Commit | Line | Data |
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059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
3386088d | 5 | /* Copyright (c) University of Cambridge 1995 - 2015 */ |
059ec3d9 PH |
6 | /* See the file NOTICE for conditions of use and distribution. */ |
7 | ||
f5d78688 JH |
8 | /* Portions Copyright (c) The OpenSSL Project 1999 */ |
9 | ||
059ec3d9 PH |
10 | /* This module provides the TLS (aka SSL) support for Exim using the OpenSSL |
11 | library. It is #included into the tls.c file when that library is used. The | |
12 | code herein is based on a patch that was originally contributed by Steve | |
13 | Haslam. It was adapted from stunnel, a GPL program by Michal Trojnara. | |
14 | ||
15 | No cryptographic code is included in Exim. All this module does is to call | |
16 | functions from the OpenSSL library. */ | |
17 | ||
18 | ||
19 | /* Heading stuff */ | |
20 | ||
21 | #include <openssl/lhash.h> | |
22 | #include <openssl/ssl.h> | |
23 | #include <openssl/err.h> | |
24 | #include <openssl/rand.h> | |
10ca4f1c JH |
25 | #ifndef OPENSSL_NO_ECDH |
26 | # include <openssl/ec.h> | |
27 | #endif | |
f2de3a33 | 28 | #ifndef DISABLE_OCSP |
e51c7be2 | 29 | # include <openssl/ocsp.h> |
3f7eeb86 | 30 | #endif |
85098ee7 JH |
31 | #ifdef EXPERIMENTAL_DANE |
32 | # include <danessl.h> | |
33 | #endif | |
34 | ||
3f7eeb86 | 35 | |
f2de3a33 JH |
36 | #ifndef DISABLE_OCSP |
37 | # define EXIM_OCSP_SKEW_SECONDS (300L) | |
38 | # define EXIM_OCSP_MAX_AGE (-1L) | |
3f7eeb86 | 39 | #endif |
059ec3d9 | 40 | |
3bcbbbe2 | 41 | #if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT) |
e51c7be2 | 42 | # define EXIM_HAVE_OPENSSL_TLSEXT |
3bcbbbe2 | 43 | #endif |
c8dfb21d JH |
44 | #if OPENSSL_VERSION_NUMBER >= 0x00908000L |
45 | # define EXIM_HAVE_RSA_GENKEY_EX | |
46 | #endif | |
47 | #if OPENSSL_VERSION_NUMBER >= 0x10100000L | |
48 | # define EXIM_HAVE_OCSP_RESP_COUNT | |
49 | #else | |
50 | # define EXIM_HAVE_EPHEM_RSA_KEX | |
51 | # define EXIM_HAVE_RAND_PSEUDO | |
52 | #endif | |
53 | #if (OPENSSL_VERSION_NUMBER >= 0x0090800fL) && !defined(OPENSSL_NO_SHA256) | |
54 | # define EXIM_HAVE_SHA256 | |
55 | #endif | |
34e3241d PP |
56 | |
57 | /* | |
58 | * X509_check_host provides sane certificate hostname checking, but was added | |
59 | * to OpenSSL late, after other projects forked off the code-base. So in | |
60 | * addition to guarding against the base version number, beware that LibreSSL | |
61 | * does not (at this time) support this function. | |
62 | * | |
63 | * If LibreSSL gains a different API, perhaps via libtls, then we'll probably | |
64 | * opt to disentangle and ask a LibreSSL user to provide glue for a third | |
65 | * crypto provider for libtls instead of continuing to tie the OpenSSL glue | |
66 | * into even twistier knots. If LibreSSL gains the same API, we can just | |
67 | * change this guard and punt the issue for a while longer. | |
68 | */ | |
69 | #ifndef LIBRESSL_VERSION_NUMBER | |
70 | # if OPENSSL_VERSION_NUMBER >= 0x010100000L | |
71 | # define EXIM_HAVE_OPENSSL_CHECKHOST | |
72 | # endif | |
73 | # if OPENSSL_VERSION_NUMBER >= 0x010000000L \ | |
2dfb468b | 74 | && (OPENSSL_VERSION_NUMBER & 0x0000ff000L) >= 0x000002000L |
34e3241d PP |
75 | # define EXIM_HAVE_OPENSSL_CHECKHOST |
76 | # endif | |
10ca4f1c JH |
77 | |
78 | # if !defined(OPENSSL_NO_ECDH) | |
79 | # if OPENSSL_VERSION_NUMBER >= 0x0090800fL | |
80 | # define EXIM_HAVE_ECDH | |
81 | # endif | |
82 | # if OPENSSL_VERSION_NUMBER >= 0x10002000L | |
c8dfb21d JH |
83 | # if OPENSSL_VERSION_NUMBER < 0x10100000L |
84 | # define EXIM_HAVE_OPENSSL_ECDH_AUTO | |
85 | # endif | |
10ca4f1c JH |
86 | # define EXIM_HAVE_OPENSSL_EC_NIST2NID |
87 | # endif | |
88 | # endif | |
2dfb468b | 89 | #endif |
3bcbbbe2 | 90 | |
67791ce4 JH |
91 | #if !defined(EXIM_HAVE_OPENSSL_TLSEXT) && !defined(DISABLE_OCSP) |
92 | # warning "OpenSSL library version too old; define DISABLE_OCSP in Makefile" | |
93 | # define DISABLE_OCSP | |
94 | #endif | |
95 | ||
059ec3d9 PH |
96 | /* Structure for collecting random data for seeding. */ |
97 | ||
98 | typedef struct randstuff { | |
9e3331ea TK |
99 | struct timeval tv; |
100 | pid_t p; | |
059ec3d9 PH |
101 | } randstuff; |
102 | ||
103 | /* Local static variables */ | |
104 | ||
a2ff477a JH |
105 | static BOOL client_verify_callback_called = FALSE; |
106 | static BOOL server_verify_callback_called = FALSE; | |
059ec3d9 PH |
107 | static const uschar *sid_ctx = US"exim"; |
108 | ||
d4f09789 PP |
109 | /* We have three different contexts to care about. |
110 | ||
111 | Simple case: client, `client_ctx` | |
112 | As a client, we can be doing a callout or cut-through delivery while receiving | |
113 | a message. So we have a client context, which should have options initialised | |
114 | from the SMTP Transport. | |
115 | ||
116 | Server: | |
117 | There are two cases: with and without ServerNameIndication from the client. | |
118 | Given TLS SNI, we can be using different keys, certs and various other | |
119 | configuration settings, because they're re-expanded with $tls_sni set. This | |
120 | allows vhosting with TLS. This SNI is sent in the handshake. | |
121 | A client might not send SNI, so we need a fallback, and an initial setup too. | |
122 | So as a server, we start out using `server_ctx`. | |
123 | If SNI is sent by the client, then we as server, mid-negotiation, try to clone | |
124 | `server_sni` from `server_ctx` and then initialise settings by re-expanding | |
125 | configuration. | |
126 | */ | |
127 | ||
817d9f57 JH |
128 | static SSL_CTX *client_ctx = NULL; |
129 | static SSL_CTX *server_ctx = NULL; | |
130 | static SSL *client_ssl = NULL; | |
131 | static SSL *server_ssl = NULL; | |
389ca47a | 132 | |
35731706 | 133 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
817d9f57 | 134 | static SSL_CTX *server_sni = NULL; |
35731706 | 135 | #endif |
059ec3d9 PH |
136 | |
137 | static char ssl_errstring[256]; | |
138 | ||
139 | static int ssl_session_timeout = 200; | |
a2ff477a JH |
140 | static BOOL client_verify_optional = FALSE; |
141 | static BOOL server_verify_optional = FALSE; | |
059ec3d9 | 142 | |
f5d78688 | 143 | static BOOL reexpand_tls_files_for_sni = FALSE; |
059ec3d9 PH |
144 | |
145 | ||
7be682ca PP |
146 | typedef struct tls_ext_ctx_cb { |
147 | uschar *certificate; | |
148 | uschar *privatekey; | |
f2de3a33 | 149 | #ifndef DISABLE_OCSP |
f5d78688 JH |
150 | BOOL is_server; |
151 | union { | |
152 | struct { | |
153 | uschar *file; | |
154 | uschar *file_expanded; | |
155 | OCSP_RESPONSE *response; | |
156 | } server; | |
157 | struct { | |
44662487 JH |
158 | X509_STORE *verify_store; /* non-null if status requested */ |
159 | BOOL verify_required; | |
f5d78688 JH |
160 | } client; |
161 | } u_ocsp; | |
3f7eeb86 | 162 | #endif |
7be682ca PP |
163 | uschar *dhparam; |
164 | /* these are cached from first expand */ | |
165 | uschar *server_cipher_list; | |
166 | /* only passed down to tls_error: */ | |
167 | host_item *host; | |
55414b25 | 168 | const uschar * verify_cert_hostnames; |
0cbf2b82 | 169 | #ifndef DISABLE_EVENT |
a7538db1 JH |
170 | uschar * event_action; |
171 | #endif | |
7be682ca PP |
172 | } tls_ext_ctx_cb; |
173 | ||
174 | /* should figure out a cleanup of API to handle state preserved per | |
175 | implementation, for various reasons, which can be void * in the APIs. | |
176 | For now, we hack around it. */ | |
817d9f57 JH |
177 | tls_ext_ctx_cb *client_static_cbinfo = NULL; |
178 | tls_ext_ctx_cb *server_static_cbinfo = NULL; | |
7be682ca PP |
179 | |
180 | static int | |
983207c1 JH |
181 | setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host, BOOL optional, |
182 | int (*cert_vfy_cb)(int, X509_STORE_CTX *) ); | |
059ec3d9 | 183 | |
3f7eeb86 | 184 | /* Callbacks */ |
3bcbbbe2 | 185 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
3f7eeb86 | 186 | static int tls_servername_cb(SSL *s, int *ad ARG_UNUSED, void *arg); |
3bcbbbe2 | 187 | #endif |
f2de3a33 | 188 | #ifndef DISABLE_OCSP |
f5d78688 | 189 | static int tls_server_stapling_cb(SSL *s, void *arg); |
3f7eeb86 PP |
190 | #endif |
191 | ||
059ec3d9 PH |
192 | |
193 | /************************************************* | |
194 | * Handle TLS error * | |
195 | *************************************************/ | |
196 | ||
197 | /* Called from lots of places when errors occur before actually starting to do | |
198 | the TLS handshake, that is, while the session is still in clear. Always returns | |
199 | DEFER for a server and FAIL for a client so that most calls can use "return | |
200 | tls_error(...)" to do this processing and then give an appropriate return. A | |
201 | single function is used for both server and client, because it is called from | |
202 | some shared functions. | |
203 | ||
204 | Argument: | |
205 | prefix text to include in the logged error | |
206 | host NULL if setting up a server; | |
207 | the connected host if setting up a client | |
7199e1ee | 208 | msg error message or NULL if we should ask OpenSSL |
059ec3d9 PH |
209 | |
210 | Returns: OK/DEFER/FAIL | |
211 | */ | |
212 | ||
213 | static int | |
b8b1b5cb | 214 | tls_error(uschar * prefix, const host_item * host, uschar * msg) |
059ec3d9 | 215 | { |
c562fd30 | 216 | if (!msg) |
7199e1ee TF |
217 | { |
218 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
5ca6d115 | 219 | msg = (uschar *)ssl_errstring; |
7199e1ee TF |
220 | } |
221 | ||
c562fd30 JH |
222 | if (host) |
223 | { | |
224 | log_write(0, LOG_MAIN, "H=%s [%s] TLS error on connection (%s): %s", | |
225 | host->name, host->address, prefix, msg); | |
226 | return FAIL; | |
227 | } | |
228 | else | |
059ec3d9 | 229 | { |
7199e1ee | 230 | uschar *conn_info = smtp_get_connection_info(); |
5ca6d115 | 231 | if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) |
7199e1ee | 232 | conn_info += 5; |
c562fd30 | 233 | /* I'd like to get separated H= here, but too hard for now */ |
7199e1ee TF |
234 | log_write(0, LOG_MAIN, "TLS error on %s (%s): %s", |
235 | conn_info, prefix, msg); | |
059ec3d9 PH |
236 | return DEFER; |
237 | } | |
059ec3d9 PH |
238 | } |
239 | ||
240 | ||
241 | ||
c8dfb21d | 242 | #ifdef EXIM_HAVE_EPHEM_RSA_KEX |
059ec3d9 PH |
243 | /************************************************* |
