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 400000
  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 struct chunk_queue{
  53         /** The list of pending chunks for this client. */
  54         struct list_head q;
  55         /** The number of pending bytes for this client. */
  56         unsigned long num_pending;
  57         unsigned long max_pending;
  58 };
  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 chunks for this client. */
  75         struct chunk_queue cq;
  76 };
  77
  78 /**
  79  * Describes one queued chunk of the chunk queue.
  80  *
  81  * The send function of the http sender checks each client fd for writing. If a
  82  * client fd is not ready, it tries to queue that chunk for this client until
  83  * the number of queued bytes exceeds \p MAX_BACKLOG.
  84  */
  85 struct queued_chunk {
  86         /** The number of the queued chunk, -1U means header. */
  87         unsigned chunk_num;
  88         /** The number of bytes already sent. */
  89         unsigned sent;
  90         /** Position of the chunk in the chunk queue. */
  91         struct list_head node;
  92 };
  93
  94 /**
  95  * Describes one entry in the blacklist/whitelist of the http sender.
  96  */
  97 struct access_info {
  98         /** The address to be black/whitelisted. */
  99         struct in_addr addr;
 100         /** The netmask for this entry. */
 101         unsigned netmask;
 102         /** The position of this entry in the access_perm_list. */
 103         struct list_head node;
 104 };
 105
 106 static int server_fd = -1, numclients;
 107 static struct sender *self;
 108
 109
 110 static int cq_enqueue(struct chunk_queue *cq, long unsigned chunk_num,
 111         size_t sent)
 112 {
 113         struct queued_chunk *qc;
 114         char *buf;
 115         size_t len;
 116         int ret;
 117
 118         if (chunk_num != -1U) {
 119                 ret = vss_get_chunk(chunk_num, &buf, &len);
 120                 if (ret < 0)
 121                         return ret;
 122         } else
 123                 buf = vss_get_header(&len);
 124         if (cq->num_pending + len > cq->max_pending)
 125                 return -E_QUEUE;
 126         qc = para_malloc(sizeof(struct queued_chunk));
 127         cq->num_pending += len;
 128         qc->chunk_num = chunk_num;
 129         qc->sent = sent;
 130         list_add_tail(&qc->node, &cq->q);
 131         PARA_DEBUG_LOG("%lu bytes queued for %p\n", cq->num_pending, &cq->q);
 132         return 1;
 133 }
 134
 135 static struct queued_chunk *cq_peek(struct chunk_queue *cq)
 136 {
 137         if (list_empty(&cq->q))
 138                 return NULL;
 139         return list_entry(cq->q.next, struct queued_chunk, node);
 140 }
 141
 142 int cq_dequeue(struct chunk_queue *cq)
 143 {
 144         struct queued_chunk *qc = cq_peek(cq);
 145         assert(qc);
 146         list_del(&qc->node);
 147         free(qc);
 148         return 1;
 149 }
 150
 151 void cq_update(struct chunk_queue *cq, size_t sent)
 152 {
 153         struct queued_chunk *qc = cq_peek(cq);
 154         assert(qc);
 155         qc->sent += sent;
 156         cq->num_pending -= sent;
 157 }
 158
 159 int cq_get(struct queued_chunk *qc, char **buf, size_t *len)
 160 {
 161         int ret;
 162
 163         if (qc->chunk_num != -1U) {
 164                 ret = vss_get_chunk(qc->chunk_num, buf, len);
 165                 if (ret < 0)
 166                         return ret;
 167         } else
 168                 *buf = vss_get_header(len);
 169         assert(*len > qc->sent);
 170         *buf += qc->sent;
 171         *len -= qc->sent;
 172         return 1;
 173 }
 174
 175 void cq_init(struct chunk_queue *cq, size_t max_pending)
 176 {
 177         INIT_LIST_HEAD(&cq->q);
 178         cq->max_pending = max_pending;
 179         cq->num_pending = 0;
 180 }
 181
 182 void cq_destroy(struct chunk_queue *cq)
 183 {
 184         struct queued_chunk *qc, *tmp;
 185         list_for_each_entry_safe(qc, tmp, &cq->q, node) {
 186                 list_del(&qc->node);
 187                 free(qc);
 188         }
 189 }
 190
 191 static void http_shutdown_client(struct http_client *hc, const char *msg)
 192 {
 193         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", CLIENT_ADDR(hc),
