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 #include <sys/types.h>
  10 #include <dirent.h>
  11
  12 #include "para.h"
  13 #include "error.h"
  14 #include "string.h"
  15 #include "server.cmdline.h"
  16 #include "afh.h"
  17 #include "afs.h"
  18 #include "server.h"
  19 #include "http.h"
  20 #include "vss.h"
  21 #include "send.h"
  22 #include "list.h"
  23 #include "close_on_fork.h"
  24 #include "net.h"
  25 #include "fd.h"
  26 #include "chunk_queue.h"
  27
  28 #define HTTP_ERR_MSG "HTTP/1.0 400 Bad Request\n"
  29 /** \endcond */
  30
  31 /** The possible states of a client from the server's POV. */
  32 enum http_status {
  33         /** We accepted the connection on the tcp socket. */
  34         HTTP_CONNECTED,
  35         /** Successfully received the get request. */
  36         HTTP_GOT_GET_REQUEST,
  37         /** We sent the OK message back to the client. */
  38         HTTP_SENT_OK_MSG,
  39         /** Connection established, we might need to send the audio file header. */
  40         HTTP_READY_TO_STREAM,
  41         /** Connection is ready for sending audio data. */
  42         HTTP_STREAMING,
  43         /** We didn't receive a valid get request. */
  44         HTTP_INVALID_GET_REQUEST
  45 };
  46
  47 /** Clients will be kicked if there are more than that many bytes pending. */
  48 #define MAX_BACKLOG 400000
  49 /** The list of connected clients. */
  50 static struct list_head clients;
  51 /** The whitelist/blacklist. */
  52 static struct list_head access_perm_list;
  53
  54 /** Describes one client that connected the tcp port of the http sender. */
  55 struct http_client {
  56         /** The file descriptor of the client. */
  57         int fd;
  58         /** The socket `name' of the client. */
  59         char *name;
  60         /** The client's current status. */
  61         enum http_status status;
  62         /** Non-zero if we included \a fd in the read set.*/
  63         int check_r;
  64         /** Non-zero if we included \a fd in the write set. */
  65         int check_w;
  66         /** The position of this client in the client list. */
  67         struct list_head node;
  68         /** The list of pending chunks for this client. */
  69         struct chunk_queue *cq;
  70 };
  71
  72 /**
  73  * Describes one entry in the blacklist/whitelist of the http sender.
  74  */
  75 struct access_info {
  76         /** The address to be black/whitelisted. */
  77         struct in_addr addr;
  78         /** The netmask for this entry. */
  79         unsigned netmask;
  80         /** The position of this entry in the access_perm_list. */
  81         struct list_head node;
  82 };
  83
  84 static int server_fd = -1, numclients;
  85 static struct sender *self;
  86
  87
  88 static void http_shutdown_client(struct http_client *hc, const char *msg)
  89 {
  90         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", hc->name, hc->fd,
  91                 msg);
  92         numclients--;
  93         free(hc->name);
  94         close(hc->fd);
  95         del_close_on_fork_list(hc->fd);
  96         cq_destroy(hc->cq);
  97         list_del(&hc->node);
  98         free(hc);
  99 }
 100
 101 static void http_shutdown_clients(void)
 102 {
 103         struct http_client *hc, *tmp;
 104         list_for_each_entry_safe(hc, tmp, &clients, node)
 105                 http_shutdown_client(hc, "vss request");
 106 }
 107
 108 static int http_send_msg(struct http_client *hc, const char *msg)
 109 {
 110         int ret = send_buffer(hc->fd, msg);
 111
 112         if (ret < 0)
 113                 http_shutdown_client(hc, "send msg failed");
 114         return ret;
 115 }
 116
 117 static void http_send_ok_msg(struct http_client *hc)
 118 {
 119         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 120         http_send_msg(hc, HTTP_OK_MSG);
 121 }
 122
 123 static int http_send_err_msg(struct http_client *hc)
 124 {
 125         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 126         return http_send_msg(hc, HTTP_ERR_MSG);
 127 }
 128
 129 static int send_queued_chunks(struct http_client *hc)
 130 {
 131         struct queued_chunk *qc;
 132         while ((qc = cq_peek(hc->cq))) {
 133                 char *buf;
 134                 size_t len;
 135                 int ret = write_ok(hc->fd);
 136                 if (ret <= 0)
 137                         return ret? -E_WRITE_OK : 0;
 138                 cq_get(qc, &buf, &len);
 139                 ret = write(hc->fd, buf, len);
 140                 if (ret < 0)
 141                         return -E_SEND_QUEUED_CHUNK;
 142                 cq_update(hc->cq, ret);
 143                 if (ret != len)
 144                         return 1;
 145                 cq_dequeue(hc->cq);
 146         }
 147         return 1;
 148 }
 149
 150 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 151         size_t sent)
 152 {
 153         int ret = cq_enqueue(hc->cq, chunk_num, sent);
 154         if (ret < 0)
 155                 http_shutdown_client(hc, "queue error");
 156         return ret;
 157 }
 158
