libratbox/src/gnutls.c

   1 /*
   2  *  libratbox: a library used by ircd-ratbox and other things
   3  *  gnutls.c: gnutls related code
   4  *
   5  *  Copyright (C) 2007-2008 ircd-ratbox development team
   6  *  Copyright (C) 2007-2008 Aaron Sethman <androsyn@ratbox.org>
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
  21  *  USA
  22  *
  23  *  $Id: gnutls.c 26296 2008-12-13 03:36:00Z androsyn $
  24  */
  25
  26 #include <libratbox_config.h>
  27 #include <ratbox_lib.h>
  28 #include <commio-int.h>
  29 #include <commio-ssl.h>
  30 #ifdef HAVE_GNUTLS
  31
  32 #include <gnutls/gnutls.h>
  33 #include <gcrypt.h>
  34
  35 static gnutls_certificate_credentials x509;
  36 static gnutls_dh_params dh_params;
  37
  38
  39
  40 #define SSL_P(x) *((gnutls_session_t *)F->ssl)
  41
  42 void
  43 rb_ssl_shutdown(rb_fde_t *F)
  44 {
  45         int i;
  46         if(F == NULL || F->ssl == NULL)
  47                 return;
  48         for(i = 0; i < 4; i++)
  49         {
  50                 if(gnutls_bye(SSL_P(F), GNUTLS_SHUT_RDWR) == GNUTLS_E_SUCCESS)
  51                         break;
  52         }
  53         gnutls_deinit(SSL_P(F));
  54         rb_free(F->ssl);
  55 }
  56
  57 unsigned int
  58 rb_ssl_handshake_count(rb_fde_t *F)
  59 {
  60         return F->handshake_count;
  61 }
  62
  63 void
  64 rb_ssl_clear_handshake_count(rb_fde_t *F)
  65 {
  66         F->handshake_count = 0;
  67 }
  68
  69 static void
  70 rb_ssl_timeout(rb_fde_t *F, void *notused)
  71 {
  72         lrb_assert(F->accept != NULL);
  73         F->accept->callback(F, RB_ERR_TIMEOUT, NULL, 0, F->accept->data);
  74 }
  75
  76
  77 static int
  78 do_ssl_handshake(rb_fde_t *F, PF * callback)
  79 {
  80         int ret;
  81         int flags;
  82
  83         ret = gnutls_handshake(SSL_P(F));
  84         if(ret < 0)
  85         {
  86                 if((ret == GNUTLS_E_INTERRUPTED && rb_ignore_errno(errno)) || ret == GNUTLS_E_AGAIN)
  87                 {
  88                         if(gnutls_record_get_direction(SSL_P(F)) == 0)
  89                                 flags = RB_SELECT_READ;
  90                         else
  91                                 flags = RB_SELECT_WRITE;
  92                         rb_setselect(F, flags, callback, NULL);
  93                         return 0;
  94                 }
  95                 F->ssl_errno = ret;
  96                 return -1;
  97         }
  98         return 1;               /* handshake is finished..go about life */
  99 }
 100
 101 static void
 102 rb_ssl_tryaccept(rb_fde_t *F, void *data)
 103 {
 104         int ret;
 105         struct acceptdata *ad;
 106
 107         lrb_assert(F->accept != NULL);
 108
 109         ret = do_ssl_handshake(F, rb_ssl_tryaccept);
 110
 111         /* do_ssl_handshake does the rb_setselect */
 112         if(ret == 0)
 113                 return;
 114
 115         ad = F->accept;
 116         F->accept = NULL;
 117         rb_settimeout(F, 0, NULL, NULL);
 118         rb_setselect(F, RB_SELECT_READ | RB_SELECT_WRITE, NULL, NULL);
 119
 120         if(ret > 0)
 121                 ad->callback(F, RB_OK, (struct sockaddr *)&ad->S, ad->addrlen, ad->data);
 122         else
 123                 ad->callback(F, RB_ERROR_SSL, NULL, 0, ad->data);
 124
 125         rb_free(ad);
 126 }
 127
 128 void
 129 rb_ssl_start_accepted(rb_fde_t *new_F, ACCB * cb, void *data, int timeout)
 130 {
 131         gnutls_session_t *ssl;
 132         new_F->type |= RB_FD_SSL;
 133         ssl = new_F->ssl = rb_malloc(sizeof(gnutls_session_t));
 134         new_F->accept = rb_malloc(sizeof(struct acceptdata));
 135
 136         new_F->accept->callback = cb;
 137         new_F->accept->data = data;
 138         rb_settimeout(new_F, timeout, rb_ssl_timeout, NULL);
 139
 140         new_F->accept->addrlen = 0;
 141
 142         gnutls_init(ssl, GNUTLS_SERVER);
 143         gnutls_set_default_priority(*ssl);
 144         gnutls_credentials_set(*ssl, GNUTLS_CRD_CERTIFICATE, x509);
 145         gnutls_dh_set_prime_bits(*ssl, 1024);
