http_send.c

   1 /*
   2  * Copyright (C) 2005-2007 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file http_send.c paraslash's http sender */
   8
   9
  10 #include "server.cmdline.h"
  11 #include "server.h"
  12 #include "http.h"
  13 #include "vss.h"
  14 #include "send.h"
  15 #include "list.h"
  16 #include "close_on_fork.h"
  17 #include "error.h"
  18 #include "net.h"
  19 #include "string.h"
  20 #include "fd.h"
  21
  22 /** \cond convert sock_addr_in to ascii */
  23 #define CLIENT_ADDR(hc) inet_ntoa((hc)->addr.sin_addr)
  24 /* get the port number of a struct http_client */
  25 #define CLIENT_PORT(hc) (hc)->addr.sin_port
  26 #define HTTP_ERR_MSG "HTTP/1.0 400 Bad Request\n"
  27 /** \endcond */
  28
  29 /** the possible states of a client from the server's POV */
  30 enum http_status {
  31         HTTP_CONNECTED,
  32         HTTP_GOT_GET_REQUEST,
  33         HTTP_SENT_OK_MSG,
  34         HTTP_READY_TO_STREAM,
  35         HTTP_STREAMING,
  36         HTTP_INVALID_GET_REQUEST
  37 };
  38
  39 /** clients will be kicked if there are more than that many bytes pending */
  40 #define MAX_BACKLOG 40000
  41 /** the list of connected clients **/
  42 static struct list_head clients;
  43 /** the whitelist/blacklist */
  44 static struct list_head access_perm_list;
  45
  46 /** describes one client that connected the tcp port of the http sender */
  47 struct http_client {
  48 /** the file descriptor of the client */
  49         int fd;
  50 /** address information about the client */
  51         struct sockaddr_in addr;
  52 /** the client's current status */
  53         enum http_status status;
  54 /** non-zero if we included \a fd in the read set */
  55         int check_r;
  56 /** non-zero if we included \a fd in the write set */
  57         int check_w;
  58 /** the position of this client in the client list */
  59         struct list_head node;
  60 /** the list of pending packets for this client */
  61         struct list_head packet_queue;
  62 /** the number of pending bytes for this client */
  63         unsigned long pq_bytes;
  64 };
  65
  66 /**
  67  * describes one queued data packet for a client
  68  *
  69  * The send function of the http sender checks each client fd for writing. If a
  70  * client fd is not ready, it tries to queue that packet for this client until
  71  * the number of queued bytes exceeds \p MAX_BACKLOG.
  72  */
  73 struct queued_packet {
  74 /** the length of the packet in bytes */
  75         unsigned int len;
  76 /** pointer to the packet data */
  77         char *packet;
  78 /** position of the packet in the packet list */
  79         struct list_head node;
  80 };
  81
  82 /**
  83  * describes one entry in the blacklist/whitelist of the http sender
  84  */
  85 struct access_info {
  86         /** the address to be black/whitelisted */
  87         struct in_addr addr;
  88         /** the netmask for this entry */
  89         unsigned netmask;
  90         /** the position of this entry in the access_perm_list */
  91         struct list_head node;
  92 };
  93
  94 static int server_fd = -1, numclients;
  95 static struct sender *self;
  96
  97
  98 static void http_shutdown_client(struct http_client *hc, const char *msg)
  99 {
 100         struct queued_packet *qp, *tmp;
 101         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", CLIENT_ADDR(hc),
 102                 hc->fd, msg);
 103         numclients--;
 104         close(hc->fd);
 105         del_close_on_fork_list(hc->fd);
 106         list_for_each_entry_safe(qp, tmp, &hc->packet_queue, node) {
 107                 free(qp->packet);
 108                 list_del(&qp->node);
 109                 free(qp);
 110         }
 111         list_del(&hc->node);
 112         free(hc);
 113 }
 114
 115 static void http_shutdown_clients(void)
 116 {
 117         struct http_client *hc, *tmp;
 118         list_for_each_entry_safe(hc, tmp, &clients, node)
 119                 http_shutdown_client(hc, "vss request");
 120 }
 121
 122 static int http_send_msg(struct http_client *hc, const char *msg)
 123 {
 124         int ret = send_buffer(hc->fd, msg);
 125
 126         if (ret < 0)
 127                 http_shutdown_client(hc, "send msg failed");
 128         return ret;
