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         /** Non-zero if we included \a fd in the write set. */
  63         int check_w;
  64         /** The position of this client in the client list. */
  65         struct list_head node;
  66         /** non-zero if audio file header has been sent */
  67         int header_sent;
  68         /** The list of pending chunks for this client. */
  69         struct chunk_queue *cq;
  70 };
  71
  72 static int listen_fd = -1, numclients;
  73
  74
  75 static void http_shutdown_client(struct http_client *hc, const char *msg)
  76 {
  77         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", hc->name, hc->fd,
  78                 msg);
  79         numclients--;
  80         free(hc->name);
  81         close(hc->fd);
  82         del_close_on_fork_list(hc->fd);
  83         cq_destroy(hc->cq);
  84         list_del(&hc->node);
  85         free(hc);
  86 }
  87
  88 static void http_shutdown_clients(void)
  89 {
  90         struct http_client *hc, *tmp;
  91         list_for_each_entry_safe(hc, tmp, &clients, node)
  92                 http_shutdown_client(hc, "vss request");
  93 }
  94
  95 static int http_send_msg(struct http_client *hc, const char *msg)
  96 {
  97         int ret = send_buffer(hc->fd, msg);
  98
  99         if (ret < 0)
 100                 http_shutdown_client(hc, "send msg failed");
 101         return ret;
 102 }
 103
 104 static void http_send_ok_msg(struct http_client *hc)
 105 {
 106         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 107         http_send_msg(hc, HTTP_OK_MSG);
 108 }
 109
 110 static int http_send_err_msg(struct http_client *hc)
 111 {
 112         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 113         return http_send_msg(hc, HTTP_ERR_MSG);
 114 }
 115
 116 /*
 117  * ret: Negative on errors, zero if nothing was written and write returned
 118  * EAGAIN, number of bytes written else.
 119  */
 120 static int http_write(int fd, const char *buf, size_t len)
 121 {
 122         size_t written = 0;
 123
 124         while (written < len) {
 125                 int ret = write(fd, buf + written, len - written);
 126                 if (ret < 0 && errno == EAGAIN)
 127                         return written;
 128                 if (ret < 0)
 129                         return -ERRNO_TO_PARA_ERROR(errno);
 130                 written += ret;
 131         }
 132         return written;
 133 }
 134
 135
 136 static int send_queued_chunks(struct http_client *hc)
 137 {
 138         struct queued_chunk *qc;
 139         while ((qc = cq_peek(hc->cq))) {
 140                 char *buf;
 141                 size_t len;
 142                 int ret;
 143                 cq_get(qc, &buf, &len);
 144                 ret = http_write(hc->fd, buf, len);
 145                 if (ret < 0)
 146                         return ret;
 147                 cq_update(hc->cq, ret);
 148                 if (ret != len)
 149                         return 1;
 150                 cq_dequeue(hc->cq);
 151         }
 152         return 1;
 153 }
 154
 155 static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
 156         size_t sent)
 157 {
 158         int ret = cq_enqueue(hc->cq, chunk_num, sent);
 159         if (ret < 0)
 160                 http_shutdown_client(hc, "queue error");
 161         return ret;
 162 }
 163
 164 static void http_send(long unsigned current_chunk,
 165         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 166 {
 167         struct http_client *hc, *tmp;
 168         int ret;
 169
 170         list_for_each_entry_safe(hc, tmp, &clients, node) {
 171                 if (hc->status != HTTP_STREAMING)
 172                         continue;
 173                 if (!hc->header_sent && current_chunk) {
 174                         size_t hlen;
 175                         char *hbuf = vss_get_header(&hlen);
 176                         if (hbuf && hlen > 0) { /* need to send header */
 177                                 PARA_INFO_LOG("queueing header: %zu\n", hlen);
 178                                 if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
 179                                         continue;
 180                         } else
 181                                 PARA_INFO_LOG("no need to queue header\n");
 182                         hc->header_sent = 1;
 183                 }
 184                 ret = send_queued_chunks(hc);
 185                 if (ret < 0) {
 186                         http_shutdown_client(hc, "queue send error");
 187                         continue;
 188                 }
 189                 if (!len)
 190                         continue;
 191                 ret = http_write(hc->fd, buf, len);
 192                 if (ret < 0) {
