http_send.c

   1 /*
   2  * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
   3  *
   4  *     This program is free software; you can redistribute it and/or modify
   5  *     it under the terms of the GNU General Public License as published by
   6  *     the Free Software Foundation; either version 2 of the License, or
   7  *     (at your option) any later version.
   8  *
   9  *     This program is distributed in the hope that it will be useful,
  10  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *     GNU General Public License for more details.
  13  *
  14  *     You should have received a copy of the GNU General Public License
  15  *     along with this program; if not, write to the Free Software
  16  *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  17  */
  18
  19 /** \file http_send.c paraslash's http sender */
  20
  21
  22 #include "server.cmdline.h"
  23 #include "server.h"
  24 #include "http.h"
  25 #include "afs.h"
  26 #include "send.h"
  27 #include "list.h"
  28 #include "close_on_fork.h"
  29 #include "error.h"
  30 #include "net.h"
  31 #include "string.h"
  32 #include "fd.h"
  33
  34 /** \cond convert sock_addr_in to ascii */
  35 #define CLIENT_ADDR(hc) inet_ntoa((hc)->addr.sin_addr)
  36 /* get the port number of a struct http_client */
  37 #define CLIENT_PORT(hc) (hc)->addr.sin_port
  38 #define HTTP_ERR_MSG "HTTP/1.0 400 Bad Request\n"
  39 /** \endcond */
  40
  41 extern struct gengetopt_args_info conf;
  42
  43 /** the possible states of a client from the server's POV */
  44 enum http_status {
  45         HTTP_CONNECTED,
  46         HTTP_GOT_GET_REQUEST,
  47         HTTP_SENT_OK_MSG,
  48         HTTP_READY_TO_STREAM,
  49         HTTP_STREAMING,
  50         HTTP_INVALID_GET_REQUEST
  51 };
  52
  53 /** clients will be kicked if there are more than that many bytes pending */
  54 #define MAX_BACKLOG 40000
  55 /** the list of connected clients **/
  56 static struct list_head clients;
  57 /** the whitelist/blacklist */
  58 static struct list_head access_perm_list;
  59
  60 /** describes one client that connected the tcp port of the http sender */
  61 struct http_client {
  62 /** the file descriptor of the client */
  63         int fd;
  64 /** address information about the client */
  65         struct sockaddr_in addr;
  66 /** the client's current status */
  67         enum http_status status;
  68 /** non-zero if we included \a fd in the read set */
  69         int check_r;
  70 /** non-zero if we included \a fd in the write set */
  71         int check_w;
  72 /** the position of this client in the client list */
  73         struct list_head node;
  74 /** the list of pending packets for this client */
  75         struct list_head packet_queue;
  76 /** the number of pending bytes for this client */
  77         unsigned long pq_bytes;
  78 };
  79
  80 /**
  81  * describes one queued data packet for a client
  82  *
  83  * The send function of the http sender checks each client fd for writing. If a
  84  * client fd is not ready, it tries to queue that packet for this client until
  85  * the number of queued bytes exceeds \p MAX_BACKLOG.
