http_send.c

   1 /*
   2  * Copyright (C) 2005-2008 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 /** Message sent to clients that do not send a valid get request. */
  29 #define HTTP_ERR_MSG "HTTP/1.0 400 Bad Request\n"
  30
  31
  32 /** The possible states of a client from the server's POV. */
  33 enum http_status {
  34         /** We accepted the connection on the tcp socket. */
  35         HTTP_CONNECTED,
  36         /** Successfully received the get request. */
  37         HTTP_GOT_GET_REQUEST,
  38         /** We sent the OK message back to the client. */
  39         HTTP_SENT_OK_MSG,
  40         /** Connection established, we might need to send the audio file header. */
  41         HTTP_READY_TO_STREAM,
  42         /** Connection is ready for sending audio data. */
  43         HTTP_STREAMING,
  44         /** We didn't receive a valid get request. */
  45         HTTP_INVALID_GET_REQUEST
  46 };
  47
  48 /** Clients will be kicked if there are more than that many bytes pending. */
  49 #define MAX_BACKLOG 400000
  50 /** The list of connected clients. */
  51 static struct list_head clients;
  52 /** The whitelist/blacklist. */
  53 static struct list_head http_acl;
  54
  55 /** Describes one client that connected the tcp port of the http sender. */
  56 struct http_client {
  57         /** The file descriptor of the client. */
  58         int fd;
  59         /** The socket `name' of the client. */
  60         char *name;
  61         /** The client's current status. */
  62         enum http_status status;
  63         /** Non-zero if we included \a fd in the read set.*/
  64         int check_r;
  65         /** Non-zero if we included \a fd in the write set. */
  66         int check_w;
  67         /** The position of this client in the client list. */
  68         struct list_head node;
  69         /** The list of pending chunks for this client. */
  70         struct chunk_queue *cq;
  71 };
  72
  73 /**
  74  * Describes one entry in the blacklist/whitelist of the http sender.
  75  */
  76 struct access_info {
  77         /** The address to be black/whitelisted. */
  78         struct in_addr addr;
  79         /** The netmask for this entry. */
  80         unsigned netmask;
  81         /** The position of this entry in the acl. */
  82         struct list_head node;
  83 };
  84
  85 static int server_fd = -1, numclients;
  86 static struct sender *self;
  87
  88
  89 static void http_shutdown_client(struct http_client *hc, const char *msg)
  90 {
  91         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", hc->name, hc->fd,
  92                 msg);
  93         numclients--;
  94         free(hc->name);
  95         close(hc->fd);
  96         del_close_on_fork_list(hc->fd);
  97         cq_destroy(hc->cq);
  98         list_del(&hc->node);
  99         free(hc);
 100 }
 101
 102 static void http_shutdown_clients(void)
 103 {
 104         struct http_client *hc, *tmp;
 105         list_for_each_entry_safe(hc, tmp, &clients, node)
 106                 http_shutdown_client(hc, "vss request");
 107 }
 108
 109 static int http_send_msg(struct http_client *hc, const char *msg)
 110 {
 111         int ret = send_buffer(hc->fd, msg);
 112
 113         if (ret < 0)
 114                 http_shutdown_client(hc, "send msg failed");
 115         return ret;
 116 }
 117
 118 static void http_send_ok_msg(struct http_client *hc)
 119 {
 120         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 121         http_send_msg(hc, HTTP_OK_MSG);
 122 }
 123
 124 static int http_send_err_msg(struct http_client *hc)
 125 {
 126         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 127         return http_send_msg(hc, HTTP_ERR_MSG);
 128 }
 129
 130 static int send_queued_chunks(struct http_client *hc)
 131 {
 132         struct queued_chunk *qc;
 133         while ((qc = cq_peek(hc->cq))) {
 134                 char *buf;
 135                 size_t len;
 136                 int ret = write_ok(hc->fd);
 137                 if (ret <= 0)
 138                         return ret? -E_WRITE_OK : 0;
 139                 cq_get(qc, &buf, &len);
 140                 ret = write(hc->fd, buf, len);
 141                 if (ret < 0)
 142                         return -E_SEND_QUEUED_CHUNK;
 143                 cq_update(hc->cq, ret);
 144                 if (ret != len)
 145                         return 1;
 146                 cq_dequeue(hc->cq);
 147         }
 148         return 1;
 149 }
 150
 151 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 152         size_t sent)
 153 {
 154         int ret = cq_enqueue(hc->cq, chunk_num, sent);
 155         if (ret < 0)
 156                 http_shutdown_client(hc, "queue error");
 157         return ret;
 158 }
 159
 160 static void http_send( long unsigned current_chunk,