244 | * Callback to generate RSA key * | |
245 | *************************************************/ | |
246 | ||
247 | /* | |
248 | Arguments: | |
249 | s SSL connection | |
250 | export not used | |
251 | keylength keylength | |
252 | ||
253 | Returns: pointer to generated key | |
254 | */ | |
255 | ||
256 | static RSA * | |
257 | rsa_callback(SSL *s, int export, int keylength) | |
258 | { | |
259 | RSA *rsa_key; | |
c8dfb21d JH |
260 | #ifdef EXIM_HAVE_RSA_GENKEY_EX |
261 | BIGNUM *bn = BN_new(); | |
262 | #endif | |
263 | ||
059ec3d9 PH |
264 | export = export; /* Shut picky compilers up */ |
265 | DEBUG(D_tls) debug_printf("Generating %d bit RSA key...\n", keylength); | |
c8dfb21d JH |
266 | |
267 | #ifdef EXIM_HAVE_RSA_GENKEY_EX | |
268 | if ( !BN_set_word(bn, (unsigned long)RSA_F4) | |
269 | || !RSA_generate_key_ex(rsa_key, keylength, bn, NULL) | |
270 | ) | |
271 | #else | |
059ec3d9 PH |
272 | rsa_key = RSA_generate_key(keylength, RSA_F4, NULL, NULL); |
273 | if (rsa_key == NULL) | |
c8dfb21d JH |
274 | #endif |
275 | ||
059ec3d9 PH |
276 | { |
277 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
278 | log_write(0, LOG_MAIN|LOG_PANIC, "TLS error (RSA_generate_key): %s", | |
279 | ssl_errstring); | |
280 | return NULL; | |
281 | } | |
282 | return rsa_key; | |
283 | } | |
c8dfb21d | 284 | #endif |
059ec3d9 PH |
285 | |
286 | ||
287 | ||
f5d78688 | 288 | /* Extreme debug |
f2de3a33 | 289 | #ifndef DISABLE_OCSP |
f5d78688 JH |
290 | void |
291 | x509_store_dump_cert_s_names(X509_STORE * store) | |
292 | { | |
293 | STACK_OF(X509_OBJECT) * roots= store->objs; | |
294 | int i; | |
295 | static uschar name[256]; | |
296 | ||
297 | for(i= 0; i<sk_X509_OBJECT_num(roots); i++) | |
298 | { | |
299 | X509_OBJECT * tmp_obj= sk_X509_OBJECT_value(roots, i); | |
300 | if(tmp_obj->type == X509_LU_X509) | |
301 | { | |
302 | X509 * current_cert= tmp_obj->data.x509; | |
303 | X509_NAME_oneline(X509_get_subject_name(current_cert), CS name, sizeof(name)); | |
f69979cf | 304 | name[sizeof(name)-1] = '\0'; |
f5d78688 JH |
305 | debug_printf(" %s\n", name); |
306 | } | |
307 | } | |
308 | } | |
309 | #endif | |
310 | */ | |
311 | ||
059ec3d9 | 312 | |
0cbf2b82 | 313 | #ifndef DISABLE_EVENT |
f69979cf JH |
314 | static int |
315 | verify_event(tls_support * tlsp, X509 * cert, int depth, const uschar * dn, | |
316 | BOOL *calledp, const BOOL *optionalp, const uschar * what) | |
317 | { | |
318 | uschar * ev; | |
319 | uschar * yield; | |
320 | X509 * old_cert; | |
321 | ||
322 | ev = tlsp == &tls_out ? client_static_cbinfo->event_action : event_action; | |
323 | if (ev) | |
324 | { | |
aaba7d03 | 325 | DEBUG(D_tls) debug_printf("verify_event: %s %d\n", what, depth); |
f69979cf JH |
326 | old_cert = tlsp->peercert; |
327 | tlsp->peercert = X509_dup(cert); | |
328 | /* NB we do not bother setting peerdn */ | |
329 | if ((yield = event_raise(ev, US"tls:cert", string_sprintf("%d", depth)))) | |
330 | { | |
331 | log_write(0, LOG_MAIN, "[%s] %s verify denied by event-action: " | |
332 | "depth=%d cert=%s: %s", | |
333 | tlsp == &tls_out ? deliver_host_address : sender_host_address, | |
334 | what, depth, dn, yield); | |
335 | *calledp = TRUE; | |
336 | if (!*optionalp) | |
337 | { | |
338 | if (old_cert) tlsp->peercert = old_cert; /* restore 1st failing cert */ | |
339 | return 1; /* reject (leaving peercert set) */ | |
340 | } | |
341 | DEBUG(D_tls) debug_printf("Event-action verify failure overridden " | |
342 | "(host in tls_try_verify_hosts)\n"); | |
343 | } | |
344 | X509_free(tlsp->peercert); | |
345 | tlsp->peercert = old_cert; | |
346 | } | |
347 | return 0; | |
348 | } | |
349 | #endif | |
350 | ||
059ec3d9 PH |
351 | /************************************************* |
352 | * Callback for verification * | |
353 | *************************************************/ | |
354 | ||
355 | /* The SSL library does certificate verification if set up to do so. This | |
356 | callback has the current yes/no state is in "state". If verification succeeded, | |
f69979cf JH |
357 | we set the certificate-verified flag. If verification failed, what happens |
358 | depends on whether the client is required to present a verifiable certificate | |
359 | or not. | |
059ec3d9 PH |
360 | |
361 | If verification is optional, we change the state to yes, but still log the | |
362 | verification error. For some reason (it really would help to have proper | |
363 | documentation of OpenSSL), this callback function then gets called again, this | |
f69979cf JH |
364 | time with state = 1. We must take care not to set the private verified flag on |
365 | the second time through. | |
059ec3d9 PH |
366 | |
367 | Note: this function is not called if the client fails to present a certificate | |
368 | when asked. We get here only if a certificate has been received. Handling of | |
369 | optional verification for this case is done when requesting SSL to verify, by | |
370 | setting SSL_VERIFY_FAIL_IF_NO_PEER_CERT in the non-optional case. | |
371 | ||
a7538db1 JH |
372 | May be called multiple times for different issues with a certificate, even |
373 | for a given "depth" in the certificate chain. | |
374 | ||
059ec3d9 | 375 | Arguments: |
f2f2c91b JH |
376 | preverify_ok current yes/no state as 1/0 |
377 | x509ctx certificate information. | |
378 | tlsp per-direction (client vs. server) support data | |
379 | calledp has-been-called flag | |
380 | optionalp verification-is-optional flag | |
059ec3d9 | 381 | |
f2f2c91b | 382 | Returns: 0 if verification should fail, otherwise 1 |
059ec3d9 PH |
383 | */ |
384 | ||
385 | static int | |
f2f2c91b | 386 | verify_callback(int preverify_ok, X509_STORE_CTX *x509ctx, |
421aff85 | 387 | tls_support *tlsp, BOOL *calledp, BOOL *optionalp) |
059ec3d9 | 388 | { |
421aff85 | 389 | X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx); |
a7538db1 | 390 | int depth = X509_STORE_CTX_get_error_depth(x509ctx); |
f69979cf | 391 | uschar dn[256]; |
059ec3d9 | 392 | |
f69979cf JH |
393 | X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn)); |
394 | dn[sizeof(dn)-1] = '\0'; | |
059ec3d9 | 395 | |
f2f2c91b | 396 | if (preverify_ok == 0) |
059ec3d9 | 397 | { |
4c01d6ab JH |
398 | log_write(0, LOG_MAIN, "[%s] SSL verify error: depth=%d error=%s cert=%s", |
399 | tlsp == &tls_out ? deliver_host_address : sender_host_address, | |
a7538db1 | 400 | depth, |
421aff85 | 401 | X509_verify_cert_error_string(X509_STORE_CTX_get_error(x509ctx)), |
f69979cf | 402 | dn); |
a2ff477a | 403 | *calledp = TRUE; |
9d1c15ef JH |
404 | if (!*optionalp) |
405 | { | |
f69979cf JH |
406 | if (!tlsp->peercert) |
407 | tlsp->peercert = X509_dup(cert); /* record failing cert */ | |
408 | return 0; /* reject */ | |
9d1c15ef | 409 | } |
059ec3d9 PH |
410 | DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in " |
411 | "tls_try_verify_hosts)\n"); | |
059ec3d9 PH |
412 | } |
413 | ||
a7538db1 | 414 | else if (depth != 0) |
059ec3d9 | 415 | { |
f69979cf | 416 | DEBUG(D_tls) debug_printf("SSL verify ok: depth=%d SN=%s\n", depth, dn); |
f2de3a33 | 417 | #ifndef DISABLE_OCSP |
f5d78688 JH |
418 | if (tlsp == &tls_out && client_static_cbinfo->u_ocsp.client.verify_store) |
419 | { /* client, wanting stapling */ | |
420 | /* Add the server cert's signing chain as the one | |
421 | for the verification of the OCSP stapled information. */ | |
94431adb | 422 | |
f5d78688 | 423 | if (!X509_STORE_add_cert(client_static_cbinfo->u_ocsp.client.verify_store, |
421aff85 | 424 | cert)) |
f5d78688 JH |
425 | ERR_clear_error(); |
426 | } | |
a7538db1 | 427 | #endif |
0cbf2b82 | 428 | #ifndef DISABLE_EVENT |
f69979cf JH |
429 | if (verify_event(tlsp, cert, depth, dn, calledp, optionalp, US"SSL")) |
430 | return 0; /* reject, with peercert set */ | |
f5d78688 | 431 | #endif |
059ec3d9 PH |
432 | } |
433 | else | |
434 | { | |
55414b25 | 435 | const uschar * verify_cert_hostnames; |
e51c7be2 | 436 | |
e51c7be2 JH |
437 | if ( tlsp == &tls_out |
438 | && ((verify_cert_hostnames = client_static_cbinfo->verify_cert_hostnames))) | |
439 | /* client, wanting hostname check */ | |
e51c7be2 | 440 | { |
f69979cf | 441 | |
740f36d4 | 442 | #ifdef EXIM_HAVE_OPENSSL_CHECKHOST |
f69979cf JH |
443 | # ifndef X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS |
444 | # define X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS 0 | |
445 | # endif | |
446 | # ifndef X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS | |
447 | # define X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS 0 | |
448 | # endif | |
e51c7be2 | 449 | int sep = 0; |
55414b25 | 450 | const uschar * list = verify_cert_hostnames; |
e51c7be2 | 451 | uschar * name; |
d8e7834a JH |
452 | int rc; |
453 | while ((name = string_nextinlist(&list, &sep, NULL, 0))) | |
f40d5be3 | 454 | if ((rc = X509_check_host(cert, CCS name, 0, |
8d692470 | 455 | X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS |
740f36d4 JH |
456 | | X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS, |
457 | NULL))) | |
d8e7834a JH |
458 | { |
459 | if (rc < 0) | |
460 | { | |
93a6fce2 | 461 | log_write(0, LOG_MAIN, "[%s] SSL verify error: internal error", |
4c01d6ab | 462 | tlsp == &tls_out ? deliver_host_address : sender_host_address); |
d8e7834a JH |
463 | name = NULL; |
464 | } | |
e51c7be2 | 465 | break; |
d8e7834a | 466 | } |
e51c7be2 | 467 | if (!name) |
f69979cf | 468 | #else |
e51c7be2 | 469 | if (!tls_is_name_for_cert(verify_cert_hostnames, cert)) |
f69979cf | 470 | #endif |
e51c7be2 JH |
471 | { |
472 | log_write(0, LOG_MAIN, | |
93a6fce2 | 473 | "[%s] SSL verify error: certificate name mismatch: \"%s\"", |
4c01d6ab | 474 | tlsp == &tls_out ? deliver_host_address : sender_host_address, |
f69979cf | 475 | dn); |
a3ef7310 JH |
476 | *calledp = TRUE; |
477 | if (!*optionalp) | |
f69979cf JH |
478 | { |
479 | if (!tlsp->peercert) | |
480 | tlsp->peercert = X509_dup(cert); /* record failing cert */ | |
481 | return 0; /* reject */ | |
482 | } | |
a3ef7310 JH |
483 | DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in " |
484 | "tls_try_verify_hosts)\n"); | |
e51c7be2 | 485 | } |
f69979cf | 486 | } |
e51c7be2 | 487 | |
0cbf2b82 | 488 | #ifndef DISABLE_EVENT |
f69979cf JH |
489 | if (verify_event(tlsp, cert, depth, dn, calledp, optionalp, US"SSL")) |
