http_send.c

   1 /*
   2  * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
   3  *
   4  *     This program is free software; you can redistribute it and/or modify
   5  *     it under the terms of the GNU General Public License as published by
   6  *     the Free Software Foundation; either version 2 of the License, or
   7  *     (at your option) any later version.
   8  *
   9  *     This program is distributed in the hope that it will be useful,
  10  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *     GNU General Public License for more details.
  13  *
  14  *     You should have received a copy of the GNU General Public License
  15  *     along with this program; if not, write to the Free Software
  16  *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  17  */
  18
  19 /** \file http_send.c paraslash's http sender */
  20
  21
  22 #include "server.cmdline.h"
  23 #include "server.h"
  24 #include "http.h"
  25 #include "afs.h"
  26 #include "send.h"
  27 #include "list.h"
  28 #include "close_on_fork.h"
  29 #include "error.h"
  30 #include "net.h"
  31 #include "string.h"
  32 #include "fd.h"
  33
  34 /** \cond convert sock_addr_in to ascii */
  35 #define CLIENT_ADDR(hc) inet_ntoa((hc)->addr.sin_addr)
  36 /* get the port number of a struct http_client */
  37 #define CLIENT_PORT(hc) (hc)->addr.sin_port
  38 #define HTTP_ERR_MSG "HTTP/1.0 400 Bad Request\n"
  39 /** \endcond */
  40
  41 extern struct gengetopt_args_info conf;
  42
  43 /** the possible states of a client from the server's POV */
  44 enum http_status {
  45         HTTP_CONNECTED,
  46         HTTP_GOT_GET_REQUEST,
  47         HTTP_SENT_OK_MSG,
  48         HTTP_READY_TO_STREAM,
  49         HTTP_STREAMING,
  50         HTTP_INVALID_GET_REQUEST
  51 };
  52
  53 /** clients will be kicked if there are more than that many bytes pending */
  54 #define MAX_BACKLOG 40000
  55 /** the list of connected clients **/
  56 static struct list_head clients;
  57 /** the whitelist/blacklist */
  58 static struct list_head access_perm_list;
  59
  60 /** describes one client that connected the tcp port of the http sender */
  61 struct http_client {
  62 /** the file descriptor of the client */
  63         int fd;
  64 /** address information about the client */
  65         struct sockaddr_in addr;
  66 /** the client's current status */
  67         enum http_status status;
  68 /** non-zero if we included \a fd in the read set */
  69         int check_r;
  70 /** non-zero if we included \a fd in the write set */
  71         int check_w;
  72 /** the position of this client in the client list */
  73         struct list_head node;
  74 /** the list of pending packets for this client */
  75         struct list_head packet_queue;
  76 /** the number of pending bytes for this client */
  77         unsigned long pq_bytes;
  78 };
  79
  80 /**
  81  * describes one queued data packet for a client
  82  *
  83  * The send function of the http sender checks each client fd for writing. If a
  84  * client fd is not ready, it tries to queue that packet for this client until
  85  * the number of queued bytes exceeds \p MAX_BACKLOG.
