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1 /*
2  * ngIRCd -- The Next Generation IRC Daemon
3  * Copyright (c)2005-2008 Florian Westphal (fw@strlen.de).
4  * Copyright (c)2008-2014 Alexander Barton (alex@barton.de) and Contributors.
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 2 of the License, or
9  * (at your option) any later version.
10  * Please read the file COPYING, README and AUTHORS for more information.
11  */
12
13 #include "portab.h"
14
15 /**
16  * @file
17  * SSL wrapper functions
18  */
19
20 #include "conf-ssl.h"
21
22 #ifdef SSL_SUPPORT
23
24 #include "io.h"
25 #include <assert.h>
26 #include <stdio.h>
27 #include <string.h>
28 #include <stdlib.h>
29 #include <errno.h>
30
31 #define CONN_MODULE
32 #include "conn.h"
33 #include "conf.h"
34 #include "conn-func.h"
35 #include "conn-ssl.h"
36 #include "log.h"
37
38 #include "defines.h"
39
40 extern struct SSLOptions Conf_SSLOptions;
41
42 #ifdef HAVE_LIBSSL
43 #include <openssl/err.h>
44 #include <openssl/rand.h>
45 #include <openssl/dh.h>
46 #include <openssl/x509v3.h>
47
48 #define MAX_CERT_CHAIN_LENGTH   10      /* XXX: do not hardcode */
49
50 static SSL_CTX * ssl_ctx;
51 static DH *dh_params;
52
53 static bool ConnSSL_LoadServerKey_openssl PARAMS(( SSL_CTX *c ));
54 static bool ConnSSL_SetVerifyProperties_openssl PARAMS((SSL_CTX * c));
55 #endif
56
57 #ifdef HAVE_LIBGNUTLS
58 #include <sys/types.h>
59 #include <sys/stat.h>
60 #include <fcntl.h>
61 #include <unistd.h>
62 #include <gnutls/x509.h>
63
64 #define DH_BITS 2048
65 #define DH_BITS_MIN 1024
66
67 #define MAX_HASH_SIZE   64      /* from gnutls-int.h */
68
69 typedef struct {
70         int refcnt;
71         gnutls_certificate_credentials_t x509_cred;
72         gnutls_dh_params_t dh_params;
73 } x509_cred_slot;
74
75 static array x509_creds = INIT_ARRAY;
76 static size_t x509_cred_idx;
77
78 static gnutls_dh_params_t dh_params;
79 static gnutls_priority_t priorities_cache = NULL;
80 static bool ConnSSL_LoadServerKey_gnutls PARAMS(( void ));
81 static bool ConnSSL_SetVerifyProperties_gnutls PARAMS((void));
82 #endif
83
84 #define SHA256_STRING_LEN       (32 * 2 + 1)
85
86 static bool ConnSSL_Init_SSL PARAMS(( CONNECTION *c ));
87 static int ConnectAccept PARAMS(( CONNECTION *c, bool connect ));
88 static int ConnSSL_HandleError PARAMS(( CONNECTION *c, const int code, const char *fname ));
89
90 #ifdef HAVE_LIBGNUTLS
91 static char * openreadclose(const char *name, size_t *len)
92 {
93         char *buf = NULL;
94         struct stat s;
95         ssize_t br;
96         int fd = open(name, O_RDONLY);
97         if (fd < 0) {
98                 Log(LOG_ERR, "Could not open %s: %s", name, strerror(errno));
99                 return NULL;
100         }
101         if (fstat(fd, &s)) {
102                 Log(LOG_ERR, "Could not fstat %s: %s", name, strerror(errno));
103                 goto out;
104         }
105         if (!S_ISREG(s.st_mode)) {
106                 Log(LOG_ERR, "%s: Not a regular file", name);
107                 goto out;
108         }
109         if (s.st_size <= 0) {
110                 Log(LOG_ERR, "%s: invalid file length (size %ld <= 0)", name, (long) s.st_size);
111                 goto out;
112         }
113         buf = malloc(s.st_size);
114         if (!buf) {
115                 Log(LOG_ERR, "Could not malloc %lu bytes for file %s: %s", s.st_size, name, strerror(errno));
116                 goto out;
117         }
118         br = read(fd, buf, s.st_size);
119         if (br != (ssize_t)s.st_size) {
120                 Log(LOG_ERR, "Could not read file %s: read returned %ld, expected %ld: %s",
121                         name, (long) br, (long) s.st_size, br == -1 ? strerror(errno):"short read?!");
122                 memset(buf, 0, s.st_size);
123                 free(buf);
124                 buf = NULL;
125         } else {
126                 *len = br;
127         }
128 out:
129         close(fd);
130         return buf;
131 }
132 #endif
133
134
135 #ifdef HAVE_LIBSSL
136 /**
137  * Log OpenSSL error message.
138  *
139  * @param level The log level
140  * @param msg The error message.
141  * @param info Additional information text or NULL.
142  */
143 static void
144 LogOpenSSL_CertInfo(int level, X509 * cert, const char *msg)
145 {
146         BIO *mem;
147         char *memptr;
148         long len;
149
150         assert(cert);
151         assert(msg);
152
153         if (!cert)
154                 return;
155         mem = BIO_new(BIO_s_mem());
156         if (!mem)
157                 return;
158         X509_NAME_print_ex(mem, X509_get_subject_name(cert), 0,
159                            XN_FLAG_ONELINE);
160         X509_NAME_print_ex(mem, X509_get_issuer_name(cert), 2, XN_FLAG_ONELINE);
161         if (BIO_write(mem, "", 1) == 1) {
162                 len = BIO_get_mem_data(mem, &memptr);
163                 if (memptr && len > 0)
164                         Log(level, "%s: \"%s\".", msg, memptr);
165         }
166         (void)BIO_set_close(mem, BIO_CLOSE);
167         BIO_free(mem);
168 }
169
170 static void
171 LogOpenSSLError(const char *error, const char *info)
172 {
173         unsigned long err = ERR_get_error();
174         char * errmsg = err
175                 ? ERR_error_string(err, NULL)
176                 : "Unable to determine error";
177
178         assert(error != NULL);
179
180         if (info)
181                 Log(LOG_ERR, "%s: %s (%s)", error, info, errmsg);
182         else
183                 Log(LOG_ERR, "%s: %s", error, errmsg);
184 }
185
186
187 static int
188 pem_passwd_cb(char *buf, int size, int rwflag, void *password)
189 {
190         array *pass = password;
191         int passlen;
192
193         (void)rwflag;           /* rwflag is unused if DEBUG is not set. */
194         assert(rwflag == 0);    /* 0 -> callback used for decryption.
