src/common/ssl.c

   1 /*
   2  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2007 Hiroyuki Yamamoto and the Claws Mail team
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  17  *
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #  include "config.h"
  22 #endif
  23
  24 #ifdef USE_GNUTLS
  25 #include "defs.h"
  26
  27 #include <glib.h>
  28 #include <glib/gi18n.h>
  29 #include <errno.h>
  30 #include <pthread.h>
  31 #include <gcrypt.h>
  32 GCRY_THREAD_OPTION_PTHREAD_IMPL;
  33
  34 #include "claws.h"
  35 #include "utils.h"
  36 #include "ssl.h"
  37 #include "ssl_certificate.h"
  38 #include "hooks.h"
  39
  40 #ifdef HAVE_LIBETPAN
  41 #include <libetpan/mailstream_ssl.h>
  42 #endif
  43
  44 #ifdef USE_PTHREAD
  45 #include <pthread.h>
  46 #endif
  47
  48 #ifdef USE_PTHREAD
  49 typedef struct _thread_data {
  50         gnutls_session ssl;
  51         gboolean done;
  52 } thread_data;
  53 #endif
  54
  55 static int gnutls_client_cert_cb(gnutls_session session,
  56                                const gnutls_datum *req_ca_rdn, int nreqs,
  57                                const gnutls_pk_algorithm *sign_algos,
  58                                int sign_algos_length, gnutls_retr_st *st)
  59 {
  60         SSLClientCertHookData hookdata;
  61         SockInfo *sockinfo = (SockInfo *)gnutls_session_get_ptr(session);
  62         gnutls_certificate_type type = gnutls_certificate_type_get(session);
  63         gnutls_x509_crt crt;
  64         gnutls_x509_privkey key;
  65
  66         st->ncerts = 0;
  67
  68         hookdata.account = sockinfo->account;
  69         hookdata.cert_path = NULL;
  70         hookdata.password = NULL;
  71         hookdata.is_smtp = sockinfo->is_smtp;
  72         hooks_invoke(SSLCERT_GET_CLIENT_CERT_HOOKLIST, &hookdata);
  73
  74         if (hookdata.cert_path == NULL)
  75                 return 0;
  76
  77         sockinfo->client_crt = ssl_certificate_get_x509_from_pem_file(hookdata.cert_path);
  78         sockinfo->client_key = ssl_certificate_get_pkey_from_pem_file(hookdata.cert_path);
  79         if (!(sockinfo->client_crt && sockinfo->client_key)) {
  80                 /* try pkcs12 format */
  81                 ssl_certificate_get_x509_and_pkey_from_p12_file(hookdata.cert_path, hookdata.password,
  82                         &crt, &key);
  83                 sockinfo->client_crt = crt;
  84                 sockinfo->client_key = key;
  85         }
  86
  87         if (type == GNUTLS_CRT_X509 && sockinfo->client_crt && sockinfo->client_key) {
  88                 st->ncerts = 1;
  89                 st->type = type;
  90                 st->cert.x509 = &(sockinfo->client_crt);
  91                 st->key.x509 = sockinfo->client_key;
  92                 st->deinit_all = 0;
  93                 return 0;
  94         }
  95         return 0;
  96 }
  97
  98 const gchar *claws_ssl_get_cert_file(void)
  99 {
 100         const char *cert_files[]={
 101                 "/etc/pki/tls/certs/ca-bundle.crt",
 102                 "/etc/certs/ca-bundle.crt",
 103                 "/usr/share/ssl/certs/ca-bundle.crt",
 104                 "/etc/ssl/certs/ca-certificates.crt",
 105                 "/usr/local/ssl/certs/ca-bundle.crt",
 106                 "/etc/apache/ssl.crt/ca-bundle.crt",
 107                 "/usr/share/curl/curl-ca-bundle.crt",
 108                 "/usr/share/curl/curl-ca-bundle.crt",
 109                 "/usr/lib/ssl/cert.pem",
 110                 NULL};
 111         int i;
 112
 113         if (g_getenv("SSL_CERT_FILE"))
 114                 return g_getenv("SSL_CERT_FILE");
 115 #ifndef G_OS_WIN32
 116         for (i = 0; cert_files[i]; i++) {
 117                 if (is_file_exist(cert_files[i]))
 118                         return cert_files[i];
 119         }
 120         return NULL;
 121 #else
 122         return "put_what_s_needed_here";
 123 #endif
 124 }
 125
 126 const gchar *claws_ssl_get_cert_dir(void)
 127 {
 128         const char *cert_dirs[]={
 129                 "/etc/pki/tls/certs",
 130                 "/etc/certs",
 131                 "/usr/share/ssl/certs",
 132                 "/etc/ssl/certs",
 133                 "/usr/local/ssl/certs",
