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 "list.h"
  22 #include "send.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         /** The position of this client in the client list. */
  61         struct list_head node;
  62         /** non-zero if audio file header has been sent */
  63         int header_sent;
  64         /** The list of pending chunks for this client. */
  65         struct chunk_queue *cq;
  66 };
  67
  68 static int listen_fd = -1, numclients;
  69
  70
  71 static void http_shutdown_client(struct http_client *hc, const char *msg)
  72 {
  73         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", hc->name, hc->fd,
  74                 msg);
  75         numclients--;
  76         free(hc->name);
  77         close(hc->fd);
  78         del_close_on_fork_list(hc->fd);
  79         cq_destroy(hc->cq);
  80         list_del(&hc->node);
  81         free(hc);
  82 }
  83
  84 static void http_shutdown_clients(void)
  85 {
  86         struct http_client *hc, *tmp;
  87         list_for_each_entry_safe(hc, tmp, &clients, node)
  88                 http_shutdown_client(hc, "vss request");
  89 }
  90
  91 static int http_send_msg(struct http_client *hc, const char *msg)
  92 {
  93         int ret = send_buffer(hc->fd, msg);
  94
  95         if (ret < 0)
  96                 http_shutdown_client(hc, "send msg failed");
  97         return ret;
  98 }
  99
 100 static void http_send_ok_msg(struct http_client *hc)
 101 {
 102         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 103         http_send_msg(hc, HTTP_OK_MSG);
 104 }
 105
 106 static int http_send_err_msg(struct http_client *hc)
 107 {
 108         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 109         return http_send_msg(hc, HTTP_ERR_MSG);
 110 }
 111
 112 /*
 113  * ret: Negative on errors, zero if nothing was written and write returned
 114  * EAGAIN, number of bytes written else.
 115  */
 116 static int http_write(int fd, const char *buf, size_t len)
 117 {
 118         size_t written = 0;
 119
 120         while (written < len) {
 121                 int ret = write(fd, buf + written, len - written);
 122                 if (ret < 0 && errno == EAGAIN)
 123                         return written;
 124                 if (ret < 0)
 125                         return -ERRNO_TO_PARA_ERROR(errno);
 126                 written += ret;
 127         }
 128         return written;
 129 }
 130
 131
 132 static int send_queued_chunks(struct http_client *hc)
 133 {
 134         struct queued_chunk *qc;
 135         while ((qc = cq_peek(hc->cq))) {
 136                 char *buf;
 137                 size_t len;
 138                 int ret;
 139                 cq_get(qc, &buf, &len);
 140                 ret = http_write(hc->fd, buf, len);
 141                 if (ret < 0)
 142                         return ret;
 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                         continue;
 169                 if (!hc->header_sent && current_chunk) {
 170                         size_t hlen;
 171                         char *hbuf = vss_get_header(&hlen);
 172                         if (hbuf && hlen > 0) { /* need to send header */
 173                                 PARA_INFO_LOG("queueing header: %zu\n", hlen);
 174                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 175                                         continue;
 176                         } else
 177                                 PARA_INFO_LOG("no need to queue header\n");
 178                         hc->header_sent = 1;
 179                 }
 180                 ret = send_queued_chunks(hc);
 181                 if (ret < 0) {
 182                         http_shutdown_client(hc, "queue send error");
 183                         continue;
 184                 }
 185                 if (!len)
 186                         continue;
 187                 ret = http_write(hc->fd, buf, len);
 188                 if (ret < 0) {
 189                         http_shutdown_client(hc, "send error");
 190                         continue;
 191                 }
 192                 if (ret != len)
 193                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 194         }
 195 }
 196
 197 static void http_post_select(fd_set *rfds, __a_unused fd_set *wfds)
 198 {
 199         int i = -1, match;
 200         struct http_client *hc, *tmp;
 201         const char *err_msg;
 202
 203         if (listen_fd < 0)
 204                 return;
 205         list_for_each_entry_safe(hc, tmp, &clients, node) {
 206                 i++;
 207 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, remote_name(hc->fd));
 208                 switch (hc->status) {
 209                 case HTTP_STREAMING: /* nothing to do */
 210                         break;
 211                 case HTTP_CONNECTED: /* need to recv get request */
 212                         if (FD_ISSET(hc->fd, rfds)) {
 213                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 214                                                 < 0) {
 215                                         hc->status = HTTP_INVALID_GET_REQUEST;
 216                                 } else {
 217                                         hc->status = HTTP_GOT_GET_REQUEST;
 218                                         PARA_INFO_LOG("%s",
 219                                                 "received get request\n");
 220                                 }
 221                         }
 222                         break;
 223                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 224                         hc->status = HTTP_STREAMING;
 225                         http_send_ok_msg(hc);
 226                         break;
 227                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 228                         if (http_send_err_msg(hc) >= 0)
 229                                 http_shutdown_client(hc, "invalid get request");
 230                         break;
 231                 }
 232         }
 233         if (!FD_ISSET(listen_fd, rfds))
 234                 return;
 235         hc = para_calloc(sizeof(struct http_client));
 236         err_msg = "accept error";
 237         hc->fd = para_accept(listen_fd, NULL, 0);
 238         if (hc->fd <= 0)
 239                 goto err_out;
 240         hc->name = make_message("%s", remote_name(hc->fd));
 241         PARA_NOTICE_LOG("connection from %s (fd %d)\n", hc->name, hc->fd);
 242         if (conf.http_max_clients_arg > 0 && numclients >=
