_ Git - BearSSL/blob - tools/server.c

   1 /*
   2  * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining
   5  * a copy of this software and associated documentation files (the
   6  * "Software"), to deal in the Software without restriction, including
   7  * without limitation the rights to use, copy, modify, merge, publish,
   8  * distribute, sublicense, and/or sell copies of the Software, and to
   9  * permit persons to whom the Software is furnished to do so, subject to
  10  * the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be
  13  * included in all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  19  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  20  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  */
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <stdint.h>
  29 #include <errno.h>
  30
  31 #include <sys/types.h>
  32 #include <sys/socket.h>
  33 #include <netdb.h>
  34 #include <netinet/in.h>
  35 #include <arpa/inet.h>
  36 #include <unistd.h>
  37 #include <fcntl.h>
  38
  39 #include "brssl.h"
  40 #include "bearssl.h"
  41
  42 static int
  43 host_bind(const char *host, const char *port, int verbose)
  44 {
  45         struct addrinfo hints, *si, *p;
  46         int fd;
  47         int err;
  48
  49         memset(&hints, 0, sizeof hints);
  50         hints.ai_family = PF_UNSPEC;
  51         hints.ai_socktype = SOCK_STREAM;
  52         err = getaddrinfo(host, port, &hints, &si);
  53         if (err != 0) {
  54                 fprintf(stderr, "ERROR: getaddrinfo(): %s\n",
  55                         gai_strerror(err));
  56                 return -1;
  57         }
  58         fd = -1;
  59         for (p = si; p != NULL; p = p->ai_next) {
  60                 struct sockaddr *sa;
  61                 struct sockaddr_in sa4;
  62                 struct sockaddr_in6 sa6;
  63                 size_t sa_len;
  64                 void *addr;
  65                 int opt;
  66
  67                 sa = (struct sockaddr *)p->ai_addr;
  68                 if (sa->sa_family == AF_INET) {
  69                         sa4 = *(struct sockaddr_in *)sa;
  70                         sa = (struct sockaddr *)&sa4;
  71                         sa_len = sizeof sa4;
  72                         addr = &sa4.sin_addr;
  73                         if (host == NULL) {
  74                                 sa4.sin_addr.s_addr = INADDR_ANY;
  75                         }
  76                 } else if (sa->sa_family == AF_INET6) {
  77                         sa6 = *(struct sockaddr_in6 *)sa;
  78                         sa = (struct sockaddr *)&sa6;
  79                         sa_len = sizeof sa6;
  80                         addr = &sa6.sin6_addr;
  81                         if (host == NULL) {
  82                                 sa6.sin6_addr = in6addr_any;
  83                         }
  84                 } else {
  85                         addr = NULL;
  86                         sa_len = p->ai_addrlen;
  87                 }
  88                 if (verbose) {
  89                         char tmp[INET6_ADDRSTRLEN + 50];
  90
  91                         if (addr != NULL) {
  92                                 if (!inet_ntop(p->ai_family, addr,
  93                                         tmp, sizeof tmp))
  94                                 {
  95                                         strcpy(tmp, "<invalid>");
  96                                 }
  97                         } else {
  98                                 sprintf(tmp, "<unknown family: %d>",
  99                                         (int)sa->sa_family);
 100                         }
 101                         fprintf(stderr, "binding to: %s\n", tmp);
 102                 }
 103                 fd = socket(p->ai_family, p->ai_socktype, p->ai_protocol);
 104                 if (fd < 0) {
 105                         if (verbose) {
 106                                 perror("socket()");
 107                         }
 108                         continue;
 109                 }
 110                 opt = 1;
 111                 setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof opt);
 112                 opt = 0;
 113                 setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &opt, sizeof opt);
 114                 if (bind(fd, sa, sa_len) < 0) {
 115                         if (verbose) {
 116                                 perror("bind()");
 117                         }
 118                         close(fd);
 119                         continue;
 120                 }
 121                 break;
 122         }
 123         if (p == NULL) {
 124                 freeaddrinfo(si);
 125                 fprintf(stderr, "ERROR: failed to bind\n");
 126                 return -1;
 127         }
 128         freeaddrinfo(si);
 129         if (listen(fd, 5) < 0) {
 130                 if (verbose) {
 131                         perror("listen()");
 132                 }
 133                 close(fd);
 134                 return -1;
 135         }
 136         if (verbose) {
 137                 fprintf(stderr, "bound.\n");
 138         }
 139         return fd;
 140 }
 141
 142 static int
 143 accept_client(int server_fd, int verbose)
 144 {
 145         int fd;
 146         struct sockaddr sa;
 147         socklen_t sa_len;
 148
 149         sa_len = sizeof sa;
 150         fd = accept(server_fd, &sa, &sa_len);
 151         if (fd < 0) {
 152                 if (verbose) {
 153                         perror("accept()");
 154                 }
 155                 return -1;
 156         }
 157         if (verbose) {
 158                 char tmp[INET6_ADDRSTRLEN + 50];
 159                 const char *name;
 160
 161                 name = NULL;
 162                 switch (sa.sa_family) {
 163                 case AF_INET:
 164                         name = inet_ntop(AF_INET,
 165                                 &((struct sockaddr_in *)&sa)->sin_addr,
 166                                 tmp, sizeof tmp);
 167                         break;
 168                 case AF_INET6:
 169                         name = inet_ntop(AF_INET6,
 170                                 &((struct sockaddr_in6 *)&sa)->sin6_addr,
 171                                 tmp, sizeof tmp);
 172                         break;
 173                 }
 174                 if (name == NULL) {
 175                         sprintf(tmp, "<unknown: %lu>",
 176                                 (unsigned long)sa.sa_family);
 177                         name = tmp;
 178                 }
 179                 fprintf(stderr, "accepting connection from: %s\n", name);
 180         }
 181
 182         /*
 183          * We make the socket non-blocking, since we are going to use
 184          * poll() to organise I/O.
