src/common/ssl_certificate.c

   1 /*
   2  * Claws Mail -- a GTK+ based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2015 Colin Leroy <colin@colino.net>
   4  * and the Claws Mail team
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  18  *
  19  */
  20
  21 #ifdef HAVE_CONFIG_H
  22 #  include "config.h"
  23 #include "claws-features.h"
  24 #endif
  25
  26 #ifdef USE_GNUTLS
  27 #include <gnutls/gnutls.h>
  28 #include <gnutls/x509.h>
  29 #include <gnutls/pkcs12.h>
  30 #include <sys/stat.h>
  31 #include <unistd.h>
  32 #include <string.h>
  33 #include <sys/types.h>
  34 #include <stdio.h>
  35 #include <glib.h>
  36 #include <glib/gi18n.h>
  37 #include <errno.h>
  38 #ifdef G_OS_WIN32
  39 #  include <winsock2.h>
  40 #else
  41 #  include <sys/socket.h>
  42 #  include <netinet/in.h>
  43 #  include <netdb.h>
  44 #endif /* G_OS_WIN32 */
  45 #include "ssl_certificate.h"
  46 #include "utils.h"
  47 #include "log.h"
  48 #include "socket.h"
  49 #include "hooks.h"
  50 #include "defs.h"
  51
  52 static GHashTable *warned_expired = NULL;
  53
  54 gboolean prefs_common_unsafe_ssl_certs(void);
  55
  56 static gchar *get_certificate_path(const gchar *host, const gchar *port, const gchar *fp)
  57 {
  58         if (fp != NULL && prefs_common_unsafe_ssl_certs())
  59                 return g_strconcat(get_rc_dir(), G_DIR_SEPARATOR_S,
  60                           "certs", G_DIR_SEPARATOR_S,
  61                           host, ".", port, ".", fp, ".cert", NULL);
  62         else
  63                 return g_strconcat(get_rc_dir(), G_DIR_SEPARATOR_S,
  64                           "certs", G_DIR_SEPARATOR_S,
  65                           host, ".", port, ".cert", NULL);
  66 }
  67
  68 static gchar *get_certificate_chain_path(const gchar *host, const gchar *port, const gchar *fp)
  69 {
  70         gchar *tmp = get_certificate_path(host, port, fp);
  71         gchar *result = g_strconcat(tmp, ".chain", NULL);
  72
  73         g_free(tmp);
  74
  75         return result;
  76 }
  77
  78 char * readable_fingerprint(unsigned char *src, int len)
  79 {
  80         int i=0;
  81         char * ret;
  82
  83         if (src == NULL)
  84                 return NULL;
  85         ret = g_strdup("");
  86         while (i < len) {
  87                 char *tmp2;
  88                 if(i>0)
  89                         tmp2 = g_strdup_printf("%s:%02X", ret, src[i]);
  90                 else
  91                         tmp2 = g_strdup_printf("%02X", src[i]);
  92                 g_free(ret);
  93                 ret = g_strdup(tmp2);
  94                 g_free(tmp2);
  95                 i++;
  96         }
  97         return ret;
  98 }
  99
 100 #if USE_GNUTLS
 101 static gnutls_x509_crt_t x509_crt_copy(gnutls_x509_crt_t src)
 102 {
 103     int ret;
 104     size_t size;
 105     gnutls_datum_t tmp;
 106     gnutls_x509_crt_t dest;
 107     size = 0;
 108
 109     if (gnutls_x509_crt_init(&dest) != 0) {
 110         g_warning("couldn't gnutls_x509_crt_init\n");
 111         return NULL;
 112     }
 113
 114     if (gnutls_x509_crt_export(src, GNUTLS_X509_FMT_DER, NULL, &size)
 115         != GNUTLS_E_SHORT_MEMORY_BUFFER) {
 116         g_warning("couldn't gnutls_x509_crt_export to get size\n");
 117         gnutls_x509_crt_deinit(dest);
 118         return NULL;
 119     }
 120
 121     tmp.data = malloc(size);
 122     memset(tmp.data, 0, size);
 123     ret = gnutls_x509_crt_export(src, GNUTLS_X509_FMT_DER, tmp.data, &size);
 124     if (ret == 0) {
 125         tmp.size = size;
 126         ret = gnutls_x509_crt_import(dest, &tmp, GNUTLS_X509_FMT_DER);
 127         if (ret) {
 128                 g_warning("couldn't gnutls_x509_crt_import for real (%d %s)\n", ret, gnutls_strerror(ret));
 129                 gnutls_x509_crt_deinit(dest);
 130                 dest = NULL;
 131         }
 132     } else {
 133         g_warning("couldn't gnutls_x509_crt_export for real (%d %s)\n", ret, gnutls_strerror(ret));
 134         gnutls_x509_crt_deinit(dest);
 135         dest = NULL;
 136     }
 137
 138     free(tmp.data);
 139     return dest;
 140 }
 141 #endif
 142
 143 static SSLCertificate *ssl_certificate_new(gnutls_x509_crt_t x509_cert, const gchar *host, gushort port)
 144 {
 145         SSLCertificate *cert = g_new0(SSLCertificate, 1);
 146         size_t n;
 147         unsigned char md[128];
 148
 149         if (host == NULL || x509_cert == NULL) {
 150                 ssl_certificate_destroy(cert);
 151                 return NULL;
 152         }
 153         cert->x509_cert = x509_crt_copy(x509_cert);
 154         cert->status = (guint)-1;
 155         cert->host = g_strdup(host);
 156         cert->port = port;
 157
 158         /* fingerprint */
 159         n = sizeof(md);
 160         gnutls_x509_crt_get_fingerprint(cert->x509_cert, GNUTLS_DIG_MD5, md, &n);
