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
 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         return;
 128 }
 129
 130 static void http_shutdown_clients_real(void)
 131 {
 132         struct http_client *hc, *tmp;
 133         list_for_each_entry_safe(hc, tmp, &clients, node)
 134                 http_shutdown_client(hc, "afs request");
 135 }
 136 static void http_shutdown_clients(void)
 137 {
 138         struct http_client *hc, *tmp;
 139         list_for_each_entry_safe(hc, tmp, &clients, node)
 140                 if (hc->status == HTTP_STREAMING)
 141                         http_shutdown_client(hc, "afs request");
 142 }
 143
 144 static int http_send_msg(struct http_client *hc, const char *msg)
 145 {
 146         int ret = send_buffer(hc->fd, msg);
 147
 148         if (ret < 0)
 149                 http_shutdown_client(hc, "send msg failed");
 150         return ret;
 151 }
 152
 153 static void http_send_ok_msg(struct http_client *hc)
 154 {
 155         PARA_INFO_LOG("sending http ok message to fd %d\n", hc->fd);
 156         http_send_msg(hc, HTTP_OK_MSG);
 157 }
 158
 159 static int http_send_err_msg(struct http_client *hc)
 160 {
 161         PARA_NOTICE_LOG("sending bad request message to fd %d\n", hc->fd);
 162         return http_send_msg(hc, HTTP_ERR_MSG);
 163 }
 164
 165 static int queue_packet(struct http_client *hc, const char *buf, size_t len)
 166 {
 167         struct queued_packet *qp;
 168         if (hc->pq_bytes + len > MAX_BACKLOG) {
 169                 http_shutdown_client(hc, "packet queue overrun");
 170                 return -E_QUEUE;
 171         }
 172         qp = para_malloc(sizeof(struct queued_packet));
 173         hc->pq_bytes += len;
 174         qp->packet = para_malloc(len);
 175         memcpy(qp->packet, buf, len);
 176         qp->len = len;
 177         list_add_tail(&qp->node, &hc->packet_queue);
 178         PARA_INFO_LOG("%lu bytes queued for fd %d\n", hc->pq_bytes, hc->fd);
 179         return 1;
 180 }
 181
 182 static int send_queued_packets(struct http_client *hc)
 183 {
 184         int ret;
 185         struct queued_packet *qp, *tmp;
 186
 187         if (list_empty(&hc->packet_queue))
 188                 return 1;
 189         list_for_each_entry_safe(qp, tmp, &hc->packet_queue, node) {
 190                 ret = write_ok(hc->fd);
 191                 if (ret <= 0)
 192                         return ret? -E_WRITE_OK : 0;
 193                 ret = write(hc->fd, qp->packet, qp->len);
 194                 if (ret < 0)
 195                         return ret;
 196                 if (ret != qp->len) {
 197                         qp->len -= ret;
 198                         memmove(qp->packet, qp->packet + ret, qp->len);
 199                         return 0;
 200                 }
 201                 hc->pq_bytes -= qp->len;
 202                 free(qp->packet);
 203                 list_del(&qp->node);
 204                 free(qp);
 205         }
 206         return 1;
 207 }
 208
 209 static void http_send( long unsigned current_chunk,
 210         __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 211 {
 212         struct http_client *hc, *tmp;
 213         int ret;
 214
 215         list_for_each_entry_safe(hc, tmp, &clients, node) {
 216                 if (hc->status != HTTP_STREAMING &&
 217                                 hc->status != HTTP_READY_TO_STREAM)
 218                         continue;
 219                 if (hc->status == HTTP_READY_TO_STREAM) {
 220                         int hlen;
 221                         char *buf = afs_get_header(&hlen);
 222                         if (buf && hlen > 0 && current_chunk) {
 223                                 /* need to send header */
 224                                 PARA_INFO_LOG("queueing header: %d\n", hlen);
 225                                 if (queue_packet(hc, buf, hlen) < 0)
 226                                         continue;
 227                         } else
 228                                 PARA_INFO_LOG("%s", "no need to queue header\n");
 229                         hc->status = HTTP_STREAMING;
 230                 }
 231                 ret = send_queued_packets(hc);
 232                 if (ret < 0) {
 233                         http_shutdown_client(hc, "send error");
 234                         continue;
 235                 }
 236                 if (!len)
 237                         continue;
