT_F_JSON_SCHM);
      ctx->flags |= STAT_F_FMT_TYPED;
      break;
    }
  }

  for (h = lookup; h <= end - 5; h++) {
    if (memcmp(h, ";json", 5) == 0) {
      ctx->flags &= ~(STAT_F_FMT_MASK|STAT_F_JSON_SCHM);
      ctx->flags |= STAT_F_FMT_JSON;
      break;
    }
  }

  for (h = lookup; h <= end - 12; h++) {
    if (memcmp(h, ";json-schema", 12) == 0) {
      ctx->flags &= ~STAT_F_FMT_MASK;
      ctx->flags |= STAT_F_JSON_SCHM;
      break;
    }
  }

  for (h = lookup; h <= end - 8; h++) {
    if (memcmp(h, ";st=", 4) == 0) {
      int i;
      h += 4;
      ctx->st_code = STAT_STATUS_UNKN;
      for (i = STAT_STATUS_INIT + 1; i < STAT_STATUS_SIZE; i++) {
        if (strncmp(stat_status_codes[i], h, 4) == 0) {
          ctx->st_code = i;
          break;
        }
      }
      break;
    }
  }

  ctx->scope_str = 0;
  ctx->scope_len = 0;
  for (h = lookup; h <= end - 8; h++) {
    if (memcmp(h, STAT_SCOPE_INPUT_NAME "=", strlen(STAT_SCOPE_INPUT_NAME) + 1) == 0) {
      int itx = 0;
      const char *h2;
      char scope_txt[STAT_SCOPE_TXT_MAXLEN + 1];
      const char *err;

      h += strlen(STAT_SCOPE_INPUT_NAME) + 1;
      h2 = h;
      ctx->scope_str = h2 - HTX_SL_REQ_UPTR(sl);
      while (h < end) {
        if (*h == ';' || *h == '&' || *h == ' ')
          break;
        itx++;
        h++;
      }

      if (itx > STAT_SCOPE_TXT_MAXLEN)
        itx = STAT_SCOPE_TXT_MAXLEN;
      ctx->scope_len = itx;

      /* scope_txt = search query, ctx->scope_len is always <= STAT_SCOPE_TXT_MAXLEN */
      memcpy(scope_txt, h2, itx);
      scope_txt[itx] = '\0';
      err = invalid_char(scope_txt);
      if (err) {
        /* bad char in search text => clear scope */
        ctx->scope_str = 0;
        ctx->scope_len = 0;
      }
      break;
    }
  }

  /* now check whether we have some admin rules for this request */
  list_for_each_entry(stats_admin_rule, &uri_auth->admin_rules, list) {
    if (!acl_match_cond(stats_admin_rule->cond, s->be, sess, s, SMP_OPT_DIR_REQ|SMP_OPT_FINAL))
      continue;

    /* no rule, or the rule matches */
    ctx->flags |= STAT_F_ADMIN;
    break;
  }

  if (txn->meth == HTTP_METH_GET || txn->meth == HTTP_METH_HEAD)
    appctx->st0 = STAT_HTTP_HEAD;
  else if (txn->meth == HTTP_METH_POST) {
    if (ctx->flags & STAT_F_ADMIN) {
      appctx->st0 = STAT_HTTP_POST;
      if (msg->msg_state < HTTP_MSG_DATA)
        req->analysers |= AN_REQ_HTTP_BODY;
    }
    else {
      /* POST without admin level */
      ctx->flags &= ~STAT_F_CHUNKED;
      ctx->st_code = STAT_STATUS_DENY;
      appctx->st0 = STAT_HTTP_LAST;
    }
  }
  else {
    /* Unsupported method */
    ctx->flags &= ~STAT_F_CHUNKED;
    ctx->st_code = STAT_STATUS_IVAL;
    appctx->st0 = STAT_HTTP_LAST;
  }

  s->task->nice = -32; /* small boost for HTTP statistics */
  return 1;
}

/* This function waits for the message payload at most <time> milliseconds (may
 * be set to TICK_ETERNITY). It stops to wait if at least <bytes> bytes of the
 * payload are received (0 means no limit). It returns HTTP_RULE_* depending on
 * the result:
 *
 *   - HTTP_RULE_RES_CONT when  conditions are met to stop waiting
 *   - HTTP_RULE_RES_YIELD to wait for more data
 *   - HTTP_RULE_RES_ABRT when a timeout occurred.
 *   - HTTP_RULE_RES_BADREQ if a parsing error is raised by lower level
 *   - HTTP_RULE_RES_ERROR if an internal error occurred
 *
 * If a timeout occurred, this function is responsible to emit the right response
 * to the client, depending on the channel (408 on request side, 504 on response
 * side). All other errors must be handled by the caller.
 */
enum rule_result http_wait_for_msg_body(struct stream *s, struct channel *chn,
          unsigned int time, unsigned int bytes, unsigned int large_buffer)
{
  struct session *sess = s->sess;
  struct http_txn *txn = s->txn.http;
  struct http_msg *msg = ((chn->flags & CF_ISRESP) ? &txn->rsp : &txn->req);
  struct htx *htx;
  enum rule_result ret = HTTP_RULE_RES_CONT;

  htx = htxbuf(&chn->buf);

  if (htx->flags & HTX_FL_PARSING_ERROR) {
    ret = HTTP_RULE_RES_BADREQ;
    goto end;
  }
  if (htx->flags & HTX_FL_PROCESSING_ERROR) {
    ret = HTTP_RULE_RES_ERROR;
    goto end;
  }

