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 #include "acl.h"
  28
  29 /** Message sent to clients that do not send a valid get request. */
  30 #define HTTP_ERR_MSG "HTTP/1.0 400 Bad Request\n"
  31
  32
  33 /** The possible states of a client from the server's POV. */
  34 enum http_status {
  35         /** We accepted the connection on the tcp socket. */
  36         HTTP_CONNECTED,
  37         /** Successfully received the get request. */
  38         HTTP_GOT_GET_REQUEST,
  39         /** We sent the OK message back to the client. */
  40         HTTP_SENT_OK_MSG,
  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 http_acl;
  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         /** non-zero if audio file header has been sent */
  69         int header_sent;
  70         /** The list of pending chunks for this client. */
  71         struct chunk_queue *cq;
  72 };
  73
  74 static int listen_fd = -1, numclients;
  75 static struct sender *self;
  76
  77
  78 static void http_shutdown_client(struct http_client *hc, const char *msg)
  79 {
  80         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", hc->name, hc->fd,
  81                 msg);
  82         numclients--;
  83         free(hc->name);
  84         close(hc->fd);
  85         del_close_on_fork_list(hc->fd);
  86         cq_destroy(hc->cq);
  87         list_del(&hc->node);
  88         free(hc);
  89 }
  90
  91 static void http_shutdown_clients(void)
  92 {
  93         struct http_client *hc, *tmp;
  94         list_for_each_entry_safe(hc, tmp, &clients, node)
  95                 http_shutdown_client(hc, "vss request");
  96 }
  97
  98 static int http_send_msg(struct http_client *hc, const char *msg)
  99 {
 100         int ret = send_buffer(hc->fd, msg);
 101
 102         if (ret < 0)
 103                 http_shutdown_client(hc, "send msg failed");
 104         return ret;
 105 }
 106
 107 static void http_send_ok_msg(struct http_client *hc)
 108 {
 109         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 110         http_send_msg(hc, HTTP_OK_MSG);
 111 }
 112
 113 static int http_send_err_msg(struct http_client *hc)
 114 {
 115         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 116         return http_send_msg(hc, HTTP_ERR_MSG);
 117 }
 118
 119 /*
 120  * ret: Negative on errors, zero if nothing was written and write returned
 121  * EAGAIN, number of bytes written else.
 122  */
 123 static int http_write(int fd, const char *buf, size_t len)
 124 {
 125         size_t written = 0;
 126
 127         while (written < len) {
 128                 int ret = write(fd, buf + written, len - written);
 129                 if (ret < 0 && errno == EAGAIN)
 130                         return written;
 131                 if (ret < 0)
 132                         return -ERRNO_TO_PARA_ERROR(errno);
 133                 written += ret;
 134         }
 135         return written;
 136 }
 137
 138
 139 static int send_queued_chunks(struct http_client *hc)
 140 {
 141         struct queued_chunk *qc;
 142         while ((qc = cq_peek(hc->cq))) {
 143                 char *buf;
 144                 size_t len;
 145                 int ret;
 146                 cq_get(qc, &buf, &len);
 147                 ret = http_write(hc->fd, buf, len);
 148                 if (ret < 0)
 149                         return ret;
 150                 cq_update(hc->cq, ret);
 151                 if (ret != len)
 152                         return 1;
 153                 cq_dequeue(hc->cq);
 154         }
 155         return 1;
 156 }
 157
 158 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 159         size_t sent)
 160 {
 161         int ret = cq_enqueue(hc->cq, chunk_num, sent);
 162         if (ret < 0)
 163                 http_shutdown_client(hc, "queue error");
 164         return ret;
 165 }
 166
 167 static void http_send(long unsigned current_chunk,
 168         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 169 {
 170         struct http_client *hc, *tmp;
 171         int ret;
 172
 173         list_for_each_entry_safe(hc, tmp, &clients, node) {
 174                 if (hc->status != HTTP_STREAMING)
 175                         continue;
 176                 if (!hc->header_sent && current_chunk) {
 177                         size_t hlen;
 178                         char *hbuf = vss_get_header(&hlen);
 179                         if (hbuf && hlen > 0) { /* need to send header */
 180                                 PARA_INFO_LOG("queueing header: %zu\n", hlen);
 181                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 182                                         continue;
 183                         } else
 184                                 PARA_INFO_LOG("no need to queue header\n");
 185                         hc->header_sent = 1;
 186                 }
 187                 ret = send_queued_chunks(hc);
 188                 if (ret < 0) {
 189                         http_shutdown_client(hc, "queue send error");
 190                         continue;
 191                 }