 185          */
 186         fcntl(fd, F_SETFL, O_NONBLOCK);
 187         return fd;
 188 }
 189
 190 static void
 191 usage_server(void)
 192 {
 193         fprintf(stderr,
 194 "usage: brssl server [ options ]\n");
 195         fprintf(stderr,
 196 "options:\n");
 197         fprintf(stderr,
 198 "   -q              suppress verbose messages\n");
 199         fprintf(stderr,
 200 "   -trace          activate extra debug messages (dump of all packets)\n");
 201         fprintf(stderr,
 202 "   -b name         bind to a specific address or host name\n");
 203         fprintf(stderr,
 204 "   -p port         bind to a specific port (default: 4433)\n");
 205         fprintf(stderr,
 206 "   -mono           use monodirectional buffering\n");
 207         fprintf(stderr,
 208 "   -buf length     set the I/O buffer length (in bytes)\n");
 209         fprintf(stderr,
 210 "   -cache length   set the session cache storage length (in bytes)\n");
 211         fprintf(stderr,
 212 "   -cert fname     read certificate chain from file 'fname'\n");
 213         fprintf(stderr,
 214 "   -key fname      read private key from file 'fname'\n");
 215         fprintf(stderr,
 216 "   -list           list supported names (protocols, algorithms...)\n");
 217         fprintf(stderr,
 218 "   -vmin name      set minimum supported version (default: TLS-1.0)\n");
 219         fprintf(stderr,
 220 "   -vmax name      set maximum supported version (default: TLS-1.2)\n");
 221         fprintf(stderr,
 222 "   -cs names       set list of supported cipher suites (comma-separated)\n");
 223         fprintf(stderr,
 224 "   -hf names       add support for some hash functions (comma-separated)\n");
 225         fprintf(stderr,
 226 "   -serverpref     enforce server's preferences for cipher suites\n");
 227         exit(EXIT_FAILURE);
 228 }
 229
 230 typedef struct {
 231         const br_ssl_server_policy_class *vtable;
 232         int verbose;
 233         br_x509_certificate *chain;
 234         size_t chain_len;
 235         int cert_signer_algo;
 236         private_key *sk;
 237 } policy_context;
 238
 239 static int
 240 get_cert_signer_algo(br_x509_certificate *xc)
 241 {
 242         br_x509_decoder_context dc;
 243         int err;
 244
 245         br_x509_decoder_init(&dc, 0, 0);
 246         br_x509_decoder_push(&dc, xc->data, xc->data_len);
 247         err = br_x509_decoder_last_error(&dc);
 248         if (err != 0) {
 249                 return -err;
 250         } else {
 251                 return br_x509_decoder_get_signer_key_type(&dc);
 252         }
 253 }
 254
 255 static int
 256 sp_choose(const br_ssl_server_policy_class **pctx,
 257         const br_ssl_server_context *cc,
 258         br_ssl_server_choices *choices)
 259 {
 260         policy_context *pc;
 261         const br_suite_translated *st;
 262         size_t u, st_num;
 263         unsigned chashes;
 264         int hash_id;
 265
 266         pc = (policy_context *)pctx;
 267         st = br_ssl_server_get_client_suites(cc, &st_num);
 268         chashes = br_ssl_server_get_client_hashes(cc);
 269         for (hash_id = 6; hash_id >= 2; hash_id --) {
 270                 if ((chashes >> hash_id) & 1) {
 271                         break;
 272                 }
 273         }
 274         if (pc->verbose) {
 275                 fprintf(stderr, "Client parameters:\n");
 276                 fprintf(stderr, "   Maximum version:      ");
 277                 switch (cc->client_max_version) {
 278                 case BR_SSL30:
 279                         fprintf(stderr, "SSL 3.0");
 280                         break;
 281                 case BR_TLS10:
 282                         fprintf(stderr, "TLS 1.0");
 283                         break;
 284                 case BR_TLS11:
 285                         fprintf(stderr, "TLS 1.1");
 286                         break;
 287                 case BR_TLS12:
 288                         fprintf(stderr, "TLS 1.2");
 289                         break;
 290                 default:
 291                         fprintf(stderr, "unknown (0x%04X)",
 292                                 (unsigned)cc->client_max_version);
 293                         break;
 294                 }
 295                 fprintf(stderr, "\n");
 296                 fprintf(stderr, "   Compatible cipher suites:\n");
 297                 for (u = 0; u < st_num; u ++) {
 298                         char csn[80];
 299
 300                         get_suite_name_ext(st[u][0], csn, sizeof csn);
 301                         fprintf(stderr, "      %s\n", csn);
 302                 }
