#include "git-compat-util.h"

#include "config.h"

#include "commit.h"

#include "date.h"

#include "gettext.h"

#include "hex.h"

#include "odb.h"

#include "pkt-line.h"

#include "sideband.h"

#include "run-command.h"

#include "remote.h"

#include "connect.h"

#include "send-pack.h"

#include "transport.h"

#include "version.h"

#include "oid-array.h"

#include "gpg-interface.h"

#include "shallow.h"

#include "parse-options.h"

#include "trace2.h"

#include "write-or-die.h"

int option_parse_push_signed(const struct option *opt,

           const char *arg, int unset)

{

  if (unset) {

    *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;

    return 0;

  }

  switch (git_parse_maybe_bool(arg)) {

  case 1:

    *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;

    return 0;

  case 0:

    *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;

    return 0;

  }

  if (!strcasecmp("if-asked", arg)) {

    *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;

    return 0;

  }

  die("bad %s argument: %s", opt->long_name, arg);

}

static void feed_object(struct repository *r,

      const struct object_id *oid, FILE *fh, int negative)

{

  if (negative && !odb_has_object(r->objects, oid, 0))

    return;

  if (negative)

    putc('^', fh);

  fputs(oid_to_hex(oid), fh);

  putc('\n', fh);

}

/*

 * Make a pack stream and spit it out into file descriptor fd

 */

static int pack_objects(struct repository *r,

      int fd, struct ref *refs, struct oid_array *advertised,

      struct oid_array *negotiated,

      struct send_pack_args *args)

{

  /*

   * The child becomes pack-objects --revs; we feed

   * the revision parameters to it via its stdin and

   * let its stdout go back to the other end.

   */

  struct child_process po = CHILD_PROCESS_INIT;

  FILE *po_in;

  int rc;

  trace2_region_enter("send_pack", "pack_objects", r);

  strvec_push(&po.args, "pack-objects");

  strvec_push(&po.args, "--all-progress-implied");

  strvec_push(&po.args, "--revs");

  strvec_push(&po.args, "--stdout");

  if (args->use_thin_pack)

    strvec_push(&po.args, "--thin");

  if (args->use_ofs_delta)

    strvec_push(&po.args, "--delta-base-offset");

  if (args->quiet || !args->progress)

    strvec_push(&po.args, "-q");

  if (args->progress)

    strvec_push(&po.args, "--progress");

  if (is_repository_shallow(r))

    strvec_push(&po.args, "--shallow");

  if (args->disable_bitmaps)

    strvec_push(&po.args, "--no-use-bitmap-index");

  po.in = -1;

  po.out = args->stateless_rpc ? -1 : fd;

  po.git_cmd = 1;

  po.clean_on_exit = 1;

  if (start_command(&po))

    die_errno("git pack-objects failed");

  /*

   * We feed the pack-objects we just spawned with revision

   * parameters by writing to the pipe.

   */

  po_in = xfdopen(po.in, "w");

  for (size_t i = 0; i < advertised->nr; i++)

    feed_object(r, &advertised->oid[i], po_in, 1);

  for (size_t i = 0; i < negotiated->nr; i++)

    feed_object(r, &negotiated->oid[i], po_in, 1);

  while (refs) {

    if (!is_null_oid(&refs->old_oid))

      feed_object(r, &refs->old_oid, po_in, 1);

    if (!is_null_oid(&refs->new_oid))

      feed_object(r, &refs->new_oid, po_in, 0);

    refs = refs->next;

  }

  fflush(po_in);

  if (ferror(po_in))

    die_errno("error writing to pack-objects");

  fclose(po_in);

  if (args->stateless_rpc) {

    char *buf = xmalloc(LARGE_PACKET_MAX);

    while (1) {

      ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);

      if (n <= 0)

        break;

      send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);

    }

    free(buf);

    close(po.out);

    po.out = -1;

  }

  rc = finish_command(&po);

  if (rc) {

    /*

     * For a normal non-zero exit, we assume pack-objects wrote

     * something useful to stderr. For death by signal, though,

     * we should mention it to the user. The exception is SIGPIPE

     * (141), because that's a normal occurrence if the remote end

     * hangs up (and we'll report that by trying to read the unpack

     * status).

