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 established, we might need to send the audio file header. */
  42         HTTP_READY_TO_STREAM,
  43         /** Connection is ready for sending audio data. */
  44         HTTP_STREAMING,
  45         /** We didn't receive a valid get request. */
  46         HTTP_INVALID_GET_REQUEST
  47 };
  48
  49 /** Clients will be kicked if there are more than that many bytes pending. */
  50 #define MAX_BACKLOG 400000
  51 /** The list of connected clients. */
  52 static struct list_head clients;
  53 /** The whitelist/blacklist. */
  54 static struct list_head http_acl;
  55
  56 /** Describes one client that connected the tcp port of the http sender. */
  57 struct http_client {
  58         /** The file descriptor of the client. */
  59         int fd;
  60         /** The socket `name' of the client. */
  61         char *name;
  62         /** The client's current status. */
  63         enum http_status status;
  64         /** Non-zero if we included \a fd in the read set.*/
  65         int check_r;
  66         /** Non-zero if we included \a fd in the write set. */
  67         int check_w;
  68         /** The position of this client in the client list. */
  69         struct list_head node;
  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                                 hc->status != HTTP_READY_TO_STREAM)
 176                         continue;
 177                 if (hc->status == HTTP_READY_TO_STREAM) {
 178                         size_t hlen;
 179                         char *hbuf = vss_get_header(&hlen);
 180                         if (hbuf && hlen > 0 && current_chunk) {
 181                                 /* need to send header */
 182                                 PARA_INFO_LOG("queueing header: %zu\n", hlen);
 183                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 184                                         continue;
 185                         } else
 186                                 PARA_INFO_LOG("no need to queue header\n");
 187                         hc->status = HTTP_STREAMING;
 188                 }
 189                 ret = send_queued_chunks(hc);
 190                 if (ret < 0) {
 191                         http_shutdown_client(hc, "queue send error");
 192                         continue;
 193                 }
 194                 if (!len)
 195                         continue;
 196                 if (!ret || write_ok(hc->fd) <= 0) {
 197                         queue_chunk_or_shutdown(hc, current_chunk, 0);
 198                         continue;
 199                 }
 200 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, remote_name(hc->fd));
 201                 ret = write(hc->fd, buf, len);
 202 //              PARA_DEBUG_LOG("ret: %d\n", ret);
 203                 if (ret < 0) {
 204                         http_shutdown_client(hc, "send error");
 205                         continue;
 206                 }
 207                 if (ret != len)
 208                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 209         }
 210 }
 211
 212 static void http_post_select(fd_set *rfds, fd_set *wfds)
 213 {
 214         int i = -1, match;
 215         struct http_client *hc, *tmp;
 216         const char *err_msg;
 217
 218         if (listen_fd < 0)
 219                 return;
 220         list_for_each_entry_safe(hc, tmp, &clients, node) {
 221                 i++;
 222 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, remote_name(hc->fd));
 223                 switch (hc->status) {
 224                 case HTTP_STREAMING: /* nothing to do */
 225                 case HTTP_READY_TO_STREAM:
 226                         break;
 227                 case HTTP_CONNECTED: /* need to recv get request */
 228                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 229                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 230                                                 < 0) {
 231                                         hc->status = HTTP_INVALID_GET_REQUEST;
 232                                 } else {
 233                                         hc->status = HTTP_GOT_GET_REQUEST;
 234                                         PARA_INFO_LOG("%s",
 235                                                 "received get request\n");
 236                                 }
 237                         }
 238                         break;
 239                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 240                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 241                                 hc->status = HTTP_SENT_OK_MSG;
 242                                 http_send_ok_msg(hc);
 243                         }
 244                         break;
 245                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 246                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 247                                 if (http_send_err_msg(hc) >= 0)
 248                                         http_shutdown_client(hc,
 249                                                 "invalid get request");
 250                         }
 251                         break;
 252                 case HTTP_SENT_OK_MSG: /* need to send header? */
 253                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 254                                 hc->status = HTTP_READY_TO_STREAM;
 255                         break;
 256                 }
 257         }
 258         if (!FD_ISSET(listen_fd, rfds))
 259                 return;
 260         hc = para_calloc(sizeof(struct http_client));
 261         err_msg = "accept error";
 262         hc->fd = para_accept(listen_fd, NULL, 0);
 263         if (hc->fd <= 0)
 264                 goto err_out;
 265         hc->name = make_message("%s", remote_name(hc->fd));
 266         PARA_NOTICE_LOG("connection from %s (fd %d)\n", hc->name, hc->fd);
 267         if (conf.http_max_clients_arg > 0 && numclients >=
 268                         conf.http_max_clients_arg) {
 269                 err_msg = "server full";
 270                 goto err_out;
 271         }
 272         match = acl_lookup(hc->fd, &http_acl);
 273         PARA_DEBUG_LOG("acl lookup returned %d\n", match);
 274         if ((match && !conf.http_default_deny_given) ||
 275                         (!match && conf.http_default_deny_given)) {
 276                 err_msg = "permission denied";
 277                 goto err_out;
 278         }
 279         err_msg = "failed to mark fd non-blocking";
 280         if (mark_fd_nonblocking(hc->fd) < 0)