 303                 fprintf(stderr, "   Common hash functions:");
 304                 for (u = 2; u <= 6; u ++) {
 305                         if ((chashes >> u) & 1) {
 306                                 int z;
 307
 308                                 switch (u) {
 309                                 case 3: z = 224; break;
 310                                 case 4: z = 256; break;
 311                                 case 5: z = 384; break;
 312                                 case 6: z = 512; break;
 313                                 default:
 314                                         z = 1;
 315                                         break;
 316                                 }
 317                                 fprintf(stderr, " sha%d", z);
 318                         }
 319                 }
 320                 fprintf(stderr, "\n");
 321         }
 322         for (u = 0; u < st_num; u ++) {
 323                 unsigned tt;
 324
 325                 tt = st[u][1];
 326                 switch (tt >> 12) {
 327                 case BR_SSLKEYX_RSA:
 328                         if (pc->sk->key_type == BR_KEYTYPE_RSA) {
 329                                 choices->cipher_suite = st[u][0];
 330                                 goto choose_ok;
 331                         }
 332                         break;
 333                 case BR_SSLKEYX_ECDHE_RSA:
 334                         if (pc->sk->key_type == BR_KEYTYPE_RSA) {
 335                                 choices->cipher_suite = st[u][0];
 336                                 if (cc->eng.session.version < BR_TLS12) {
 337                                         hash_id = 0;
 338                                 }
 339                                 choices->hash_id = hash_id;
 340                                 goto choose_ok;
 341                         }
 342                         break;
 343                 case BR_SSLKEYX_ECDHE_ECDSA:
 344                         if (pc->sk->key_type == BR_KEYTYPE_EC) {
 345                                 choices->cipher_suite = st[u][0];
 346                                 if (cc->eng.session.version < BR_TLS12) {
 347                                         hash_id = br_sha1_ID;
 348                                 }
 349                                 choices->hash_id = hash_id;
 350                                 goto choose_ok;
 351                         }
 352                         break;
 353                 case BR_SSLKEYX_ECDH_RSA:
 354                         if (pc->sk->key_type == BR_KEYTYPE_EC
 355                                 && pc->cert_signer_algo == BR_KEYTYPE_RSA)
 356                         {
 357                                 choices->cipher_suite = st[u][0];
 358                                 goto choose_ok;
 359                         }
 360                         break;
 361                 case BR_SSLKEYX_ECDH_ECDSA:
 362                         if (pc->sk->key_type == BR_KEYTYPE_EC
 363                                 && pc->cert_signer_algo == BR_KEYTYPE_EC)
 364                         {
 365                                 choices->cipher_suite = st[u][0];
 366                                 goto choose_ok;
 367                         }
 368                         break;
 369                 }
 370         }
 371         return 0;
 372
 373 choose_ok:
 374         choices->chain = pc->chain;
 375         choices->chain_len = pc->chain_len;
 376         if (pc->verbose) {
 377                 char csn[80];
 378
 379                 get_suite_name_ext(choices->cipher_suite, csn, sizeof csn);
 380                 fprintf(stderr, "Using: %s\n", csn);
 381         }
 382         return 1;
 383 }
 384
 385 static uint32_t
 386 sp_do_keyx(const br_ssl_server_policy_class **pctx,
 387         unsigned char *data, size_t len)
 388 {
 389         policy_context *pc;
 390
 391         pc = (policy_context *)pctx;
 392         switch (pc->sk->key_type) {
 393         case BR_KEYTYPE_RSA:
 394                 return br_rsa_ssl_decrypt(
 395                         &br_rsa_i31_private, &pc->sk->key.rsa,
 396                         data, len);
 397         case BR_KEYTYPE_EC:
 398                 return br_ec_prime_i31.mul(data, len, pc->sk->key.ec.x,
 399                         pc->sk->key.ec.xlen, pc->sk->key.ec.curve);
 400         default:
 401                 fprintf(stderr, "ERROR: unknown private key type (%d)\n",
 402                         (int)pc->sk->key_type);
 403                 return 0;
 404         }
 405 }
 406
 407 /*
 408  * OID for hash functions in RSA signatures.
