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         /** Connection is ready for sending audio data. */
  40         HTTP_STREAMING,
  41         /** We didn't receive a valid get request. */
  42         HTTP_INVALID_GET_REQUEST
  43 };
  44
  45 /** Clients will be kicked if there are more than that many bytes pending. */
  46 #define MAX_BACKLOG 400000
  47 /** The list of connected clients. */
  48 static struct list_head clients;
  49 /** The whitelist/blacklist. */
  50 static struct list_head http_acl;
  51
  52 /** Describes one client that connected the tcp port of the http sender. */
  53 struct http_client {
  54         /** The file descriptor of the client. */
  55         int fd;
  56         /** The socket `name' of the client. */
  57         char *name;
  58         /** The client's current status. */
  59         enum http_status status;
  60         /** Non-zero if we included \a fd in the read set.*/
  61         int check_r;
  62         /** The position of this client in the client list. */
  63         struct list_head node;
  64         /** non-zero if audio file header has been sent */
  65         int header_sent;
  66         /** The list of pending chunks for this client. */
  67         struct chunk_queue *cq;
  68 };
  69
  70 static int listen_fd = -1, numclients;
  71
  72
  73 static void http_shutdown_client(struct http_client *hc, const char *msg)
  74 {
  75         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", hc->name, hc->fd,
  76                 msg);
  77         numclients--;
  78         free(hc->name);
  79         close(hc->fd);
  80         del_close_on_fork_list(hc->fd);
  81         cq_destroy(hc->cq);
  82         list_del(&hc->node);
  83         free(hc);
  84 }
  85
  86 static void http_shutdown_clients(void)
  87 {
  88         struct http_client *hc, *tmp;
  89         list_for_each_entry_safe(hc, tmp, &clients, node)
  90                 http_shutdown_client(hc, "vss request");
  91 }
  92
  93 static int http_send_msg(struct http_client *hc, const char *msg)
  94 {
  95         int ret = send_buffer(hc->fd, msg);
  96
  97         if (ret < 0)
  98                 http_shutdown_client(hc, "send msg failed");
  99         return ret;
 100 }
 101
 102 static void http_send_ok_msg(struct http_client *hc)
 103 {
 104         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 105         http_send_msg(hc, HTTP_OK_MSG);
 106 }
 107
 108 static int http_send_err_msg(struct http_client *hc)
 109 {
 110         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 111         return http_send_msg(hc, HTTP_ERR_MSG);
 112 }
 113
 114 /*
 115  * ret: Negative on errors, zero if nothing was written and write returned
 116  * EAGAIN, number of bytes written else.
 117  */
 118 static int http_write(int fd, const char *buf, size_t len)
 119 {
 120         size_t written = 0;
 121
 122         while (written < len) {
 123                 int ret = write(fd, buf + written, len - written);
 124                 if (ret < 0 && errno == EAGAIN)
 125                         return written;
 126                 if (ret < 0)
 127                         return -ERRNO_TO_PARA_ERROR(errno);
 128                 written += ret;
 129         }
 130         return written;
 131 }
 132
 133
 134 static int send_queued_chunks(struct http_client *hc)
 135 {
 136         struct queued_chunk *qc;
 137         while ((qc = cq_peek(hc->cq))) {
 138                 char *buf;
 139                 size_t len;
 140                 int ret;
 141                 cq_get(qc, &buf, &len);
 142                 ret = http_write(hc->fd, buf, len);
 143                 if (ret < 0)
 144                         return ret;
 145                 cq_update(hc->cq, ret);
 146                 if (ret != len)
 147                         return 1;
 148                 cq_dequeue(hc->cq);
 149         }
 150         return 1;
 151 }
 152
 153 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 154         size_t sent)
 155 {
 156         int ret = cq_enqueue(hc->cq, chunk_num, sent);
 157         if (ret < 0)
 158                 http_shutdown_client(hc, "queue error");
 159         return ret;
 160 }
 161
 162 static void http_send(long unsigned current_chunk,
 163         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 164 {
 165         struct http_client *hc, *tmp;
 166         int ret;
 167
 168         list_for_each_entry_safe(hc, tmp, &clients, node) {
 169                 if (hc->status != HTTP_STREAMING)
 170                         continue;
 171                 if (!hc->header_sent && current_chunk) {
 172                         size_t hlen;
 173                         char *hbuf = vss_get_header(&hlen);
