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(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) sock->request->packet = sock->packet;
 153         }
 154
 155         /*
 156          *      Allocate a REQUEST for debugging.
 157          */
 158         if (!sock->request) {
 159                 sock->request = request = request_alloc();
 160                 if (!sock->request) {
 161                         radlog(L_ERR, "Out of memory");
 162                         return 0;
 163                 }
 164
 165                 rad_assert(request->packet == NULL);
 166                 rad_assert(sock->packet != NULL);
 167                 request->packet = sock->packet;
 168
 169                 request->component = "<core>";
 170                 request->component = "<tls-connect>";
 171
 172                 /*
 173                  *      Not sure if we should do this on every packet...
 174                  */
 175                 request->reply = rad_alloc(0);
 176                 if (!request->reply) return 0;
 177
 178                 request->options = RAD_REQUEST_OPTION_DEBUG2;
 179
 180                 rad_assert(sock->ssn == NULL);
 181
 182                 sock->ssn = tls_new_session(listener->tls, sock->request,
 183                                             listener->tls->require_client_cert);
 184                 if (!sock->ssn) {
 185                         request_free(&sock->request);
 186                         sock->packet = NULL;
 187                         return 0;
 188                 }
 189
 190                 SSL_set_ex_data(sock->ssn->ssl, FR_TLS_EX_INDEX_REQUEST, (void *)request);
 191                 SSL_set_ex_data(sock->ssn->ssl, FR_TLS_EX_INDEX_CERTS, (void *)&request->packet->vps);
 192
 193                 doing_init = TRUE;
 194         }
 195
 196         rad_assert(sock->request != NULL);
 197         rad_assert(sock->request->packet != NULL);
 198         rad_assert(sock->packet != NULL);
 199         rad_assert(sock->ssn != NULL);
 200
 201         request = sock->request;
 202
 203         RDEBUG3("Reading from socket %d", request->packet->sockfd);
 204         PTHREAD_MUTEX_LOCK(&sock->mutex);
 205         rcode = read(request->packet->sockfd,
 206                      sock->ssn->dirty_in.data,
 207                      sizeof(sock->ssn->dirty_in.data));
 208         if ((rcode < 0) && (errno == ECONNRESET)) {
 209         do_close:
 210                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 211                 tls_socket_close(listener);
 212                 return 0;
 213         }
 214
 215         if (rcode < 0) {
 216                 RDEBUG("Error reading TLS socket: %s", strerror(errno));
 217                 goto do_close;
 218         }
 219
 220         /*
 221          *      Normal socket close.
 222          */
 223         if (rcode == 0) goto do_close;
 224
 225         sock->ssn->dirty_in.used = rcode;
 226
 227         dump_hex("READ FROM SSL", sock->ssn->dirty_in.data, sock->ssn->dirty_in.used);
 228
 229         /*
 230          *      Catch attempts to use non-SSL.
 231          */
 232         if (doing_init && (sock->ssn->dirty_in.data[0] != handshake)) {
 233                 RDEBUG("Non-TLS data sent to TLS socket: closing");
 234                 goto do_close;
 235         }
 236
 237         /*
 238          *      Skip ahead to reading application data.
 239          */
 240         if (SSL_is_init_finished(sock->ssn->ssl)) goto app;
 241
 242         if (!tls_handshake_recv(request, sock->ssn)) {
 243                 RDEBUG("FAILED in TLS handshake receive");
 244                 goto do_close;
 245         }
 246
 247         if (sock->ssn->dirty_out.used > 0) {
 248                 tls_socket_write(listener, request);
 249                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 250                 return 0;
 251         }
 252
 253 app:
 254         /*
 255          *      FIXME: Run the packet through a virtual server in
 256          *      order to see if we like the certificate presented by
 257          *      the client.
 258          */
 259
 260         status = tls_application_data(sock->ssn, request);
 261         RDEBUG("Application data status %d", status);
 262
 263         if (status == FR_TLS_MORE_FRAGMENTS) {
 264                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 265                 return 0;
 266         }
 267
 268         if (sock->ssn->clean_out.used == 0) {
 269                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 270                 return 0;
 271         }
 272
 273         dump_hex("TUNNELED DATA", sock->ssn->clean_out.data, sock->ssn->clean_out.used);
 274
 275         /*
 276          *      If the packet is a complete RADIUS packet, return it to
 277          *      the caller.  Otherwise...