 409  */
 410 static const unsigned char HASH_OID_SHA1[] = {
 411         0x05, 0x2B, 0x0E, 0x03, 0x02, 0x1A
 412 };
 413
 414 static const unsigned char HASH_OID_SHA224[] = {
 415         0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04
 416 };
 417
 418 static const unsigned char HASH_OID_SHA256[] = {
 419         0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01
 420 };
 421
 422 static const unsigned char HASH_OID_SHA384[] = {
 423         0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02
 424 };
 425
 426 static const unsigned char HASH_OID_SHA512[] = {
 427         0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03
 428 };
 429
 430 static const unsigned char *HASH_OID[] = {
 431         HASH_OID_SHA1,
 432         HASH_OID_SHA224,
 433         HASH_OID_SHA256,
 434         HASH_OID_SHA384,
 435         HASH_OID_SHA512
 436 };
 437
 438 static const br_hash_class *
 439 get_hash_impl(int hash_id)
 440 {
 441         size_t u;
 442
 443         for (u = 0; hash_functions[u].name; u ++) {
 444                 const br_hash_class *hc;
 445                 int id;
 446
 447                 hc = hash_functions[u].hclass;
 448                 id = (hc->desc >> BR_HASHDESC_ID_OFF) & BR_HASHDESC_ID_MASK;
 449                 if (id == hash_id) {
 450                         return hc;
 451                 }
 452         }
 453         return NULL;
 454 }
 455
 456 static size_t
 457 sp_do_sign(const br_ssl_server_policy_class **pctx,
 458         int hash_id, size_t hv_len, unsigned char *data, size_t len)
 459 {
 460         policy_context *pc;
 461         unsigned char hv[64];
 462
 463         pc = (policy_context *)pctx;
 464         memcpy(hv, data, hv_len);
 465         switch (pc->sk->key_type) {
 466                 size_t sig_len;
 467                 uint32_t x;
 468                 const unsigned char *hash_oid;
 469                 const br_hash_class *hc;
 470
 471         case BR_KEYTYPE_RSA:
 472                 if (hash_id == 0) {
 473                         hash_oid = NULL;
 474                 } else if (hash_id >= 2 && hash_id <= 6) {
 475                         hash_oid = HASH_OID[hash_id - 2];
 476                 } else {
 477                         if (pc->verbose) {
 478                                 fprintf(stderr, "ERROR: cannot RSA-sign with"
 479                                         " unknown hash function: %d\n",
 480                                         hash_id);
 481                         }
 482                         return 0;
 483                 }
 484                 sig_len = (pc->sk->key.rsa.n_bitlen + 7) >> 3;
 485                 if (len < sig_len) {
 486                         if (pc->verbose) {
 487                                 fprintf(stderr, "ERROR: cannot RSA-sign,"
 488                                         " buffer is too small"
 489                                         " (sig=%lu, buf=%lu)\n",
 490                                         (unsigned long)sig_len,
 491                                         (unsigned long)len);
 492                         }
 493                         return 0;
 494                 }
 495                 x = br_rsa_i31_pkcs1_sign(hash_oid, hv, hv_len,
 496                         &pc->sk->key.rsa, data);
 497                 if (!x) {
 498                         if (pc->verbose) {
 499                                 fprintf(stderr, "ERROR: RSA-sign failure\n");
 500                         }
 501                         return 0;
 502                 }
 503                 return sig_len;
 504
 505         case BR_KEYTYPE_EC:
 506                 hc = get_hash_impl(hash_id);
 507                 if (hc == NULL) {
 508                         if (pc->verbose) {
 509                                 fprintf(stderr, "ERROR: cannot RSA-sign with"
 510                                         " unknown hash function: %d\n",
 511                                         hash_id);
 512                         }
 513                         return 0;
 514                 }
 515                 if (len < 139) {
 516                         if (pc->verbose) {
 517                                 fprintf(stderr, "ERROR: cannot ECDSA-sign"
 518                                         " (output buffer = %lu)\n",
 519                                         (unsigned long)len);
 520                         }
 521                         return 0;
 522                 }
 523                 sig_len = br_ecdsa_i31_sign_asn1(&br_ec_prime_i31,
 524                         hc, hv, &pc->sk->key.ec, data);
 525                 if (sig_len == 0) {
 526                         if (pc->verbose) {
 527                                 fprintf(stderr, "ERROR: ECDSA-sign failure\n");
 528                         }
 529                         return 0;
 530                 }
 531                 return sig_len;
 532
 533         default:
 534                 return 0;
 535         }
 536 }
 537
 538 static const br_ssl_server_policy_class policy_vtable = {
 539         sizeof(policy_context),
 540         sp_choose,
 541         sp_do_keyx,
 542         sp_do_sign
 543 };
 544
 545 /* see brssl.h */
 546 int
 547 do_server(int argc, char *argv[])
 548 {
 549         int retcode;
 550         int verbose;
 551         int trace;
 552         int i, bidi;
 553         const char *bind_name;
 554         const char *port;
 555         unsigned vmin, vmax;
 556         cipher_suite *suites;
 557         size_t num_suites;
 558         uint16_t *suite_ids;
 559         unsigned hfuns;
 560         br_x509_certificate *chain;
 561         size_t chain_len;
 562         int cert_signer_algo;
 563         private_key *sk;
 564         size_t u;
 565         br_ssl_server_context cc;