 129 }
 130
 131 static void http_send_ok_msg(struct http_client *hc)
 132 {
 133         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 134         http_send_msg(hc, HTTP_OK_MSG);
 135 }
 136
 137 static int http_send_err_msg(struct http_client *hc)
 138 {
 139         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 140         return http_send_msg(hc, HTTP_ERR_MSG);
 141 }
 142
 143 static int queue_packet(struct http_client *hc, const char *buf, size_t len)
 144 {
 145         struct queued_packet *qp;
 146         if (hc->pq_bytes + len > MAX_BACKLOG) {
 147                 http_shutdown_client(hc, "packet queue overrun");
 148                 return -E_QUEUE;
 149         }
 150         qp = para_malloc(sizeof(struct queued_packet));
 151         hc->pq_bytes += len;
 152         qp->packet = para_malloc(len);
 153         memcpy(qp->packet, buf, len);
 154         qp->len = len;
 155         list_add_tail(&qp->node, &hc->packet_queue);
 156         PARA_INFO_LOG("%lu bytes queued for fd %d\n", hc->pq_bytes, hc->fd);
 157         return 1;
 158 }
 159
 160 static int send_queued_packets(struct http_client *hc)
 161 {
 162         int ret;
 163         struct queued_packet *qp, *tmp;
 164
 165         if (list_empty(&hc->packet_queue))
 166                 return 1;
 167         list_for_each_entry_safe(qp, tmp, &hc->packet_queue, node) {
 168                 ret = write_ok(hc->fd);
 169                 if (ret <= 0)
 170                         return ret? -E_WRITE_OK : 0;
 171                 ret = write(hc->fd, qp->packet, qp->len);
 172                 if (ret < 0)
 173                         return ret;
 174                 if (ret != qp->len) {
 175                         qp->len -= ret;
 176                         memmove(qp->packet, qp->packet + ret, qp->len);
 177                         return 0;
 178                 }
 179                 hc->pq_bytes -= qp->len;
 180                 free(qp->packet);
 181                 list_del(&qp->node);
 182                 free(qp);
 183         }
 184         return 1;
 185 }
 186
 187 static void http_send( long unsigned current_chunk,
 188         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 189 {
 190         struct http_client *hc, *tmp;
 191         int ret;
 192
 193         list_for_each_entry_safe(hc, tmp, &clients, node) {
 194                 if (hc->status != HTTP_STREAMING &&
 195                                 hc->status != HTTP_READY_TO_STREAM)
 196                         continue;
 197                 if (hc->status == HTTP_READY_TO_STREAM) {
 198                         unsigned hlen;
 199                         char *hbuf = vss_get_header(&hlen);
 200                         if (hbuf && hlen > 0 && current_chunk) {
 201                                 /* need to send header */
 202                                 PARA_INFO_LOG("queueing header: %d\n", hlen);
 203                                 if (queue_packet(hc, hbuf, hlen) < 0)
 204                                         continue;
 205                         } else
 206                                 PARA_INFO_LOG("%s", "no need to queue header\n");
 207                         hc->status = HTTP_STREAMING;
 208                 }
 209                 ret = send_queued_packets(hc);
 210                 if (ret < 0) {
 211                         http_shutdown_client(hc, "send error");
 212                         continue;
 213                 }
 214                 if (!len)
 215                         continue;
 216                 if (!ret || write_ok(hc->fd) <= 0) {
 217                         PARA_INFO_LOG("fd %d not ready (%lu bytes queued),"
 218                                 " trying to queue packet\n", hc->fd,
 219                                 hc->pq_bytes);
 220                         queue_packet(hc, buf, len);
 221                         continue;
 222                 }
 223 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, CLIENT_ADDR(hc));
 224                 ret = write(hc->fd, buf, len);
 225                 if (ret < 0) {
 226                         http_shutdown_client(hc, "send error");
 227                         continue;
 228                 }
 229                 if (ret != len)