 161         cert->fingerprint = readable_fingerprint(md, (int)n);
 162         return cert;
 163 }
 164
 165 static void gnutls_export_X509_fp(FILE *fp, gnutls_x509_crt_t x509_cert, gnutls_x509_crt_fmt_t format)
 166 {
 167         char output[10*1024];
 168         size_t cert_size = 10*1024;
 169         int r;
 170
 171         if ((r = gnutls_x509_crt_export(x509_cert, format, output, &cert_size)) < 0) {
 172                 g_warning("couldn't export cert %s (%zd)\n", gnutls_strerror(r), cert_size);
 173                 return;
 174         }
 175
 176         debug_print("writing %zd bytes\n",cert_size);
 177         if (fwrite(&output, 1, cert_size, fp) < cert_size) {
 178                 g_warning("failed to write cert: %d %s\n", errno, g_strerror(errno));
 179         }
 180 }
 181
 182 size_t gnutls_i2d_X509(gnutls_x509_crt_t x509_cert, unsigned char **output)
 183 {
 184         size_t cert_size = 10*1024;
 185         int r;
 186
 187         if (output == NULL)
 188                 return 0;
 189
 190         *output = malloc(cert_size);
 191
 192         if ((r = gnutls_x509_crt_export(x509_cert, GNUTLS_X509_FMT_DER, *output, &cert_size)) < 0) {
 193                 g_warning("couldn't export cert %s (%zd)\n", gnutls_strerror(r), cert_size);
 194                 free(*output);
 195                 *output = NULL;
 196                 return 0;
 197         }
 198         return cert_size;
 199 }
 200
 201 size_t gnutls_i2d_PrivateKey(gnutls_x509_privkey_t pkey, unsigned char **output)
 202 {
 203         size_t key_size = 10*1024;
 204         int r;
 205
 206         if (output == NULL)
 207                 return 0;
 208
 209         *output = malloc(key_size);
 210
 211         if ((r = gnutls_x509_privkey_export(pkey, GNUTLS_X509_FMT_DER, *output, &key_size)) < 0) {
 212                 g_warning("couldn't export key %s (%zd)\n", gnutls_strerror(r), key_size);
 213                 free(*output);
 214                 *output = NULL;
 215                 return 0;
 216         }
 217         return key_size;
 218 }
 219
 220 static int gnutls_import_X509_list_fp(FILE *fp, gnutls_x509_crt_fmt_t format,
 221                                    gnutls_x509_crt_t **cert_list, gint *num_certs)
 222 {
 223         gnutls_x509_crt_t *crt_list;
 224         unsigned int max = 512;
 225         unsigned int flags = 0;
 226         gnutls_datum_t tmp;
 227         struct stat s;
 228         int r;
 229
 230         *cert_list = NULL;
 231         *num_certs = 0;
 232
 233         if (fp == NULL)
 234                 return -ENOENT;
 235
 236         if (fstat(fileno(fp), &s) < 0) {
 237                 perror("fstat");
 238                 return -errno;
 239         }
 240
 241         crt_list=(gnutls_x509_crt_t*)malloc(max*sizeof(gnutls_x509_crt_t));
 242         tmp.data = malloc(s.st_size);
 243         memset(tmp.data, 0, s.st_size);
 244         tmp.size = s.st_size;
 245         if (fread (tmp.data, 1, s.st_size, fp) < s.st_size) {
 246                 perror("fread");
 247                 free(tmp.data);
 248                 free(crt_list);
 249                 return -EIO;
 250         }
 251
 252         if ((r = gnutls_x509_crt_list_import(crt_list, &max,
 253                         &tmp, format, flags)) < 0) {
 254                 debug_print("cert import failed: %s\n", gnutls_strerror(r));
 255                 free(tmp.data);
 256                 free(crt_list);
 257                 return r;
 258         }
 259         free(tmp.data);
 260         debug_print("got %d certs in crt_list! %p\n", max, &crt_list);
 261
 262         *cert_list = crt_list;
 263         *num_certs = max;
 264
 265         return r;
 266 }
 267
 268 /* return one certificate, read from file */
 269 static gnutls_x509_crt_t gnutls_import_X509_fp(FILE *fp, gnutls_x509_crt_fmt_t format)
 270 {
 271         gnutls_x509_crt_t *certs = NULL;
 272         gnutls_x509_crt_t cert = NULL;
 273         int i, ncerts, r;
 274
 275         if ((r = gnutls_import_X509_list_fp(fp, format, &certs, &ncerts)) < 0) {
 276                 return NULL;
 277         }
 278
 279         if (ncerts == 0)
 280                 return NULL;
 281
 282         for (i = 1; i < ncerts; i++)
 283                 gnutls_x509_crt_deinit(certs[i]);
 284
 285         cert = certs[0];
 286         free(certs);
 287
 288         return cert;
 289 }
 290
 291 static gnutls_x509_privkey_t gnutls_import_key_fp(FILE *fp, gnutls_x509_crt_fmt_t format)
 292 {
 293         gnutls_x509_privkey_t key = NULL;
 294         gnutls_datum_t tmp;
 295         struct stat s;
 296         int r;
 297         if (fstat(fileno(fp), &s) < 0) {
 298                 perror("fstat");
 299                 return NULL;
 300         }
 301         tmp.data = malloc(s.st_size);
 302         memset(tmp.data, 0, s.st_size);
 303         tmp.size = s.st_size;
