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