  86  */
  87 struct queued_packet {
  88 /** the length of the packet in bytes */
  89         unsigned int len;
  90 /** pointer to the packet data */
  91         char *packet;
  92 /** position of the packet in the packet list */
  93         struct list_head node;
  94 };
  95
  96 /**
  97  * describes one entry in the blacklist/whitelist of the http sender
  98  */
  99 struct access_info {
 100         /** the address to be black/whitelisted */
 101         struct in_addr addr;
 102         /** the netmask for this entry */
 103         int netmask;
 104         /** the position of this entry in the access_perm_list */
 105         struct list_head node;
 106 };
 107
 108 static int server_fd = -1, numclients;
 109 static struct sender *self;
 110
 111
 112 static void http_shutdown_client(struct http_client *hc, const char *msg)
 113 {
 114         struct queued_packet *qp, *tmp;
 115         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", CLIENT_ADDR(hc),
 116                 hc->fd, msg);
 117         numclients--;
 118         close(hc->fd);
 119
 120         list_for_each_entry_safe(qp, tmp, &hc->packet_queue, node) {
 121                 free(qp->packet);
 122                 list_del(&qp->node);
 123                 free(qp);
 124         }
 125         list_del(&hc->node);
 126         free(hc);
 127 }
 128
 129 static void http_shutdown_clients_real(void)
 130 {
 131         struct http_client *hc, *tmp;
 132         list_for_each_entry_safe(hc, tmp, &clients, node)
 133                 http_shutdown_client(hc, "afs request");
 134 }
 135 static void http_shutdown_clients(void)
 136 {
 137         struct http_client *hc, *tmp;
 138         list_for_each_entry_safe(hc, tmp, &clients, node)
 139                 http_shutdown_client(hc, "afs request");
 140 }
 141
 142 static int http_send_msg(struct http_client *hc, const char *msg)
 143 {
 144         int ret = send_buffer(hc->fd, msg);
 145
 146         if (ret < 0)
 147                 http_shutdown_client(hc, "send msg failed");
 148         return ret;
 149 }
 150
 151 static void http_send_ok_msg(struct http_client *hc)
 152 {
 153         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 154         http_send_msg(hc, HTTP_OK_MSG);
 155 }
 156
 157 static int http_send_err_msg(struct http_client *hc)
 158 {
 159         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 160         return http_send_msg(hc, HTTP_ERR_MSG);
 161 }
 162
 163 static int queue_packet(struct http_client *hc, const char *buf, size_t len)
 164 {
 165         struct queued_packet *qp;
 166         if (hc->pq_bytes + len > MAX_BACKLOG) {
 167                 http_shutdown_client(hc, "packet queue overrun");
 168                 return -E_QUEUE;
 169         }
 170         qp = para_malloc(sizeof(struct queued_packet));
 171         hc->pq_bytes += len;
 172         qp->packet = para_malloc(len);
 173         memcpy(qp->packet, buf, len);
 174         qp->len = len;
 175         list_add_tail(&qp->node, &hc->packet_queue);
 176         PARA_INFO_LOG("%lu bytes queued for fd %d\n", hc->pq_bytes, hc->fd);
 177         return 1;
 178 }
 179
 180 static int send_queued_packets(struct http_client *hc)
 181 {
 182         int ret;
 183         struct queued_packet *qp, *tmp;
 184
 185         if (list_empty(&hc->packet_queue))
 186                 return 1;
 187         list_for_each_entry_safe(qp, tmp, &hc->packet_queue, node) {
 188                 ret = write_ok(hc->fd);
 189                 if (ret <= 0)
 190                         return ret? -E_WRITE_OK : 0;
 191                 ret = write(hc->fd, qp->packet, qp->len);
 192                 if (ret < 0)
 193                         return ret;
 194                 if (ret != qp->len) {
 195                         qp->len -= ret;
 196                         memmove(qp->packet, qp->packet + ret, qp->len);
 197                         return 0;
 198                 }
 199                 hc->pq_bytes -= qp->len;
 200                 free(qp->packet);
 201                 list_del(&qp->node);
 202                 free(qp);
 203         }
 204         return 1;
 205 }
 206
 207 static void http_send( long unsigned current_chunk,
 208         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 209 {
 210         struct http_client *hc, *tmp;
 211         int ret;
 212
 213         list_for_each_entry_safe(hc, tmp, &clients, node) {
 214                 if (hc->status != HTTP_STREAMING &&
 215                                 hc->status != HTTP_READY_TO_STREAM)
 216                         continue;
 217                 if (hc->status == HTTP_READY_TO_STREAM) {
 218                         int hlen;
 219                         char *buf = afs_get_header(&hlen);
