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         /** We accepted the connection on the tcp socket. */
  32         HTTP_CONNECTED,
  33         /** Successfully received the get request. */
  34         HTTP_GOT_GET_REQUEST,
  35         /** We sent the OK message back to the client. */
  36         HTTP_SENT_OK_MSG,
  37         /** Connection established, we might need to send the audio file header. */
  38         HTTP_READY_TO_STREAM,
  39         /** Connection is ready for sending audio data. */
  40         HTTP_STREAMING,
  41         /** We didn't receive a valid get request. */
  42         HTTP_INVALID_GET_REQUEST
  43 };
  44
  45 /** Clients will be kicked if there are more than that many bytes pending. */
  46 #define MAX_BACKLOG 40000
  47 /** The list of connected clients. */
  48 static struct list_head clients;
  49 /** The whitelist/blacklist. */
  50 static struct list_head access_perm_list;
  51
  52 /** Describes one client that connected the tcp port of the http sender. */
  53 struct http_client {
  54         /** The file descriptor of the client. */
  55         int fd;
  56         /** Address information about the client. */
  57         struct sockaddr_in addr;
  58         /** The client's current status. */
  59         enum http_status status;
  60         /** Non-zero if we included \a fd in the read set.*/
  61         int check_r;
  62         /** Non-zero if we included \a fd in the write set. */
  63         int check_w;
  64         /** The position of this client in the client list. */
  65         struct list_head node;
  66         /** The list of pending chunks for this client. */
  67         struct list_head chunk_queue;
  68         /** The number of pending bytes for this client. */
  69         unsigned long cq_bytes;
  70 };
  71
  72 /**
  73  * Describes one queued chunk of the chunk queue.
  74  *
  75  * The send function of the http sender checks each client fd for writing. If a
  76  * client fd is not ready, it tries to queue that chunk for this client until
  77  * the number of queued bytes exceeds \p MAX_BACKLOG.
  78  */
  79 struct queued_chunk {
  80         /** The number of the queued chunk, -1U means header. */
  81         unsigned chunk_num;
  82         /** The number of bytes already sent. */
  83         unsigned sent;
  84         /** Position of the chunk in the chunk queue. */
  85         struct list_head node;
  86 };
  87
  88 /**
  89  * Describes one entry in the blacklist/whitelist of the http sender.
  90  */
  91 struct access_info {
  92         /** The address to be black/whitelisted. */
  93         struct in_addr addr;
  94         /** The netmask for this entry. */
  95         unsigned netmask;
  96         /** The position of this entry in the access_perm_list. */
  97         struct list_head node;
  98 };
  99
 100 static int server_fd = -1, numclients;
 101 static struct sender *self;
 102
 103 static void http_shutdown_client(struct http_client *hc, const char *msg)
 104 {
 105         struct queued_chunk *qc, *tmp;
 106         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", CLIENT_ADDR(hc),
 107                 hc->fd, msg);
 108         numclients--;
 109         close(hc->fd);
 110         del_close_on_fork_list(hc->fd);
 111         list_for_each_entry_safe(qc, tmp, &hc->chunk_queue, node) {
 112                 list_del(&qc->node);
 113                 free(qc);
 114         }
 115         list_del(&hc->node);
 116         free(hc);
 117 }
 118
 119 static void http_shutdown_clients(void)
 120 {
 121         struct http_client *hc, *tmp;
 122         list_for_each_entry_safe(hc, tmp, &clients, node)
 123                 http_shutdown_client(hc, "vss request");
 124 }
 125
 126 static int http_send_msg(struct http_client *hc, const char *msg)
 127 {
 128         int ret = send_buffer(hc->fd, msg);
 129
 130         if (ret < 0)
 131                 http_shutdown_client(hc, "send msg failed");
 132         return ret;
 133 }
 134
 135 static void http_send_ok_msg(struct http_client *hc)
 136 {
 137         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 138         http_send_msg(hc, HTTP_OK_MSG);
 139 }
 140
 141 static int http_send_err_msg(struct http_client *hc)
 142 {
 143         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 144         return http_send_msg(hc, HTTP_ERR_MSG);
 145 }
 146