195                                  * See SSL_CTX_set_default_passwd_cb(3) */
196
197         passlen = (int) array_bytes(pass);
198
199         LogDebug("pem_passwd_cb buf size %d, array size %d", size, passlen);
200         assert(passlen >= 0);
201         if (passlen <= 0) {
202                 Log(LOG_ERR, "PEM password required but not set [in pem_passwd_cb()]!");
203                 return 0;
204         }
205         size = passlen > size ? size : passlen;
206         memcpy(buf, (char *)(array_start(pass)), size);
207         return size;
208 }
209
210
211 static int
212 Verify_openssl(int preverify_ok, X509_STORE_CTX * ctx)
213 {
214 #ifdef DEBUG
215         if (!preverify_ok) {
216                 int err = X509_STORE_CTX_get_error(ctx);
217                 LogDebug("Certificate validation failed: %s",
218                          X509_verify_cert_error_string(err));
219         }
220 #else
221         (void)preverify_ok;
222         (void)ctx;
223 #endif
224
225         /* Always(!) return success as we have to deal with invalid
226          * (self-signed, expired, ...) client certificates and with invalid
227          * server certificates when "SSLVerify" is disabled, which we don't
228          * know at this stage. Therefore we postpone this check, it will be
229          * (and has to be!) handled in cb_connserver_login_ssl(). */
230         return 1;
231 }
232 #endif
233
234
235 static bool
236 Load_DH_params(void)
237 {
238 #ifdef HAVE_LIBSSL
239         FILE *fp;
240         bool ret = true;
241
242         if (!Conf_SSLOptions.DHFile) {
243                 Log(LOG_NOTICE, "Configuration option \"DHFile\" not set!");
244                 return false;
245         }
246         fp = fopen(Conf_SSLOptions.DHFile, "r");
247         if (!fp) {
248                 Log(LOG_ERR, "%s: %s", Conf_SSLOptions.DHFile, strerror(errno));
249                 return false;
250         }
251         dh_params = PEM_read_DHparams(fp, NULL, NULL, NULL);
252         if (!dh_params) {
253                 Log(LOG_ERR, "%s: Failed to read SSL DH parameters!",
254                     Conf_SSLOptions.DHFile);
255                 ret = false;
256         }
257         fclose(fp);
258         return ret;
259 #endif
260 #ifdef HAVE_LIBGNUTLS
261         bool need_dhgenerate = true;
262         int err;
263         gnutls_dh_params_t tmp_dh_params;
264
265         err = gnutls_dh_params_init(&tmp_dh_params);
266         if (err < 0) {
267                 Log(LOG_ERR, "Failed to initialize SSL DH parameters: %s",
268                     gnutls_strerror(err));
269                 return false;
270         }
271         if (Conf_SSLOptions.DHFile) {
272                 gnutls_datum_t dhparms;
273                 size_t size;
274                 dhparms.data = (unsigned char *) openreadclose(Conf_SSLOptions.DHFile, &size);
275                 if (dhparms.data) {
276                         dhparms.size = size;
277                         err = gnutls_dh_params_import_pkcs3(tmp_dh_params, &dhparms, GNUTLS_X509_FMT_PEM);
278                         if (err == 0)
279                                 need_dhgenerate = false;
280                         else
281                                 Log(LOG_ERR,
282                                     "Failed to initialize SSL DH parameters: %s",
283                                     gnutls_strerror(err));
284
285                         memset(dhparms.data, 0, size);
286                         free(dhparms.data);
287                 }
288         }
289         if (need_dhgenerate) {
290                 Log(LOG_WARNING,
291                     "DHFile not set, generating %u bit DH parameters. This may take a while ...",
292                     DH_BITS);
293                 err = gnutls_dh_params_generate2(tmp_dh_params, DH_BITS);
294                 if (err < 0) {
295                         Log(LOG_ERR, "Failed to generate SSL DH parameters: %s",
296                             gnutls_strerror(err));
297                         return false;
298                 }
299         }
300         dh_params = tmp_dh_params;
301         return true;
302 #endif
303 }
304
305
306 void ConnSSL_Free(CONNECTION *c)
307 {
308 #ifdef HAVE_LIBSSL
309         SSL *ssl = c->ssl_state.ssl;
310         if (ssl) {
311                 SSL_shutdown(ssl);
312                 SSL_free(ssl);
313                 c->ssl_state.ssl = NULL;
314                 if (c->ssl_state.fingerprint) {
315                         free(c->ssl_state.fingerprint);
316                         c->ssl_state.fingerprint = NULL;
317                 }
318         }
319 #endif
320 #ifdef HAVE_LIBGNUTLS
321         gnutls_session_t sess = c->ssl_state.gnutls_session;
322         if (Conn_OPTION_ISSET(c, CONN_SSL)) {
323                 gnutls_bye(sess, GNUTLS_SHUT_RDWR);
324                 gnutls_deinit(sess);
325         }
326         x509_cred_slot *slot = array_get(&x509_creds, sizeof(x509_cred_slot), c->ssl_state.x509_cred_idx);
327         assert(slot != NULL);
328         assert(slot->refcnt > 0);
329         assert(slot->x509_cred != NULL);
330         slot->refcnt--;
331         if ((c->ssl_state.x509_cred_idx != x509_cred_idx) && (slot->refcnt <= 0)) {
332                 LogDebug("Discarding X509 certificate credentials from slot %zd.",
333                          c->ssl_state.x509_cred_idx);
334                 gnutls_certificate_free_keys(slot->x509_cred);
335                 gnutls_certificate_free_credentials(slot->x509_cred);
336                 slot->x509_cred = NULL;
337                 gnutls_dh_params_deinit(slot->dh_params);
338                 slot->dh_params = NULL;
339                 slot->refcnt = 0;
340         }
341 #endif
342         assert(Conn_OPTION_ISSET(c, CONN_SSL));
343         /* can't just set bitmask to 0 -- there are other, non-ssl related flags, e.g. CONN_ZIP. */
344         Conn_OPTION_DEL(c, CONN_SSL_FLAGS_ALL);
345 }
346
347
348 bool
349 ConnSSL_InitLibrary( void )
350 {
351         if (!Conf_SSLInUse()) {
352                 LogDebug("SSL not in use, skipping initialization.");
353                 return true;
354         }
355
356 #ifdef HAVE_LIBSSL
357         SSL_CTX *newctx;
358
359 #if OPENSSL_API_COMPAT < 0x10100000L
360         if (!ssl_ctx) {
361                 SSL_library_init();
362                 SSL_load_error_strings();
363         }
364 #endif
365
366         if (!RAND_status()) {
367                 Log(LOG_ERR, "OpenSSL PRNG not seeded: /dev/urandom missing?");
368                 /*
369                  * it is probably best to fail and let the user install EGD or
370                  * a similar program if no kernel random device is available.