  /* Do nothing for bodyless and CONNECT requests */
  if (txn->meth == HTTP_METH_CONNECT || (msg->flags & HTTP_MSGF_BODYLESS))
    goto end;

  if (!(chn->flags & CF_ISRESP)) {
    if (http_handle_expect_hdr(s, htx, msg) == -1) {
      ret = HTTP_RULE_RES_ERROR;
      goto end;
    }
  }

  /* Now we're are waiting for the payload. We just need to know if all
   * data have been received or if the buffer is full.
   */
  if ((htx->flags & HTX_FL_EOM) || htx_get_tail_type(htx) > HTX_BLK_DATA)
    goto end; /* all data received */

  if (bytes) {
    struct htx_blk *blk;
    unsigned int len = 0;

    for (blk = htx_get_first_blk(htx); blk; blk = htx_get_next_blk(htx, blk)) {
      if (htx_get_blk_type(blk) != HTX_BLK_DATA)
        continue;
      len += htx_get_blksz(blk);
      if (len >= bytes)
        goto end;
    }
  }

  if (channel_htx_full(chn, htx, global.tune.maxrewrite) || sc_waiting_room(chn_prod(chn))) {
    struct buffer lbuf = BUF_NULL;

    if (large_buffer == 0 || b_is_large(&chn->buf) || !htx_move_to_large_buffer(&lbuf, &chn->buf))
      goto end; /* don't use large buffer or already a large buffer */
    b_free(&chn->buf);
    offer_buffers(s, 1);
    chn->buf = lbuf;
    htx = htxbuf(&chn->buf);
  }

  if ((chn->flags & CF_READ_TIMEOUT) || tick_is_expired(chn->analyse_exp, now_ms)) {
    if (!(chn->flags & CF_ISRESP))
      goto abort_req;
    goto abort_res;
  }

  /* we get here if we need to wait for more data */

  if ((s->scf->flags & SC_FL_ERROR) ||
      ((s->scf->flags & SC_FL_EOS) && proxy_abrt_close_def(s->be, 1)))
    ret = HTTP_RULE_RES_CONT;
  else if (!(chn_prod(chn)->flags & (SC_FL_ERROR|SC_FL_EOS|SC_FL_ABRT_DONE))) {
    if (!tick_isset(chn->analyse_exp))
      chn->analyse_exp = tick_add_ifset(now_ms, time);
    ret = HTTP_RULE_RES_YIELD;
  }

  end:
  if (ret != HTTP_RULE_RES_YIELD)
    chn->analyse_exp = TICK_ETERNITY;

  if (htx->flags & (HTX_FL_FRAGMENTED|HTX_FL_UNORDERED))
    htx_defrag(htx, NULL, 0);
  return ret;

  abort:
  http_set_term_flags(s);
  http_reply_and_close(s, txn->status, http_error_message(s));
  ret = HTTP_RULE_RES_ABRT;
  goto end;

  abort_req:
  txn->status = 408;
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_CLITO;
  if (sess->fe_tgcounters)
    _HA_ATOMIC_INC(&sess->fe_tgcounters->failed_req);
  if (sess->li_tgcounters)
    _HA_ATOMIC_INC(&sess->li_tgcounters->failed_req);
  goto abort;

  abort_res:
  txn->status = 504;
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_SRVTO;
  stream_inc_http_fail_ctr(s);
  goto abort;
}

void http_perform_server_redirect(struct stream *s, struct stconn *sc)
{
  struct channel *req = &s->req;
  struct channel *res = &s->res;
  struct server *srv;
  struct htx *htx;
  struct htx_sl *sl;
  struct ist path, location;
  unsigned int flags;
  struct http_uri_parser parser;

  /*
   * Create the location
   */
  chunk_reset(&trash);

  /* 1: add the server's prefix */
  /* special prefix "/" means don't change URL */
  srv = __objt_server(s->target);
  if (srv->rdr_len != 1 || *srv->rdr_pfx != '/') {
    if (!chunk_memcat(&trash, srv->rdr_pfx, srv->rdr_len))
      return;
  }

  /* 2: add the request Path */
  htx = htxbuf(&req->buf);
  sl = http_get_stline(htx);
  parser = http_uri_parser_init(htx_sl_req_uri(sl));
  path = http_parse_path(&parser);
  if (!isttest(path))
    return;

  if (!chunk_memcat(&trash, path.ptr, path.len))
    return;
  location = ist2(trash.area, trash.data);

  /*
   * Create the 302 response
   */
  htx = htx_from_buf(&res->buf);
  flags = (HTX_SL_F_IS_RESP|HTX_SL_F_VER_11|HTX_SL_F_XFER_LEN|HTX_SL_F_CLEN|HTX_SL_F_BODYLESS);
  sl = htx_add_stline(htx, HTX_BLK_RES_SL, flags,
          ist("HTTP/1.1"), ist("302"), ist("Found"));
  if (!sl)
    goto fail;
  sl->info.res.status = 302;
  s->txn.http->status = 302;

        if (!htx_add_header(htx, ist("Cache-Control"), ist("no-cache")) ||
      !htx_add_header(htx, ist("Content-length"), ist("0")) ||
      !htx_add_header(htx, ist("Location"), location))
    goto fail;

  if (!htx_add_endof(htx, HTX_BLK_EOH))
    goto fail;

  htx->flags |= HTX_FL_EOM;
  htx_to_buf(htx, &res->buf);

  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_LOCAL;
  if (!(s->flags & SF_FINST_MASK))
    s->flags |= SF_FINST_C;

  if (!http_forward_proxy_resp(s, 1))
    goto fail;

  /* return without error. */
  sc_abort(sc);
  sc_shutdown(sc);
  s->conn_err_type = STRM_ET_NONE;
  sc->state = SC_ST_CLO;