 243                         conf.http_max_clients_arg) {
 244                 err_msg = "server full";
 245                 goto err_out;
 246         }
 247         match = acl_lookup(hc->fd, &http_acl);
 248         PARA_DEBUG_LOG("acl lookup returned %d\n", match);
 249         if ((match && !conf.http_default_deny_given) ||
 250                         (!match && conf.http_default_deny_given)) {
 251                 err_msg = "permission denied";
 252                 goto err_out;
 253         }
 254         err_msg = "failed to mark fd non-blocking";
 255         if (mark_fd_nonblocking(hc->fd) < 0)
 256                 goto err_out;
 257         hc->status = HTTP_CONNECTED;
 258         hc->cq = cq_new(MAX_BACKLOG);
 259         numclients++;
 260         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 261                 hc->name, hc->fd);
 262         para_list_add(&hc->node, &clients);
 263         add_close_on_fork_list(hc->fd);
 264         return;
 265 err_out:
 266         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 267                 hc->name, err_msg);
 268         if (hc->fd > 0)
 269                 close(hc->fd);
 270         free(hc);
 271 }
 272
 273 static void http_pre_select(int *max_fileno, fd_set *rfds, __a_unused fd_set *wfds)
 274 {
 275         struct http_client *hc, *tmp;
 276
 277         if (listen_fd < 0)
 278                 return;
 279         para_fd_set(listen_fd, rfds, max_fileno);
 280         list_for_each_entry_safe(hc, tmp, &clients, node) {
 281                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 282                 switch (hc->status) {
 283                 case HTTP_STREAMING:
 284                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 285                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 286                         break;
 287                 case HTTP_CONNECTED: /* need to recv get request */
 288                         para_fd_set(hc->fd, rfds, max_fileno);
 289                         break;
 290                 }
 291         }
 292 }
 293
 294 static int http_open(void)
 295 {
 296         int ret;
 297
 298         listen_fd = para_listen(AF_UNSPEC, IPPROTO_TCP, conf.http_port_arg);
 299         if (listen_fd < 0)
 300                 return listen_fd;
 301         ret = mark_fd_nonblocking(listen_fd);
 302         if (ret < 0) {
 303                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 304                 exit(EXIT_FAILURE);
 305         }
 306         add_close_on_fork_list(listen_fd);
 307         return 1;
 308 }
 309
 310 static int http_com_on(__a_unused struct sender_command_data *scd)
 311 {
 312         if (listen_fd >= 0)
 313                 return 1;
 314         return http_open();
 315 }
 316
 317 static int http_com_off(__a_unused struct sender_command_data *scd)
 318 {
 319         if (listen_fd < 0)
 320                 return 1;
 321         PARA_NOTICE_LOG("closing http port %d\n", conf.http_port_arg);
 322         close(listen_fd);
 323         del_close_on_fork_list(listen_fd);
 324         http_shutdown_clients();
 325         listen_fd = -1;
 326         return 1;
 327 }
 328
 329 static int http_com_deny(struct sender_command_data *scd)
 330 {
 331         if (conf.http_default_deny_given)
 332                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 333         else
 334                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 335         return 1;
 336 }
 337
 338 static int http_com_allow(struct sender_command_data *scd)
 339 {
 340         if (conf.http_default_deny_given)
 341                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 342         else
 343                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 344         return 1;
 345 }
 346
 347 static char *http_info(void)
 348 {
 349         char *clnts = NULL, *ret;
 350         struct http_client *hc, *tmp_hc;
 351
 352         char *acl_contents = acl_get_contents(&http_acl);
 353         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 354                 char *tmp = make_message("%s%s ", clnts? clnts : "", hc->name);
 355                 free(clnts);
 356                 clnts = tmp;
 357         }
 358         ret = make_message(
 359                 "http status: %s\n"
 360                 "http tcp port: %d\n"
 361                 "http clients: %d\n"
 362                 "http maximal number of clients: %d%s\n"
 363                 "http connected clients: %s\n"
 364                 "http access %s list: %s\n",
 365                 (listen_fd >= 0)? "on" : "off",
 366                 conf.http_port_arg,
 367                 numclients,
 368                 conf.http_max_clients_arg,
 369                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 370                 clnts? clnts : "(none)",
 371                 conf.http_default_deny_given? "allow" : "deny",
 372                 acl_contents? acl_contents : "(none)"
 373         );
 374         free(acl_contents);
 375         free(clnts);
 376         return ret;
 377 }
 378
 379 static char *http_help(void)
 380 {
 381         return make_message(
 382                 "usage: {on|off}\n"
 383                 "usage: {allow|deny} IP mask\n"
 384                 "example: allow 127.0.0.1 32\n"
 385         );
 386 }
 387
 388 /**
 389  * The init function of the http sender.
 390  *
 391  * \param s Pointer to the http sender struct.
 392  *
 393  * It initializes all function pointers of \a s, the client list and the access
 394  * control list. If the autostart option was given, the tcp port is opened.
 395  */
 396 void http_send_init(struct sender *s)
 397 {
 398         INIT_LIST_HEAD(&clients);
 399         s->info = http_info;
 400         s->send = http_send;
 401         s->pre_select = http_pre_select;
 402         s->post_select = http_post_select;
 403         s->shutdown_clients = http_shutdown_clients;
 404         s->help = http_help;
 405         s->client_cmds[SENDER_ON] = http_com_on;
 406         s->client_cmds[SENDER_OFF] = http_com_off;
 407         s->client_cmds[SENDER_DENY] = http_com_deny;
 408         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 409         s->client_cmds[SENDER_ADD] = NULL;
 410         s->client_cmds[SENDER_DELETE] = NULL;
 411         acl_init(&http_acl, conf.http_access_arg, conf.http_access_given);
 412         if (!conf.http_no_autostart_given)
 413                 http_open(); /* ignore errors */
 414         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 415 }