371                  * According to OpenSSL RAND_egd(3): "The automatic query of
372                  * /var/run/egd-pool et al was added in OpenSSL 0.9.7";
373                  * so it makes little sense to deal with PRNGD seeding ourselves.
374                  */
375                 array_free(&Conf_SSLOptions.ListenPorts);
376                 return false;
377         }
378
379         newctx = SSL_CTX_new(SSLv23_method());
380         if (!newctx) {
381                 LogOpenSSLError("Failed to create SSL context", NULL);
382                 array_free(&Conf_SSLOptions.ListenPorts);
383                 return false;
384         }
385
386         if (!ConnSSL_LoadServerKey_openssl(newctx)) {
387                 /* Failed to read new key but an old ssl context
388                  * already exists -> reuse old context */
389                 if (ssl_ctx) {
390                         SSL_CTX_free(newctx);
391                         Log(LOG_WARNING,
392                         "Re-Initializing of SSL failed, using old keys!");
393                         return true;
394                 }
395                 /* No preexisting old context -> error. */
396                 goto out;
397         }
398
399         if (SSL_CTX_set_cipher_list(newctx, Conf_SSLOptions.CipherList) == 0) {
400                 Log(LOG_ERR, "Failed to apply OpenSSL cipher list \"%s\"!",
401                     Conf_SSLOptions.CipherList);
402                 goto out;
403         }
404
405         SSL_CTX_set_session_id_context(newctx, (unsigned char *)"ngircd", 6);
406         if (!ConnSSL_SetVerifyProperties_openssl(newctx))
407                 goto out;
408         SSL_CTX_set_options(newctx,
409                             SSL_OP_SINGLE_DH_USE | SSL_OP_NO_SSLv2 |
410                             SSL_OP_NO_SSLv3 | SSL_OP_NO_TLSv1 | SSL_OP_NO_TLSv1_1 |
411                             SSL_OP_NO_COMPRESSION);
412         SSL_CTX_set_mode(newctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
413         SSL_CTX_free(ssl_ctx);
414         ssl_ctx = newctx;
415         Log(LOG_INFO, "%s initialized.", OpenSSL_version(OPENSSL_VERSION));
416         return true;
417 out:
418         SSL_CTX_free(newctx);
419         array_free(&Conf_SSLOptions.ListenPorts);
420         return false;
421 #endif
422 #ifdef HAVE_LIBGNUTLS
423         int err;
424         static bool initialized;
425
426         if (!initialized) {
427                 err = gnutls_global_init();
428                 if (err) {
429                         Log(LOG_ERR, "Failed to initialize GnuTLS: %s",
430                             gnutls_strerror(err));
431                         goto out;
432                 }
433         }
434
435         if (!ConnSSL_LoadServerKey_gnutls())
436                 goto out;
437
438         if (priorities_cache != NULL) {
439                 gnutls_priority_deinit(priorities_cache);
440         }
441         if (gnutls_priority_init(&priorities_cache, Conf_SSLOptions.CipherList,
442                                  NULL) != GNUTLS_E_SUCCESS) {
443                 Log(LOG_ERR,
444                     "Failed to apply GnuTLS cipher list \"%s\"!",
445                     Conf_SSLOptions.CipherList);
446                 goto out;
447         }
448
449         if (!ConnSSL_SetVerifyProperties_gnutls())
450                 goto out;
451
452         Log(LOG_INFO, "GnuTLS %s initialized.", gnutls_check_version(NULL));
453         initialized = true;
454         return true;
455 out:
456         array_free(&Conf_SSLOptions.ListenPorts);
457         return false;
458 #endif
459 }
460
461
462 #ifdef HAVE_LIBGNUTLS
463 static bool
464 ConnSSL_SetVerifyProperties_gnutls(void)
465 {
466         int err;
467
468         if (!Conf_SSLOptions.CAFile)
469                 return true;
470
471         x509_cred_slot *slot = array_get(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
472         gnutls_certificate_credentials_t x509_cred = slot->x509_cred;
473
474         err = gnutls_certificate_set_x509_trust_file(x509_cred,
475                                                      Conf_SSLOptions.CAFile,
476                                                      GNUTLS_X509_FMT_PEM);
477         if (err < 0) {
478                 Log(LOG_ERR, "Failed to load x509 trust file %s: %s",
479                     Conf_SSLOptions.CAFile, gnutls_strerror(err));
480                 return false;
481         }
482         if (Conf_SSLOptions.CRLFile) {
483                 err =
484                     gnutls_certificate_set_x509_crl_file(x509_cred,
485                                                          Conf_SSLOptions.CRLFile,
486                                                          GNUTLS_X509_FMT_PEM);
487                 if (err < 0) {
488                         Log(LOG_ERR, "Failed to load x509 crl file %s: %s",
489                             Conf_SSLOptions.CRLFile, gnutls_strerror(err));
490                         return false;
491                 }
492         }
493         return true;
494 }
495
496
497 static bool
498 ConnSSL_LoadServerKey_gnutls(void)
499 {
500         int err;
501         const char *cert_file;
502
503         x509_cred_slot *slot = NULL;
504         gnutls_certificate_credentials_t x509_cred;
505
506         err = gnutls_certificate_allocate_credentials(&x509_cred);
507         if (err < 0) {
508                 Log(LOG_ERR, "Failed to allocate certificate credentials: %s",
509                     gnutls_strerror(err));
510                 return false;
511         }
512
513         if (array_bytes(&Conf_SSLOptions.KeyFilePassword))
514                 Log(LOG_WARNING,
515                     "Ignoring SSL \"KeyFilePassword\": Not supported by GnuTLS.");
516
517         if (!Load_DH_params())
518                 return false;
519
520         gnutls_certificate_set_dh_params(x509_cred, dh_params);
521
522         cert_file = Conf_SSLOptions.CertFile ?