     */

    if (rc > 128 && rc != 141)

      error("pack-objects died of signal %d", rc - 128);

    trace2_region_leave("send_pack", "pack_objects", r);

    return -1;

  }

  trace2_region_leave("send_pack", "pack_objects", r);

  return 0;

}

static int receive_unpack_status(struct packet_reader *reader)

{

  if (packet_reader_read(reader) != PACKET_READ_NORMAL)

    return error(_("unexpected flush packet while reading remote unpack status"));

  if (!skip_prefix(reader->line, "unpack ", &reader->line))

    return error(_("unable to parse remote unpack status: %s"), reader->line);

  if (strcmp(reader->line, "ok"))

    return error(_("remote unpack failed: %s"), reader->line);

  return 0;

}

static int receive_status(struct repository *r,

        struct packet_reader *reader, struct ref *refs)

{

  struct ref *hint;

  int ret;

  struct ref_push_report *report = NULL;

  int new_report = 0;

  int once = 0;

  trace2_region_enter("send_pack", "receive_status", r);

  hint = NULL;

  ret = receive_unpack_status(reader);

  while (1) {

    struct object_id old_oid, new_oid;

    const char *head;

    const char *refname;

    char *p;

    if (packet_reader_read(reader) != PACKET_READ_NORMAL)

      break;

    head = reader->line;

    p = strchr(head, ' ');

    if (!p) {

      error("invalid status line from remote: %s", reader->line);

      ret = -1;

      break;

    }

    *p++ = '\0';

    if (!strcmp(head, "option")) {

      const char *key, *val;

      if (!hint || !(report || new_report)) {

        if (!once++)

          error("'option' without a matching 'ok/ng' directive");

        ret = -1;

        continue;

      }

      if (new_report) {

        if (!hint->report) {

          CALLOC_ARRAY(hint->report, 1);

          report = hint->report;

        } else {

          report = hint->report;

          while (report->next)

            report = report->next;

          CALLOC_ARRAY(report->next, 1);

          report = report->next;

        }

        new_report = 0;

      }

      key = p;

      p = strchr(key, ' ');

      if (p)

        *p++ = '\0';

      val = p;

      if (!strcmp(key, "refname"))

        report->ref_name = xstrdup_or_null(val);

      else if (!strcmp(key, "old-oid") && val &&

         !parse_oid_hex_algop(val, &old_oid, &val, r->hash_algo))

        report->old_oid = oiddup(&old_oid);

      else if (!strcmp(key, "new-oid") && val &&

         !parse_oid_hex_algop(val, &new_oid, &val, r->hash_algo))

        report->new_oid = oiddup(&new_oid);

      else if (!strcmp(key, "forced-update"))

        report->forced_update = 1;

      continue;

    }

    report = NULL;

    new_report = 0;

    if (strcmp(head, "ok") && strcmp(head, "ng")) {

      error("invalid ref status from remote: %s", head);

      ret = -1;

      break;

    }

    refname = p;

    p = strchr(refname, ' ');

    if (p)

      *p++ = '\0';

    /* first try searching at our hint, falling back to all refs */

    if (hint)

      hint = find_ref_by_name(hint, refname);

    if (!hint)

      hint = find_ref_by_name(refs, refname);

    if (!hint) {

      warning("remote reported status on unknown ref: %s",

        refname);

      continue;

    }

    if (hint->status != REF_STATUS_EXPECTING_REPORT &&

        hint->status != REF_STATUS_OK &&

        hint->status != REF_STATUS_REMOTE_REJECT) {

      warning("remote reported status on unexpected ref: %s",

        refname);

      continue;

    }

    /*

     * Clients sending duplicate refs can cause the same value

     * to be overridden, causing a memory leak.