 566         policy_context pc;
 567         br_ssl_session_cache_lru lru;
 568         unsigned char *iobuf, *cache;
 569         size_t iobuf_len, cache_len;
 570         uint32_t flags;
 571         int server_fd, fd;
 572
 573         retcode = 0;
 574         verbose = 1;
 575         trace = 0;
 576         bind_name = NULL;
 577         port = NULL;
 578         bidi = 1;
 579         vmin = 0;
 580         vmax = 0;
 581         suites = NULL;
 582         num_suites = 0;
 583         hfuns = 0;
 584         suite_ids = NULL;
 585         chain = NULL;
 586         chain_len = 0;
 587         sk = NULL;
 588         iobuf = NULL;
 589         iobuf_len = 0;
 590         cache = NULL;
 591         cache_len = (size_t)-1;
 592         flags = 0;
 593         server_fd = -1;
 594         fd = -1;
 595         for (i = 0; i < argc; i ++) {
 596                 const char *arg;
 597
 598                 arg = argv[i];
 599                 if (arg[0] != '-') {
 600                         usage_server();
 601                         goto server_exit_error;
 602                 }
 603                 if (eqstr(arg, "-v") || eqstr(arg, "-verbose")) {
 604                         verbose = 1;
 605                 } else if (eqstr(arg, "-q") || eqstr(arg, "-quiet")) {
 606                         verbose = 0;
 607                 } else if (eqstr(arg, "-trace")) {
 608                         trace = 1;
 609                 } else if (eqstr(arg, "-b")) {
 610                         if (++ i >= argc) {
 611                                 fprintf(stderr,
 612                                         "ERROR: no argument for '-b'\n");
 613                                 usage_server();
 614                                 goto server_exit_error;
 615                         }
 616                         if (bind_name != NULL) {
 617                                 fprintf(stderr, "ERROR: duplicate bind host\n");
 618                                 usage_server();
 619                                 goto server_exit_error;
 620                         }
 621                         bind_name = argv[i];
 622                 } else if (eqstr(arg, "-p")) {
 623                         if (++ i >= argc) {
 624                                 fprintf(stderr,
 625                                         "ERROR: no argument for '-p'\n");
 626                                 usage_server();
 627                                 goto server_exit_error;
 628                         }
 629                         if (port != NULL) {
 630                                 fprintf(stderr, "ERROR: duplicate bind port\n");
 631                                 usage_server();
 632                                 goto server_exit_error;
 633                         }
 634                         port = argv[i];
 635                 } else if (eqstr(arg, "-mono")) {
 636                         bidi = 0;
 637                 } else if (eqstr(arg, "-buf")) {
 638                         if (++ i >= argc) {
 639                                 fprintf(stderr,
 640                                         "ERROR: no argument for '-buf'\n");
 641                                 usage_server();
 642                                 goto server_exit_error;
 643                         }
 644                         arg = argv[i];
 645                         if (iobuf_len != 0) {
 646                                 fprintf(stderr,
 647                                         "ERROR: duplicate I/O buffer length\n");
 648                                 usage_server();
 649                                 goto server_exit_error;
 650                         }
 651                         iobuf_len = parse_size(arg);
 652                         if (iobuf_len == (size_t)-1) {
 653                                 usage_server();
 654                                 goto server_exit_error;
 655                         }
 656                 } else if (eqstr(arg, "-cache")) {
 657                         if (++ i >= argc) {
 658                                 fprintf(stderr,
 659                                         "ERROR: no argument for '-cache'\n");
 660                                 usage_server();
 661                                 goto server_exit_error;
 662                         }
 663                         arg = argv[i];
 664                         if (cache_len != (size_t)-1) {
 665                                 fprintf(stderr, "ERROR: duplicate session"
 666                                         " cache length\n");
 667                                 usage_server();
 668                                 goto server_exit_error;
 669                         }
 670                         cache_len = parse_size(arg);
 671                         if (cache_len == (size_t)-1) {
 672                                 usage_server();
 673                                 goto server_exit_error;
 674                         }
 675                 } else if (eqstr(arg, "-cert")) {
 676                         if (++ i >= argc) {
 677                                 fprintf(stderr,
 678                                         "ERROR: no argument for '-cert'\n");
 679                                 usage_server();
 680                                 goto server_exit_error;
 681                         }
 682                         if (chain != NULL) {
 683                                 fprintf(stderr,
 684                                         "ERROR: duplicate certificate chain\n");
 685                                 usage_server();
 686                                 goto server_exit_error;
 687                         }
 688                         arg = argv[i];
