src/main/tls_listen.c

   1 /*
   2  * tls.c
   3  *
   4  * Version:     $Id$
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  *
  20  * Copyright 2001  hereUare Communications, Inc. <raghud@hereuare.com>
  21  * Copyright 2003  Alan DeKok <aland@freeradius.org>
  22  * Copyright 2006  The FreeRADIUS server project
  23  */
  24
  25 #include <freeradius-devel/ident.h>
  26 RCSID("$Id$")
  27
  28 #include <freeradius-devel/radiusd.h>
  29 #include <freeradius-devel/process.h>
  30 #include <freeradius-devel/rad_assert.h>
  31
  32 #ifdef HAVE_SYS_STAT_H
  33 #include <sys/stat.h>
  34 #endif
  35
  36 #ifdef WITH_TLS
  37 #ifdef HAVE_OPENSSL_RAND_H
  38 #include <openssl/rand.h>
  39 #endif
  40
  41 #ifdef HAVE_OPENSSL_OCSP_H
  42 #include <openssl/ocsp.h>
  43 #endif
  44
  45 #ifdef HAVE_PTHREAD_H
  46 #define PTHREAD_MUTEX_LOCK pthread_mutex_lock
  47 #define PTHREAD_MUTEX_UNLOCK pthread_mutex_unlock
  48 #else
  49 #define PTHREAD_MUTEX_LOCK(_x)
  50 #define PTHREAD_MUTEX_UNLOCK(_x)
  51 #endif
  52
  53 static void dump_hex(const char *msg, const uint8_t *data, size_t data_len)
  54 {
  55         size_t i;
  56
  57         if (debug_flag < 3) return;
  58
  59         printf("%s %d\n", msg, (int) data_len);
  60         if (data_len > 256) data_len = 256;
  61
  62         for (i = 0; i < data_len; i++) {
  63                 if ((i & 0x0f) == 0x00) printf ("%02x: ", (unsigned int) i);
  64                 printf("%02x ", data[i]);
  65                 if ((i & 0x0f) == 0x0f) printf ("\n");
  66         }
  67         printf("\n");
  68         fflush(stdout);
  69 }
  70
  71 static void tls_socket_close(rad_listen_t *listener)
  72 {
  73         listen_socket_t *sock = listener->data;
  74
  75         listener->status = RAD_LISTEN_STATUS_REMOVE_FD;
  76         listener->tls = NULL; /* parent owns this! */
  77
  78         if (sock->parent) {
  79                 /*
  80                  *      Decrement the number of connections.
  81                  */
  82                 if (sock->parent->limit.num_connections > 0) {
  83                         sock->parent->limit.num_connections--;
  84                 }
  85                 if (sock->client->limit.num_connections > 0) {
  86                         sock->client->limit.num_connections--;
  87                 }
  88         }
  89
  90         /*
  91          *      Tell the event handler that an FD has disappeared.
  92          */
  93         DEBUG("Client has closed connection");
  94         event_new_fd(listener);
  95
  96         /*
  97          *      Do NOT free the listener here.  It's in use by
  98          *      a request, and will need to hang around until
  99          *      all of the requests are done.
 100          *
 101          *      It is instead free'd in remove_from_request_hash()
 102          */
 103 }
 104
 105 static int tls_socket_write(rad_listen_t *listener, REQUEST *request)
 106 {
 107         uint8_t *p;
 108         ssize_t rcode;
 109         listen_socket_t *sock = listener->data;
 110
 111         p = sock->ssn->dirty_out.data;
 112
 113         while (p < (sock->ssn->dirty_out.data + sock->ssn->dirty_out.used)) {
 114                 RDEBUG3("Writing to socket %d", request->packet->sockfd);
 115                 rcode = write(request->packet->sockfd, p,
 116                               (sock->ssn->dirty_out.data + sock->ssn->dirty_out.used) - p);
 117                 if (rcode <= 0) {
 118                         RDEBUG("Error writing to TLS socket: %s", strerror(errno));
 119
 120                         tls_socket_close(listener);
 121                         return 0;
 122                 }
 123                 p += rcode;
 124         }
 125
 126         sock->ssn->dirty_out.used = 0;
 127
 128         return 1;
 129 }
 130
 131
 132 static int tls_socket_recv(rad_listen_t *listener)
 133 {
 134         int doing_init = FALSE;
 135         ssize_t rcode;
 136         RADIUS_PACKET *packet;
 137         REQUEST *request;
 138         listen_socket_t *sock = listener->data;
 139         fr_tls_status_t status;
 140         RADCLIENT *client = sock->client;
 141
 142         if (!sock->packet) {
 143                 sock->packet = rad_alloc(NULL, 0);
 144                 if (!sock->packet) return 0;
 145
 146                 sock->packet->sockfd = listener->fd;
 147                 sock->packet->src_ipaddr = sock->other_ipaddr;
 148                 sock->packet->src_port = sock->other_port;
 149                 sock->packet->dst_ipaddr = sock->my_ipaddr;
 150                 sock->packet->dst_port = sock->my_port;
 151
 152                 if (sock->request) {
 153                         talloc_steal(sock->request, sock->packet);
 154                         sock->request->packet = sock->packet;
 155                 }
 156         }
 157
 158         /*
 159          *      Allocate a REQUEST for debugging.