  /* FIXME: we should increase a counter of redirects per server and per backend. */
  srv_inc_sess_ctr(srv);
  srv_set_sess_last(srv);
  return;

  fail:
  /* If an error occurred, remove the incomplete HTTP response from the
   * buffer */
  channel_htx_truncate(res, htx);
}

/* This function terminates the request because it was completely analyzed or
 * because an error was triggered during the body forwarding.
 */
static void http_end_request(struct stream *s)
{
  struct channel *chn = &s->req;
  struct http_txn *txn = s->txn.http;

  DBG_TRACE_ENTER(STRM_EV_HTTP_ANA, s, txn);

  if (unlikely(txn->req.msg_state < HTTP_MSG_DONE)) {
    DBG_TRACE_DEVEL("waiting end of the request", STRM_EV_HTTP_ANA, s, txn);
    return;
  }

  if (txn->req.msg_state == HTTP_MSG_DONE) {
    /* No need to read anymore, the request was completely parsed.
     * We can shut the read side unless we want to abort_on_close,
     * or we have a POST request. The issue with POST requests is
     * that some browsers still send a CRLF after the request, and
     * this CRLF must be read so that it does not remain in the kernel
     * buffers, otherwise a close could cause an RST on some systems
     * (eg: Linux).
     */
    if (!proxy_abrt_close_def(s->be, 1) && txn->meth != HTTP_METH_POST)
      channel_dont_read(chn);

    /* if the server closes the connection, we want to immediately react
     * and close the socket to save packets and syscalls.
     */
    s->scb->flags |= SC_FL_NOHALF;

    /* In any case we've finished parsing the request so we must
     * disable Nagle when sending data because 1) we're not going
     * to shut this side, and 2) the server is waiting for us to
     * send pending data.
     */
    s->scb->flags |= SC_FL_SND_NEVERWAIT;

    if (txn->rsp.msg_state < HTTP_MSG_BODY ||
        (txn->rsp.msg_state < HTTP_MSG_DONE && s->scb->state != SC_ST_CLO)) {
      /* The server has not finished to respond and the
       * backend SC is not closed, so we don't want to move in
       * order not to upset it.
       */
      DBG_TRACE_DEVEL("waiting end of the response", STRM_EV_HTTP_ANA, s, txn);
      return;
    }

    /* When we get here, it means that both the request and the
     * response have finished receiving. Depending on the connection
     * mode, we'll have to wait for the last bytes to leave in either
     * direction, and sometimes for a close to be effective.
     */
    if (txn->flags & TX_CON_WANT_TUN) {
      /* Tunnel mode will not have any analyser so it needs to
       * poll for reads.
       */
      channel_auto_read(&s->req);
      txn->req.msg_state = HTTP_MSG_TUNNEL;
      s->scb->flags &= ~SC_FL_NOHALF;
      if (txn->rsp.msg_state != HTTP_MSG_TUNNEL)
        s->res.flags |= CF_WAKE_ONCE;
    }
    else {
      /* we're not expecting any new data to come for this
       * transaction, so we can close it.
       *
       *  However, there is an exception if the response
       *  length is undefined. In this case, we need to wait
       *  the close from the server. The response will be
       *  switched in TUNNEL mode until the end.
       */
      if (!(txn->rsp.flags & HTTP_MSGF_XFER_LEN) &&
          txn->rsp.msg_state != HTTP_MSG_CLOSED)
        goto check_channel_flags;

      if (!(s->scb->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED))) {
        sc_schedule_abort(s->scf);
        sc_schedule_shutdown(s->scb);
      }
    }
    goto check_channel_flags;
  }

  if (txn->req.msg_state == HTTP_MSG_CLOSING) {
    http_msg_closing:
    /* nothing else to forward, just waiting for the output buffer
     * to be empty and for the shut_wanted to take effect.
     */
    if (!co_data(chn)) {
      txn->req.msg_state = HTTP_MSG_CLOSED;
      goto http_msg_closed;
    }
    DBG_TRACE_LEAVE(STRM_EV_HTTP_ANA, s, txn);
    return;
  }

  if (txn->req.msg_state == HTTP_MSG_CLOSED) {
    http_msg_closed:
    /* if we don't know whether the server will close, we need to hard close */
    if (txn->rsp.flags & HTTP_MSGF_XFER_LEN)
      s->scb->flags |= SC_FL_NOLINGER;  /* we want to close ASAP */
    /* see above in MSG_DONE why we only do this in these states */
    if (!proxy_abrt_close_def(s->be, 1))
      channel_dont_read(chn);
    goto end;
  }

  check_channel_flags:
  /* Here, we are in HTTP_MSG_DONE or HTTP_MSG_TUNNEL */
  if (s->scb->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED)) {
    /* if we've just closed an output, let's switch */
    txn->req.msg_state = HTTP_MSG_CLOSING;
    goto http_msg_closing;
  }

  end:
  chn->analysers &= AN_REQ_FLT_END;
  if (txn->req.msg_state == HTTP_MSG_TUNNEL) {
    s->scb->flags |= SC_FL_SND_NEVERWAIT;
    if (HAS_REQ_DATA_FILTERS(s))
      chn->analysers |= AN_REQ_FLT_XFER_DATA;
    else
      c_adv(chn, htxbuf(&chn->buf)->data - co_data(chn));
  }
  channel_auto_close(chn);
  channel_auto_read(chn);
  DBG_TRACE_LEAVE(STRM_EV_HTTP_ANA, s, txn);
}


/* This function terminates the response because it was completely analyzed or
 * because an error was triggered during the body forwarding.
 */
static void http_end_response(struct stream *s)
{
  struct channel *chn = &s->res;
  struct http_txn *txn = s->txn.http;