 238                 if (!ret || write_ok(hc->fd) <= 0) {
 239                         PARA_INFO_LOG("fd %d not ready (%lu bytes queued),"
 240                                 " trying to queue packet\n", hc->fd,
 241                                 hc->pq_bytes);
 242                         queue_packet(hc, buf, len);
 243                         continue;
 244                 }
 245 //              PARA_DEBUG_LOG("sending %d -> %s\n", len, CLIENT_ADDR(hc));
 246                 ret = write(hc->fd, buf, len);
 247                 if (ret < 0) {
 248                         http_shutdown_client(hc, "send error");
 249                         continue;
 250                 }
 251                 if (ret != len)
 252                         queue_packet(hc, buf + ret, len - ret);
 253         }
 254 }
 255
 256 static int host_in_access_perm_list(struct http_client *hc)
 257 {
 258         struct access_info *ai, *tmp;
 259         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 260                 unsigned mask = ((~0) >> ai->netmask);
 261                 if ((hc->addr.sin_addr.s_addr & mask) == (ai->addr.s_addr & mask))
 262                         return 1;
 263         }
 264         return 0;
 265 }
 266
 267 static void http_post_select(fd_set *rfds, fd_set *wfds)
 268 {
 269         int i = -1, match;
 270         struct http_client *hc, *tmp;
 271         const char *err_msg;
 272
 273         list_for_each_entry_safe(hc, tmp, &clients, node) {
 274                 i++;
 275 //              PARA_DEBUG_LOG("handling client %d: %s\n", i, CLIENT_ADDR(hc));
 276                 switch (hc->status) {
 277                 case HTTP_STREAMING: /* nothing to do */
 278                 case HTTP_READY_TO_STREAM:
 279                         break;
 280                 case HTTP_CONNECTED: /* need to recv get request */
 281                         if (hc->check_r && FD_ISSET(hc->fd, rfds)) {
 282                                 if (recv_pattern(hc->fd, HTTP_GET_MSG, MAXLINE)
 283                                                 < 0) {
 284                                         hc->status = HTTP_INVALID_GET_REQUEST;
 285                                 } else {
 286                                         hc->status = HTTP_GOT_GET_REQUEST;
 287                                         PARA_INFO_LOG("%s",
 288                                                 "received get request\n");
 289                                 }
 290                         }
 291                         break;
 292                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 293                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 294                                 hc->status = HTTP_SENT_OK_MSG;
 295                                 http_send_ok_msg(hc);
 296                         }
 297                         break;
 298                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 299                         if (hc->check_w && FD_ISSET(hc->fd, wfds)) {
 300                                 if (http_send_err_msg(hc) >= 0)
 301                                         http_shutdown_client(hc,
 302                                                 "invalid get request");
 303                         }
 304                         break;
 305                 case HTTP_SENT_OK_MSG: /* need to send header? */
 306                         if (hc->check_w && FD_ISSET(hc->fd, wfds))
 307                                 hc->status = HTTP_READY_TO_STREAM;
 308                         break;
 309                 }
 310         }
 311         if (!FD_ISSET(server_fd, rfds))
 312                 return;
 313         hc = para_calloc(sizeof(struct http_client));
 314         err_msg = "accept error";
 315         hc->fd = para_accept(server_fd, &hc->addr, sizeof(struct sockaddr_in));
 316         if (hc->fd <= 0)
 317                 goto err_out;
 318         PARA_NOTICE_LOG("connection from %s (fd %d)\n", CLIENT_ADDR(hc), hc->fd);
 319         if (conf.http_max_clients_arg > 0 && numclients >=
 320                         conf.http_max_clients_arg) {
 321                 err_msg = "server full";
 322                 goto err_out;
 323         }
 324         match = host_in_access_perm_list(hc);
 325         PARA_DEBUG_LOG("host_in_access_perm_list: %d\n", match);
 326         if ((match && !conf.http_default_deny_given) ||
 327                         (!match && conf.http_default_deny_given)) {