     */

    free(hint->remote_status);

    if (!strcmp(head, "ng")) {

      hint->status = REF_STATUS_REMOTE_REJECT;

      if (p)

        hint->remote_status = xstrdup(p);

      else

        hint->remote_status = xstrdup("failed");

    } else {

      hint->status = REF_STATUS_OK;

      hint->remote_status = xstrdup_or_null(p);

      new_report = 1;

    }

  }

  trace2_region_leave("send_pack", "receive_status", r);

  return ret;

}

static int sideband_demux(int in UNUSED, int out, void *data)

{

  int *fd = data, ret;

  if (async_with_fork())

    close(fd[1]);

  ret = recv_sideband("send-pack", fd[0], out);

  close(out);

  return ret;

}

static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)

{

  struct strbuf *sb = cb;

  if (graft->nr_parent == -1)

    packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));

  return 0;

}

static void advertise_shallow_grafts_buf(struct repository *r, struct strbuf *sb)

{

  if (!is_repository_shallow(r))

    return;

  for_each_commit_graft(advertise_shallow_grafts_cb, sb);

}

#define CHECK_REF_NO_PUSH -1

#define CHECK_REF_STATUS_REJECTED -2

#define CHECK_REF_UPTODATE -3

static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)

{

  if (!ref->peer_ref && !args->send_mirror)

    return CHECK_REF_NO_PUSH;

  /* Check for statuses set by set_ref_status_for_push() */

  switch (ref->status) {

  case REF_STATUS_REJECT_NONFASTFORWARD:

  case REF_STATUS_REJECT_ALREADY_EXISTS:

  case REF_STATUS_REJECT_FETCH_FIRST:

  case REF_STATUS_REJECT_NEEDS_FORCE:

  case REF_STATUS_REJECT_STALE:

  case REF_STATUS_REJECT_REMOTE_UPDATED:

  case REF_STATUS_REJECT_NODELETE:

    return CHECK_REF_STATUS_REJECTED;

  case REF_STATUS_UPTODATE:

    return CHECK_REF_UPTODATE;

  default:

  case REF_STATUS_EXPECTING_REPORT:

    /* already passed checks on the local side */

  case REF_STATUS_OK:

    /* of course this is OK */

    return 0;

  }

}

/*

 * the beginning of the next line, or the end of buffer.

 *

 * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and

 * convert many similar uses found by "git grep -A4 memchr".

 */

static const char *next_line(const char *line, size_t len)

{

  const char *nl = memchr(line, '\n', len);

  if (!nl)

    return line + len; /* incomplete line */

  return nl + 1;

}

static int generate_push_cert(struct strbuf *req_buf,

            const struct ref *remote_refs,

            struct send_pack_args *args,

            const char *cap_string,

            const char *push_cert_nonce)

{

  const struct ref *ref;

  struct string_list_item *item;

  char *signing_key_id = get_signing_key_id();

  char *signing_key = get_signing_key();

  const char *cp, *np;

  struct strbuf cert = STRBUF_INIT;

  int update_seen = 0;

  strbuf_addstr(&cert, "certificate version 0.1\n");

  strbuf_addf(&cert, "pusher %s ", signing_key_id);

  datestamp(&cert);

  strbuf_addch(&cert, '\n');

  if (args->url && *args->url) {

    char *anon_url = transport_anonymize_url(args->url);

    strbuf_addf(&cert, "pushee %s\n", anon_url);

    free(anon_url);

  }

  if (push_cert_nonce[0])

    strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);

  if (args->push_options)

    for_each_string_list_item(item, args->push_options)

      strbuf_addf(&cert, "push-option %s\n", item->string);

  strbuf_addstr(&cert, "\n");

  for (ref = remote_refs; ref; ref = ref->next) {

    if (check_to_send_update(ref, args) < 0)

      continue;

    update_seen = 1;

    strbuf_addf(&cert, "%s %s %s\n",

          oid_to_hex(&ref->old_oid),

          oid_to_hex(&ref->new_oid),

          ref->name);

  }

  if (!update_seen)

    goto free_return;

  if (sign_buffer(&cert, &cert, signing_key))

    die(_("failed to sign the push certificate"));

  packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);

  for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {

    np = next_line(cp, cert.buf + cert.len - cp);

    packet_buf_write(req_buf,

         "%.*s", (int)(np - cp), cp);