 304         if (fread (tmp.data, 1, s.st_size, fp) < s.st_size) {
 305                 perror("fread");
 306                 free(tmp.data);
 307                 return NULL;
 308         }
 309
 310         gnutls_x509_privkey_init(&key);
 311         if ((r = gnutls_x509_privkey_import(key, &tmp, format)) < 0) {
 312                 debug_print("key import failed: %s\n", gnutls_strerror(r));
 313                 gnutls_x509_privkey_deinit(key);
 314                 key = NULL;
 315         }
 316         free(tmp.data);
 317         debug_print("got key! %p\n", key);
 318         return key;
 319 }
 320
 321 static gnutls_pkcs12_t gnutls_import_PKCS12_fp(FILE *fp, gnutls_x509_crt_fmt_t format)
 322 {
 323         gnutls_pkcs12_t p12 = NULL;
 324         gnutls_datum_t tmp;
 325         struct stat s;
 326         int r;
 327         if (fstat(fileno(fp), &s) < 0) {
 328                 log_error(LOG_PROTOCOL, _("Cannot stat P12 certificate file (%s)\n"),
 329                                   g_strerror(errno));
 330                 return NULL;
 331         }
 332         tmp.data = malloc(s.st_size);
 333         memset(tmp.data, 0, s.st_size);
 334         tmp.size = s.st_size;
 335         if (fread (tmp.data, 1, s.st_size, fp) < s.st_size) {
 336                 log_error(LOG_PROTOCOL, _("Cannot read P12 certificate file (%s)\n"),
 337                                   g_strerror(errno));
 338                 free(tmp.data);
 339                 return NULL;
 340         }
 341
 342         gnutls_pkcs12_init(&p12);
 343
 344         if ((r = gnutls_pkcs12_import(p12, &tmp, format, 0)) < 0) {
 345                 log_error(LOG_PROTOCOL, _("Cannot import P12 certificate file (%s)\n"),
 346                                   gnutls_strerror(r));
 347                 gnutls_pkcs12_deinit(p12);
 348                 p12 = NULL;
 349         }
 350         free(tmp.data);
 351         debug_print("got p12! %p\n", p12);
 352         return p12;
 353 }
 354
 355 static void ssl_certificate_save (SSLCertificate *cert)
 356 {
 357         gchar *file, *port;
 358         FILE *fp;
 359
 360         file = g_strconcat(get_rc_dir(), G_DIR_SEPARATOR_S,
 361                           "certs", G_DIR_SEPARATOR_S, NULL);
 362
 363         if (!is_dir_exist(file))
 364                 make_dir_hier(file);
 365         g_free(file);
 366
 367         port = g_strdup_printf("%d", cert->port);
 368         file = get_certificate_path(cert->host, port, cert->fingerprint);
 369
 370         g_free(port);
 371         fp = g_fopen(file, "wb");
 372         if (fp == NULL) {
 373                 g_free(file);
 374                 debug_print("Can't save certificate !\n");
 375                 return;
 376         }
 377
 378         gnutls_export_X509_fp(fp, cert->x509_cert, GNUTLS_X509_FMT_DER);
 379
 380         g_free(file);
 381         fclose(fp);
 382
 383 }
 384
 385 void ssl_certificate_destroy(SSLCertificate *cert)
 386 {
 387         if (cert == NULL)
 388                 return;
 389
 390         if (cert->x509_cert)
 391                 gnutls_x509_crt_deinit(cert->x509_cert);
 392         g_free(cert->host);
 393         g_free(cert->fingerprint);
 394         g_free(cert);
 395         cert = NULL;
 396 }
 397
 398 void ssl_certificate_delete_from_disk(SSLCertificate *cert)
 399 {
 400         gchar *buf;
 401         gchar *file;
 402         buf = g_strdup_printf("%d", cert->port);
 403         file = get_certificate_path(cert->host, buf, cert->fingerprint);
 404         claws_unlink (file);
 405         g_free(file);
 406         file = get_certificate_chain_path(cert->host, buf, cert->fingerprint);
 407         claws_unlink (file);
 408         g_free(file);
 409         g_free(buf);
 410 }
 411
 412 SSLCertificate *ssl_certificate_find (const gchar *host, gushort port, const gchar *fingerprint)
 413 {
 414         gchar *file = NULL;
 415         gchar *buf;
 416         SSLCertificate *cert = NULL;
 417         gnutls_x509_crt_t tmp_x509;
 418         FILE *fp = NULL;
 419         gboolean must_rename = FALSE;
 420
 421         buf = g_strdup_printf("%d", port);
 422
 423         if (fingerprint != NULL) {
 424                 file = get_certificate_path(host, buf, fingerprint);
 425                 fp = g_fopen(file, "rb");
 426         }
 427         if (fp == NULL) {
 428                 /* see if we have the old one */
 429                 debug_print("didn't get %s\n", file);
 430                 g_free(file);
 431                 file = get_certificate_path(host, buf, NULL);
 432                 fp = g_fopen(file, "rb");
 433
 434                 if (fp) {
 435                         debug_print("got %s\n", file);
 436                         must_rename = (fingerprint != NULL);
 437                 }
 438         } else {
 439                 debug_print("got %s first try\n", file);
 440         }