  DBG_TRACE_ENTER(STRM_EV_HTTP_ANA, s, txn);

  if (unlikely(txn->rsp.msg_state < HTTP_MSG_DONE)) {
    DBG_TRACE_DEVEL("waiting end of the response", STRM_EV_HTTP_ANA, s, txn);
    return;
  }

  if (txn->rsp.msg_state == HTTP_MSG_DONE) {
    /* In theory, we don't need to read anymore, but we must
     * still monitor the server connection for a possible close
     * while the request is being uploaded, so we don't disable
     * reading.
     */
    /* channel_dont_read(chn); */

    if (txn->req.msg_state < HTTP_MSG_DONE && s->scf->state != SC_ST_CLO) {
      /* The client seems to still be sending data, probably
       * because we got an error response during an upload.
       * We have the choice of either breaking the connection
       * or letting it pass through. Let's do the later.
       */
      DBG_TRACE_DEVEL("waiting end of the request", STRM_EV_HTTP_ANA, s, txn);
      return;
    }

    /* When we get here, it means that both the request and the
     * response have finished receiving. Depending on the connection
     * mode, we'll have to wait for the last bytes to leave in either
     * direction, and sometimes for a close to be effective.
     */
    if (txn->flags & TX_CON_WANT_TUN) {
      channel_auto_read(&s->res);
      txn->rsp.msg_state = HTTP_MSG_TUNNEL;
      if (txn->req.msg_state != HTTP_MSG_TUNNEL)
        s->req.flags |= CF_WAKE_ONCE;
    }
    else {
      /* we're not expecting any new data to come for this
       * transaction, so we can close it.
       */
      if (!(s->scf->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED))) {
        sc_schedule_abort(s->scb);
        sc_schedule_shutdown(s->scf);
      }
    }
    goto check_channel_flags;
  }

  if (txn->rsp.msg_state == HTTP_MSG_CLOSING) {
    http_msg_closing:
    /* nothing else to forward, just waiting for the output buffer
     * to be empty and for the shut_wanted to take effect.
     */
    if (!co_data(chn)) {
      txn->rsp.msg_state = HTTP_MSG_CLOSED;
      goto http_msg_closed;
    }
    DBG_TRACE_LEAVE(STRM_EV_HTTP_ANA, s, txn);
    return;
  }

  if (txn->rsp.msg_state == HTTP_MSG_CLOSED) {
    http_msg_closed:
    /* drop any pending data */
    channel_htx_truncate(&s->req, htxbuf(&s->req.buf));
    channel_abort(&s->req);
    goto end;
  }

  check_channel_flags:
  /* Here, we are in HTTP_MSG_DONE or HTTP_MSG_TUNNEL */
  if (s->scf->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED)) {
    /* if we've just closed an output, let's switch */
    txn->rsp.msg_state = HTTP_MSG_CLOSING;
    goto http_msg_closing;
  }

  end:
  chn->analysers &= AN_RES_FLT_END;
  if (txn->rsp.msg_state == HTTP_MSG_TUNNEL) {
    s->scf->flags |= SC_FL_SND_NEVERWAIT;
    if (HAS_RSP_DATA_FILTERS(s))
      chn->analysers |= AN_RES_FLT_XFER_DATA;
    else
      c_adv(chn, htxbuf(&chn->buf)->data - co_data(chn));
  }
  channel_auto_close(chn);
  channel_auto_read(chn);
  DBG_TRACE_LEAVE(STRM_EV_HTTP_ANA, s, txn);
}

/* Forward a response generated by HAProxy (error/redirect/return). This
 * function forwards all pending incoming data. If <final> is set to 0, nothing
 * more is performed. It is used for 1xx informational messages. Otherwise, the
 * transaction is terminated and the request is emptied. On success 1 is
 * returned. If an error occurred, 0 is returned. If it fails, this function
 * only exits. It is the caller responsibility to do the cleanup.
 */
int http_forward_proxy_resp(struct stream *s, int final)
{
  struct channel *req = &s->req;
  struct channel *res = &s->res;
  struct htx *htx = htxbuf(&res->buf);
  size_t data;

  if (final) {
    if (s->txn.http->server_status == -1)
      s->txn.http->server_status = 0;

    if (!htx_is_empty(htx) && !http_eval_after_res_rules(s))
      return 0;

    if (s->txn.http->meth == HTTP_METH_HEAD)
      htx_skip_msg_payload(htx);

    /* Response from haproxy, override HTTP response version using the request one */
    s->txn.http->rsp.vsn = s->txn.http->req.vsn;

    channel_auto_read(req);
    channel_abort(req);
    channel_htx_erase(req, htxbuf(&req->buf));

    channel_auto_read(res);
    channel_auto_close(res);
    sc_schedule_abort(s->scb);
    s->scb->flags |= SC_FL_EOI; /* The response is terminated, add EOI */
    htxbuf(&res->buf)->flags |= HTX_FL_EOM; /* no more data are expected */
  }
  else {
    /* Send ASAP informational messages. Rely on SC_FL_EOI for final
     * response.
     */
    s->scf->flags |= SC_FL_SND_ASAP;
  }

  data = htx->data - co_data(res);
  c_adv(res, data);
  htx->first = -1;
  s->scf->bytes_out += data;
  return 1;
}

void http_server_error(struct stream *s, struct stconn *sc, int err,
           int finst, struct http_reply *msg)
{
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= err;
  if (!(s->flags & SF_FINST_MASK))
    s->flags |= finst;

  http_reply_and_close(s, s->txn.http->status, msg);
}

void http_reply_and_close(struct stream *s, short status, struct http_reply *msg)
{
  if (!msg) {
    channel_htx_truncate(&s->res, htxbuf(&s->res.buf));
    goto end;
  }