  }

  packet_buf_write(req_buf, "push-cert-end\n");

free_return:

  free(signing_key_id);

  free(signing_key);

  strbuf_release(&cert);

  return update_seen;

}

#define NONCE_LEN_LIMIT 256

static void reject_invalid_nonce(const char *nonce, int len)

{

  int i = 0;

  if (NONCE_LEN_LIMIT <= len)

    die("the receiving end asked to sign an invalid nonce <%.*s>",

        len, nonce);

  for (i = 0; i < len; i++) {

    int ch = nonce[i] & 0xFF;

    if (isalnum(ch) ||

        ch == '-' || ch == '.' ||

        ch == '/' || ch == '+' ||

        ch == '=' || ch == '_')

      continue;

    die("the receiving end asked to sign an invalid nonce <%.*s>",

        len, nonce);

  }

}

static void get_commons_through_negotiation(struct repository *r,

              const char *url,

              const struct ref *remote_refs,

              struct oid_array *commons)

{

  struct child_process child = CHILD_PROCESS_INIT;

  const struct ref *ref;

  int len = r->hash_algo->hexsz + 1; /* hash + NL */

  int nr_negotiation_tip = 0;

  child.git_cmd = 1;

  child.no_stdin = 1;

  child.out = -1;

  strvec_pushl(&child.args, "fetch", "--negotiate-only", NULL);

  for (ref = remote_refs; ref; ref = ref->next) {

    if (!is_null_oid(&ref->new_oid)) {

      strvec_pushf(&child.args, "--negotiation-tip=%s",

             oid_to_hex(&ref->new_oid));

      nr_negotiation_tip++;

    }

  }

  strvec_push(&child.args, url);

  if (!nr_negotiation_tip) {

    child_process_clear(&child);

    return;

  }

  if (start_command(&child))

    die(_("send-pack: unable to fork off fetch subprocess"));

  do {

    char hex_hash[GIT_MAX_HEXSZ + 1];

    int read_len = read_in_full(child.out, hex_hash, len);

    struct object_id oid;

    const char *end;

    if (!read_len)

      break;

    if (read_len != len)

      die("invalid length read %d", read_len);

    if (parse_oid_hex_algop(hex_hash, &oid, &end, r->hash_algo) || *end != '\n')

      die("invalid hash");

    oid_array_append(commons, &oid);

  } while (1);

  if (finish_command(&child)) {

    /*

     * The information that push negotiation provides is useful but

     * not mandatory.

     */

    warning(_("push negotiation failed; proceeding anyway with push"));

  }

}

int send_pack(struct repository *r,

        struct send_pack_args *args,

        int fd[], struct child_process *conn,

        struct ref *remote_refs,

        struct oid_array *extra_have)

{

  struct oid_array commons = OID_ARRAY_INIT;

  int in = fd[0];

  int out = fd[1];

  struct strbuf req_buf = STRBUF_INIT;

  struct strbuf cap_buf = STRBUF_INIT;

  struct ref *ref;

  int need_pack_data = 0;

  int allow_deleting_refs = 0;

  int status_report = 0;

  int use_sideband = 0;

  int quiet_supported = 0;

  int agent_supported = 0;

  int advertise_sid = 0;

  int push_negotiate = 0;

  int use_atomic = 0;

  int atomic_supported = 0;

  int use_push_options = 0;

  int push_options_supported = 0;

  int object_format_supported = 0;

  unsigned cmds_sent = 0;

  int ret;

  struct async demux;

  char *push_cert_nonce = NULL;

  struct packet_reader reader;

  int use_bitmaps;

  if (!remote_refs) {

    fprintf(stderr, "No refs in common and none specified; doing nothing.\n"

      "Perhaps you should specify a branch.\n");

    ret = 0;

    goto out;

  }

  repo_config_get_bool(r, "push.negotiate", &push_negotiate);

  if (push_negotiate) {

    trace2_region_enter("send_pack", "push_negotiate", r);

    get_commons_through_negotiation(r, args->url, remote_refs, &commons);

    trace2_region_leave("send_pack", "push_negotiate", r);