490 | return 0; /* reject, with peercert set */ | |
e51c7be2 JH |
491 | #endif |
492 | ||
93dcb1c2 | 493 | DEBUG(D_tls) debug_printf("SSL%s verify ok: depth=0 SN=%s\n", |
f69979cf | 494 | *calledp ? "" : " authenticated", dn); |
93dcb1c2 JH |
495 | if (!*calledp) tlsp->certificate_verified = TRUE; |
496 | *calledp = TRUE; | |
059ec3d9 PH |
497 | } |
498 | ||
a7538db1 | 499 | return 1; /* accept, at least for this level */ |
059ec3d9 PH |
500 | } |
501 | ||
a2ff477a | 502 | static int |
f2f2c91b | 503 | verify_callback_client(int preverify_ok, X509_STORE_CTX *x509ctx) |
a2ff477a | 504 | { |
f2f2c91b JH |
505 | return verify_callback(preverify_ok, x509ctx, &tls_out, |
506 | &client_verify_callback_called, &client_verify_optional); | |
a2ff477a JH |
507 | } |
508 | ||
509 | static int | |
f2f2c91b | 510 | verify_callback_server(int preverify_ok, X509_STORE_CTX *x509ctx) |
a2ff477a | 511 | { |
f2f2c91b JH |
512 | return verify_callback(preverify_ok, x509ctx, &tls_in, |
513 | &server_verify_callback_called, &server_verify_optional); | |
a2ff477a JH |
514 | } |
515 | ||
059ec3d9 | 516 | |
e5cccda9 | 517 | #ifdef EXPERIMENTAL_DANE |
53a7196b | 518 | |
e5cccda9 JH |
519 | /* This gets called *by* the dane library verify callback, which interposes |
520 | itself. | |
521 | */ | |
522 | static int | |
f2f2c91b | 523 | verify_callback_client_dane(int preverify_ok, X509_STORE_CTX * x509ctx) |
e5cccda9 JH |
524 | { |
525 | X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx); | |
f69979cf | 526 | uschar dn[256]; |
0cbf2b82 | 527 | #ifndef DISABLE_EVENT |
83b27293 | 528 | int depth = X509_STORE_CTX_get_error_depth(x509ctx); |
f69979cf | 529 | BOOL dummy_called, optional = FALSE; |
83b27293 | 530 | #endif |
e5cccda9 | 531 | |
f69979cf JH |
532 | X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn)); |
533 | dn[sizeof(dn)-1] = '\0'; | |
e5cccda9 | 534 | |
f2f2c91b JH |
535 | DEBUG(D_tls) debug_printf("verify_callback_client_dane: %s depth %d %s\n", |
536 | preverify_ok ? "ok":"BAD", depth, dn); | |
e5cccda9 | 537 | |
0cbf2b82 | 538 | #ifndef DISABLE_EVENT |
f69979cf JH |
539 | if (verify_event(&tls_out, cert, depth, dn, |
540 | &dummy_called, &optional, US"DANE")) | |
541 | return 0; /* reject, with peercert set */ | |
83b27293 JH |
542 | #endif |
543 | ||
f2f2c91b | 544 | if (preverify_ok == 1) |
53a7196b | 545 | tls_out.dane_verified = |
e5cccda9 | 546 | tls_out.certificate_verified = TRUE; |
f2f2c91b JH |
547 | else |
548 | { | |
549 | int err = X509_STORE_CTX_get_error(x509ctx); | |
550 | DEBUG(D_tls) | |
551 | debug_printf(" - err %d '%s'\n", err, X509_verify_cert_error_string(err)); | |
3c51463e | 552 | if (err == X509_V_ERR_APPLICATION_VERIFICATION) |
f2f2c91b JH |
553 | preverify_ok = 1; |
554 | } | |
555 | return preverify_ok; | |
e5cccda9 | 556 | } |
53a7196b JH |
557 | |
558 | #endif /*EXPERIMENTAL_DANE*/ | |
e5cccda9 | 559 | |
059ec3d9 PH |
560 | |
561 | /************************************************* | |
562 | * Information callback * | |
563 | *************************************************/ | |
564 | ||
565 | /* The SSL library functions call this from time to time to indicate what they | |
7be682ca PP |
566 | are doing. We copy the string to the debugging output when TLS debugging has |
567 | been requested. | |
059ec3d9 PH |
568 | |
569 | Arguments: | |
570 | s the SSL connection | |
571 | where | |
572 | ret | |
573 | ||
574 | Returns: nothing | |
575 | */ | |
576 | ||
577 | static void | |
578 | info_callback(SSL *s, int where, int ret) | |
579 | { | |
580 | where = where; | |
581 | ret = ret; | |
582 | DEBUG(D_tls) debug_printf("SSL info: %s\n", SSL_state_string_long(s)); | |
583 | } | |
584 | ||
585 | ||
586 | ||
587 | /************************************************* | |
588 | * Initialize for DH * | |
589 | *************************************************/ | |
590 | ||
591 | /* If dhparam is set, expand it, and load up the parameters for DH encryption. | |
592 | ||
593 | Arguments: | |
038597d2 | 594 | sctx The current SSL CTX (inbound or outbound) |
a799883d | 595 | dhparam DH parameter file or fixed parameter identity string |
7199e1ee | 596 | host connected host, if client; NULL if server |
059ec3d9 PH |
597 | |
598 | Returns: TRUE if OK (nothing to set up, or setup worked) | |
599 | */ | |
600 | ||
601 | static BOOL | |
b8b1b5cb | 602 | init_dh(SSL_CTX *sctx, uschar *dhparam, const host_item *host) |
059ec3d9 | 603 | { |
059ec3d9 PH |
604 | BIO *bio; |
605 | DH *dh; | |
606 | uschar *dhexpanded; | |
a799883d | 607 | const char *pem; |
059ec3d9 PH |
608 | |
609 | if (!expand_check(dhparam, US"tls_dhparam", &dhexpanded)) | |
610 | return FALSE; | |
611 | ||
0df4ab80 | 612 | if (!dhexpanded || !*dhexpanded) |
a799883d | 613 | bio = BIO_new_mem_buf(CS std_dh_prime_default(), -1); |
a799883d | 614 | else if (dhexpanded[0] == '/') |
059ec3d9 | 615 | { |
0df4ab80 | 616 | if (!(bio = BIO_new_file(CS dhexpanded, "r"))) |
059ec3d9 | 617 | { |
7199e1ee | 618 | tls_error(string_sprintf("could not read dhparams file %s", dhexpanded), |
a799883d PP |
619 | host, US strerror(errno)); |
620 | return FALSE; | |
059ec3d9 | 621 | } |
a799883d PP |
622 | } |
623 | else | |
624 | { | |
625 | if (Ustrcmp(dhexpanded, "none") == 0) | |
059ec3d9 | 626 | { |
a799883d PP |
627 | DEBUG(D_tls) debug_printf("Requested no DH parameters.\n"); |
628 | return TRUE; | |
059ec3d9 | 629 | } |
a799883d | 630 | |
0df4ab80 | 631 | if (!(pem = std_dh_prime_named(dhexpanded))) |
a799883d PP |
632 | { |
633 | tls_error(string_sprintf("Unknown standard DH prime \"%s\"", dhexpanded), | |
634 | host, US strerror(errno)); | |
635 | return FALSE; | |
636 | } | |
637 | bio = BIO_new_mem_buf(CS pem, -1); | |
638 | } | |
639 | ||
0df4ab80 | 640 | if (!(dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL))) |
a799883d | 641 | { |
059ec3d9 | 642 | BIO_free(bio); |
a799883d PP |
643 | tls_error(string_sprintf("Could not read tls_dhparams \"%s\"", dhexpanded), |
644 | host, NULL); | |
645 | return FALSE; | |
646 | } | |
647 | ||
648 | /* Even if it is larger, we silently return success rather than cause things | |
649 | * to fail out, so that a too-large DH will not knock out all TLS; it's a | |
650 | * debatable choice. */ | |
651 | if ((8*DH_size(dh)) > tls_dh_max_bits) | |
652 | { | |
653 | DEBUG(D_tls) | |
654 | debug_printf("dhparams file %d bits, is > tls_dh_max_bits limit of %d", | |
655 | 8*DH_size(dh), tls_dh_max_bits); | |
656 | } | |
657 | else | |
658 | { | |
659 | SSL_CTX_set_tmp_dh(sctx, dh); | |
660 | DEBUG(D_tls) | |
661 | debug_printf("Diffie-Hellman initialized from %s with %d-bit prime\n", | |
662 | dhexpanded ? dhexpanded : US"default", 8*DH_size(dh)); | |
059ec3d9 PH |
663 | } |
664 | ||
a799883d PP |
665 | DH_free(dh); |
666 | BIO_free(bio); | |
667 | ||
668 | return TRUE; | |
059ec3d9 PH |
669 | } |
670 | ||
671 | ||
672 | ||
673 | ||
038597d2 PP |
674 | /************************************************* |
675 | * Initialize for ECDH * | |
676 | *************************************************/ | |
677 | ||
678 | /* Load parameters for ECDH encryption. | |
679 | ||
680 | For now, we stick to NIST P-256 because: it's simple and easy to configure; | |
681 | it avoids any patent issues that might bite redistributors; despite events in | |
682 | the news and concerns over curve choices, we're not cryptographers, we're not | |
683 | pretending to be, and this is "good enough" to be better than no support, | |
684 | protecting against most adversaries. Given another year or two, there might | |
685 | be sufficient clarity about a "right" way forward to let us make an informed | |
686 | decision, instead of a knee-jerk reaction. | |
687 | ||
688 | Longer-term, we should look at supporting both various named curves and | |
689 | external files generated with "openssl ecparam", much as we do for init_dh(). | |
690 | We should also support "none" as a value, to explicitly avoid initialisation. | |
691 | ||
692 | Patches welcome. | |
693 | ||
694 | Arguments: | |
695 | sctx The current SSL CTX (inbound or outbound) | |
696 | host connected host, if client; NULL if server | |
697 | ||
698 | Returns: TRUE if OK (nothing to set up, or setup worked) | |
699 | */ | |
700 | ||
701 | static BOOL | |
10ca4f1c | 702 | init_ecdh(SSL_CTX * sctx, host_item * host) |
038597d2 | 703 | { |
63f0dbe0 JH |
704 | #ifdef OPENSSL_NO_ECDH |
705 | return TRUE; | |
706 | #else | |
707 | ||
10ca4f1c JH |
708 | EC_KEY * ecdh; |
709 | uschar * exp_curve; | |
710 | int nid; | |
711 | BOOL rv; | |
712 | ||
038597d2 PP |
713 | if (host) /* No ECDH setup for clients, only for servers */ |
714 | return TRUE; | |
715 | ||
10ca4f1c | 716 | # ifndef EXIM_HAVE_ECDH |
038597d2 PP |
717 | DEBUG(D_tls) |
718 | debug_printf("No OpenSSL API to define ECDH parameters, skipping\n"); | |
719 | return TRUE; | |
038597d2 | 720 | # else |
10ca4f1c JH |
721 | |
722 | if (!expand_check(tls_eccurve, US"tls_eccurve", &exp_curve)) | |
723 | return FALSE; | |
724 | if (!exp_curve || !*exp_curve) | |
725 | return TRUE; | |
726 | ||
727 | # ifdef EXIM_HAVE_OPENSSL_ECDH_AUTO | |
728 | /* check if new enough library to support auto ECDH temp key parameter selection */ | |
729 | if (Ustrcmp(exp_curve, "auto") == 0) | |
038597d2 | 730 | { |
10ca4f1c JH |
731 | DEBUG(D_tls) debug_printf( |
732 | "ECDH temp key parameter settings: OpenSSL 1.2+ autoselection\n"); | |
733 | SSL_CTX_set_ecdh_auto(sctx, 1); | |
734 | return TRUE; | |
735 | } | |
736 | # endif | |
038597d2 | 737 | |
10ca4f1c JH |
738 | DEBUG(D_tls) debug_printf("ECDH: curve '%s'\n", exp_curve); |
739 | if ( (nid = OBJ_sn2nid (CCS exp_curve)) == NID_undef | |
740 | # ifdef EXIM_HAVE_OPENSSL_EC_NIST2NID | |
741 | && (nid = EC_curve_nist2nid(CCS exp_curve)) == NID_undef | |
742 | # endif | |
743 | ) | |
744 | { | |
745 | tls_error(string_sprintf("Unknown curve name tls_eccurve '%s'", | |
746 | exp_curve), | |
747 | host, NULL); | |
748 | return FALSE; | |
749 | } | |
038597d2 | 750 | |
10ca4f1c JH |
751 | if (!(ecdh = EC_KEY_new_by_curve_name(nid))) |
752 | { | |
aa7751be | 753 | tls_error(US"Unable to create ec curve", host, NULL); |
10ca4f1c | 754 | return FALSE; |
038597d2 | 755 | } |
10ca4f1c JH |
756 | |