 174                         if (hbuf && hlen > 0) { /* 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->header_sent = 1;
 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                 ret = http_write(hc->fd, buf, len);
 190                 if (ret < 0) {
 191                         http_shutdown_client(hc, "send error");
 192                         continue;
 193                 }
 194                 if (ret != len)
 195                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 196         }
 197 }
 198
 199 static void http_post_select(fd_set *rfds, __a_unused fd_set *wfds)
 200 {
 201         int i = -1, match;
 202         struct http_client *hc, *tmp;
 203         const char *err_msg;
 204
 205         if (listen_fd < 0)
 206                 return;
 207         list_for_each_entry_safe(hc, tmp, &clients, node) {
 208                 i++;
 209 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, remote_name(hc->fd));
 210                 switch (hc->status) {
 211                 case HTTP_STREAMING: /* nothing to do */
 212                         break;
 213                 case HTTP_CONNECTED: /* need to recv get request */
 214                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 215                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 216                                                 < 0) {
 217                                         hc->status = HTTP_INVALID_GET_REQUEST;
 218                                 } else {
 219                                         hc->status = HTTP_GOT_GET_REQUEST;
 220                                         PARA_INFO_LOG("%s",
 221                                                 "received get request\n");
 222                                 }
 223                         }
 224                         break;
 225                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 226                         hc->status = HTTP_STREAMING;
 227                         http_send_ok_msg(hc);
 228                         break;
 229                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 230                         if (http_send_err_msg(hc) >= 0)
 231                                 http_shutdown_client(hc, "invalid get request");
 232                         break;
 233                 }
 234         }
 235         if (!FD_ISSET(listen_fd, rfds))
 236                 return;
 237         hc = para_calloc(sizeof(struct http_client));
 238         err_msg = "accept error";
 239         hc->fd = para_accept(listen_fd, NULL, 0);
 240         if (hc->fd <= 0)
 241                 goto err_out;
 242         hc->name = make_message("%s", remote_name(hc->fd));
 243         PARA_NOTICE_LOG("connection from %s (fd %d)\n", hc->name, hc->fd);
 244         if (conf.http_max_clients_arg > 0 && numclients >=
 245                         conf.http_max_clients_arg) {
 246                 err_msg = "server full";
 247                 goto err_out;
 248         }
 249         match = acl_lookup(hc->fd, &http_acl);
 250         PARA_DEBUG_LOG("acl lookup returned %d\n", match);
 251         if ((match && !conf.http_default_deny_given) ||
 252                         (!match && conf.http_default_deny_given)) {
 253                 err_msg = "permission denied";
 254                 goto err_out;
 255         }
 256         err_msg = "failed to mark fd non-blocking";
 257         if (mark_fd_nonblocking(hc->fd) < 0)
 258                 goto err_out;
 259         hc->status = HTTP_CONNECTED;
 260         hc->cq = cq_new(MAX_BACKLOG);
 261         numclients++;
 262         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 263                 hc->name, hc->fd);
 264         para_list_add(&hc->node, &clients);
 265         add_close_on_fork_list(hc->fd);
 266         return;
 267 err_out:
 268         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 269                 hc->name, err_msg);
 270         if (hc->fd > 0)
 271                 close(hc->fd);
 272         free(hc);
 273 }
 274
 275 static void http_pre_select(int *max_fileno, fd_set *rfds, __a_unused fd_set *wfds)
 276 {
 277         struct http_client *hc, *tmp;
 278
 279         if (listen_fd < 0)
 280                 return;
 281         para_fd_set(listen_fd, rfds, max_fileno);
 282         list_for_each_entry_safe(hc, tmp, &clients, node) {
 283                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 284                 hc->check_r = 0;
 285                 switch (hc->status) {
 286                 case HTTP_STREAMING:
 287                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 288                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 289                         break;