 230                         queue_packet(hc, buf + ret, len - ret);
 231         }
 232 }
 233
 234 static int host_in_access_perm_list(struct http_client *hc)
 235 {
 236         struct access_info *ai, *tmp;
 237         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 238                 unsigned mask = ((~0U) >> ai->netmask);
 239                 if ((hc->addr.sin_addr.s_addr & mask) == (ai->addr.s_addr & mask))
 240                         return 1;
 241         }
 242         return 0;
 243 }
 244
 245 static void http_post_select(fd_set *rfds, fd_set *wfds)
 246 {
 247         int i = -1, match;
 248         struct http_client *hc, *tmp;
 249         const char *err_msg;
 250
 251         list_for_each_entry_safe(hc, tmp, &clients, node) {
 252                 i++;
 253 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, CLIENT_ADDR(hc));
 254                 switch (hc->status) {
 255                 case HTTP_STREAMING: /* nothing to do */
 256                 case HTTP_READY_TO_STREAM:
 257                         break;
 258                 case HTTP_CONNECTED: /* need to recv get request */
 259                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 260                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 261                                                 < 0) {
 262                                         hc->status = HTTP_INVALID_GET_REQUEST;
 263                                 } else {
 264                                         hc->status = HTTP_GOT_GET_REQUEST;
 265                                         PARA_INFO_LOG("%s",
 266                                                 "received get request\n");
 267                                 }
 268                         }
 269                         break;
 270                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 271                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 272                                 hc->status = HTTP_SENT_OK_MSG;
 273                                 http_send_ok_msg(hc);
 274                         }
 275                         break;
 276                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 277                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 278                                 if (http_send_err_msg(hc) >= 0)
 279                                         http_shutdown_client(hc,
 280                                                 "invalid get request");
 281                         }
 282                         break;
 283                 case HTTP_SENT_OK_MSG: /* need to send header? */
 284                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 285                                 hc->status = HTTP_READY_TO_STREAM;
 286                         break;
 287                 }
 288         }
 289         if (!FD_ISSET(server_fd, rfds))
 290                 return;
 291         hc = para_calloc(sizeof(struct http_client));
 292         err_msg = "accept error";
 293         hc->fd = para_accept(server_fd, &hc->addr, sizeof(struct sockaddr_in));
 294         if (hc->fd <= 0)
 295                 goto err_out;
 296         PARA_NOTICE_LOG("connection from %s (fd %d)\n", CLIENT_ADDR(hc), hc->fd);
 297         if (conf.http_max_clients_arg > 0 && numclients >=
 298                         conf.http_max_clients_arg) {
 299                 err_msg = "server full";
 300                 goto err_out;
 301         }
 302         match = host_in_access_perm_list(hc);
 303         PARA_DEBUG_LOG("host_in_access_perm_list: %d\n", match);
 304         if ((match && !conf.http_default_deny_given) ||
 305                         (!match && conf.http_default_deny_given)) {
 306                 err_msg = "permission denied";
 307                 goto err_out;
 308         }
 309         hc->status = HTTP_CONNECTED;
 310         INIT_LIST_HEAD(&hc->packet_queue);
 311         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 312                 CLIENT_ADDR(hc), hc->fd);
 313         numclients++;
 314         para_list_add(&hc->node, &clients);
 315         add_close_on_fork_list(hc->fd);
 316         mark_fd_nonblock(hc->fd);
 317         return;
 318 err_out:
 319         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 320                 CLIENT_ADDR(hc), err_msg);