 278          */
 279         if ((sock->ssn->clean_out.used < 20) ||
 280             (((sock->ssn->clean_out.data[2] << 8) | sock->ssn->clean_out.data[3]) != (int) sock->ssn->clean_out.used)) {
 281                 RDEBUG("Received bad packet: Length %d contents %d",
 282                        sock->ssn->clean_out.used,
 283                        (sock->ssn->clean_out.data[2] << 8) | sock->ssn->clean_out.data[3]);
 284                 goto do_close;
 285         }
 286
 287         packet = sock->packet;
 288         packet->data = rad_malloc(sock->ssn->clean_out.used);
 289         packet->data_len = sock->ssn->clean_out.used;
 290         sock->ssn->record_minus(&sock->ssn->clean_out, packet->data, packet->data_len);
 291         packet->vps = NULL;
 292         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 293
 294         if (!rad_packet_ok(packet, 0)) {
 295                 RDEBUG("Received bad packet: %s", fr_strerror());
 296                 tls_socket_close(listener);
 297                 return 0;       /* do_close unlocks the mutex */
 298         }
 299
 300         /*
 301          *      Copied from src/lib/radius.c, rad_recv();
 302          */
 303         if (fr_debug_flag) {
 304                 char host_ipaddr[128];
 305
 306                 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
 307                         RDEBUG("tls_recv: %s packet from host %s port %d, id=%d, length=%d",
 308                                fr_packet_codes[packet->code],
 309                                inet_ntop(packet->src_ipaddr.af,
 310                                          &packet->src_ipaddr.ipaddr,
 311                                          host_ipaddr, sizeof(host_ipaddr)),
 312                                packet->src_port,
 313                                packet->id, (int) packet->data_len);
 314                 } else {
 315                         RDEBUG("tls_recv: Packet from host %s port %d code=%d, id=%d, length=%d",
 316                                inet_ntop(packet->src_ipaddr.af,
 317                                          &packet->src_ipaddr.ipaddr,
 318                                          host_ipaddr, sizeof(host_ipaddr)),
 319                                packet->src_port,
 320                                packet->code,
 321                                packet->id, (int) packet->data_len);
 322                 }
 323         }
 324
 325         FR_STATS_INC(auth, total_requests);
 326
 327         return 1;
 328 }
 329
 330
 331 int dual_tls_recv(rad_listen_t *listener)
 332 {
 333         RADIUS_PACKET *packet;
 334         REQUEST *request;
 335         RAD_REQUEST_FUNP fun = NULL;
 336         listen_socket_t *sock = listener->data;
 337         RADCLIENT       *client = sock->client;
 338
 339         if (!tls_socket_recv(listener)) {
 340                 return 0;
 341         }
 342
 343         rad_assert(sock->request != NULL);
 344         rad_assert(sock->request->packet != NULL);
 345         rad_assert(sock->packet != NULL);
 346         rad_assert(sock->ssn != NULL);
 347
 348         request = sock->request;
 349         packet = sock->packet;
 350
 351         /*
 352          *      Some sanity checks, based on the packet code.
