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