 146         gnutls_transport_set_ptr(*ssl, (gnutls_transport_ptr_t) (long int)new_F->fd);
 147         if(do_ssl_handshake(new_F, rb_ssl_tryaccept))
 148         {
 149                 struct acceptdata *ad = new_F->accept;
 150                 new_F->accept = NULL;
 151                 ad->callback(new_F, RB_OK, (struct sockaddr *)&ad->S, ad->addrlen, ad->data);
 152                 rb_free(ad);
 153         }
 154
 155 }
 156
 157
 158
 159
 160 void
 161 rb_ssl_accept_setup(rb_fde_t *F, rb_fde_t *new_F, struct sockaddr *st, int addrlen)
 162 {
 163         new_F->type |= RB_FD_SSL;
 164         new_F->ssl = rb_malloc(sizeof(gnutls_session_t));
 165         new_F->accept = rb_malloc(sizeof(struct acceptdata));
 166
 167         new_F->accept->callback = F->accept->callback;
 168         new_F->accept->data = F->accept->data;
 169         rb_settimeout(new_F, 10, rb_ssl_timeout, NULL);
 170         memcpy(&new_F->accept->S, st, addrlen);
 171         new_F->accept->addrlen = addrlen;
 172
 173         gnutls_init((gnutls_session_t *) new_F->ssl, GNUTLS_SERVER);
 174         gnutls_set_default_priority(SSL_P(new_F));
 175         gnutls_credentials_set(SSL_P(new_F), GNUTLS_CRD_CERTIFICATE, x509);
 176         gnutls_dh_set_prime_bits(SSL_P(new_F), 1024);
 177         gnutls_transport_set_ptr(SSL_P(new_F), (gnutls_transport_ptr_t) (long int)rb_get_fd(new_F));
 178         if(do_ssl_handshake(F, rb_ssl_tryaccept))
 179         {
 180                 struct acceptdata *ad = F->accept;
 181                 F->accept = NULL;
 182                 ad->callback(F, RB_OK, (struct sockaddr *)&ad->S, ad->addrlen, ad->data);
 183                 rb_free(ad);
 184         }
 185 }
 186
 187
 188
 189
 190 static ssize_t
 191 rb_ssl_read_or_write(int r_or_w, rb_fde_t *F, void *rbuf, const void *wbuf, size_t count)
 192 {
 193         ssize_t ret;
 194         gnutls_session_t *ssl = F->ssl;
 195
 196         if(r_or_w == 0)
 197                 ret = gnutls_record_recv(*ssl, rbuf, count);
 198         else
 199                 ret = gnutls_record_send(*ssl, wbuf, count);
 200
 201         if(ret < 0)
 202         {
 203                 switch (ret)
 204                 {
 205                 case GNUTLS_E_AGAIN:
 206                 case GNUTLS_E_INTERRUPTED:
 207                         if(rb_ignore_errno(errno))
 208                         {
 209                                 if(gnutls_record_get_direction(*ssl) == 0)
 210                                         return RB_RW_SSL_NEED_READ;
 211                                 else
 212                                         return RB_RW_SSL_NEED_WRITE;
 213                                 break;
 214                         }
 215                 default:
 216                         F->ssl_errno = ret;
 217                         errno = EIO;
 218                         return RB_RW_IO_ERROR;
 219                 }
 220         }
 221         return ret;
 222 }
 223
 224 ssize_t
 225 rb_ssl_read(rb_fde_t *F, void *buf, size_t count)
 226 {
 227         return rb_ssl_read_or_write(0, F, buf, NULL, count);
 228 }
 229
 230 ssize_t
 231 rb_ssl_write(rb_fde_t *F, const void *buf, size_t count)
 232 {
 233         return rb_ssl_read_or_write(1, F, NULL, buf, count);
 234 }
 235
 236 static void
 237 rb_gcry_random_seed(void *unused)
 238 {
 239         gcry_fast_random_poll();
 240 }
 241
 242 int
 243 rb_init_ssl(void)
 244 {
 245         gnutls_global_init();
 246
 247         if(gnutls_certificate_allocate_credentials(&x509) != GNUTLS_E_SUCCESS)
 248         {
 249                 rb_lib_log("rb_init_ssl: Unable to allocate SSL/TLS certificate credentials");
 250                 return 0;
 251         }
 252         rb_event_addish("rb_gcry_random_seed", rb_gcry_random_seed, NULL, 300);
 253         return 1;
 254 }
 255
 256 static void
 257 rb_free_datum_t(gnutls_datum_t * d)
 258 {
 259         rb_free(d->data);
 260         rb_free(d);
 261 }
 262
 263 static gnutls_datum_t *
 264 rb_load_file_into_datum_t(const char *file)