 161         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 162 {
 163         struct http_client *hc, *tmp;
 164         int ret;
 165
 166         list_for_each_entry_safe(hc, tmp, &clients, node) {
 167                 if (hc->status != HTTP_STREAMING &&
 168                                 hc->status != HTTP_READY_TO_STREAM)
 169                         continue;
 170                 if (hc->status == HTTP_READY_TO_STREAM) {
 171                         size_t hlen;
 172                         char *hbuf = vss_get_header(&hlen);
 173                         if (hbuf && hlen > 0 && current_chunk) {
 174                                 /* need to send header */
 175                                 PARA_INFO_LOG("queueing header: %zu\n", hlen);
 176                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 177                                         continue;
 178                         } else
 179                                 PARA_INFO_LOG("no need to queue header\n");
 180                         hc->status = HTTP_STREAMING;
 181                 }
 182                 ret = send_queued_chunks(hc);
 183                 if (ret < 0) {
 184                         http_shutdown_client(hc, "queue send error");
 185                         continue;
 186                 }
 187                 if (!len)
 188                         continue;
 189                 if (!ret || write_ok(hc->fd) <= 0) {
 190                         queue_chunk_or_shutdown(hc, current_chunk, 0);
 191                         continue;
 192                 }
 193 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, remote_name(hc->fd));
 194                 ret = write(hc->fd, buf, len);
 195 //              PARA_DEBUG_LOG("ret: %d\n", ret);
 196                 if (ret < 0) {
 197                         http_shutdown_client(hc, "send error");
 198                         continue;
 199                 }
 200                 if (ret != len)
 201                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 202         }
 203 }
 204
 205 /**
 206  * Return true if addr_1 matches addr_2 in the first `netmask' bits.
 207  */
 208 static int v4_addr_match(uint32_t addr_1, uint32_t addr_2, uint8_t netmask)
 209 {
 210         uint32_t mask = ~0U;
 211
 212         if (netmask < 32)
 213                 mask <<= (32 - netmask);
 214         return (htonl(addr_1) & mask) == (htonl(addr_2) & mask);
 215 }
 216
 217 static int host_in_acl(int fd, struct list_head *acl)
 218 {
 219         struct access_info *ai, *tmp;
 220         struct sockaddr_storage ss;
 221         socklen_t sslen = sizeof(ss);
 222         struct in_addr v4_addr;
 223
 224         if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) {
 225                 PARA_ERROR_LOG("Can not determine peer address: %s\n", strerror(errno));
 226                 goto no_match;
 227         }
 228         v4_addr = extract_v4_addr(&ss);
 229         if (!v4_addr.s_addr)
 230                 goto no_match;
 231
 232         list_for_each_entry_safe(ai, tmp, acl, node)
 233                 if (v4_addr_match(v4_addr.s_addr, ai->addr.s_addr, ai->netmask))
 234                         return 1;
 235 no_match:
 236         return 0;
 237 }
 238
 239 static void http_post_select(fd_set *rfds, fd_set *wfds)
 240 {
 241         int i = -1, match;
 242         struct http_client *hc, *tmp;
 243         const char *err_msg;
 244
 245         list_for_each_entry_safe(hc, tmp, &clients, node) {
 246                 i++;
 247 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, remote_name(hc->fd));
 248                 switch (hc->status) {
 249                 case HTTP_STREAMING: /* nothing to do */
 250                 case HTTP_READY_TO_STREAM:
 251                         break;
 252                 case HTTP_CONNECTED: /* need to recv get request */
 253                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 254                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 255                                                 < 0) {
 256                                         hc->status = HTTP_INVALID_GET_REQUEST;
 257                                 } else {
 258                                         hc->status = HTTP_GOT_GET_REQUEST;
 259                                         PARA_INFO_LOG("%s",
 260                                                 "received get request\n");
 261                                 }
 262                         }
 263                         break;
 264                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 265                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 266                                 hc->status = HTTP_SENT_OK_MSG;
 267                                 http_send_ok_msg(hc);
 268                         }