 159 static void http_send( long unsigned current_chunk,
 160         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 161 {
 162         struct http_client *hc, *tmp;
 163         int ret;
 164
 165         list_for_each_entry_safe(hc, tmp, &clients, node) {
 166                 if (hc->status != HTTP_STREAMING &&
 167                                 hc->status != HTTP_READY_TO_STREAM)
 168                         continue;
 169                 if (hc->status == HTTP_READY_TO_STREAM) {
 170                         size_t hlen;
 171                         char *hbuf = vss_get_header(&hlen);
 172                         if (hbuf && hlen > 0 && current_chunk) {
 173                                 /* need to send header */
 174                                 PARA_INFO_LOG("queueing header: %zu\n", hlen);
 175                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 176                                         continue;
 177                         } else
 178                                 PARA_INFO_LOG("no need to queue header\n");
 179                         hc->status = HTTP_STREAMING;
 180                 }
 181                 ret = send_queued_chunks(hc);
 182                 if (ret < 0) {
 183                         http_shutdown_client(hc, "queue send error");
 184                         continue;
 185                 }
 186                 if (!len)
 187                         continue;
 188                 if (!ret || write_ok(hc->fd) <= 0) {
 189                         queue_chunk_or_shutdown(hc, current_chunk, 0);
 190                         continue;
 191                 }
 192 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, remote_name(hc->fd));
 193                 ret = write(hc->fd, buf, len);
 194 //              PARA_DEBUG_LOG("ret: %d\n", ret);
 195                 if (ret < 0) {
 196                         http_shutdown_client(hc, "send error");
 197                         continue;
 198                 }
 199                 if (ret != len)
 200                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 201         }
 202 }
 203
 204 static int host_in_access_perm_list(struct http_client *hc)
 205 {
 206         struct sockaddr_storage   ss;
 207         socklen_t                 sslen = sizeof(ss);
 208
 209         if (getpeername(hc->fd, (struct sockaddr *)&ss, &sslen) < 0) {
 210                 PARA_ERROR_LOG("can not determine address family: %s\n", strerror(errno));
 211         } else if (ss.ss_family == AF_INET) {
 212                 /* FIXME: access restriction is (currently) only supported for IPv4 */
 213                 struct access_info *ai, *tmp;
 214                 struct in_addr client_addr = ((struct sockaddr_in *)&ss)->sin_addr;
 215
 216                 list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 217                         unsigned mask = ((~0U) >> ai->netmask);
 218                         if ((client_addr.s_addr & mask) == (ai->addr.s_addr & mask))
 219                                 return 1;
 220                 }
 221         }
 222         return 0;
 223 }
 224
 225 static void http_post_select(fd_set *rfds, fd_set *wfds)
 226 {
 227         int i = -1, match;
 228         struct http_client *hc, *tmp;
 229         const char *err_msg;
 230
 231         list_for_each_entry_safe(hc, tmp, &clients, node) {
 232                 i++;
 233 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, remote_name(hc->fd));
 234                 switch (hc->status) {
 235                 case HTTP_STREAMING: /* nothing to do */
 236                 case HTTP_READY_TO_STREAM:
 237                         break;
 238                 case HTTP_CONNECTED: /* need to recv get request */
 239                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 240                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 241                                                 < 0) {
 242                                         hc->status = HTTP_INVALID_GET_REQUEST;
 243                                 } else {
 244                                         hc->status = HTTP_GOT_GET_REQUEST;
 245                                         PARA_INFO_LOG("%s",
 246                                                 "received get request\n");
 247                                 }
 248                         }
 249                         break;
 250                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 251                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 252                                 hc->status = HTTP_SENT_OK_MSG;
 253                                 http_send_ok_msg(hc);
 254                         }
 255                         break;
 256                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 257                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 258                                 if (http_send_err_msg(hc) >= 0)
 259                                         http_shutdown_client(hc,
 260                                                 "invalid get request");
 261                         }
 262                         break;