 265 {
 266         FILE *f;
 267         gnutls_datum_t *datum;
 268         struct stat fileinfo;
 269         if((f = fopen(file, "r")) == NULL)
 270                 return NULL;
 271         if(fstat(fileno(f), &fileinfo))
 272                 return NULL;
 273
 274         datum = rb_malloc(sizeof(gnutls_datum_t));
 275
 276         if(fileinfo.st_size > 131072)   /* deal with retards */
 277                 datum->size = 131072;
 278         else
 279                 datum->size = fileinfo.st_size;
 280
 281         datum->data = rb_malloc(datum->size + 1);
 282         fread(datum->data, datum->size, 1, f);
 283         fclose(f);
 284         return datum;
 285 }
 286
 287 int
 288 rb_setup_ssl_server(const char *cert, const char *keyfile, const char *dhfile)
 289 {
 290         int ret;
 291         gnutls_datum_t *d_cert, *d_key;
 292         if(cert == NULL)
 293         {
 294                 rb_lib_log("rb_setup_ssl_server: No certificate file");
 295                 return 0;
 296         }
 297
 298         if((d_cert = rb_load_file_into_datum_t(cert)) == NULL)
 299         {
 300                 rb_lib_log("rb_setup_ssl_server: Error loading certificate: %s", strerror(errno));
 301                 return 0;
 302         }
 303
 304         if((d_key = rb_load_file_into_datum_t(keyfile)) == NULL)
 305         {
 306                 rb_lib_log("rb_setup_ssl_server: Error loading key: %s", strerror(errno));
 307                 return 0;
 308         }
 309
 310
 311         if((ret =
 312             gnutls_certificate_set_x509_key_mem(x509, d_cert, d_key,
 313                                                 GNUTLS_X509_FMT_PEM)) != GNUTLS_E_SUCCESS)
 314         {
 315                 rb_lib_log("rb_setup_ssl_server: Error loading certificate or key file: %s",
 316                            gnutls_strerror(ret));
 317                 return 0;
 318         }
 319         rb_free_datum_t(d_cert);
 320         rb_free_datum_t(d_key);
 321
 322         if(dhfile != NULL)
 323         {
 324                 if(gnutls_dh_params_init(&dh_params) == GNUTLS_E_SUCCESS)
 325                 {
 326                         gnutls_datum_t *data;
 327                         int xret;
 328                         data = rb_load_file_into_datum_t(dhfile);
 329                         if(data != NULL)
 330                         {
 331                                 xret = gnutls_dh_params_import_pkcs3(dh_params, data,
 332                                                                      GNUTLS_X509_FMT_PEM);
 333                                 if(xret < 0)
 334                                         rb_lib_log
 335                                                 ("rb_setup_ssl_server: Error parsing DH file: %s\n",
 336                                                  gnutls_strerror(xret));
 337                                 rb_free_datum_t(data);
 338                         }
 339                         gnutls_certificate_set_dh_params(x509, dh_params);
 340                 }
 341                 else
 342                         rb_lib_log("rb_setup_ssl_server: Unable to setup DH parameters");
 343         }
 344         return 1;
 345 }
 346
 347 int
 348 rb_ssl_listen(rb_fde_t *F, int backlog)
 349 {
 350         F->type = RB_FD_SOCKET | RB_FD_LISTEN | RB_FD_SSL;
 351         return listen(F->fd, backlog);
 352 }
 353
 354 struct ssl_connect
 355 {
 356         CNCB *callback;
 357         void *data;
 358         int timeout;
 359 };
 360
 361 static void
 362 rb_ssl_connect_realcb(rb_fde_t *F, int status, struct ssl_connect *sconn)
 363 {
 364         F->connect->callback = sconn->callback;
 365         F->connect->data = sconn->data;
 366         rb_free(sconn);
 367         rb_connect_callback(F, status);
 368 }
 369
 370 static void
 371 rb_ssl_tryconn_timeout_cb(rb_fde_t *F, void *data)
 372 {
 373         rb_ssl_connect_realcb(F, RB_ERR_TIMEOUT, data);
 374 }
 375
 376 static void
 377 rb_ssl_tryconn_cb(rb_fde_t *F, void *data)