523                         Conf_SSLOptions.CertFile : Conf_SSLOptions.KeyFile;
524         if (Conf_SSLOptions.KeyFile) {
525                 err = gnutls_certificate_set_x509_key_file(x509_cred, cert_file,
526                                                            Conf_SSLOptions.KeyFile,
527                                                            GNUTLS_X509_FMT_PEM);
528                 if (err < 0) {
529                         Log(LOG_ERR,
530                             "Failed to set certificate key file (cert %s, key %s): %s",
531                             cert_file,
532                             Conf_SSLOptions.KeyFile ? Conf_SSLOptions.KeyFile : "(NULL)",
533                             gnutls_strerror(err));
534                         return false;
535                 }
536         }
537
538         /* Free currently active x509 context (if any) unless it is still in use */
539         slot = array_get(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
540         if ((slot != NULL) && (slot->refcnt <= 0) && (slot->x509_cred != NULL)) {
541                 LogDebug("Discarding X509 certificate credentials from slot %zd.",
542                          x509_cred_idx);
543                 gnutls_certificate_free_keys(slot->x509_cred);
544                 gnutls_certificate_free_credentials(slot->x509_cred);
545                 slot->x509_cred = NULL;
546                 gnutls_dh_params_deinit(slot->dh_params);
547                 slot->dh_params = NULL;
548                 slot->refcnt = 0;
549         }
550
551         /* Find free slot */
552         x509_cred_idx = (size_t) -1;
553         size_t i;
554         for (slot = array_start(&x509_creds), i = 0;
555              i < array_length(&x509_creds, sizeof(x509_cred_slot));
556              slot++, i++) {
557                 if (slot->refcnt <= 0) {
558                         x509_cred_idx = i;
559                         break;
560                 }
561         }
562         /* ... allocate new slot otherwise. */
563         if (x509_cred_idx == (size_t) -1) {
564                 x509_cred_idx = array_length(&x509_creds, sizeof(x509_cred_slot));
565                 slot = array_alloc(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
566                 if (slot == NULL) {
567                         Log(LOG_ERR, "Failed to allocate new slot for certificate credentials");
568                         return false;
569                 }
570         }
571         Log(LOG_INFO, "Storing new X509 certificate credentials in slot %zd.", x509_cred_idx);
572         slot->x509_cred = x509_cred;
573         slot->refcnt = 0;
574
575         return true;
576 }
577 #endif
578
579
580 #ifdef HAVE_LIBSSL
581 static bool
582 ConnSSL_LoadServerKey_openssl(SSL_CTX *ctx)
583 {
584         char *cert_key;
585
586         assert(ctx);
587         SSL_CTX_set_default_passwd_cb(ctx, pem_passwd_cb);
588         SSL_CTX_set_default_passwd_cb_userdata(ctx, &Conf_SSLOptions.KeyFilePassword);
589
590         if (!Conf_SSLOptions.KeyFile)
591                 return true;
592
593         if (SSL_CTX_use_PrivateKey_file(ctx, Conf_SSLOptions.KeyFile, SSL_FILETYPE_PEM) != 1) {
594                 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
595                 LogOpenSSLError("Failed to add private key", Conf_SSLOptions.KeyFile);
596                 return false;
597         }
598
599         cert_key = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
600         if (SSL_CTX_use_certificate_chain_file(ctx, cert_key) != 1) {
601                 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
602                 LogOpenSSLError("Failed to load certificate chain", cert_key);
603                 return false;
604         }
605
606         array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
607
608         if (!SSL_CTX_check_private_key(ctx)) {
609                 LogOpenSSLError("Server private key does not match certificate", NULL);
610                 return false;
611         }
612         if (Load_DH_params()) {
613                 if (SSL_CTX_set_tmp_dh(ctx, dh_params) != 1)
614                         LogOpenSSLError("Error setting DH parameters", Conf_SSLOptions.DHFile);
615                 /* don't return false here: the non-DH modes will still work */
616                 DH_free(dh_params);
617                 dh_params = NULL;
618         }
619         return true;
620 }
621
622
623 static bool
624 ConnSSL_SetVerifyProperties_openssl(SSL_CTX * ctx)
625 {
626         X509_STORE *store = NULL;
627         X509_LOOKUP *lookup;
628         bool ret = false;
629
630         if (!Conf_SSLOptions.CAFile)
631                 return true;
632
633         if (SSL_CTX_load_verify_locations(ctx, Conf_SSLOptions.CAFile, NULL) !=
634             1) {
635                 LogOpenSSLError("SSL_CTX_load_verify_locations", NULL);
636                 goto out;
637         }
638
639         if (Conf_SSLOptions.CRLFile) {
640                 X509_VERIFY_PARAM *param = X509_VERIFY_PARAM_new();
641                 X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_CRL_CHECK);
642                 SSL_CTX_set1_param(ctx, param);
643
644                 store = SSL_CTX_get_cert_store(ctx);
645                 assert(store);
646                 lookup = X509_STORE_add_lookup(store, X509_LOOKUP_file());
647                 if (!lookup) {
648                         LogOpenSSLError("X509_STORE_add_lookup",
649                                         Conf_SSLOptions.CRLFile);
650                         goto out;
651                 }
652
653                 if (X509_load_crl_file
654                     (lookup, Conf_SSLOptions.CRLFile, X509_FILETYPE_PEM) != 1) {
655                         LogOpenSSLError("X509_load_crl_file",
656                                         Conf_SSLOptions.CRLFile);
657                         goto out;
658                 }
659         }
660
661         SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER|SSL_VERIFY_CLIENT_ONCE,
662                            Verify_openssl);
663         SSL_CTX_set_verify_depth(ctx, MAX_CERT_CHAIN_LENGTH);
664         ret = true;
665 out:
666         if (Conf_SSLOptions.CRLFile)
667                 free(Conf_SSLOptions.CRLFile);
668         Conf_SSLOptions.CRLFile = NULL;
669         return ret;
670 }
671
672
673 #endif
674 static bool
675 ConnSSL_Init_SSL(CONNECTION *c)
676 {
677         int ret;
678
679         LogDebug("Initializing SSL ...");
680         assert(c != NULL);
681
682 #ifdef HAVE_LIBSSL
683         if (!ssl_ctx) {
684                 Log(LOG_ERR,
685                     "Can't initialize SSL context, OpenSSL initialization failed at startup!");
686                 return false;
687         }
688         assert(c->ssl_state.ssl == NULL);
689         assert(c->ssl_state.fingerprint == NULL);
690
691         c->ssl_state.ssl = SSL_new(ssl_ctx);
692         if (!c->ssl_state.ssl) {
693                 LogOpenSSLError("Failed to create SSL structure", NULL);
694                 return false;
695         }
696         Conn_OPTION_ADD(c, CONN_SSL);
697
698         ret = SSL_set_fd(c->ssl_state.ssl, c->sock);
699         if (ret != 1) {
700                 LogOpenSSLError("Failed to set SSL file descriptor", NULL);
701                 ConnSSL_Free(c);
702                 return false;
703         }
704 #endif
705 #ifdef HAVE_LIBGNUTLS
706         Conn_OPTION_ADD(c, CONN_SSL);
707         ret = gnutls_priority_set(c->ssl_state.gnutls_session, priorities_cache);
708         if (ret != GNUTLS_E_SUCCESS) {
709                 Log(LOG_ERR, "Failed to set GnuTLS session priorities: %s",
710                     gnutls_strerror(ret));
711                 ConnSSL_Free(c);
712                 return false;
713         }
714         /*
715          * The intermediate (long) cast is here to avoid a warning like:
716          * "cast to pointer from integer of different size" on 64-bit platforms.