 269                         break;
 270                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 271                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 272                                 if (http_send_err_msg(hc) >= 0)
 273                                         http_shutdown_client(hc,
 274                                                 "invalid get request");
 275                         }
 276                         break;
 277                 case HTTP_SENT_OK_MSG: /* need to send header? */
 278                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 279                                 hc->status = HTTP_READY_TO_STREAM;
 280                         break;
 281                 }
 282         }
 283         if (!FD_ISSET(server_fd, rfds))
 284                 return;
 285         hc = para_calloc(sizeof(struct http_client));
 286         err_msg = "accept error";
 287         hc->fd = para_accept(server_fd, NULL, 0);
 288         if (hc->fd <= 0)
 289                 goto err_out;
 290         hc->name = make_message("%s", remote_name(hc->fd));
 291         PARA_NOTICE_LOG("connection from %s (fd %d)\n", hc->name, hc->fd);
 292         if (conf.http_max_clients_arg > 0 && numclients >=
 293                         conf.http_max_clients_arg) {
 294                 err_msg = "server full";
 295                 goto err_out;
 296         }
 297         match = host_in_acl(hc->fd, &http_acl);
 298         PARA_DEBUG_LOG("host_in_acl: %d\n", match);
 299         if ((match && !conf.http_default_deny_given) ||
 300                         (!match && conf.http_default_deny_given)) {
 301                 err_msg = "permission denied";
 302                 goto err_out;
 303         }
 304         hc->status = HTTP_CONNECTED;
 305         hc->cq = cq_new(MAX_BACKLOG);
 306         numclients++;
 307         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 308                 hc->name, hc->fd);
 309         para_list_add(&hc->node, &clients);
 310         add_close_on_fork_list(hc->fd);
 311         mark_fd_nonblocking(hc->fd);
 312         return;
 313 err_out:
 314         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 315                 hc->name, err_msg);
 316         if (hc->fd > 0)
 317                 close(hc->fd);
 318         free(hc);
 319 }
 320
 321 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 322 {
 323         struct http_client *hc, *tmp;
 324
 325         if (server_fd < 0)
 326                 return;
 327         para_fd_set(server_fd, rfds, max_fileno);
 328         list_for_each_entry_safe(hc, tmp, &clients, node) {
 329                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 330                 hc->check_r = 0;
 331                 hc->check_w = 0;
 332                 switch (hc->status) {
 333                 case HTTP_STREAMING:
 334                 case HTTP_READY_TO_STREAM:
 335                         break;
 336                 case HTTP_CONNECTED: /* need to recv get request */
 337                         para_fd_set(hc->fd, rfds, max_fileno);
 338                         hc->check_r = 1;
 339                         break;
 340                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 341                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 342                         para_fd_set(hc->fd, wfds, max_fileno);
 343                         hc->check_w = 1;
 344                         break;
 345                 case HTTP_SENT_OK_MSG:
 346                         if (!vss_playing())
 347                                 break; /* wait until server starts playing */
 348                         para_fd_set(hc->fd, wfds, max_fileno);
 349                         hc->check_w = 1;
 350                         break;
 351                 }
 352         }
 353 }
 354
 355 static int open_tcp_port(int port)
 356 {
 357         int ret;
 358
 359         server_fd = para_listen(AF_UNSPEC, IPPROTO_TCP, port);
 360         if (server_fd < 0) {
 361                 http_shutdown_clients();
 362                 self->status = SENDER_OFF;
 363                 return server_fd;
 364         }
 365         ret = mark_fd_nonblocking(server_fd);
 366         if (ret < 0) {
 367                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 368                 exit(EXIT_FAILURE);
 369         }
 370         self->status = SENDER_ON;
 371         add_close_on_fork_list(server_fd);
 372         return 1;
 373 }
 374
 375 static int http_com_on(__a_unused struct sender_command_data *scd)
 376 {
 377         if (self->status == SENDER_ON)
 378                 return 1;
 379         return open_tcp_port(conf.http_port_arg);
 380 }
 381
 382 static int http_com_off(__a_unused struct sender_command_data *scd)
 383 {
