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 #include "chunk_queue.h"
  22
  23 /** \cond convert sock_addr_in to ascii */
  24 #define CLIENT_ADDR(hc) inet_ntoa((hc)->addr.sin_addr)
  25 /* get the port number of a struct http_client */
  26 #define CLIENT_PORT(hc) (hc)->addr.sin_port
  27 #define HTTP_ERR_MSG "HTTP/1.0 400 Bad Request\n"
  28 /** \endcond */
  29
  30 /** The possible states of a client from the server's POV. */
  31 enum http_status {
  32         /** We accepted the connection on the tcp socket. */
  33         HTTP_CONNECTED,
  34         /** Successfully received the get request. */
  35         HTTP_GOT_GET_REQUEST,
  36         /** We sent the OK message back to the client. */
  37         HTTP_SENT_OK_MSG,
  38         /** Connection established, we might need to send the audio file header. */
  39         HTTP_READY_TO_STREAM,
  40         /** Connection is ready for sending audio data. */
  41         HTTP_STREAMING,
  42         /** We didn't receive a valid get request. */
  43         HTTP_INVALID_GET_REQUEST
  44 };
  45
  46 /** Clients will be kicked if there are more than that many bytes pending. */
  47 #define MAX_BACKLOG 400000
  48 /** The list of connected clients. */
  49 static struct list_head clients;
  50 /** The whitelist/blacklist. */
  51 static struct list_head access_perm_list;
  52
  53 /** Describes one client that connected the tcp port of the http sender. */
  54 struct http_client {
  55         /** The file descriptor of the client. */
  56         int fd;
  57         /** Address information about the client. */
  58         struct sockaddr_in addr;
  59         /** The client's current status. */
  60         enum http_status status;
  61         /** Non-zero if we included \a fd in the read set.*/
  62         int check_r;
  63         /** Non-zero if we included \a fd in the write set. */
  64         int check_w;
  65         /** The position of this client in the client list. */
  66         struct list_head node;
  67         /** The list of pending chunks for this client. */
  68         struct chunk_queue *cq;
  69 };
  70
  71 /**
  72  * Describes one entry in the blacklist/whitelist of the http sender.
  73  */
  74 struct access_info {
  75         /** The address to be black/whitelisted. */
  76         struct in_addr addr;
  77         /** The netmask for this entry. */
  78         unsigned netmask;
  79         /** The position of this entry in the access_perm_list. */
  80         struct list_head node;
  81 };
  82
  83 static int server_fd = -1, numclients;
  84 static struct sender *self;
  85
  86
  87 static void http_shutdown_client(struct http_client *hc, const char *msg)
  88 {
  89         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", CLIENT_ADDR(hc),
  90                 hc->fd, msg);
  91         numclients--;
  92         close(hc->fd);
  93         del_close_on_fork_list(hc->fd);
  94         cq_destroy(hc->cq);
  95         list_del(&hc->node);
  96         free(hc);
  97 }
  98
  99 static void http_shutdown_clients(void)
 100 {
 101         struct http_client *hc, *tmp;
 102         list_for_each_entry_safe(hc, tmp, &clients, node)
 103                 http_shutdown_client(hc, "vss request");
 104 }
 105
 106 static int http_send_msg(struct http_client *hc, const char *msg)
 107 {
 108         int ret = send_buffer(hc->fd, msg);
 109
 110         if (ret < 0)
 111                 http_shutdown_client(hc, "send msg failed");
 112         return ret;
 113 }
 114
 115 static void http_send_ok_msg(struct http_client *hc)
 116 {
 117         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 118         http_send_msg(hc, HTTP_OK_MSG);
 119 }
 120
 121 static int http_send_err_msg(struct http_client *hc)
 122 {
 123         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 124         return http_send_msg(hc, HTTP_ERR_MSG);
 125 }
 126
 127 static int send_queued_chunks(struct http_client *hc)
 128 {
 129         struct queued_chunk *qc;
 130         while ((qc = cq_peek(hc->cq))) {
 131                 char *buf;
 132                 size_t len;
 133                 int ret = write_ok(hc->fd);
 134                 if (ret <= 0)
 135                         return ret? -E_WRITE_OK : 0;
 136                 cq_get(qc, &buf, &len);
 137                 ret = write(hc->fd, buf, len);
 138                 if (ret < 0)
 139                         return -E_SEND_QUEUED_CHUNK;
 140                 cq_update(hc->cq, ret);
 141                 if (ret != len)
 142                         return 1;
 143                 cq_dequeue(hc->cq);
 144         }
 145         return 1;
 146 }
 147
 148 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 149         size_t sent)
 150 {
 151         int ret = cq_enqueue(hc->cq, chunk_num, sent);
 152         if (ret < 0)
 153                 http_shutdown_client(hc, "queue error");
 154         return ret;
 155 }
 156