757 | /* The "tmp" in the name here refers to setting a temporary key | |
758 | not to the stability of the interface. */ | |
759 | ||
760 | if ((rv = SSL_CTX_set_tmp_ecdh(sctx, ecdh) == 0)) | |
761 | tls_error(string_sprintf("Error enabling '%s' curve", exp_curve), host, NULL); | |
762 | else | |
763 | DEBUG(D_tls) debug_printf("ECDH: enabled '%s' curve\n", exp_curve); | |
764 | ||
765 | EC_KEY_free(ecdh); | |
766 | return !rv; | |
767 | ||
768 | # endif /*EXIM_HAVE_ECDH*/ | |
769 | #endif /*OPENSSL_NO_ECDH*/ | |
038597d2 PP |
770 | } |
771 | ||
772 | ||
773 | ||
774 | ||
f2de3a33 | 775 | #ifndef DISABLE_OCSP |
3f7eeb86 PP |
776 | /************************************************* |
777 | * Load OCSP information into state * | |
778 | *************************************************/ | |
779 | ||
f5d78688 | 780 | /* Called to load the server OCSP response from the given file into memory, once |
3f7eeb86 PP |
781 | caller has determined this is needed. Checks validity. Debugs a message |
782 | if invalid. | |
783 | ||
784 | ASSUMES: single response, for single cert. | |
785 | ||
786 | Arguments: | |
787 | sctx the SSL_CTX* to update | |
788 | cbinfo various parts of session state | |
789 | expanded the filename putatively holding an OCSP response | |
790 | ||
791 | */ | |
792 | ||
793 | static void | |
f5d78688 | 794 | ocsp_load_response(SSL_CTX *sctx, tls_ext_ctx_cb *cbinfo, const uschar *expanded) |
3f7eeb86 PP |
795 | { |
796 | BIO *bio; | |
797 | OCSP_RESPONSE *resp; | |
798 | OCSP_BASICRESP *basic_response; | |
799 | OCSP_SINGLERESP *single_response; | |
800 | ASN1_GENERALIZEDTIME *rev, *thisupd, *nextupd; | |
801 | X509_STORE *store; | |
802 | unsigned long verify_flags; | |
803 | int status, reason, i; | |
804 | ||
f5d78688 JH |
805 | cbinfo->u_ocsp.server.file_expanded = string_copy(expanded); |
806 | if (cbinfo->u_ocsp.server.response) | |
3f7eeb86 | 807 | { |
f5d78688 JH |
808 | OCSP_RESPONSE_free(cbinfo->u_ocsp.server.response); |
809 | cbinfo->u_ocsp.server.response = NULL; | |
3f7eeb86 PP |
810 | } |
811 | ||
f5d78688 | 812 | bio = BIO_new_file(CS cbinfo->u_ocsp.server.file_expanded, "rb"); |
3f7eeb86 PP |
813 | if (!bio) |
814 | { | |
815 | DEBUG(D_tls) debug_printf("Failed to open OCSP response file \"%s\"\n", | |
f5d78688 | 816 | cbinfo->u_ocsp.server.file_expanded); |
3f7eeb86 PP |
817 | return; |
818 | } | |
819 | ||
820 | resp = d2i_OCSP_RESPONSE_bio(bio, NULL); | |
821 | BIO_free(bio); | |
822 | if (!resp) | |
823 | { | |
824 | DEBUG(D_tls) debug_printf("Error reading OCSP response.\n"); | |
825 | return; | |
826 | } | |
827 | ||
828 | status = OCSP_response_status(resp); | |
829 | if (status != OCSP_RESPONSE_STATUS_SUCCESSFUL) | |
830 | { | |
831 | DEBUG(D_tls) debug_printf("OCSP response not valid: %s (%d)\n", | |
832 | OCSP_response_status_str(status), status); | |
f5d78688 | 833 | goto bad; |
3f7eeb86 PP |
834 | } |
835 | ||
836 | basic_response = OCSP_response_get1_basic(resp); | |
837 | if (!basic_response) | |
838 | { | |
839 | DEBUG(D_tls) | |
840 | debug_printf("OCSP response parse error: unable to extract basic response.\n"); | |
f5d78688 | 841 | goto bad; |
3f7eeb86 PP |
842 | } |
843 | ||
844 | store = SSL_CTX_get_cert_store(sctx); | |
845 | verify_flags = OCSP_NOVERIFY; /* check sigs, but not purpose */ | |
846 | ||
847 | /* May need to expose ability to adjust those flags? | |
848 | OCSP_NOSIGS OCSP_NOVERIFY OCSP_NOCHAIN OCSP_NOCHECKS OCSP_NOEXPLICIT | |
849 | OCSP_TRUSTOTHER OCSP_NOINTERN */ | |
850 | ||
851 | i = OCSP_basic_verify(basic_response, NULL, store, verify_flags); | |
852 | if (i <= 0) | |
853 | { | |
854 | DEBUG(D_tls) { | |
855 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
856 | debug_printf("OCSP response verify failure: %s\n", US ssl_errstring); | |
f5d78688 JH |
857 | } |
858 | goto bad; | |
3f7eeb86 PP |
859 | } |
860 | ||
861 | /* Here's the simplifying assumption: there's only one response, for the | |
862 | one certificate we use, and nothing for anything else in a chain. If this | |
863 | proves false, we need to extract a cert id from our issued cert | |
864 | (tls_certificate) and use that for OCSP_resp_find_status() (which finds the | |
865 | right cert in the stack and then calls OCSP_single_get0_status()). | |
866 | ||
867 | I'm hoping to avoid reworking a bunch more of how we handle state here. */ | |
868 | single_response = OCSP_resp_get0(basic_response, 0); | |
869 | if (!single_response) | |
870 | { | |
871 | DEBUG(D_tls) | |
872 | debug_printf("Unable to get first response from OCSP basic response.\n"); | |
f5d78688 | 873 | goto bad; |
3f7eeb86 PP |
874 | } |
875 | ||
876 | status = OCSP_single_get0_status(single_response, &reason, &rev, &thisupd, &nextupd); | |
f5d78688 | 877 | if (status != V_OCSP_CERTSTATUS_GOOD) |
3f7eeb86 | 878 | { |
f5d78688 JH |
879 | DEBUG(D_tls) debug_printf("OCSP response bad cert status: %s (%d) %s (%d)\n", |
880 | OCSP_cert_status_str(status), status, | |
881 | OCSP_crl_reason_str(reason), reason); | |
882 | goto bad; | |
3f7eeb86 PP |
883 | } |
884 | ||
885 | if (!OCSP_check_validity(thisupd, nextupd, EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE)) | |
886 | { | |
887 | DEBUG(D_tls) debug_printf("OCSP status invalid times.\n"); | |
f5d78688 | 888 | goto bad; |
3f7eeb86 PP |
889 | } |
890 | ||
f5d78688 | 891 | supply_response: |
018058b2 | 892 | cbinfo->u_ocsp.server.response = resp; |
f5d78688 JH |
893 | return; |
894 | ||
895 | bad: | |
018058b2 JH |
896 | if (running_in_test_harness) |
897 | { | |
898 | extern char ** environ; | |
899 | uschar ** p; | |
900 | for (p = USS environ; *p != NULL; p++) | |
901 | if (Ustrncmp(*p, "EXIM_TESTHARNESS_DISABLE_OCSPVALIDITYCHECK", 42) == 0) | |
902 | { | |
903 | DEBUG(D_tls) debug_printf("Supplying known bad OCSP response\n"); | |
904 | goto supply_response; | |
905 | } | |
906 | } | |
f5d78688 | 907 | return; |
3f7eeb86 | 908 | } |
f2de3a33 | 909 | #endif /*!DISABLE_OCSP*/ |
3f7eeb86 PP |
910 | |
911 | ||
912 | ||
913 | ||
7be682ca PP |
914 | /************************************************* |
915 | * Expand key and cert file specs * | |
916 | *************************************************/ | |
917 | ||
f5d78688 | 918 | /* Called once during tls_init and possibly again during TLS setup, for a |
7be682ca PP |
919 | new context, if Server Name Indication was used and tls_sni was seen in |
920 | the certificate string. | |
921 | ||
922 | Arguments: | |
923 | sctx the SSL_CTX* to update | |
924 | cbinfo various parts of session state | |
925 | ||
926 | Returns: OK/DEFER/FAIL | |
927 | */ | |
928 | ||
929 | static int | |
3f7eeb86 | 930 | tls_expand_session_files(SSL_CTX *sctx, tls_ext_ctx_cb *cbinfo) |
7be682ca PP |
931 | { |
932 | uschar *expanded; | |
933 | ||
934 | if (cbinfo->certificate == NULL) | |
935 | return OK; | |
936 | ||
d9b2312b JH |
937 | if (Ustrstr(cbinfo->certificate, US"tls_sni") || |
938 | Ustrstr(cbinfo->certificate, US"tls_in_sni") || | |
939 | Ustrstr(cbinfo->certificate, US"tls_out_sni") | |
940 | ) | |
7be682ca PP |
941 | reexpand_tls_files_for_sni = TRUE; |
942 | ||
943 | if (!expand_check(cbinfo->certificate, US"tls_certificate", &expanded)) | |
944 | return DEFER; | |
945 | ||
946 | if (expanded != NULL) | |
947 | { | |
948 | DEBUG(D_tls) debug_printf("tls_certificate file %s\n", expanded); | |
949 | if (!SSL_CTX_use_certificate_chain_file(sctx, CS expanded)) | |
950 | return tls_error(string_sprintf( | |
951 | "SSL_CTX_use_certificate_chain_file file=%s", expanded), | |
952 | cbinfo->host, NULL); | |
953 | } | |
954 | ||
955 | if (cbinfo->privatekey != NULL && | |
956 | !expand_check(cbinfo->privatekey, US"tls_privatekey", &expanded)) | |
957 | return DEFER; | |
958 | ||
959 | /* If expansion was forced to fail, key_expanded will be NULL. If the result | |
960 | of the expansion is an empty string, ignore it also, and assume the private | |
961 | key is in the same file as the certificate. */ | |
962 | ||
f40d5be3 | 963 | if (expanded && *expanded) |
7be682ca PP |
964 | { |
965 | DEBUG(D_tls) debug_printf("tls_privatekey file %s\n", expanded); | |
966 | if (!SSL_CTX_use_PrivateKey_file(sctx, CS expanded, SSL_FILETYPE_PEM)) | |
967 | return tls_error(string_sprintf( | |
968 | "SSL_CTX_use_PrivateKey_file file=%s", expanded), cbinfo->host, NULL); | |
969 | } | |
970 | ||
f2de3a33 | 971 | #ifndef DISABLE_OCSP |
f40d5be3 | 972 | if (cbinfo->is_server && cbinfo->u_ocsp.server.file) |
3f7eeb86 | 973 | { |
f5d78688 | 974 | if (!expand_check(cbinfo->u_ocsp.server.file, US"tls_ocsp_file", &expanded)) |
3f7eeb86 PP |
975 | return DEFER; |
976 | ||
f40d5be3 | 977 | if (expanded && *expanded) |
3f7eeb86 PP |
978 | { |
979 | DEBUG(D_tls) debug_printf("tls_ocsp_file %s\n", expanded); | |
f40d5be3 JH |
980 | if ( cbinfo->u_ocsp.server.file_expanded |
981 | && (Ustrcmp(expanded, cbinfo->u_ocsp.server.file_expanded) == 0)) | |
3f7eeb86 | 982 | { |
f40d5be3 JH |
983 | DEBUG(D_tls) debug_printf(" - value unchanged, using existing values\n"); |
984 | } | |
985 | else | |
986 | { | |
987 | ocsp_load_response(sctx, cbinfo, expanded); | |
3f7eeb86 PP |
988 | } |
989 | } | |
990 | } | |
991 | #endif | |
992 | ||
7be682ca PP |
993 | return OK; |
994 | } | |
995 | ||
996 | ||
997 | ||
998 | ||
999 | /************************************************* | |
1000 | * Callback to handle SNI * | |
1001 | *************************************************/ | |
1002 | ||
1003 | /* Called when acting as server during the TLS session setup if a Server Name | |
1004 | Indication extension was sent by the client. | |
1005 | ||
1006 | API documentation is OpenSSL s_server.c implementation. | |
1007 | ||
1008 | Arguments: | |
1009 | s SSL* of the current session | |
1010 | ad unknown (part of OpenSSL API) (unused) | |
1011 | arg Callback of "our" registered data | |
1012 | ||
1013 | Returns: SSL_TLSEXT_ERR_{OK,ALERT_WARNING,ALERT_FATAL,NOACK} | |
1014 | */ | |
1015 | ||
3bcbbbe2 | 1016 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
7be682ca PP |
1017 | static int |
1018 | tls_servername_cb(SSL *s, int *ad ARG_UNUSED, void *arg) | |
1019 | { | |
1020 | const char *servername = SSL_get_servername(s, TLSEXT_NAMETYPE_host_name); | |
3f7eeb86 | 1021 | tls_ext_ctx_cb *cbinfo = (tls_ext_ctx_cb *) arg; |
7be682ca | 1022 | int rc; |
