_ 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 #include <signal.h>
  31
  32 #ifdef _WIN32
  33 #include <winsock2.h>
  34 #include <ws2tcpip.h>
  35 #else
  36 #include <sys/types.h>
  37 #include <sys/socket.h>
  38 #include <netdb.h>
  39 #include <netinet/in.h>
  40 #include <arpa/inet.h>
  41 #include <unistd.h>
  42 #include <fcntl.h>
  43
  44 #define SOCKET             int
  45 #define INVALID_SOCKET     (-1)
  46 #define SOCKADDR_STORAGE   struct sockaddr_storage
  47 #endif
  48
  49 #include "brssl.h"
  50
  51 static SOCKET
  52 host_bind(const char *host, const char *port, int verbose)
  53 {
  54         struct addrinfo hints, *si, *p;
  55         SOCKET fd;
  56         int err;
  57
  58         memset(&hints, 0, sizeof hints);
  59         hints.ai_family = PF_UNSPEC;
  60         hints.ai_socktype = SOCK_STREAM;
  61         err = getaddrinfo(host, port, &hints, &si);
  62         if (err != 0) {
  63                 fprintf(stderr, "ERROR: getaddrinfo(): %s\n",
  64                         gai_strerror(err));
  65                 return INVALID_SOCKET;
  66         }
  67         fd = INVALID_SOCKET;
  68         for (p = si; p != NULL; p = p->ai_next) {
  69                 struct sockaddr *sa;
  70                 struct sockaddr_in sa4;
  71                 struct sockaddr_in6 sa6;
  72                 size_t sa_len;
  73                 void *addr;
  74                 int opt;
  75
  76                 sa = (struct sockaddr *)p->ai_addr;
  77                 if (sa->sa_family == AF_INET) {
  78                         sa4 = *(struct sockaddr_in *)sa;
  79                         sa = (struct sockaddr *)&sa4;
  80                         sa_len = sizeof sa4;
  81                         addr = &sa4.sin_addr;
  82                         if (host == NULL) {
  83                                 sa4.sin_addr.s_addr = INADDR_ANY;
  84                         }
  85                 } else if (sa->sa_family == AF_INET6) {
  86                         sa6 = *(struct sockaddr_in6 *)sa;
  87                         sa = (struct sockaddr *)&sa6;
  88                         sa_len = sizeof sa6;
  89                         addr = &sa6.sin6_addr;
  90                         if (host == NULL) {
  91                                 sa6.sin6_addr = in6addr_any;
  92                         }
  93                 } else {
  94                         addr = NULL;
  95                         sa_len = p->ai_addrlen;
  96                 }
  97                 if (verbose) {
  98                         char tmp[INET6_ADDRSTRLEN + 50];
  99
 100                         if (addr != NULL) {
 101                                 if (!inet_ntop(p->ai_family, addr,
 102                                         tmp, sizeof tmp))
 103                                 {
 104                                         strcpy(tmp, "<invalid>");
 105                                 }
 106                         } else {
 107                                 sprintf(tmp, "<unknown family: %d>",
 108                                         (int)sa->sa_family);
 109                         }
 110                         fprintf(stderr, "binding to: %s\n", tmp);
 111                 }
 112                 fd = socket(p->ai_family, p->ai_socktype, p->ai_protocol);
 113                 if (fd == INVALID_SOCKET) {
 114                         if (verbose) {
 115                                 perror("socket()");
 116                         }
 117                         continue;
 118                 }
 119                 opt = 1;
 120                 setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
 121                         (void *)&opt, sizeof opt);
 122                 opt = 0;
 123                 setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY,
 124                         (void *)&opt, sizeof opt);
 125                 if (bind(fd, sa, sa_len) < 0) {
 126                         if (verbose) {
 127                                 perror("bind()");
 128                         }
 129 #ifdef _WIN32
 130                         closesocket(fd);
 131 #else
 132                         close(fd);
 133 #endif
 134                         continue;
 135                 }
 136                 break;
 137         }
 138         if (p == NULL) {
 139                 freeaddrinfo(si);
 140                 fprintf(stderr, "ERROR: failed to bind\n");
 141                 return INVALID_SOCKET;
 142         }
 143         freeaddrinfo(si);
 144         if (listen(fd, 5) < 0) {
 145                 if (verbose) {
 146                         perror("listen()");
 147                 }
 148 #ifdef _WIN32
 149                 closesocket(fd);
 150 #else
 151                 close(fd);
 152 #endif
 153                 return INVALID_SOCKET;
 154         }
 155         if (verbose) {
 156                 fprintf(stderr, "bound.\n");
 157         }
 158         return fd;
 159 }
 160
 161 static SOCKET
 162 accept_client(SOCKET server_fd, int verbose)
 163 {
 164         int fd;
 165         SOCKADDR_STORAGE sa;
 166         socklen_t sa_len;
 167
 168         sa_len = sizeof sa;
 169         fd = accept(server_fd, (struct sockaddr *)&sa, &sa_len);
 170         if (fd == INVALID_SOCKET) {
 171                 if (verbose) {
 172                         perror("accept()");
 173                 }
 174                 return INVALID_SOCKET;
 175         }
 176         if (verbose) {
 177                 char tmp[INET6_ADDRSTRLEN + 50];
 178                 const char *name;
 179
 180                 name = NULL;
 181                 switch (((struct sockaddr *)&sa)->sa_family) {
 182                 case AF_INET:
 183                         name = inet_ntop(AF_INET,
 184                                 &((struct sockaddr_in *)&sa)->sin_addr,
 185                                 tmp, sizeof tmp);
 186                         break;
 187                 case AF_INET6:
 188                         name = inet_ntop(AF_INET6,
 189                                 &((struct sockaddr_in6 *)&sa)->sin6_addr,
 190                                 tmp, sizeof tmp);
 191                         break;
 192                 }
 193                 if (name == NULL) {
 194                         sprintf(tmp, "<unknown: %lu>", (unsigned long)
 195                                 ((struct sockaddr *)&sa)->sa_family);
 196                         name = tmp;
 197                 }
 198                 fprintf(stderr, "accepting connection from: %s\n", name);
 199         }
 200
 201         /*
 202          * We make the socket non-blocking, since we are going to use
 203          * poll() or select() to organise I/O.