 157 static void http_send( long unsigned current_chunk,
 158         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 159 {
 160         struct http_client *hc, *tmp;
 161         int ret;
 162
 163         list_for_each_entry_safe(hc, tmp, &clients, node) {
 164                 if (hc->status != HTTP_STREAMING &&
 165                                 hc->status != HTTP_READY_TO_STREAM)
 166                         continue;
 167                 if (hc->status == HTTP_READY_TO_STREAM) {
 168                         size_t hlen;
 169                         char *hbuf = vss_get_header(&hlen);
 170                         if (hbuf && hlen > 0 && current_chunk) {
 171                                 /* need to send header */
 172                                 PARA_INFO_LOG("queueing header: %zu\n", hlen);
 173                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 174                                         continue;
 175                         } else
 176                                 PARA_INFO_LOG("no need to queue header\n");
 177                         hc->status = HTTP_STREAMING;
 178                 }
 179                 ret = send_queued_chunks(hc);
 180                 if (ret < 0) {
 181                         http_shutdown_client(hc, "queue send error");
 182                         continue;
 183                 }
 184                 if (!len)
 185                         continue;
 186                 if (!ret || write_ok(hc->fd) <= 0) {
 187                         queue_chunk_or_shutdown(hc, current_chunk, 0);
 188                         continue;
 189                 }
 190 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, CLIENT_ADDR(hc));
 191                 ret = write(hc->fd, buf, len);
 192 //              PARA_DEBUG_LOG("ret: %d\n", ret);
 193                 if (ret < 0) {
 194                         http_shutdown_client(hc, "send error");
 195                         continue;
 196                 }
 197                 if (ret != len)
 198                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 199         }
 200 }
 201
 202 static int host_in_access_perm_list(struct http_client *hc)
 203 {
 204         struct access_info *ai, *tmp;
 205         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 206                 unsigned mask = ((~0U) >> ai->netmask);
 207                 if ((hc->addr.sin_addr.s_addr & mask) == (ai->addr.s_addr & mask))
 208                         return 1;
 209         }
 210         return 0;
 211 }
 212
 213 static void http_post_select(fd_set *rfds, fd_set *wfds)
 214 {
 215         int i = -1, match;
 216         struct http_client *hc, *tmp;
 217         const char *err_msg;
 218
 219         list_for_each_entry_safe(hc, tmp, &clients, node) {
 220                 i++;
 221 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, CLIENT_ADDR(hc));
 222                 switch (hc->status) {
 223                 case HTTP_STREAMING: /* nothing to do */
 224                 case HTTP_READY_TO_STREAM:
 225                         break;
 226                 case HTTP_CONNECTED: /* need to recv get request */
 227                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 228                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 229                                                 < 0) {
 230                                         hc->status = HTTP_INVALID_GET_REQUEST;
 231                                 } else {
 232                                         hc->status = HTTP_GOT_GET_REQUEST;
 233                                         PARA_INFO_LOG("%s",
 234                                                 "received get request\n");
 235                                 }
 236                         }
 237                         break;
 238                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 239                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 240                                 hc->status = HTTP_SENT_OK_MSG;
 241                                 http_send_ok_msg(hc);
 242                         }
 243                         break;
 244                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 245                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 246                                 if (http_send_err_msg(hc) >= 0)
 247                                         http_shutdown_client(hc,
 248                                                 "invalid get request");
 249                         }
 250                         break;
 251                 case HTTP_SENT_OK_MSG: /* need to send header? */
 252                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 253                                 hc->status = HTTP_READY_TO_STREAM;
 254                         break;
 255                 }
 256         }
 257         if (!FD_ISSET(server_fd, rfds))
 258                 return;
 259         hc = para_calloc(sizeof(struct http_client));