717          * There doesn't seem to be an alternate GNUTLS API we could use instead, see e.g.
718          * http://www.mail-archive.com/help-gnutls@gnu.org/msg00286.html
719          */
720         gnutls_transport_set_ptr(c->ssl_state.gnutls_session,
721                                  (gnutls_transport_ptr_t) (long) c->sock);
722         gnutls_certificate_server_set_request(c->ssl_state.gnutls_session,
723                                               GNUTLS_CERT_REQUEST);
724
725         LogDebug("Using X509 credentials from slot %zd.", x509_cred_idx);
726         c->ssl_state.x509_cred_idx = x509_cred_idx;
727         x509_cred_slot *slot = array_get(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
728         slot->refcnt++;
729         ret = gnutls_credentials_set(c->ssl_state.gnutls_session,
730                                      GNUTLS_CRD_CERTIFICATE, slot->x509_cred);
731         if (ret != 0) {
732                 Log(LOG_ERR, "Failed to set SSL credentials: %s",
733                     gnutls_strerror(ret));
734                 ConnSSL_Free(c);
735                 return false;
736         }
737         gnutls_dh_set_prime_bits(c->ssl_state.gnutls_session, DH_BITS_MIN);
738 #endif
739         return true;
740 }
741
742
743 bool
744 ConnSSL_PrepareConnect(CONNECTION * c, CONF_SERVER * s)
745 {
746         bool ret;
747 #ifdef HAVE_LIBGNUTLS
748         int err;
749
750         (void)s;
751         err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_CLIENT);
752         if (err) {
753                 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
754                     gnutls_strerror(err));
755                 return false;
756         }
757 #endif
758         ret = ConnSSL_Init_SSL(c);
759         if (!ret)
760                 return false;
761         Conn_OPTION_ADD(c, CONN_SSL_CONNECT);
762
763 #ifdef HAVE_LIBSSL
764         assert(c->ssl_state.ssl);
765
766         X509_VERIFY_PARAM *param = SSL_get0_param(c->ssl_state.ssl);
767         X509_VERIFY_PARAM_set_hostflags(param, X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS);
768         int err = X509_VERIFY_PARAM_set1_host(param, s->host, 0);
769         if (err != 1) {
770                 Log(LOG_ERR,
771                     "Cannot set up hostname verification for '%s': %u",
772                     s->host, err);
773                 return false;
774         }
775
776         if (s->SSLVerify)
777                 SSL_set_verify(c->ssl_state.ssl, SSL_VERIFY_PEER,
778                                Verify_openssl);
779         else
780                 SSL_set_verify(c->ssl_state.ssl, SSL_VERIFY_NONE, NULL);
781 #endif
782
783         return true;
784 }
785
786
787 /**
788  * Check and handle error return codes after failed calls to SSL functions.
789  *
790  * OpenSSL:
791  * SSL_connect(), SSL_accept(), SSL_do_handshake(), SSL_read(), SSL_peek(), or
792  * SSL_write() on ssl.
793  *
794  * GnuTLS:
795  * gnutlsssl_read(), gnutls_write() or gnutls_handshake().
796  *
797  * @param c The connection handle.
798  * @prarm code The return code.
799  * @param fname The name of the function in which the error occurred.
800  * @return -1 on fatal errors, 0 if we can try again later.