  if (http_reply_message(s, msg) == -1) {
    /* On error, return a 500 error message, but don't rewrite it if
     * it is already an internal error. If it was already a "const"
     * 500 error, just fail.
     */
    if (s->txn.http->status == 500) {
      if (s->txn.http->flags & TX_CONST_REPLY)
        goto end;
      s->txn.http->flags |= TX_CONST_REPLY;
    }
    s->txn.http->status = 500;
    s->txn.http->http_reply = NULL;
    return http_reply_and_close(s, s->txn.http->status,
              http_error_message(s));
  }

end:
  /* At this staged, HTTP analysis is finished */
  s->req.analysers &= AN_REQ_FLT_END;
  s->req.analyse_exp = TICK_ETERNITY;

  s->res.analysers &= AN_RES_FLT_END;
  s->res.analyse_exp = TICK_ETERNITY;

  channel_auto_read(&s->req);
  channel_abort(&s->req);
  channel_htx_erase(&s->req, htxbuf(&s->req.buf));
  channel_auto_read(&s->res);
  channel_auto_close(&s->res);
  sc_schedule_abort(s->scb);
}

struct http_reply *http_error_message(struct stream *s)
{
  const int msgnum = http_get_status_idx(s->txn.http->status);

  if (s->txn.http->http_reply)
    return s->txn.http->http_reply;
  else if (s->be->replies[msgnum])
    return s->be->replies[msgnum];
  else if (strm_fe(s)->replies[msgnum])
    return strm_fe(s)->replies[msgnum];
  else
    return &http_err_replies[msgnum];
}

/* Produces an HTX message from an http reply. Depending on the http reply type,
 * an errorfile, a raw file or a log-format string is used. On success, it
 * returns 0. If an error occurs -1 is returned. If it fails, this function only
 * exits. It is the caller responsibility to do the cleanup.
 */
int http_reply_to_htx(struct stream *s, struct htx *htx, struct http_reply *reply)
{
  struct buffer *errmsg;
  struct htx_sl *sl;
  struct buffer *body = NULL;
  const char *status, *reason, *clen, *ctype;
  unsigned int slflags;
  int ret = 0;

  /*
   * - HTTP_REPLY_ERRFILES unexpected here. handled as no payload if so
   *
   * - HTTP_REPLY_INDIRECT: switch on another reply if defined or handled
   *   as no payload if NULL. the TXN status code is set with the status
   *   of the original reply.
   */

  if (reply->type == HTTP_REPLY_INDIRECT) {
    if (reply->body.reply)
      reply = reply->body.reply;
  }
  if (reply->type == HTTP_REPLY_ERRMSG && !reply->body.errmsg)  {
    /* get default error message */
    if (reply == s->txn.http->http_reply)
      s->txn.http->http_reply = NULL;
    reply = http_error_message(s);
    if (reply->type == HTTP_REPLY_INDIRECT) {
      if (reply->body.reply)
        reply = reply->body.reply;
    }
  }

  if (reply->type == HTTP_REPLY_ERRMSG) {
    /* implicit or explicit error message*/
    errmsg = reply->body.errmsg;
    if (errmsg && !b_is_null(errmsg)) {
      if (!htx_copy_msg(htx, errmsg))
        goto fail;
    }
  }
  else {
    /* no payload, file or log-format string */
    if (reply->type == HTTP_REPLY_RAW) {
      /* file */
      body = &reply->body.obj;
    }
    else if (reply->type == HTTP_REPLY_LOGFMT) {
      /* log-format string */
      body = alloc_trash_chunk();
      if (!body)
        goto fail_alloc;
      body->data = build_logline(s, body->area, body->size, &reply->body.fmt);
    }
    /* else no payload */

    status = ultoa(reply->status);
    reason = http_get_reason(reply->status);
    slflags = (HTX_SL_F_IS_RESP|HTX_SL_F_VER_11|HTX_SL_F_XFER_LEN|HTX_SL_F_CLEN);
    if (!body || !b_data(body))
      slflags |= HTX_SL_F_BODYLESS;
    sl = htx_add_stline(htx, HTX_BLK_RES_SL, slflags, ist("HTTP/1.1"), ist(status), ist(reason));
    if (!sl)
      goto fail;
    sl->info.res.status = reply->status;

    clen = (body ? ultoa(b_data(body)) : "0");
    ctype = reply->ctype;

    if (!LIST_ISEMPTY(&reply->hdrs)) {
      struct http_reply_hdr *hdr;
      struct buffer *value = alloc_trash_chunk();

      if (!value)
        goto fail;

      list_for_each_entry(hdr, &reply->hdrs, list) {
        chunk_reset(value);
        value->data = build_logline(s, value->area, value->size, &hdr->value);
        if (b_data(value) && !htx_add_header(htx, hdr->name, ist2(b_head(value), b_data(value)))) {
          free_trash_chunk(value);
          goto fail;
        }
        chunk_reset(value);
      }
      free_trash_chunk(value);
    }

    if (!htx_add_header(htx, ist("content-length"), ist(clen)) ||
        (body && b_data(body) && ctype && !htx_add_header(htx, ist("content-type"), ist(ctype))) ||
        !htx_add_endof(htx, HTX_BLK_EOH) ||
        (body && b_data(body) && !htx_add_data_atonce(htx, ist2(b_head(body), b_data(body)))))
      goto fail;

    htx->flags |= HTX_FL_EOM;
  }

  leave:
  if (reply->type == HTTP_REPLY_LOGFMT)
    free_trash_chunk(body);
  return ret;

  fail_alloc:
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_RESOURCE;
  /* fall through */
  fail:
  ret = -1;
  goto leave;
}