 260         err_msg = "accept error";
 261         hc->fd = para_accept(server_fd, &hc->addr, sizeof(struct sockaddr_in));
 262         if (hc->fd <= 0)
 263                 goto err_out;
 264         PARA_NOTICE_LOG("connection from %s (fd %d)\n", CLIENT_ADDR(hc), hc->fd);
 265         if (conf.http_max_clients_arg > 0 && numclients >=
 266                         conf.http_max_clients_arg) {
 267                 err_msg = "server full";
 268                 goto err_out;
 269         }
 270         match = host_in_access_perm_list(hc);
 271         PARA_DEBUG_LOG("host_in_access_perm_list: %d\n", match);
 272         if ((match && !conf.http_default_deny_given) ||
 273                         (!match && conf.http_default_deny_given)) {
 274                 err_msg = "permission denied";
 275                 goto err_out;
 276         }
 277         hc->status = HTTP_CONNECTED;
 278         hc->cq = cq_new(MAX_BACKLOG);
 279         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 280                 CLIENT_ADDR(hc), hc->fd);
 281         numclients++;
 282         para_list_add(&hc->node, &clients);
 283         add_close_on_fork_list(hc->fd);
 284         mark_fd_nonblock(hc->fd);
 285         return;
 286 err_out:
 287         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 288                 CLIENT_ADDR(hc), err_msg);
 289         if (hc->fd > 0)
 290                 close(hc->fd);
 291         free(hc);
 292 }
 293
 294 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 295 {
 296         struct http_client *hc, *tmp;
 297
 298         if (server_fd < 0)
 299                 return;
 300         para_fd_set(server_fd, rfds, max_fileno);
 301         list_for_each_entry_safe(hc, tmp, &clients, node) {
 302                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 303                 hc->check_r = 0;
 304                 hc->check_w = 0;
 305                 switch (hc->status) {
 306                 case HTTP_STREAMING:
 307                 case HTTP_READY_TO_STREAM:
 308                         break;
 309                 case HTTP_CONNECTED: /* need to recv get request */
 310                         para_fd_set(hc->fd, rfds, max_fileno);
 311                         hc->check_r = 1;
 312                         break;
 313                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 314                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 315                         para_fd_set(hc->fd, wfds, max_fileno);
 316                         hc->check_w = 1;
 317                         break;
 318                 case HTTP_SENT_OK_MSG:
 319                         if (!vss_playing())
 320                                 break; /* wait until server starts playing */
 321                         para_fd_set(hc->fd, wfds, max_fileno);
 322                         hc->check_w = 1;
 323                         break;
 324                 }
 325         }
 326 }
 327
 328 static int open_tcp_port(int port)
 329 {
 330         int ret;
 331
 332         server_fd = init_tcp_socket(port);
 333         if (server_fd < 0) {
 334                 http_shutdown_clients();
 335                 self->status = SENDER_OFF;
 336                 return server_fd;
 337         }
 338         ret = mark_fd_nonblock(server_fd);
 339         if (ret < 0) {
 340                 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
 341                 exit(EXIT_FAILURE);
 342         }
 343         self->status = SENDER_ON;
 344         add_close_on_fork_list(server_fd);
 345         return 1;
 346 }
 347
 348 static int http_com_on(__a_unused struct sender_command_data *scd)
 349 {
 350         if (self->status == SENDER_ON)
 351                 return 1;
 352         return open_tcp_port(conf.http_port_arg);
 353 }
 354
 355 static int http_com_off(__a_unused struct sender_command_data *scd)
 356 {
 357         self->status = SENDER_OFF;
 358         if (server_fd > 0) {
 359                 close(server_fd);
 360                 del_close_on_fork_list(server_fd);
 361                 server_fd = -1;
 362         }
 363         http_shutdown_clients();
 364         return 1;
 365 }
 366
 367 static void del_perm_list_entry(struct sender_command_data *scd)
 368 {
 369         struct access_info *ai, *tmp;
 370
 371         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 372                 char *nad = para_strdup(inet_ntoa(ai->addr));
 373                 if (!strcmp(nad, inet_ntoa(scd->addr)) &&
 374                                 ai->netmask == scd->netmask) {
 375                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 376                                 nad, ai->netmask);
 377                         list_del(&ai->node);
 378                         free(ai);
 379                 }
 380                 free(nad);
 381         }
 382 }
 383
 384 static void add_perm_list_entry(struct sender_command_data *scd)