 441         if (fp == NULL) {
 442                 g_free(file);
 443                 g_free(buf);
 444                 return NULL;
 445         }
 446
 447         if ((tmp_x509 = gnutls_import_X509_fp(fp, GNUTLS_X509_FMT_DER)) != NULL) {
 448                 cert = ssl_certificate_new(tmp_x509, host, port);
 449                 debug_print("got cert %p\n", cert);
 450                 gnutls_x509_crt_deinit(tmp_x509);
 451         }
 452
 453         fclose(fp);
 454         g_free(file);
 455
 456         if (must_rename) {
 457                 gchar *old = get_certificate_path(host, buf, NULL);
 458                 gchar *new = get_certificate_path(host, buf, fingerprint);
 459                 if (strcmp(old, new))
 460                         move_file(old, new, TRUE);
 461                 g_free(old);
 462                 g_free(new);
 463         }
 464         g_free(buf);
 465
 466         return cert;
 467 }
 468
 469 static gboolean ssl_certificate_compare (SSLCertificate *cert_a, SSLCertificate *cert_b)
 470 {
 471         char *output_a;
 472         char *output_b;
 473         size_t cert_size_a = 0, cert_size_b = 0;
 474         int r;
 475
 476         if (cert_a == NULL || cert_b == NULL)
 477                 return FALSE;
 478
 479         if ((r = gnutls_x509_crt_export(cert_a->x509_cert, GNUTLS_X509_FMT_DER, NULL, &cert_size_a))
 480             != GNUTLS_E_SHORT_MEMORY_BUFFER) {
 481                 g_warning("couldn't gnutls_x509_crt_export to get size a %s\n", gnutls_strerror(r));
 482                 return FALSE;
 483         }
 484
 485         if ((r = gnutls_x509_crt_export(cert_b->x509_cert, GNUTLS_X509_FMT_DER, NULL, &cert_size_b))
 486             != GNUTLS_E_SHORT_MEMORY_BUFFER) {
 487                 g_warning("couldn't gnutls_x509_crt_export to get size b %s\n", gnutls_strerror(r));
 488                 return FALSE;
 489         }
 490
 491         output_a = g_malloc(cert_size_a);
 492         output_b = g_malloc(cert_size_b);
 493         if ((r = gnutls_x509_crt_export(cert_a->x509_cert, GNUTLS_X509_FMT_DER, output_a, &cert_size_a)) < 0) {
 494                 g_warning("couldn't gnutls_x509_crt_export a %s\n", gnutls_strerror(r));
 495                 g_free(output_a);
 496                 g_free(output_b);
 497                 return FALSE;
 498         }
 499         if ((r = gnutls_x509_crt_export(cert_b->x509_cert, GNUTLS_X509_FMT_DER, output_b, &cert_size_b)) < 0) {
 500                 g_warning("couldn't gnutls_x509_crt_export b %s\n", gnutls_strerror(r));
 501                 g_free(output_a);
 502                 g_free(output_b);
 503                 return FALSE;
 504         }
 505         if (cert_size_a != cert_size_b) {
 506                 g_warning("size differ %zd %zd\n", cert_size_a, cert_size_b);
 507                 g_free(output_a);
 508                 g_free(output_b);
 509                 return FALSE;
 510         }
 511         if (memcmp(output_a, output_b, cert_size_a)) {
 512                 g_warning("contents differ\n");
 513                 g_free(output_a);
 514                 g_free(output_b);
 515                 return FALSE;
 516         }
 517         g_free(output_a);
 518         g_free(output_b);
 519
 520         return TRUE;
 521 }
 522
 523 static guint check_cert(SSLCertificate *cert)
 524 {
 525         gnutls_x509_crt_t *ca_list = NULL;
 526         gnutls_x509_crt_t *chain = NULL;
 527         unsigned int max_ca = 512, max_certs;
 528         unsigned int flags = 0;
 529         int r, i;
 530         unsigned int status;
 531         gchar *chain_file = NULL, *buf = NULL;
 532         FILE *fp;
 533
 534         if (claws_ssl_get_cert_file())
 535                 fp = g_fopen(claws_ssl_get_cert_file(), "r");
 536         else
 537                 return (guint)-1;
 538
 539         if (fp == NULL)
 540                 return (guint)-1;
 541
 542         if ((r = gnutls_import_X509_list_fp(fp, GNUTLS_X509_FMT_PEM, &ca_list, &max_ca)) < 0) {
 543                 debug_print("CA import failed: %s\n", gnutls_strerror(r));
 544                 fclose(fp);
 545                 return (guint)-1;
 546         }
 547         fclose(fp);
 548         fp = NULL;
 549
 550         buf = g_strdup_printf("%d", cert->port);
 551         chain_file = get_certificate_chain_path(cert->host, buf, cert->fingerprint);
 552         g_free(buf);
 553         if (is_file_exist(chain_file)) {
 554                 unsigned char md[128];
 555                 size_t n;
 556                 char *fingerprint;
 557
 558                 fp = g_fopen(chain_file, "r");
 559                 if (fp == NULL) {
 560                         debug_print("fopen %s failed: %s\n", chain_file, g_strerror(errno));
 561                         g_free(chain_file);
 562                         return (guint)-1;
 563                 }
