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         memset(sock->ssn->dirty_in.data + sock->ssn->dirty_in.used,
 227                0, 16);
 228
 229         dump_hex("READ FROM SSL", sock->ssn->dirty_in.data, sock->ssn->dirty_in.used);
 230
 231         /*
 232          *      Catch attempts to use non-SSL.
 233          */
 234         if (doing_init && (sock->ssn->dirty_in.data[0] != handshake)) {
 235                 RDEBUG("Non-TLS data sent to TLS socket: closing");
 236                 goto do_close;
 237         }
 238
 239         /*
 240          *      Skip ahead to reading application data.
 241          */
 242         if (SSL_is_init_finished(sock->ssn->ssl)) goto app;
 243
 244         if (!tls_handshake_recv(request, sock->ssn)) {
 245                 RDEBUG("FAILED in TLS handshake receive");
 246                 goto do_close;
 247         }
 248
 249         if (sock->ssn->dirty_out.used > 0) {
 250                 tls_socket_write(listener, request);
 251                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 252                 return 0;
 253         }
 254
 255 app:
 256         /*
 257          *      FIXME: Run the packet through a virtual server in
 258          *      order to see if we like the certificate presented by
 259          *      the client.
 260          */
 261
 262         status = tls_application_data(sock->ssn, request);
 263         RDEBUG("Application data status %d", status);
 264
 265         if (status == FR_TLS_MORE_FRAGMENTS) {
 266                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 267                 return 0;
 268         }
 269
 270         if (sock->ssn->clean_out.used == 0) {
 271                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 272                 return 0;
 273         }
 274
 275         dump_hex("TUNNELED DATA", sock->ssn->clean_out.data, sock->ssn->clean_out.used);
 276
 277         /*
 278          *      If the packet is a complete RADIUS packet, return it to
 279          *      the caller.  Otherwise...
 280          */
 281         if ((sock->ssn->clean_out.used < 20) ||
 282             (((sock->ssn->clean_out.data[2] << 8) | sock->ssn->clean_out.data[3]) != (int) sock->ssn->clean_out.used)) {
 283                 RDEBUG("Received bad packet: Length %d contents %d",
 284                        sock->ssn->clean_out.used,
 285                        (sock->ssn->clean_out.data[2] << 8) | sock->ssn->clean_out.data[3]);
 286                 goto do_close;
 287         }
 288
 289         packet = sock->packet;
 290         packet->data = rad_malloc(sock->ssn->clean_out.used);
 291         packet->data_len = sock->ssn->clean_out.used;
 292         sock->ssn->record_minus(&sock->ssn->clean_out, packet->data, packet->data_len);
 293         packet->vps = NULL;
 294         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 295
 296         if (!rad_packet_ok(packet, 0)) {
 297                 RDEBUG("Received bad packet: %s", fr_strerror());
 298                 tls_socket_close(listener);
 299                 return 0;       /* do_close unlocks the mutex */
 300         }
 301
 302         /*
 303          *      Copied from src/lib/radius.c, rad_recv();
 304          */
 305         if (fr_debug_flag) {
 306                 char host_ipaddr[128];
 307
 308                 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
 309                         RDEBUG("tls_recv: %s packet from host %s port %d, id=%d, length=%d",
 310                                fr_packet_codes[packet->code],
 311                                inet_ntop(packet->src_ipaddr.af,
 312                                          &packet->src_ipaddr.ipaddr,
 313                                          host_ipaddr, sizeof(host_ipaddr)),
 314                                packet->src_port,
 315                                packet->id, (int) packet->data_len);
 316                 } else {
 317                         RDEBUG("tls_recv: Packet from host %s port %d code=%d, id=%d, length=%d",
 318                                inet_ntop(packet->src_ipaddr.af,
 319                                          &packet->src_ipaddr.ipaddr,
 320                                          host_ipaddr, sizeof(host_ipaddr)),
 321                                packet->src_port,
 322                                packet->code,
 323                                packet->id, (int) packet->data_len);
 324                 }
 325         }
 326
 327         FR_STATS_INC(auth, total_requests);
 328
 329         return 1;
 330 }
 331
 332
 333 int dual_tls_recv(rad_listen_t *listener)
 334 {
 335         RADIUS_PACKET *packet;
 336         REQUEST *request;
 337         RAD_REQUEST_FUNP fun = NULL;
 338         listen_socket_t *sock = listener->data;
 339         RADCLIENT       *client = sock->client;
 340
 341         if (!tls_socket_recv(listener)) {
 342                 return 0;
 343         }
 344
 345         rad_assert(sock->request != NULL);
 346         rad_assert(sock->request->packet != NULL);
 347         rad_assert(sock->packet != NULL);
 348         rad_assert(sock->ssn != NULL);
 349
 350         request = sock->request;
 351         packet = sock->packet;
 352
 353         /*
 354          *      Some sanity checks, based on the packet code.