/* Send an http reply to the client. On success, it returns 0. If an error
 * occurs -1 is returned and the response channel is truncated, removing this
 * way the faulty reply. This function may fail when the reply is formatted
 * (http_reply_to_htx) or when the reply is forwarded
 * (http_forward_proxy_resp). On the last case, it is because a
 * http-after-response rule fails.
 */
int http_reply_message(struct stream *s, struct http_reply *reply)
{
  struct channel *res = &s->res;
  struct htx *htx = htx_from_buf(&res->buf);

  if (s->txn.http->status == -1)
    s->txn.http->status = reply->status;
  channel_htx_truncate(res, htx);

  if (http_reply_to_htx(s, htx, reply) == -1)
    goto fail;

  htx_to_buf(htx, &s->res.buf);
  if (!http_forward_proxy_resp(s, 1))
    goto fail;
  return 0;

  fail:
  channel_htx_truncate(res, htx);
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_PRXCOND;
  return -1;
}

/* Return the error message corresponding to s->conn_err_type. It is assumed
 * that the server side is closed. Note that err_type is actually a
 * bitmask, where almost only aborts may be cumulated with other
 * values. We consider that aborted operations are more important
 * than timeouts or errors due to the fact that nobody else in the
 * logs might explain incomplete retries. All others should avoid
 * being cumulated. It should normally not be possible to have multiple
 * aborts at once, but just in case, the first one in sequence is reported.
 * Note that connection errors appearing on the second request of a keep-alive
 * connection are not reported since this allows the client to retry.
 */
void http_return_srv_error(struct stream *s, struct stconn *sc)
{
  int err_type = s->conn_err_type;

  /* set s->txn.http->status for http_error_message(s) */
  if (err_type & STRM_ET_QUEUE_ABRT) {
    s->txn.http->status = -1;
    http_server_error(s, sc, SF_ERR_CLICL, SF_FINST_Q, NULL);
  }
  else if (err_type & STRM_ET_CONN_ABRT) {
    s->txn.http->status = -1;
    http_server_error(s, sc, SF_ERR_CLICL, SF_FINST_C, NULL);
  }
  else if (err_type & STRM_ET_QUEUE_TO) {
    s->txn.http->status = 503;
    http_server_error(s, sc, SF_ERR_SRVTO, SF_FINST_Q,
          http_error_message(s));
  }
  else if (err_type & STRM_ET_QUEUE_ERR) {
    s->txn.http->status = 503;
    http_server_error(s, sc, SF_ERR_SRVCL, SF_FINST_Q,
          http_error_message(s));
  }
  else if (err_type & STRM_ET_CONN_TO) {
    s->txn.http->status = 503;
    http_server_error(s, sc, SF_ERR_SRVTO, SF_FINST_C,
          (s->txn.http->flags & TX_NOT_FIRST) ? NULL :
          http_error_message(s));
  }
  else if (err_type & STRM_ET_CONN_ERR) {
    s->txn.http->status = 503;
    http_server_error(s, sc, SF_ERR_SRVCL, SF_FINST_C,
          (s->flags & SF_SRV_REUSED) ? NULL :
          http_error_message(s));
  }
  else if (err_type & STRM_ET_CONN_RES) {
    s->txn.http->status = 503;
    http_server_error(s, sc, SF_ERR_RESOURCE, SF_FINST_C,
          (s->txn.http->flags & TX_NOT_FIRST) ? NULL :
          http_error_message(s));
  }
  else { /* STRM_ET_CONN_OTHER and others */
    s->txn.http->status = 500;
    http_server_error(s, sc, SF_ERR_INTERNAL, SF_FINST_C,
          http_error_message(s));
  }
}


/* Handle Expect: 100-continue for HTTP/1.1 messages if necessary. It returns 0
 * on success and -1 on error.
 */
static int http_handle_expect_hdr(struct stream *s, struct htx *htx, struct http_msg *msg)
{
  /* If we have HTTP/1.1 message with a body and Expect: 100-continue,
   * then we must send an HTTP/1.1 100 Continue intermediate response.
   */
  if (!(msg->flags & HTTP_MSGF_EXPECT_CHECKED) &&
      (msg->flags & HTTP_MSGF_VER_11) &&
      (msg->flags & (HTTP_MSGF_CNT_LEN|HTTP_MSGF_TE_CHNK))) {
    struct ist hdr = { .ptr = "Expect", .len = 6 };
    struct http_hdr_ctx ctx;

    ctx.blk = NULL;
    /* Expect is allowed in 1.1, look for it */
    if (http_find_header(htx, hdr, &ctx, 0) &&
        unlikely(isteqi(ctx.value, ist2("100-continue", 12)))) {
      if (http_reply_100_continue(s) == -1)
        return -1;
      http_remove_header(htx, &ctx);
    }
  }
  msg->flags |= HTTP_MSGF_EXPECT_CHECKED;
  return 0;
}

/* Send a 100-Continue response to the client. It returns 0 on success and -1
 * on error. The response channel is updated accordingly.
 */
static int http_reply_100_continue(struct stream *s)
{
  struct channel *res = &s->res;
  struct htx *htx = htx_from_buf(&res->buf);
  struct htx_sl *sl;
  unsigned int flags = (HTX_SL_F_IS_RESP|HTX_SL_F_VER_11|
            HTX_SL_F_XFER_LEN|HTX_SL_F_BODYLESS);

  sl = htx_add_stline(htx, HTX_BLK_RES_SL, flags,
          ist("HTTP/1.1"), ist("100"), ist("Continue"));
  if (!sl)
    goto fail;
  sl->info.res.status = 100;

  if (!htx_add_endof(htx, HTX_BLK_EOH))
    goto fail;

  if (!http_forward_proxy_resp(s, 0))
    goto fail;
  return 0;

  fail:
  /* If an error occurred, remove the incomplete HTTP response from the
   * buffer */
  channel_htx_truncate(res, htx);
  return -1;
}