 281                 goto err_out;
 282         hc->status = HTTP_CONNECTED;
 283         hc->cq = cq_new(MAX_BACKLOG);
 284         numclients++;
 285         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 286                 hc->name, hc->fd);
 287         para_list_add(&hc->node, &clients);
 288         add_close_on_fork_list(hc->fd);
 289         return;
 290 err_out:
 291         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 292                 hc->name, err_msg);
 293         if (hc->fd > 0)
 294                 close(hc->fd);
 295         free(hc);
 296 }
 297
 298 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 299 {
 300         struct http_client *hc, *tmp;
 301
 302         if (listen_fd < 0)
 303                 return;
 304         para_fd_set(listen_fd, rfds, max_fileno);
 305         list_for_each_entry_safe(hc, tmp, &clients, node) {
 306                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 307                 hc->check_r = 0;
 308                 hc->check_w = 0;
 309                 switch (hc->status) {
 310                 case HTTP_STREAMING:
 311                 case HTTP_READY_TO_STREAM:
 312                         break;
 313                 case HTTP_CONNECTED: /* need to recv get request */
 314                         para_fd_set(hc->fd, rfds, max_fileno);
 315                         hc->check_r = 1;
 316                         break;
 317                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 318                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 319                         para_fd_set(hc->fd, wfds, max_fileno);
 320                         hc->check_w = 1;
 321                         break;
 322                 case HTTP_SENT_OK_MSG:
 323                         if (!vss_playing())
 324                                 break; /* wait until server starts playing */
 325                         para_fd_set(hc->fd, wfds, max_fileno);
 326                         hc->check_w = 1;
 327                         break;
 328                 }
 329         }
 330 }
 331
 332 static int http_open(void)
 333 {
 334         int ret;
 335
 336         listen_fd = para_listen(AF_UNSPEC, IPPROTO_TCP, conf.http_port_arg);
 337         if (listen_fd < 0)
 338                 return listen_fd;
 339         ret = mark_fd_nonblocking(listen_fd);
 340         if (ret < 0) {
 341                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 342                 exit(EXIT_FAILURE);
 343         }
 344         add_close_on_fork_list(listen_fd);
 345         return 1;
 346 }
 347
 348 static int http_com_on(__a_unused struct sender_command_data *scd)
 349 {
 350         if (listen_fd >= 0)
 351                 return 1;
 352         return http_open();
 353 }
 354
 355 static int http_com_off(__a_unused struct sender_command_data *scd)
 356 {
 357         if (listen_fd < 0)
 358                 return 1;
 359         PARA_NOTICE_LOG("closing http port %d\n", conf.http_port_arg);
 360         close(listen_fd);
 361         del_close_on_fork_list(listen_fd);
 362         http_shutdown_clients();
 363         listen_fd = -1;
 364         return 1;
 365 }
 366
 367 static int http_com_deny(struct sender_command_data *scd)
 368 {
 369         if (conf.http_default_deny_given)
 370                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 371         else
 372                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 373         return 1;
 374 }
 375
 376 static int http_com_allow(struct sender_command_data *scd)
 377 {
 378         if (conf.http_default_deny_given)
 379                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 380         else
 381                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 382         return 1;
 383 }
 384
 385 static char *http_info(void)
 386 {
 387         char *clnts = NULL, *ret;
 388         struct http_client *hc, *tmp_hc;
 389
 390         char *acl_contents = acl_get_contents(&http_acl);
 391         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 392                 char *tmp = make_message("%s%s ", clnts? clnts : "", hc->name);
 393                 free(clnts);
 394                 clnts = tmp;
 395         }
 396         ret = make_message(
 397                 "http status: %s\n"
 398                 "http tcp port: %d\n"
 399                 "http clients: %d\n"
 400                 "http maximal number of clients: %d%s\n"
 401                 "http connected clients: %s\n"
 402                 "http access %s list: %s\n",
 403                 (listen_fd >= 0)? "on" : "off",
 404                 conf.http_port_arg,
 405                 numclients,
 406                 conf.http_max_clients_arg,
 407                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 408                 clnts? clnts : "(none)",
 409                 conf.http_default_deny_given? "allow" : "deny",
 410                 acl_contents? acl_contents : "(none)"
 411         );
 412         free(acl_contents);
 413         free(clnts);
 414         return ret;
 415 }
 416
 417 static char *http_help(void)
 418 {
 419         return make_message(
 420                 "usage: {on|off}\n"
 421                 "usage: {allow|deny} IP mask\n"
 422                 "example: allow 127.0.0.1 32\n"
 423         );
 424 }
 425
 426 /**
 427  * The init function of the http sender.
 428  *
 429  * \param s Pointer to the http sender struct.
 430  *
 431  * It initializes all function pointers of \a s, the client list and the access
 432  * control list. If the autostart option was given, the tcp port is opened.
 433  */
 434 void http_send_init(struct sender *s)
 435 {
 436         INIT_LIST_HEAD(&clients);
 437         s->info = http_info;
 438         s->send = http_send;
 439         s->pre_select = http_pre_select;
 440         s->post_select = http_post_select;
 441         s->shutdown_clients = http_shutdown_clients;
 442         s->help = http_help;
 443         s->client_cmds[SENDER_ON] = http_com_on;
 444         s->client_cmds[SENDER_OFF] = http_com_off;
 445         s->client_cmds[SENDER_DENY] = http_com_deny;
 446         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 447         s->client_cmds[SENDER_ADD] = NULL;
 448         s->client_cmds[SENDER_DELETE] = NULL;
 449         self = s;
 450         acl_init(&http_acl, conf.http_access_arg, conf.http_access_given);
 451         if (!conf.http_no_autostart_given)
 452                 http_open(); /* ignore errors */
 453         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 454 }