 134                 "/etc/apache/ssl.crt",
 135                 "/usr/share/curl",
 136                 "/usr/lib/ssl/certs",
 137                 NULL};
 138         int i;
 139
 140         if (g_getenv("SSL_CERT_DIR"))
 141                 return g_getenv("SSL_CERT_DIR");
 142 #ifndef G_OS_WIN32
 143         for (i = 0; cert_dirs[i]; i++) {
 144                 if (is_dir_exist(cert_dirs[i]))
 145                         return cert_dirs[i];
 146         }
 147         return NULL;
 148 #else
 149         return "put_what_s_needed_here";
 150 #endif
 151 }
 152
 153 void ssl_init(void)
 154 {
 155         gcry_control (GCRYCTL_SET_THREAD_CBS, &gcry_threads_pthread);
 156 #ifdef HAVE_LIBETPAN
 157         mailstream_gnutls_init_not_required();
 158 #endif
 159         gnutls_global_init();
 160 }
 161
 162 void ssl_done(void)
 163 {
 164         gnutls_global_deinit();
 165 }
 166
 167 #ifdef USE_PTHREAD
 168 static void *SSL_connect_thread(void *data)
 169 {
 170         thread_data *td = (thread_data *)data;
 171         int result = -1;
 172
 173         pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
 174         pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);
 175
 176         do {
 177                 result = gnutls_handshake(td->ssl);
 178         } while (result == GNUTLS_E_AGAIN || result == GNUTLS_E_INTERRUPTED);
 179
 180         td->done = TRUE; /* let the caller thread join() */
 181         return GINT_TO_POINTER(result);
 182 }
 183 #endif
 184
 185 static gint SSL_connect_nb(gnutls_session ssl)
 186 {
 187         int result;
 188 #ifdef USE_PTHREAD
 189         thread_data *td = g_new0(thread_data, 1);
 190         pthread_t pt;
 191         pthread_attr_t pta;
 192         void *res = NULL;
 193         time_t start_time = time(NULL);
 194         gboolean killed = FALSE;
 195
 196         td->ssl  = ssl;
 197         td->done = FALSE;
 198
 199         /* try to create a thread to initialize the SSL connection,
 200          * fallback to blocking method in case of problem
 201          */
 202         if (pthread_attr_init(&pta) != 0 ||
 203             pthread_attr_setdetachstate(&pta, PTHREAD_CREATE_JOINABLE) != 0 ||
 204             pthread_create(&pt, &pta, SSL_connect_thread, td) != 0) {
 205                 do {
 206                         result = gnutls_handshake(td->ssl);
 207                 } while (result == GNUTLS_E_AGAIN || result == GNUTLS_E_INTERRUPTED);
 208                 return result;
 209         }
 210         debug_print("waiting for SSL_connect thread...\n");
 211         while(!td->done) {
 212                 /* don't let the interface freeze while waiting */
 213                 claws_do_idle();
 214                 if (time(NULL) - start_time > 30) {
 215                         pthread_cancel(pt);
 216                         td->done = TRUE;
 217                         killed = TRUE;
 218                 }
 219         }
 220
 221         /* get the thread's return value and clean its resources */
 222         pthread_join(pt, &res);
 223         g_free(td);
 224
 225         if (killed) {
 226                 res = GINT_TO_POINTER(-1);
 227         }
 228         debug_print("SSL_connect thread returned %d\n",
 229                         GPOINTER_TO_INT(res));
 230
 231         return GPOINTER_TO_INT(res);
 232 #else /* USE_PTHREAD */
 233         do {
 234                 result = gnutls_handshake(ssl);
 235         } while (result == GNUTLS_E_AGAIN || result == GNUTLS_E_INTERRUPTED);
 236 #endif
 237 }
 238
 239 gboolean ssl_init_socket(SockInfo *sockinfo)
 240 {
 241         return ssl_init_socket_with_method(sockinfo, SSL_METHOD_SSLv23);
 242 }
 243
 244 gboolean ssl_init_socket_with_method(SockInfo *sockinfo, SSLMethod method)
 245 {
 246         gnutls_session session;
 247         int r;
 248         const int cipher_prio[] = { GNUTLS_CIPHER_AES_128_CBC,
 249                                 GNUTLS_CIPHER_3DES_CBC,
 250                                 GNUTLS_CIPHER_AES_256_CBC,
 251                                 GNUTLS_CIPHER_ARCFOUR_128, 0 };
 252         const int kx_prio[] = { GNUTLS_KX_DHE_RSA,
 253                            GNUTLS_KX_RSA,
 254                            GNUTLS_KX_DHE_DSS, 0 };
