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
  76
  77 static void http_shutdown_client(struct http_client *hc, const char *msg)
  78 {
  79         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", hc->name, hc->fd,
  80                 msg);
  81         numclients--;
  82         free(hc->name);
  83         close(hc->fd);
  84         del_close_on_fork_list(hc->fd);
  85         cq_destroy(hc->cq);
  86         list_del(&hc->node);
  87         free(hc);
  88 }
  89
  90 static void http_shutdown_clients(void)
  91 {
  92         struct http_client *hc, *tmp;
  93         list_for_each_entry_safe(hc, tmp, &clients, node)
  94                 http_shutdown_client(hc, "vss request");
  95 }
  96
  97 static int http_send_msg(struct http_client *hc, const char *msg)
  98 {
  99         int ret = send_buffer(hc->fd, msg);
 100
 101         if (ret < 0)
 102                 http_shutdown_client(hc, "send msg failed");
 103         return ret;
 104 }
 105
 106 static void http_send_ok_msg(struct http_client *hc)
 107 {
 108         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 109         http_send_msg(hc, HTTP_OK_MSG);
 110 }
 111
 112 static int http_send_err_msg(struct http_client *hc)
 113 {
 114         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 115         return http_send_msg(hc, HTTP_ERR_MSG);
 116 }
 117
 118 /*
 119  * ret: Negative on errors, zero if nothing was written and write returned
 120  * EAGAIN, number of bytes written else.
 121  */
 122 static int http_write(int fd, const char *buf, size_t len)
 123 {
 124         size_t written = 0;
 125
 126         while (written < len) {
 127                 int ret = write(fd, buf + written, len - written);
 128                 if (ret < 0 && errno == EAGAIN)
 129                         return written;
 130                 if (ret < 0)
 131                         return -ERRNO_TO_PARA_ERROR(errno);
 132                 written += ret;
 133         }
 134         return written;
 135 }
 136
 137
 138 static int send_queued_chunks(struct http_client *hc)
 139 {
 140         struct queued_chunk *qc;
 141         while ((qc = cq_peek(hc->cq))) {
 142                 char *buf;
 143                 size_t len;
 144                 int ret;
 145                 cq_get(qc, &buf, &len);
 146                 ret = http_write(hc->fd, buf, len);
 147                 if (ret < 0)
 148                         return ret;
 149                 cq_update(hc->cq, ret);
 150                 if (ret != len)
 151                         return 1;
 152                 cq_dequeue(hc->cq);
 153         }
 154         return 1;
 155 }
 156
 157 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 158         size_t sent)
 159 {
 160         int ret = cq_enqueue(hc->cq, chunk_num, sent);
 161         if (ret < 0)
 162                 http_shutdown_client(hc, "queue error");
 163         return ret;
 164 }
 165
 166 static void http_send(long unsigned current_chunk,
 167         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 168 {
 169         struct http_client *hc, *tmp;
 170         int ret;
 171
 172         list_for_each_entry_safe(hc, tmp, &clients, node) {
 173                 if (hc->status != HTTP_STREAMING)
 174                         continue;
 175                 if (!hc->header_sent && current_chunk) {
 176                         size_t hlen;
 177                         char *hbuf = vss_get_header(&hlen);
 178                         if (hbuf && hlen > 0) { /* need to send header */
 179                                 PARA_INFO_LOG("queueing header: %zu\n", hlen);
 180                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 181                                         continue;
 182                         } else
 183                                 PARA_INFO_LOG("no need to queue header\n");
 184                         hc->header_sent = 1;
 185                 }
 186                 ret = send_queued_chunks(hc);
 187                 if (ret < 0) {
 188                         http_shutdown_client(hc, "queue send error");
 189                         continue;
 190                 }
 191                 if (!len)
 192                         continue;
 193                 ret = http_write(hc->fd, buf, len);
 194                 if (ret < 0) {
 195                         http_shutdown_client(hc, "send error");
 196                         continue;
 197                 }
 198                 if (ret != len)
 199                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 200         }
 201 }
 202
 203 static void http_post_select(fd_set *rfds, fd_set *wfds)
 204 {
 205         int i = -1, match;
 206         struct http_client *hc, *tmp;
 207         const char *err_msg;
 208
 209         if (listen_fd < 0)
 210                 return;