 353          */
 354         switch(packet->code) {
 355         case PW_AUTHENTICATION_REQUEST:
 356                 if (listener->type != RAD_LISTEN_AUTH) goto bad_packet;
 357                 FR_STATS_INC(auth, total_requests);
 358                 fun = rad_authenticate;
 359                 break;
 360
 361         case PW_ACCOUNTING_REQUEST:
 362                 if (listener->type != RAD_LISTEN_ACCT) goto bad_packet;
 363                 FR_STATS_INC(acct, total_requests);
 364                 fun = rad_accounting;
 365                 break;
 366
 367         case PW_STATUS_SERVER:
 368                 if (!mainconfig.status_server) {
 369                         FR_STATS_INC(auth, total_unknown_types);
 370                         DEBUG("WARNING: Ignoring Status-Server request due to security configuration");
 371                         rad_free(&sock->packet);
 372                         request->packet = NULL;
 373                         return 0;
 374                 }
 375                 fun = rad_status_server;
 376                 break;
 377
 378         default:
 379         bad_packet:
 380                 FR_STATS_INC(auth, total_unknown_types);
 381
 382                 DEBUG("Invalid packet code %d sent from client %s port %d : IGNORED",
 383                       packet->code, client->shortname, packet->src_port);
 384                 rad_free(&sock->packet);
 385                 request->packet = NULL;
 386                 return 0;
 387         } /* switch over packet types */
 388
 389         if (!request_receive(listener, packet, client, fun)) {
 390                 FR_STATS_INC(auth, total_packets_dropped);
 391                 rad_free(&sock->packet);
 392                 request->packet = NULL;
 393                 return 0;
 394         }
 395
 396         sock->packet = NULL;    /* we have no need for more partial reads */
 397         request->packet = NULL;
 398
 399         return 1;
 400 }
 401
 402
 403 /*
 404  *      Send a response packet
 405  */
 406 int dual_tls_send(rad_listen_t *listener, REQUEST *request)
 407 {
 408         listen_socket_t *sock = listener->data;
 409
 410         rad_assert(request->listener == listener);
 411         rad_assert(listener->send == dual_tls_send);
 412
 413         /*
 414          *      Accounting reject's are silently dropped.
 415          *
 416          *      We do it here to avoid polluting the rest of the
 417          *      code with this knowledge
 418          */
 419         if (request->reply->code == 0) return 0;
 420
 421         /*
 422          *      Pack the VPs
 423          */
 424         if (rad_encode(request->reply, request->packet,
 425                        request->client->secret) < 0) {
 426                 RDEBUG("Failed encoding packet: %s", fr_strerror());
 427                 return 0;
 428         }
 429
 430         /*
 431          *      Sign the packet.
 432          */
 433         if (rad_sign(request->reply, request->packet,
 434                        request->client->secret) < 0) {
 435                 RDEBUG("Failed signing packet: %s", fr_strerror());
 436                 return 0;
 437         }
 438
 439         PTHREAD_MUTEX_LOCK(&sock->mutex);
 440         /*
 441          *      Write the packet to the SSL buffers.
 442          */
 443         sock->ssn->record_plus(&sock->ssn->clean_in,
 444                                request->reply->data, request->reply->data_len);
 445
 446         /*
 447          *      Do SSL magic to get encrypted data.
 448          */
 449         tls_handshake_send(request, sock->ssn);
 450
 451         /*
 452          *      And finally write the data to the socket.
 453          */
 454         if (sock->ssn->dirty_out.used > 0) {
 455                 dump_hex("WRITE TO SSL", sock->ssn->dirty_out.data, sock->ssn->dirty_out.used);
 456
 457                 tls_socket_write(listener, request);
 458         }
 459         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 460
 461         return 0;
 462 }
 463
 464
 465 int proxy_tls_recv(rad_listen_t *listener)
 466 {
 467         int rcode;
 468         size_t length;
 469         listen_socket_t *sock = listener->data;
 470         char buffer[256];
 471         RADIUS_PACKET *packet;
 472         uint8_t *data;
 473
 474         if (!sock->data) sock->data = rad_malloc(sock->ssn->offset);
 475         data = sock->data;
 476
 477         DEBUG3("Proxy SSL socket has data to read");
 478         PTHREAD_MUTEX_LOCK(&sock->mutex);
 479 redo:
 480         rcode = SSL_read(sock->ssn->ssl, data, 4);
 481         if (rcode <= 0) {
 482                 int err = SSL_get_error(sock->ssn->ssl, rcode);
 483                 switch (err) {
 484                 case SSL_ERROR_WANT_READ:
 485                 case SSL_ERROR_WANT_WRITE:
 486                         goto redo;
 487
 488                 case SSL_ERROR_ZERO_RETURN:
 489                         /* remote end sent close_notify, send one back */