 355          */
 356         switch(packet->code) {
 357         case PW_AUTHENTICATION_REQUEST:
 358                 if (listener->type != RAD_LISTEN_AUTH) goto bad_packet;
 359                 FR_STATS_INC(auth, total_requests);
 360                 fun = rad_authenticate;
 361                 break;
 362
 363         case PW_ACCOUNTING_REQUEST:
 364                 if (listener->type != RAD_LISTEN_ACCT) goto bad_packet;
 365                 FR_STATS_INC(acct, total_requests);
 366                 fun = rad_accounting;
 367                 break;
 368
 369         case PW_STATUS_SERVER:
 370                 if (!mainconfig.status_server) {
 371                         FR_STATS_INC(auth, total_unknown_types);
 372                         DEBUG("WARNING: Ignoring Status-Server request due to security configuration");
 373                         rad_free(&sock->packet);
 374                         request->packet = NULL;
 375                         return 0;
 376                 }
 377                 fun = rad_status_server;
 378                 break;
 379
 380         default:
 381         bad_packet:
 382                 FR_STATS_INC(auth, total_unknown_types);
 383
 384                 DEBUG("Invalid packet code %d sent from client %s port %d : IGNORED",
 385                       packet->code, client->shortname, packet->src_port);
 386                 rad_free(&sock->packet);
 387                 request->packet = NULL;
 388                 return 0;
 389         } /* switch over packet types */
 390
 391         if (!request_receive(listener, packet, client, fun)) {
 392                 FR_STATS_INC(auth, total_packets_dropped);
 393                 rad_free(&sock->packet);
 394                 request->packet = NULL;
 395                 return 0;
 396         }
 397
 398         sock->packet = NULL;    /* we have no need for more partial reads */
 399         request->packet = NULL;
 400
 401         return 1;
 402 }
 403
 404
 405 /*
 406  *      Send a response packet
 407  */
 408 int dual_tls_send(rad_listen_t *listener, REQUEST *request)
 409 {
 410         listen_socket_t *sock = listener->data;
 411
 412         rad_assert(request->listener == listener);
 413         rad_assert(listener->send == dual_tls_send);
 414
 415         /*
 416          *      Accounting reject's are silently dropped.
 417          *
 418          *      We do it here to avoid polluting the rest of the
 419          *      code with this knowledge
 420          */
 421         if (request->reply->code == 0) return 0;
 422
 423         /*
 424          *      Pack the VPs
 425          */
 426         if (rad_encode(request->reply, request->packet,
 427                        request->client->secret) < 0) {
 428                 RDEBUG("Failed encoding packet: %s", fr_strerror());
 429                 return 0;
 430         }
 431
 432         /*
 433          *      Sign the packet.
 434          */
 435         if (rad_sign(request->reply, request->packet,
 436                        request->client->secret) < 0) {
 437                 RDEBUG("Failed signing packet: %s", fr_strerror());
 438                 return 0;
 439         }
 440
 441         PTHREAD_MUTEX_LOCK(&sock->mutex);
 442         /*
 443          *      Write the packet to the SSL buffers.
 444          */
 445         sock->ssn->record_plus(&sock->ssn->clean_in,
 446                                request->reply->data, request->reply->data_len);
 447
 448         /*
 449          *      Do SSL magic to get encrypted data.
 450          */
 451         tls_handshake_send(request, sock->ssn);
 452
 453         /*
 454          *      And finally write the data to the socket.