 193                         http_shutdown_client(hc, "send error");
 194                         continue;
 195                 }
 196                 if (ret != len)
 197                         queue_chunk_or_shutdown(hc, current_chunk, ret);
 198         }
 199 }
 200
 201 static void http_post_select(fd_set *rfds, fd_set *wfds)
 202 {
 203         int i = -1, match;
 204         struct http_client *hc, *tmp;
 205         const char *err_msg;
 206
 207         if (listen_fd < 0)
 208                 return;
 209         list_for_each_entry_safe(hc, tmp, &clients, node) {
 210                 i++;
 211 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, remote_name(hc->fd));
 212                 switch (hc->status) {
 213                 case HTTP_STREAMING: /* nothing to do */
 214                         break;
 215                 case HTTP_CONNECTED: /* need to recv get request */
 216                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 217                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 218                                                 < 0) {
 219                                         hc->status = HTTP_INVALID_GET_REQUEST;
 220                                 } else {
 221                                         hc->status = HTTP_GOT_GET_REQUEST;
 222                                         PARA_INFO_LOG("%s",
 223                                                 "received get request\n");
 224                                 }
 225                         }
 226                         break;
 227                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 228                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 229                                 hc->status = HTTP_STREAMING;
 230                                 http_send_ok_msg(hc);
 231                         }
 232                         break;
 233                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 234                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 235                                 if (http_send_err_msg(hc) >= 0)
 236                                         http_shutdown_client(hc,
 237                                                 "invalid get request");
 238                         }
 239                         break;
 240                 }
 241         }
 242         if (!FD_ISSET(listen_fd, rfds))
 243                 return;
 244         hc = para_calloc(sizeof(struct http_client));
 245         err_msg = "accept error";
 246         hc->fd = para_accept(listen_fd, NULL, 0);
 247         if (hc->fd <= 0)
 248                 goto err_out;
 249         hc->name = make_message("%s", remote_name(hc->fd));
 250         PARA_NOTICE_LOG("connection from %s (fd %d)\n", hc->name, hc->fd);
 251         if (conf.http_max_clients_arg > 0 && numclients >=
 252                         conf.http_max_clients_arg) {
 253                 err_msg = "server full";
 254                 goto err_out;
 255         }
 256         match = acl_lookup(hc->fd, &http_acl);
 257         PARA_DEBUG_LOG("acl lookup returned %d\n", match);
 258         if ((match && !conf.http_default_deny_given) ||
 259                         (!match && conf.http_default_deny_given)) {
 260                 err_msg = "permission denied";
 261                 goto err_out;
 262         }
 263         err_msg = "failed to mark fd non-blocking";
 264         if (mark_fd_nonblocking(hc->fd) < 0)
 265                 goto err_out;
 266         hc->status = HTTP_CONNECTED;
 267         hc->cq = cq_new(MAX_BACKLOG);
 268         numclients++;
 269         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 270                 hc->name, hc->fd);
 271         para_list_add(&hc->node, &clients);
 272         add_close_on_fork_list(hc->fd);
 273         return;
 274 err_out:
 275         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 276                 hc->name, err_msg);
 277         if (hc->fd > 0)
 278                 close(hc->fd);
 279         free(hc);
 280 }
 281
 282 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 283 {
 284         struct http_client *hc, *tmp;
 285
 286         if (listen_fd < 0)
 287                 return;
 288         para_fd_set(listen_fd, rfds, max_fileno);
 289         list_for_each_entry_safe(hc, tmp, &clients, node) {
 290                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 291                 hc->check_r = 0;
 292                 hc->check_w = 0;
 293                 switch (hc->status) {
 294                 case HTTP_STREAMING:
 295                         break;
 296                 case HTTP_CONNECTED: /* need to recv get request */
 297                         para_fd_set(hc->fd, rfds, max_fileno);
 298                         hc->check_r = 1;
 299                         break;