 321         if (hc->fd > 0)
 322                 close(hc->fd);
 323         free(hc);
 324 }
 325
 326 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 327 {
 328         struct http_client *hc, *tmp;
 329
 330         if (server_fd < 0)
 331                 return;
 332         para_fd_set(server_fd, rfds, max_fileno);
 333         list_for_each_entry_safe(hc, tmp, &clients, node) {
 334                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 335                 hc->check_r = 0;
 336                 hc->check_w = 0;
 337                 switch (hc->status) {
 338                 case HTTP_STREAMING:
 339                 case HTTP_READY_TO_STREAM:
 340                         break;
 341                 case HTTP_CONNECTED: /* need to recv get request */
 342                         para_fd_set(hc->fd, rfds, max_fileno);
 343                         hc->check_r = 1;
 344                         break;
 345                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 346                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 347                         para_fd_set(hc->fd, wfds, max_fileno);
 348                         hc->check_w = 1;
 349                         break;
 350                 case HTTP_SENT_OK_MSG:
 351                         if (!vss_playing())
 352                                 break; /* wait until server starts playing */
 353                         para_fd_set(hc->fd, wfds, max_fileno);
 354                         hc->check_w = 1;
 355                         break;
 356                 }
 357         }
 358 }
 359
 360 static int open_tcp_port(int port)
 361 {
 362         int ret;
 363
 364         server_fd = init_tcp_socket(port);
 365         if (server_fd < 0) {
 366                 http_shutdown_clients();
 367                 self->status = SENDER_OFF;
 368                 return server_fd;
 369         }
 370         ret = mark_fd_nonblock(server_fd);
 371         if (ret < 0) {
 372                 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
 373                 exit(EXIT_FAILURE);
 374         }
 375         self->status = SENDER_ON;
 376         add_close_on_fork_list(server_fd);
 377         return 1;
 378 }
 379
 380 static int http_com_on(__a_unused struct sender_command_data *scd)
 381 {
 382         if (self->status == SENDER_ON)
 383                 return 1;
 384         return open_tcp_port(conf.http_port_arg);
 385 }
 386
 387 static int http_com_off(__a_unused struct sender_command_data *scd)
 388 {
 389         self->status = SENDER_OFF;
 390         if (server_fd > 0) {
 391                 close(server_fd);
 392                 del_close_on_fork_list(server_fd);
 393                 server_fd = -1;
 394         }
 395         http_shutdown_clients();
 396         return 1;
 397 }
 398
 399 static void del_perm_list_entry(struct sender_command_data *scd)
 400 {
 401         struct access_info *ai, *tmp;
 402
 403         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 404                 char *nad = para_strdup(inet_ntoa(ai->addr));
 405                 if (!strcmp(nad, inet_ntoa(scd->addr)) &&
 406                                 ai->netmask == scd->netmask) {
 407                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 408                                 nad, ai->netmask);
 409                         list_del(&ai->node);
 410                         free(ai);
 411                 }
 412                 free(nad);
 413         }
 414 }
 415
 416 static void add_perm_list_entry(struct sender_command_data *scd)
 417 {
 418         struct access_info *ai = para_malloc(sizeof(struct access_info));
 419         ai->addr = scd->addr;
 420         ai->netmask = scd->netmask;
 421         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 422                 ai->netmask);
 423         para_list_add(&ai->node, &access_perm_list);
 424 }
 425
 426 static int http_com_deny(struct sender_command_data *scd)
 427 {
 428         if (conf.http_default_deny_given)
 429                 del_perm_list_entry(scd);
 430         else
 431                 add_perm_list_entry(scd);
 432         return 1;
 433 }
 434
 435 static int http_com_allow(struct sender_command_data *scd)
 436 {
