/src/freeradius-server/src/lib/server/client.c

Source
/*
 *   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.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

/**
 * $Id: 4702a52f7ee404568b81d8f124e7e5b63e1213b9 $
 * @file src/lib/server/client.c
 * @brief Manage clients allowed to communicate with the server.
 *
 * @copyright 2015 Arran Cudbard-Bell (a.cudbardb@freeradius.org)
 * @copyright 2000,2006 The FreeRADIUS server project
 * @copyright 2000 Alan DeKok (aland@freeradius.org)
 * @copyright 2000 Miquel van Smoorenburg (miquels@cistron.nl)
 */
RCSID("$Id: 4702a52f7ee404568b81d8f124e7e5b63e1213b9 $")

#include <freeradius-devel/protocol/freeradius/freeradius.internal.h>
#include <freeradius-devel/server/cf_file.h>
#include <freeradius-devel/server/cf_parse.h>
#include <freeradius-devel/server/client.h>
#include <freeradius-devel/server/main_config.h>
#include <freeradius-devel/server/module.h>
#include <freeradius-devel/server/virtual_servers.h>
#include <freeradius-devel/unlang/call.h>

#include <freeradius-devel/util/base16.h>
#include <freeradius-devel/util/misc.h>
#include <freeradius-devel/util/trie.h>

#include <fcntl.h>
#include <sys/stat.h>

//#define WITH_TRIE (1)

/** Group of clients
 *
 */
struct fr_client_list_s {
  char const  *name;      //!< Name of the client list.
#ifdef WITH_TRIE
  fr_trie_t *v4_udp;
  fr_trie_t *v6_udp;
  fr_trie_t *v4_tcp;
  fr_trie_t *v6_tcp;
#else
  fr_rb_tree_t  *tree[129];
#endif
};

static fr_client_list_t *root_clients = NULL; //!< Global client list.

#ifndef WITH_TRIE
static fr_cmp_ret_t client_cmp(void const *one, void const *two)
{
  fr_cmp_ret_t ret;
  fr_client_t const *a = one;
  fr_client_t const *b = two;

  ret = fr_ipaddr_cmp(&a->ipaddr, &b->ipaddr);
  if (ret != 0) return ret;

  /*
   *  0 is "wildcard", or "both" protocols
   */
  if ((a->proto == IPPROTO_IP) || (b->proto == IPPROTO_IP)) return CMP_EQ;

  return CMP(a->proto, b->proto);
}

#endif

void client_list_free(void)
{
  TALLOC_FREE(root_clients);
}

/** Free a client
 *
 *  It's up to the caller to ensure that it's deleted from any fr_client_list_t.
 */
void client_free(fr_client_t *client)
{
  if (!client) return;

  talloc_free(client);
}

/** Return a new client list
 *
 * @note The container won't contain any clients.
 *
 * @return
 *  - New client list on success.
 *  - NULL on error (OOM).
 */
fr_client_list_t *client_list_init(CONF_SECTION *cs)
{
  fr_client_list_t *clients = talloc_zero(cs, fr_client_list_t);

  if (!clients) return NULL;

  clients->name = talloc_strdup(clients, cs ? cf_section_name1(cs) : "root");

#ifdef WITH_TRIE
  clients->v4_udp = fr_trie_alloc(clients, NULL, NULL);
  if (!clients->v4_udp) {
    talloc_free(clients);
    return NULL;
  }

  clients->v6_udp = fr_trie_alloc(clients, NULL, NULL);
  if (!clients->v6_udp) {
    talloc_free(clients);
    return NULL;
  }

  clients->v4_tcp = fr_trie_alloc(clients, NULL, NULL);
  if (!clients->v4_tcp) {
    talloc_free(clients);
    return NULL;
  }

  clients->v6_tcp = fr_trie_alloc(clients, NULL, NULL);
  if (!clients->v6_tcp) {
    talloc_free(clients);
    return NULL;
  }
#endif  /* WITH_TRIE */

  return clients;
}

#ifdef WITH_TRIE
/*
 *  @todo - either support client definitions where "proto = *",
 *  or update this code to allow for that.  i.e. we create yet
 *  another set of v4/v6 tries, for "proto = *" clients.  And then
 *  do lookups there, too.  Or, just unify the udp/tcp tries, and
 *  instead do post-processing?  Though those two clients can have
 *  different secrets... and the trie code doesn't allow 2
 *  fr_trie_user_t nodes in a row.  So we would have to instead
 *  handle that ourselves, with a wrapper around the fr_client_t
 *  structure that does udp/tcp/wildcard demultiplexing
 */
static fr_trie_t *clients_trie(fr_client_list_t const *clients, fr_ipaddr_t const *ipaddr,
             int proto)
{
  if (ipaddr->af == AF_INET) {
    if (proto == IPPROTO_TCP) return clients->v4_tcp;