 564                 if ((r = gnutls_import_X509_list_fp(fp, GNUTLS_X509_FMT_PEM, &chain, &max_certs)) < 0) {
 565                         debug_print("chain import failed: %s\n", gnutls_strerror(r));
 566                         fclose(fp);
 567                         g_free(chain_file);
 568                         return (guint)-1;
 569                 }
 570                 g_free(chain_file);
 571                 fclose(fp);
 572                 fp = NULL;
 573
 574                 gnutls_x509_crt_get_fingerprint(chain[0], GNUTLS_DIG_MD5, md, &n);
 575                 fingerprint = readable_fingerprint(md, n);
 576                 if (!fingerprint || strcmp(fingerprint, cert->fingerprint)) {
 577                         debug_print("Saved chain fingerprint does not match current : %s / %s",
 578                                 cert->fingerprint, fingerprint);
 579
 580                         return (guint)-1;
 581                 }
 582                 g_free(fingerprint);
 583
 584                 r = gnutls_x509_crt_list_verify (chain,
 585                                      max_certs,
 586                                      ca_list, max_ca,
 587                                      NULL, 0,
 588                                      GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT,
 589                                      &status);
 590                 if (r < 0)
 591                         debug_print("chain check failed: %s\n", gnutls_strerror(r));
 592
 593                 for (i = 0; i < max_certs; i++)
 594                         gnutls_x509_crt_deinit(chain[i]);
 595                 free(chain);
 596
 597         } else {
 598                 r = gnutls_x509_crt_verify(cert->x509_cert, ca_list, max_ca, flags, &status);
 599                 if (r < 0)
 600                         debug_print("cert check failed: %s\n", gnutls_strerror(r));
 601         }
 602
 603         for (i = 0; i < max_ca; i++)
 604                 gnutls_x509_crt_deinit(ca_list[i]);
 605         free(ca_list);
 606
 607         if (r < 0)
 608                 return (guint)-1;
 609         else
 610                 return status;
 611
 612 }
 613
 614 static gboolean ssl_certificate_is_valid(SSLCertificate *cert, guint status)
 615 {
 616         gchar *str_status = ssl_certificate_check_signer(cert, status);
 617
 618         if (str_status != NULL) {
 619                 g_free(str_status);
 620                 return FALSE;
 621         }
 622         return ssl_certificate_check_subject_cn(cert);
 623 }
 624
 625 char *ssl_certificate_check_signer (SSLCertificate *cert, guint status)
 626 {
 627         gnutls_x509_crt_t x509_cert = cert ? cert->x509_cert : NULL;
 628
 629         if (!cert)
 630                 return g_strdup(_("Internal error"));
 631
 632         if (status == (guint)-1) {
 633                 status = check_cert(cert);
 634                 if (status == -1)
 635                         return g_strdup(_("Uncheckable"));
 636         }
 637         if (status & GNUTLS_CERT_INVALID) {
 638                 if (gnutls_x509_crt_check_issuer(x509_cert, x509_cert))
 639                         return g_strdup(_("Self-signed certificate"));
 640         }
 641         if (status & GNUTLS_CERT_REVOKED)
 642                 return g_strdup(_("Revoked certificate"));
 643         if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 644                 return g_strdup(_("No certificate issuer found"));
 645         if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 646                 return g_strdup(_("Certificate issuer is not a CA"));
 647
 648
 649         return NULL;
 650 }
 651
 652 static void ssl_certificate_save_chain(gnutls_x509_crt_t *certs, gint len, const gchar *host, gushort port)
 653 {
 654         gint i;
 655         gchar *file = NULL;
 656         FILE *fp = NULL;
 657
 658         for (i = 0; i < len; i++) {
 659                 size_t n;
 660                 unsigned char md[128];
 661                 gnutls_x509_crt_t cert = certs[i];
 662                 gchar *fingerprint;
 663
 664                 if (i == 0) {
 665                         n = sizeof(md);
 666                         gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, md, &n);
 667                         fingerprint = readable_fingerprint(md, n);
 668                         gchar *buf = g_strdup_printf("%d", port);
 669
 670                         file = get_certificate_chain_path(host, buf, fingerprint);
 671
 672                         g_free(buf);
 673
 674                         fp = g_fopen(file, "wb");
 675                         if (fp == NULL) {
 676                                 g_free(file);
 677                                 debug_print("Can't save certificate !\n");
 678                                 return;
 679                         }
 680                         g_free(file);