 437         if (conf.http_default_deny_given)
 438                 add_perm_list_entry(scd);
 439         else
 440                 del_perm_list_entry(scd);
 441         return 1;
 442 }
 443
 444 static char *http_info(void)
 445 {
 446         char *clnts = NULL, *ap = NULL, *ret;
 447         struct access_info *ai, *tmp_ai;
 448         struct http_client *hc, *tmp_hc;
 449
 450         list_for_each_entry_safe(ai, tmp_ai, &access_perm_list, node) {
 451                 char *tmp = make_message("%s%s/%d ", ap? ap : "",
 452                         inet_ntoa(ai->addr), ai->netmask);
 453                 free(ap);
 454                 ap = tmp;
 455         }
 456         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 457                 char *tmp = make_message("%s%s:%d ", clnts? clnts : "",
 458                         CLIENT_ADDR(hc), CLIENT_PORT(hc));
 459                 free(clnts);
 460                 clnts = tmp;
 461         }
 462         ret = make_message(
 463                 "http status: %s\n"
 464                 "http tcp port: %d\n"
 465                 "http clients: %d\n"
 466                 "http maximal number of clients: %d%s\n"
 467                 "http connected clients: %s\n"
 468                 "http access %s list: %s\n",
 469                 (self->status == SENDER_ON)? "on" : "off",
 470                 conf.http_port_arg,
 471                 numclients,
 472                 conf.http_max_clients_arg,
 473                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 474                 clnts? clnts : "(none)",
 475                 conf.http_default_deny_given? "allow" : "deny",
 476                 ap? ap : "(none)"
 477         );
 478         free(ap);
 479         free(clnts);
 480         return ret;
 481 }
 482
 483 static void init_access_control_list(void)
 484 {
 485         int i;
 486         struct sender_command_data scd;
 487
 488         INIT_LIST_HEAD(&access_perm_list);
 489         for (i = 0; i < conf.http_access_given; i++) {
 490                 char *arg = para_strdup(conf.http_access_arg[i]);
 491                 char *p = strchr(arg, '/');
 492                 if (!p)
 493                         goto err;
 494                 *p = '\0';
 495                 if (!inet_aton(arg, &scd.addr))
 496                         goto err;
 497                 scd.netmask = atoi(++p);
 498                 if (scd.netmask < 0 || scd.netmask > 32)
 499                         goto err;
 500                 add_perm_list_entry(&scd);
 501                 goto success;
 502 err:
 503                 PARA_CRIT_LOG("syntax error for http_access option "
 504                         "#%d, ignoring\n", i);
 505 success:
 506                 free(arg);
 507                 continue;
 508         }
 509 }
 510
 511 static char *http_help(void)
 512 {
 513         return make_message(
 514                 "usage: {on|off}\n"
 515                 "usage: {allow|deny} IP mask\n"
 516                 "example: allow 127.0.0.1 32\n"
 517         );
 518 }
 519
 520 /**
 521  * the init function of the http sender
 522  *
 523  * \param s pointer to the http sender struct
 524  *
 525  * It initializes all function pointers of \a s, init the client list and the
 526  * acess control list as well. If autostart is wanted, open the tcp port.
 527  */
 528 void http_send_init(struct sender *s)
 529 {
 530         INIT_LIST_HEAD(&clients);
 531         s->info = http_info;
 532         s->send = http_send;
 533         s->pre_select = http_pre_select;
 534         s->post_select = http_post_select;
 535         s->shutdown_clients = http_shutdown_clients;
 536         s->help = http_help;
 537         s->client_cmds[SENDER_ON] = http_com_on;
 538         s->client_cmds[SENDER_OFF] = http_com_off;
 539         s->client_cmds[SENDER_DENY] = http_com_deny;
 540         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 541         s->client_cmds[SENDER_ADD] = NULL;
 542         s->client_cmds[SENDER_DELETE] = NULL;
 543         self = s;
 544         init_access_control_list();
 545         if (!conf.http_no_autostart_given)
 546                 open_tcp_port(conf.http_port_arg); /* ignore errors */
 547         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 548 }