    return clients->v4_udp;
  }

  fr_assert(ipaddr->af == AF_INET6);

  if (proto == IPPROTO_TCP) return clients->v6_tcp;

  return clients->v6_udp;
}
#endif  /* WITH_TRIE */

/** Add a client to a fr_client_list_t
 *
 * @param clients list to add client to, may be NULL if global client list is being used.
 * @param client to add.
 * @return
 *  - true on success.
 *  - false on failure.
 */
bool client_add(fr_client_list_t *clients, fr_client_t *client)
{
#ifdef WITH_TRIE
  fr_trie_t *trie;
#else
#endif
  fr_client_t *old;
  char buffer[FR_IPADDR_PREFIX_STRLEN];

  if (!client) return false;

  /*
   *  Hack to fixup wildcard clients
   *
   *  If the IP is all zeros, with a 32 or 128 bit netmask
   *  assume the user meant to configure 0.0.0.0/0 instead
   *  of 0.0.0.0/32 - which would require the src IP of
   *  the client to be all zeros.
   */
  if (fr_ipaddr_is_inaddr_any(&client->ipaddr) == 1) switch (client->ipaddr.af) {
  case AF_INET:
    if (client->ipaddr.prefix == 32) client->ipaddr.prefix = 0;
    break;

  case AF_INET6:
    if (client->ipaddr.prefix == 128) client->ipaddr.prefix = 0;
    break;

  default:
    fr_assert(0);
  }

  fr_inet_ntop_prefix(buffer, sizeof(buffer), &client->ipaddr);
  DEBUG3("Adding client %s (%s) to prefix tree %i", buffer, client->longname, client->ipaddr.prefix);

  /*
   *  If "clients" is NULL, it means add to the global list,
   *  unless we're trying to add it to a virtual server...
   */
  if (!clients) {
    if (client->server != NULL) {
      CONF_SECTION *cs;
      CONF_SECTION *subcs;

      if (!client->cs) {
        ERROR("Failed to find configuration section in client.  Ignoring 'virtual_server' directive");
        return false;
      }

      cs = cf_section_find(cf_root(client->cs), "server", client->server);
      if (!cs) {
        ERROR("Failed to find virtual server %s", client->server);
        return false;
      }

      /*
       *  If this server has no "listen" section, add the clients
       *  to the global client list.
       */
      subcs = cf_section_find(cs, "listen", NULL);
      if (!subcs) goto global_clients;

      /*
       *  If the client list already exists, use that.
       *  Otherwise, create a new client list.
       */
      clients = cf_data_value(cf_data_find(cs, fr_client_list_t, NULL));
      if (!clients) {
        MEM(clients = client_list_init(cs));
        if (!cf_data_add(cs, clients, NULL, false)) {
          ERROR("Failed to associate clients with virtual server %s", client->server);
          talloc_free(clients);
          return false;
        }
      }

    } else {
    global_clients:
      /*
       *  Initialize the global list, if not done already.
       */
      if (!root_clients) {
        root_clients = client_list_init(NULL);
        if (!root_clients) return false;
      }
      clients = root_clients;
    }
  }

#define namecmp(a) ((!old->a && !client->a) || (old->a && client->a && (strcmp(old->a, client->a) == 0)))

#ifdef WITH_TRIE
  trie = clients_trie(clients, &client->ipaddr, client->proto);

  /*
   *  Cannot insert the same client twice.
   */
  old = fr_trie_match_by_key(trie, &client->ipaddr.addr, client->ipaddr.prefix);

#else  /* WITH_TRIE */

  if (!clients->tree[client->ipaddr.prefix]) {
    clients->tree[client->ipaddr.prefix] = fr_rb_inline_talloc_alloc(clients, fr_client_t, node, client_cmp,
                     NULL);
    if (!clients->tree[client->ipaddr.prefix]) {
      return false;
    }
  }

  fr_rb_find((void **)&old, clients->tree[client->ipaddr.prefix], client);
#endif
  if (old) {
    /*
     *  If it's a complete duplicate, then free the new
     *  one, and return "OK".
     */
    if (namecmp(longname) && namecmp(secret) &&
        namecmp(shortname) && namecmp(nas_type) &&
        namecmp(server) &&
        (old->require_message_authenticator == client->require_message_authenticator)) {
      WARN("Ignoring duplicate client %s", client->longname);
      client_free(client);
      return true;
    }

    ERROR("Failed to add duplicate client %s", client->shortname);
    return false;
  }
#undef namecmp