 300                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 301                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 302                         para_fd_set(hc->fd, wfds, max_fileno);
 303                         hc->check_w = 1;
 304                         break;
 305                 }
 306         }
 307 }
 308
 309 static int http_open(void)
 310 {
 311         int ret;
 312
 313         listen_fd = para_listen(AF_UNSPEC, IPPROTO_TCP, conf.http_port_arg);
 314         if (listen_fd < 0)
 315                 return listen_fd;
 316         ret = mark_fd_nonblocking(listen_fd);
 317         if (ret < 0) {
 318                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 319                 exit(EXIT_FAILURE);
 320         }
 321         add_close_on_fork_list(listen_fd);
 322         return 1;
 323 }
 324
 325 static int http_com_on(__a_unused struct sender_command_data *scd)
 326 {
 327         if (listen_fd >= 0)
 328                 return 1;
 329         return http_open();
 330 }
 331
 332 static int http_com_off(__a_unused struct sender_command_data *scd)
 333 {
 334         if (listen_fd < 0)
 335                 return 1;
 336         PARA_NOTICE_LOG("closing http port %d\n", conf.http_port_arg);
 337         close(listen_fd);
 338         del_close_on_fork_list(listen_fd);
 339         http_shutdown_clients();
 340         listen_fd = -1;
 341         return 1;
 342 }
 343
 344 static int http_com_deny(struct sender_command_data *scd)
 345 {
 346         if (conf.http_default_deny_given)
 347                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 348         else
 349                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 350         return 1;
 351 }
 352
 353 static int http_com_allow(struct sender_command_data *scd)
 354 {
 355         if (conf.http_default_deny_given)
 356                 acl_add_entry(&http_acl, scd->addr, scd->netmask);
 357         else
 358                 acl_del_entry(&http_acl, scd->addr, scd->netmask);
 359         return 1;
 360 }
 361
 362 static char *http_info(void)
 363 {
 364         char *clnts = NULL, *ret;
 365         struct http_client *hc, *tmp_hc;
 366
 367         char *acl_contents = acl_get_contents(&http_acl);
 368         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 369                 char *tmp = make_message("%s%s ", clnts? clnts : "", hc->name);
 370                 free(clnts);
 371                 clnts = tmp;
 372         }
 373         ret = make_message(
 374                 "http status: %s\n"
 375                 "http tcp port: %d\n"
 376                 "http clients: %d\n"
 377                 "http maximal number of clients: %d%s\n"
 378                 "http connected clients: %s\n"
 379                 "http access %s list: %s\n",
 380                 (listen_fd >= 0)? "on" : "off",
 381                 conf.http_port_arg,
 382                 numclients,
 383                 conf.http_max_clients_arg,
 384                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 385                 clnts? clnts : "(none)",
 386                 conf.http_default_deny_given? "allow" : "deny",
 387                 acl_contents? acl_contents : "(none)"
 388         );
 389         free(acl_contents);
 390         free(clnts);
 391         return ret;
 392 }
 393
 394 static char *http_help(void)
 395 {
 396         return make_message(
 397                 "usage: {on|off}\n"
 398                 "usage: {allow|deny} IP mask\n"
 399                 "example: allow 127.0.0.1 32\n"
 400         );
 401 }
 402
 403 /**
 404  * The init function of the http sender.
 405  *
 406  * \param s Pointer to the http sender struct.
 407  *
 408  * It initializes all function pointers of \a s, the client list and the access
 409  * control list. If the autostart option was given, the tcp port is opened.
 410  */
 411 void http_send_init(struct sender *s)
 412 {
 413         INIT_LIST_HEAD(&clients);
 414         s->info = http_info;
 415         s->send = http_send;
 416         s->pre_select = http_pre_select;
 417         s->post_select = http_post_select;
 418         s->shutdown_clients = http_shutdown_clients;
 419         s->help = http_help;
 420         s->client_cmds[SENDER_ON] = http_com_on;
 421         s->client_cmds[SENDER_OFF] = http_com_off;
 422         s->client_cmds[SENDER_DENY] = http_com_deny;
 423         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 424         s->client_cmds[SENDER_ADD] = NULL;
 425         s->client_cmds[SENDER_DELETE] = NULL;
 426         acl_init(&http_acl, conf.http_access_arg, conf.http_access_given);
 427         if (!conf.http_no_autostart_given)
 428                 http_open(); /* ignore errors */
 429         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 430 }