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 struct chunk_queue *cq_init(size_t max_pending)
 176 {
 177         struct chunk_queue *cq = para_malloc(sizeof(*cq));
 178         INIT_LIST_HEAD(&cq->q);
 179         cq->max_pending = max_pending;
 180         cq->num_pending = 0;
 181         return cq;
 182 }
 183
 184 void cq_destroy(struct chunk_queue *cq)
 185 {
 186         struct queued_chunk *qc, *tmp;
 187         list_for_each_entry_safe(qc, tmp, &cq->q, node) {
 188                 list_del(&qc->node);
 189                 free(qc);
 190         }
 191         free(cq);
 192 }
 193
 194 static void http_shutdown_client(struct http_client *hc, const char *msg)
 195 {
 196         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", CLIENT_ADDR(hc),
 197                 hc->fd, msg);
 198         numclients--;
 199         close(hc->fd);
 200         del_close_on_fork_list(hc->fd);
 201         cq_destroy(hc->cq);
 202         list_del(&hc->node);
 203         free(hc);
 204 }
 205
 206 static void http_shutdown_clients(void)
 207 {
 208         struct http_client *hc, *tmp;
 209         list_for_each_entry_safe(hc, tmp, &clients, node)
 210                 http_shutdown_client(hc, "vss request");
 211 }
 212
 213 static int http_send_msg(struct http_client *hc, const char *msg)
 214 {
 215         int ret = send_buffer(hc->fd, msg);
 216
 217         if (ret < 0)
 218                 http_shutdown_client(hc, "send msg failed");
 219         return ret;
 220 }
 221
 222 static void http_send_ok_msg(struct http_client *hc)
 223 {
 224         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 225         http_send_msg(hc, HTTP_OK_MSG);
 226 }
 227
 228 static int http_send_err_msg(struct http_client *hc)
 229 {
 230         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 231         return http_send_msg(hc, HTTP_ERR_MSG);
 232 }
 233
 234
 235 static int send_queued_chunks(struct http_client *hc)
 236 {
 237         struct queued_chunk *qc;
 238         while ((qc = cq_peek(hc->cq))) {
 239                 char *buf;
 240                 size_t len;
 241                 int ret = write_ok(hc->fd);
 242                 if (ret <= 0)
 243                         return ret? -E_WRITE_OK : 0;
 244                 cq_get(qc, &buf, &len);
 245                 ret = write(hc->fd, buf, len);
 246                 if (ret < 0)
 247                         return -1; /* FIXME */
 248                 cq_update(hc->cq, ret);
 249                 if (ret != len)
 250                         return 1;
 251                 cq_dequeue(hc->cq);
 252         }
 253         return 1;
 254 }
 255
 256 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 257         size_t sent)
 258 {
 259         int ret = cq_enqueue(hc->cq, chunk_num, sent);
 260         if (ret < 0)
 261                 http_shutdown_client(hc, "queue error");
 262         return ret;
 263 }
 264
 265 static void http_send( long unsigned current_chunk,
 266         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 267 {
 268         struct http_client *hc, *tmp;
 269         int ret;
 270
 271         list_for_each_entry_safe(hc, tmp, &clients, node) {
 272                 if (hc->status != HTTP_STREAMING &&
 273                                 hc->status != HTTP_READY_TO_STREAM)
 274                         continue;
 275                 if (hc->status == HTTP_READY_TO_STREAM) {
 276                         unsigned hlen;
 277                         char *hbuf = vss_get_header(&hlen);
 278                         if (hbuf && hlen > 0 && current_chunk) {
 279                                 /* need to send header */
 280                                 PARA_INFO_LOG("queueing header: %d\n", hlen);
 281                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 282                                         continue;
 283                         } else
 284                                 PARA_INFO_LOG("no need to queue header\n");
 285                         hc->status = HTTP_STREAMING;
 286                 }
 287                 ret = send_queued_chunks(hc);
 288                 if (ret < 0) {
 289                         http_shutdown_client(hc, "queue send error");
 290                         continue;
 291                 }
 292                 if (!len)
 293                         continue;
 294                 if (!ret || write_ok(hc->fd) <= 0) {
 295                         queue_chunk_or_shutdown(hc, current_chunk, 0);