 204          */
 205 #ifdef _WIN32
 206         {
 207                 u_long arg;
 208
 209                 arg = 1;
 210                 ioctlsocket(fd, FIONBIO, &arg);
 211         }
 212 #else
 213         fcntl(fd, F_SETFL, O_NONBLOCK);
 214 #endif
 215         return fd;
 216 }
 217
 218 static void
 219 usage_server(void)
 220 {
 221         fprintf(stderr,
 222 "usage: brssl server [ options ]\n");
 223         fprintf(stderr,
 224 "options:\n");
 225         fprintf(stderr,
 226 "   -q              suppress verbose messages\n");
 227         fprintf(stderr,
 228 "   -trace          activate extra debug messages (dump of all packets)\n");
 229         fprintf(stderr,
 230 "   -b name         bind to a specific address or host name\n");
 231         fprintf(stderr,
 232 "   -p port         bind to a specific port (default: 4433)\n");
 233         fprintf(stderr,
 234 "   -mono           use monodirectional buffering\n");
 235         fprintf(stderr,
 236 "   -buf length     set the I/O buffer length (in bytes)\n");
 237         fprintf(stderr,
 238 "   -cache length   set the session cache storage length (in bytes)\n");
 239         fprintf(stderr,
 240 "   -cert fname     read certificate chain from file 'fname'\n");
 241         fprintf(stderr,
 242 "   -key fname      read private key from file 'fname'\n");
 243         fprintf(stderr,
 244 "   -CA file        add trust anchors from 'file' (for client auth)\n");
 245         fprintf(stderr,
 246 "   -anon_ok        request but do not require a client certificate\n");
 247         fprintf(stderr,
 248 "   -list           list supported names (protocols, algorithms...)\n");
 249         fprintf(stderr,
 250 "   -vmin name      set minimum supported version (default: TLS-1.0)\n");
 251         fprintf(stderr,
 252 "   -vmax name      set maximum supported version (default: TLS-1.2)\n");
 253         fprintf(stderr,
 254 "   -cs names       set list of supported cipher suites (comma-separated)\n");
 255         fprintf(stderr,
 256 "   -hf names       add support for some hash functions (comma-separated)\n");
 257         fprintf(stderr,
 258 "   -cbhash         test hashing in policy callback\n");
 259         fprintf(stderr,
 260 "   -serverpref     enforce server's preferences for cipher suites\n");
 261         fprintf(stderr,
 262 "   -noreneg        prohibit renegotiations\n");
 263         fprintf(stderr,
 264 "   -alpn name      add protocol name to list of protocols (ALPN extension)\n");
 265         fprintf(stderr,
 266 "   -strictalpn     fail on ALPN mismatch\n");
 267         exit(EXIT_FAILURE);
 268 }
 269
 270 typedef struct {
 271         const br_ssl_server_policy_class *vtable;
 272         int verbose;
 273         br_x509_certificate *chain;
 274         size_t chain_len;
 275         int cert_signer_algo;
 276         private_key *sk;
 277         int cbhash;
 278 } policy_context;
 279
 280 static void
 281 print_hashes(unsigned chashes)
 282 {
 283         int i;
 284
 285         for (i = 2; i <= 6; i ++) {
 286                 if ((chashes >> i) & 1) {
 287                         int z;
 288
 289                         switch (i) {
 290                         case 3: z = 224; break;
 291                         case 4: z = 256; break;
 292                         case 5: z = 384; break;
 293                         case 6: z = 512; break;
 294                         default:
 295                                 z = 1;
 296                                 break;
 297                         }
 298                         fprintf(stderr, " sha%d", z);
 299                 }
 300         }
 301 }
 302
 303 static unsigned
 304 choose_hash(unsigned chashes)
 305 {
 306         unsigned hash_id;
 307
 308         for (hash_id = 6; hash_id >= 2; hash_id --) {
 309                 if (((chashes >> hash_id) & 1) != 0) {
 310                         return hash_id;
 311                 }
 312         }
 313         /*
 314          * Normally unreachable.