3f0945ff | 1023 | int old_pool = store_pool; |
7be682ca PP |
1024 | |
1025 | if (!servername) | |
1026 | return SSL_TLSEXT_ERR_OK; | |
1027 | ||
3f0945ff | 1028 | DEBUG(D_tls) debug_printf("Received TLS SNI \"%s\"%s\n", servername, |
7be682ca PP |
1029 | reexpand_tls_files_for_sni ? "" : " (unused for certificate selection)"); |
1030 | ||
1031 | /* Make the extension value available for expansion */ | |
3f0945ff | 1032 | store_pool = POOL_PERM; |
817d9f57 | 1033 | tls_in.sni = string_copy(US servername); |
3f0945ff | 1034 | store_pool = old_pool; |
7be682ca PP |
1035 | |
1036 | if (!reexpand_tls_files_for_sni) | |
1037 | return SSL_TLSEXT_ERR_OK; | |
1038 | ||
1039 | /* Can't find an SSL_CTX_clone() or equivalent, so we do it manually; | |
1040 | not confident that memcpy wouldn't break some internal reference counting. | |
1041 | Especially since there's a references struct member, which would be off. */ | |
1042 | ||
0df4ab80 | 1043 | if (!(server_sni = SSL_CTX_new(SSLv23_server_method()))) |
7be682ca PP |
1044 | { |
1045 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
1046 | DEBUG(D_tls) debug_printf("SSL_CTX_new() failed: %s\n", ssl_errstring); | |
1047 | return SSL_TLSEXT_ERR_NOACK; | |
1048 | } | |
1049 | ||
1050 | /* Not sure how many of these are actually needed, since SSL object | |
1051 | already exists. Might even need this selfsame callback, for reneg? */ | |
1052 | ||
817d9f57 JH |
1053 | SSL_CTX_set_info_callback(server_sni, SSL_CTX_get_info_callback(server_ctx)); |
1054 | SSL_CTX_set_mode(server_sni, SSL_CTX_get_mode(server_ctx)); | |
1055 | SSL_CTX_set_options(server_sni, SSL_CTX_get_options(server_ctx)); | |
1056 | SSL_CTX_set_timeout(server_sni, SSL_CTX_get_timeout(server_ctx)); | |
1057 | SSL_CTX_set_tlsext_servername_callback(server_sni, tls_servername_cb); | |
1058 | SSL_CTX_set_tlsext_servername_arg(server_sni, cbinfo); | |
038597d2 PP |
1059 | |
1060 | if ( !init_dh(server_sni, cbinfo->dhparam, NULL) | |
1061 | || !init_ecdh(server_sni, NULL) | |
1062 | ) | |
1063 | return SSL_TLSEXT_ERR_NOACK; | |
1064 | ||
7be682ca | 1065 | if (cbinfo->server_cipher_list) |
817d9f57 | 1066 | SSL_CTX_set_cipher_list(server_sni, CS cbinfo->server_cipher_list); |
f2de3a33 | 1067 | #ifndef DISABLE_OCSP |
f5d78688 | 1068 | if (cbinfo->u_ocsp.server.file) |
3f7eeb86 | 1069 | { |
f5d78688 | 1070 | SSL_CTX_set_tlsext_status_cb(server_sni, tls_server_stapling_cb); |
14c7b357 | 1071 | SSL_CTX_set_tlsext_status_arg(server_sni, cbinfo); |
3f7eeb86 PP |
1072 | } |
1073 | #endif | |
7be682ca | 1074 | |
983207c1 | 1075 | rc = setup_certs(server_sni, tls_verify_certificates, tls_crl, NULL, FALSE, verify_callback_server); |
7be682ca PP |
1076 | if (rc != OK) return SSL_TLSEXT_ERR_NOACK; |
1077 | ||
3f7eeb86 PP |
1078 | /* do this after setup_certs, because this can require the certs for verifying |
1079 | OCSP information. */ | |
038597d2 | 1080 | if ((rc = tls_expand_session_files(server_sni, cbinfo)) != OK) |
0df4ab80 | 1081 | return SSL_TLSEXT_ERR_NOACK; |
a799883d | 1082 | |
7be682ca | 1083 | DEBUG(D_tls) debug_printf("Switching SSL context.\n"); |
817d9f57 | 1084 | SSL_set_SSL_CTX(s, server_sni); |
7be682ca PP |
1085 | |
1086 | return SSL_TLSEXT_ERR_OK; | |
1087 | } | |
3bcbbbe2 | 1088 | #endif /* EXIM_HAVE_OPENSSL_TLSEXT */ |
7be682ca PP |
1089 | |
1090 | ||
1091 | ||
1092 | ||
f2de3a33 | 1093 | #ifndef DISABLE_OCSP |
f5d78688 | 1094 | |
3f7eeb86 PP |
1095 | /************************************************* |
1096 | * Callback to handle OCSP Stapling * | |
1097 | *************************************************/ | |
1098 | ||
1099 | /* Called when acting as server during the TLS session setup if the client | |
1100 | requests OCSP information with a Certificate Status Request. | |
1101 | ||
1102 | Documentation via openssl s_server.c and the Apache patch from the OpenSSL | |
1103 | project. | |
1104 | ||
1105 | */ | |
1106 | ||
1107 | static int | |
f5d78688 | 1108 | tls_server_stapling_cb(SSL *s, void *arg) |
3f7eeb86 PP |
1109 | { |
1110 | const tls_ext_ctx_cb *cbinfo = (tls_ext_ctx_cb *) arg; | |
1111 | uschar *response_der; | |
1112 | int response_der_len; | |
1113 | ||
af4a1bca | 1114 | DEBUG(D_tls) |
b3ef41c9 | 1115 | debug_printf("Received TLS status request (OCSP stapling); %s response\n", |
f5d78688 JH |
1116 | cbinfo->u_ocsp.server.response ? "have" : "lack"); |
1117 | ||
44662487 | 1118 | tls_in.ocsp = OCSP_NOT_RESP; |
f5d78688 | 1119 | if (!cbinfo->u_ocsp.server.response) |
3f7eeb86 PP |
1120 | return SSL_TLSEXT_ERR_NOACK; |
1121 | ||
1122 | response_der = NULL; | |
44662487 JH |
1123 | response_der_len = i2d_OCSP_RESPONSE(cbinfo->u_ocsp.server.response, |
1124 | &response_der); | |
3f7eeb86 PP |
1125 | if (response_der_len <= 0) |
1126 | return SSL_TLSEXT_ERR_NOACK; | |
1127 | ||
5e55c7a9 | 1128 | SSL_set_tlsext_status_ocsp_resp(server_ssl, response_der, response_der_len); |
44662487 | 1129 | tls_in.ocsp = OCSP_VFIED; |
3f7eeb86 PP |
1130 | return SSL_TLSEXT_ERR_OK; |
1131 | } | |
1132 | ||
3f7eeb86 | 1133 | |
f5d78688 JH |
1134 | static void |
1135 | time_print(BIO * bp, const char * str, ASN1_GENERALIZEDTIME * time) | |
1136 | { | |
1137 | BIO_printf(bp, "\t%s: ", str); | |
1138 | ASN1_GENERALIZEDTIME_print(bp, time); | |
1139 | BIO_puts(bp, "\n"); | |
1140 | } | |
1141 | ||
1142 | static int | |
1143 | tls_client_stapling_cb(SSL *s, void *arg) | |
1144 | { | |
1145 | tls_ext_ctx_cb * cbinfo = arg; | |
1146 | const unsigned char * p; | |
1147 | int len; | |
1148 | OCSP_RESPONSE * rsp; | |
1149 | OCSP_BASICRESP * bs; | |
1150 | int i; | |
1151 | ||
1152 | DEBUG(D_tls) debug_printf("Received TLS status response (OCSP stapling):"); | |
1153 | len = SSL_get_tlsext_status_ocsp_resp(s, &p); | |
1154 | if(!p) | |
1155 | { | |
44662487 | 1156 | /* Expect this when we requested ocsp but got none */ |
6c6d6e48 | 1157 | if (cbinfo->u_ocsp.client.verify_required && LOGGING(tls_cipher)) |
44662487 | 1158 | log_write(0, LOG_MAIN, "Received TLS status callback, null content"); |
f5d78688 JH |
1159 | else |
1160 | DEBUG(D_tls) debug_printf(" null\n"); | |
44662487 | 1161 | return cbinfo->u_ocsp.client.verify_required ? 0 : 1; |
f5d78688 | 1162 | } |
018058b2 | 1163 | |
f5d78688 JH |
1164 | if(!(rsp = d2i_OCSP_RESPONSE(NULL, &p, len))) |
1165 | { | |
018058b2 | 1166 | tls_out.ocsp = OCSP_FAILED; |
6c6d6e48 | 1167 | if (LOGGING(tls_cipher)) |
1eca31ca | 1168 | log_write(0, LOG_MAIN, "Received TLS cert status response, parse error"); |
f5d78688 JH |
1169 | else |
1170 | DEBUG(D_tls) debug_printf(" parse error\n"); | |
1171 | return 0; | |
1172 | } | |
1173 | ||
1174 | if(!(bs = OCSP_response_get1_basic(rsp))) | |
1175 | { | |
018058b2 | 1176 | tls_out.ocsp = OCSP_FAILED; |
6c6d6e48 | 1177 | if (LOGGING(tls_cipher)) |
1eca31ca | 1178 | log_write(0, LOG_MAIN, "Received TLS cert status response, error parsing response"); |
f5d78688 JH |
1179 | else |
1180 | DEBUG(D_tls) debug_printf(" error parsing response\n"); | |
1181 | OCSP_RESPONSE_free(rsp); | |
1182 | return 0; | |
1183 | } | |
1184 | ||
1185 | /* We'd check the nonce here if we'd put one in the request. */ | |
1186 | /* However that would defeat cacheability on the server so we don't. */ | |
1187 | ||
f5d78688 JH |
1188 | /* This section of code reworked from OpenSSL apps source; |
1189 | The OpenSSL Project retains copyright: | |
1190 | Copyright (c) 1999 The OpenSSL Project. All rights reserved. | |
1191 | */ | |
1192 | { | |
1193 | BIO * bp = NULL; | |
f5d78688 JH |
1194 | int status, reason; |
1195 | ASN1_GENERALIZEDTIME *rev, *thisupd, *nextupd; | |
1196 | ||
1197 | DEBUG(D_tls) bp = BIO_new_fp(stderr, BIO_NOCLOSE); | |
1198 | ||
1199 | /*OCSP_RESPONSE_print(bp, rsp, 0); extreme debug: stapling content */ | |
1200 | ||
1201 | /* Use the chain that verified the server cert to verify the stapled info */ | |
1202 | /* DEBUG(D_tls) x509_store_dump_cert_s_names(cbinfo->u_ocsp.client.verify_store); */ | |
1203 | ||
44662487 JH |
1204 | if ((i = OCSP_basic_verify(bs, NULL, |
1205 | cbinfo->u_ocsp.client.verify_store, 0)) <= 0) | |
f5d78688 | 1206 | { |
018058b2 | 1207 | tls_out.ocsp = OCSP_FAILED; |
6c6d6e48 | 1208 | if (LOGGING(tls_cipher)) |
1eca31ca | 1209 | log_write(0, LOG_MAIN, "Received TLS cert status response, itself unverifiable"); |
f5d78688 JH |
1210 | BIO_printf(bp, "OCSP response verify failure\n"); |
1211 | ERR_print_errors(bp); | |
c8dfb21d | 1212 | goto failed; |
f5d78688 JH |
1213 | } |
1214 | ||
1215 | BIO_printf(bp, "OCSP response well-formed and signed OK\n"); | |
1216 | ||
c8dfb21d JH |
1217 | /*XXX So we have a good stapled OCSP status. How do we know |
1218 | it is for the cert of interest? OpenSSL 1.1.0 has a routine | |
1219 | OCSP_resp_find_status() which matches on a cert id, which presumably | |
1220 | we should use. Making an id needs OCSP_cert_id_new(), which takes | |
1221 | issuerName, issuerKey, serialNumber. Are they all in the cert? | |
1222 | ||
1223 | For now, carry on blindly accepting the resp. */ | |
1224 | ||
f5d78688 | 1225 | { |
f5d78688 JH |
1226 | OCSP_SINGLERESP * single; |
1227 | ||
c8dfb21d JH |
1228 | #ifdef EXIM_HAVE_OCSP_RESP_COUNT |
1229 | if (OCSP_resp_count(bs) != 1) | |
1230 | #else | |
1231 | STACK_OF(OCSP_SINGLERESP) * sresp = bs->tbsResponseData->responses; | |
f5d78688 | 1232 | if (sk_OCSP_SINGLERESP_num(sresp) != 1) |
c8dfb21d | 1233 | #endif |
f5d78688 | 1234 | { |
018058b2 | 1235 | tls_out.ocsp = OCSP_FAILED; |
44662487 JH |
1236 | log_write(0, LOG_MAIN, "OCSP stapling " |
1237 | "with multiple responses not handled"); | |
c8dfb21d | 1238 | goto failed; |
f5d78688 JH |
1239 | } |
1240 | single = OCSP_resp_get0(bs, 0); | |
44662487 JH |
1241 | status = OCSP_single_get0_status(single, &reason, &rev, |
1242 | &thisupd, &nextupd); | |
f5d78688 JH |
1243 | } |
1244 | ||
f5d78688 JH |
1245 | DEBUG(D_tls) time_print(bp, "This OCSP Update", thisupd); |
1246 | DEBUG(D_tls) if(nextupd) time_print(bp, "Next OCSP Update", nextupd); | |
44662487 JH |
1247 | if (!OCSP_check_validity(thisupd, nextupd, |
1248 | EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE)) | |
f5d78688 | 1249 | { |
018058b2 | 1250 | tls_out.ocsp = OCSP_FAILED; |
f5d78688 JH |
1251 | DEBUG(D_tls) ERR_print_errors(bp); |
1252 | log_write(0, LOG_MAIN, "Server OSCP dates invalid"); | |