  86  */
  87 struct queued_packet {
  88 /** the length of the packet in bytes */
  89         unsigned int len;
  90 /** pointer to the packet data */
  91         char *packet;
  92 /** position of the packet in the packet list */
  93         struct list_head node;
  94 };
  95
  96 /**
  97  * describes one entry in the blacklist/whitelist of the http sender
  98  */
  99 struct access_info {
 100         /** the address to be black/whitelisted */
 101         struct in_addr addr;
 102         /** the netmask for this entry */
 103         int netmask;
 104         /** the position of this entry in the access_perm_list */
 105         struct list_head node;
 106 };
 107
 108 static int server_fd = -1, numclients;
 109 static struct sender *self;
 110
 111
 112 static void http_shutdown_client(struct http_client *hc, const char *msg)
 113 {
 114         struct queued_packet *qp, *tmp;
 115         PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", CLIENT_ADDR(hc),
 116                 hc->fd, msg);
 117         numclients--;
 118         close(hc->fd);
 119         del_close_on_fork_list(hc->fd);
 120         list_for_each_entry_safe(qp, tmp, &hc->packet_queue, node) {
 121                 free(qp->packet);
 122                 list_del(&qp->node);
 123                 free(qp);
 124         }
 125         list_del(&hc->node);
 126         free(hc);
 127 }
 128
 129 static void http_shutdown_clients(void)
 130 {
 131         struct http_client *hc, *tmp;
 132         list_for_each_entry_safe(hc, tmp, &clients, node)
 133                 http_shutdown_client(hc, "afs request");
 134 }
 135
 136 static int http_send_msg(struct http_client *hc, const char *msg)
 137 {
 138         int ret = send_buffer(hc->fd, msg);
 139
 140         if (ret < 0)
 141                 http_shutdown_client(hc, "send msg failed");
 142         return ret;
 143 }
 144
 145 static void http_send_ok_msg(struct http_client *hc)
 146 {
 147         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 148         http_send_msg(hc, HTTP_OK_MSG);
 149 }
 150
 151 static int http_send_err_msg(struct http_client *hc)
 152 {
 153         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 154         return http_send_msg(hc, HTTP_ERR_MSG);
 155 }
 156
 157 static int queue_packet(struct http_client *hc, const char *buf, size_t len)
 158 {
 159         struct queued_packet *qp;
 160         if (hc->pq_bytes + len > MAX_BACKLOG) {
 161                 http_shutdown_client(hc, "packet queue overrun");
 162                 return -E_QUEUE;
 163         }
 164         qp = para_malloc(sizeof(struct queued_packet));
 165         hc->pq_bytes += len;
 166         qp->packet = para_malloc(len);
 167         memcpy(qp->packet, buf, len);
 168         qp->len = len;
 169         list_add_tail(&qp->node, &hc->packet_queue);
 170         PARA_INFO_LOG("%lu bytes queued for fd %d\n", hc->pq_bytes, hc->fd);
 171         return 1;
 172 }
 173
 174 static int send_queued_packets(struct http_client *hc)
 175 {
 176         int ret;
 177         struct queued_packet *qp, *tmp;
 178
 179         if (list_empty(&hc->packet_queue))
 180                 return 1;
 181         list_for_each_entry_safe(qp, tmp, &hc->packet_queue, node) {
 182                 ret = write_ok(hc->fd);
 183                 if (ret <= 0)
 184                         return ret? -E_WRITE_OK : 0;
 185                 ret = write(hc->fd, qp->packet, qp->len);
 186                 if (ret < 0)
 187                         return ret;
 188                 if (ret != qp->len) {
 189                         qp->len -= ret;
 190                         memmove(qp->packet, qp->packet + ret, qp->len);
 191                         return 0;
 192                 }
 193                 hc->pq_bytes -= qp->len;
 194                 free(qp->packet);
 195                 list_del(&qp->node);
 196                 free(qp);
 197         }
 198         return 1;
 199 }
 200
 201 static void http_send( long unsigned current_chunk,
 202         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 203 {
 204         struct http_client *hc, *tmp;
 205         int ret;
 206
 207         list_for_each_entry_safe(hc, tmp, &clients, node) {
 208                 if (hc->status != HTTP_STREAMING &&
 209                                 hc->status != HTTP_READY_TO_STREAM)
 210                         continue;
 211                 if (hc->status == HTTP_READY_TO_STREAM) {
 212                         int hlen;
 213                         char *buf = afs_get_header(&hlen);
 214                         if (buf && hlen > 0 && current_chunk) {
 215                                 /* need to send header */