 315          */
 316         return 0;
 317 }
 318
 319 static int
 320 sp_choose(const br_ssl_server_policy_class **pctx,
 321         const br_ssl_server_context *cc,
 322         br_ssl_server_choices *choices)
 323 {
 324         policy_context *pc;
 325         const br_suite_translated *st;
 326         size_t u, st_num;
 327         unsigned chashes;
 328
 329         pc = (policy_context *)pctx;
 330         st = br_ssl_server_get_client_suites(cc, &st_num);
 331         chashes = br_ssl_server_get_client_hashes(cc);
 332         if (pc->verbose) {
 333                 fprintf(stderr, "Client parameters:\n");
 334                 fprintf(stderr, "   Maximum version:      ");
 335                 switch (cc->client_max_version) {
 336                 case BR_SSL30:
 337                         fprintf(stderr, "SSL 3.0");
 338                         break;
 339                 case BR_TLS10:
 340                         fprintf(stderr, "TLS 1.0");
 341                         break;
 342                 case BR_TLS11:
 343                         fprintf(stderr, "TLS 1.1");
 344                         break;
 345                 case BR_TLS12:
 346                         fprintf(stderr, "TLS 1.2");
 347                         break;
 348                 default:
 349                         fprintf(stderr, "unknown (0x%04X)",
 350                                 (unsigned)cc->client_max_version);
 351                         break;
 352                 }
 353                 fprintf(stderr, "\n");
 354                 fprintf(stderr, "   Compatible cipher suites:\n");
 355                 for (u = 0; u < st_num; u ++) {
 356                         char csn[80];
 357
 358                         get_suite_name_ext(st[u][0], csn, sizeof csn);
 359                         fprintf(stderr, "      %s\n", csn);
 360                 }
 361                 fprintf(stderr, "   Common sign+hash functions:\n");
 362                 if ((chashes & 0xFF) != 0) {
 363                         fprintf(stderr, "      with RSA:");
 364                         print_hashes(chashes);
 365                         fprintf(stderr, "\n");
 366                 }
 367                 if ((chashes >> 8) != 0) {
 368                         fprintf(stderr, "      with ECDSA:");
 369                         print_hashes(chashes >> 8);
 370                         fprintf(stderr, "\n");
 371                 }
 372         }
 373         for (u = 0; u < st_num; u ++) {
 374                 unsigned tt;
 375
 376                 tt = st[u][1];
 377                 switch (tt >> 12) {
 378                 case BR_SSLKEYX_RSA:
 379                         if (pc->sk->key_type == BR_KEYTYPE_RSA) {
 380                                 choices->cipher_suite = st[u][0];
 381                                 goto choose_ok;
 382                         }
 383                         break;
 384                 case BR_SSLKEYX_ECDHE_RSA:
 385                         if (pc->sk->key_type == BR_KEYTYPE_RSA) {
 386                                 choices->cipher_suite = st[u][0];
 387                                 if (br_ssl_engine_get_version(&cc->eng)
 388                                         < BR_TLS12)
 389                                 {
 390                                         if (pc->cbhash) {
 391                                                 choices->algo_id = 0x0001;
 392                                         } else {
 393                                                 choices->algo_id = 0xFF00;
 394                                         }
 395                                 } else {
 396                                         unsigned id;
 397
 398                                         id = choose_hash(chashes);
 399                                         if (pc->cbhash) {
 400                                                 choices->algo_id =
 401                                                         (id << 8) + 0x01;
 402                                         } else {
 403                                                 choices->algo_id = 0xFF00 + id;
 404                                         }
 405                                 }
 406                                 goto choose_ok;
 407                         }
 408                         break;
 409                 case BR_SSLKEYX_ECDHE_ECDSA:
 410                         if (pc->sk->key_type == BR_KEYTYPE_EC) {
 411                                 choices->cipher_suite = st[u][0];
 412                                 if (br_ssl_engine_get_version(&cc->eng)
 413                                         < BR_TLS12)
 414                                 {
 415                                         if (pc->cbhash) {
 416                                                 choices->algo_id = 0x0203;
 417                                         } else {
 418                                                 choices->algo_id =
 419                                                         0xFF00 + br_sha1_ID;
 420                                         }
 421                                 } else {
 422                                         unsigned id;
 423
 424                                         id = choose_hash(chashes >> 8);
 425                                         if (pc->cbhash) {
 426                                                 choices->algo_id =
 427                                                         (id << 8) + 0x03;
 428                                         } else {
 429                                                 choices->algo_id =
 430                                                         0xFF00 + id;
 431                                         }
 432                                 }
 433                                 goto choose_ok;
 434                         }
 435                         break;
 436                 case BR_SSLKEYX_ECDH_RSA:
 437                         if (pc->sk->key_type == BR_KEYTYPE_EC
 438                                 && pc->cert_signer_algo == BR_KEYTYPE_RSA)
 439                         {
 440                                 choices->cipher_suite = st[u][0];
 441                                 goto choose_ok;
 442                         }
 443                         break;
 444                 case BR_SSLKEYX_ECDH_ECDSA:
 445                         if (pc->sk->key_type == BR_KEYTYPE_EC
 446                                 && pc->cert_signer_algo == BR_KEYTYPE_EC)
 447                         {
 448                                 choices->cipher_suite = st[u][0];
 449                                 goto choose_ok;
 450                         }
 451                         break;
 452                 }
 453         }
 454         return 0;
 455
 456 choose_ok:
 457         choices->chain = pc->chain;
 458         choices->chain_len = pc->chain_len;
 459         if (pc->verbose) {
 460                 char csn[80];
 461
 462                 get_suite_name_ext(choices->cipher_suite, csn, sizeof csn);
 463                 fprintf(stderr, "Using: %s\n", csn);
 464         }
 465         return 1;
 466 }
 467
 468 static uint32_t
 469 sp_do_keyx(const br_ssl_server_policy_class **pctx,