 378 {
 379         struct ssl_connect *sconn = data;
 380         int ret;
 381
 382         ret = do_ssl_handshake(F, rb_ssl_tryconn_cb);
 383
 384         switch (ret)
 385         {
 386         case -1:
 387                 rb_ssl_connect_realcb(F, RB_ERROR_SSL, sconn);
 388                 break;
 389         case 0:
 390                 /* do_ssl_handshake does the rb_setselect stuff */
 391                 return;
 392         default:
 393                 break;
 394
 395
 396         }
 397         rb_ssl_connect_realcb(F, RB_OK, sconn);
 398 }
 399
 400 static void
 401 rb_ssl_tryconn(rb_fde_t *F, int status, void *data)
 402 {
 403         struct ssl_connect *sconn = data;
 404         if(status != RB_OK)
 405         {
 406                 rb_ssl_connect_realcb(F, status, sconn);
 407                 return;
 408         }
 409
 410         F->type |= RB_FD_SSL;
 411
 412
 413         rb_settimeout(F, sconn->timeout, rb_ssl_tryconn_timeout_cb, sconn);
 414         F->ssl = rb_malloc(sizeof(gnutls_session_t));
 415         gnutls_init(F->ssl, GNUTLS_CLIENT);
 416         gnutls_set_default_priority(SSL_P(F));
 417         gnutls_dh_set_prime_bits(SSL_P(F), 1024);
 418         gnutls_transport_set_ptr(SSL_P(F), (gnutls_transport_ptr_t) (long int)F->fd);
 419
 420         if(do_ssl_handshake(F, rb_ssl_tryconn_cb))
 421         {
 422                 rb_ssl_connect_realcb(F, RB_OK, sconn);
 423         }
 424 }
 425
 426 void
 427 rb_connect_tcp_ssl(rb_fde_t *F, struct sockaddr *dest,
 428                    struct sockaddr *clocal, int socklen, CNCB * callback, void *data, int timeout)
 429 {
 430         struct ssl_connect *sconn;
 431         if(F == NULL)
 432                 return;
 433
 434         sconn = rb_malloc(sizeof(struct ssl_connect));
 435         sconn->data = data;
 436         sconn->callback = callback;
 437         sconn->timeout = timeout;
 438         rb_connect_tcp(F, dest, clocal, socklen, rb_ssl_tryconn, sconn, timeout);
 439
 440 }
 441
 442 void
 443 rb_ssl_start_connected(rb_fde_t *F, CNCB * callback, void *data, int timeout)
 444 {
 445         struct ssl_connect *sconn;
 446         if(F == NULL)
 447                 return;
 448
 449         sconn = rb_malloc(sizeof(struct ssl_connect));
 450         sconn->data = data;
 451         sconn->callback = callback;
 452         sconn->timeout = timeout;
 453         F->connect = rb_malloc(sizeof(struct conndata));
 454         F->connect->callback = callback;
 455         F->connect->data = data;
 456         F->type |= RB_FD_SSL;
 457         F->ssl = rb_malloc(sizeof(gnutls_session_t));
 458
 459         gnutls_init(F->ssl, GNUTLS_CLIENT);
 460         gnutls_set_default_priority(SSL_P(F));
 461         gnutls_dh_set_prime_bits(SSL_P(F), 1024);
 462         gnutls_transport_set_ptr(SSL_P(F), (gnutls_transport_ptr_t) (long int)F->fd);
 463
 464         rb_settimeout(F, sconn->timeout, rb_ssl_tryconn_timeout_cb, sconn);
 465
 466         if(do_ssl_handshake(F, rb_ssl_tryconn_cb))
 467         {
 468                 rb_ssl_connect_realcb(F, RB_OK, sconn);
 469         }
 470 }
 471
 472 int
 473 rb_init_prng(const char *path, prng_seed_t seed_type)
 474 {
 475         gcry_fast_random_poll();
 476         return 1;
 477 }
 478
 479 int
 480 rb_get_random(void *buf, size_t length)
 481 {
 482         gcry_randomize(buf, length, GCRY_STRONG_RANDOM);
 483         return 1;
 484 }
 485
 486 int
 487 rb_get_pseudo_random(void *buf, size_t length)
 488 {
 489         gcry_randomize(buf, length, GCRY_WEAK_RANDOM);
 490         return 1;
 491 }
 492
 493 const char *
 494 rb_get_ssl_strerror(rb_fde_t *F)
 495 {
 496         return gnutls_strerror(F->ssl_errno);
 497 }
 498
 499 int
 500 rb_supports_ssl(void)
 501 {
 502         return 1;
 503 }
 504
 505 void
 506 rb_get_ssl_info(char *buf, size_t len)
 507 {
 508         rb_snprintf(buf, len, "GNUTLS: compiled (%s), library(%s)",
 509                     LIBGNUTLS_VERSION, gnutls_check_version(NULL));
 510 }
 511
 512
 513 #endif /* HAVE_GNUTLS */