 216                                 PARA_INFO_LOG("queueing header: %d\n", hlen);
 217                                 if (queue_packet(hc, buf, hlen) < 0)
 218                                         continue;
 219                         } else
 220                                 PARA_INFO_LOG("%s", "no need to queue header\n");
 221                         hc->status = HTTP_STREAMING;
 222                 }
 223                 ret = send_queued_packets(hc);
 224                 if (ret < 0) {
 225                         http_shutdown_client(hc, "send error");
 226                         continue;
 227                 }
 228                 if (!len)
 229                         continue;
 230                 if (!ret || write_ok(hc->fd) <= 0) {
 231                         PARA_INFO_LOG("fd %d not ready (%lu bytes queued),"
 232                                 " trying to queue packet\n", hc->fd,
 233                                 hc->pq_bytes);
 234                         queue_packet(hc, buf, len);
 235                         continue;
 236                 }
 237 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, CLIENT_ADDR(hc));
 238                 ret = write(hc->fd, buf, len);
 239                 if (ret < 0) {
 240                         http_shutdown_client(hc, "send error");
 241                         continue;
 242                 }
 243                 if (ret != len)
 244                         queue_packet(hc, buf + ret, len - ret);
 245         }
 246 }
 247
 248 static int host_in_access_perm_list(struct http_client *hc)
 249 {
 250         struct access_info *ai, *tmp;
 251         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 252                 unsigned mask = ((~0) >> ai->netmask);
 253                 if ((hc->addr.sin_addr.s_addr & mask) == (ai->addr.s_addr & mask))
 254                         return 1;
 255         }
 256         return 0;
 257 }
 258
 259 static void http_post_select(fd_set *rfds, fd_set *wfds)
 260 {
 261         int i = -1, match;
 262         struct http_client *hc, *tmp;
 263         const char *err_msg;
 264
 265         list_for_each_entry_safe(hc, tmp, &clients, node) {
 266                 i++;
 267 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, CLIENT_ADDR(hc));
 268                 switch (hc->status) {
 269                 case HTTP_STREAMING: /* nothing to do */
 270                 case HTTP_READY_TO_STREAM:
 271                         break;
 272                 case HTTP_CONNECTED: /* need to recv get request */
 273                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 274                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 275                                                 < 0) {
 276                                         hc->status = HTTP_INVALID_GET_REQUEST;
 277                                 } else {
 278                                         hc->status = HTTP_GOT_GET_REQUEST;
 279                                         PARA_INFO_LOG("%s",
 280                                                 "received get request\n");
 281                                 }
 282                         }
 283                         break;
 284                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 285                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 286                                 hc->status = HTTP_SENT_OK_MSG;
 287                                 http_send_ok_msg(hc);
 288                         }
 289                         break;
 290                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 291                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 292                                 if (http_send_err_msg(hc) >= 0)
 293                                         http_shutdown_client(hc,
 294                                                 "invalid get request");
 295                         }
 296                         break;
 297                 case HTTP_SENT_OK_MSG: /* need to send header? */
 298                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 299                                 hc->status = HTTP_READY_TO_STREAM;
 300                         break;
 301                 }
 302         }
 303         if (!FD_ISSET(server_fd, rfds))
 304                 return;
 305         hc = para_calloc(sizeof(struct http_client));
 306         err_msg = "accept error";
 307         hc->fd = para_accept(server_fd, &hc->addr, sizeof(struct sockaddr_in));
 308         if (hc->fd <= 0)
 309                 goto err_out;
 310         PARA_NOTICE_LOG("connection from %s (fd %d)\n", CLIENT_ADDR(hc), hc->fd);