 194                 hc->fd, msg);
 195         numclients--;
 196         close(hc->fd);
 197         del_close_on_fork_list(hc->fd);
 198         cq_destroy(&hc->cq);
 199         list_del(&hc->node);
 200         free(hc);
 201 }
 202
 203 static void http_shutdown_clients(void)
 204 {
 205         struct http_client *hc, *tmp;
 206         list_for_each_entry_safe(hc, tmp, &clients, node)
 207                 http_shutdown_client(hc, "vss request");
 208 }
 209
 210 static int http_send_msg(struct http_client *hc, const char *msg)
 211 {
 212         int ret = send_buffer(hc->fd, msg);
 213
 214         if (ret < 0)
 215                 http_shutdown_client(hc, "send msg failed");
 216         return ret;
 217 }
 218
 219 static void http_send_ok_msg(struct http_client *hc)
 220 {
 221         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 222         http_send_msg(hc, HTTP_OK_MSG);
 223 }
 224
 225 static int http_send_err_msg(struct http_client *hc)
 226 {
 227         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 228         return http_send_msg(hc, HTTP_ERR_MSG);
 229 }
 230
 231
 232 static int send_queued_chunks(struct http_client *hc)
 233 {
 234         struct queued_chunk *qc;
 235         while ((qc = cq_peek(&hc->cq))) {
 236                 char *buf;
 237                 size_t len;
 238                 int ret = write_ok(hc->fd);
 239                 if (ret <= 0)
 240                         return ret? -E_WRITE_OK : 0;
 241                 cq_get(qc, &buf, &len);
 242                 ret = write(hc->fd, buf, len);
 243                 if (ret < 0)
 244                         return -1; /* FIXME */
 245                 cq_update(&hc->cq, ret);
 246                 if (ret != len)
 247                         return 1;
 248                 cq_dequeue(&hc->cq);
 249         }
 250         return 1;
 251 }
 252
 253 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 254         size_t sent)
 255 {
 256         int ret = cq_enqueue(&hc->cq, chunk_num, sent);
 257         if (ret < 0)
 258                 http_shutdown_client(hc, "queue error");
 259         return ret;
 260 }
 261
 262 static void http_send( long unsigned current_chunk,
 263         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 264 {
 265         struct http_client *hc, *tmp;
 266         int ret;
 267
 268         list_for_each_entry_safe(hc, tmp, &clients, node) {
 269                 if (hc->status != HTTP_STREAMING &&
 270                                 hc->status != HTTP_READY_TO_STREAM)
 271                         continue;
 272                 if (hc->status == HTTP_READY_TO_STREAM) {
 273                         unsigned hlen;
 274                         char *hbuf = vss_get_header(&hlen);
 275                         if (hbuf && hlen > 0 && current_chunk) {
 276                                 /* need to send header */
 277                                 PARA_INFO_LOG("queueing header: %d\n", hlen);
 278                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 279                                         continue;
 280                         } else
 281                                 PARA_INFO_LOG("no need to queue header\n");
 282                         hc->status = HTTP_STREAMING;
 283                 }
 284                 ret = send_queued_chunks(hc);
 285                 if (ret < 0) {
 286                         http_shutdown_client(hc, "queue send error");
 287                         continue;
 288                 }
 289                 if (!len)
 290                         continue;
 291                 if (!ret || write_ok(hc->fd) <= 0) {
 292                         queue_chunk_or_shutdown(hc, current_chunk, 0);
 293                         continue;
 294                 }
 295 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, CLIENT_ADDR(hc));
 296                 ret = write(hc->fd, buf, len);
 297 //              PARA_DEBUG_LOG("ret: %d\n", ret);
 298                 if (ret < 0) {
 299                         http_shutdown_client(hc, "send error");
 300                         continue;
 301                 }
 302                 if (ret != len)
 303                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 304         }