 296                         continue;
 297                 }
 298 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, CLIENT_ADDR(hc));
 299                 ret = write(hc->fd, buf, len);
 300 //              PARA_DEBUG_LOG("ret: %d\n", ret);
 301                 if (ret < 0) {
 302                         http_shutdown_client(hc, "send error");
 303                         continue;
 304                 }
 305                 if (ret != len)
 306                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 307         }
 308 }
 309
 310 static int host_in_access_perm_list(struct http_client *hc)
 311 {
 312         struct access_info *ai, *tmp;
 313         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 314                 unsigned mask = ((~0U) >> ai->netmask);
 315                 if ((hc->addr.sin_addr.s_addr & mask) == (ai->addr.s_addr & mask))
 316                         return 1;
 317         }
 318         return 0;
 319 }
 320
 321 static void http_post_select(fd_set *rfds, fd_set *wfds)
 322 {
 323         int i = -1, match;
 324         struct http_client *hc, *tmp;
 325         const char *err_msg;
 326
 327         list_for_each_entry_safe(hc, tmp, &clients, node) {
 328                 i++;
 329 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, CLIENT_ADDR(hc));
 330                 switch (hc->status) {
 331                 case HTTP_STREAMING: /* nothing to do */
 332                 case HTTP_READY_TO_STREAM:
 333                         break;
 334                 case HTTP_CONNECTED: /* need to recv get request */
 335                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 336                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 337                                                 < 0) {
 338                                         hc->status = HTTP_INVALID_GET_REQUEST;
 339                                 } else {
 340                                         hc->status = HTTP_GOT_GET_REQUEST;
 341                                         PARA_INFO_LOG("%s",
 342                                                 "received get request\n");
 343                                 }
 344                         }
 345                         break;
 346                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 347                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 348                                 hc->status = HTTP_SENT_OK_MSG;
 349                                 http_send_ok_msg(hc);
 350                         }
 351                         break;
 352                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 353                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 354                                 if (http_send_err_msg(hc) >= 0)
 355                                         http_shutdown_client(hc,
 356                                                 "invalid get request");
 357                         }
 358                         break;
 359                 case HTTP_SENT_OK_MSG: /* need to send header? */
 360                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 361                                 hc->status = HTTP_READY_TO_STREAM;
 362                         break;
 363                 }
 364         }
 365         if (!FD_ISSET(server_fd, rfds))
 366                 return;
 367         hc = para_calloc(sizeof(struct http_client));
 368         err_msg = "accept error";
 369         hc->fd = para_accept(server_fd, &hc->addr, sizeof(struct sockaddr_in));
 370         if (hc->fd <= 0)
 371                 goto err_out;
 372         PARA_NOTICE_LOG("connection from %s (fd %d)\n", CLIENT_ADDR(hc), hc->fd);
 373         if (conf.http_max_clients_arg > 0 && numclients >=
 374                         conf.http_max_clients_arg) {
 375                 err_msg = "server full";
 376                 goto err_out;
 377         }
 378         match = host_in_access_perm_list(hc);
 379         PARA_DEBUG_LOG("host_in_access_perm_list: %d\n", match);
 380         if ((match && !conf.http_default_deny_given) ||
 381                         (!match && conf.http_default_deny_given)) {
 382                 err_msg = "permission denied";
 383                 goto err_out;
 384         }
 385         hc->status = HTTP_CONNECTED;
 386         hc->cq = cq_init(MAX_BACKLOG);