 689                         chain = read_certificates(arg, &chain_len);
 690                         if (chain == NULL || chain_len == 0) {
 691                                 goto server_exit_error;
 692                         }
 693                 } else if (eqstr(arg, "-key")) {
 694                         if (++ i >= argc) {
 695                                 fprintf(stderr,
 696                                         "ERROR: no argument for '-key'\n");
 697                                 usage_server();
 698                                 goto server_exit_error;
 699                         }
 700                         if (sk != NULL) {
 701                                 fprintf(stderr,
 702                                         "ERROR: duplicate private key\n");
 703                                 usage_server();
 704                                 goto server_exit_error;
 705                         }
 706                         arg = argv[i];
 707                         sk = read_private_key(arg);
 708                         if (sk == NULL) {
 709                                 goto server_exit_error;
 710                         }
 711                 } else if (eqstr(arg, "-list")) {
 712                         list_names();
 713                         goto server_exit;
 714                 } else if (eqstr(arg, "-vmin")) {
 715                         if (++ i >= argc) {
 716                                 fprintf(stderr,
 717                                         "ERROR: no argument for '-vmin'\n");
 718                                 usage_server();
 719                                 goto server_exit_error;
 720                         }
 721                         arg = argv[i];
 722                         if (vmin != 0) {
 723                                 fprintf(stderr,
 724                                         "ERROR: duplicate minimum version\n");
 725                                 usage_server();
 726                                 goto server_exit_error;
 727                         }
 728                         vmin = parse_version(arg, strlen(arg));
 729                         if (vmin == 0) {
 730                                 fprintf(stderr,
 731                                         "ERROR: unrecognised version '%s'\n",
 732                                         arg);
 733                                 usage_server();
 734                                 goto server_exit_error;
 735                         }
 736                 } else if (eqstr(arg, "-vmax")) {
 737                         if (++ i >= argc) {
 738                                 fprintf(stderr,
 739                                         "ERROR: no argument for '-vmax'\n");
 740                                 usage_server();
 741                                 goto server_exit_error;
 742                         }
 743                         arg = argv[i];
 744                         if (vmax != 0) {
 745                                 fprintf(stderr,
 746                                         "ERROR: duplicate maximum version\n");
 747                                 usage_server();
 748                                 goto server_exit_error;
 749                         }
 750                         vmax = parse_version(arg, strlen(arg));
 751                         if (vmax == 0) {
 752                                 fprintf(stderr,
 753                                         "ERROR: unrecognised version '%s'\n",
 754                                         arg);
 755                                 usage_server();
 756                                 goto server_exit_error;
 757                         }
 758                 } else if (eqstr(arg, "-cs")) {
 759                         if (++ i >= argc) {
 760                                 fprintf(stderr,
 761                                         "ERROR: no argument for '-cs'\n");
 762                                 usage_server();
 763                                 goto server_exit_error;
 764                         }
 765                         arg = argv[i];
 766                         if (suites != NULL) {
 767                                 fprintf(stderr, "ERROR: duplicate list"
 768                                         " of cipher suites\n");
 769                                 usage_server();
 770                                 goto server_exit_error;
 771                         }
 772                         suites = parse_suites(arg, &num_suites);
 773                         if (suites == NULL) {
 774                                 usage_server();
 775                                 goto server_exit_error;
 776                         }
 777                 } else if (eqstr(arg, "-hf")) {
 778                         unsigned x;
 779
 780                         if (++ i >= argc) {
 781                                 fprintf(stderr,
 782                                         "ERROR: no argument for '-hf'\n");
 783                                 usage_server();
 784                                 goto server_exit_error;
 785                         }
 786                         arg = argv[i];
 787                         x = parse_hash_functions(arg);
 788                         if (x == 0) {
 789                                 usage_server();
 790                                 goto server_exit_error;
 791                         }
 792                         hfuns |= x;
 793                 } else if (eqstr(arg, "-serverpref")) {
 794                         flags |= BR_OPT_ENFORCE_SERVER_PREFERENCES;
 795                 } else {
 796                         fprintf(stderr, "ERROR: unknown option: '%s'\n", arg);
 797                         usage_server();