 147 static int queue_chunk(struct http_client *hc, long unsigned chunk_num,
 148         size_t sent)
 149 {
 150         struct queued_chunk *qc;
 151         char *buf;
 152         size_t len;
 153         int ret;
 154
 155         if (chunk_num != -1U) {
 156                 ret = vss_get_chunk(chunk_num, &buf, &len);
 157                 if (ret < 0)
 158                         return ret;
 159         } else
 160                 buf = vss_get_header(&len);
 161         if (hc->cq_bytes + len > MAX_BACKLOG)
 162                 return -E_QUEUE;
 163         qc = para_malloc(sizeof(struct queued_chunk));
 164         hc->cq_bytes += len;
 165         qc->chunk_num = chunk_num;
 166         qc->sent = sent;
 167         list_add_tail(&qc->node, &hc->chunk_queue);
 168         PARA_INFO_LOG("%lu bytes queued for fd %d\n", hc->cq_bytes, hc->fd);
 169         return 1;
 170 }
 171
 172 static int send_queued_chunks(struct http_client *hc)
 173 {
 174         int ret;
 175         struct queued_chunk *qc, *tmp;
 176
 177         if (list_empty(&hc->chunk_queue))
 178                 return 1;
 179         list_for_each_entry_safe(qc, tmp, &hc->chunk_queue, node) {
 180                 char *buf;
 181                 size_t len;
 182                 ret = write_ok(hc->fd);
 183                 if (ret <= 0)
 184                         return ret? -E_WRITE_OK : 0;
 185                 if (qc->chunk_num != -1U) {
 186                         ret = vss_get_chunk(qc->chunk_num, &buf, &len);
 187                         if (ret < 0)
 188                                 return ret;
 189                 } else
 190                         buf = vss_get_header(&len);
 191                 assert(len && len > qc->sent);
 192                 ret = write(hc->fd, buf + qc->sent, len - qc->sent);
 193                 if (ret < 0)
 194                         return -1; /* FIXME */
 195                 hc->cq_bytes -= ret;
 196                 if (ret != len - qc->sent) {
 197                         qc->sent += ret;
 198                         return 0;
 199                 }
 200                 list_del(&qc->node);
 201                 free(qc);
 202         }
 203         return 1;
 204 }
 205
 206 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 207         size_t sent)
 208 {
 209         int ret = queue_chunk(hc, chunk_num, sent);
 210         if (ret < 0)
 211                 http_shutdown_client(hc, "queue error");
 212         return ret;
 213 }
 214
 215 static void http_send( long unsigned current_chunk,
 216         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 217 {
 218         struct http_client *hc, *tmp;
 219         int ret;
 220
 221         list_for_each_entry_safe(hc, tmp, &clients, node) {
 222                 if (hc->status != HTTP_STREAMING &&
 223                                 hc->status != HTTP_READY_TO_STREAM)
 224                         continue;
 225                 if (hc->status == HTTP_READY_TO_STREAM) {
 226                         unsigned hlen;
 227                         char *hbuf = vss_get_header(&hlen);
 228                         if (hbuf && hlen > 0 && current_chunk) {
 229                                 /* need to send header */
 230                                 PARA_INFO_LOG("queueing header: %d\n", hlen);
 231                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 232                                         continue;
 233                         } else
 234                                 PARA_INFO_LOG("no need to queue header\n");
 235                         hc->status = HTTP_STREAMING;
 236                 }
 237                 ret = send_queued_chunks(hc);
 238                 if (ret < 0) {
 239                         http_shutdown_client(hc, "queue send error");
 240                         continue;
 241                 }
 242                 if (!len)
 243                         continue;
 244                 if (!ret || write_ok(hc->fd) <= 0) {
 245                         PARA_INFO_LOG("fd %d not ready (%lu bytes queued),"
 246                                 " trying to queue chunk\n", hc->fd,
 247                                 hc->cq_bytes);
 248                         queue_chunk_or_shutdown(hc, current_chunk, 0);
 249                         continue;
 250                 }
 251 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, CLIENT_ADDR(hc));