#ifdef WITH_TRIE
  /*
   *  Other error adding client: likely is fatal.
   */
  if (fr_trie_insert_by_key(trie, &client->ipaddr.addr, client->ipaddr.prefix, client) < 0) {
    return false;
  }
#else
  if (fr_rb_insert(clients->tree[client->ipaddr.prefix], client) != 0) {
    return false;
  }
#endif

  /*
   *  @todo - do we want to do this for dynamic clients?
   */
  (void) talloc_steal(clients, client); /* reparent it */

  return true;
}


void client_delete(fr_client_list_t *clients, fr_client_t *client)
{
#ifdef WITH_TRIE
  fr_trie_t *trie;
#endif

  if (!client) return;

  if (!clients) clients = root_clients;

  fr_assert(client->ipaddr.prefix <= 128);

#ifdef WITH_TRIE
  trie = clients_trie(clients, &client->ipaddr, client->proto);

  /*
   *  Don't free the client.  The caller is responsible for that.
   */
  (void) fr_trie_remove_by_key(trie, &client->ipaddr.addr, client->ipaddr.prefix);
#else

  if (!clients->tree[client->ipaddr.prefix]) return;

  (void) fr_rb_delete(clients->tree[client->ipaddr.prefix], client);
#endif
}

fr_client_t *client_findbynumber(UNUSED const fr_client_list_t *clients, UNUSED int number)
{
  return NULL;
}


/*
 *  Find a client in the fr_client_t list.
 */
fr_client_t *client_find(fr_client_list_t const *clients, fr_ipaddr_t const *ipaddr, int proto)
{
#ifdef WITH_TRIE
  fr_trie_t *trie;
#else
  int i, max;
  fr_client_t my_client, *client;
#endif

  if (!clients) clients = root_clients;

  if (!clients || !ipaddr) return NULL;

#ifdef WITH_TRIE
  trie = clients_trie(clients, ipaddr, proto);

  return fr_trie_lookup_by_key(trie, &ipaddr->addr, ipaddr->prefix);
#else

  if (ipaddr->af == AF_INET) {
    max = 32;
  } else {
    max = 128;
  }

  if (max > ipaddr->prefix) max = ipaddr->prefix;

  my_client.proto = proto;
  for (i = max; i >= 0; i--) {
    if (!clients->tree[i]) continue;

    my_client.ipaddr = *ipaddr;
    fr_ipaddr_mask(&my_client.ipaddr, i);
    fr_rb_find((void **)&client, clients->tree[i], &my_client);
    if (client) {
      return client;
    }
  }

  return NULL;
#endif
}

static fr_ipaddr_t cl_ipaddr;
static char const *cl_srcipaddr = NULL;
static char const *hs_proto = NULL;

static conf_parser_t limit_config[] = {
  { FR_CONF_OFFSET("max_connections", fr_client_t, limit.max_connections), .dflt = "16" },

  { FR_CONF_OFFSET("lifetime", fr_client_t, limit.lifetime), .dflt = "0" },

  { FR_CONF_OFFSET("idle_timeout", fr_client_t, limit.idle_timeout), .dflt = "30s" },
  CONF_PARSER_TERMINATOR
};

static const conf_parser_t client_config[] = {
  { FR_CONF_POINTER("ipaddr", FR_TYPE_COMBO_IP_PREFIX, 0, &cl_ipaddr) },
  { FR_CONF_POINTER("ipv4addr", FR_TYPE_IPV4_PREFIX, 0, &cl_ipaddr) },
  { FR_CONF_POINTER("ipv6addr", FR_TYPE_IPV6_PREFIX, 0, &cl_ipaddr) },

  { FR_CONF_POINTER("src_ipaddr", FR_TYPE_STRING, 0, &cl_srcipaddr) },

  { FR_CONF_OFFSET_FLAGS("secret", CONF_FLAG_SECRET, fr_client_t, secret) },
  { FR_CONF_OFFSET("shortname", fr_client_t, shortname) },

  { FR_CONF_OFFSET("nas_type", fr_client_t, nas_type) },

  { FR_CONF_OFFSET_IS_SET("require_message_authenticator", FR_TYPE_UINT8, 0, fr_client_t, require_message_authenticator),
    .func = cf_table_parse_uint8,
    .uctx = &(cf_table_parse_ctx_t){ .table = fr_radius_require_ma_table, .len = &fr_radius_require_ma_table_len },
    .dflt = "no" },

  { FR_CONF_OFFSET_IS_SET("limit_proxy_state", FR_TYPE_UINT8, 0, fr_client_t, limit_proxy_state),
    .func = cf_table_parse_uint8,
    .uctx = &(cf_table_parse_ctx_t){ .table = fr_radius_limit_proxy_state_table, .len = &fr_radius_limit_proxy_state_table_len },
    .dflt = "auto" },