 387         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 388                 CLIENT_ADDR(hc), hc->fd);
 389         numclients++;
 390         para_list_add(&hc->node, &clients);
 391         add_close_on_fork_list(hc->fd);
 392         mark_fd_nonblock(hc->fd);
 393         return;
 394 err_out:
 395         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 396                 CLIENT_ADDR(hc), err_msg);
 397         if (hc->fd > 0)
 398                 close(hc->fd);
 399         free(hc);
 400 }
 401
 402 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 403 {
 404         struct http_client *hc, *tmp;
 405
 406         if (server_fd < 0)
 407                 return;
 408         para_fd_set(server_fd, rfds, max_fileno);
 409         list_for_each_entry_safe(hc, tmp, &clients, node) {
 410                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 411                 hc->check_r = 0;
 412                 hc->check_w = 0;
 413                 switch (hc->status) {
 414                 case HTTP_STREAMING:
 415                 case HTTP_READY_TO_STREAM:
 416                         break;
 417                 case HTTP_CONNECTED: /* need to recv get request */
 418                         para_fd_set(hc->fd, rfds, max_fileno);
 419                         hc->check_r = 1;
 420                         break;
 421                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 422                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 423                         para_fd_set(hc->fd, wfds, max_fileno);
 424                         hc->check_w = 1;
 425                         break;
 426                 case HTTP_SENT_OK_MSG:
 427                         if (!vss_playing())
 428                                 break; /* wait until server starts playing */
 429                         para_fd_set(hc->fd, wfds, max_fileno);
 430                         hc->check_w = 1;
 431                         break;
 432                 }
 433         }
 434 }
 435
 436 static int open_tcp_port(int port)
 437 {
 438         int ret;
 439
 440         server_fd = init_tcp_socket(port);
 441         if (server_fd < 0) {
 442                 http_shutdown_clients();
 443                 self->status = SENDER_OFF;
 444                 return server_fd;
 445         }
 446         ret = mark_fd_nonblock(server_fd);
 447         if (ret < 0) {
 448                 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
 449                 exit(EXIT_FAILURE);
 450         }
 451         self->status = SENDER_ON;
 452         add_close_on_fork_list(server_fd);
 453         return 1;
 454 }
 455
 456 static int http_com_on(__a_unused struct sender_command_data *scd)
 457 {
 458         if (self->status == SENDER_ON)
 459                 return 1;
 460         return open_tcp_port(conf.http_port_arg);
 461 }
 462
 463 static int http_com_off(__a_unused struct sender_command_data *scd)
 464 {
 465         self->status = SENDER_OFF;
 466         if (server_fd > 0) {
 467                 close(server_fd);
 468                 del_close_on_fork_list(server_fd);
 469                 server_fd = -1;
 470         }
 471         http_shutdown_clients();
 472         return 1;
 473 }
 474
 475 static void del_perm_list_entry(struct sender_command_data *scd)
 476 {
 477         struct access_info *ai, *tmp;
 478
 479         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 480                 char *nad = para_strdup(inet_ntoa(ai->addr));
 481                 if (!strcmp(nad, inet_ntoa(scd->addr)) &&
 482                                 ai->netmask == scd->netmask) {
 483                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 484                                 nad, ai->netmask);
 485                         list_del(&ai->node);
 486                         free(ai);
 487                 }
 488                 free(nad);
 489         }
 490 }
 491
 492 static void add_perm_list_entry(struct sender_command_data *scd)
 493 {
 494         struct access_info *ai = para_malloc(sizeof(struct access_info));
 495         ai->addr = scd->addr;
 496         ai->netmask = scd->netmask;
 497         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 498                 ai->netmask);
 499         para_list_add(&ai->node, &access_perm_list);
 500 }
 501
 502 static int http_com_deny(struct sender_command_data *scd)
 503 {
 504         if (conf.http_default_deny_given)
 505                 del_perm_list_entry(scd);