 252                 ret = write(hc->fd, buf, len);
 253 //              PARA_DEBUG_LOG("ret: %d\n", ret);
 254                 if (ret < 0) {
 255                         http_shutdown_client(hc, "send error");
 256                         continue;
 257                 }
 258                 if (ret != len)
 259                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 260         }
 261 }
 262
 263 static int host_in_access_perm_list(struct http_client *hc)
 264 {
 265         struct access_info *ai, *tmp;
 266         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 267                 unsigned mask = ((~0U) >> ai->netmask);
 268                 if ((hc->addr.sin_addr.s_addr & mask) == (ai->addr.s_addr & mask))
 269                         return 1;
 270         }
 271         return 0;
 272 }
 273
 274 static void http_post_select(fd_set *rfds, fd_set *wfds)
 275 {
 276         int i = -1, match;
 277         struct http_client *hc, *tmp;
 278         const char *err_msg;
 279
 280         list_for_each_entry_safe(hc, tmp, &clients, node) {
 281                 i++;
 282 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, CLIENT_ADDR(hc));
 283                 switch (hc->status) {
 284                 case HTTP_STREAMING: /* nothing to do */
 285                 case HTTP_READY_TO_STREAM:
 286                         break;
 287                 case HTTP_CONNECTED: /* need to recv get request */
 288                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 289                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 290                                                 < 0) {
 291                                         hc->status = HTTP_INVALID_GET_REQUEST;
 292                                 } else {
 293                                         hc->status = HTTP_GOT_GET_REQUEST;
 294                                         PARA_INFO_LOG("%s",
 295                                                 "received get request\n");
 296                                 }
 297                         }
 298                         break;
 299                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 300                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 301                                 hc->status = HTTP_SENT_OK_MSG;
 302                                 http_send_ok_msg(hc);
 303                         }
 304                         break;
 305                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 306                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 307                                 if (http_send_err_msg(hc) >= 0)
 308                                         http_shutdown_client(hc,
 309                                                 "invalid get request");
 310                         }
 311                         break;
 312                 case HTTP_SENT_OK_MSG: /* need to send header? */
 313                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 314                                 hc->status = HTTP_READY_TO_STREAM;
 315                         break;
 316                 }
 317         }
 318         if (!FD_ISSET(server_fd, rfds))
 319                 return;
 320         hc = para_calloc(sizeof(struct http_client));
 321         err_msg = "accept error";
 322         hc->fd = para_accept(server_fd, &hc->addr, sizeof(struct sockaddr_in));
 323         if (hc->fd <= 0)
 324                 goto err_out;
 325         PARA_NOTICE_LOG("connection from %s (fd %d)\n", CLIENT_ADDR(hc), hc->fd);
 326         if (conf.http_max_clients_arg > 0 && numclients >=
 327                         conf.http_max_clients_arg) {
 328                 err_msg = "server full";
 329                 goto err_out;
 330         }
 331         match = host_in_access_perm_list(hc);
 332         PARA_DEBUG_LOG("host_in_access_perm_list: %d\n", match);
 333         if ((match && !conf.http_default_deny_given) ||
 334                         (!match && conf.http_default_deny_given)) {
 335                 err_msg = "permission denied";
 336                 goto err_out;
 337         }
 338         hc->status = HTTP_CONNECTED;
 339         INIT_LIST_HEAD(&hc->chunk_queue);
 340         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 341                 CLIENT_ADDR(hc), hc->fd);
 342         numclients++;