 263                 case HTTP_SENT_OK_MSG: /* need to send header? */
 264                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 265                                 hc->status = HTTP_READY_TO_STREAM;
 266                         break;
 267                 }
 268         }
 269         if (!FD_ISSET(server_fd, rfds))
 270                 return;
 271         hc = para_calloc(sizeof(struct http_client));
 272         err_msg = "accept error";
 273         hc->fd = para_accept(server_fd, NULL, 0);
 274         if (hc->fd <= 0)
 275                 goto err_out;
 276         hc->name = make_message("%s", remote_name(hc->fd));
 277         PARA_NOTICE_LOG("connection from %s (fd %d)\n", hc->name, hc->fd);
 278         if (conf.http_max_clients_arg > 0 && numclients >=
 279                         conf.http_max_clients_arg) {
 280                 err_msg = "server full";
 281                 goto err_out;
 282         }
 283         match = host_in_access_perm_list(hc);
 284         PARA_DEBUG_LOG("host_in_access_perm_list: %d\n", match);
 285         if ((match && !conf.http_default_deny_given) ||
 286                         (!match && conf.http_default_deny_given)) {
 287                 err_msg = "permission denied";
 288                 goto err_out;
 289         }
 290         hc->status = HTTP_CONNECTED;
 291         hc->cq = cq_new(MAX_BACKLOG);
 292         numclients++;
 293         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 294                 hc->name, hc->fd);
 295         para_list_add(&hc->node, &clients);
 296         add_close_on_fork_list(hc->fd);
 297         mark_fd_nonblocking(hc->fd);
 298         return;
 299 err_out:
 300         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 301                 hc->name, err_msg);
 302         if (hc->fd > 0)
 303                 close(hc->fd);
 304         free(hc);
 305 }
 306
 307 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 308 {
 309         struct http_client *hc, *tmp;
 310
 311         if (server_fd < 0)
 312                 return;
 313         para_fd_set(server_fd, rfds, max_fileno);
 314         list_for_each_entry_safe(hc, tmp, &clients, node) {
 315                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 316                 hc->check_r = 0;
 317                 hc->check_w = 0;
 318                 switch (hc->status) {
 319                 case HTTP_STREAMING:
 320                 case HTTP_READY_TO_STREAM:
 321                         break;
 322                 case HTTP_CONNECTED: /* need to recv get request */
 323                         para_fd_set(hc->fd, rfds, max_fileno);
 324                         hc->check_r = 1;
 325                         break;
 326                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 327                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 328                         para_fd_set(hc->fd, wfds, max_fileno);
 329                         hc->check_w = 1;
 330                         break;
 331                 case HTTP_SENT_OK_MSG:
 332                         if (!vss_playing())
 333                                 break; /* wait until server starts playing */
 334                         para_fd_set(hc->fd, wfds, max_fileno);
 335                         hc->check_w = 1;
 336                         break;
 337                 }
 338         }
 339 }
 340
 341 static int open_tcp_port(int port)
 342 {
 343         int ret;
 344
 345         server_fd = para_listen(AF_UNSPEC, IPPROTO_TCP, port);
 346         if (server_fd < 0) {
 347                 http_shutdown_clients();
 348                 self->status = SENDER_OFF;
 349                 return server_fd;
 350         }
 351         ret = mark_fd_nonblocking(server_fd);
 352         if (ret < 0) {
 353                 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
 354                 exit(EXIT_FAILURE);
 355         }
 356         self->status = SENDER_ON;
 357         add_close_on_fork_list(server_fd);
 358         return 1;
 359 }
 360
 361 static int http_com_on(__a_unused struct sender_command_data *scd)
 362 {
 363         if (self->status == SENDER_ON)
 364                 return 1;
 365         return open_tcp_port(conf.http_port_arg);
 366 }
 367
 368 static int http_com_off(__a_unused struct sender_command_data *scd)
 369 {
 370         self->status = SENDER_OFF;
 371         if (server_fd > 0) {
 372                 close(server_fd);
 373                 del_close_on_fork_list(server_fd);
 374                 server_fd = -1;
 375         }
 376         http_shutdown_clients();
 377         return 1;
 378 }
 379
 380 static void del_perm_list_entry(struct sender_command_data *scd)
 381 {
 382         struct access_info *ai, *tmp;
 383
 384         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 385                 char *nad = para_strdup(inet_ntoa(ai->addr));
 386                 if (!strcmp(nad, inet_ntoa(scd->addr)) &&
 387                                 ai->netmask == scd->netmask) {
 388                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 389                                 nad, ai->netmask);