 220                         if (buf && hlen > 0 && current_chunk) {
 221                                 /* need to send header */
 222                                 PARA_INFO_LOG("queueing header: %d\n", hlen);
 223                                 if (queue_packet(hc, buf, hlen) < 0)
 224                                         continue;
 225                         } else
 226                                 PARA_INFO_LOG("%s", "no need to queue header\n");
 227                         hc->status = HTTP_STREAMING;
 228                 }
 229                 ret = send_queued_packets(hc);
 230                 if (ret < 0) {
 231                         http_shutdown_client(hc, "send error");
 232                         continue;
 233                 }
 234                 if (!len)
 235                         continue;
 236                 if (!ret || write_ok(hc->fd) <= 0) {
 237                         PARA_INFO_LOG("fd %d not ready (%lu bytes queued),"
 238                                 " trying to queue packet\n", hc->fd,
 239                                 hc->pq_bytes);
 240                         queue_packet(hc, buf, len);
 241                         continue;
 242                 }
 243 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, CLIENT_ADDR(hc));
 244                 ret = write(hc->fd, buf, len);
 245                 if (ret < 0) {
 246                         http_shutdown_client(hc, "send error");
 247                         continue;
 248                 }
 249                 if (ret != len)
 250                         queue_packet(hc, buf + ret, len - ret);
 251         }
 252 }
 253
 254 static int host_in_access_perm_list(struct http_client *hc)
 255 {
 256         struct access_info *ai, *tmp;
 257         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 258                 unsigned mask = ((~0) >> ai->netmask);
 259                 if ((hc->addr.sin_addr.s_addr & mask) == (ai->addr.s_addr & mask))
 260                         return 1;
 261         }
 262         return 0;
 263 }
 264
 265 static void http_post_select(fd_set *rfds, fd_set *wfds)
 266 {
 267         int i = -1, match;
 268         struct http_client *hc, *tmp;
 269         const char *err_msg;
 270
 271         list_for_each_entry_safe(hc, tmp, &clients, node) {
 272                 i++;
 273 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, CLIENT_ADDR(hc));
 274                 switch (hc->status) {
 275                 case HTTP_STREAMING: /* nothing to do */
 276                 case HTTP_READY_TO_STREAM:
 277                         break;
 278                 case HTTP_CONNECTED: /* need to recv get request */
 279                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 280                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 281                                                 < 0) {
 282                                         hc->status = HTTP_INVALID_GET_REQUEST;
 283                                 } else {
 284                                         hc->status = HTTP_GOT_GET_REQUEST;
 285                                         PARA_INFO_LOG("%s",
 286                                                 "received get request\n");
 287                                 }
 288                         }
 289                         break;
 290                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 291                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 292                                 hc->status = HTTP_SENT_OK_MSG;
 293                                 http_send_ok_msg(hc);
 294                         }
 295                         break;
 296                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 297                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 298                                 if (http_send_err_msg(hc) >= 0)
 299                                         http_shutdown_client(hc,
 300                                                 "invalid get request");
 301                         }
 302                         break;
 303                 case HTTP_SENT_OK_MSG: /* need to send header? */
 304                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 305                                 hc->status = HTTP_READY_TO_STREAM;
 306                         break;
 307                 }
 308         }
 309         if (!FD_ISSET(server_fd, rfds))
 310                 return;
 311         hc = para_calloc(sizeof(struct http_client));
 312         err_msg = "accept error";
 313         hc->fd = para_accept(server_fd, &hc->addr, sizeof(struct sockaddr_in));
 314         if (hc->fd <= 0)