801  */
802 static int
803 ConnSSL_HandleError(CONNECTION * c, const int code, const char *fname)
804 {
805 #ifdef HAVE_LIBSSL
806         int ret = SSL_ERROR_SYSCALL;
807         unsigned long sslerr;
808         int real_errno = errno;
809
810         ret = SSL_get_error(c->ssl_state.ssl, code);
811
812         switch (ret) {
813         case SSL_ERROR_WANT_READ:
814                 io_event_del(c->sock, IO_WANTWRITE);
815                 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
816                 return 0;       /* try again later */
817         case SSL_ERROR_WANT_WRITE:
818                 io_event_del(c->sock, IO_WANTREAD);
819                 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE); /* fall through */
820         case SSL_ERROR_NONE:
821                 return 0;       /* try again later */
822         case SSL_ERROR_ZERO_RETURN:
823                 LogDebug("SSL connection shut down normally.");
824                 break;
825         case SSL_ERROR_SYSCALL:
826                 /* SSL_ERROR_WANT_CONNECT, SSL_ERROR_WANT_ACCEPT,
827                  * and SSL_ERROR_WANT_X509_LOOKUP */
828                 sslerr = ERR_get_error();
829                 if (sslerr) {
830                         Log(LOG_ERR, "SSL error: %s [in %s()]!",
831                             ERR_error_string(sslerr, NULL), fname);
832                 } else {
833                         switch (code) { /* EOF that violated protocol */
834                         case 0:
835                                 Log(LOG_ERR,
836                                     "SSL error, client disconnected [in %s()]!",
837                                     fname);
838                                 break;
839                         case -1:
840                                 /* Low level socket I/O error, check errno. But
841                                  * we don't need to log this here, the generic
842                                  * connection layer will take care of it. */
843                                 LogDebug("SSL error: %s [in %s()]!",
844                                          strerror(real_errno), fname);
845                         }
846                 }
847                 break;
848         case SSL_ERROR_SSL:
849                 LogOpenSSLError("SSL protocol error", fname);
850                 break;
851         default:
852                 Log(LOG_ERR, "Unknown SSL error %d [in %s()]!", ret, fname);
853         }
854         ConnSSL_Free(c);
855         return -1;
856 #endif
857 #ifdef HAVE_LIBGNUTLS
858         switch (code) {
859         case GNUTLS_E_AGAIN:
860         case GNUTLS_E_INTERRUPTED:
861                 if (gnutls_record_get_direction(c->ssl_state.gnutls_session)) {
862                         Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE);
863                         io_event_del(c->sock, IO_WANTREAD);
864                 } else {
865                         Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
866                         io_event_del(c->sock, IO_WANTWRITE);
867                 }
868                 break;
869         default:
870                 assert(code < 0);
871                 if (gnutls_error_is_fatal(code)) {
872                         /* We don't need to log this here, the generic
873                          * connection layer will take care of it. */
874                         LogDebug("SSL error: %s [%s].",
875                                  gnutls_strerror(code), fname);
876                         ConnSSL_Free(c);
877                         return -1;
878                 }
879         }
880         return 0;
881 #endif
882 }
883
884
885 #ifdef HAVE_LIBGNUTLS
886 static void *
887 LogMalloc(size_t s)
888 {
889         void *mem = malloc(s);
890         if (!mem)
891                 Log(LOG_ERR, "Out of memory: Could not allocate %lu byte",
892                     (unsigned long)s);
893         return mem;
894 }
895
896
897 static void
898 LogGnuTLS_CertInfo(int level, gnutls_x509_crt_t cert, const char *msg)
899 {
900         char *dn, *issuer_dn;
901         size_t size = 0;
902         int err = gnutls_x509_crt_get_dn(cert, NULL, &size);
903         if (size == 0) {
904                 Log(LOG_ERR, "gnutls_x509_crt_get_dn: size == 0");
905                 return;
906         }
907         if (err && err != GNUTLS_E_SHORT_MEMORY_BUFFER)
908                 goto err_crt_get;
909         dn = LogMalloc(size);
910         if (!dn)
911                 return;
912         err = gnutls_x509_crt_get_dn(cert, dn, &size);
913         if (err)
914                 goto err_crt_get;
915         gnutls_x509_crt_get_issuer_dn(cert, NULL, &size);
916         assert(size);
917         issuer_dn = LogMalloc(size);
918         if (!issuer_dn) {
919                 Log(level, "%s: Distinguished Name \"%s\".", msg, dn);
920                 free(dn);
921                 return;
922         }
923         gnutls_x509_crt_get_issuer_dn(cert, issuer_dn, &size);
924         Log(level, "%s: Distinguished Name \"%s\", Issuer \"%s\".", msg, dn,
925             issuer_dn);
926         free(dn);
927         free(issuer_dn);
928         return;
929
930       err_crt_get:
931         Log(LOG_ERR, "gnutls_x509_crt_get_dn: %s", gnutls_strerror(err));
932         return;
933 }
934 #endif
935
936
937 static void
938 ConnSSL_LogCertInfo( CONNECTION * c, bool connect)
939 {
940         bool cert_seen = false, cert_ok = false;
941         char msg[128];
942 #ifdef HAVE_LIBSSL
943         const char *comp_alg = "no compression";
944         const void *comp;
945         X509 *peer_cert = NULL;
946         SSL *ssl = c->ssl_state.ssl;
947
948         assert(ssl);
949
950         comp = SSL_get_current_compression(ssl);
951         if (comp)
952                 comp_alg = SSL_COMP_get_name(comp);
953         Log(LOG_INFO, "Connection %d: initialized %s using cipher %s, %s.",
954             c->sock, SSL_get_version(ssl), SSL_get_cipher(ssl), comp_alg);
955         peer_cert = SSL_get_peer_certificate(ssl);
956         if (peer_cert) {
957                 cert_seen = true;
958
959                 if (connect) {
960                         /* Outgoing connection. Verify the remote server! */
961                         int err = SSL_get_verify_result(ssl);
962                         if (err == X509_V_OK) {
963                                 const char *peername = SSL_get0_peername(ssl);
964                                 if (peername != NULL)
965                                         cert_ok = true;
966                                 LogDebug("X509_V_OK, peername = '%s'", peername);
967                         } else
968                                 Log(LOG_WARNING, "Certificate validation failed: %s!",
969                                     X509_verify_cert_error_string(err));
970
971                         snprintf(msg, sizeof(msg), "Got %svalid server certificate",
972                                  cert_ok ? "" : "in");
973                         LogOpenSSL_CertInfo(LOG_INFO, peer_cert, msg);
974                 } else {
975                         /* Incoming connection.