 311         if (conf.http_max_clients_arg > 0 && numclients >=
 312                         conf.http_max_clients_arg) {
 313                 err_msg = "server full";
 314                 goto err_out;
 315         }
 316         match = host_in_access_perm_list(hc);
 317         PARA_DEBUG_LOG("host_in_access_perm_list: %d\n", match);
 318         if ((match && !conf.http_default_deny_given) ||
 319                         (!match && conf.http_default_deny_given)) {
 320                 err_msg = "permission denied";
 321                 goto err_out;
 322         }
 323         hc->status = HTTP_CONNECTED;
 324         INIT_LIST_HEAD(&hc->packet_queue);
 325         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 326                 CLIENT_ADDR(hc), hc->fd);
 327         numclients++;
 328         list_add(&hc->node, &clients);
 329         add_close_on_fork_list(hc->fd);
 330         mark_fd_nonblock(hc->fd);
 331         return;
 332 err_out:
 333         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 334                 CLIENT_ADDR(hc), err_msg);
 335         if (hc->fd > 0)
 336                 close(hc->fd);
 337         free(hc);
 338 }
 339
 340 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 341 {
 342         struct http_client *hc, *tmp;
 343
 344         if (server_fd < 0)
 345                 return;
 346         para_fd_set(server_fd, rfds, max_fileno);
 347         list_for_each_entry_safe(hc, tmp, &clients, node) {
 348                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 349                 hc->check_r = 0;
 350                 hc->check_w = 0;
 351                 switch (hc->status) {
 352                 case HTTP_STREAMING:
 353                 case HTTP_READY_TO_STREAM:
 354                         break;
 355                 case HTTP_CONNECTED: /* need to recv get request */
 356                         para_fd_set(hc->fd, rfds, max_fileno);
 357                         hc->check_r = 1;
 358                         break;
 359                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 360                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 361                         para_fd_set(hc->fd, wfds, max_fileno);
 362                         hc->check_w = 1;
 363                         break;
 364                 case HTTP_SENT_OK_MSG:
 365                         if (!afs_playing())
 366                                 break; /* wait until server starts playing */
 367                         para_fd_set(hc->fd, wfds, max_fileno);
 368                         hc->check_w = 1;
 369                         break;
 370                 }
 371         }
 372 }
 373
 374 static int open_tcp_port(int port)
 375 {
 376         server_fd = init_tcp_socket(port);
 377         if (server_fd < 0) {
 378                 http_shutdown_clients();
 379                 self->status = SENDER_OFF;
 380                 return server_fd;
 381         }
 382         self->status = SENDER_ON;
 383         add_close_on_fork_list(server_fd);
 384         return 1;
 385 }
 386
 387 static int http_com_on(__a_unused struct sender_command_data *scd)
 388 {
 389         if (self->status == SENDER_ON)
 390                 return 1;
 391         return open_tcp_port(conf.http_port_arg);
 392 }
 393
 394 static int http_com_off(__a_unused struct sender_command_data *scd)
 395 {
 396         self->status = SENDER_OFF;
 397         if (server_fd > 0) {
 398                 close(server_fd);
 399                 del_close_on_fork_list(server_fd);
 400                 server_fd = -1;
 401         }
 402         http_shutdown_clients();
 403         return 1;
 404 }
 405
 406 static void del_perm_list_entry(struct sender_command_data *scd)
 407 {
 408         struct access_info *ai, *tmp;
 409
 410         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 411                 char *nad = para_strdup(inet_ntoa(ai->addr));
 412                 if (!strcmp(nad, inet_ntoa(scd->addr)) &&
 413                                 ai->netmask == scd->netmask) {
 414                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 415                                 nad, ai->netmask);
 416                         list_del(&ai->node);
 417                         free(ai);
 418                 }
 419                 free(nad);
 420         }
 421 }
 422
 423 static void add_perm_list_entry(struct sender_command_data *scd)
 424 {
 425         struct access_info *ai = para_malloc(sizeof(struct access_info));
 426         ai->addr = scd->addr;
 427         ai->netmask = scd->netmask;
 428         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 429                 ai->netmask);
