/*
 * cryptlink_serv - CRYPTLINK SERV message handler
 *        parv[0] == CRYPTLINK
 *        parv[1] == SERV
 *        parv[2] == server name
 *        parv[3] == keyphrase
 *        parv[4] == :server info (M-line)
 */
static void
cryptlink_serv(struct Client *client_p, struct Client *source_p,
               int parc, char *parv[])
{
  char info[REALLEN + 1];
  char *name;
  struct Client *target_p;
  char *key = client_p->localClient->out_key;
  unsigned char *b64_key;
  struct ConfItem *conf;
  struct AccessItem *aconf;
  char *encrypted;
  const char *p;
  int enc_len;

  /*
  if (client_p->name[0] != 0)
  return;
  */

  if ((parc < 5) || (*parv[4] == '\0'))
  {
    cryptlink_error(client_p, "SERV", "Invalid params",
                    "CRYPTLINK SERV - Invalid params");
    return;
  }

  if ((name = parse_cryptserv_args(client_p, parv, parc, info, key)) == NULL)
  {
    cryptlink_error(client_p, "SERV", "Invalid params",
                    "CRYPTLINK SERV - Invalid params");
    return;
  }

  /* CRYPTLINK SERV support => TS support */
  client_p->tsinfo = TS_DOESTS;

  if (bogus_host(name))
  {
    exit_client(client_p, client_p, "Bogus server name");
    return;
  }

  /* Now we just have to call check_server and everything should be
   * checked for us... -A1kmm. */
  switch (check_server(name, client_p, CHECK_SERVER_CRYPTLINK))
  {
    case -1:
      if (ConfigFileEntry.warn_no_nline)
      {
        cryptlink_error(client_p, "SERV",
          "Unauthorized server connection attempt: No entry for server",
          NULL);
      }
      exit_client(client_p, client_p, "Invalid server name");
      return;
      break;
    case -2:
      cryptlink_error(client_p, "SERV",
        "Unauthorized server connection attempt: CRYPTLINK not "
                                      "enabled on remote server",
        "CRYPTLINK not enabled");
      return;
      break;
    case -3:
      cryptlink_error(client_p, "SERV",
        "Unauthorized server connection attempt: Invalid host",
        "Invalid host");
      return;
      break;
  }

  if ((target_p = find_server(name)))
  {
    /*
     * This link is trying feed me a server that I already have
     * access through another path -- multiple paths not accepted
     * currently, kill this link immediately!!
     *
     * Rather than KILL the link which introduced it, KILL the
     * youngest of the two links. -avalon
     *
     * Definitely don't do that here. This is from an unregistered
     * connect - A1kmm.
     */
    cryptlink_error(client_p, "SERV",
                    "Attempt to re-introduce existing server",
                    "Server Exists");
    return;
  }

  if (ServerInfo.hub && IsCapable(client_p, CAP_LL))
  {
      if (IsCapable(client_p, CAP_HUB))
      {
          ClearCap(client_p,CAP_LL);
          sendto_realops_flags(UMODE_ALL, L_ALL,
               "*** LazyLinks to a hub from a hub, that's a no-no.");
      }
      else
      {
          client_p->localClient->serverMask = nextFreeMask();

          if(!client_p->localClient->serverMask)
          {
              sendto_realops_flags(UMODE_ALL, L_ALL,
                                   "serverMask is full!");
              /* try and negotiate a non LL connect */
              ClearCap(client_p,CAP_LL);
          }
      }
  }
  else if (IsCapable(client_p, CAP_LL))
  {
      if (!IsCapable(client_p, CAP_HUB))
      {
        ClearCap(client_p,CAP_LL);
        sendto_realops_flags(UMODE_ALL, L_ALL,
          "*** LazyLinks to a leaf from a leaf, that's a no-no.");
      }
  }

  conf = find_conf_name(&client_p->localClient->confs,
			name, SERVER_TYPE);
  if (conf == NULL)
  {
    cryptlink_error(client_p, "AUTH",
                    "Lost C-line for server",
                    "Lost C-line" );
    return;
  }