  }

  if (!repo_config_get_bool(r, "push.usebitmaps", &use_bitmaps))

    args->disable_bitmaps = !use_bitmaps;

  repo_config_get_bool(r, "transfer.advertisesid", &advertise_sid);

  /* Does the other end support the reporting? */

  if (server_supports("report-status-v2"))

    status_report = 2;

  else if (server_supports("report-status"))

    status_report = 1;

  if (server_supports("delete-refs"))

    allow_deleting_refs = 1;

  if (server_supports("ofs-delta"))

    args->use_ofs_delta = 1;

  if (server_supports("side-band-64k"))

    use_sideband = 1;

  if (server_supports("quiet"))

    quiet_supported = 1;

  if (server_supports("agent"))

    agent_supported = 1;

  if (!server_supports("session-id"))

    advertise_sid = 0;

  if (server_supports("no-thin"))

    args->use_thin_pack = 0;

  if (server_supports("atomic"))

    atomic_supported = 1;

  if (server_supports("push-options"))

    push_options_supported = 1;

  if (!server_supports_hash(r->hash_algo->name, &object_format_supported))

    die(_("the receiving end does not support this repository's hash algorithm"));

  if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {

    size_t len;

    const char *nonce = server_feature_value("push-cert", &len);

    if (nonce) {

      reject_invalid_nonce(nonce, len);

      push_cert_nonce = xmemdupz(nonce, len);

    } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {

      die(_("the receiving end does not support --signed push"));

    } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {

      warning(_("not sending a push certificate since the"

          " receiving end does not support --signed"

          " push"));

    }

  }

  if (args->atomic && !atomic_supported)

    die(_("the receiving end does not support --atomic push"));

  use_atomic = atomic_supported && args->atomic;

  if (args->push_options && !push_options_supported)

    die(_("the receiving end does not support push options"));

  use_push_options = push_options_supported && args->push_options;

  if (status_report == 1)

    strbuf_addstr(&cap_buf, " report-status");

  else if (status_report == 2)

    strbuf_addstr(&cap_buf, " report-status-v2");

  if (use_sideband)

    strbuf_addstr(&cap_buf, " side-band-64k");

  if (quiet_supported && (args->quiet || !args->progress))

    strbuf_addstr(&cap_buf, " quiet");

  if (use_atomic)

    strbuf_addstr(&cap_buf, " atomic");

  if (use_push_options)

    strbuf_addstr(&cap_buf, " push-options");

  if (object_format_supported)

    strbuf_addf(&cap_buf, " object-format=%s", r->hash_algo->name);

  if (agent_supported)

    strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());

  if (advertise_sid)

    strbuf_addf(&cap_buf, " session-id=%s", trace2_session_id());

  /*

   * NEEDSWORK: why does delete-refs have to be so specific to

   * send-pack machinery that set_ref_status_for_push() cannot

   * set this bit for us???

   */

  for (ref = remote_refs; ref; ref = ref->next)

    if (ref->deletion && !allow_deleting_refs)

      ref->status = REF_STATUS_REJECT_NODELETE;

  /*

   * Clear the status for each ref and see if we need to send

   * the pack data.

   */

  for (ref = remote_refs; ref; ref = ref->next) {

    switch (check_to_send_update(ref, args)) {

    case 0: /* no error */

      break;

    case CHECK_REF_STATUS_REJECTED:

      /*

       * When we know the server would reject a ref update if

       * we were to send it and we're trying to send the refs

       * atomically, abort the whole operation.

       */

      if (use_atomic) {

        reject_atomic_push(remote_refs, args->send_mirror);

        error("atomic push failed for ref %s. status: %d",

              ref->name, ref->status);

        ret = ERROR_SEND_PACK_BAD_REF_STATUS;

        packet_flush(out);

        goto out;

      }

      /* else fallthrough */

    default:

      continue;

    }

    if (!ref->deletion)

      need_pack_data = 1;

    if (args->dry_run || !status_report)

      ref->status = REF_STATUS_OK;

    else

      ref->status = REF_STATUS_EXPECTING_REPORT;

  }

  if (!args->dry_run)

    advertise_shallow_grafts_buf(r, &req_buf);

  /*

   * Finally, tell the other end!