 328                 err_msg = "permission denied";
 329                 goto err_out;
 330         }
 331         hc->status = HTTP_CONNECTED;
 332         INIT_LIST_HEAD(&hc->packet_queue);
 333         PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
 334                 CLIENT_ADDR(hc), hc->fd);
 335         numclients++;
 336         list_add(&hc->node, &clients);
 337         return;
 338 err_out:
 339         PARA_WARNING_LOG("ignoring connect request from %s (%s)\n",
 340                 CLIENT_ADDR(hc), err_msg);
 341         if (hc->fd > 0)
 342                 close(hc->fd);
 343         free(hc);
 344 }
 345
 346 static void http_pre_select(int *max_fileno, fd_set *rfds, fd_set *wfds)
 347 {
 348         struct http_client *hc, *tmp;
 349
 350         if (server_fd < 0)
 351                 return;
 352         para_fd_set(server_fd, rfds, max_fileno);
 353         list_for_each_entry_safe(hc, tmp, &clients, node) {
 354                 //PARA_DEBUG_LOG("hc %p on fd %d: status %d\n", hc, hc->fd, hc->status);
 355                 hc->check_r = 0;
 356                 hc->check_w = 0;
 357                 switch (hc->status) {
 358                 case HTTP_STREAMING:
 359                 case HTTP_READY_TO_STREAM:
 360                         break;
 361                 case HTTP_CONNECTED: /* need to recv get request */
 362                         para_fd_set(hc->fd, rfds, max_fileno);
 363                         hc->check_r = 1;
 364                         break;
 365                 case HTTP_GOT_GET_REQUEST: /* need to send ok msg */
 366                 case HTTP_INVALID_GET_REQUEST: /* need to send err msg */
 367                         para_fd_set(hc->fd, wfds, max_fileno);
 368                         hc->check_w = 1;
 369                         break;
 370                 case HTTP_SENT_OK_MSG:
 371                         if (!afs_playing())
 372                                 break; /* wait until server starts playing */
 373                         para_fd_set(hc->fd, wfds, max_fileno);
 374                         hc->check_w = 1;
 375                         break;
 376                 }
 377         }
 378 }
 379
 380 static int open_tcp_port(int port)
 381 {
 382         server_fd = init_tcp_socket(port);
 383         if (server_fd < 0) {
 384                 http_shutdown_clients_real();
 385                 self->status = SENDER_OFF;
 386                 return server_fd;
 387         }
 388         self->status = SENDER_ON;
 389         add_close_on_fork_list(server_fd);
 390         return 1;
 391 }
 392
 393 static int http_com_on(__a_unused struct sender_command_data *scd)
 394 {
 395         if (self->status == SENDER_ON)
 396                 return 1;
 397         return open_tcp_port(conf.http_port_arg);
 398 }
 399
 400 static int http_com_off(__a_unused struct sender_command_data *scd)
 401 {
 402         self->status = SENDER_OFF;
 403         if (server_fd > 0) {
 404                 close(server_fd);
 405                 del_close_on_fork_list(server_fd);
 406                 server_fd = -1;
 407         }
 408         http_shutdown_clients_real();
 409         return 1;
 410 }
 411
 412 static void del_perm_list_entry(struct sender_command_data *scd)
 413 {
 414         struct access_info *ai, *tmp;
 415
 416         list_for_each_entry_safe(ai, tmp, &access_perm_list, node) {
 417                 char *nad = para_strdup(inet_ntoa(ai->addr));
 418                 if (!strcmp(nad, inet_ntoa(scd->addr)) &&
 419                                 ai->netmask == scd->netmask) {
 420                         PARA_NOTICE_LOG("removing %s/%i from access list\n",
 421                                 nad, ai->netmask);
 422                         list_del(&ai->node);
 423                         free(ai);
 424                 }
 425                 free(nad);
 426         }
 427 }
 428
 429 static void add_perm_list_entry(struct sender_command_data *scd)
 430 {
 431         struct access_info *ai = para_malloc(sizeof(struct access_info));
 432         ai->addr = scd->addr;
 433         ai->netmask = scd->netmask;
 434         PARA_INFO_LOG("adding %s/%i to access list\n", inet_ntoa(ai->addr),
 435                 ai->netmask);
 436         list_add(&ai->node, &access_perm_list);
 437 }
 438
 439 static int http_com_deny(struct sender_command_data *scd)
 440 {
 441         if (conf.http_default_deny_given)
 442                 del_perm_list_entry(scd);