 490                         SSL_shutdown(sock->ssn->ssl);
 491
 492                 case SSL_ERROR_SYSCALL:
 493                 do_close:
 494                         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 495                         tls_socket_close(listener);
 496                         return 0;
 497
 498                 default:
 499                         while ((err = ERR_get_error())) {
 500                                 DEBUG("proxy recv says %s",
 501                                       ERR_error_string(err, NULL));
 502                         }
 503
 504                         goto do_close;
 505                 }
 506         }
 507
 508         length = (data[2] << 8) | data[3];
 509         DEBUG3("Proxy received header saying we have a packet of %u bytes",
 510                (unsigned int) length);
 511
 512         if (length > sock->ssn->offset) {
 513                 radlog(L_INFO,
 514                        "Received packet will be too large! Set \"fragment_size=%u\"",
 515                        (data[2] << 8) | data[3]);
 516                 goto do_close;
 517         }
 518
 519         rcode = SSL_read(sock->ssn->ssl, data + 4, length);
 520         if (rcode <= 0) {
 521                 switch (SSL_get_error(sock->ssn->ssl, rcode)) {
 522                 case SSL_ERROR_WANT_READ:
 523                 case SSL_ERROR_WANT_WRITE:
 524                         break;
 525
 526                 case SSL_ERROR_ZERO_RETURN:
 527                         /* remote end sent close_notify, send one back */
 528                         SSL_shutdown(sock->ssn->ssl);
 529                         goto do_close;
 530                 default:
 531                         goto do_close;
 532                 }
 533         }
 534         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 535
 536         packet = rad_alloc(0);
 537         packet->sockfd = listener->fd;
 538         packet->src_ipaddr = sock->other_ipaddr;
 539         packet->src_port = sock->other_port;
 540         packet->dst_ipaddr = sock->my_ipaddr;
 541         packet->dst_port = sock->my_port;
 542         packet->code = data[0];
 543         packet->id = data[1];
 544         packet->data_len = length;
 545         packet->data = rad_malloc(packet->data_len);
 546         memcpy(packet->data, data, packet->data_len);
 547         memcpy(packet->vector, packet->data + 4, 16);
 548
 549         /*
 550          *      FIXME: Client MIB updates?
 551          */
 552         switch(packet->code) {
 553         case PW_AUTHENTICATION_ACK:
 554         case PW_ACCESS_CHALLENGE:
 555         case PW_AUTHENTICATION_REJECT:
 556                 break;
 557
 558 #ifdef WITH_ACCOUNTING
 559         case PW_ACCOUNTING_RESPONSE:
 560                 break;
 561 #endif
 562
 563         default:
 564                 /*
 565                  *      FIXME: Update MIB for packet types?
 566                  */
 567                 radlog(L_ERR, "Invalid packet code %d sent to a proxy port "
 568                        "from home server %s port %d - ID %d : IGNORED",
 569                        packet->code,
 570                        ip_ntoh(&packet->src_ipaddr, buffer, sizeof(buffer)),
 571                        packet->src_port, packet->id);
 572                 rad_free(&packet);
 573                 return 0;
 574         }
 575
 576         if (!request_proxy_reply(packet)) {
 577                 rad_free(&packet);
 578                 return 0;
 579         }
 580
 581         return 1;
 582 }
 583
 584 int proxy_tls_send(rad_listen_t *listener, REQUEST *request)
 585 {
 586         int rcode;
 587         listen_socket_t *sock = listener->data;
 588
 589         /*
 590          *      Normal proxying calls us with the data already
 591          *      encoded.  The "ping home server" code does not.  So,
 592          *      if there's no packet, encode it here.
 593          */
 594         if (!request->proxy->data) {
 595                 request->proxy_listener->encode(request->proxy_listener,
 596                                                 request);
 597         }
 598
 599         DEBUG3("Proxy is writing %u bytes to SSL",
 600                (unsigned int) request->proxy->data_len);
 601         PTHREAD_MUTEX_LOCK(&sock->mutex);
 602         while ((rcode = SSL_write(sock->ssn->ssl, request->proxy->data,
 603                                   request->proxy->data_len)) < 0) {
 604                 int err;
 605                 while ((err = ERR_get_error())) {
 606                         DEBUG("proxy SSL_write says %s",
 607                               ERR_error_string(err, NULL));
 608                 }
 609                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 610                 tls_socket_close(listener);
 611                 return 0;
 612         }
 613         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 614
 615         return 1;
 616 }
 617
 618 #endif  /* WITH_TLS */