  { FR_CONF_OFFSET("protocol_error", fr_client_t, protocol_error) },

  { FR_CONF_OFFSET("response_window", fr_client_t, response_window) },

#ifdef NAS_VIOLATES_RFC
  /*
   *  For vendors who violate the RFCs and go out of their way to make their systems vulnerable.
   */
  { FR_CONF_OFFSET("nas_violates_message_authenticator_rfc", fr_client_t, allow_vulnerable_clients) },
#endif

  { FR_CONF_POINTER("proto", FR_TYPE_STRING, 0, &hs_proto) },
  { FR_CONF_POINTER("limit", 0, CONF_FLAG_SUBSECTION, NULL), .subcs = (void const *) limit_config },

  CONF_PARSER_TERMINATOR
};

/** Create a list of clients from a client section
 *
 * Iterates over all client definitions in the specified section, adding them to a client list.
 */
#ifdef WITH_TLS
#define TLS_UNUSED
#else
#define TLS_UNUSED UNUSED
#endif

fr_client_list_t *client_list_parse_section(CONF_SECTION *section, int proto, TLS_UNUSED bool tls_required)
{
  bool    global = false;
  CONF_SECTION  *cs = NULL;
  fr_client_t *c = NULL;
  fr_client_list_t  *clients = NULL;
  CONF_SECTION  *server_cs = NULL;
  char const  *cache_name;

  /*
   *  Key the cached list by protocol.  The section walk below
   *  filters out client definitions whose proto doesn't match
   *  the caller's, so caching the filtered list under a single
   *  key would let whichever listener instantiated first poison
   *  the cache for the other.  In particular the UDP listener
   *  would reuse a TCP-filtered list (with UDP-default clients
   *  dropped) and never see its own clients.
   */
  switch (proto) {
  case IPPROTO_UDP:
    cache_name = "udp";
    break;

  case IPPROTO_TCP:
    cache_name = "tcp";
    break;

  default:
    /*
     *  proto == 0 is the unfiltered / global path
     *  (main_config.c passes 0 for root clients).
     */
    cache_name = NULL;
    break;
  }

  /*
   *  Be forgiving.  If there's already a clients, return
   *  it.  Otherwise create a new one.
   */
  clients = cf_data_value(cf_data_find(section, fr_client_list_t, cache_name));
  if (clients) return clients;

  /*
   *  Parent the client list from the section.
   */
  clients = client_list_init(section);
  if (!clients) return NULL;

  /*
   *  If the section is hung off the config root, this is
   *  the global client list, else it's virtual server
   *  specific client list.
   */
  if (cf_root(section) == section) global = true;

  if (strcmp("server", cf_section_name1(section)) == 0) server_cs = section;

  /*
   *  Iterate over all the clients in the section, adding
   *  them to the client list.
   */
  while ((cs = cf_section_find_next(section, cs, "client", CF_IDENT_ANY))) {
    /*
     *  Check this before parsing the client.
     */
    if (proto) {
      CONF_PAIR *cp;
      int client_proto = IPPROTO_UDP;

      cp = cf_pair_find(cs, "proto");
      if (cp) {
        char const *value = cf_pair_value(cp);

        if (!value) {
          cf_log_err(cs, "'proto' field must have a value");
          talloc_free(clients);
          return NULL;
        }

        if (strcmp(value, "udp") == 0) {
          /* do nothing */

        } else if (strcmp(value, "tcp") == 0) {
          client_proto = IPPROTO_TCP;
#ifdef WITH_TLS
        } else if (strcmp(value, "tls") == 0) {
          client_proto = IPPROTO_TCP;
#endif
        } else if (strcmp(value, "*") == 0) {
          client_proto = IPPROTO_IP; /* fake for dual */
        } else {
          cf_log_err(cs, "Unknown proto \"%s\".", value);
          talloc_free(clients);
          return NULL;
        }
      }

      /*
       *  We don't have "proto = *", so the
       *  protocol MUST match what the caller
       *  asked for.  Otherwise, we ignore the
       *  client.
       */
      if ((client_proto != IPPROTO_IP) && (proto != client_proto)) continue;
    }


    c = client_afrom_cs(cs, cs, server_cs, 0);
    if (!c) {
    error:
      client_free(c);
      talloc_free(clients);
      return NULL;
    }

    /*
     *  TCP sockets are always connected.
     */
    c->use_connected |= (c->proto == IPPROTO_TCP);