 255         const int mac_prio[] = { GNUTLS_MAC_SHA1,
 256                                 GNUTLS_MAC_MD5, 0 };
 257         const int proto_prio[] = { GNUTLS_TLS1,
 258                                   GNUTLS_SSL3, 0 };
 259         const gnutls_datum *raw_cert_list;
 260         unsigned int raw_cert_list_length;
 261         gnutls_x509_crt cert = NULL;
 262         guint status;
 263         gnutls_certificate_credentials_t xcred;
 264
 265         if (gnutls_certificate_allocate_credentials (&xcred) != 0)
 266                 return FALSE;
 267
 268         r = gnutls_init(&session, GNUTLS_CLIENT);
 269         if (session == NULL || r != 0)
 270                 return FALSE;
 271
 272         gnutls_set_default_priority(session);
 273         gnutls_protocol_set_priority (session, proto_prio);
 274         gnutls_cipher_set_priority (session, cipher_prio);
 275         gnutls_kx_set_priority (session, kx_prio);
 276         gnutls_mac_set_priority (session, mac_prio);
 277
 278         gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, xcred);
 279
 280         if (claws_ssl_get_cert_file()) {
 281                 r = gnutls_certificate_set_x509_trust_file(xcred, claws_ssl_get_cert_file(),  GNUTLS_X509_FMT_PEM);
 282                 if (r < 0)
 283                         g_warning("Can't read SSL_CERT_FILE %s: %s\n",
 284                                 claws_ssl_get_cert_file(),
 285                                 gnutls_strerror(r));
 286         } else {
 287                 debug_print("Can't find SSL ca-certificates file\n");
 288         }
 289         gnutls_certificate_set_verify_flags (xcred, GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT);
 290
 291         gnutls_transport_set_ptr(session, (gnutls_transport_ptr) sockinfo->sock);
 292         gnutls_session_set_ptr(session, sockinfo);
 293         gnutls_certificate_client_set_retrieve_function(xcred, gnutls_client_cert_cb);
 294
 295         gnutls_dh_set_prime_bits(session, 512);
 296
 297         if ((r = SSL_connect_nb(session)) < 0) {
 298                 g_warning("SSL connection failed (%s)", gnutls_strerror(r));
 299                 gnutls_certificate_free_credentials(xcred);
 300                 gnutls_deinit(session);
 301                 return FALSE;
 302         }
 303
 304         /* Get server's certificate (note: beware of dynamic allocation) */
 305         raw_cert_list = gnutls_certificate_get_peers(session, &raw_cert_list_length);
 306
 307         if (!raw_cert_list
 308         ||  gnutls_certificate_type_get(session) != GNUTLS_CRT_X509
 309         ||  (r = gnutls_x509_crt_init(&cert)) < 0
 310         ||  (r = gnutls_x509_crt_import(cert, &raw_cert_list[0], GNUTLS_X509_FMT_DER)) < 0) {
 311                 g_warning("cert get failure: %d %s\n", r, gnutls_strerror(r));
 312                 gnutls_certificate_free_credentials(xcred);
 313                 gnutls_deinit(session);
 314                 return FALSE;
 315         }
 316
 317         r = gnutls_certificate_verify_peers2(session, &status);
 318
 319         if (!ssl_certificate_check(cert, status, sockinfo->canonical_name, sockinfo->hostname, sockinfo->port)) {
 320                 gnutls_x509_crt_deinit(cert);
 321                 gnutls_certificate_free_credentials(xcred);
 322                 gnutls_deinit(session);
 323                 return FALSE;
 324         }
 325
 326         gnutls_x509_crt_deinit(cert);
 327
 328         sockinfo->ssl = session;
 329         sockinfo->xcred = xcred;
 330         return TRUE;
 331 }
 332
 333 void ssl_done_socket(SockInfo *sockinfo)
 334 {
 335         if (sockinfo && sockinfo->ssl) {
 336                 gnutls_certificate_free_credentials(sockinfo->xcred);
 337                 gnutls_deinit(sockinfo->ssl);
 338                 if (sockinfo->client_crt)
 339                         gnutls_x509_crt_deinit(sockinfo->client_crt);
 340                 if (sockinfo->client_key)
 341                         gnutls_x509_privkey_deinit(sockinfo->client_key);
 342                 sockinfo->client_key = NULL;
 343                 sockinfo->client_crt = NULL;
 344                 sockinfo->ssl = NULL;
 345         }
 346 }
 347
 348 #endif /* USE_GNUTLS */