 315                 goto err_out;
 316         PARA_NOTICE_LOG("connection from %s (fd %d)\n", CLIENT_ADDR(hc), hc->fd);
 317         if (conf.http_max_clients_arg > 0 && numclients >=
 318                         conf.http_max_clients_arg) {
 319                 err_msg = "server full";
 320                 goto err_out;
 321         }
 322         match = host_in_access_perm_list(hc);
 323         PARA_DEBUG_LOG("host_in_access_perm_list: %d\n", match);
 324         if ((match && !conf.http_default_deny_given) ||
 325                         (!match && conf.http_default_deny_given)) {
 326                 err_msg = "permission denied";
 327                 goto err_out;
 328         }
 329         hc->status = HTTP_CONNECTED;
 330         INIT_LIST_HEAD(&hc->packet_queue);
 331         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 332                 CLIENT_ADDR(hc), hc->fd);
 333         numclients++;
 334         list_add(&hc->node, &clients);
 335         return;
 336 err_out:
 337         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 338                 CLIENT_ADDR(hc), err_msg);
 339         if (hc->fd > 0)
 340                 close(hc->fd);
 341         free(hc);
 342 }
 343
 344 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 345 {
 346         struct http_client *hc, *tmp;
 347
 348         if (server_fd < 0)
 349                 return;
 350         para_fd_set(server_fd, rfds, max_fileno);
 351         list_for_each_entry_safe(hc, tmp, &clients, node) {
 352                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 353                 hc->check_r = 0;
 354                 hc->check_w = 0;
 355                 switch (hc->status) {
 356                 case HTTP_STREAMING:
 357                 case HTTP_READY_TO_STREAM:
 358                         break;
 359                 case HTTP_CONNECTED: /* need to recv get request */
 360                         para_fd_set(hc->fd, rfds, max_fileno);
 361                         hc->check_r = 1;
 362                         break;
 363                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 364                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 365                         para_fd_set(hc->fd, wfds, max_fileno);
 366                         hc->check_w = 1;
 367                         break;
 368                 case HTTP_SENT_OK_MSG:
 369                         if (!afs_playing())
 370                                 break; /* wait until server starts playing */
 371                         para_fd_set(hc->fd, wfds, max_fileno);
 372                         hc->check_w = 1;
 373                         break;
 374                 }
 375         }
 376 }
 377
 378 static int open_tcp_port(int port)
 379 {
 380         server_fd = init_tcp_socket(port);
 381         if (server_fd < 0) {
 382                 http_shutdown_clients_real();
 383                 self->status = SENDER_OFF;
 384                 return server_fd;
 385         }
 386         self->status = SENDER_ON;
 387         add_close_on_fork_list(server_fd);
 388         return 1;
 389 }
 390
 391 static int http_com_on(__a_unused struct sender_command_data *scd)
 392 {
 393         if (self->status == SENDER_ON)
 394                 return 1;
 395         return open_tcp_port(conf.http_port_arg);
 396 }
 397
 398 static int http_com_off(__a_unused struct sender_command_data *scd)
 399 {
 400         self->status = SENDER_OFF;
 401         if (server_fd > 0) {
 402                 close(server_fd);
 403                 del_close_on_fork_list(server_fd);
 404                 server_fd = -1;
 405         }
 406         http_shutdown_clients_real();
 407         return 1;
 408 }
 409
 410 static void del_perm_list_entry(struct sender_command_data *scd)
 411 {
 412         struct access_info *ai, *tmp;
 413
 414         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 415                 char *nad = para_strdup(inet_ntoa(ai->addr));
 416                 if (!strcmp(nad, inet_ntoa(scd->addr)) &&
 417                                 ai->netmask == scd->netmask) {
 418                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 419                                 nad, ai->netmask);
 420                         list_del(&ai->node);
 421                         free(ai);
 422                 }
 423                 free(nad);
 424         }
 425 }
 426
 427 static void add_perm_list_entry(struct sender_command_data *scd)
 428 {
 429         struct access_info *ai = para_malloc(sizeof(struct access_info));
 430         ai->addr = scd->addr;
 431         ai->netmask = scd->netmask;
 432         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 433                 ai->netmask);