  /*
   * if we are connecting (Handshake), we already have the name from the
   * connect {} block in client_p->name
   */
  strlcpy(client_p->name, name, sizeof(client_p->name));

  p = info;

  if (!strncmp(info, "(H)", 3))
  {
    SetHidden(client_p);

    if ((p = strchr(info, ' ')) != NULL)
    {
      p++;
      if (*p == '\0')
        p = "(Unknown Location)";
    }
    else
      p = "(Unknown Location)";
  }

  strlcpy(client_p->info, p, sizeof(client_p->info));
  client_p->hopcount = 0;

  aconf = (struct AccessItem *)map_to_conf(conf);

  if (!(client_p->localClient->out_cipher ||
      (client_p->localClient->out_cipher = check_cipher(client_p, aconf))))
  {
    cryptlink_error(client_p, "AUTH",
                    "Couldn't find compatible cipher",
                    "Couldn't find compatible cipher");
    return;
  }

  encrypted = MyMalloc(RSA_size(ServerInfo.rsa_private_key));
  enc_len   = RSA_public_encrypt(client_p->localClient->out_cipher->keylen,
                               (unsigned char *)key,
                               (unsigned char *)encrypted,
                               aconf->rsa_public_key,
                               RSA_PKCS1_PADDING);

  if (enc_len <= 0)
  {
    report_crypto_errors();
    MyFree(encrypted);
    cryptlink_error(client_p, "AUTH",
                    "Couldn't encrypt data",
                    "Couldn't encrypt data");
    return;
  }

  base64_block(&b64_key, encrypted, enc_len);

  MyFree(encrypted);

  if (!IsWaitAuth(client_p))
  {
    cryptlink_init(client_p, conf, NULL);
  }

  sendto_one(client_p, "CRYPTLINK AUTH %s %s",
             client_p->localClient->out_cipher->name,
             b64_key);

  /* needed for old servers that can't shove data back into slink */
  send_queued_write(client_p);

  SetCryptOut(client_p);
  MyFree(b64_key);
}
示例#2
0
/*
 * mr_server - SERVER message handler
 *      parv[0] = sender prefix
 *      parv[1] = servername
 *      parv[2] = serverinfo/hopcount
 *      parv[3] = serverinfo
 */
static void mr_server(struct Client *client_p, struct Client *source_p,
                      int parc, char *parv[])
{
  char             info[REALLEN + 1];
  char             *name;
  struct Client    *target_p;
  int hop;

  if (parc < 4)
    {
      sendto_one(client_p,"ERROR :No servername");
      exit_client(client_p, client_p, client_p, "Wrong number of args");
      return;
    }

  name = parv[1];
  hop = atoi(parv[2]);
  strlcpy(info, parv[3], REALLEN);

  /* 
   * Reject a direct nonTS server connection if we're TS_ONLY -orabidoo
   */
  if (!DoesTS(client_p))
    {
      sendto_realops_flags(FLAGS_ALL, L_ADMIN,"Link %s dropped, non-TS server",
			   get_client_name(client_p, HIDE_IP));
      sendto_realops_flags(FLAGS_ALL, L_OPER,"Link %s dropped, non-TS server",
			   get_client_name(client_p, MASK_IP));
      exit_client(client_p, client_p, client_p, "Non-TS server");
      return;
    }

  if (bogus_host(name))
  {
    exit_client(client_p, client_p, client_p, "Bogus server name");
    return;
  }