 305 }
 306
 307 static int host_in_access_perm_list(struct http_client *hc)
 308 {
 309         struct access_info *ai, *tmp;
 310         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 311                 unsigned mask = ((~0U) >> ai->netmask);
 312                 if ((hc->addr.sin_addr.s_addr & mask) == (ai->addr.s_addr & mask))
 313                         return 1;
 314         }
 315         return 0;
 316 }
 317
 318 static void http_post_select(fd_set *rfds, fd_set *wfds)
 319 {
 320         int i = -1, match;
 321         struct http_client *hc, *tmp;
 322         const char *err_msg;
 323
 324         list_for_each_entry_safe(hc, tmp, &clients, node) {
 325                 i++;
 326 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, CLIENT_ADDR(hc));
 327                 switch (hc->status) {
 328                 case HTTP_STREAMING: /* nothing to do */
 329                 case HTTP_READY_TO_STREAM:
 330                         break;
 331                 case HTTP_CONNECTED: /* need to recv get request */
 332                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 333                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 334                                                 < 0) {
 335                                         hc->status = HTTP_INVALID_GET_REQUEST;
 336                                 } else {
 337                                         hc->status = HTTP_GOT_GET_REQUEST;
 338                                         PARA_INFO_LOG("%s",
 339                                                 "received get request\n");
 340                                 }
 341                         }
 342                         break;
 343                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 344                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 345                                 hc->status = HTTP_SENT_OK_MSG;
 346                                 http_send_ok_msg(hc);
 347                         }
 348                         break;
 349                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 350                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 351                                 if (http_send_err_msg(hc) >= 0)
 352                                         http_shutdown_client(hc,
 353                                                 "invalid get request");
 354                         }
 355                         break;
 356                 case HTTP_SENT_OK_MSG: /* need to send header? */
 357                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 358                                 hc->status = HTTP_READY_TO_STREAM;
 359                         break;
 360                 }
 361         }
 362         if (!FD_ISSET(server_fd, rfds))
 363                 return;
 364         hc = para_calloc(sizeof(struct http_client));
 365         err_msg = "accept error";
 366         hc->fd = para_accept(server_fd, &hc->addr, sizeof(struct sockaddr_in));
 367         if (hc->fd <= 0)
 368                 goto err_out;
 369         PARA_NOTICE_LOG("connection from %s (fd %d)\n", CLIENT_ADDR(hc), hc->fd);
 370         if (conf.http_max_clients_arg > 0 && numclients >=
 371                         conf.http_max_clients_arg) {
 372                 err_msg = "server full";
 373                 goto err_out;
 374         }
 375         match = host_in_access_perm_list(hc);
 376         PARA_DEBUG_LOG("host_in_access_perm_list: %d\n", match);
 377         if ((match && !conf.http_default_deny_given) ||
 378                         (!match && conf.http_default_deny_given)) {
 379                 err_msg = "permission denied";
 380                 goto err_out;
 381         }
 382         hc->status = HTTP_CONNECTED;
 383         cq_init(&hc->cq, MAX_BACKLOG);
 384         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 385                 CLIENT_ADDR(hc), hc->fd);
 386         numclients++;
 387         para_list_add(&hc->node, &clients);
 388         add_close_on_fork_list(hc->fd);
 389         mark_fd_nonblock(hc->fd);
 390         return;
 391 err_out:
 392         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 393                 CLIENT_ADDR(hc), err_msg);