 290                 case HTTP_CONNECTED: /* need to recv get request */
 291                         para_fd_set(hc->fd, rfds, max_fileno);
 292                         hc->check_r = 1;
 293                         break;
 294                 }
 295         }
 296 }
 297
 298 static int http_open(void)
 299 {
 300         int ret;
 301
 302         listen_fd = para_listen(AF_UNSPEC, IPPROTO_TCP, conf.http_port_arg);
 303         if (listen_fd < 0)
 304                 return listen_fd;
 305         ret = mark_fd_nonblocking(listen_fd);
 306         if (ret < 0) {
 307                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 308                 exit(EXIT_FAILURE);
 309         }
 310         add_close_on_fork_list(listen_fd);
 311         return 1;
 312 }
 313
 314 static int http_com_on(__a_unused struct sender_command_data *scd)
 315 {
 316         if (listen_fd >= 0)
 317                 return 1;
 318         return http_open();
 319 }
 320
 321 static int http_com_off(__a_unused struct sender_command_data *scd)
 322 {
 323         if (listen_fd < 0)
 324                 return 1;
 325         PARA_NOTICE_LOG("closing http port %d\n", conf.http_port_arg);
 326         close(listen_fd);
 327         del_close_on_fork_list(listen_fd);
 328         http_shutdown_clients();
 329         listen_fd = -1;
 330         return 1;
 331 }
 332
 333 static int http_com_deny(struct sender_command_data *scd)
 334 {
 335         if (conf.http_default_deny_given)
 336                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 337         else
 338                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 339         return 1;
 340 }
 341
 342 static int http_com_allow(struct sender_command_data *scd)
 343 {
 344         if (conf.http_default_deny_given)
 345                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 346         else
 347                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 348         return 1;
 349 }
 350
 351 static char *http_info(void)
 352 {
 353         char *clnts = NULL, *ret;
 354         struct http_client *hc, *tmp_hc;
 355
 356         char *acl_contents = acl_get_contents(&http_acl);
 357         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 358                 char *tmp = make_message("%s%s ", clnts? clnts : "", hc->name);
 359                 free(clnts);
 360                 clnts = tmp;
 361         }
 362         ret = make_message(
 363                 "http status: %s\n"
 364                 "http tcp port: %d\n"
 365                 "http clients: %d\n"
 366                 "http maximal number of clients: %d%s\n"
 367                 "http connected clients: %s\n"
 368                 "http access %s list: %s\n",
 369                 (listen_fd >= 0)? "on" : "off",
 370                 conf.http_port_arg,
 371                 numclients,
 372                 conf.http_max_clients_arg,
 373                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 374                 clnts? clnts : "(none)",
 375                 conf.http_default_deny_given? "allow" : "deny",
 376                 acl_contents? acl_contents : "(none)"
 377         );
 378         free(acl_contents);
 379         free(clnts);
 380         return ret;
 381 }
 382
 383 static char *http_help(void)
 384 {
 385         return make_message(
 386                 "usage: {on|off}\n"
 387                 "usage: {allow|deny} IP mask\n"
 388                 "example: allow 127.0.0.1 32\n"
 389         );
 390 }
 391
 392 /**
 393  * The init function of the http sender.
 394  *
 395  * \param s Pointer to the http sender struct.
 396  *
 397  * It initializes all function pointers of \a s, the client list and the access
 398  * control list. If the autostart option was given, the tcp port is opened.
 399  */
 400 void http_send_init(struct sender *s)
 401 {
 402         INIT_LIST_HEAD(&clients);
 403         s->info = http_info;
 404         s->send = http_send;
 405         s->pre_select = http_pre_select;
 406         s->post_select = http_post_select;
 407         s->shutdown_clients = http_shutdown_clients;
 408         s->help = http_help;
 409         s->client_cmds[SENDER_ON] = http_com_on;
 410         s->client_cmds[SENDER_OFF] = http_com_off;
 411         s->client_cmds[SENDER_DENY] = http_com_deny;
 412         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 413         s->client_cmds[SENDER_ADD] = NULL;
 414         s->client_cmds[SENDER_DELETE] = NULL;
 415         acl_init(&http_acl, conf.http_access_arg, conf.http_access_given);
 416         if (!conf.http_no_autostart_given)
 417                 http_open(); /* ignore errors */
 418         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 419 }