/*
 * Capture headers from message <htx> according to header list <cap_hdr>, and
 * fill the <cap> pointers appropriately.
 */
static void http_capture_headers(struct htx *htx, char **cap, struct cap_hdr *cap_hdr)
{
  struct cap_hdr *h;
  int32_t pos;

  for (pos = htx_get_first(htx); pos != -1; pos = htx_get_next(htx, pos)) {
    struct htx_blk *blk = htx_get_blk(htx, pos);
    enum htx_blk_type type = htx_get_blk_type(blk);
    struct ist n, v;

    if (type == HTX_BLK_EOH)
      break;
    if (type != HTX_BLK_HDR)
      continue;

    n = htx_get_blk_name(htx, blk);

    for (h = cap_hdr; h; h = h->next) {
      if (h->namelen && (h->namelen == n.len) &&
          (strncasecmp(n.ptr, h->name, h->namelen) == 0)) {
        if (cap[h->index] == NULL)
          cap[h->index] =
            pool_alloc(h->pool);

        if (cap[h->index] == NULL) {
          ha_alert("HTTP capture : out of memory.\n");
          break;
        }

        v = htx_get_blk_value(htx, blk);
        v = isttrim(v, h->len);

        memcpy(cap[h->index], v.ptr, v.len);
        cap[h->index][v.len]=0;
      }
    }
  }
}

/* Delete a value in a header between delimiters <from> and <next>. The header
 * itself is delimited by <start> and <end> pointers. The number of characters
 * displaced is returned, and the pointer to the first delimiter is updated if
 * required. The function tries as much as possible to respect the following
 * principles :
 * - replace <from> delimiter by the <next> one unless <from> points to <start>,
 *   in which case <next> is simply removed
 * - set exactly one space character after the new first delimiter, unless there
 *   are not enough characters in the block being moved to do so.
 * - remove unneeded spaces before the previous delimiter and after the new
 *   one.
 *
 * It is the caller's responsibility to ensure that :
 *   - <from> points to a valid delimiter or <start> ;
 *   - <next> points to a valid delimiter or <end> ;
 *   - there are non-space chars before <from>.
 */
static int http_del_hdr_value(char *start, char *end, char **from, char *next)
{
  char *prev = *from;

  if (prev == start) {
    /* We're removing the first value. eat the semicolon, if <next>
     * is lower than <end> */
    if (next < end)
      next++;

    while (next < end && HTTP_IS_SPHT(*next))
      next++;
  }
  else {
    /* Remove useless spaces before the old delimiter. */
    while (HTTP_IS_SPHT(*(prev-1)))
      prev--;
    *from = prev;

    /* copy the delimiter and if possible a space if we're
     * not at the end of the line.
     */
    if (next < end) {
      *prev++ = *next++;
      if (prev + 1 < next)
        *prev++ = ' ';
      while (next < end && HTTP_IS_SPHT(*next))
        next++;
    }
  }
  memmove(prev, next, end - next);
  return (prev - next);
}


/* Formats the start line of the request (without CRLF) and puts it in <str> and
 * return the written length. The line can be truncated if it exceeds <len>.
 */
static size_t http_fmt_req_line(const struct htx_sl *sl, char *str, size_t len)
{
  struct ist dst = ist2(str, 0);

  if (istcat(&dst, htx_sl_req_meth(sl), len) == -1)
    goto end;
  if (dst.len + 1 > len)
    goto end;
  dst.ptr[dst.len++] = ' ';

  if (istcat(&dst, htx_sl_req_uri(sl), len) == -1)
    goto end;
  if (dst.len + 1 > len)
    goto end;
  dst.ptr[dst.len++] = ' ';

  istcat(&dst, htx_sl_req_vsn(sl), len);
  end:
  return dst.len;
}

/*
 * Print a debug line with a start line.
 */
static void http_debug_stline(const char *dir, struct stream *s, const struct htx_sl *sl)
{
        struct session *sess = strm_sess(s);
        int max;

        chunk_printf(&trash, "%08x:%s.%s[%04x:%04x]: ", s->uniq_id, s->be->id,
                     dir,
                     objt_conn(sess->origin) ? (unsigned short)__objt_conn(sess->origin)->handle.fd : -1,
                     sc_conn(s->scb) ? (unsigned short)(__sc_conn(s->scb))->handle.fd : -1);

        max = HTX_SL_P1_LEN(sl);
        UBOUND(max, trash.size - trash.data - 3);
        chunk_memcat(&trash, HTX_SL_P1_PTR(sl), max);
        trash.area[trash.data++] = ' ';

        max = HTX_SL_P2_LEN(sl);
        UBOUND(max, trash.size - trash.data - 2);
        chunk_memcat(&trash, HTX_SL_P2_PTR(sl), max);
        trash.area[trash.data++] = ' ';

        max = HTX_SL_P3_LEN(sl);
        UBOUND(max, trash.size - trash.data - 1);
        chunk_memcat(&trash, HTX_SL_P3_PTR(sl), max);
        trash.area[trash.data++] = '\n';