 343         para_list_add(&hc->node, &clients);
 344         add_close_on_fork_list(hc->fd);
 345         mark_fd_nonblock(hc->fd);
 346         return;
 347 err_out:
 348         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 349                 CLIENT_ADDR(hc), err_msg);
 350         if (hc->fd > 0)
 351                 close(hc->fd);
 352         free(hc);
 353 }
 354
 355 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 356 {
 357         struct http_client *hc, *tmp;
 358
 359         if (server_fd < 0)
 360                 return;
 361         para_fd_set(server_fd, rfds, max_fileno);
 362         list_for_each_entry_safe(hc, tmp, &clients, node) {
 363                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 364                 hc->check_r = 0;
 365                 hc->check_w = 0;
 366                 switch (hc->status) {
 367                 case HTTP_STREAMING:
 368                 case HTTP_READY_TO_STREAM:
 369                         break;
 370                 case HTTP_CONNECTED: /* need to recv get request */
 371                         para_fd_set(hc->fd, rfds, max_fileno);
 372                         hc->check_r = 1;
 373                         break;
 374                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 375                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 376                         para_fd_set(hc->fd, wfds, max_fileno);
 377                         hc->check_w = 1;
 378                         break;
 379                 case HTTP_SENT_OK_MSG:
 380                         if (!vss_playing())
 381                                 break; /* wait until server starts playing */
 382                         para_fd_set(hc->fd, wfds, max_fileno);
 383                         hc->check_w = 1;
 384                         break;
 385                 }
 386         }
 387 }
 388
 389 static int open_tcp_port(int port)
 390 {
 391         int ret;
 392
 393         server_fd = init_tcp_socket(port);
 394         if (server_fd < 0) {
 395                 http_shutdown_clients();
 396                 self->status = SENDER_OFF;
 397                 return server_fd;
 398         }
 399         ret = mark_fd_nonblock(server_fd);
 400         if (ret < 0) {
 401                 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
 402                 exit(EXIT_FAILURE);
 403         }
 404         self->status = SENDER_ON;
 405         add_close_on_fork_list(server_fd);
 406         return 1;
 407 }
 408
 409 static int http_com_on(__a_unused struct sender_command_data *scd)
 410 {
 411         if (self->status == SENDER_ON)
 412                 return 1;
 413         return open_tcp_port(conf.http_port_arg);
 414 }
 415
 416 static int http_com_off(__a_unused struct sender_command_data *scd)
 417 {
 418         self->status = SENDER_OFF;
 419         if (server_fd > 0) {
 420                 close(server_fd);
 421                 del_close_on_fork_list(server_fd);
 422                 server_fd = -1;
 423         }
 424         http_shutdown_clients();
 425         return 1;
 426 }
 427
 428 static void del_perm_list_entry(struct sender_command_data *scd)
 429 {
 430         struct access_info *ai, *tmp;
 431
 432         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 433                 char *nad = para_strdup(inet_ntoa(ai->addr));
 434                 if (!strcmp(nad, inet_ntoa(scd->addr)) &&
 435                                 ai->netmask == scd->netmask) {
 436                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 437                                 nad, ai->netmask);
 438                         list_del(&ai->node);
 439                         free(ai);
 440                 }
 441                 free(nad);
 442         }
 443 }
 444
 445 static void add_perm_list_entry(struct sender_command_data *scd)
 446 {
 447         struct access_info *ai = para_malloc(sizeof(struct access_info));
 448         ai->addr = scd->addr;
 449         ai->netmask = scd->netmask;
 450         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 451                 ai->netmask);
 452         para_list_add(&ai->node, &access_perm_list);
 453 }
 454
 455 static int http_com_deny(struct sender_command_data *scd)
 456 {
 457         if (conf.http_default_deny_given)
 458                 del_perm_list_entry(scd);
 459         else
 460                 add_perm_list_entry(scd);