 394         if (hc->fd > 0)
 395                 close(hc->fd);
 396         free(hc);
 397 }
 398
 399 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 400 {
 401         struct http_client *hc, *tmp;
 402
 403         if (server_fd < 0)
 404                 return;
 405         para_fd_set(server_fd, rfds, max_fileno);
 406         list_for_each_entry_safe(hc, tmp, &clients, node) {
 407                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 408                 hc->check_r = 0;
 409                 hc->check_w = 0;
 410                 switch (hc->status) {
 411                 case HTTP_STREAMING:
 412                 case HTTP_READY_TO_STREAM:
 413                         break;
 414                 case HTTP_CONNECTED: /* need to recv get request */
 415                         para_fd_set(hc->fd, rfds, max_fileno);
 416                         hc->check_r = 1;
 417                         break;
 418                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 419                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 420                         para_fd_set(hc->fd, wfds, max_fileno);
 421                         hc->check_w = 1;
 422                         break;
 423                 case HTTP_SENT_OK_MSG:
 424                         if (!vss_playing())
 425                                 break; /* wait until server starts playing */
 426                         para_fd_set(hc->fd, wfds, max_fileno);
 427                         hc->check_w = 1;
 428                         break;
 429                 }
 430         }
 431 }
 432
 433 static int open_tcp_port(int port)
 434 {
 435         int ret;
 436
 437         server_fd = init_tcp_socket(port);
 438         if (server_fd < 0) {
 439                 http_shutdown_clients();
 440                 self->status = SENDER_OFF;
 441                 return server_fd;
 442         }
 443         ret = mark_fd_nonblock(server_fd);
 444         if (ret < 0) {
 445                 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
 446                 exit(EXIT_FAILURE);
 447         }
 448         self->status = SENDER_ON;
 449         add_close_on_fork_list(server_fd);
 450         return 1;
 451 }
 452
 453 static int http_com_on(__a_unused struct sender_command_data *scd)
 454 {
 455         if (self->status == SENDER_ON)
 456                 return 1;
 457         return open_tcp_port(conf.http_port_arg);
 458 }
 459
 460 static int http_com_off(__a_unused struct sender_command_data *scd)
 461 {
 462         self->status = SENDER_OFF;
 463         if (server_fd > 0) {
 464                 close(server_fd);
 465                 del_close_on_fork_list(server_fd);
 466                 server_fd = -1;
 467         }
 468         http_shutdown_clients();
 469         return 1;
 470 }
 471
 472 static void del_perm_list_entry(struct sender_command_data *scd)
 473 {
 474         struct access_info *ai, *tmp;
 475
 476         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 477                 char *nad = para_strdup(inet_ntoa(ai->addr));
 478                 if (!strcmp(nad, inet_ntoa(scd->addr)) &&
 479                                 ai->netmask == scd->netmask) {
 480                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 481                                 nad, ai->netmask);
 482                         list_del(&ai->node);
 483                         free(ai);
 484                 }
 485                 free(nad);
 486         }
 487 }
 488
 489 static void add_perm_list_entry(struct sender_command_data *scd)
 490 {
 491         struct access_info *ai = para_malloc(sizeof(struct access_info));
 492         ai->addr = scd->addr;
 493         ai->netmask = scd->netmask;
 494         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 495                 ai->netmask);
 496         para_list_add(&ai->node, &access_perm_list);
 497 }
 498
 499 static int http_com_deny(struct sender_command_data *scd)
 500 {
 501         if (conf.http_default_deny_given)
 502                 del_perm_list_entry(scd);
 503         else
 504                 add_perm_list_entry(scd);
 505         return 1;
 506 }
 507
 508 static int http_com_allow(struct sender_command_data *scd)
 509 {