 160          */
 161         if (!sock->request) {
 162                 sock->request = request = request_alloc();
 163                 if (!sock->request) {
 164                         radlog(L_ERR, "Out of memory");
 165                         return 0;
 166                 }
 167
 168                 rad_assert(request->packet == NULL);
 169                 rad_assert(sock->packet != NULL);
 170                 request->packet = sock->packet;
 171
 172                 request->component = "<core>";
 173                 request->component = "<tls-connect>";
 174
 175                 /*
 176                  *      Not sure if we should do this on every packet...
 177                  */
 178                 request->reply = rad_alloc(request, 0);
 179                 if (!request->reply) return 0;
 180
 181                 request->options = RAD_REQUEST_OPTION_DEBUG2;
 182
 183                 rad_assert(sock->ssn == NULL);
 184
 185                 sock->ssn = tls_new_session(listener->tls, sock->request,
 186                                             listener->tls->require_client_cert);
 187                 if (!sock->ssn) {
 188                         request_free(&sock->request);
 189                         sock->packet = NULL;
 190                         return 0;
 191                 }
 192
 193                 SSL_set_ex_data(sock->ssn->ssl, FR_TLS_EX_INDEX_REQUEST, (void *)request);
 194                 SSL_set_ex_data(sock->ssn->ssl, FR_TLS_EX_INDEX_CERTS, (void *)&request->packet->vps);
 195
 196                 doing_init = TRUE;
 197         }
 198
 199         rad_assert(sock->request != NULL);
 200         rad_assert(sock->request->packet != NULL);
 201         rad_assert(sock->packet != NULL);
 202         rad_assert(sock->ssn != NULL);
 203
 204         request = sock->request;
 205
 206         RDEBUG3("Reading from socket %d", request->packet->sockfd);
 207         PTHREAD_MUTEX_LOCK(&sock->mutex);
 208         rcode = read(request->packet->sockfd,
 209                      sock->ssn->dirty_in.data,
 210                      sizeof(sock->ssn->dirty_in.data));
 211         if ((rcode < 0) && (errno == ECONNRESET)) {
 212         do_close:
 213                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 214                 tls_socket_close(listener);
 215                 return 0;
 216         }
 217
 218         if (rcode < 0) {
 219                 RDEBUG("Error reading TLS socket: %s", strerror(errno));
 220                 goto do_close;
 221         }
 222
 223         /*
 224          *      Normal socket close.
 225          */
 226         if (rcode == 0) goto do_close;
 227
 228         sock->ssn->dirty_in.used = rcode;
 229
 230         dump_hex("READ FROM SSL", sock->ssn->dirty_in.data, sock->ssn->dirty_in.used);
 231
 232         /*
 233          *      Catch attempts to use non-SSL.
 234          */
 235         if (doing_init && (sock->ssn->dirty_in.data[0] != handshake)) {
 236                 RDEBUG("Non-TLS data sent to TLS socket: closing");
 237                 goto do_close;
 238         }
 239
 240         /*
 241          *      Skip ahead to reading application data.
 242          */
 243         if (SSL_is_init_finished(sock->ssn->ssl)) goto app;
 244
 245         if (!tls_handshake_recv(request, sock->ssn)) {
 246                 RDEBUG("FAILED in TLS handshake receive");
 247                 goto do_close;
 248         }
 249
 250         if (sock->ssn->dirty_out.used > 0) {
 251                 tls_socket_write(listener, request);
 252                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 253                 return 0;
 254         }
 255
 256 app:
 257         /*
 258          *      FIXME: Run the packet through a virtual server in
 259          *      order to see if we like the certificate presented by
 260          *      the client.