976                          * Accept all certificates, don't depend on their
977                          * validity: for example, we don't know the hostname
978                          * to check, because we not yet even know if this is a
979                          * server connection at all and if so, which one, so we
980                          * don't know a host name to look for. On the other
981                          * hand we want client certificates, for example for
982                          * "CertFP" authentication with services ... */
983                         LogOpenSSL_CertInfo(LOG_INFO, peer_cert,
984                                             "Got unchecked peer certificate");
985                 }
986
987                 X509_free(peer_cert);
988         }
989 #endif
990 #ifdef HAVE_LIBGNUTLS
991         unsigned int status;
992         gnutls_credentials_type_t cred;
993         gnutls_session_t sess = c->ssl_state.gnutls_session;
994         gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
995
996         Log(LOG_INFO, "Connection %d: initialized %s using cipher %s-%s.",
997             c->sock,
998             gnutls_protocol_get_name(gnutls_protocol_get_version(sess)),
999             gnutls_cipher_get_name(cipher),
1000             gnutls_mac_get_name(gnutls_mac_get(sess)));
1001         cred = gnutls_auth_get_type(c->ssl_state.gnutls_session);
1002         if (cred == GNUTLS_CRD_CERTIFICATE) {
1003                 gnutls_x509_crt_t cert;
1004                 unsigned cert_list_size;
1005                 const gnutls_datum_t *cert_list =
1006                     gnutls_certificate_get_peers(sess, &cert_list_size);
1007
1008                 if (!cert_list || cert_list_size == 0)
1009                         goto done_cn_validation;
1010
1011                 cert_seen = true;
1012                 int err = gnutls_x509_crt_init(&cert);
1013                 if (err < 0) {
1014                         Log(LOG_ERR,
1015                             "Failed to initialize x509 certificate: %s",
1016                             gnutls_strerror(err));
1017                         goto done_cn_validation;
1018                 }
1019                 err = gnutls_x509_crt_import(cert, cert_list,
1020                                            GNUTLS_X509_FMT_DER);
1021                 if (err < 0) {
1022                         Log(LOG_ERR, "Failed to parse the certificate: %s",
1023                             gnutls_strerror(err));
1024                         goto done_cn_validation;
1025                 }
1026
1027                 if (connect) {
1028                         int verify =
1029                             gnutls_certificate_verify_peers2(c->
1030                                                              ssl_state.gnutls_session,
1031                                                              &status);
1032                         if (verify < 0) {
1033                                 Log(LOG_ERR,
1034                                     "gnutls_certificate_verify_peers2 failed: %s",
1035                                     gnutls_strerror(verify));
1036                                 goto done_cn_validation;
1037                         } else if (status) {
1038                                 gnutls_datum_t out;
1039
1040                                 if (gnutls_certificate_verification_status_print
1041                                     (status, gnutls_certificate_type_get(sess), &out,
1042                                      0) == GNUTLS_E_SUCCESS) {
1043                                         Log(LOG_ERR,
1044                                             "Certificate validation failed: %s",
1045                                             out.data);
1046                                         gnutls_free(out.data);
1047                                 }
1048                         }
1049
1050                         err = gnutls_x509_crt_check_hostname(cert, c->host);
1051                         if (err == 0)
1052                                 Log(LOG_ERR,
1053                                     "Failed to verify the hostname, expected \"%s\"",
1054                                     c->host);
1055                         else
1056                                 cert_ok = verify == 0 && status == 0;
1057
1058                         snprintf(msg, sizeof(msg), "Got %svalid server certificate",
1059                                 cert_ok ? "" : "in");
1060                         LogGnuTLS_CertInfo(LOG_INFO, cert, msg);
1061                 } else {
1062                         /* Incoming connection. Please see comments for OpenSSL! */
1063                         LogGnuTLS_CertInfo(LOG_INFO, cert,
1064                                             "Got unchecked peer certificate");
1065                 }
1066
1067                 gnutls_x509_crt_deinit(cert);
1068 done_cn_validation:
1069                 ;
1070         }
1071 #endif
1072         /*
1073          * can be used later to check if connection was authenticated, e.g.
1074          * if inbound connection tries to register itself as server.
1075          * Could also restrict /OPER to authenticated connections, etc.
1076          */
1077         if (cert_ok)
1078                 Conn_OPTION_ADD(c, CONN_SSL_PEERCERT_OK);
1079         if (!cert_seen)
1080                 Log(LOG_INFO, "Peer did not present a certificate.");
1081 }
1082
1083
1084 /*
1085  Accept incoming SSL connection.
1086  Return Values:
1087          1: SSL Connection established
1088          0: try again
1089         -1: SSL Connection not established due to fatal error.
1090 */
1091 int
1092 ConnSSL_Accept( CONNECTION *c )
1093 {
1094         assert(c != NULL);
1095         if (!Conn_OPTION_ISSET(c, CONN_SSL)) {
1096 #ifdef HAVE_LIBGNUTLS
1097                 int err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_SERVER);
1098                 if (err) {
1099                         Log(LOG_ERR, "Failed to initialize new SSL session: %s",
1100                             gnutls_strerror(err));
1101                         return false;
1102                 }
1103 #endif
1104                 if (!ConnSSL_Init_SSL(c))
1105                         return -1;
1106         }
1107         return ConnectAccept(c, false );
1108 }
1109
1110
1111 int
1112 ConnSSL_Connect( CONNECTION *c )
1113 {
1114         assert(c != NULL);
1115 #ifdef HAVE_LIBSSL
1116         assert(c->ssl_state.ssl);
1117 #endif
1118         assert(Conn_OPTION_ISSET(c, CONN_SSL));
1119         return ConnectAccept(c, true);
1120 }
1121
1122 static int
1123 ConnSSL_InitCertFp( CONNECTION *c )
1124 {
1125         const char hex[] = "0123456789abcdef";
1126         int i;
1127
1128 #ifdef HAVE_LIBSSL
1129         unsigned char digest[EVP_MAX_MD_SIZE];
1130         unsigned int digest_size;
1131         X509 *cert;
1132
1133         cert = SSL_get_peer_certificate(c->ssl_state.ssl);