 470         unsigned char *data, size_t *len)
 471 {
 472         policy_context *pc;
 473         uint32_t r;
 474         size_t xoff, xlen;
 475
 476         pc = (policy_context *)pctx;
 477         switch (pc->sk->key_type) {
 478                 const br_ec_impl *iec;
 479
 480         case BR_KEYTYPE_RSA:
 481                 return br_rsa_ssl_decrypt(
 482                         br_rsa_private_get_default(),
 483                         &pc->sk->key.rsa, data, *len);
 484         case BR_KEYTYPE_EC:
 485                 iec = br_ec_get_default();
 486                 r = iec->mul(data, *len, pc->sk->key.ec.x,
 487                         pc->sk->key.ec.xlen, pc->sk->key.ec.curve);
 488                 xoff = iec->xoff(pc->sk->key.ec.curve, &xlen);
 489                 memmove(data, data + xoff, xlen);
 490                 *len = xlen;
 491                 return r;
 492         default:
 493                 fprintf(stderr, "ERROR: unknown private key type (%d)\n",
 494                         (int)pc->sk->key_type);
 495                 return 0;
 496         }
 497 }
 498
 499 static size_t
 500 sp_do_sign(const br_ssl_server_policy_class **pctx,
 501         unsigned algo_id, unsigned char *data, size_t hv_len, size_t len)
 502 {
 503         policy_context *pc;
 504         unsigned char hv[64];
 505
 506         pc = (policy_context *)pctx;
 507         if (algo_id >= 0xFF00) {
 508                 algo_id &= 0xFF;
 509                 memcpy(hv, data, hv_len);
 510         } else {
 511                 const br_hash_class *hc;
 512                 br_hash_compat_context zc;
 513
 514                 if (pc->verbose) {
 515                         fprintf(stderr, "Callback hashing, algo = 0x%04X,"
 516                                 " data_len = %lu\n",
 517                                 algo_id, (unsigned long)hv_len);
 518                 }
 519                 algo_id >>= 8;
 520                 hc = get_hash_impl(algo_id);
 521                 if (hc == NULL) {
 522                         if (pc->verbose) {
 523                                 fprintf(stderr,
 524                                         "ERROR: unsupported hash function %u\n",
 525                                         algo_id);
 526                         }
 527                         return 0;
 528                 }
 529                 hc->init(&zc.vtable);
 530                 hc->update(&zc.vtable, data, hv_len);
 531                 hc->out(&zc.vtable, hv);
 532                 hv_len = (hc->desc >> BR_HASHDESC_OUT_OFF)
 533                         & BR_HASHDESC_OUT_MASK;
 534         }
 535         switch (pc->sk->key_type) {
 536                 size_t sig_len;
 537                 uint32_t x;
 538                 const unsigned char *hash_oid;
 539                 const br_hash_class *hc;
 540
 541         case BR_KEYTYPE_RSA:
 542                 hash_oid = get_hash_oid(algo_id);
 543                 if (hash_oid == NULL && algo_id != 0) {
 544                         if (pc->verbose) {
 545                                 fprintf(stderr, "ERROR: cannot RSA-sign with"
 546                                         " unknown hash function: %u\n",
 547                                         algo_id);
 548                         }
 549                         return 0;
 550                 }
 551                 sig_len = (pc->sk->key.rsa.n_bitlen + 7) >> 3;
 552                 if (len < sig_len) {
 553                         if (pc->verbose) {
 554                                 fprintf(stderr, "ERROR: cannot RSA-sign,"
 555                                         " buffer is too small"
 556                                         " (sig=%lu, buf=%lu)\n",
 557                                         (unsigned long)sig_len,
 558                                         (unsigned long)len);
 559                         }
 560                         return 0;
 561                 }
 562                 x = br_rsa_pkcs1_sign_get_default()(
 563                         hash_oid, hv, hv_len, &pc->sk->key.rsa, data);
 564                 if (!x) {
 565                         if (pc->verbose) {
 566                                 fprintf(stderr, "ERROR: RSA-sign failure\n");
 567                         }
 568                         return 0;
 569                 }
 570                 return sig_len;
 571
 572         case BR_KEYTYPE_EC:
 573                 hc = get_hash_impl(algo_id);
 574                 if (hc == NULL) {
 575                         if (pc->verbose) {
 576                                 fprintf(stderr, "ERROR: cannot ECDSA-sign with"
 577                                         " unknown hash function: %u\n",
 578                                         algo_id);
 579                         }
 580                         return 0;
 581                 }
 582                 if (len < 139) {
 583                         if (pc->verbose) {
 584                                 fprintf(stderr, "ERROR: cannot ECDSA-sign"
 585                                         " (output buffer = %lu)\n",
 586                                         (unsigned long)len);
 587                         }
 588                         return 0;
 589                 }
 590                 sig_len = br_ecdsa_sign_asn1_get_default()(
 591                         br_ec_get_default(), hc, hv, &pc->sk->key.ec, data);
 592                 if (sig_len == 0) {
 593                         if (pc->verbose) {
 594                                 fprintf(stderr, "ERROR: ECDSA-sign failure\n");
 595                         }
 596                         return 0;
 597                 }
 598                 return sig_len;
 599
 600         default:
 601                 return 0;
 602         }
 603 }
 604
 605 static const br_ssl_server_policy_class policy_vtable = {
 606         sizeof(policy_context),
 607         sp_choose,
 608         sp_do_keyx,
 609         sp_do_sign
 610 };
 611
 612 void
 613 free_alpn(void *alpn)
 614 {
 615         xfree(*(char **)alpn);
 616 }
 617
 618 /* see brssl.h */
 619 int
 620 do_server(int argc, char *argv[])
 621 {
 622         int retcode;
 623         int verbose;
 624         int trace;
 625         int i, bidi;
 626         const char *bind_name;
 627         const char *port;
 628         unsigned vmin, vmax;
 629         cipher_suite *suites;
 630         size_t num_suites;
 631         uint16_t *suite_ids;
 632         unsigned hfuns;
 633         int cbhash;
 634         br_x509_certificate *chain;
 635         size_t chain_len;
 636         int cert_signer_algo;
 637         private_key *sk;
 638         anchor_list anchors = VEC_INIT;
 639         VECTOR(char *) alpn_names = VEC_INIT;
 640         br_x509_minimal_context xc;
 641         const br_hash_class *dnhash;
 642         size_t u;
 643         br_ssl_server_context cc;
 644         policy_context pc;
 645         br_ssl_session_cache_lru lru;
 646         unsigned char *iobuf, *cache;
 647         size_t iobuf_len, cache_len;
 648         uint32_t flags;
 649         SOCKET server_fd, fd;
 650
 651         retcode = 0;
 652         verbose = 1;
 653         trace = 0;
 654         bind_name = NULL;