#ifdef WITH_TLS
    /*
     *  TLS clients CANNOT use non-TLS listeners.
     *  non-TLS clients CANNOT use TLS listeners.
     */
    if (tls_required != c->tls_required) {
      cf_log_err(cs, "Client does not have the same TLS configuration as the listener");
      goto error;
    }
#endif

    if (!client_add(clients, c)) {
      cf_log_err(cs, "Failed to add client %s", cf_section_name2(cs));
      goto error;
    }

    cf_item_mark_parsed(cs);
  }

  /*
   *  Associate the clients structure with the section,
   *  keyed by protocol so a per-proto listener's filtered
   *  list doesn't shadow another proto's.
   */
  if (!cf_data_add(section, clients, cache_name, false)) {
    cf_log_err(section, "Failed to associate clients with section %s", cf_section_name1(section));
    talloc_free(clients);
    return NULL;
  }

  /*
   *  Replace the global list of clients with the new one.
   *  The old one is still referenced from the original
   *  configuration, and will be freed when that is freed.
   */
  if (global) root_clients = clients;

  return clients;
}

/** Create a client CONF_SECTION using a mapping section to map values from a result set to client attributes
 *
 * If we hit a CONF_SECTION we recurse and process its CONF_PAIRS too.
 *
 * @note Caller should free CONF_SECTION passed in as out, on error.
 *   Contents of that section will be in an undefined state.
 *
 * @param[in,out] out Section to perform mapping on. Either the root of the client config, or a parent section
 *  (when this function is called recursively).
 *  Should be alloced with cf_section_alloc, or if there's a separate template section, the
 *  result of calling cf_section_dup on that section.
 * @param[in] map section.
 * @param[in] func to call to retrieve CONF_PAIR values. Must return a talloced buffer containing the value.
 * @param[in] data to pass to func, usually a result pointer.
 * @return
 *  - 0 on success.
 *  - -1 on failure.
 */
int client_map_section(CONF_SECTION *out, CONF_SECTION const *map, client_value_cb_t func, void *data)
{
  CONF_ITEM const *ci;

  for (ci = cf_item_next(map, NULL);
       ci != NULL;
       ci = cf_item_next(map, ci)) {
        CONF_PAIR const *cp;
        CONF_PAIR *old;
        char *value;
    char const *attr;

    /*
     *  Recursively process map subsection
     */
    if (cf_item_is_section(ci)) {
      CONF_SECTION *cs, *cc;

      cs = cf_item_to_section(ci);
      /*
       *  Use pre-existing section or alloc a new one
       */
      cc = cf_section_find(out, cf_section_name1(cs), cf_section_name2(cs));
      if (!cc) {
        cc = cf_section_alloc(out, out, cf_section_name1(cs), cf_section_name2(cs));
        if (!cc) return -1;
      }

      if (client_map_section(cc, cs, func, data) < 0) return -1;
      continue;
    }

    cp = cf_item_to_pair(ci);
    attr = cf_pair_attr(cp);

    /*
     *  The callback can return 0 (success) and not provide a value
     *  in which case we skip the mapping pair.
     *
     *  Or return -1 in which case we error out.
     */
    if (func(&value, cp, data) < 0) {
      cf_log_err(out, "Failed performing mapping \"%s\" = \"%s\"", attr, cf_pair_value(cp));
      return -1;
    }
    if (!value) continue;

    /*
     *  Replace an existing CONF_PAIR
     */
    old = cf_pair_find(out, attr);
    if (old) {
      cf_pair_replace(out, old, value);
      talloc_free(value);
      continue;
    }

    /*
     *  ...or add a new CONF_PAIR
     */
    cp = cf_pair_alloc(out, attr, value, T_OP_SET, T_BARE_WORD, T_SINGLE_QUOTED_STRING);
    if (!cp) {
      cf_log_err(out, "Failed allocing pair \"%s\" = \"%s\"", attr, value);
      talloc_free(value);
      return -1;
    }
    talloc_free(value);
  }

  return 0;
}

/** Allocate a new client from a config section
 *
 * @param ctx to allocate new clients in.
 * @param cs to process as a client.
 * @param server_cs The virtual server that this client belongs to.
 * @param extra 0                 allocate sizeof(fr_client_t) bytes
 *              >sizeof(client_t) number of bytes to allocate
 * @return new fr_client_t struct.
 */
fr_client_t *client_afrom_cs(TALLOC_CTX *ctx, CONF_SECTION *cs, CONF_SECTION *server_cs, size_t extra)
{
  fr_client_t *c;
  char const  *name2;
  CONF_PAIR *cp;

  name2 = cf_section_name2(cs);
  if (!name2) {
    cf_log_err(cs, "Missing client name");
    return NULL;
  }