 461         return 1;
 462 }
 463
 464 static int http_com_allow(struct sender_command_data *scd)
 465 {
 466         if (conf.http_default_deny_given)
 467                 add_perm_list_entry(scd);
 468         else
 469                 del_perm_list_entry(scd);
 470         return 1;
 471 }
 472
 473 static char *http_info(void)
 474 {
 475         char *clnts = NULL, *ap = NULL, *ret;
 476         struct access_info *ai, *tmp_ai;
 477         struct http_client *hc, *tmp_hc;
 478
 479         list_for_each_entry_safe(ai, tmp_ai, &access_perm_list, node) {
 480                 char *tmp = make_message("%s%s/%d ", ap? ap : "",
 481                         inet_ntoa(ai->addr), ai->netmask);
 482                 free(ap);
 483                 ap = tmp;
 484         }
 485         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 486                 char *tmp = make_message("%s%s:%d ", clnts? clnts : "",
 487                         CLIENT_ADDR(hc), CLIENT_PORT(hc));
 488                 free(clnts);
 489                 clnts = tmp;
 490         }
 491         ret = make_message(
 492                 "http status: %s\n"
 493                 "http tcp port: %d\n"
 494                 "http clients: %d\n"
 495                 "http maximal number of clients: %d%s\n"
 496                 "http connected clients: %s\n"
 497                 "http access %s list: %s\n",
 498                 (self->status == SENDER_ON)? "on" : "off",
 499                 conf.http_port_arg,
 500                 numclients,
 501                 conf.http_max_clients_arg,
 502                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 503                 clnts? clnts : "(none)",
 504                 conf.http_default_deny_given? "allow" : "deny",
 505                 ap? ap : "(none)"
 506         );
 507         free(ap);
 508         free(clnts);
 509         return ret;
 510 }
 511
 512 static void init_access_control_list(void)
 513 {
 514         int i;
 515         struct sender_command_data scd;
 516
 517         INIT_LIST_HEAD(&access_perm_list);
 518         for (i = 0; i < conf.http_access_given; i++) {
 519                 char *arg = para_strdup(conf.http_access_arg[i]);
 520                 char *p = strchr(arg, '/');
 521                 if (!p)
 522                         goto err;
 523                 *p = '\0';
 524                 if (!inet_aton(arg, &scd.addr))
 525                         goto err;
 526                 scd.netmask = atoi(++p);
 527                 if (scd.netmask < 0 || scd.netmask > 32)
 528                         goto err;
 529                 add_perm_list_entry(&scd);
 530                 goto success;
 531 err:
 532                 PARA_CRIT_LOG("syntax error for http_access option "
 533                         "#%d, ignoring\n", i);
 534 success:
 535                 free(arg);
 536                 continue;
 537         }
 538 }
 539
 540 static char *http_help(void)
 541 {
 542         return make_message(
 543                 "usage: {on|off}\n"
 544                 "usage: {allow|deny} IP mask\n"
 545                 "example: allow 127.0.0.1 32\n"
 546         );
 547 }
 548
 549 /**
 550  * The init function of the http sender.
 551  *
 552  * \param s Pointer to the http sender struct.
 553  *
 554  * It initializes all function pointers of \a s, the client list and the access
 555  * control list. If the autostart option was given, the tcp port is opened.
 556  */
 557 void http_send_init(struct sender *s)
 558 {
 559         INIT_LIST_HEAD(&clients);
 560         s->info = http_info;
 561         s->send = http_send;
 562         s->pre_select = http_pre_select;
 563         s->post_select = http_post_select;
 564         s->shutdown_clients = http_shutdown_clients;
 565         s->help = http_help;
 566         s->client_cmds[SENDER_ON] = http_com_on;
 567         s->client_cmds[SENDER_OFF] = http_com_off;
 568         s->client_cmds[SENDER_DENY] = http_com_deny;
 569         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 570         s->client_cmds[SENDER_ADD] = NULL;
 571         s->client_cmds[SENDER_DELETE] = NULL;
 572         self = s;
 573         init_access_control_list();
 574         if (!conf.http_no_autostart_given)
 575                 open_tcp_port(conf.http_port_arg); /* ignore errors */
 576         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 577 }