 655         port = NULL;
 656         bidi = 1;
 657         vmin = 0;
 658         vmax = 0;
 659         suites = NULL;
 660         num_suites = 0;
 661         hfuns = 0;
 662         cbhash = 0;
 663         suite_ids = NULL;
 664         chain = NULL;
 665         chain_len = 0;
 666         sk = NULL;
 667         iobuf = NULL;
 668         iobuf_len = 0;
 669         cache = NULL;
 670         cache_len = (size_t)-1;
 671         flags = 0;
 672         server_fd = INVALID_SOCKET;
 673         fd = INVALID_SOCKET;
 674         for (i = 0; i < argc; i ++) {
 675                 const char *arg;
 676
 677                 arg = argv[i];
 678                 if (arg[0] != '-') {
 679                         usage_server();
 680                         goto server_exit_error;
 681                 }
 682                 if (eqstr(arg, "-v") || eqstr(arg, "-verbose")) {
 683                         verbose = 1;
 684                 } else if (eqstr(arg, "-q") || eqstr(arg, "-quiet")) {
 685                         verbose = 0;
 686                 } else if (eqstr(arg, "-trace")) {
 687                         trace = 1;
 688                 } else if (eqstr(arg, "-b")) {
 689                         if (++ i >= argc) {
 690                                 fprintf(stderr,
 691                                         "ERROR: no argument for '-b'\n");
 692                                 usage_server();
 693                                 goto server_exit_error;
 694                         }
 695                         if (bind_name != NULL) {
 696                                 fprintf(stderr, "ERROR: duplicate bind host\n");
 697                                 usage_server();
 698                                 goto server_exit_error;
 699                         }
 700                         bind_name = argv[i];
 701                 } else if (eqstr(arg, "-p")) {
 702                         if (++ i >= argc) {
 703                                 fprintf(stderr,
 704                                         "ERROR: no argument for '-p'\n");
 705                                 usage_server();
 706                                 goto server_exit_error;
 707                         }
 708                         if (port != NULL) {
 709                                 fprintf(stderr, "ERROR: duplicate bind port\n");
 710                                 usage_server();
 711                                 goto server_exit_error;
 712                         }
 713                         port = argv[i];
 714                 } else if (eqstr(arg, "-mono")) {
 715                         bidi = 0;
 716                 } else if (eqstr(arg, "-buf")) {
 717                         if (++ i >= argc) {
 718                                 fprintf(stderr,
 719                                         "ERROR: no argument for '-buf'\n");
 720                                 usage_server();
 721                                 goto server_exit_error;
 722                         }
 723                         arg = argv[i];
 724                         if (iobuf_len != 0) {
 725                                 fprintf(stderr,
 726                                         "ERROR: duplicate I/O buffer length\n");
 727                                 usage_server();
 728                                 goto server_exit_error;
 729                         }
 730                         iobuf_len = parse_size(arg);
 731                         if (iobuf_len == (size_t)-1) {
 732                                 usage_server();
 733                                 goto server_exit_error;
 734                         }
 735                 } else if (eqstr(arg, "-cache")) {
 736                         if (++ i >= argc) {
 737                                 fprintf(stderr,
 738                                         "ERROR: no argument for '-cache'\n");
 739                                 usage_server();
 740                                 goto server_exit_error;
 741                         }
 742                         arg = argv[i];
 743                         if (cache_len != (size_t)-1) {
 744                                 fprintf(stderr, "ERROR: duplicate session"
 745                                         " cache length\n");
 746                                 usage_server();
 747                                 goto server_exit_error;
 748                         }
 749                         cache_len = parse_size(arg);
 750                         if (cache_len == (size_t)-1) {
 751                                 usage_server();
 752                                 goto server_exit_error;
 753                         }
 754                 } else if (eqstr(arg, "-cert")) {
 755                         if (++ i >= argc) {
 756                                 fprintf(stderr,
 757                                         "ERROR: no argument for '-cert'\n");
 758                                 usage_server();
 759                                 goto server_exit_error;
 760                         }
 761                         if (chain != NULL) {
 762                                 fprintf(stderr,
 763                                         "ERROR: duplicate certificate chain\n");
 764                                 usage_server();
 765                                 goto server_exit_error;
 766                         }
 767                         arg = argv[i];
 768                         chain = read_certificates(arg, &chain_len);
 769                         if (chain == NULL || chain_len == 0) {
 770                                 goto server_exit_error;
 771                         }
 772                 } else if (eqstr(arg, "-key")) {
 773                         if (++ i >= argc) {
 774                                 fprintf(stderr,
 775                                         "ERROR: no argument for '-key'\n");
 776                                 usage_server();
 777                                 goto server_exit_error;
 778                         }
 779                         if (sk != NULL) {
 780                                 fprintf(stderr,
 781                                         "ERROR: duplicate private key\n");
 782                                 usage_server();
 783                                 goto server_exit_error;
 784                         }
 785                         arg = argv[i];
 786                         sk = read_private_key(arg);
 787                         if (sk == NULL) {
 788                                 goto server_exit_error;
 789                         }
 790                 } else if (eqstr(arg, "-CA")) {
 791                         if (++ i >= argc) {
 792                                 fprintf(stderr,
 793                                         "ERROR: no argument for '-CA'\n");
 794                                 usage_server();
 795                                 goto server_exit_error;
 796                         }
 797                         arg = argv[i];
 798                         if (read_trust_anchors(&anchors, arg) == 0) {
 799                                 usage_server();
 800                                 goto server_exit_error;