  /*
   *  The size is fine.. Let's create the buffer
   */
  if (!extra) {
    c = talloc_zero(ctx, fr_client_t);
    if (!c) return NULL;
  } else {
    fr_assert(extra > sizeof(fr_client_t));

    c = (fr_client_t *) talloc_zero_array(ctx, uint8_t, extra);
    if (!c) return NULL;

    talloc_set_name_const(c, "fr_client_t");
  }

  c->cs = cs;

  memset(&cl_ipaddr, 0, sizeof(cl_ipaddr));
  if (cf_section_rules_push(cs, client_config) < 0) goto error;

  if (cf_section_parse(c, c, cs) < 0) {
    cf_log_err(cs, "Error parsing client section");
  error:
    client_free(c);
    hs_proto = NULL;
    cl_srcipaddr = NULL;
    return NULL;
  }

  /*
   *  Allow for binary secrets.
   */
  cp = cf_pair_find(cs, "secret");
  if (cp && (cf_pair_operator(cp) == T_BARE_WORD)) {
    char const *value;

    value = cf_pair_value(cp);
    if ((value[0] == '0') && (value[1] == 'x')) {
      size_t bin_len, hex_len, converted;
      uint8_t *bin;

      /*
       *  '0x...' plus trailing NUL.
       */
      hex_len = talloc_array_length(value) - 3;
      bin_len = (hex_len / 2) + 1;
      MEM(bin = talloc_array(c, uint8_t, bin_len));
      converted = fr_base16_decode(NULL,
                 &FR_DBUFF_TMP(bin, bin_len),
                 &FR_SBUFF_IN(value + 2, hex_len), false);
      if (converted < (bin_len - 1)) {
        cf_log_err(cs, "Invalid hex string in shared secret");
        goto error;
      }

      talloc_const_free(c->secret);
      c->secret = (char const *) bin;
    }
  }

  /*
   *  Find the virtual server for this client.
   */
  if (c->server) {
    virtual_server_t const *vs;
    if (server_cs) {
      cf_log_err(cs, "Clients inside of a 'server' section cannot point to a server");
      goto error;
    }

    vs = virtual_server_find(c->server);
    if (!vs) goto error;

    c->server_cs = virtual_server_cs(vs);
    if (!c->server_cs) {
      cf_log_err(cs, "Failed to find virtual server %s", c->server);
      goto error;
    }

  } else if (server_cs) {
    c->server = cf_section_name2(server_cs);
    c->server_cs = server_cs;

  } /* else don't set c->server or c->server_cs, we will use listener->server */

  /*
   *  Newer style client definitions with either ipaddr or ipaddr6
   *  config items.
   */
  if (cf_pair_find(cs, "ipaddr") || cf_pair_find(cs, "ipv4addr") || cf_pair_find(cs, "ipv6addr")) {
    char buffer[128];

    /*
     *  Sets ipv4/ipv6 address and prefix.
     */
    c->ipaddr = cl_ipaddr;

    /*
     *  Set the long name to be the result of a reverse lookup on the IP address.
     */
    fr_inet_ntoh(&c->ipaddr, buffer, sizeof(buffer));
    c->longname = talloc_strdup(c, buffer);

    /*
     *  Set the short name to the name2.
     */
    if (!c->shortname) c->shortname = talloc_strdup(c, name2);
  /*
   *  No "ipaddr" or "ipv6addr", use old-style "client <ipaddr> {" syntax.
   */
  } else {
    cf_log_err(cs, "No 'ipaddr' or 'ipv4addr' or 'ipv6addr' configuration "
            "directive found in client %s", name2);
    goto error;
  }

  c->proto = IPPROTO_UDP;
  if (hs_proto) {
    if (strcmp(hs_proto, "udp") == 0) {
      hs_proto = NULL;

    } else if (strcmp(hs_proto, "tcp") == 0) {
      hs_proto = NULL;
      c->proto = IPPROTO_TCP;
#ifdef WITH_TLS
    } else if (strcmp(hs_proto, "tls") == 0) {
      hs_proto = NULL;
      c->proto = IPPROTO_TCP;
      c->tls_required = true;

#endif
    } else if (strcmp(hs_proto, "*") == 0) {
      hs_proto = NULL;
      c->proto = IPPROTO_IP; /* fake for dual */
    } else {
      cf_log_err(cs, "Unknown proto \"%s\".", hs_proto);
      goto error;
    }
  }