 390                         list_del(&ai->node);
 391                         free(ai);
 392                 }
 393                 free(nad);
 394         }
 395 }
 396
 397 static void add_perm_list_entry(struct sender_command_data *scd)
 398 {
 399         struct access_info *ai = para_malloc(sizeof(struct access_info));
 400         ai->addr = scd->addr;
 401         ai->netmask = scd->netmask;
 402         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 403                 ai->netmask);
 404         para_list_add(&ai->node, &access_perm_list);
 405 }
 406
 407 static int http_com_deny(struct sender_command_data *scd)
 408 {
 409         if (conf.http_default_deny_given)
 410                 del_perm_list_entry(scd);
 411         else
 412                 add_perm_list_entry(scd);
 413         return 1;
 414 }
 415
 416 static int http_com_allow(struct sender_command_data *scd)
 417 {
 418         if (conf.http_default_deny_given)
 419                 add_perm_list_entry(scd);
 420         else
 421                 del_perm_list_entry(scd);
 422         return 1;
 423 }
 424
 425 static char *http_info(void)
 426 {
 427         char *clnts = NULL, *ap = NULL, *ret;
 428         struct access_info *ai, *tmp_ai;
 429         struct http_client *hc, *tmp_hc;
 430
 431         list_for_each_entry_safe(ai, tmp_ai, &access_perm_list, node) {
 432                 char *tmp = make_message("%s%s/%d ", ap? ap : "",
 433                         inet_ntoa(ai->addr), ai->netmask);
 434                 free(ap);
 435                 ap = tmp;
 436         }
 437         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 438                 char *tmp = make_message("%s%s ", clnts? clnts : "", hc->name);
 439                 free(clnts);
 440                 clnts = tmp;
 441         }
 442         ret = make_message(
 443                 "http status: %s\n"
 444                 "http tcp port: %d\n"
 445                 "http clients: %d\n"
 446                 "http maximal number of clients: %d%s\n"
 447                 "http connected clients: %s\n"
 448                 "http access %s list: %s\n",
 449                 (self->status == SENDER_ON)? "on" : "off",
 450                 conf.http_port_arg,
 451                 numclients,
 452                 conf.http_max_clients_arg,
 453                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 454                 clnts? clnts : "(none)",
 455                 conf.http_default_deny_given? "allow" : "deny",
 456                 ap? ap : "(none)"
 457         );
 458         free(ap);
 459         free(clnts);
 460         return ret;
 461 }
 462
 463 static void init_access_control_list(void)
 464 {
 465         int i;
 466         struct sender_command_data scd;
 467
 468         INIT_LIST_HEAD(&access_perm_list);
 469         for (i = 0; i < conf.http_access_given; i++) {
 470                 char *arg = para_strdup(conf.http_access_arg[i]);
 471                 char *p = strchr(arg, '/');
 472                 if (!p)
 473                         goto err;
 474                 *p = '\0';
 475                 if (!inet_pton(AF_INET, arg, &scd.addr))
 476                         goto err;
 477                 scd.netmask = atoi(++p);
 478                 if (scd.netmask < 0 || scd.netmask > 32)
 479                         goto err;
 480                 add_perm_list_entry(&scd);
 481                 goto success;
 482 err:
 483                 PARA_CRIT_LOG("syntax error for http_access option "
 484                         "#%d, ignoring\n", i);
 485 success:
 486                 free(arg);
 487                 continue;
 488         }
 489 }
 490
 491 static char *http_help(void)
 492 {
 493         return make_message(
 494                 "usage: {on|off}\n"
 495                 "usage: {allow|deny} IP mask\n"
 496                 "example: allow 127.0.0.1 32\n"
 497         );
 498 }
 499
 500 /**
 501  * The init function of the http sender.
 502  *
 503  * \param s Pointer to the http sender struct.
 504  *
 505  * It initializes all function pointers of \a s, the client list and the access
 506  * control list. If the autostart option was given, the tcp port is opened.
 507  */
 508 void http_send_init(struct sender *s)
 509 {
 510         INIT_LIST_HEAD(&clients);
 511         s->info = http_info;
 512         s->send = http_send;
 513         s->pre_select = http_pre_select;
 514         s->post_select = http_post_select;
 515         s->shutdown_clients = http_shutdown_clients;
 516         s->help = http_help;
 517         s->client_cmds[SENDER_ON] = http_com_on;
 518         s->client_cmds[SENDER_OFF] = http_com_off;
 519         s->client_cmds[SENDER_DENY] = http_com_deny;
 520         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 521         s->client_cmds[SENDER_ADD] = NULL;
 522         s->client_cmds[SENDER_DELETE] = NULL;
 523         self = s;
 524         init_access_control_list();
 525         if (!conf.http_no_autostart_given)
 526                 open_tcp_port(conf.http_port_arg); /* ignore errors */
 527         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 528 }