 801                         }
 802                 } else if (eqstr(arg, "-anon_ok")) {
 803                         flags |= BR_OPT_TOLERATE_NO_CLIENT_AUTH;
 804                 } else if (eqstr(arg, "-list")) {
 805                         list_names();
 806                         goto server_exit;
 807                 } else if (eqstr(arg, "-vmin")) {
 808                         if (++ i >= argc) {
 809                                 fprintf(stderr,
 810                                         "ERROR: no argument for '-vmin'\n");
 811                                 usage_server();
 812                                 goto server_exit_error;
 813                         }
 814                         arg = argv[i];
 815                         if (vmin != 0) {
 816                                 fprintf(stderr,
 817                                         "ERROR: duplicate minimum version\n");
 818                                 usage_server();
 819                                 goto server_exit_error;
 820                         }
 821                         vmin = parse_version(arg, strlen(arg));
 822                         if (vmin == 0) {
 823                                 fprintf(stderr,
 824                                         "ERROR: unrecognised version '%s'\n",
 825                                         arg);
 826                                 usage_server();
 827                                 goto server_exit_error;
 828                         }
 829                 } else if (eqstr(arg, "-vmax")) {
 830                         if (++ i >= argc) {
 831                                 fprintf(stderr,
 832                                         "ERROR: no argument for '-vmax'\n");
 833                                 usage_server();
 834                                 goto server_exit_error;
 835                         }
 836                         arg = argv[i];
 837                         if (vmax != 0) {
 838                                 fprintf(stderr,
 839                                         "ERROR: duplicate maximum version\n");
 840                                 usage_server();
 841                                 goto server_exit_error;
 842                         }
 843                         vmax = parse_version(arg, strlen(arg));
 844                         if (vmax == 0) {
 845                                 fprintf(stderr,
 846                                         "ERROR: unrecognised version '%s'\n",
 847                                         arg);
 848                                 usage_server();
 849                                 goto server_exit_error;
 850                         }
 851                 } else if (eqstr(arg, "-cs")) {
 852                         if (++ i >= argc) {
 853                                 fprintf(stderr,
 854                                         "ERROR: no argument for '-cs'\n");
 855                                 usage_server();
 856                                 goto server_exit_error;
 857                         }
 858                         arg = argv[i];
 859                         if (suites != NULL) {
 860                                 fprintf(stderr, "ERROR: duplicate list"
 861                                         " of cipher suites\n");
 862                                 usage_server();
 863                                 goto server_exit_error;
 864                         }
 865                         suites = parse_suites(arg, &num_suites);
 866                         if (suites == NULL) {
 867                                 usage_server();
 868                                 goto server_exit_error;
 869                         }
 870                 } else if (eqstr(arg, "-hf")) {
 871                         unsigned x;
 872
 873                         if (++ i >= argc) {
 874                                 fprintf(stderr,
 875                                         "ERROR: no argument for '-hf'\n");
 876                                 usage_server();
 877                                 goto server_exit_error;
 878                         }
 879                         arg = argv[i];
 880                         x = parse_hash_functions(arg);
 881                         if (x == 0) {
 882                                 usage_server();
 883                                 goto server_exit_error;
 884                         }
 885                         hfuns |= x;
 886                 } else if (eqstr(arg, "-cbhash")) {
 887                         cbhash = 1;
 888                 } else if (eqstr(arg, "-serverpref")) {
 889                         flags |= BR_OPT_ENFORCE_SERVER_PREFERENCES;
 890                 } else if (eqstr(arg, "-noreneg")) {
 891                         flags |= BR_OPT_NO_RENEGOTIATION;
 892                 } else if (eqstr(arg, "-alpn")) {
 893                         if (++ i >= argc) {
 894                                 fprintf(stderr,
 895                                         "ERROR: no argument for '-alpn'\n");
 896                                 usage_server();
 897                                 goto server_exit_error;
 898                         }
 899                         VEC_ADD(alpn_names, xstrdup(argv[i]));
 900                 } else if (eqstr(arg, "-strictalpn")) {
 901                         flags |= BR_OPT_FAIL_ON_ALPN_MISMATCH;
 902                 } else {
 903                         fprintf(stderr, "ERROR: unknown option: '%s'\n", arg);
 904                         usage_server();
 905                         goto server_exit_error;
 906                 }
 907         }
 908         if (port == NULL) {
 909                 port = "4433";
 910         }
 911         if (vmin == 0) {
 912                 vmin = BR_TLS10;
 913         }
 914         if (vmax == 0) {
 915                 vmax = BR_TLS12;
 916         }
 917         if (vmax < vmin) {
 918                 fprintf(stderr, "ERROR: impossible minimum/maximum protocol"
 919                         " version combination\n");
 920                 usage_server();
 921                 goto server_exit_error;
 922         }
 923         if (suites == NULL) {
 924                 num_suites = 0;
 925
 926                 for (u = 0; cipher_suites[u].name; u ++) {
 927                         if ((cipher_suites[u].req & REQ_TLS12) == 0
 928                                 || vmax >= BR_TLS12)
 929                         {
 930                                 num_suites ++;
 931                         }
 932                 }
 933                 suites = xmalloc(num_suites * sizeof *suites);
 934                 num_suites = 0;
 935                 for (u = 0; cipher_suites[u].name; u ++) {
 936                         if ((cipher_suites[u].req & REQ_TLS12) == 0
 937                                 || vmax >= BR_TLS12)
 938                         {
 939                                 suites[num_suites ++] = cipher_suites[u];
 940                         }
 941                 }
 942         }
 943         if (hfuns == 0) {
 944                 hfuns = (unsigned)-1;
 945         }
 946         if (chain == NULL || chain_len == 0) {