 681                 }
 682
 683                 gnutls_export_X509_fp(fp, cert, GNUTLS_X509_FMT_PEM);
 684
 685         }
 686         if (fp)
 687                 fclose(fp);
 688 }
 689
 690 gboolean ssl_certificate_check (gnutls_x509_crt_t x509_cert, guint status,
 691                                 const gchar *host, gushort port,
 692                                 gboolean accept_if_valid)
 693 {
 694         SSLCertificate *current_cert = NULL;
 695         SSLCertificate *known_cert;
 696         SSLCertHookData cert_hook_data;
 697         gchar *fingerprint;
 698         size_t n;
 699         unsigned char md[128];
 700         gboolean valid = FALSE;
 701
 702         current_cert = ssl_certificate_new(x509_cert, host, port);
 703
 704         if (current_cert == NULL) {
 705                 debug_print("Buggy certificate !\n");
 706                 return FALSE;
 707         }
 708
 709         current_cert->status = status;
 710         /* fingerprint */
 711         n = sizeof(md);
 712         gnutls_x509_crt_get_fingerprint(x509_cert, GNUTLS_DIG_MD5, md, &n);
 713         fingerprint = readable_fingerprint(md, n);
 714
 715         known_cert = ssl_certificate_find(host, port, fingerprint);
 716
 717         g_free(fingerprint);
 718
 719         if (accept_if_valid)
 720                 valid = ssl_certificate_is_valid(current_cert, status);
 721         else
 722                 valid = FALSE; /* Force check */
 723
 724         if (known_cert == NULL) {
 725                 if (valid) {
 726                         ssl_certificate_save(current_cert);
 727                         ssl_certificate_destroy(current_cert);
 728                         return TRUE;
 729                 }
 730
 731                 cert_hook_data.cert = current_cert;
 732                 cert_hook_data.old_cert = NULL;
 733                 cert_hook_data.expired = FALSE;
 734                 cert_hook_data.accept = FALSE;
 735
 736                 hooks_invoke(SSLCERT_ASK_HOOKLIST, &cert_hook_data);
 737
 738                 if (!cert_hook_data.accept) {
 739                         ssl_certificate_destroy(current_cert);
 740                         return FALSE;
 741                 } else {
 742                         ssl_certificate_save(current_cert);
 743                         ssl_certificate_destroy(current_cert);
 744                         return TRUE;
 745                 }
 746         } else if (!ssl_certificate_compare (current_cert, known_cert)) {
 747                 if (valid) {
 748                         ssl_certificate_save(current_cert);
 749                         ssl_certificate_destroy(current_cert);
 750                         ssl_certificate_destroy(known_cert);
 751                         return TRUE;
 752                 }
 753
 754                 cert_hook_data.cert = current_cert;
 755                 cert_hook_data.old_cert = known_cert;
 756                 cert_hook_data.expired = FALSE;
 757                 cert_hook_data.accept = FALSE;
 758
 759                 hooks_invoke(SSLCERT_ASK_HOOKLIST, &cert_hook_data);
 760
 761                 if (!cert_hook_data.accept) {
 762                         ssl_certificate_destroy(current_cert);
 763                         ssl_certificate_destroy(known_cert);
 764                         return FALSE;
 765                 } else {
 766                         ssl_certificate_save(current_cert);
 767                         ssl_certificate_destroy(current_cert);
 768                         ssl_certificate_destroy(known_cert);
 769                         return TRUE;
 770                 }
 771         } else if (gnutls_x509_crt_get_expiration_time(current_cert->x509_cert) < time(NULL)) {
 772                 gchar *tmp = g_strdup_printf("%s:%d", current_cert->host, current_cert->port);
 773
 774                 if (warned_expired == NULL)
 775                         warned_expired = g_hash_table_new(g_str_hash, g_str_equal);
 776
 777                 if (g_hash_table_lookup(warned_expired, tmp)) {
 778                         g_free(tmp);
 779                         ssl_certificate_destroy(current_cert);
 780                         ssl_certificate_destroy(known_cert);
 781                         return TRUE;
 782                 }
 783
 784                 cert_hook_data.cert = current_cert;
 785                 cert_hook_data.old_cert = NULL;
 786                 cert_hook_data.expired = TRUE;
 787                 cert_hook_data.accept = FALSE;
 788
 789                 hooks_invoke(SSLCERT_ASK_HOOKLIST, &cert_hook_data);
 790
 791                 if (!cert_hook_data.accept) {
 792                         g_free(tmp);
 793                         ssl_certificate_destroy(current_cert);
 794                         ssl_certificate_destroy(known_cert);
 795                         return FALSE;
 796                 } else {