  /*
   *  If a src_ipaddr is specified, when we send the return packet
   *  we will use this address instead of the src from the
   *  request.
   */
  if (cl_srcipaddr) {
    switch (c->ipaddr.af) {
    case AF_INET:
      if (fr_inet_pton4(&c->src_ipaddr, cl_srcipaddr, -1, true, false, true) < 0) {
        cf_log_perr(cs, "Failed parsing src_ipaddr");
        goto error;
      }
      break;

    case AF_INET6:
      if (fr_inet_pton6(&c->src_ipaddr, cl_srcipaddr, -1, true, false, true) < 0) {
        cf_log_perr(cs, "Failed parsing src_ipaddr");
        goto error;
      }
      break;
    default:
      cf_log_err(cs, "ipaddr was not defined");
      goto error;
    }
    cl_srcipaddr = NULL;
  } else {
    c->src_ipaddr.af = c->ipaddr.af; /* leave the rest as IFADDR_ANY */
  }

  /*
   *  A response_window of zero is OK, and means that it's
   *  ignored by the rest of the server timers.
   */
  if (fr_time_delta_ispos(c->response_window)) {
    FR_TIME_DELTA_BOUND_CHECK("response_window", c->response_window, >=, fr_time_delta_from_usec(1000));
    FR_TIME_DELTA_BOUND_CHECK("response_window", c->response_window, <=, fr_time_delta_from_sec(60));
    FR_TIME_DELTA_BOUND_CHECK("response_window", c->response_window, <=, main_config->worker.max_request_time);
  }

#ifdef WITH_TLS
  /*
   *  If the client is TLS only, the secret can be
   *  omitted.  When omitted, it's hard-coded to
   *  "radsec".  See RFC 6614.
   */
  if (c->tls_required) {
    if (c->secret) {
      if (strcmp(c->secret, "radsec") != 0) {
        cf_log_warn(cs, "'secret' is not 'radsec' for TLS");
        cf_log_warn(cs, "Packets may not be processed correctly!");
      }
    } else {
      c->secret = talloc_strdup(cs, "radsec");
    }
  }
#endif

  if ((c->proto == IPPROTO_TCP) || (c->proto == IPPROTO_IP)) {
    if (fr_time_delta_ispos(c->limit.idle_timeout) && fr_time_delta_lt(c->limit.idle_timeout, fr_time_delta_from_sec(5)))
      c->limit.idle_timeout = fr_time_delta_from_sec(5);
    if (fr_time_delta_ispos(c->limit.lifetime) && (fr_time_delta_lt(c->limit.lifetime, fr_time_delta_from_sec(5))))
      c->limit.lifetime = fr_time_delta_from_sec(5);
    if (fr_time_delta_ispos(c->limit.lifetime) && (fr_time_delta_lt(c->limit.idle_timeout, c->limit.lifetime)))
      c->limit.idle_timeout = fr_time_delta_wrap(0);
  }

  cf_item_mark_parsed(cs);
  return c;
}

/** Create a new client, consuming all attributes in the control list of the request
 *
 * @param ctx the talloc context
 * @param request containing the client attributes.
 * @return
 *  - New client on success.
 *  - NULL on error.
 */
fr_client_t *client_afrom_request(TALLOC_CTX *ctx, request_t *request)
{
  static int  cnt;
  CONF_SECTION  *cs;
  fr_client_t *c;
  fr_sbuff_t  *tmp;

  if (!request) return NULL;

  FR_SBUFF_TALLOC_THREAD_LOCAL(&tmp, 128, SIZE_MAX);

  if (unlikely(fr_sbuff_in_sprintf(tmp, "dynamic_%i_", cnt++) <= 0)) {
  name_error:
    RERROR("Failed to generate dynamic client name");
    return NULL;
  }
  if (unlikely(fr_value_box_print(tmp, fr_box_ipaddr(request->packet->socket.inet.src_ipaddr), NULL) <= 0)) goto name_error;
  fr_sbuff_set_to_start(tmp);

  cs = cf_section_alloc(ctx, NULL, "client", fr_sbuff_current(tmp));

  RDEBUG2("Converting control.FreeRADIUS-Client-* to client {...} section");
  RINDENT();

  fr_pair_list_foreach(&request->control_pairs, vp) {
    CONF_PAIR *cp = NULL;
    char const  *value;
    char const  *attr;
    fr_token_t  v_token = T_BARE_WORD;

    if (!fr_dict_attr_is_top_level(vp->da)) continue;

    switch (vp->da->attr) {
    case FR_FREERADIUS_CLIENT_IP_ADDRESS:
      attr = "ipv4addr";
    vb_to_str:
      fr_sbuff_set_to_start(tmp);
      if (unlikely(fr_pair_print_value_quoted(tmp, vp, T_BARE_WORD) < 0)) {
        RERROR("Failed to convert %pP to string", vp);
      error:
        talloc_free(cs);
        return NULL;
      }
      value = fr_sbuff_start(tmp);
      break;

    case FR_FREERADIUS_CLIENT_IP_PREFIX:
      attr = "ipv4addr";
      goto vb_to_str;