 947                 fprintf(stderr, "ERROR: no certificate chain provided\n");
 948                 goto server_exit_error;
 949         }
 950         if (sk == NULL) {
 951                 fprintf(stderr, "ERROR: no private key provided\n");
 952                 goto server_exit_error;
 953         }
 954         switch (sk->key_type) {
 955                 int curve;
 956                 uint32_t supp;
 957
 958         case BR_KEYTYPE_RSA:
 959                 break;
 960         case BR_KEYTYPE_EC:
 961                 curve = sk->key.ec.curve;
 962                 supp = br_ec_get_default()->supported_curves;
 963                 if (curve > 31 || !((supp >> curve) & 1)) {
 964                         fprintf(stderr, "ERROR: private key curve (%d)"
 965                                 " is not supported\n", curve);
 966                         goto server_exit_error;
 967                 }
 968                 break;
 969         default:
 970                 fprintf(stderr, "ERROR: unsupported private key type (%d)\n",
 971                         sk->key_type);
 972                 break;
 973         }
 974         cert_signer_algo = get_cert_signer_algo(chain);
 975         if (cert_signer_algo == 0) {
 976                 goto server_exit_error;
 977         }
 978         if (verbose) {
 979                 const char *csas;
 980
 981                 switch (cert_signer_algo) {
 982                 case BR_KEYTYPE_RSA: csas = "RSA"; break;
 983                 case BR_KEYTYPE_EC:  csas = "EC"; break;
 984                 default:
 985                         csas = "unknown";
 986                         break;
 987                 }
 988                 fprintf(stderr, "Issuing CA key type: %d (%s)\n",
 989                         cert_signer_algo, csas);
 990         }
 991         if (iobuf_len == 0) {
 992                 if (bidi) {
 993                         iobuf_len = BR_SSL_BUFSIZE_BIDI;
 994                 } else {
 995                         iobuf_len = BR_SSL_BUFSIZE_MONO;
 996                 }
 997         }
 998         iobuf = xmalloc(iobuf_len);
 999         if (cache_len == (size_t)-1) {
1000                 cache_len = 5000;
1001         }
1002         cache = xmalloc(cache_len);
1003
1004         /*
1005          * Compute implementation requirements and inject implementations.
1006          */
1007         suite_ids = xmalloc(num_suites * sizeof *suite_ids);
1008         br_ssl_server_zero(&cc);
1009         br_ssl_engine_set_versions(&cc.eng, vmin, vmax);
1010         br_ssl_engine_set_all_flags(&cc.eng, flags);
1011         if (vmin <= BR_TLS11) {
1012                 if (!(hfuns & (1 << br_md5_ID))) {
1013                         fprintf(stderr, "ERROR: TLS 1.0 and 1.1 need MD5\n");
1014                         goto server_exit_error;
1015                 }
1016                 if (!(hfuns & (1 << br_sha1_ID))) {
1017                         fprintf(stderr, "ERROR: TLS 1.0 and 1.1 need SHA-1\n");
1018                         goto server_exit_error;
1019                 }
1020         }
1021         for (u = 0; u < num_suites; u ++) {
1022                 unsigned req;
1023
1024                 req = suites[u].req;
1025                 suite_ids[u] = suites[u].suite;
1026                 if ((req & REQ_TLS12) != 0 && vmax < BR_TLS12) {
1027                         fprintf(stderr,
1028                                 "ERROR: cipher suite %s requires TLS 1.2\n",
1029                                 suites[u].name);
1030                         goto server_exit_error;
1031                 }
1032                 if ((req & REQ_SHA1) != 0 && !(hfuns & (1 << br_sha1_ID))) {
1033                         fprintf(stderr,
1034                                 "ERROR: cipher suite %s requires SHA-1\n",
1035                                 suites[u].name);
1036                         goto server_exit_error;
1037                 }
1038                 if ((req & REQ_SHA256) != 0 && !(hfuns & (1 << br_sha256_ID))) {
1039                         fprintf(stderr,
1040                                 "ERROR: cipher suite %s requires SHA-256\n",
1041                                 suites[u].name);
1042                         goto server_exit_error;
1043                 }
1044                 if ((req & REQ_SHA384) != 0 && !(hfuns & (1 << br_sha384_ID))) {
1045                         fprintf(stderr,
1046                                 "ERROR: cipher suite %s requires SHA-384\n",
1047                                 suites[u].name);
1048                         goto server_exit_error;
1049                 }
1050                 /* TODO: algorithm implementation selection */
1051                 if ((req & REQ_AESCBC) != 0) {
1052                         br_ssl_engine_set_default_aes_cbc(&cc.eng);
1053                 }
1054                 if ((req & REQ_AESGCM) != 0) {
1055                         br_ssl_engine_set_default_aes_gcm(&cc.eng);
1056                 }
1057                 if ((req & REQ_CHAPOL) != 0) {
1058                         br_ssl_engine_set_default_chapol(&cc.eng);
1059                 }
1060                 if ((req & REQ_3DESCBC) != 0) {
1061                         br_ssl_engine_set_default_des_cbc(&cc.eng);
1062                 }
1063                 if ((req & (REQ_ECDHE_RSA | REQ_ECDHE_ECDSA)) != 0) {
1064                         br_ssl_engine_set_default_ec(&cc.eng);
1065                 }
1066         }
1067         br_ssl_engine_set_suites(&cc.eng, suite_ids, num_suites);
1068
1069         dnhash = NULL;
1070         for (u = 0; hash_functions[u].name; u ++) {
1071                 const br_hash_class *hc;
1072                 int id;
1073
1074                 hc = hash_functions[u].hclass;
1075                 id = (hc->desc >> BR_HASHDESC_ID_OFF) & BR_HASHDESC_ID_MASK;
1076                 if ((hfuns & ((unsigned)1 << id)) != 0) {
1077                         dnhash = hc;
1078                         br_ssl_engine_set_hash(&cc.eng, id, hc);
1079                 }
1080         }
1081         if (vmin <= BR_TLS11) {
1082                 br_ssl_engine_set_prf10(&cc.eng, &br_tls10_prf);
1083         }
1084         if (vmax >= BR_TLS12) {
1085                 if ((hfuns & ((unsigned)1 << br_sha256_ID)) != 0) {
1086                         br_ssl_engine_set_prf_sha256(&cc.eng,
1087                                 &br_tls12_sha256_prf);
1088                 }
1089                 if ((hfuns & ((unsigned)1 << br_sha384_ID)) != 0) {
1090                         br_ssl_engine_set_prf_sha384(&cc.eng,
1091                                 &br_tls12_sha384_prf);
1092                 }
1093         }
1094
1095         br_ssl_session_cache_lru_init(&lru, cache, cache_len);
1096         br_ssl_server_set_cache(&cc, &lru.vtable);
1097
1098         if (VEC_LEN(alpn_names) != 0) {
1099                 br_ssl_engine_set_protocol_names(&cc.eng,
1100                         (const char **)&VEC_ELT(alpn_names, 0),
1101                         VEC_LEN(alpn_names));
1102         }
1103
1104         /*
1105          * Set the policy handler (that chooses the actual cipher suite,
1106          * selects the certificate chain, and runs the private key
1107          * operations).