 384         self->status = SENDER_OFF;
 385         if (server_fd > 0) {
 386                 close(server_fd);
 387                 del_close_on_fork_list(server_fd);
 388                 server_fd = -1;
 389         }
 390         http_shutdown_clients();
 391         return 1;
 392 }
 393
 394 static void del_acl_entry(struct list_head *acl, struct in_addr addr,
 395                 int netmask)
 396 {
 397         struct access_info *ai, *tmp;
 398
 399         list_for_each_entry_safe(ai, tmp, acl, node) {
 400                 char *nad = para_strdup(inet_ntoa(ai->addr));
 401                 if (!strcmp(nad, inet_ntoa(addr)) &&
 402                                 ai->netmask == netmask) {
 403                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 404                                 nad, ai->netmask);
 405                         list_del(&ai->node);
 406                         free(ai);
 407                 }
 408                 free(nad);
 409         }
 410 }
 411
 412 static void add_acl_entry(struct list_head *acl, struct in_addr addr,
 413                 int netmask)
 414 {
 415         struct access_info *ai = para_malloc(sizeof(struct access_info));
 416         ai->addr = addr;
 417         ai->netmask = netmask;
 418         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 419                 ai->netmask);
 420         para_list_add(&ai->node, acl);
 421 }
 422
 423 static int http_com_deny(struct sender_command_data *scd)
 424 {
 425         if (conf.http_default_deny_given)
 426                 del_acl_entry(&http_acl, scd->addr, scd->netmask);
 427         else
 428                 add_acl_entry(&http_acl, scd->addr, scd->netmask);
 429         return 1;
 430 }
 431
 432 static int http_com_allow(struct sender_command_data *scd)
 433 {
 434         if (conf.http_default_deny_given)
 435                 add_acl_entry(&http_acl, scd->addr, scd->netmask);
 436         else
 437                 del_acl_entry(&http_acl, scd->addr, scd->netmask);
 438         return 1;
 439 }
 440
 441 static char *get_acl_contents(struct list_head *acl)
 442 {
 443         struct access_info *ai, *tmp_ai;
 444         char *ret = NULL;
 445
 446         list_for_each_entry_safe(ai, tmp_ai, acl, node) {
 447                 char *tmp = make_message("%s%s/%d ", ret? ret : "",
 448                         inet_ntoa(ai->addr), ai->netmask);
 449                 free(ret);
 450                 ret = tmp;
 451         }
 452         return ret;
 453 }
 454
 455 static char *http_info(void)
 456 {
 457         char *clnts = NULL, *ret;
 458         struct http_client *hc, *tmp_hc;
 459
 460         char *acl_contents = get_acl_contents(&http_acl);
 461         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 462                 char *tmp = make_message("%s%s ", clnts? clnts : "", hc->name);
 463                 free(clnts);
 464                 clnts = tmp;
 465         }
 466         ret = make_message(
 467                 "http status: %s\n"
 468                 "http tcp port: %d\n"
 469                 "http clients: %d\n"
 470                 "http maximal number of clients: %d%s\n"
 471                 "http connected clients: %s\n"
 472                 "http access %s list: %s\n",
 473                 (self->status == SENDER_ON)? "on" : "off",
 474                 conf.http_port_arg,
 475                 numclients,
 476                 conf.http_max_clients_arg,
 477                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 478                 clnts? clnts : "(none)",
 479                 conf.http_default_deny_given? "allow" : "deny",
 480                 acl_contents? acl_contents : "(none)"
 481         );
 482         free(acl_contents);
 483         free(clnts);
 484         return ret;
 485 }
 486
 487 static void init_acl(struct list_head *acl, char * const *acl_info, int num)
 488 {
 489         int i;
 490
 491         INIT_LIST_HEAD(acl);
 492         for (i = 0; i < num; i++) {
 493                 char *arg = para_strdup(acl_info[i]);
 494                 char *p = strchr(arg, '/');
 495                 struct in_addr addr;
 496                 int netmask;
 497
 498                 if (!p)
 499                         goto err;
 500                 *p = '\0';
 501                 if (!inet_pton(AF_INET, arg, &addr))
 502                         goto err;
 503                 netmask = atoi(++p);
 504                 if (netmask < 0 || netmask > 32)
 505                         goto err;
 506                 add_acl_entry(acl, addr, netmask);
 507                 goto success;
 508 err:
 509                 PARA_CRIT_LOG("syntax error: %s\n", acl_info[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_acl(&http_acl, conf.http_access_arg, conf.http_access_given);
 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 }