    case FR_FREERADIUS_CLIENT_IPV6_ADDRESS:
      attr = "ipv6addr";
      goto vb_to_str;

    case FR_FREERADIUS_CLIENT_IPV6_PREFIX:
      attr = "ipv6addr";
      goto vb_to_str;

    case FR_FREERADIUS_CLIENT_SECRET:
      attr = "secret";
      value = vp->vp_strvalue;
      break;

    case FR_FREERADIUS_CLIENT_NAS_TYPE:
      attr = "nas_type";
      value = vp->vp_strvalue;
      break;

    case FR_FREERADIUS_CLIENT_SHORTNAME:
      attr = "shortname";
      value = vp->vp_strvalue;
      break;

    case FR_FREERADIUS_CLIENT_SRC_IP_ADDRESS:
      attr = "src_ipaddr";
      goto vb_to_str;

    case FR_FREERADIUS_CLIENT_REQUIRE_MA:
      attr = "require_message_authenticator";
      goto vb_to_str;

    case FR_FREERADIUS_CLIENT_LIMIT_PROXY_STATE:
      attr = "limit_proxy_state";
      goto vb_to_str;

    case FR_FREERADIUS_CLIENT_TRACK_CONNECTIONS:
      attr = "track_connections";
      goto vb_to_str;

    default:
      attr = vp->da->name;
      fr_sbuff_set_to_start(tmp);
      if (unlikely(fr_value_box_print(tmp, &vp->data, &fr_value_escape_single) < 0)) {
        RERROR("Failed printing value for %s", attr);
        goto error;
      }
      value = fr_sbuff_start(tmp);
      v_token = T_SINGLE_QUOTED_STRING;
      break;
    }

    cp = cf_pair_alloc(cs, attr, value, T_OP_SET, T_BARE_WORD, v_token);
    if (!cp) {
      RERROR("Error creating equivalent conf pair for %s", vp->da->name);
      goto error;
    }

    RDEBUG2("%s = %s", cf_pair_attr(cp), cf_pair_value(cp));
  }

  REXDENT();

  /*
   *  @todo - allow for setting a DIFFERENT virtual server,
   *  src IP, protocol, etc.  This should all be in TLVs..
   */
  c = client_afrom_cs(cs, cs, unlang_call_current(request), 0);
  if (!c) goto error;

  return c;
}

/** Read a single client from a file
 *
 * This function supports asynchronous runtime loading of clients.
 *
 * @param[in] filename    To read clients from.
 * @param[in] server_cs   of virtual server clients should be added to.
 * @param[in] check_dns   Check reverse lookup of IP address matches filename.
 * @return
 *  - The new client on success.
 *  - NULL on failure.
 */
fr_client_t *client_read(char const *filename, CONF_SECTION *server_cs, bool check_dns)
{
  char const  *p;
  fr_client_t *c;
  CONF_SECTION  *root_cs, *cs;
  char buffer[256];

  if (!filename) return NULL;

  root_cs = cf_section_alloc(NULL, NULL, "main", NULL);
  if (!root_cs) return NULL;

  if ((cf_file_read(root_cs, filename, false) < 0) || (cf_section_pass2(root_cs) < 0)) {
  error:
    talloc_free(root_cs);
    return NULL;
  }

  cs = cf_section_find(root_cs, "client", CF_IDENT_ANY);
  if (!cs) {
    ERROR("No \"client\" section found in client file");
    goto error;
  }

  c = client_afrom_cs(cs, cs, server_cs, 0);
  if (!c) goto error;

  /*
   *  Detach c from cs (breaking the cs -> c parent link), then make root_cs a child of c.  This
   *  avoids a talloc cycle (c -> root_cs -> cs -> c), and ensures that freeing c also frees root_cs
   *  and cs.
   */
  (void) talloc_steal(NULL, c);
  (void) talloc_steal(c, root_cs);

  p = strrchr(filename, FR_DIR_SEP);
  if (p) {
    p++;
  } else {
    p = filename;
  }

  if (!check_dns) return c;

  /*
   *  Additional validations
   */
  fr_inet_ntoh(&c->ipaddr, buffer, sizeof(buffer));
  if (strcmp(p, buffer) != 0) {
    ERROR("Invalid client definition in %s: IP address %s does not match name %s", filename, buffer, p);
    talloc_free(c); /* also frees root_cs and cs */
    return NULL;
  }

  return c;
}

/** Search up a list of requests trying to locate one which has a client
 *
 */
fr_client_t *client_from_request(request_t *request)
{
  fr_client_t *client;
  request_t *parent = request;

  do {
    client = parent->client;
  } while (!client && (parent = parent->parent));

  return client;
}

Coverage Report

Created: 2026-10-18 06:56