1134         if (!cert)
1135                 return 0;
1136
1137         if (!X509_digest(cert, EVP_sha256(), digest, &digest_size)) {
1138                 X509_free(cert);
1139                 return 0;
1140         }
1141
1142         X509_free(cert);
1143 #endif /* HAVE_LIBSSL */
1144 #ifdef HAVE_LIBGNUTLS
1145         gnutls_x509_crt_t cert;
1146         unsigned int cert_list_size;
1147         const gnutls_datum_t *cert_list;
1148         unsigned char digest[MAX_HASH_SIZE];
1149         size_t digest_size;
1150
1151         if (gnutls_certificate_type_get(c->ssl_state.gnutls_session) !=
1152                                         GNUTLS_CRT_X509)
1153                 return 0;
1154
1155         if (gnutls_x509_crt_init(&cert) != GNUTLS_E_SUCCESS)
1156                 return 0;
1157
1158         cert_list_size = 0;
1159         cert_list = gnutls_certificate_get_peers(c->ssl_state.gnutls_session,
1160                                                  &cert_list_size);
1161         if (!cert_list) {
1162                 gnutls_x509_crt_deinit(cert);
1163                 return 0;
1164         }
1165
1166         if (gnutls_x509_crt_import(cert, &cert_list[0],
1167                                    GNUTLS_X509_FMT_DER) != GNUTLS_E_SUCCESS) {
1168                 gnutls_x509_crt_deinit(cert);
1169                 return 0;
1170         }
1171
1172         digest_size = sizeof(digest);
1173         if (gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_SHA256, digest,
1174                                             &digest_size)) {
1175                 gnutls_x509_crt_deinit(cert);
1176                 return 0;
1177         }
1178
1179         gnutls_x509_crt_deinit(cert);
1180 #endif /* HAVE_LIBGNUTLS */
1181
1182         assert(c->ssl_state.fingerprint == NULL);
1183
1184         c->ssl_state.fingerprint = malloc(SHA256_STRING_LEN);
1185         if (!c->ssl_state.fingerprint)
1186                 return 0;
1187
1188         for (i = 0; i < (int)digest_size; i++) {
1189                 c->ssl_state.fingerprint[i * 2] = hex[digest[i] / 16];
1190                 c->ssl_state.fingerprint[i * 2 + 1] = hex[digest[i] % 16];
1191         }
1192         c->ssl_state.fingerprint[i * 2] = '\0';
1193
1194         return 1;
1195 }
1196
1197 /* accept/connect wrapper. if connect is true, connect to peer, otherwise wait for incoming connection */
1198 static int
1199 ConnectAccept( CONNECTION *c, bool connect)
1200 {
1201         int ret;
1202 #ifdef HAVE_LIBSSL
1203         SSL *ssl = c->ssl_state.ssl;
1204         assert(ssl != NULL);
1205
1206         ret = connect ? SSL_connect(ssl) : SSL_accept(ssl);
1207         if (1 != ret)
1208                 return ConnSSL_HandleError(c, ret, connect ? "SSL_connect": "SSL_accept");
1209 #endif
1210 #ifdef HAVE_LIBGNUTLS
1211         (void) connect;
1212         ret = gnutls_handshake(c->ssl_state.gnutls_session);
1213         if (ret)
1214                 return ConnSSL_HandleError(c, ret, "gnutls_handshake");
1215 #endif /* _GNUTLS */
1216         (void)ConnSSL_InitCertFp(c);
1217
1218         Conn_OPTION_DEL(c, (CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ|CONN_SSL_CONNECT));
1219         ConnSSL_LogCertInfo(c, connect);
1220
1221         Conn_StartLogin(CONNECTION2ID(c));
1222         return 1;
1223 }
1224
1225
1226 ssize_t
1227 ConnSSL_Write(CONNECTION *c, const void *buf, size_t count)
1228 {
1229         ssize_t bw;
1230
1231         Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
1232
1233         assert(count > 0);
1234 #ifdef HAVE_LIBSSL
1235         bw = (ssize_t) SSL_write(c->ssl_state.ssl, buf, count);
1236 #endif
1237 #ifdef HAVE_LIBGNUTLS
1238         bw = gnutls_write(c->ssl_state.gnutls_session, buf, count);
1239 #endif
1240         if (bw > 0)
1241                 return bw;
1242         if (ConnSSL_HandleError( c, bw, "ConnSSL_Write") == 0)
1243                 errno = EAGAIN; /* try again */
1244         return -1;
1245 }
1246
1247
1248 ssize_t
1249 ConnSSL_Read(CONNECTION *c, void * buf, size_t count)
1250 {
1251         ssize_t br;
1252
1253         Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
1254 #ifdef HAVE_LIBSSL
1255         br = (ssize_t) SSL_read(c->ssl_state.ssl, buf, count);
1256         if (br > 0)     /* on EOF we have to call ConnSSL_HandleError(), see SSL_read(3) */
1257                 return br;
1258 #endif
1259 #ifdef HAVE_LIBGNUTLS
1260         br = gnutls_read(c->ssl_state.gnutls_session, buf, count);
1261         if (br >= 0)    /* on EOF we must _not_ call ConnSSL_HandleError, see gnutls_record_recv(3) */
1262                 return br;
1263 #endif
1264         /* error on read: switch ConnSSL_HandleError() return values -> 0 is "try again", so return -1 and set EAGAIN */
1265         if (ConnSSL_HandleError(c, br, "ConnSSL_Read") == 0) {
1266                 errno = EAGAIN;
1267                 return -1;
1268         }
1269         return 0;
1270 }
1271
1272
1273 bool
1274 ConnSSL_GetCipherInfo(CONNECTION *c, char *buf, size_t len)
1275 {
1276 #ifdef HAVE_LIBSSL
1277         char *nl;
1278         SSL *ssl = c->ssl_state.ssl;
1279
1280         if (!ssl)
1281                 return false;
1282         *buf = 0;
1283         SSL_CIPHER_description(SSL_get_current_cipher(ssl), buf, len);
1284         nl = strchr(buf, '\n');
1285         if (nl)
1286                 *nl = 0;
1287         return true;
1288 #endif
1289 #ifdef HAVE_LIBGNUTLS
1290         if (Conn_OPTION_ISSET(c, CONN_SSL)) {
1291                 const char *name_cipher, *name_mac, *name_proto, *name_keyexchange;
1292                 unsigned keysize;
1293
1294                 gnutls_session_t sess = c->ssl_state.gnutls_session;
1295                 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
1296                 name_cipher = gnutls_cipher_get_name(cipher);
1297                 name_mac = gnutls_mac_get_name(gnutls_mac_get(sess));
1298                 keysize = gnutls_cipher_get_key_size(cipher) * 8;
1299                 name_proto = gnutls_protocol_get_name(gnutls_protocol_get_version(sess));
1300                 name_keyexchange = gnutls_kx_get_name(gnutls_kx_get(sess));
1301
1302                 return snprintf(buf, len, "%s-%s%15s Kx=%s      Enc=%s(%u) Mac=%s",
1303                         name_cipher, name_mac, name_proto, name_keyexchange, name_cipher, keysize, name_mac) > 0;
1304         }
1305         return false;
1306 #endif
1307 }
1308
1309 char *
1310 ConnSSL_GetCertFp(CONNECTION *c)
1311 {
1312         return c->ssl_state.fingerprint;
1313 }
1314
1315 bool
1316 ConnSSL_SetCertFp(CONNECTION *c, const char *fingerprint)
1317 {
1318         assert (c != NULL);
1319         c->ssl_state.fingerprint = strndup(fingerprint, SHA256_STRING_LEN - 1);
1320         return c->ssl_state.fingerprint != NULL;
1321 }
1322 #else
1323
1324 bool
1325 ConnSSL_InitLibrary(void)
1326 {
1327         return true;
1328 }
1329
1330 #endif /* SSL_SUPPORT */
1331 /* -eof- */