 192                 if (!len)
 193                         continue;
 194                 ret = http_write(hc->fd, buf, len);
 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 void http_post_select(fd_set *rfds, fd_set *wfds)
 205 {
 206         int i = -1, match;
 207         struct http_client *hc, *tmp;
 208         const char *err_msg;
 209
 210         if (listen_fd < 0)
 211                 return;
 212         list_for_each_entry_safe(hc, tmp, &clients, node) {
 213                 i++;
 214 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, remote_name(hc->fd));
 215                 switch (hc->status) {
 216                 case HTTP_STREAMING: /* nothing to do */
 217                         break;
 218                 case HTTP_CONNECTED: /* need to recv get request */
 219                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 220                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 221                                                 < 0) {
 222                                         hc->status = HTTP_INVALID_GET_REQUEST;
 223                                 } else {
 224                                         hc->status = HTTP_GOT_GET_REQUEST;
 225                                         PARA_INFO_LOG("%s",
 226                                                 "received get request\n");
 227                                 }
 228                         }
 229                         break;
 230                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 231                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 232                                 hc->status = HTTP_SENT_OK_MSG;
 233                                 http_send_ok_msg(hc);
 234                         }
 235                         break;
 236                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 237                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 238                                 if (http_send_err_msg(hc) >= 0)
 239                                         http_shutdown_client(hc,
 240                                                 "invalid get request");
 241                         }
 242                         break;
 243                 case HTTP_SENT_OK_MSG: /* need to send header? */
 244                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 245                                 hc->status = HTTP_STREAMING;
 246                         break;
 247                 }
 248         }
 249         if (!FD_ISSET(listen_fd, rfds))
 250                 return;
 251         hc = para_calloc(sizeof(struct http_client));
 252         err_msg = "accept error";
 253         hc->fd = para_accept(listen_fd, NULL, 0);
 254         if (hc->fd <= 0)
 255                 goto err_out;
 256         hc->name = make_message("%s", remote_name(hc->fd));
 257         PARA_NOTICE_LOG("connection from %s (fd %d)\n", hc->name, hc->fd);
 258         if (conf.http_max_clients_arg > 0 && numclients >=
 259                         conf.http_max_clients_arg) {
 260                 err_msg = "server full";
 261                 goto err_out;
 262         }
 263         match = acl_lookup(hc->fd, &http_acl);
 264         PARA_DEBUG_LOG("acl lookup returned %d\n", match);
 265         if ((match && !conf.http_default_deny_given) ||
 266                         (!match && conf.http_default_deny_given)) {
 267                 err_msg = "permission denied";
 268                 goto err_out;
 269         }
 270         err_msg = "failed to mark fd non-blocking";
 271         if (mark_fd_nonblocking(hc->fd) < 0)
 272                 goto err_out;
 273         hc->status = HTTP_CONNECTED;
 274         hc->cq = cq_new(MAX_BACKLOG);
 275         numclients++;
 276         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 277                 hc->name, hc->fd);
 278         para_list_add(&hc->node, &clients);
 279         add_close_on_fork_list(hc->fd);
 280         return;
 281 err_out:
 282         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 283                 hc->name, err_msg);
 284         if (hc->fd > 0)
 285                 close(hc->fd);
 286         free(hc);
 287 }
 288
 289 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 290 {
 291         struct http_client *hc, *tmp;
 292
 293         if (listen_fd < 0)
 294                 return;
 295         para_fd_set(listen_fd, rfds, max_fileno);
 296         list_for_each_entry_safe(hc, tmp, &clients, node) {
 297                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 298                 hc->check_r = 0;
 299                 hc->check_w = 0;
 300                 switch (hc->status) {
 301                 case HTTP_STREAMING:
 302                         break;
 303                 case HTTP_CONNECTED: /* need to recv get request */
 304                         para_fd_set(hc->fd, rfds, max_fileno);
 305                         hc->check_r = 1;
 306                         break;