 430         list_add(&ai->node, &access_perm_list);
 431 }
 432
 433 static int http_com_deny(struct sender_command_data *scd)
 434 {
 435         if (conf.http_default_deny_given)
 436                 del_perm_list_entry(scd);
 437         else
 438                 add_perm_list_entry(scd);
 439         return 1;
 440 }
 441
 442 static int http_com_allow(struct sender_command_data *scd)
 443 {
 444         if (conf.http_default_deny_given)
 445                 add_perm_list_entry(scd);
 446         else
 447                 del_perm_list_entry(scd);
 448         return 1;
 449 }
 450
 451 static char *http_info(void)
 452 {
 453         char *clnts = NULL, *ap = NULL, *ret;
 454         struct access_info *ai, *tmp_ai;
 455         struct http_client *hc, *tmp_hc;
 456
 457         list_for_each_entry_safe(ai, tmp_ai, &access_perm_list, node) {
 458                 char *tmp = make_message("%s%s/%d ", ap? ap : "",
 459                         inet_ntoa(ai->addr), ai->netmask);
 460                 free(ap);
 461                 ap = tmp;
 462         }
 463         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 464                 char *tmp = make_message("%s%s:%d ", clnts? clnts : "",
 465                         CLIENT_ADDR(hc), CLIENT_PORT(hc));
 466                 free(clnts);
 467                 clnts = tmp;
 468         }
 469         ret = make_message(
 470                 "http status: %s\n"
 471                 "http tcp port: %d\n"
 472                 "http clients: %d\n"
 473                 "http maximal number of clients: %d%s\n"
 474                 "http connected clients: %s\n"
 475                 "http access %s list: %s\n",
 476                 (self->status == SENDER_ON)? "on" : "off",
 477                 conf.http_port_arg,
 478                 numclients,
 479                 conf.http_max_clients_arg,
 480                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 481                 clnts? clnts : "(none)",
 482                 conf.http_default_deny_given? "allow" : "deny",
 483                 ap? ap : "(none)"
 484         );
 485         free(ap);
 486         free(clnts);
 487         return ret;
 488 }
 489
 490 static void init_access_control_list(void)
 491 {
 492         int i;
 493         struct sender_command_data scd;
 494
 495         INIT_LIST_HEAD(&access_perm_list);
 496         for (i = 0; i < conf.http_access_given; i++) {
 497                 char *arg = para_strdup(conf.http_access_arg[i]);
 498                 char *p = strchr(arg, '/');
 499                 if (!p)
 500                         goto err;
 501                 *p = '\0';
 502                 if (!inet_aton(arg, &scd.addr))
 503                         goto err;
 504                 scd.netmask = atoi(++p);
 505                 if (scd.netmask < 0 || scd.netmask > 32)
 506                         goto err;
 507                 add_perm_list_entry(&scd);
 508                 goto success;
 509 err:
 510                 PARA_CRIT_LOG("syntax error for http_access option "
 511                         "#%d, ignoring\n", i);
 512 success:
 513                 free(arg);
 514                 continue;
 515         }
 516 }
 517
 518 static char *http_help(void)
 519 {
 520         return make_message(
 521                 "usage: {on|off}\n"
 522                 "usage: {allow|deny} IP mask\n"
 523                 "example: allow 127.0.0.1 32\n"
 524         );
 525 }
 526
 527 /**
 528  * the init function of the http sender
 529  *
 530  * \param s pointer to the http sender struct
 531  *
 532  * It initializes all function pointers of \a s, init the client list and the
 533  * acess control list as well. If autostart is wanted, open the tcp port.
 534  */
 535 void http_send_init(struct sender *s)
 536 {
 537         INIT_LIST_HEAD(&clients);
 538         s->info = http_info;
 539         s->send = http_send;
 540         s->pre_select = http_pre_select;
 541         s->post_select = http_post_select;
 542         s->shutdown_clients = http_shutdown_clients;
 543         s->help = http_help;
 544         s->client_cmds[SENDER_ON] = http_com_on;
 545         s->client_cmds[SENDER_OFF] = http_com_off;
 546         s->client_cmds[SENDER_DENY] = http_com_deny;
 547         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 548         s->client_cmds[SENDER_ADD] = NULL;
 549         s->client_cmds[SENDER_DELETE] = NULL;
 550         self = s;
 551         init_access_control_list();
 552         if (!conf.http_no_autostart_given)
 553                 open_tcp_port(conf.http_port_arg); /* ignore errors */
 554         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 555 }