 506         else
 507                 add_perm_list_entry(scd);
 508         return 1;
 509 }
 510
 511 static int http_com_allow(struct sender_command_data *scd)
 512 {
 513         if (conf.http_default_deny_given)
 514                 add_perm_list_entry(scd);
 515         else
 516                 del_perm_list_entry(scd);
 517         return 1;
 518 }
 519
 520 static char *http_info(void)
 521 {
 522         char *clnts = NULL, *ap = NULL, *ret;
 523         struct access_info *ai, *tmp_ai;
 524         struct http_client *hc, *tmp_hc;
 525
 526         list_for_each_entry_safe(ai, tmp_ai, &access_perm_list, node) {
 527                 char *tmp = make_message("%s%s/%d ", ap? ap : "",
 528                         inet_ntoa(ai->addr), ai->netmask);
 529                 free(ap);
 530                 ap = tmp;
 531         }
 532         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 533                 char *tmp = make_message("%s%s:%d ", clnts? clnts : "",
 534                         CLIENT_ADDR(hc), CLIENT_PORT(hc));
 535                 free(clnts);
 536                 clnts = tmp;
 537         }
 538         ret = make_message(
 539                 "http status: %s\n"
 540                 "http tcp port: %d\n"
 541                 "http clients: %d\n"
 542                 "http maximal number of clients: %d%s\n"
 543                 "http connected clients: %s\n"
 544                 "http access %s list: %s\n",
 545                 (self->status == SENDER_ON)? "on" : "off",
 546                 conf.http_port_arg,
 547                 numclients,
 548                 conf.http_max_clients_arg,
 549                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 550                 clnts? clnts : "(none)",
 551                 conf.http_default_deny_given? "allow" : "deny",
 552                 ap? ap : "(none)"
 553         );
 554         free(ap);
 555         free(clnts);
 556         return ret;
 557 }
 558
 559 static void init_access_control_list(void)
 560 {
 561         int i;
 562         struct sender_command_data scd;
 563
 564         INIT_LIST_HEAD(&access_perm_list);
 565         for (i = 0; i < conf.http_access_given; i++) {
 566                 char *arg = para_strdup(conf.http_access_arg[i]);
 567                 char *p = strchr(arg, '/');
 568                 if (!p)
 569                         goto err;
 570                 *p = '\0';
 571                 if (!inet_aton(arg, &scd.addr))
 572                         goto err;
 573                 scd.netmask = atoi(++p);
 574                 if (scd.netmask < 0 || scd.netmask > 32)
 575                         goto err;
 576                 add_perm_list_entry(&scd);
 577                 goto success;
 578 err:
 579                 PARA_CRIT_LOG("syntax error for http_access option "
 580                         "#%d, ignoring\n", i);
 581 success:
 582                 free(arg);
 583                 continue;
 584         }
 585 }
 586
 587 static char *http_help(void)
 588 {
 589         return make_message(
 590                 "usage: {on|off}\n"
 591                 "usage: {allow|deny} IP mask\n"
 592                 "example: allow 127.0.0.1 32\n"
 593         );
 594 }
 595
 596 /**
 597  * The init function of the http sender.
 598  *
 599  * \param s Pointer to the http sender struct.
 600  *
 601  * It initializes all function pointers of \a s, the client list and the access
 602  * control list. If the autostart option was given, the tcp port is opened.
 603  */
 604 void http_send_init(struct sender *s)
 605 {
 606         INIT_LIST_HEAD(&clients);
 607         s->info = http_info;
 608         s->send = http_send;
 609         s->pre_select = http_pre_select;
 610         s->post_select = http_post_select;
 611         s->shutdown_clients = http_shutdown_clients;
 612         s->help = http_help;
 613         s->client_cmds[SENDER_ON] = http_com_on;
 614         s->client_cmds[SENDER_OFF] = http_com_off;
 615         s->client_cmds[SENDER_DENY] = http_com_deny;
 616         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 617         s->client_cmds[SENDER_ADD] = NULL;
 618         s->client_cmds[SENDER_DELETE] = NULL;
 619         self = s;
 620         init_access_control_list();
 621         if (!conf.http_no_autostart_given)
 622                 open_tcp_port(conf.http_port_arg); /* ignore errors */
 623         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 624 }