 385 {
 386         struct access_info *ai = para_malloc(sizeof(struct access_info));
 387         ai->addr = scd->addr;
 388         ai->netmask = scd->netmask;
 389         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 390                 ai->netmask);
 391         para_list_add(&ai->node, &access_perm_list);
 392 }
 393
 394 static int http_com_deny(struct sender_command_data *scd)
 395 {
 396         if (conf.http_default_deny_given)
 397                 del_perm_list_entry(scd);
 398         else
 399                 add_perm_list_entry(scd);
 400         return 1;
 401 }
 402
 403 static int http_com_allow(struct sender_command_data *scd)
 404 {
 405         if (conf.http_default_deny_given)
 406                 add_perm_list_entry(scd);
 407         else
 408                 del_perm_list_entry(scd);
 409         return 1;
 410 }
 411
 412 static char *http_info(void)
 413 {
 414         char *clnts = NULL, *ap = NULL, *ret;
 415         struct access_info *ai, *tmp_ai;
 416         struct http_client *hc, *tmp_hc;
 417
 418         list_for_each_entry_safe(ai, tmp_ai, &access_perm_list, node) {
 419                 char *tmp = make_message("%s%s/%d ", ap? ap : "",
 420                         inet_ntoa(ai->addr), ai->netmask);
 421                 free(ap);
 422                 ap = tmp;
 423         }
 424         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 425                 char *tmp = make_message("%s%s:%d ", clnts? clnts : "",
 426                         CLIENT_ADDR(hc), CLIENT_PORT(hc));
 427                 free(clnts);
 428                 clnts = tmp;
 429         }
 430         ret = make_message(
 431                 "http status: %s\n"
 432                 "http tcp port: %d\n"
 433                 "http clients: %d\n"
 434                 "http maximal number of clients: %d%s\n"
 435                 "http connected clients: %s\n"
 436                 "http access %s list: %s\n",
 437                 (self->status == SENDER_ON)? "on" : "off",
 438                 conf.http_port_arg,
 439                 numclients,
 440                 conf.http_max_clients_arg,
 441                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 442                 clnts? clnts : "(none)",
 443                 conf.http_default_deny_given? "allow" : "deny",
 444                 ap? ap : "(none)"
 445         );
 446         free(ap);
 447         free(clnts);
 448         return ret;
 449 }
 450
 451 static void init_access_control_list(void)
 452 {
 453         int i;
 454         struct sender_command_data scd;
 455
 456         INIT_LIST_HEAD(&access_perm_list);
 457         for (i = 0; i < conf.http_access_given; i++) {
 458                 char *arg = para_strdup(conf.http_access_arg[i]);
 459                 char *p = strchr(arg, '/');
 460                 if (!p)
 461                         goto err;
 462                 *p = '\0';
 463                 if (!inet_aton(arg, &scd.addr))
 464                         goto err;
 465                 scd.netmask = atoi(++p);
 466                 if (scd.netmask < 0 || scd.netmask > 32)
 467                         goto err;
 468                 add_perm_list_entry(&scd);
 469                 goto success;
 470 err:
 471                 PARA_CRIT_LOG("syntax error for http_access option "
 472                         "#%d, ignoring\n", i);
 473 success:
 474                 free(arg);
 475                 continue;
 476         }
 477 }
 478
 479 static char *http_help(void)
 480 {
 481         return make_message(
 482                 "usage: {on|off}\n"
 483                 "usage: {allow|deny} IP mask\n"
 484                 "example: allow 127.0.0.1 32\n"
 485         );
 486 }
 487
 488 /**
 489  * The init function of the http sender.
 490  *
 491  * \param s Pointer to the http sender struct.
 492  *
 493  * It initializes all function pointers of \a s, the client list and the access
 494  * control list. If the autostart option was given, the tcp port is opened.
 495  */
 496 void http_send_init(struct sender *s)
 497 {
 498         INIT_LIST_HEAD(&clients);
 499         s->info = http_info;
 500         s->send = http_send;
 501         s->pre_select = http_pre_select;
 502         s->post_select = http_post_select;
 503         s->shutdown_clients = http_shutdown_clients;
 504         s->help = http_help;
 505         s->client_cmds[SENDER_ON] = http_com_on;
 506         s->client_cmds[SENDER_OFF] = http_com_off;
 507         s->client_cmds[SENDER_DENY] = http_com_deny;
 508         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 509         s->client_cmds[SENDER_ADD] = NULL;
 510         s->client_cmds[SENDER_DELETE] = NULL;
 511         self = s;
 512         init_access_control_list();
 513         if (!conf.http_no_autostart_given)
 514                 open_tcp_port(conf.http_port_arg); /* ignore errors */
 515         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 516 }