  /* Now we just have to call check_server and everything should be
   * check for us... -A1kmm. */
  switch (check_server(name, client_p, CHECK_SERVER_NOCRYPTLINK))
  {
    case -1:
      if (ConfigFileEntry.warn_no_nline)
      {
        sendto_realops_flags(FLAGS_ALL, L_ADMIN,
           "Unauthorized server connection attempt from %s: No entry for "
           "servername %s", get_client_name(client_p, HIDE_IP), name);

        sendto_realops_flags(FLAGS_ALL, L_OPER,
           "Unauthorized server connection attempt from %s: No entry for "
           "servername %s", get_client_name(client_p, MASK_IP), name);
      }
      
      exit_client(client_p, client_p, client_p, "Invalid servername.");
      return;
      /* NOT REACHED */
      break;
      
    case -2:
      sendto_realops_flags(FLAGS_ALL, L_ADMIN,
           "Unauthorized server connection attempt from %s: Bad password "
           "for server %s", get_client_name(client_p, HIDE_IP), name);

      sendto_realops_flags(FLAGS_ALL, L_OPER,
           "Unauthorized server connection attempt from %s: Bad password "
           "for server %s", get_client_name(client_p, MASK_IP), name);

      exit_client(client_p, client_p, client_p, "Invalid password.");
      return;
      /* NOT REACHED */
      break;
      
    case -3:
      sendto_realops_flags(FLAGS_ALL, L_ADMIN,
           "Unauthorized server connection attempt from %s: Invalid host "
           "for server %s", get_client_name(client_p, HIDE_IP), name);

      sendto_realops_flags(FLAGS_ALL, L_OPER,
           "Unauthorized server connection attempt from %s: Invalid host "
           "for server %s", get_client_name(client_p, MASK_IP), name);

      exit_client(client_p, client_p, client_p, "Invalid host.");
      return;
      /* NOT REACHED */
      break;
    
    /* servername is > HOSTLEN */
    case -4:
      sendto_realops_flags(FLAGS_ALL, L_ADMIN,
                           "Invalid servername %s from %s",
			   name, get_client_name(client_p, HIDE_IP));
      sendto_realops_flags(FLAGS_ALL, L_OPER,
		           "Invalid servername %s from %s",
			   name, get_client_name(client_p, MASK_IP));

      exit_client(client_p, client_p, client_p, "Invalid servername.");
      return;
      /* NOT REACHED */
      break;
  }
    
  if ((target_p = server_exists(name)))
    {
      /*
       * This link is trying feed me a server that I already have
       * access through another path -- multiple paths not accepted
       * currently, kill this link immediately!!
       *
       * Rather than KILL the link which introduced it, KILL the
       * youngest of the two links. -avalon
       *
       * Definitely don't do that here. This is from an unregistered
       * connect - A1kmm.
       */
      sendto_realops_flags(FLAGS_ALL, L_ADMIN,
         "Attempt to re-introduce server %s from %s", name,
         get_client_name(client_p, HIDE_IP));

      sendto_realops_flags(FLAGS_ALL, L_OPER,
         "Attempt to re-introduce server %s from %s", name,
         get_client_name(client_p, MASK_IP));

      sendto_one(client_p, "ERROR :Server already exists.");
      exit_client(client_p, client_p, client_p, "Server Exists");
      return;
    }

  if(ServerInfo.hub && IsCapable(client_p, CAP_LL))
    {
      if(IsCapable(client_p, CAP_HUB))
        {
          ClearCap(client_p,CAP_LL);
          sendto_realops_flags(FLAGS_ALL, L_ALL,
               "*** LazyLinks to a hub from a hub, thats a no-no.");
        }
      else
        {
          client_p->localClient->serverMask = nextFreeMask();

          if(!client_p->localClient->serverMask)
            {
              sendto_realops_flags(FLAGS_ALL, L_ALL,
                                   "serverMask is full!");
              /* try and negotiate a non LL connect */
              ClearCap(client_p,CAP_LL);
            }
        }
    }
  else if (IsCapable(client_p, CAP_LL))
    {
      if(!IsCapable(client_p, CAP_HUB))
        {
          ClearCap(client_p,CAP_LL);
          sendto_realops_flags(FLAGS_ALL, L_ALL,
               "*** LazyLinks to a leaf from a leaf, thats a no-no.");
        }
    }

  /*
   * if we are connecting (Handshake), we already have the name from the
   * C:line in client_p->name
   */

  strlcpy(client_p->name, name, HOSTLEN+1);
  set_server_gecos(client_p, info);
  client_p->hopcount = hop;
  server_estab(client_p);
}