f5d78688 | 1253 | } |
44662487 | 1254 | else |
f5d78688 | 1255 | { |
44662487 JH |
1256 | DEBUG(D_tls) BIO_printf(bp, "Certificate status: %s\n", |
1257 | OCSP_cert_status_str(status)); | |
1258 | switch(status) | |
1259 | { | |
1260 | case V_OCSP_CERTSTATUS_GOOD: | |
44662487 | 1261 | tls_out.ocsp = OCSP_VFIED; |
018058b2 | 1262 | i = 1; |
c8dfb21d | 1263 | goto good; |
44662487 | 1264 | case V_OCSP_CERTSTATUS_REVOKED: |
018058b2 | 1265 | tls_out.ocsp = OCSP_FAILED; |
44662487 JH |
1266 | log_write(0, LOG_MAIN, "Server certificate revoked%s%s", |
1267 | reason != -1 ? "; reason: " : "", | |
1268 | reason != -1 ? OCSP_crl_reason_str(reason) : ""); | |
1269 | DEBUG(D_tls) time_print(bp, "Revocation Time", rev); | |
44662487 JH |
1270 | break; |
1271 | default: | |
018058b2 | 1272 | tls_out.ocsp = OCSP_FAILED; |
44662487 JH |
1273 | log_write(0, LOG_MAIN, |
1274 | "Server certificate status unknown, in OCSP stapling"); | |
44662487 JH |
1275 | break; |
1276 | } | |
f5d78688 | 1277 | } |
c8dfb21d JH |
1278 | failed: |
1279 | i = cbinfo->u_ocsp.client.verify_required ? 0 : 1; | |
1280 | good: | |
f5d78688 JH |
1281 | BIO_free(bp); |
1282 | } | |
1283 | ||
1284 | OCSP_RESPONSE_free(rsp); | |
1285 | return i; | |
1286 | } | |
f2de3a33 | 1287 | #endif /*!DISABLE_OCSP*/ |
3f7eeb86 PP |
1288 | |
1289 | ||
059ec3d9 PH |
1290 | /************************************************* |
1291 | * Initialize for TLS * | |
1292 | *************************************************/ | |
1293 | ||
e51c7be2 JH |
1294 | /* Called from both server and client code, to do preliminary initialization |
1295 | of the library. We allocate and return a context structure. | |
059ec3d9 PH |
1296 | |
1297 | Arguments: | |
946ecbe0 | 1298 | ctxp returned SSL context |
059ec3d9 PH |
1299 | host connected host, if client; NULL if server |
1300 | dhparam DH parameter file | |
1301 | certificate certificate file | |
1302 | privatekey private key | |
f5d78688 | 1303 | ocsp_file file of stapling info (server); flag for require ocsp (client) |
059ec3d9 | 1304 | addr address if client; NULL if server (for some randomness) |
946ecbe0 | 1305 | cbp place to put allocated callback context |
059ec3d9 PH |
1306 | |
1307 | Returns: OK/DEFER/FAIL | |
1308 | */ | |
1309 | ||
1310 | static int | |
817d9f57 | 1311 | tls_init(SSL_CTX **ctxp, host_item *host, uschar *dhparam, uschar *certificate, |
3f7eeb86 | 1312 | uschar *privatekey, |
f2de3a33 | 1313 | #ifndef DISABLE_OCSP |
3f7eeb86 PP |
1314 | uschar *ocsp_file, |
1315 | #endif | |
817d9f57 | 1316 | address_item *addr, tls_ext_ctx_cb ** cbp) |
059ec3d9 | 1317 | { |
77bb000f | 1318 | long init_options; |
7be682ca | 1319 | int rc; |
77bb000f | 1320 | BOOL okay; |
a7538db1 | 1321 | tls_ext_ctx_cb * cbinfo; |
7be682ca PP |
1322 | |
1323 | cbinfo = store_malloc(sizeof(tls_ext_ctx_cb)); | |
1324 | cbinfo->certificate = certificate; | |
1325 | cbinfo->privatekey = privatekey; | |
f2de3a33 | 1326 | #ifndef DISABLE_OCSP |
f5d78688 JH |
1327 | if ((cbinfo->is_server = host==NULL)) |
1328 | { | |
1329 | cbinfo->u_ocsp.server.file = ocsp_file; | |
1330 | cbinfo->u_ocsp.server.file_expanded = NULL; | |
1331 | cbinfo->u_ocsp.server.response = NULL; | |
1332 | } | |
1333 | else | |
1334 | cbinfo->u_ocsp.client.verify_store = NULL; | |
3f7eeb86 | 1335 | #endif |
7be682ca | 1336 | cbinfo->dhparam = dhparam; |
0df4ab80 | 1337 | cbinfo->server_cipher_list = NULL; |
7be682ca | 1338 | cbinfo->host = host; |
0cbf2b82 | 1339 | #ifndef DISABLE_EVENT |
a7538db1 JH |
1340 | cbinfo->event_action = NULL; |
1341 | #endif | |
77bb000f | 1342 | |
059ec3d9 PH |
1343 | SSL_load_error_strings(); /* basic set up */ |
1344 | OpenSSL_add_ssl_algorithms(); | |
1345 | ||
c8dfb21d | 1346 | #ifdef EXIM_HAVE_SHA256 |
77bb000f | 1347 | /* SHA256 is becoming ever more popular. This makes sure it gets added to the |
a0475b69 TK |
1348 | list of available digests. */ |
1349 | EVP_add_digest(EVP_sha256()); | |
cf1ef1a9 | 1350 | #endif |
a0475b69 | 1351 | |
f0f5a555 PP |
1352 | /* Create a context. |
1353 | The OpenSSL docs in 1.0.1b have not been updated to clarify TLS variant | |
1354 | negotiation in the different methods; as far as I can tell, the only | |
1355 | *_{server,client}_method which allows negotiation is SSLv23, which exists even | |
1356 | when OpenSSL is built without SSLv2 support. | |
1357 | By disabling with openssl_options, we can let admins re-enable with the | |
1358 | existing knob. */ | |
059ec3d9 | 1359 | |
c8dfb21d | 1360 | *ctxp = SSL_CTX_new(host ? SSLv23_client_method() : SSLv23_server_method()); |
059ec3d9 | 1361 | |
c8dfb21d | 1362 | if (!*ctxp) return tls_error(US"SSL_CTX_new", host, NULL); |
059ec3d9 PH |
1363 | |
1364 | /* It turns out that we need to seed the random number generator this early in | |
1365 | order to get the full complement of ciphers to work. It took me roughly a day | |
1366 | of work to discover this by experiment. | |
1367 | ||
1368 | On systems that have /dev/urandom, SSL may automatically seed itself from | |
1369 | there. Otherwise, we have to make something up as best we can. Double check | |
1370 | afterwards. */ | |
1371 | ||
1372 | if (!RAND_status()) | |
1373 | { | |
1374 | randstuff r; | |
9e3331ea | 1375 | gettimeofday(&r.tv, NULL); |
059ec3d9 PH |
1376 | r.p = getpid(); |
1377 | ||
1378 | RAND_seed((uschar *)(&r), sizeof(r)); | |
1379 | RAND_seed((uschar *)big_buffer, big_buffer_size); | |
1380 | if (addr != NULL) RAND_seed((uschar *)addr, sizeof(addr)); | |
1381 | ||
1382 | if (!RAND_status()) | |
7199e1ee | 1383 | return tls_error(US"RAND_status", host, |
5ca6d115 | 1384 | US"unable to seed random number generator"); |
059ec3d9 PH |
1385 | } |
1386 | ||
1387 | /* Set up the information callback, which outputs if debugging is at a suitable | |
1388 | level. */ | |
1389 | ||
f69979cf | 1390 | DEBUG(D_tls) SSL_CTX_set_info_callback(*ctxp, (void (*)())info_callback); |
059ec3d9 | 1391 | |
c80c5570 | 1392 | /* Automatically re-try reads/writes after renegotiation. */ |
817d9f57 | 1393 | (void) SSL_CTX_set_mode(*ctxp, SSL_MODE_AUTO_RETRY); |
c80c5570 | 1394 | |
77bb000f PP |
1395 | /* Apply administrator-supplied work-arounds. |
1396 | Historically we applied just one requested option, | |
1397 | SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS, but when bug 994 requested a second, we | |
1398 | moved to an administrator-controlled list of options to specify and | |
1399 | grandfathered in the first one as the default value for "openssl_options". | |
059ec3d9 | 1400 | |
77bb000f PP |
1401 | No OpenSSL version number checks: the options we accept depend upon the |
1402 | availability of the option value macros from OpenSSL. */ | |
059ec3d9 | 1403 | |
77bb000f PP |
1404 | okay = tls_openssl_options_parse(openssl_options, &init_options); |
1405 | if (!okay) | |
73a46702 | 1406 | return tls_error(US"openssl_options parsing failed", host, NULL); |
77bb000f PP |
1407 | |
1408 | if (init_options) | |
1409 | { | |
1410 | DEBUG(D_tls) debug_printf("setting SSL CTX options: %#lx\n", init_options); | |
817d9f57 | 1411 | if (!(SSL_CTX_set_options(*ctxp, init_options))) |
77bb000f PP |
1412 | return tls_error(string_sprintf( |
1413 | "SSL_CTX_set_option(%#lx)", init_options), host, NULL); | |
1414 | } | |
1415 | else | |
1416 | DEBUG(D_tls) debug_printf("no SSL CTX options to set\n"); | |
059ec3d9 PH |
1417 | |
1418 | /* Initialize with DH parameters if supplied */ | |
10ca4f1c | 1419 | /* Initialize ECDH temp key parameter selection */ |
059ec3d9 | 1420 | |
038597d2 PP |
1421 | if ( !init_dh(*ctxp, dhparam, host) |
1422 | || !init_ecdh(*ctxp, host) | |
1423 | ) | |
1424 | return DEFER; | |
059ec3d9 | 1425 | |
3f7eeb86 | 1426 | /* Set up certificate and key (and perhaps OCSP info) */ |
059ec3d9 | 1427 | |
817d9f57 | 1428 | rc = tls_expand_session_files(*ctxp, cbinfo); |
7be682ca | 1429 | if (rc != OK) return rc; |
c91535f3 | 1430 | |
7be682ca | 1431 | /* If we need to handle SNI, do so */ |
3bcbbbe2 | 1432 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
f5d78688 | 1433 | if (host == NULL) /* server */ |
3f0945ff | 1434 | { |
f2de3a33 | 1435 | # ifndef DISABLE_OCSP |
f5d78688 | 1436 | /* We check u_ocsp.server.file, not server.response, because we care about if |
3f7eeb86 PP |
1437 | the option exists, not what the current expansion might be, as SNI might |
1438 | change the certificate and OCSP file in use between now and the time the | |
1439 | callback is invoked. */ | |
f5d78688 | 1440 | if (cbinfo->u_ocsp.server.file) |
3f7eeb86 | 1441 | { |
f5d78688 | 1442 | SSL_CTX_set_tlsext_status_cb(server_ctx, tls_server_stapling_cb); |
5e55c7a9 | 1443 | SSL_CTX_set_tlsext_status_arg(server_ctx, cbinfo); |
3f7eeb86 | 1444 | } |
f5d78688 | 1445 | # endif |
3f0945ff PP |
1446 | /* We always do this, so that $tls_sni is available even if not used in |
1447 | tls_certificate */ | |
817d9f57 JH |
1448 | SSL_CTX_set_tlsext_servername_callback(*ctxp, tls_servername_cb); |
1449 | SSL_CTX_set_tlsext_servername_arg(*ctxp, cbinfo); | |
3f0945ff | 1450 | } |
f2de3a33 | 1451 | # ifndef DISABLE_OCSP |
f5d78688 JH |
1452 | else /* client */ |
1453 | if(ocsp_file) /* wanting stapling */ | |
1454 | { | |
1455 | if (!(cbinfo->u_ocsp.client.verify_store = X509_STORE_new())) | |
1456 | { | |
1457 | DEBUG(D_tls) debug_printf("failed to create store for stapling verify\n"); | |
1458 | return FAIL; | |
1459 | } | |
1460 | SSL_CTX_set_tlsext_status_cb(*ctxp, tls_client_stapling_cb); | |
1461 | SSL_CTX_set_tlsext_status_arg(*ctxp, cbinfo); | |
1462 | } | |
1463 | # endif | |
7be682ca | 1464 | #endif |
059ec3d9 | 1465 | |
e51c7be2 | 1466 | cbinfo->verify_cert_hostnames = NULL; |
e51c7be2 | 1467 | |
c8dfb21d | 1468 | #ifdef EXIM_HAVE_EPHEM_RSA_KEX |
059ec3d9 | 1469 | /* Set up the RSA callback */ |
817d9f57 | 1470 | SSL_CTX_set_tmp_rsa_callback(*ctxp, rsa_callback); |
c8dfb21d | 1471 | #endif |
059ec3d9 PH |
1472 | |
1473 | /* Finally, set the timeout, and we are done */ | |
1474 | ||
817d9f57 | 1475 | SSL_CTX_set_timeout(*ctxp, ssl_session_timeout); |
059ec3d9 | 1476 | DEBUG(D_tls) debug_printf("Initialized TLS\n"); |
7be682ca | 1477 | |
817d9f57 | 1478 | *cbp = cbinfo; |
7be682ca | 1479 | |
059ec3d9 PH |
1480 | return OK; |
1481 | } | |
1482 | ||