 261          */
 262
 263         status = tls_application_data(sock->ssn, request);
 264         RDEBUG("Application data status %d", status);
 265
 266         if (status == FR_TLS_MORE_FRAGMENTS) {
 267                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 268                 return 0;
 269         }
 270
 271         if (sock->ssn->clean_out.used == 0) {
 272                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 273                 return 0;
 274         }
 275
 276         dump_hex("TUNNELED DATA", sock->ssn->clean_out.data, sock->ssn->clean_out.used);
 277
 278         /*
 279          *      If the packet is a complete RADIUS packet, return it to
 280          *      the caller.  Otherwise...
 281          */
 282         if ((sock->ssn->clean_out.used < 20) ||
 283             (((sock->ssn->clean_out.data[2] << 8) | sock->ssn->clean_out.data[3]) != (int) sock->ssn->clean_out.used)) {
 284                 RDEBUG("Received bad packet: Length %d contents %d",
 285                        sock->ssn->clean_out.used,
 286                        (sock->ssn->clean_out.data[2] << 8) | sock->ssn->clean_out.data[3]);
 287                 goto do_close;
 288         }
 289
 290         packet = sock->packet;
 291         packet->data = rad_malloc(sock->ssn->clean_out.used);
 292         packet->data_len = sock->ssn->clean_out.used;
 293         sock->ssn->record_minus(&sock->ssn->clean_out, packet->data, packet->data_len);
 294         packet->vps = NULL;
 295         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 296
 297         if (!rad_packet_ok(packet, 0)) {
 298                 RDEBUG("Received bad packet: %s", fr_strerror());
 299                 tls_socket_close(listener);
 300                 return 0;       /* do_close unlocks the mutex */
 301         }
 302
 303         /*
 304          *      Copied from src/lib/radius.c, rad_recv();
 305          */
 306         if (fr_debug_flag) {
 307                 char host_ipaddr[128];
 308
 309                 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
 310                         RDEBUG("tls_recv: %s packet from host %s port %d, id=%d, length=%d",
 311                                fr_packet_codes[packet->code],
 312                                inet_ntop(packet->src_ipaddr.af,
 313                                          &packet->src_ipaddr.ipaddr,
 314                                          host_ipaddr, sizeof(host_ipaddr)),
 315                                packet->src_port,
 316                                packet->id, (int) packet->data_len);
 317                 } else {
 318                         RDEBUG("tls_recv: Packet from host %s port %d code=%d, id=%d, length=%d",
 319                                inet_ntop(packet->src_ipaddr.af,
 320                                          &packet->src_ipaddr.ipaddr,
 321                                          host_ipaddr, sizeof(host_ipaddr)),
 322                                packet->src_port,
 323                                packet->code,
 324                                packet->id, (int) packet->data_len);
 325                 }
 326         }
 327
 328         FR_STATS_INC(auth, total_requests);
 329
 330         return 1;
 331 }
 332
 333
 334 int dual_tls_recv(rad_listen_t *listener)
 335 {
 336         RADIUS_PACKET *packet;
 337         REQUEST *request;
 338         RAD_REQUEST_FUNP fun = NULL;
 339         listen_socket_t *sock = listener->data;
 340         RADCLIENT       *client = sock->client;
 341
 342         if (!tls_socket_recv(listener)) {
 343                 return 0;
 344         }
 345
 346         rad_assert(sock->request != NULL);
 347         rad_assert(sock->request->packet != NULL);
 348         rad_assert(sock->packet != NULL);
 349         rad_assert(sock->ssn != NULL);
 350
 351         request = sock->request;
 352         packet = sock->packet;
 353
 354         /*
 355          *      Some sanity checks, based on the packet code.