        DISGUISE(write(1, trash.area, trash.data));
}

/*
 * Print a debug line with a header.
 */
static void http_debug_hdr(const char *dir, struct stream *s, const struct ist n, const struct ist v)
{
        struct session *sess = strm_sess(s);
        int max;

        chunk_printf(&trash, "%08x:%s.%s[%04x:%04x]: ", s->uniq_id, s->be->id,
                     dir,
                     objt_conn(sess->origin) ? (unsigned short)__objt_conn(sess->origin)->handle.fd : -1,
                     sc_conn(s->scb) ? (unsigned short)(__sc_conn(s->scb))->handle.fd : -1);

        max = n.len;
        UBOUND(max, trash.size - trash.data - 3);
        chunk_memcat(&trash, n.ptr, max);
        trash.area[trash.data++] = ':';
        trash.area[trash.data++] = ' ';

        max = v.len;
        UBOUND(max, trash.size - trash.data - 1);
        chunk_memcat(&trash, v.ptr, max);
        trash.area[trash.data++] = '\n';

        DISGUISE(write(1, trash.area, trash.data));
}

void http_txn_reset_req(struct http_txn *txn)
{
  txn->req.flags = 0;
  txn->req.msg_state = HTTP_MSG_RQBEFORE; /* at the very beginning of the request */
}

void http_txn_reset_res(struct http_txn *txn)
{
  txn->rsp.flags = 0;
  txn->rsp.msg_state = HTTP_MSG_RPBEFORE; /* at the very beginning of the response */
}

/*
 * Create and initialize a new HTTP transaction for stream <s>. This should be
 * used before processing any new request. It returns the transaction or NLULL
 * on error.
 */
struct http_txn *http_create_txn(struct stream *s)
{
  struct http_txn *txn;
  struct stconn *sc = s->scf;

  if ((s->flags & SF_TXN_MASK) != SF_TXN_NONE)
    return NULL;

  txn = pool_alloc(pool_head_http_txn);
  if (!txn)
    return NULL;
  s->txn.http = txn;

  txn->meth = HTTP_METH_OTHER;
  txn->flags = ((sc && sc_ep_test(sc, SE_FL_NOT_FIRST)) ? TX_NOT_FIRST : 0);
  txn->status = -1;
  txn->server_status = -1;
  txn->http_reply = NULL;
  txn->l7_buffer = BUF_NULL;
  write_u32(txn->cache_hash, 0);

  txn->cookie_first_date = 0;
  txn->cookie_last_date = 0;

  txn->srv_cookie = NULL;
  txn->cli_cookie = NULL;
  txn->uri = NULL;

  http_txn_reset_req(txn);
  http_txn_reset_res(txn);

  txn->req.chn = &s->req;
  txn->rsp.chn = &s->res;

  txn->auth.method = HTTP_AUTH_UNKNOWN;

  s->flags |= SF_TXN_HTTP;

  /* here we don't want to re-initialize s->vars_txn and s->vars_reqres
   * variable lists, because they were already initialized upon stream
   * creation in stream_new(), and thus may already contain some variables
   */

  return txn;
}

/* to be used at the end of a transaction */
void http_destroy_txn(struct stream *s)
{
  struct http_txn *txn = s->txn.http;

  /* these ones will have been dynamically allocated */
  pool_free(pool_head_requri, txn->uri);
  pool_free(pool_head_capture, txn->cli_cookie);
  pool_free(pool_head_capture, txn->srv_cookie);
  pool_free(pool_head_uniqueid, s->unique_id.ptr);

  s->unique_id = IST_NULL;
  txn->uri = NULL;
  txn->srv_cookie = NULL;
  txn->cli_cookie = NULL;

  vars_prune(&s->vars_txn, s->sess, s);
  vars_prune(&s->vars_reqres, s->sess, s);

  b_free(&txn->l7_buffer);

  pool_free(pool_head_http_txn, txn);
  s->txn.http = NULL;
  s->flags &= ~SF_TXN_MASK;
}


void http_set_term_flags(struct stream *s)
{
  if (!(s->flags & SF_ERR_MASK))
    s->flags |= SF_ERR_PRXCOND;

  if (!(s->flags & SF_FINST_MASK)) {
    if (s->scb->state == SC_ST_INI) {
      /* Before any connection attempt on the server side, we
       * are still in the request analysis. Just take case to
       * detect tarpit error
       */
      if (s->req.analysers & AN_REQ_HTTP_TARPIT)
        s->flags |= SF_FINST_T;
      else
        s->flags |= SF_FINST_R;
    }
    else if (s->scb->state == SC_ST_QUE)
      s->flags |= SF_FINST_Q;
    else if (sc_state_in(s->scb->state, SC_SB_REQ|SC_SB_TAR|SC_SB_ASS|SC_SB_CON|SC_SB_CER|SC_SB_RDY)) {
      if (unlikely(objt_applet(s->target))) {
        s->flags |= SF_FINST_R;
      }
      else
        s->flags |= SF_FINST_C;
    }
    else {
      if (s->txn.http->rsp.msg_state < HTTP_MSG_DATA) {
        /* We are still processing the response headers */
        s->flags |= SF_FINST_H;
      }
      // (res == (done|closing|closed)) & (res->flags & shutw)
      else if (s->txn.http->rsp.msg_state >= HTTP_MSG_DONE && s->txn.http->rsp.msg_state < HTTP_MSG_TUNNEL &&
         (s->flags & (SF_ERR_CLITO|SF_ERR_CLICL))) {
        /* A client error was reported and we are
         * transmitting the last block of data
         */
        s->flags |= SF_FINST_L;
      }
      else {
        /* Otherwise we are in DATA phase on both sides */
        s->flags |= SF_FINST_D;
      }
    }
  }
}


DECLARE_TYPED_POOL(pool_head_http_txn, "http_txn", struct http_txn);

/*
 * Local variables:
 *  c-indent-level: 8
 *  c-basic-offset: 8
 * End:
 */

Coverage Report

Created: 2026-06-30 06:43