 211         list_for_each_entry_safe(hc, tmp, &clients, node) {
 212                 i++;
 213 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, remote_name(hc->fd));
 214                 switch (hc->status) {
 215                 case HTTP_STREAMING: /* nothing to do */
 216                         break;
 217                 case HTTP_CONNECTED: /* need to recv get request */
 218                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 219                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 220                                                 < 0) {
 221                                         hc->status = HTTP_INVALID_GET_REQUEST;
 222                                 } else {
 223                                         hc->status = HTTP_GOT_GET_REQUEST;
 224                                         PARA_INFO_LOG("%s",
 225                                                 "received get request\n");
 226                                 }
 227                         }
 228                         break;
 229                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 230                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 231                                 hc->status = HTTP_SENT_OK_MSG;
 232                                 http_send_ok_msg(hc);
 233                         }
 234                         break;
 235                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 236                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 237                                 if (http_send_err_msg(hc) >= 0)
 238                                         http_shutdown_client(hc,
 239                                                 "invalid get request");
 240                         }
 241                         break;
 242                 case HTTP_SENT_OK_MSG: /* need to send header? */
 243                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 244                                 hc->status = HTTP_STREAMING;
 245                         break;
 246                 }
 247         }
 248         if (!FD_ISSET(listen_fd, rfds))
 249                 return;
 250         hc = para_calloc(sizeof(struct http_client));
 251         err_msg = "accept error";
 252         hc->fd = para_accept(listen_fd, NULL, 0);
 253         if (hc->fd <= 0)
 254                 goto err_out;
 255         hc->name = make_message("%s", remote_name(hc->fd));
 256         PARA_NOTICE_LOG("connection from %s (fd %d)\n", hc->name, hc->fd);
 257         if (conf.http_max_clients_arg > 0 && numclients >=
 258                         conf.http_max_clients_arg) {
 259                 err_msg = "server full";
 260                 goto err_out;
 261         }
 262         match = acl_lookup(hc->fd, &http_acl);
 263         PARA_DEBUG_LOG("acl lookup returned %d\n", match);
 264         if ((match && !conf.http_default_deny_given) ||
 265                         (!match && conf.http_default_deny_given)) {
 266                 err_msg = "permission denied";
 267                 goto err_out;
 268         }
 269         err_msg = "failed to mark fd non-blocking";
 270         if (mark_fd_nonblocking(hc->fd) < 0)
 271                 goto err_out;
 272         hc->status = HTTP_CONNECTED;
 273         hc->cq = cq_new(MAX_BACKLOG);
 274         numclients++;
 275         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 276                 hc->name, hc->fd);
 277         para_list_add(&hc->node, &clients);
 278         add_close_on_fork_list(hc->fd);
 279         return;
 280 err_out:
 281         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 282                 hc->name, err_msg);
 283         if (hc->fd > 0)
 284                 close(hc->fd);
 285         free(hc);
 286 }
 287
 288 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 289 {
 290         struct http_client *hc, *tmp;
 291
 292         if (listen_fd < 0)
 293                 return;
 294         para_fd_set(listen_fd, rfds, max_fileno);
 295         list_for_each_entry_safe(hc, tmp, &clients, node) {
 296                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 297                 hc->check_r = 0;
 298                 hc->check_w = 0;
 299                 switch (hc->status) {
 300                 case HTTP_STREAMING:
 301                         break;
 302                 case HTTP_CONNECTED: /* need to recv get request */
 303                         para_fd_set(hc->fd, rfds, max_fileno);
 304                         hc->check_r = 1;
 305                         break;
 306                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 307                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 308                         para_fd_set(hc->fd, wfds, max_fileno);
 309                         hc->check_w = 1;
 310                         break;