 443         else
 444                 add_perm_list_entry(scd);
 445         return 1;
 446 }
 447
 448 static int http_com_allow(struct sender_command_data *scd)
 449 {
 450         if (conf.http_default_deny_given)
 451                 add_perm_list_entry(scd);
 452         else
 453                 del_perm_list_entry(scd);
 454         return 1;
 455 }
 456
 457 static char *http_info(void)
 458 {
 459         char *clnts = NULL, *ap = NULL, *ret;
 460         struct access_info *ai, *tmp_ai;
 461         struct http_client *hc, *tmp_hc;
 462
 463         list_for_each_entry_safe(ai, tmp_ai, &access_perm_list, node) {
 464                 char *tmp = make_message("%s%s/%d ", ap? ap : "",
 465                         inet_ntoa(ai->addr), ai->netmask);
 466                 free(ap);
 467                 ap = tmp;
 468         }
 469         list_for_each_entry_safe(hc, tmp_hc, &clients, node) {
 470                 char *tmp = make_message("%s%s:%d ", clnts? clnts : "",
 471                         CLIENT_ADDR(hc), CLIENT_PORT(hc));
 472                 free(clnts);
 473                 clnts = tmp;
 474         }
 475         ret = make_message(
 476                 "http status: %s\n"
 477                 "http tcp port: %d\n"
 478                 "http clients: %d\n"
 479                 "http maximal number of clients: %d%s\n"
 480                 "http connected clients: %s\n"
 481                 "http access %s list: %s\n",
 482                 (self->status == SENDER_ON)? "on" : "off",
 483                 conf.http_port_arg,
 484                 numclients,
 485                 conf.http_max_clients_arg,
 486                 conf.http_max_clients_arg > 0? "" : " (unlimited)",
 487                 clnts? clnts : "(none)",
 488                 conf.http_default_deny_given? "allow" : "deny",
 489                 ap? ap : "(none)"
 490         );
 491         free(ap);
 492         free(clnts);
 493         return ret;
 494 }
 495
 496 static void init_access_control_list(void)
 497 {
 498         int i;
 499         struct sender_command_data scd;
 500
 501         INIT_LIST_HEAD(&access_perm_list);
 502         for (i = 0; i < conf.http_access_given; i++) {
 503                 char *arg = para_strdup(conf.http_access_arg[i]);
 504                 char *p = strchr(arg, '/');
 505                 if (!p)
 506                         goto err;
 507                 *p = '\0';
 508                 if (!inet_aton(arg, &scd.addr))
 509                         goto err;
 510                 scd.netmask = atoi(++p);
 511                 if (scd.netmask < 0 || scd.netmask > 32)
 512                         goto err;
 513                 add_perm_list_entry(&scd);
 514                 goto success;
 515 err:
 516                 PARA_CRIT_LOG("syntax error for http_access option "
 517                         "#%d, ignoring\n", i);
 518 success:
 519                 free(arg);
 520                 continue;
 521         }
 522 }
 523
 524 static char *http_help(void)
 525 {
 526         return make_message(
 527                 "usage: {on|off}\n"
 528                 "usage: {allow|deny} IP mask\n"
 529                 "example: allow 127.0.0.1 32\n"
 530         );
 531 }
 532
 533 /**
 534  * the init function of the http sender
 535  *
 536  * \param s pointer to the http sender struct
 537  *
 538  * It initializes all function pointers of \a s, init the client list and the
 539  * acess control list as well. If autostart is wanted, open the tcp port.
 540  */
 541 void http_send_init(struct sender *s)
 542 {
 543         INIT_LIST_HEAD(&clients);
 544         s->info = http_info;
 545         s->send = http_send;
 546         s->pre_select = http_pre_select;
 547         s->post_select = http_post_select;
 548         s->shutdown_clients = http_shutdown_clients;
 549         s->help = http_help;
 550         s->client_cmds[SENDER_ON] = http_com_on;
 551         s->client_cmds[SENDER_OFF] = http_com_off;
 552         s->client_cmds[SENDER_DENY] = http_com_deny;
 553         s->client_cmds[SENDER_ALLOW] = http_com_allow;
 554         s->client_cmds[SENDER_ADD] = NULL;
 555         s->client_cmds[SENDER_DELETE] = NULL;
 556         self = s;
 557         init_access_control_list();
 558         if (!conf.http_no_autostart_given)
 559                 open_tcp_port(conf.http_port_arg); /* ignore errors */
 560         PARA_DEBUG_LOG("%s", "http sender init complete\n");
 561 }