 510         if (conf.http_default_deny_given)
 511                 add_perm_list_entry(scd);
 512         else
 513                 del_perm_list_entry(scd);
 514         return 1;
 515 }
 516
 517 static char *http_info(void)
 518 {
 519         char *clnts = NULL, *ap = NULL, *ret;
 520         struct access_info *ai, *tmp_ai;
 521         struct http_client *hc, *tmp_hc;
 522
 523         list_for_each_entry_safe(ai, tmp_ai, &access_perm_list, node) {
 524                 char *tmp = make_message("%s%s/%d ", ap? ap : "",
 525                         inet_ntoa(ai->addr), ai->netmask);
 526                 free(ap);
 527                 ap = tmp;
 528         }
 529         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 530                 char *tmp = make_message("%s%s:%d ", clnts? clnts : "",
 531                         CLIENT_ADDR(hc), CLIENT_PORT(hc));
 532                 free(clnts);
 533                 clnts = tmp;
 534         }
 535         ret = make_message(
 536                 "http status: %s\n"
 537                 "http tcp port: %d\n"
 538                 "http clients: %d\n"
 539                 "http maximal number of clients: %d%s\n"
 540                 "http connected clients: %s\n"
 541                 "http access %s list: %s\n",
 542                 (self->status == SENDER_ON)? "on" : "off",
 543                 conf.http_port_arg,
 544                 numclients,
 545                 conf.http_max_clients_arg,
 546                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 547                 clnts? clnts : "(none)",
 548                 conf.http_default_deny_given? "allow" : "deny",
 549                 ap? ap : "(none)"
 550         );
 551         free(ap);
 552         free(clnts);
 553         return ret;
 554 }
 555
 556 static void init_access_control_list(void)
 557 {
 558         int i;
 559         struct sender_command_data scd;
 560
 561         INIT_LIST_HEAD(&access_perm_list);
 562         for (i = 0; i < conf.http_access_given; i++) {
 563                 char *arg = para_strdup(conf.http_access_arg[i]);
 564                 char *p = strchr(arg, '/');
 565                 if (!p)
 566                         goto err;
 567                 *p = '\0';
 568                 if (!inet_aton(arg, &scd.addr))
 569                         goto err;
 570                 scd.netmask = atoi(++p);
 571                 if (scd.netmask < 0 || scd.netmask > 32)
 572                         goto err;
 573                 add_perm_list_entry(&scd);
 574                 goto success;
 575 err:
 576                 PARA_CRIT_LOG("syntax error for http_access option "
 577                         "#%d, ignoring\n", i);
 578 success:
 579                 free(arg);
 580                 continue;
 581         }
 582 }
 583
 584 static char *http_help(void)
 585 {
 586         return make_message(
 587                 "usage: {on|off}\n"
 588                 "usage: {allow|deny} IP mask\n"
 589                 "example: allow 127.0.0.1 32\n"
 590         );
 591 }
 592
 593 /**
 594  * The init function of the http sender.
 595  *
 596  * \param s Pointer to the http sender struct.
 597  *
 598  * It initializes all function pointers of \a s, the client list and the access
 599  * control list. If the autostart option was given, the tcp port is opened.
 600  */
 601 void http_send_init(struct sender *s)
 602 {
 603         INIT_LIST_HEAD(&clients);
 604         s->info = http_info;
 605         s->send = http_send;
 606         s->pre_select = http_pre_select;
 607         s->post_select = http_post_select;
 608         s->shutdown_clients = http_shutdown_clients;
 609         s->help = http_help;
 610         s->client_cmds[SENDER_ON] = http_com_on;
 611         s->client_cmds[SENDER_OFF] = http_com_off;
 612         s->client_cmds[SENDER_DENY] = http_com_deny;
 613         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 614         s->client_cmds[SENDER_ADD] = NULL;
 615         s->client_cmds[SENDER_DELETE] = NULL;
 616         self = s;
 617         init_access_control_list();
 618         if (!conf.http_no_autostart_given)
 619                 open_tcp_port(conf.http_port_arg); /* ignore errors */
 620         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 621 }