 311                 case HTTP_SENT_OK_MSG:
 312                         if (!vss_playing())
 313                                 break; /* wait until server starts playing */
 314                         para_fd_set(hc->fd, wfds, max_fileno);
 315                         hc->check_w = 1;
 316                         break;
 317                 }
 318         }
 319 }
 320
 321 static int http_open(void)
 322 {
 323         int ret;
 324
 325         listen_fd = para_listen(AF_UNSPEC, IPPROTO_TCP, conf.http_port_arg);
 326         if (listen_fd < 0)
 327                 return listen_fd;
 328         ret = mark_fd_nonblocking(listen_fd);
 329         if (ret < 0) {
 330                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 331                 exit(EXIT_FAILURE);
 332         }
 333         add_close_on_fork_list(listen_fd);
 334         return 1;
 335 }
 336
 337 static int http_com_on(__a_unused struct sender_command_data *scd)
 338 {
 339         if (listen_fd >= 0)
 340                 return 1;
 341         return http_open();
 342 }
 343
 344 static int http_com_off(__a_unused struct sender_command_data *scd)
 345 {
 346         if (listen_fd < 0)
 347                 return 1;
 348         PARA_NOTICE_LOG("closing http port %d\n", conf.http_port_arg);
 349         close(listen_fd);
 350         del_close_on_fork_list(listen_fd);
 351         http_shutdown_clients();
 352         listen_fd = -1;
 353         return 1;
 354 }
 355
 356 static int http_com_deny(struct sender_command_data *scd)
 357 {
 358         if (conf.http_default_deny_given)
 359                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 360         else
 361                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 362         return 1;
 363 }
 364
 365 static int http_com_allow(struct sender_command_data *scd)
 366 {
 367         if (conf.http_default_deny_given)
 368                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 369         else
 370                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 371         return 1;
 372 }
 373
 374 static char *http_info(void)
 375 {
 376         char *clnts = NULL, *ret;
 377         struct http_client *hc, *tmp_hc;
 378
 379         char *acl_contents = acl_get_contents(&http_acl);
 380         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 381                 char *tmp = make_message("%s%s ", clnts? clnts : "", hc->name);
 382                 free(clnts);
 383                 clnts = tmp;
 384         }
 385         ret = make_message(
 386                 "http status: %s\n"
 387                 "http tcp port: %d\n"
 388                 "http clients: %d\n"
 389                 "http maximal number of clients: %d%s\n"
 390                 "http connected clients: %s\n"
 391                 "http access %s list: %s\n",
 392                 (listen_fd >= 0)? "on" : "off",
 393                 conf.http_port_arg,
 394                 numclients,
 395                 conf.http_max_clients_arg,
 396                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 397                 clnts? clnts : "(none)",
 398                 conf.http_default_deny_given? "allow" : "deny",
 399                 acl_contents? acl_contents : "(none)"
 400         );
 401         free(acl_contents);
 402         free(clnts);
 403         return ret;
 404 }
 405
 406 static char *http_help(void)
 407 {
 408         return make_message(
 409                 "usage: {on|off}\n"
 410                 "usage: {allow|deny} IP mask\n"
 411                 "example: allow 127.0.0.1 32\n"
 412         );
 413 }
 414
 415 /**
 416  * The init function of the http sender.
 417  *
 418  * \param s Pointer to the http sender struct.
 419  *
 420  * It initializes all function pointers of \a s, the client list and the access
 421  * control list. If the autostart option was given, the tcp port is opened.
 422  */
 423 void http_send_init(struct sender *s)
 424 {
 425         INIT_LIST_HEAD(&clients);
 426         s->info = http_info;
 427         s->send = http_send;
 428         s->pre_select = http_pre_select;
 429         s->post_select = http_post_select;
 430         s->shutdown_clients = http_shutdown_clients;
 431         s->help = http_help;
 432         s->client_cmds[SENDER_ON] = http_com_on;
 433         s->client_cmds[SENDER_OFF] = http_com_off;
 434         s->client_cmds[SENDER_DENY] = http_com_deny;
 435         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 436         s->client_cmds[SENDER_ADD] = NULL;
 437         s->client_cmds[SENDER_DELETE] = NULL;
 438         acl_init(&http_acl, conf.http_access_arg, conf.http_access_given);
 439         if (!conf.http_no_autostart_given)
 440                 http_open(); /* ignore errors */
 441         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 442 }