 356          */
 357         switch(packet->code) {
 358         case PW_AUTHENTICATION_REQUEST:
 359                 if (listener->type != RAD_LISTEN_AUTH) goto bad_packet;
 360                 FR_STATS_INC(auth, total_requests);
 361                 fun = rad_authenticate;
 362                 break;
 363
 364         case PW_ACCOUNTING_REQUEST:
 365                 if (listener->type != RAD_LISTEN_ACCT) goto bad_packet;
 366                 FR_STATS_INC(acct, total_requests);
 367                 fun = rad_accounting;
 368                 break;
 369
 370         case PW_STATUS_SERVER:
 371                 if (!mainconfig.status_server) {
 372                         FR_STATS_INC(auth, total_unknown_types);
 373                         DEBUGW("Ignoring Status-Server request due to security configuration");
 374                         rad_free(&sock->packet);
 375                         request->packet = NULL;
 376                         return 0;
 377                 }
 378                 fun = rad_status_server;
 379                 break;
 380
 381         default:
 382         bad_packet:
 383                 FR_STATS_INC(auth, total_unknown_types);
 384
 385                 DEBUG("Invalid packet code %d sent from client %s port %d : IGNORED",
 386                       packet->code, client->shortname, packet->src_port);
 387                 rad_free(&sock->packet);
 388                 request->packet = NULL;
 389                 return 0;
 390         } /* switch over packet types */
 391
 392         if (!request_receive(listener, packet, client, fun)) {
 393                 FR_STATS_INC(auth, total_packets_dropped);
 394                 rad_free(&sock->packet);
 395                 request->packet = NULL;
 396                 return 0;
 397         }
 398
 399         sock->packet = NULL;    /* we have no need for more partial reads */
 400         request->packet = NULL;
 401
 402         return 1;
 403 }
 404
 405
 406 /*
 407  *      Send a response packet
 408  */
 409 int dual_tls_send(rad_listen_t *listener, REQUEST *request)
 410 {
 411         listen_socket_t *sock = listener->data;
 412
 413         rad_assert(request->listener == listener);
 414         rad_assert(listener->send == dual_tls_send);
 415
 416         /*
 417          *      Accounting reject's are silently dropped.
 418          *
 419          *      We do it here to avoid polluting the rest of the
 420          *      code with this knowledge
 421          */
 422         if (request->reply->code == 0) return 0;
 423
 424         /*
 425          *      Pack the VPs
 426          */
 427         if (rad_encode(request->reply, request->packet,
 428                        request->client->secret) < 0) {
 429                 RDEBUG("Failed encoding packet: %s", fr_strerror());
 430                 return 0;
 431         }
 432
 433         /*
 434          *      Sign the packet.
 435          */
 436         if (rad_sign(request->reply, request->packet,
 437                        request->client->secret) < 0) {
 438                 RDEBUG("Failed signing packet: %s", fr_strerror());
 439                 return 0;
 440         }
 441
 442         PTHREAD_MUTEX_LOCK(&sock->mutex);
 443         /*
 444          *      Write the packet to the SSL buffers.
 445          */
 446         sock->ssn->record_plus(&sock->ssn->clean_in,
 447                                request->reply->data, request->reply->data_len);
 448
 449         /*
 450          *      Do SSL magic to get encrypted data.
 451          */
 452         tls_handshake_send(request, sock->ssn);
 453
 454         /*
 455          *      And finally write the data to the socket.
 456          */
 457         if (sock->ssn->dirty_out.used > 0) {
 458                 dump_hex("WRITE TO SSL", sock->ssn->dirty_out.data, sock->ssn->dirty_out.used);
 459
 460                 tls_socket_write(listener, request);
 461         }
 462         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 463
 464         return 0;
 465 }
 466
 467
 468 int proxy_tls_recv(rad_listen_t *listener)
 469 {
 470         int rcode;
 471         size_t length;
 472         listen_socket_t *sock = listener->data;
 473         char buffer[256];
 474         RADIUS_PACKET *packet;
 475         uint8_t *data;
 476
 477         if (!sock->data) sock->data = rad_malloc(sock->ssn->offset);
 478         data = sock->data;
 479
 480         DEBUG3("Proxy SSL socket has data to read");
 481         PTHREAD_MUTEX_LOCK(&sock->mutex);
 482 redo:
 483         rcode = SSL_read(sock->ssn->ssl, data, 4);
 484         if (rcode <= 0) {
 485                 int err = SSL_get_error(sock->ssn->ssl, rcode);
 486                 switch (err) {
 487                 case SSL_ERROR_WANT_READ:
 488                 case SSL_ERROR_WANT_WRITE:
 489                         goto redo;
 490
 491                 case SSL_ERROR_ZERO_RETURN:
 492                         /* remote end sent close_notify, send one back */