 434         list_add(&ai->node, &access_perm_list);
 435 }
 436
 437 static int http_com_deny(struct sender_command_data *scd)
 438 {
 439         if (conf.http_default_deny_given)
 440                 del_perm_list_entry(scd);
 441         else
 442                 add_perm_list_entry(scd);
 443         return 1;
 444 }
 445
 446 static int http_com_allow(struct sender_command_data *scd)
 447 {
 448         if (conf.http_default_deny_given)
 449                 add_perm_list_entry(scd);
 450         else
 451                 del_perm_list_entry(scd);
 452         return 1;
 453 }
 454
 455 static char *http_info(void)
 456 {
 457         char *clnts = NULL, *ap = NULL, *ret;
 458         struct access_info *ai, *tmp_ai;
 459         struct http_client *hc, *tmp_hc;
 460
 461         list_for_each_entry_safe(ai, tmp_ai, &access_perm_list, node) {
 462                 char *tmp = make_message("%s%s/%d ", ap? ap : "",
 463                         inet_ntoa(ai->addr), ai->netmask);
 464                 free(ap);
 465                 ap = tmp;
 466         }
 467         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 468                 char *tmp = make_message("%s%s:%d ", clnts? clnts : "",
 469                         CLIENT_ADDR(hc), CLIENT_PORT(hc));
 470                 free(clnts);
 471                 clnts = tmp;
 472         }
 473         ret = make_message(
 474                 "http status: %s\n"
 475                 "http tcp port: %d\n"
 476                 "http clients: %d\n"
 477                 "http maximal number of clients: %d%s\n"
 478                 "http connected clients: %s\n"
 479                 "http access %s list: %s\n",
 480                 (self->status == SENDER_ON)? "on" : "off",
 481                 conf.http_port_arg,
 482                 numclients,
 483                 conf.http_max_clients_arg,
 484                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 485                 clnts? clnts : "(none)",
 486                 conf.http_default_deny_given? "allow" : "deny",
 487                 ap? ap : "(none)"
 488         );
 489         free(ap);
 490         free(clnts);
 491         return ret;
 492 }
 493
 494 static void init_access_control_list(void)
 495 {
 496         int i;
 497         struct sender_command_data scd;
 498
 499         INIT_LIST_HEAD(&access_perm_list);
 500         for (i = 0; i < conf.http_access_given; i++) {
 501                 char *arg = para_strdup(conf.http_access_arg[i]);
 502                 char *p = strchr(arg, '/');
 503                 if (!p)
 504                         goto err;
 505                 *p = '\0';
 506                 if (!inet_aton(arg, &scd.addr))
 507                         goto err;
 508                 scd.netmask = atoi(++p);
 509                 if (scd.netmask < 0 || scd.netmask > 32)
 510                         goto err;
 511                 add_perm_list_entry(&scd);
 512                 goto success;
 513 err:
 514                 PARA_CRIT_LOG("syntax error for http_access option "
 515                         "#%d, ignoring\n", i);
 516 success:
 517                 free(arg);
 518                 continue;
 519         }
 520 }
 521
 522 static char *http_help(void)
 523 {
 524         return make_message(
 525                 "usage: {on|off}\n"
 526                 "usage: {allow|deny} IP mask\n"
 527                 "example: allow 127.0.0.1 32\n"
 528         );
 529 }
 530
 531 /**
 532  * the init function of the http sender
 533  *
 534  * \param s pointer to the http sender struct
 535  *
 536  * It initializes all function pointers of \a s, init the client list and the
 537  * acess control list as well. If autostart is wanted, open the tcp port.
 538  */
 539 void http_send_init(struct sender *s)
 540 {
 541         INIT_LIST_HEAD(&clients);
 542         s->info = http_info;
 543         s->send = http_send;
 544         s->pre_select = http_pre_select;
 545         s->post_select = http_post_select;
 546         s->shutdown_clients = http_shutdown_clients;
 547         s->help = http_help;
 548         s->client_cmds[SENDER_ON] = http_com_on;
 549         s->client_cmds[SENDER_OFF] = http_com_off;
 550         s->client_cmds[SENDER_DENY] = http_com_deny;
 551         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 552         s->client_cmds[SENDER_ADD] = NULL;
 553         s->client_cmds[SENDER_DELETE] = NULL;
 554         self = s;
 555         init_access_control_list();
 556         if (!conf.http_no_autostart_given)
 557                 open_tcp_port(conf.http_port_arg); /* ignore errors */
 558         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 559 }