   */

  if (!args->dry_run && push_cert_nonce) {

    cmds_sent = generate_push_cert(&req_buf, remote_refs, args,

                 cap_buf.buf, push_cert_nonce);

    trace2_printf("Generated push certificate");

  } else if (!args->dry_run) {

    for (ref = remote_refs; ref; ref = ref->next) {

      char *old_hex, *new_hex;

      if (check_to_send_update(ref, args) < 0)

        continue;

      old_hex = oid_to_hex(&ref->old_oid);

      new_hex = oid_to_hex(&ref->new_oid);

      if (!cmds_sent) {

        packet_buf_write(&req_buf,

             "%s %s %s%c%s",

             old_hex, new_hex, ref->name, 0,

             cap_buf.buf);

        cmds_sent = 1;

      } else {

        packet_buf_write(&req_buf, "%s %s %s",

             old_hex, new_hex, ref->name);

      }

    }

  }

  if (use_push_options) {

    struct string_list_item *item;

    packet_buf_flush(&req_buf);

    for_each_string_list_item(item, args->push_options)

      packet_buf_write(&req_buf, "%s", item->string);

  }

  if (args->stateless_rpc) {

    if (!args->dry_run && (cmds_sent || is_repository_shallow(r))) {

      packet_buf_flush(&req_buf);

      send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);

    }

  } else {

    write_or_die(out, req_buf.buf, req_buf.len);

    packet_flush(out);

  }

  if (use_sideband && cmds_sent) {

    memset(&demux, 0, sizeof(demux));

    demux.proc = sideband_demux;

    demux.data = fd;

    demux.out = -1;

    demux.isolate_sigpipe = 1;

    if (start_async(&demux))

      die("send-pack: unable to fork off sideband demultiplexer");

    in = demux.out;

  }

  packet_reader_init(&reader, in, NULL, 0,

         PACKET_READ_CHOMP_NEWLINE |

         PACKET_READ_DIE_ON_ERR_PACKET);

  if (need_pack_data && cmds_sent) {

    if (pack_objects(r, out, remote_refs, extra_have, &commons, args) < 0) {

      if (args->stateless_rpc)

        close(out);

      if (git_connection_is_socket(conn))

        shutdown(fd[0], SHUT_WR);

      /*

       * Do not even bother with the return value; we know we

       * are failing, and just want the error() side effects,

       * as well as marking refs with their remote status (if

       * we get one).

       */

      if (status_report)

        receive_status(r, &reader, remote_refs);

      if (use_sideband) {

        close(demux.out);

        finish_async(&demux);

      }

      fd[1] = -1;

      ret = -1;

      goto out;

    }

    if (!args->stateless_rpc)

      /* Closed by pack_objects() via start_command() */

      fd[1] = -1;

  }

  if (args->stateless_rpc && cmds_sent)

    packet_flush(out);

  if (status_report && cmds_sent)

    ret = receive_status(r, &reader, remote_refs);

  else

    ret = 0;

  if (args->stateless_rpc)

    packet_flush(out);

  if (use_sideband && cmds_sent) {

    close(demux.out);

    if (finish_async(&demux)) {

      error("error in sideband demultiplexer");

      ret = -1;

    }

  }

  if (ret < 0)

    goto out;

  for (ref = remote_refs; ref; ref = ref->next) {

    switch (ref->status) {

    case REF_STATUS_NONE:

    case REF_STATUS_UPTODATE:

    case REF_STATUS_OK:

      break;

    default:

      ret = ERROR_SEND_PACK_BAD_REF_STATUS;

      goto out;

    }

  }

  ret = 0;

out:

  oid_array_clear(&commons);

  strbuf_release(&req_buf);

  strbuf_release(&cap_buf);

  free(push_cert_nonce);

  return ret;

}