 493                         SSL_shutdown(sock->ssn->ssl);
 494
 495                 case SSL_ERROR_SYSCALL:
 496                 do_close:
 497                         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 498                         tls_socket_close(listener);
 499                         return 0;
 500
 501                 default:
 502                         while ((err = ERR_get_error())) {
 503                                 DEBUG("proxy recv says %s",
 504                                       ERR_error_string(err, NULL));
 505                         }
 506
 507                         goto do_close;
 508                 }
 509         }
 510
 511         length = (data[2] << 8) | data[3];
 512         DEBUG3("Proxy received header saying we have a packet of %u bytes",
 513                (unsigned int) length);
 514
 515         if (length > sock->ssn->offset) {
 516                 radlog(L_INFO,
 517                        "Received packet will be too large! Set \"fragment_size=%u\"",
 518                        (data[2] << 8) | data[3]);
 519                 goto do_close;
 520         }
 521
 522         rcode = SSL_read(sock->ssn->ssl, data + 4, length);
 523         if (rcode <= 0) {
 524                 switch (SSL_get_error(sock->ssn->ssl, rcode)) {
 525                 case SSL_ERROR_WANT_READ:
 526                 case SSL_ERROR_WANT_WRITE:
 527                         break;
 528
 529                 case SSL_ERROR_ZERO_RETURN:
 530                         /* remote end sent close_notify, send one back */
 531                         SSL_shutdown(sock->ssn->ssl);
 532                         goto do_close;
 533                 default:
 534                         goto do_close;
 535                 }
 536         }
 537         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 538
 539         packet = rad_alloc(NULL, 0);
 540         packet->sockfd = listener->fd;
 541         packet->src_ipaddr = sock->other_ipaddr;
 542         packet->src_port = sock->other_port;
 543         packet->dst_ipaddr = sock->my_ipaddr;
 544         packet->dst_port = sock->my_port;
 545         packet->code = data[0];
 546         packet->id = data[1];
 547         packet->data_len = length;
 548         packet->data = rad_malloc(packet->data_len);
 549         memcpy(packet->data, data, packet->data_len);
 550         memcpy(packet->vector, packet->data + 4, 16);
 551
 552         /*
 553          *      FIXME: Client MIB updates?
 554          */
 555         switch(packet->code) {
 556         case PW_AUTHENTICATION_ACK:
 557         case PW_ACCESS_CHALLENGE:
 558         case PW_AUTHENTICATION_REJECT:
 559                 break;
 560
 561 #ifdef WITH_ACCOUNTING
 562         case PW_ACCOUNTING_RESPONSE:
 563                 break;
 564 #endif
 565
 566         default:
 567                 /*
 568                  *      FIXME: Update MIB for packet types?
 569                  */
 570                 radlog(L_ERR, "Invalid packet code %d sent to a proxy port "
 571                        "from home server %s port %d - ID %d : IGNORED",
 572                        packet->code,
 573                        ip_ntoh(&packet->src_ipaddr, buffer, sizeof(buffer)),
 574                        packet->src_port, packet->id);
 575                 rad_free(&packet);
 576                 return 0;
 577         }
 578
 579         if (!request_proxy_reply(packet)) {
 580                 rad_free(&packet);
 581                 return 0;
 582         }
 583
 584         return 1;
 585 }
 586
 587 int proxy_tls_send(rad_listen_t *listener, REQUEST *request)
 588 {
 589         int rcode;
 590         listen_socket_t *sock = listener->data;
 591
 592         /*
 593          *      Normal proxying calls us with the data already
 594          *      encoded.  The "ping home server" code does not.  So,
 595          *      if there's no packet, encode it here.
 596          */
 597         if (!request->proxy->data) {
 598                 request->proxy_listener->encode(request->proxy_listener,
 599                                                 request);
 600         }
 601
 602         DEBUG3("Proxy is writing %u bytes to SSL",
 603                (unsigned int) request->proxy->data_len);
 604         PTHREAD_MUTEX_LOCK(&sock->mutex);
 605         while ((rcode = SSL_write(sock->ssn->ssl, request->proxy->data,
 606                                   request->proxy->data_len)) < 0) {
 607                 int err;
 608                 while ((err = ERR_get_error())) {
 609                         DEBUG("proxy SSL_write says %s",
 610                               ERR_error_string(err, NULL));
 611                 }
 612                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 613                 tls_socket_close(listener);
 614                 return 0;
 615         }
 616         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 617
 618         return 1;
 619 }
 620
 621 #endif  /* WITH_TLS */