 798                         goto server_exit_error;
 799                 }
 800         }
 801         if (port == NULL) {
 802                 port = "4433";
 803         }
 804         if (vmin == 0) {
 805                 vmin = BR_TLS10;
 806         }
 807         if (vmax == 0) {
 808                 vmax = BR_TLS12;
 809         }
 810         if (vmax < vmin) {
 811                 fprintf(stderr, "ERROR: impossible minimum/maximum protocol"
 812                         " version combination\n");
 813                 usage_server();
 814                 goto server_exit_error;
 815         }
 816         if (suites == NULL) {
 817                 num_suites = 0;
 818
 819                 for (u = 0; cipher_suites[u].name; u ++) {
 820                         if ((cipher_suites[u].req & REQ_TLS12) == 0
 821                                 || vmax >= BR_TLS12)
 822                         {
 823                                 num_suites ++;
 824                         }
 825                 }
 826                 suites = xmalloc(num_suites * sizeof *suites);
 827                 num_suites = 0;
 828                 for (u = 0; cipher_suites[u].name; u ++) {
 829                         if ((cipher_suites[u].req & REQ_TLS12) == 0
 830                                 || vmax >= BR_TLS12)
 831                         {
 832                                 suites[num_suites ++] = cipher_suites[u];
 833                         }
 834                 }
 835         }
 836         if (hfuns == 0) {
 837                 hfuns = (unsigned)-1;
 838         }
 839         if (chain == NULL || chain_len == 0) {
 840                 fprintf(stderr, "ERROR: no certificate chain provided\n");
 841                 goto server_exit_error;
 842         }
 843         if (sk == NULL) {
 844                 fprintf(stderr, "ERROR: no private key provided\n");
 845                 goto server_exit_error;
 846         }
 847         switch (sk->key_type) {
 848                 int curve;
 849                 uint32_t supp;
 850
 851         case BR_KEYTYPE_RSA:
 852                 break;
 853         case BR_KEYTYPE_EC:
 854                 curve = sk->key.ec.curve;
 855                 supp = br_ec_prime_i31.supported_curves;
 856                 if (curve > 31 || !((supp >> curve) & 1)) {
 857                         fprintf(stderr, "ERROR: private key curve (%d)"
 858                                 " is not supported\n", curve);
 859                         goto server_exit_error;
 860                 }
 861                 break;
 862         default:
 863                 fprintf(stderr, "ERROR: unsupported private key type (%d)\n",
 864                         sk->key_type);
 865                 break;
 866         }
 867         cert_signer_algo = get_cert_signer_algo(chain);
 868         if (cert_signer_algo < 0) {
 869                 fprintf(stderr, "ERROR: server certificate cannot be"
 870                         " decoded (err=%d)\n", -cert_signer_algo);
 871                 goto server_exit_error;
 872         } else if (verbose) {
 873                 const char *csas;
 874
 875                 switch (cert_signer_algo) {
 876                 case BR_KEYTYPE_RSA: csas = "RSA"; break;
 877                 case BR_KEYTYPE_EC:  csas = "EC"; break;
 878                 default:
 879                         csas = "unknown";
 880                         break;
 881                 }
 882                 fprintf(stderr, "Issuing CA key type: %d (%s)\n",
 883                         cert_signer_algo, csas);
 884         }
 885         if (iobuf_len == 0) {
 886                 if (bidi) {
 887                         iobuf_len = BR_SSL_BUFSIZE_BIDI;
 888                 } else {
 889                         iobuf_len = BR_SSL_BUFSIZE_MONO;
 890                 }
 891         }
 892         iobuf = xmalloc(iobuf_len);
 893         if (cache_len == (size_t)-1) {
 894                 cache_len = 5000;
 895         }
 896         cache = xmalloc(cache_len);
 897
 898         /*
 899          * Compute implementation requirements and inject implementations.
 900          */
 901         suite_ids = xmalloc(num_suites * sizeof *suite_ids);
 902         br_ssl_server_zero(&cc);
 903         br_ssl_engine_set_versions(&cc.eng, vmin, vmax);
 904         br_ssl_server_set_all_flags(&cc, flags);
 905         if (vmin <= BR_TLS11) {
 906                 if (!(hfuns & (1 << br_md5_ID))) {
 907                         fprintf(stderr, "ERROR: TLS 1.0 and 1.1 need MD5\n");
 908                         goto server_exit_error;
 909                 }
 910                 if (!(hfuns & (1 << br_sha1_ID))) {
 911                         fprintf(stderr, "ERROR: TLS 1.0 and 1.1 need SHA-1\n");
 912                         goto server_exit_error;
 913                 }
 914         }
 915         for (u = 0; u < num_suites; u ++) {
 916                 unsigned req;
 917
 918                 req = suites[u].req;
 919                 suite_ids[u] = suites[u].suite;
 920                 if ((req & REQ_TLS12) != 0 && vmax < BR_TLS12) {
 921                         fprintf(stderr,
 922                                 "ERROR: cipher suite %s requires TLS 1.2\n",
 923                                 suites[u].name);
 924                         goto server_exit_error;
 925                 }
 926                 if ((req & REQ_SHA1) != 0 && !(hfuns & (1 << br_sha1_ID))) {
 927                         fprintf(stderr,
 928                                 "ERROR: cipher suite %s requires SHA-1\n",
 929                                 suites[u].name);
 930                         goto server_exit_error;
 931                 }
 932                 if ((req & REQ_SHA256) != 0 && !(hfuns & (1 << br_sha256_ID))) {
 933                         fprintf(stderr,