 797                         g_hash_table_insert(warned_expired, tmp, GINT_TO_POINTER(1));
 798                         ssl_certificate_destroy(current_cert);
 799                         ssl_certificate_destroy(known_cert);
 800                         return TRUE;
 801                 }
 802         }
 803
 804         ssl_certificate_destroy(current_cert);
 805         ssl_certificate_destroy(known_cert);
 806         return TRUE;
 807 }
 808
 809 gboolean ssl_certificate_check_chain(gnutls_x509_crt_t *certs, gint chain_len,
 810                                      const gchar *host, gushort port,
 811                                      gboolean accept_if_valid)
 812 {
 813         int ncas = 0;
 814         gnutls_x509_crt_t *cas = NULL;
 815         gboolean result = FALSE;
 816         int i;
 817         gint status;
 818
 819         if (claws_ssl_get_cert_file()) {
 820                 FILE *fp = g_fopen(claws_ssl_get_cert_file(), "rb");
 821                 int r = -errno;
 822
 823                 if (fp) {
 824                         r = gnutls_import_X509_list_fp(fp, GNUTLS_X509_FMT_PEM, &cas, &ncas);
 825                         fclose(fp);
 826                 }
 827
 828                 if (r < 0)
 829                         g_warning("Can't read SSL_CERT_FILE %s: %s\n",
 830                                 claws_ssl_get_cert_file(),
 831                                 gnutls_strerror(r));
 832         } else {
 833                 debug_print("Can't find SSL ca-certificates file\n");
 834         }
 835
 836
 837         gnutls_x509_crt_list_verify (certs,
 838                              chain_len,
 839                              cas, ncas,
 840                              NULL, 0,
 841                              GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT,
 842                              &status);
 843
 844         result = ssl_certificate_check(certs[0], status, host, port,
 845                                         accept_if_valid);
 846
 847         if (result == TRUE) {
 848                 ssl_certificate_save_chain(certs, chain_len, host, port);
 849         }
 850
 851         for (i = 0; i < ncas; i++)
 852                 gnutls_x509_crt_deinit(cas[i]);
 853         free(cas);
 854
 855         return result;
 856 }
 857
 858 gnutls_x509_crt_t ssl_certificate_get_x509_from_pem_file(const gchar *file)
 859 {
 860         gnutls_x509_crt_t x509 = NULL;
 861         if (!file)
 862                 return NULL;
 863
 864         if (is_file_exist(file)) {
 865                 FILE *fp = g_fopen(file, "r");
 866                 if (fp) {
 867                         x509 = gnutls_import_X509_fp(fp, GNUTLS_X509_FMT_PEM);
 868                         fclose(fp);
 869                         return x509;
 870                 } else {
 871                         log_error(LOG_PROTOCOL, _("Cannot open certificate file %s: %s\n"),
 872                                   file, g_strerror(errno));
 873                 }
 874         } else {
 875                 log_error(LOG_PROTOCOL, _("Certificate file %s missing (%s)\n"),
 876                           file, g_strerror(errno));
 877         }
 878         return NULL;
 879 }
 880
 881 gnutls_x509_privkey_t ssl_certificate_get_pkey_from_pem_file(const gchar *file)
 882 {
 883         gnutls_x509_privkey_t key = NULL;
 884         if (!file)
 885                 return NULL;
 886
 887         if (is_file_exist(file)) {
 888                 FILE *fp = g_fopen(file, "r");
 889                 if (fp) {
 890                         key = gnutls_import_key_fp(fp, GNUTLS_X509_FMT_PEM);
 891                         fclose(fp);
 892                         return key;
 893                 } else {
 894                         log_error(LOG_PROTOCOL, _("Cannot open key file %s (%s)\n"),
 895                         file, g_strerror(errno));
 896                 }
 897         } else {
 898                 log_error(LOG_PROTOCOL, _("Key file %s missing (%s)\n"), file,
 899                           g_strerror(errno));
 900         }
 901         return NULL;
 902 }
 903
 904 /* From GnuTLS lib/gnutls_x509.c */
 905 static int
 906 parse_pkcs12 (gnutls_pkcs12_t p12,
 907               const char *password,
 908               gnutls_x509_privkey_t * key,
 909               gnutls_x509_crt_t * cert)
 910 {
 911   gnutls_pkcs12_bag_t bag = NULL;
 912   int index = 0;
 913   int ret;
 914
 915   for (;;)
 916     {
 917       int elements_in_bag;
 918       int i;
 919
 920       ret = gnutls_pkcs12_bag_init (&bag);
 921       if (ret < 0)
 922         {
 923           bag = NULL;
 924           goto done;
 925         }
 926
 927       ret = gnutls_pkcs12_get_bag (p12, index, bag);
 928       if (ret == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE)
 929         break;
 930       if (ret < 0)