1483 | ||
1484 | ||
1485 | ||
1486 | /************************************************* | |
1487 | * Get name of cipher in use * | |
1488 | *************************************************/ | |
1489 | ||
817d9f57 | 1490 | /* |
059ec3d9 | 1491 | Argument: pointer to an SSL structure for the connection |
817d9f57 JH |
1492 | buffer to use for answer |
1493 | size of buffer | |
1494 | pointer to number of bits for cipher | |
059ec3d9 PH |
1495 | Returns: nothing |
1496 | */ | |
1497 | ||
1498 | static void | |
817d9f57 | 1499 | construct_cipher_name(SSL *ssl, uschar *cipherbuf, int bsize, int *bits) |
059ec3d9 | 1500 | { |
57b3a7f5 PP |
1501 | /* With OpenSSL 1.0.0a, this needs to be const but the documentation doesn't |
1502 | yet reflect that. It should be a safe change anyway, even 0.9.8 versions have | |
1503 | the accessor functions use const in the prototype. */ | |
1504 | const SSL_CIPHER *c; | |
d9784128 | 1505 | const uschar *ver; |
059ec3d9 | 1506 | |
d9784128 | 1507 | ver = (const uschar *)SSL_get_version(ssl); |
059ec3d9 | 1508 | |
57b3a7f5 | 1509 | c = (const SSL_CIPHER *) SSL_get_current_cipher(ssl); |
817d9f57 | 1510 | SSL_CIPHER_get_bits(c, bits); |
059ec3d9 | 1511 | |
817d9f57 JH |
1512 | string_format(cipherbuf, bsize, "%s:%s:%u", ver, |
1513 | SSL_CIPHER_get_name(c), *bits); | |
059ec3d9 PH |
1514 | |
1515 | DEBUG(D_tls) debug_printf("Cipher: %s\n", cipherbuf); | |
1516 | } | |
1517 | ||
1518 | ||
f69979cf JH |
1519 | static void |
1520 | peer_cert(SSL * ssl, tls_support * tlsp, uschar * peerdn, unsigned bsize) | |
1521 | { | |
1522 | /*XXX we might consider a list-of-certs variable for the cert chain. | |
1523 | SSL_get_peer_cert_chain(SSL*). We'd need a new variable type and support | |
1524 | in list-handling functions, also consider the difference between the entire | |
1525 | chain and the elements sent by the peer. */ | |
1526 | ||
1527 | /* Will have already noted peercert on a verify fail; possibly not the leaf */ | |
1528 | if (!tlsp->peercert) | |
1529 | tlsp->peercert = SSL_get_peer_certificate(ssl); | |
1530 | /* Beware anonymous ciphers which lead to server_cert being NULL */ | |
1531 | if (tlsp->peercert) | |
1532 | { | |
1533 | X509_NAME_oneline(X509_get_subject_name(tlsp->peercert), CS peerdn, bsize); | |
1534 | peerdn[bsize-1] = '\0'; | |
1535 | tlsp->peerdn = peerdn; /*XXX a static buffer... */ | |
1536 | } | |
1537 | else | |
1538 | tlsp->peerdn = NULL; | |
1539 | } | |
1540 | ||
1541 | ||
059ec3d9 PH |
1542 | |
1543 | ||
1544 | ||
1545 | /************************************************* | |
1546 | * Set up for verifying certificates * | |
1547 | *************************************************/ | |
1548 | ||
1549 | /* Called by both client and server startup | |
1550 | ||
1551 | Arguments: | |
7be682ca | 1552 | sctx SSL_CTX* to initialise |
059ec3d9 PH |
1553 | certs certs file or NULL |
1554 | crl CRL file or NULL | |
1555 | host NULL in a server; the remote host in a client | |
1556 | optional TRUE if called from a server for a host in tls_try_verify_hosts; | |
1557 | otherwise passed as FALSE | |
983207c1 | 1558 | cert_vfy_cb Callback function for certificate verification |
059ec3d9 PH |
1559 | |
1560 | Returns: OK/DEFER/FAIL | |
1561 | */ | |
1562 | ||
1563 | static int | |
983207c1 JH |
1564 | setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host, BOOL optional, |
1565 | int (*cert_vfy_cb)(int, X509_STORE_CTX *) ) | |
059ec3d9 PH |
1566 | { |
1567 | uschar *expcerts, *expcrl; | |
1568 | ||
1569 | if (!expand_check(certs, US"tls_verify_certificates", &expcerts)) | |
1570 | return DEFER; | |
1571 | ||
10a831a3 | 1572 | if (expcerts && *expcerts) |
059ec3d9 | 1573 | { |
10a831a3 JH |
1574 | /* Tell the library to use its compiled-in location for the system default |
1575 | CA bundle. Then add the ones specified in the config, if any. */ | |
cb1d7830 | 1576 | |
10a831a3 JH |
1577 | if (!SSL_CTX_set_default_verify_paths(sctx)) |
1578 | return tls_error(US"SSL_CTX_set_default_verify_paths", host, NULL); | |
1579 | ||
1580 | if (Ustrcmp(expcerts, "system") != 0) | |
059ec3d9 | 1581 | { |
cb1d7830 JH |
1582 | struct stat statbuf; |
1583 | ||
cb1d7830 JH |
1584 | if (Ustat(expcerts, &statbuf) < 0) |
1585 | { | |
1586 | log_write(0, LOG_MAIN|LOG_PANIC, | |
1587 | "failed to stat %s for certificates", expcerts); | |
1588 | return DEFER; | |
1589 | } | |
059ec3d9 | 1590 | else |
059ec3d9 | 1591 | { |
cb1d7830 JH |
1592 | uschar *file, *dir; |
1593 | if ((statbuf.st_mode & S_IFMT) == S_IFDIR) | |
1594 | { file = NULL; dir = expcerts; } | |
1595 | else | |
1596 | { file = expcerts; dir = NULL; } | |
1597 | ||
1598 | /* If a certificate file is empty, the next function fails with an | |
1599 | unhelpful error message. If we skip it, we get the correct behaviour (no | |
1600 | certificates are recognized, but the error message is still misleading (it | |
1601 | says no certificate was supplied.) But this is better. */ | |
1602 | ||
f2f2c91b JH |
1603 | if ( (!file || statbuf.st_size > 0) |
1604 | && !SSL_CTX_load_verify_locations(sctx, CS file, CS dir)) | |
cb1d7830 JH |
1605 | return tls_error(US"SSL_CTX_load_verify_locations", host, NULL); |
1606 | ||
1607 | /* Load the list of CAs for which we will accept certs, for sending | |
1608 | to the client. This is only for the one-file tls_verify_certificates | |
1609 | variant. | |
1610 | If a list isn't loaded into the server, but | |
1611 | some verify locations are set, the server end appears to make | |
1612 | a wildcard reqest for client certs. | |
10a831a3 | 1613 | Meanwhile, the client library as default behaviour *ignores* the list |
cb1d7830 JH |
1614 | we send over the wire - see man SSL_CTX_set_client_cert_cb. |
1615 | Because of this, and that the dir variant is likely only used for | |
1616 | the public-CA bundle (not for a private CA), not worth fixing. | |
1617 | */ | |
f2f2c91b | 1618 | if (file) |
cb1d7830 JH |
1619 | { |
1620 | STACK_OF(X509_NAME) * names = SSL_load_client_CA_file(CS file); | |
f2f2c91b JH |
1621 | |
1622 | DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", | |
cb1d7830 JH |
1623 | sk_X509_NAME_num(names)); |
1624 | SSL_CTX_set_client_CA_list(sctx, names); | |
1625 | } | |
059ec3d9 PH |
1626 | } |
1627 | } | |
1628 | ||
1629 | /* Handle a certificate revocation list. */ | |
1630 | ||
10a831a3 | 1631 | #if OPENSSL_VERSION_NUMBER > 0x00907000L |
059ec3d9 | 1632 | |
8b417f2c | 1633 | /* This bit of code is now the version supplied by Lars Mainka. (I have |
10a831a3 | 1634 | merely reformatted it into the Exim code style.) |
8b417f2c | 1635 | |
10a831a3 JH |
1636 | "From here I changed the code to add support for multiple crl's |
1637 | in pem format in one file or to support hashed directory entries in | |
1638 | pem format instead of a file. This method now uses the library function | |
1639 | X509_STORE_load_locations to add the CRL location to the SSL context. | |
1640 | OpenSSL will then handle the verify against CA certs and CRLs by | |
1641 | itself in the verify callback." */ | |
8b417f2c | 1642 | |
059ec3d9 | 1643 | if (!expand_check(crl, US"tls_crl", &expcrl)) return DEFER; |
10a831a3 | 1644 | if (expcrl && *expcrl) |
059ec3d9 | 1645 | { |
8b417f2c PH |
1646 | struct stat statbufcrl; |
1647 | if (Ustat(expcrl, &statbufcrl) < 0) | |
1648 | { | |
1649 | log_write(0, LOG_MAIN|LOG_PANIC, | |
1650 | "failed to stat %s for certificates revocation lists", expcrl); | |
1651 | return DEFER; | |
1652 | } | |
1653 | else | |
059ec3d9 | 1654 | { |
8b417f2c PH |
1655 | /* is it a file or directory? */ |
1656 | uschar *file, *dir; | |
7be682ca | 1657 | X509_STORE *cvstore = SSL_CTX_get_cert_store(sctx); |
8b417f2c | 1658 | if ((statbufcrl.st_mode & S_IFMT) == S_IFDIR) |
059ec3d9 | 1659 | { |
8b417f2c PH |
1660 | file = NULL; |
1661 | dir = expcrl; | |
1662 | DEBUG(D_tls) debug_printf("SSL CRL value is a directory %s\n", dir); | |
059ec3d9 PH |
1663 | } |
1664 | else | |
1665 | { | |
8b417f2c PH |
1666 | file = expcrl; |
1667 | dir = NULL; | |
1668 | DEBUG(D_tls) debug_printf("SSL CRL value is a file %s\n", file); | |
059ec3d9 | 1669 | } |
8b417f2c | 1670 | if (X509_STORE_load_locations(cvstore, CS file, CS dir) == 0) |
7199e1ee | 1671 | return tls_error(US"X509_STORE_load_locations", host, NULL); |
8b417f2c PH |
1672 | |
1673 | /* setting the flags to check against the complete crl chain */ | |
1674 | ||
1675 | X509_STORE_set_flags(cvstore, | |
1676 | X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL); | |
059ec3d9 | 1677 | } |
059ec3d9 PH |
1678 | } |
1679 | ||
10a831a3 | 1680 | #endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */ |
059ec3d9 PH |
1681 | |
1682 | /* If verification is optional, don't fail if no certificate */ | |
1683 | ||
7be682ca | 1684 | SSL_CTX_set_verify(sctx, |
059ec3d9 | 1685 | SSL_VERIFY_PEER | (optional? 0 : SSL_VERIFY_FAIL_IF_NO_PEER_CERT), |
983207c1 | 1686 | cert_vfy_cb); |
059ec3d9 PH |
1687 | } |
1688 | ||
1689 | return OK; | |
1690 | } | |
1691 | ||
1692 | ||
1693 | ||
1694 | /************************************************* | |
1695 | * Start a TLS session in a server * | |
1696 | *************************************************/ | |
1697 | ||
1698 | /* This is called when Exim is running as a server, after having received | |
1699 | the STARTTLS command. It must respond to that command, and then negotiate | |
1700 | a TLS session. | |
1701 | ||
1702 | Arguments: | |
1703 | require_ciphers allowed ciphers | |
1704 | ||
1705 | Returns: OK on success | |
1706 | DEFER for errors before the start of the negotiation | |
1707 | FAIL for errors during the negotation; the server can't | |
1708 | continue running. | |
1709 | */ | |
1710 | ||
1711 | int | |
17c76198 | 1712 | tls_server_start(const uschar *require_ciphers) |
059ec3d9 PH |
1713 | { |
1714 | int rc; | |
1715 | uschar *expciphers; | |
7be682ca | 1716 | tls_ext_ctx_cb *cbinfo; |
f69979cf | 1717 | static uschar peerdn[256]; |
817d9f57 | 1718 | static uschar cipherbuf[256]; |
059ec3d9 PH |
1719 | |
1720 | /* Check for previous activation */ | |
1721 | ||
817d9f57 | 1722 | if (tls_in.active >= 0) |
059ec3d9 | 1723 | { |
5ca6d115 | 1724 | tls_error(US"STARTTLS received after TLS started", NULL, US""); |
059ec3d9 PH |