 455          */
 456         if (sock->ssn->dirty_out.used > 0) {
 457                 dump_hex("WRITE TO SSL", sock->ssn->dirty_out.data, sock->ssn->dirty_out.used);
 458
 459                 tls_socket_write(listener, request);
 460         }
 461         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 462
 463         return 0;
 464 }
 465
 466
 467 int proxy_tls_recv(rad_listen_t *listener)
 468 {
 469         int rcode;
 470         size_t length;
 471         listen_socket_t *sock = listener->data;
 472         char buffer[256];
 473         RADIUS_PACKET *packet;
 474         uint8_t *data;
 475
 476         if (!sock->data) sock->data = rad_malloc(sock->ssn->offset);
 477         data = sock->data;
 478
 479         DEBUG3("Proxy SSL socket has data to read");
 480         PTHREAD_MUTEX_LOCK(&sock->mutex);
 481 redo:
 482         rcode = SSL_read(sock->ssn->ssl, data, 4);
 483         if (rcode <= 0) {
 484                 int err = SSL_get_error(sock->ssn->ssl, rcode);
 485                 switch (err) {
 486                 case SSL_ERROR_WANT_READ:
 487                 case SSL_ERROR_WANT_WRITE:
 488                         goto redo;
 489
 490                 case SSL_ERROR_ZERO_RETURN:
 491                         /* remote end sent close_notify, send one back */
 492                         SSL_shutdown(sock->ssn->ssl);
 493
 494                 case SSL_ERROR_SYSCALL:
 495                 do_close:
 496                         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 497                         tls_socket_close(listener);
 498                         return 0;
 499
 500                 default:
 501                         while ((err = ERR_get_error())) {
 502                                 DEBUG("proxy recv says %s",
 503                                       ERR_error_string(err, NULL));
 504                         }
 505
 506                         goto do_close;
 507                 }
 508         }
 509
 510         length = (data[2] << 8) | data[3];
 511         DEBUG3("Proxy received header saying we have a packet of %u bytes",
 512                (unsigned int) length);
 513
 514         if (length > sock->ssn->offset) {
 515                 radlog(L_INFO,
 516                        "Received packet will be too large! Set \"fragment_size=%u\"",
 517                        (data[2] << 8) | data[3]);
 518                 goto do_close;
 519         }
 520
 521         rcode = SSL_read(sock->ssn->ssl, data + 4, length);
 522         if (rcode <= 0) {
 523                 switch (SSL_get_error(sock->ssn->ssl, rcode)) {
 524                 case SSL_ERROR_WANT_READ:
 525                 case SSL_ERROR_WANT_WRITE:
 526                         break;
 527
 528                 case SSL_ERROR_ZERO_RETURN:
 529                         /* remote end sent close_notify, send one back */
 530                         SSL_shutdown(sock->ssn->ssl);
 531                         goto do_close;
 532                 default:
 533                         goto do_close;
 534                 }
 535         }
 536         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 537
 538         packet = rad_alloc(0);
 539         packet->sockfd = listener->fd;
 540         packet->src_ipaddr = sock->other_ipaddr;
 541         packet->src_port = sock->other_port;
 542         packet->dst_ipaddr = sock->my_ipaddr;
 543         packet->dst_port = sock->my_port;
 544         packet->code = data[0];
 545         packet->id = data[1];
 546         packet->data_len = length;
 547         packet->data = rad_malloc(packet->data_len);
 548         memcpy(packet->data, data, packet->data_len);
 549         memcpy(packet->vector, packet->data + 4, 16);
 550
 551         /*
 552          *      FIXME: Client MIB updates?
 553          */
 554         switch(packet->code) {
 555         case PW_AUTHENTICATION_ACK:
 556         case PW_ACCESS_CHALLENGE:
 557         case PW_AUTHENTICATION_REJECT:
 558                 break;
 559
 560 #ifdef WITH_ACCOUNTING
 561         case PW_ACCOUNTING_RESPONSE:
 562                 break;
 563 #endif
 564
 565         default:
 566                 /*
 567                  *      FIXME: Update MIB for packet types?
 568                  */
 569                 radlog(L_ERR, "Invalid packet code %d sent to a proxy port "
 570                        "from home server %s port %d - ID %d : IGNORED",
 571                        packet->code,
 572                        ip_ntoh(&packet->src_ipaddr, buffer, sizeof(buffer)),
 573                        packet->src_port, packet->id);
 574                 rad_free(&packet);
 575                 return 0;
 576         }
 577
 578         if (!request_proxy_reply(packet)) {
 579                 rad_free(&packet);
 580                 return 0;
 581         }
 582
 583         return 1;
 584 }
 585
 586 int proxy_tls_send(rad_listen_t *listener, REQUEST *request)
 587 {
 588         int rcode;
 589         listen_socket_t *sock = listener->data;
 590
 591         /*
 592          *      Normal proxying calls us with the data already
 593          *      encoded.  The "ping home server" code does not.  So,
 594          *      if there's no packet, encode it here.
 595          */
 596         if (!request->proxy->data) {
 597                 request->proxy_listener->encode(request->proxy_listener,
 598                                                 request);
 599         }
 600
 601         DEBUG3("Proxy is writing %u bytes to SSL",
 602                (unsigned int) request->proxy->data_len);
 603         PTHREAD_MUTEX_LOCK(&sock->mutex);
 604         while ((rcode = SSL_write(sock->ssn->ssl, request->proxy->data,
 605                                   request->proxy->data_len)) < 0) {
 606                 int err;
 607                 while ((err = ERR_get_error())) {
 608                         DEBUG("proxy SSL_write says %s",
 609                               ERR_error_string(err, NULL));
 610                 }
 611                 PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 612                 tls_socket_close(listener);
 613                 return 0;
 614         }
 615         PTHREAD_MUTEX_UNLOCK(&sock->mutex);
 616
 617         return 1;
 618 }
 619
 620 #endif  /* WITH_TLS */