1108          */
1109         pc.vtable = &policy_vtable;
1110         pc.verbose = verbose;
1111         pc.chain = chain;
1112         pc.chain_len = chain_len;
1113         pc.cert_signer_algo = cert_signer_algo;
1114         pc.sk = sk;
1115         pc.cbhash = cbhash;
1116         br_ssl_server_set_policy(&cc, &pc.vtable);
1117
1118         /*
1119          * If trust anchors have been configured, then set an X.509
1120          * validation engine and activate client certificate
1121          * authentication.
1122          */
1123         if (VEC_LEN(anchors) != 0) {
1124                 br_x509_minimal_init(&xc, dnhash,
1125                         &VEC_ELT(anchors, 0), VEC_LEN(anchors));
1126                 for (u = 0; hash_functions[u].name; u ++) {
1127                         const br_hash_class *hc;
1128                         int id;
1129
1130                         hc = hash_functions[u].hclass;
1131                         id = (hc->desc >> BR_HASHDESC_ID_OFF)
1132                                 & BR_HASHDESC_ID_MASK;
1133                         if ((hfuns & ((unsigned)1 << id)) != 0) {
1134                                 br_x509_minimal_set_hash(&xc, id, hc);
1135                         }
1136                 }
1137                 br_ssl_engine_set_default_rsavrfy(&cc.eng);
1138                 br_ssl_engine_set_default_ecdsa(&cc.eng);
1139                 br_x509_minimal_set_rsa(&xc, br_rsa_pkcs1_vrfy_get_default());
1140                 br_x509_minimal_set_ecdsa(&xc,
1141                         br_ec_get_default(), br_ecdsa_vrfy_asn1_get_default());
1142                 br_ssl_engine_set_x509(&cc.eng, &xc.vtable);
1143                 br_ssl_server_set_trust_anchor_names_alt(&cc,
1144                         &VEC_ELT(anchors, 0), VEC_LEN(anchors));
1145         }
1146
1147         br_ssl_engine_set_buffer(&cc.eng, iobuf, iobuf_len, bidi);
1148
1149         /*
1150          * On Unix systems, we need to ignore SIGPIPE.
1151          */
1152 #ifndef _WIN32
1153         signal(SIGPIPE, SIG_IGN);
1154 #endif
1155
1156         /*
1157          * Open the server socket.
1158          */
1159         server_fd = host_bind(bind_name, port, verbose);
1160         if (server_fd == INVALID_SOCKET) {
1161                 goto server_exit_error;
1162         }
1163
1164         /*
1165          * Process incoming clients, one at a time. Note that we do not
1166          * accept any client until the previous connection has finished:
1167          * this is voluntary, since the tool uses stdin/stdout for
1168          * application data, and thus cannot really run two connections
1169          * simultaneously.
1170          */
1171         for (;;) {
1172                 int x;
1173
1174                 fd = accept_client(server_fd, verbose);
1175                 if (fd == INVALID_SOCKET) {
1176                         goto server_exit_error;
1177                 }
1178                 br_ssl_server_reset(&cc);
1179                 x = run_ssl_engine(&cc.eng, fd,
1180                         (verbose ? RUN_ENGINE_VERBOSE : 0)
1181                         | (trace ? RUN_ENGINE_TRACE : 0));
1182 #ifdef _WIN32
1183                 closesocket(fd);
1184 #else
1185                 close(fd);
1186 #endif
1187                 fd = INVALID_SOCKET;
1188                 if (x < -1) {
1189                         goto server_exit_error;
1190                 }
1191         }
1192
1193         /*
1194          * Release allocated structures.
1195          */
1196 server_exit:
1197         xfree(suites);
1198         xfree(suite_ids);
1199         free_certificates(chain, chain_len);
1200         free_private_key(sk);
1201         VEC_CLEAREXT(anchors, &free_ta_contents);
1202         VEC_CLEAREXT(alpn_names, &free_alpn);
1203         xfree(iobuf);
1204         xfree(cache);
1205         if (fd != INVALID_SOCKET) {
1206 #ifdef _WIN32
1207                 closesocket(fd);
1208 #else
1209                 close(fd);
1210 #endif
1211         }
1212         return retcode;
1213
1214 server_exit_error:
1215         retcode = -1;
1216         goto server_exit;
1217 }