 931         {
 932           goto done;
 933         }
 934
 935       ret = gnutls_pkcs12_bag_get_type (bag, 0);
 936       if (ret < 0)
 937         {
 938           goto done;
 939         }
 940
 941       if (ret == GNUTLS_BAG_ENCRYPTED)
 942         {
 943           ret = gnutls_pkcs12_bag_decrypt (bag, password);
 944           if (ret < 0)
 945             {
 946               goto done;
 947             }
 948         }
 949
 950       elements_in_bag = gnutls_pkcs12_bag_get_count (bag);
 951       if (elements_in_bag < 0)
 952         {
 953           goto done;
 954         }
 955
 956       for (i = 0; i < elements_in_bag; i++)
 957         {
 958           int type;
 959           gnutls_datum_t data;
 960
 961           type = gnutls_pkcs12_bag_get_type (bag, i);
 962           if (type < 0)
 963             {
 964               goto done;
 965             }
 966
 967           ret = gnutls_pkcs12_bag_get_data (bag, i, &data);
 968           if (ret < 0)
 969             {
 970               goto done;
 971             }
 972
 973           switch (type)
 974             {
 975             case GNUTLS_BAG_PKCS8_ENCRYPTED_KEY:
 976             case GNUTLS_BAG_PKCS8_KEY:
 977               ret = gnutls_x509_privkey_init (key);
 978               if (ret < 0)
 979                 {
 980                   goto done;
 981                 }
 982
 983               ret = gnutls_x509_privkey_import_pkcs8
 984                 (*key, &data, GNUTLS_X509_FMT_DER, password,
 985                  type == GNUTLS_BAG_PKCS8_KEY ? GNUTLS_PKCS_PLAIN : 0);
 986               if (ret < 0)
 987                 {
 988                   goto done;
 989                 }
 990               break;
 991
 992             case GNUTLS_BAG_CERTIFICATE:
 993               ret = gnutls_x509_crt_init (cert);
 994               if (ret < 0)
 995                 {
 996                   goto done;
 997                 }
 998
 999               ret =
1000                 gnutls_x509_crt_import (*cert, &data, GNUTLS_X509_FMT_DER);
1001               if (ret < 0)
1002                 {
1003                   goto done;
1004                 }
1005               break;
1006
1007             case GNUTLS_BAG_ENCRYPTED:
1008               /* XXX Bother to recurse one level down?  Unlikely to
1009                  use the same password anyway. */
1010             case GNUTLS_BAG_EMPTY:
1011             default:
1012               break;
1013             }
1014         }
1015
1016       index++;
1017       gnutls_pkcs12_bag_deinit (bag);
1018     }
1019
1020   ret = 0;
1021
1022 done:
1023   if (bag)
1024     gnutls_pkcs12_bag_deinit (bag);
1025
1026   return ret;
1027 }
1028 void ssl_certificate_get_x509_and_pkey_from_p12_file(const gchar *file, const gchar *password,
1029                         gnutls_x509_crt_t *x509, gnutls_x509_privkey_t *pkey)
1030 {
1031         gnutls_pkcs12_t p12 = NULL;
1032
1033         int r;
1034
1035         *x509 = NULL;
1036         *pkey = NULL;
1037         if (!file)
1038                 return;
1039
1040         if (is_file_exist(file)) {
1041                 FILE *fp = g_fopen(file, "r");
1042                 if (fp) {
1043                         p12 = gnutls_import_PKCS12_fp(fp, GNUTLS_X509_FMT_DER);
1044                         fclose(fp);
1045                         if (!p12) {
1046                                 log_error(LOG_PROTOCOL, _("Failed to read P12 certificate file %s\n"), file);
1047                         }
1048                 } else {
1049                         log_error(LOG_PROTOCOL, _("Cannot open P12 certificate file %s (%s)\n"),
1050                                   file, g_strerror(errno));
1051                 }
1052         } else {
1053                 log_error(LOG_PROTOCOL, _("P12 Certificate file %s missing (%s)\n"), file,
1054                           g_strerror(errno));
1055         }
1056         if (p12 != NULL) {
1057                 if ((r = parse_pkcs12(p12, password, pkey, x509)) == 0) {
1058                         debug_print("got p12\n");
1059                 } else {
1060                         log_error(LOG_PROTOCOL, "%s\n", gnutls_strerror(r));
1061                 }
1062                 gnutls_pkcs12_deinit(p12);
1063         }
1064 }
1065
1066 gboolean ssl_certificate_check_subject_cn(SSLCertificate *cert)
1067 {
1068         return gnutls_x509_crt_check_hostname(cert->x509_cert, cert->host) != 0;
1069 }
1070
1071 gchar *ssl_certificate_get_subject_cn(SSLCertificate *cert)
1072 {
1073         gchar subject_cn[BUFFSIZE];
1074         size_t n = BUFFSIZE;
1075
1076         if(gnutls_x509_crt_get_dn_by_oid(cert->x509_cert,
1077                 GNUTLS_OID_X520_COMMON_NAME, 0, 0, subject_cn, &n))
1078                 return g_strdup(_("<not in certificate>"));
1079
1080         return g_strdup(subject_cn);
1081 }
1082
1083 #endif /* USE_GNUTLS */