 307                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 308                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 309                         para_fd_set(hc->fd, wfds, max_fileno);
 310                         hc->check_w = 1;
 311                         break;
 312                 case HTTP_SENT_OK_MSG:
 313                         if (!vss_playing())
 314                                 break; /* wait until server starts playing */
 315                         para_fd_set(hc->fd, wfds, max_fileno);
 316                         hc->check_w = 1;
 317                         break;
 318                 }
 319         }
 320 }
 321
 322 static int http_open(void)
 323 {
 324         int ret;
 325
 326         listen_fd = para_listen(AF_UNSPEC, IPPROTO_TCP, conf.http_port_arg);
 327         if (listen_fd < 0)
 328                 return listen_fd;
 329         ret = mark_fd_nonblocking(listen_fd);
 330         if (ret < 0) {
 331                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 332                 exit(EXIT_FAILURE);
 333         }
 334         add_close_on_fork_list(listen_fd);
 335         return 1;
 336 }
 337
 338 static int http_com_on(__a_unused struct sender_command_data *scd)
 339 {
 340         if (listen_fd >= 0)
 341                 return 1;
 342         return http_open();
 343 }
 344
 345 static int http_com_off(__a_unused struct sender_command_data *scd)
 346 {
 347         if (listen_fd < 0)
 348                 return 1;
 349         PARA_NOTICE_LOG("closing http port %d\n", conf.http_port_arg);
 350         close(listen_fd);
 351         del_close_on_fork_list(listen_fd);
 352         http_shutdown_clients();
 353         listen_fd = -1;
 354         return 1;
 355 }
 356
 357 static int http_com_deny(struct sender_command_data *scd)
 358 {
 359         if (conf.http_default_deny_given)
 360                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 361         else
 362                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 363         return 1;
 364 }
 365
 366 static int http_com_allow(struct sender_command_data *scd)
 367 {
 368         if (conf.http_default_deny_given)
 369                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 370         else
 371                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 372         return 1;
 373 }
 374
 375 static char *http_info(void)
 376 {
 377         char *clnts = NULL, *ret;
 378         struct http_client *hc, *tmp_hc;
 379
 380         char *acl_contents = acl_get_contents(&http_acl);
 381         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 382                 char *tmp = make_message("%s%s ", clnts? clnts : "", hc->name);
 383                 free(clnts);
 384                 clnts = tmp;
 385         }
 386         ret = make_message(
 387                 "http status: %s\n"
 388                 "http tcp port: %d\n"
 389                 "http clients: %d\n"
 390                 "http maximal number of clients: %d%s\n"
 391                 "http connected clients: %s\n"
 392                 "http access %s list: %s\n",
 393                 (listen_fd >= 0)? "on" : "off",
 394                 conf.http_port_arg,
 395                 numclients,
 396                 conf.http_max_clients_arg,
 397                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 398                 clnts? clnts : "(none)",
 399                 conf.http_default_deny_given? "allow" : "deny",
 400                 acl_contents? acl_contents : "(none)"
 401         );
 402         free(acl_contents);
 403         free(clnts);
 404         return ret;
 405 }
 406
 407 static char *http_help(void)
 408 {
 409         return make_message(
 410                 "usage: {on|off}\n"
 411                 "usage: {allow|deny} IP mask\n"
 412                 "example: allow 127.0.0.1 32\n"
 413         );
 414 }
 415
 416 /**
 417  * The init function of the http sender.
 418  *
 419  * \param s Pointer to the http sender struct.
 420  *
 421  * It initializes all function pointers of \a s, the client list and the access
 422  * control list. If the autostart option was given, the tcp port is opened.
 423  */
 424 void http_send_init(struct sender *s)
 425 {
 426         INIT_LIST_HEAD(&clients);
 427         s->info = http_info;
 428         s->send = http_send;
 429         s->pre_select = http_pre_select;
 430         s->post_select = http_post_select;
 431         s->shutdown_clients = http_shutdown_clients;
 432         s->help = http_help;
 433         s->client_cmds[SENDER_ON] = http_com_on;
 434         s->client_cmds[SENDER_OFF] = http_com_off;
 435         s->client_cmds[SENDER_DENY] = http_com_deny;
 436         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 437         s->client_cmds[SENDER_ADD] = NULL;
 438         s->client_cmds[SENDER_DELETE] = NULL;
 439         self = s;
 440         acl_init(&http_acl, conf.http_access_arg, conf.http_access_given);
 441         if (!conf.http_no_autostart_given)
 442                 http_open(); /* ignore errors */
 443         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 444 }