 934                                 "ERROR: cipher suite %s requires SHA-256\n",
 935                                 suites[u].name);
 936                         goto server_exit_error;
 937                 }
 938                 if ((req & REQ_SHA384) != 0 && !(hfuns & (1 << br_sha384_ID))) {
 939                         fprintf(stderr,
 940                                 "ERROR: cipher suite %s requires SHA-384\n",
 941                                 suites[u].name);
 942                         goto server_exit_error;
 943                 }
 944                 /* TODO: algorithm implementation selection */
 945                 if ((req & REQ_AESCBC) != 0) {
 946                         br_ssl_engine_set_aes_cbc(&cc.eng,
 947                                 &br_aes_ct_cbcenc_vtable,
 948                                 &br_aes_ct_cbcdec_vtable);
 949                         br_ssl_engine_set_cbc(&cc.eng,
 950                                 &br_sslrec_in_cbc_vtable,
 951                                 &br_sslrec_out_cbc_vtable);
 952                 }
 953                 if ((req & REQ_AESGCM) != 0) {
 954                         br_ssl_engine_set_aes_ctr(&cc.eng,
 955                                 &br_aes_ct_ctr_vtable);
 956                         br_ssl_engine_set_ghash(&cc.eng,
 957                                 &br_ghash_ctmul);
 958                         br_ssl_engine_set_gcm(&cc.eng,
 959                                 &br_sslrec_in_gcm_vtable,
 960                                 &br_sslrec_out_gcm_vtable);
 961                 }
 962                 if ((req & REQ_3DESCBC) != 0) {
 963                         br_ssl_engine_set_des_cbc(&cc.eng,
 964                                 &br_des_ct_cbcenc_vtable,
 965                                 &br_des_ct_cbcdec_vtable);
 966                         br_ssl_engine_set_cbc(&cc.eng,
 967                                 &br_sslrec_in_cbc_vtable,
 968                                 &br_sslrec_out_cbc_vtable);
 969                 }
 970                 if ((req & (REQ_ECDHE_RSA | REQ_ECDHE_ECDSA)) != 0) {
 971                         br_ssl_engine_set_ec(&cc.eng, &br_ec_prime_i31);
 972                 }
 973         }
 974         br_ssl_engine_set_suites(&cc.eng, suite_ids, num_suites);
 975
 976         for (u = 0; hash_functions[u].name; u ++) {
 977                 const br_hash_class *hc;
 978                 int id;
 979
 980                 hc = hash_functions[u].hclass;
 981                 id = (hc->desc >> BR_HASHDESC_ID_OFF) & BR_HASHDESC_ID_MASK;
 982                 if ((hfuns & ((unsigned)1 << id)) != 0) {
 983                         br_ssl_engine_set_hash(&cc.eng, id, hc);
 984                 }
 985         }
 986         if (vmin <= BR_TLS11) {
 987                 br_ssl_engine_set_prf10(&cc.eng, &br_tls10_prf);
 988         }
 989         if (vmax >= BR_TLS12) {
 990                 if ((hfuns & ((unsigned)1 << br_sha256_ID)) != 0) {
 991                         br_ssl_engine_set_prf_sha256(&cc.eng,
 992                                 &br_tls12_sha256_prf);
 993                 }
 994                 if ((hfuns & ((unsigned)1 << br_sha384_ID)) != 0) {
 995                         br_ssl_engine_set_prf_sha384(&cc.eng,
 996                                 &br_tls12_sha384_prf);
 997                 }
 998         }
 999
1000         br_ssl_session_cache_lru_init(&lru, cache, cache_len);
1001         br_ssl_server_set_cache(&cc, &lru.vtable);
1002
1003         pc.vtable = &policy_vtable;
1004         pc.verbose = verbose;
1005         pc.chain = chain;
1006         pc.chain_len = chain_len;
1007         pc.cert_signer_algo = cert_signer_algo;
1008         pc.sk = sk;
1009         br_ssl_server_set_policy(&cc, &pc.vtable);
1010
1011         br_ssl_engine_set_buffer(&cc.eng, iobuf, iobuf_len, bidi);
1012
1013         /*
1014          * Open the server socket.
1015          */
1016         server_fd = host_bind(bind_name, port, verbose);
1017         if (server_fd < 0) {
1018                 goto server_exit_error;
1019         }
1020
1021         /*
1022          * Process incoming clients, one at a time. Note that we do not
1023          * accept any client until the previous connection has finished:
1024          * this is voluntary, since the tool uses stdin/stdout for
1025          * application data, and thus cannot really run two connections
1026          * simultaneously.
1027          */
1028         for (;;) {
1029                 int x;
1030
1031                 fd = accept_client(server_fd, verbose);
1032                 if (fd < 0) {
1033                         goto server_exit_error;
1034                 }
1035                 br_ssl_server_reset(&cc);
1036                 x = run_ssl_engine(&cc.eng, fd,
1037                         (verbose ? RUN_ENGINE_VERBOSE : 0)
1038                         | (trace ? RUN_ENGINE_TRACE : 0));
1039                 close(fd);
1040                 fd = -1;
1041                 if (x < -1) {
1042                         goto server_exit_error;
1043                 }
1044         }
1045
1046         /*
1047          * Release allocated structures.
1048          */
1049 server_exit:
1050         xfree(suites);
1051         xfree(suite_ids);
1052         if (chain != NULL) {
1053                 for (u = 0; u < chain_len; u ++) {
1054                         xfree(chain[u].data);
1055                 }
1056                 xfree(chain);
1057         }
1058         free_private_key(sk);
1059         xfree(iobuf);
1060         xfree(cache);
1061         if (fd >= 0) {
1062                 close(fd);
1063         }
1064         return retcode;
1065
1066 server_exit_error:
1067         retcode = -1;
1068         goto server_exit;
1069 }