1725 | smtp_printf("554 Already in TLS\r\n"); |
1726 | return FAIL; | |
1727 | } | |
1728 | ||
1729 | /* Initialize the SSL library. If it fails, it will already have logged | |
1730 | the error. */ | |
1731 | ||
817d9f57 | 1732 | rc = tls_init(&server_ctx, NULL, tls_dhparam, tls_certificate, tls_privatekey, |
f2de3a33 | 1733 | #ifndef DISABLE_OCSP |
3f7eeb86 PP |
1734 | tls_ocsp_file, |
1735 | #endif | |
817d9f57 | 1736 | NULL, &server_static_cbinfo); |
059ec3d9 | 1737 | if (rc != OK) return rc; |
817d9f57 | 1738 | cbinfo = server_static_cbinfo; |
059ec3d9 PH |
1739 | |
1740 | if (!expand_check(require_ciphers, US"tls_require_ciphers", &expciphers)) | |
1741 | return FAIL; | |
1742 | ||
1743 | /* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they | |
17c76198 PP |
1744 | were historically separated by underscores. So that I can use either form in my |
1745 | tests, and also for general convenience, we turn underscores into hyphens here. | |
1746 | */ | |
059ec3d9 PH |
1747 | |
1748 | if (expciphers != NULL) | |
1749 | { | |
1750 | uschar *s = expciphers; | |
1751 | while (*s != 0) { if (*s == '_') *s = '-'; s++; } | |
1752 | DEBUG(D_tls) debug_printf("required ciphers: %s\n", expciphers); | |
817d9f57 | 1753 | if (!SSL_CTX_set_cipher_list(server_ctx, CS expciphers)) |
7199e1ee | 1754 | return tls_error(US"SSL_CTX_set_cipher_list", NULL, NULL); |
7be682ca | 1755 | cbinfo->server_cipher_list = expciphers; |
059ec3d9 PH |
1756 | } |
1757 | ||
1758 | /* If this is a host for which certificate verification is mandatory or | |
1759 | optional, set up appropriately. */ | |
1760 | ||
817d9f57 | 1761 | tls_in.certificate_verified = FALSE; |
53a7196b JH |
1762 | #ifdef EXPERIMENTAL_DANE |
1763 | tls_in.dane_verified = FALSE; | |
1764 | #endif | |
a2ff477a | 1765 | server_verify_callback_called = FALSE; |
059ec3d9 PH |
1766 | |
1767 | if (verify_check_host(&tls_verify_hosts) == OK) | |
1768 | { | |
983207c1 JH |
1769 | rc = setup_certs(server_ctx, tls_verify_certificates, tls_crl, NULL, |
1770 | FALSE, verify_callback_server); | |
059ec3d9 | 1771 | if (rc != OK) return rc; |
a2ff477a | 1772 | server_verify_optional = FALSE; |
059ec3d9 PH |
1773 | } |
1774 | else if (verify_check_host(&tls_try_verify_hosts) == OK) | |
1775 | { | |
983207c1 JH |
1776 | rc = setup_certs(server_ctx, tls_verify_certificates, tls_crl, NULL, |
1777 | TRUE, verify_callback_server); | |
059ec3d9 | 1778 | if (rc != OK) return rc; |
a2ff477a | 1779 | server_verify_optional = TRUE; |
059ec3d9 PH |
1780 | } |
1781 | ||
1782 | /* Prepare for new connection */ | |
1783 | ||
817d9f57 | 1784 | if ((server_ssl = SSL_new(server_ctx)) == NULL) return tls_error(US"SSL_new", NULL, NULL); |
da3ad30d PP |
1785 | |
1786 | /* Warning: we used to SSL_clear(ssl) here, it was removed. | |
1787 | * | |
1788 | * With the SSL_clear(), we get strange interoperability bugs with | |
1789 | * OpenSSL 1.0.1b and TLS1.1/1.2. It looks as though this may be a bug in | |
1790 | * OpenSSL itself, as a clear should not lead to inability to follow protocols. | |
1791 | * | |
1792 | * The SSL_clear() call is to let an existing SSL* be reused, typically after | |
1793 | * session shutdown. In this case, we have a brand new object and there's no | |
1794 | * obvious reason to immediately clear it. I'm guessing that this was | |
1795 | * originally added because of incomplete initialisation which the clear fixed, | |
1796 | * in some historic release. | |
1797 | */ | |
059ec3d9 PH |
1798 | |
1799 | /* Set context and tell client to go ahead, except in the case of TLS startup | |
1800 | on connection, where outputting anything now upsets the clients and tends to | |
1801 | make them disconnect. We need to have an explicit fflush() here, to force out | |
1802 | the response. Other smtp_printf() calls do not need it, because in non-TLS | |
1803 | mode, the fflush() happens when smtp_getc() is called. */ | |
1804 | ||
817d9f57 JH |
1805 | SSL_set_session_id_context(server_ssl, sid_ctx, Ustrlen(sid_ctx)); |
1806 | if (!tls_in.on_connect) | |
059ec3d9 PH |
1807 | { |
1808 | smtp_printf("220 TLS go ahead\r\n"); | |
1809 | fflush(smtp_out); | |
1810 | } | |
1811 | ||
1812 | /* Now negotiate the TLS session. We put our own timer on it, since it seems | |
1813 | that the OpenSSL library doesn't. */ | |
1814 | ||
817d9f57 JH |
1815 | SSL_set_wfd(server_ssl, fileno(smtp_out)); |
1816 | SSL_set_rfd(server_ssl, fileno(smtp_in)); | |
1817 | SSL_set_accept_state(server_ssl); | |
059ec3d9 PH |
1818 | |
1819 | DEBUG(D_tls) debug_printf("Calling SSL_accept\n"); | |
1820 | ||
1821 | sigalrm_seen = FALSE; | |
1822 | if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout); | |
817d9f57 | 1823 | rc = SSL_accept(server_ssl); |
059ec3d9 PH |
1824 | alarm(0); |
1825 | ||
1826 | if (rc <= 0) | |
1827 | { | |
7199e1ee | 1828 | tls_error(US"SSL_accept", NULL, sigalrm_seen ? US"timed out" : NULL); |
77bb000f PP |
1829 | if (ERR_get_error() == 0) |
1830 | log_write(0, LOG_MAIN, | |
a053d125 | 1831 | "TLS client disconnected cleanly (rejected our certificate?)"); |
059ec3d9 PH |
1832 | return FAIL; |
1833 | } | |
1834 | ||
1835 | DEBUG(D_tls) debug_printf("SSL_accept was successful\n"); | |
1836 | ||
1837 | /* TLS has been set up. Adjust the input functions to read via TLS, | |
1838 | and initialize things. */ | |
1839 | ||
f69979cf JH |
1840 | peer_cert(server_ssl, &tls_in, peerdn, sizeof(peerdn)); |
1841 | ||
817d9f57 JH |
1842 | construct_cipher_name(server_ssl, cipherbuf, sizeof(cipherbuf), &tls_in.bits); |
1843 | tls_in.cipher = cipherbuf; | |
059ec3d9 PH |
1844 | |
1845 | DEBUG(D_tls) | |
1846 | { | |
1847 | uschar buf[2048]; | |
817d9f57 | 1848 | if (SSL_get_shared_ciphers(server_ssl, CS buf, sizeof(buf)) != NULL) |
059ec3d9 PH |
1849 | debug_printf("Shared ciphers: %s\n", buf); |
1850 | } | |
1851 | ||
9d1c15ef JH |
1852 | /* Record the certificate we presented */ |
1853 | { | |
1854 | X509 * crt = SSL_get_certificate(server_ssl); | |
1855 | tls_in.ourcert = crt ? X509_dup(crt) : NULL; | |
1856 | } | |
059ec3d9 | 1857 | |
817d9f57 JH |
1858 | /* Only used by the server-side tls (tls_in), including tls_getc. |
1859 | Client-side (tls_out) reads (seem to?) go via | |
1860 | smtp_read_response()/ip_recv(). | |
1861 | Hence no need to duplicate for _in and _out. | |
1862 | */ | |
059ec3d9 PH |
1863 | ssl_xfer_buffer = store_malloc(ssl_xfer_buffer_size); |
1864 | ssl_xfer_buffer_lwm = ssl_xfer_buffer_hwm = 0; | |
1865 | ssl_xfer_eof = ssl_xfer_error = 0; | |
1866 | ||
1867 | receive_getc = tls_getc; | |
1868 | receive_ungetc = tls_ungetc; | |
1869 | receive_feof = tls_feof; | |
1870 | receive_ferror = tls_ferror; | |
58eb016e | 1871 | receive_smtp_buffered = tls_smtp_buffered; |
059ec3d9 | 1872 | |
817d9f57 | 1873 | tls_in.active = fileno(smtp_out); |
059ec3d9 PH |
1874 | return OK; |
1875 | } | |
1876 | ||
1877 | ||
1878 | ||
1879 | ||
043b1248 JH |
1880 | static int |
1881 | tls_client_basic_ctx_init(SSL_CTX * ctx, | |
01a4a5c5 | 1882 | host_item * host, smtp_transport_options_block * ob, tls_ext_ctx_cb * cbinfo |
043b1248 JH |
1883 | ) |
1884 | { | |
1885 | int rc; | |
94431adb | 1886 | /* stick to the old behaviour for compatibility if tls_verify_certificates is |
043b1248 JH |
1887 | set but both tls_verify_hosts and tls_try_verify_hosts is not set. Check only |
1888 | the specified host patterns if one of them is defined */ | |
1889 | ||
610ff438 JH |
1890 | if ( ( !ob->tls_verify_hosts |
1891 | && (!ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts) | |
1892 | ) | |
5130845b | 1893 | || (verify_check_given_host(&ob->tls_verify_hosts, host) == OK) |
aa2a70ba | 1894 | ) |
043b1248 | 1895 | client_verify_optional = FALSE; |
5130845b | 1896 | else if (verify_check_given_host(&ob->tls_try_verify_hosts, host) == OK) |
aa2a70ba JH |
1897 | client_verify_optional = TRUE; |
1898 | else | |
1899 | return OK; | |
1900 | ||
1901 | if ((rc = setup_certs(ctx, ob->tls_verify_certificates, | |
1902 | ob->tls_crl, host, client_verify_optional, verify_callback_client)) != OK) | |
1903 | return rc; | |
043b1248 | 1904 | |
5130845b | 1905 | if (verify_check_given_host(&ob->tls_verify_cert_hostnames, host) == OK) |
043b1248 | 1906 | { |
4af0d74a | 1907 | cbinfo->verify_cert_hostnames = |
8c5d388a | 1908 | #ifdef SUPPORT_I18N |
4af0d74a JH |
1909 | string_domain_utf8_to_alabel(host->name, NULL); |
1910 | #else | |
1911 | host->name; | |
1912 | #endif | |
aa2a70ba JH |
1913 | DEBUG(D_tls) debug_printf("Cert hostname to check: \"%s\"\n", |
1914 | cbinfo->verify_cert_hostnames); | |
043b1248 | 1915 | } |
043b1248 JH |
1916 | return OK; |
1917 | } | |
059ec3d9 | 1918 | |
fde080a4 JH |
1919 | |
1920 | #ifdef EXPERIMENTAL_DANE | |
fde080a4 JH |
1921 | static int |
1922 | dane_tlsa_load(SSL * ssl, host_item * host, dns_answer * dnsa) | |
1923 | { | |
1924 | dns_record * rr; | |
1925 | dns_scan dnss; | |
1926 | const char * hostnames[2] = { CS host->name, NULL }; | |
1927 | int found = 0; | |
1928 | ||
1929 | if (DANESSL_init(ssl, NULL, hostnames) != 1) | |
1930 | return tls_error(US"hostnames load", host, NULL); | |
1931 | ||
1932 | for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); | |
1933 | rr; | |
1934 | rr = dns_next_rr(dnsa, &dnss, RESET_NEXT) | |
1935 | ) if (rr->type == T_TLSA) | |
1936 | { | |
1937 | uschar * p = rr->data; | |
1938 | uint8_t usage, selector, mtype; | |
1939 | const char * mdname; | |
1940 | ||
fde080a4 | 1941 | usage = *p++; |
133d2546 JH |
1942 | |
1943 | /* Only DANE-TA(2) and DANE-EE(3) are supported */ | |
1944 | if (usage != 2 && usage != 3) continue; | |
1945 | ||
fde080a4 JH |
1946 | selector = *p++; |
1947 | mtype = *p++; | |
1948 | ||
1949 | switch (mtype) | |
1950 | { | |
133d2546 JH |
1951 | default: continue; /* Only match-types 0, 1, 2 are supported */ |
1952 | case 0: mdname = NULL; break; | |
1953 | case 1: mdname = "sha256"; break; | |
1954 | case 2: mdname = "sha512"; break; | |
fde080a4 JH |
1955 | } |
1956 | ||
133d2546 | 1957 | found++; |
fde080a4 JH |
1958 | switch (DANESSL_add_tlsa(ssl, usage, selector, mdname, p, rr->size - 3)) |
1959 | { | |
1960 | default: | |
1961 | case 0: /* action not taken */ | |
1962 | return tls_error(US"tlsa load", host, NULL); | |
1963 | case 1: break; | |
1964 | } | |
594706ea JH |
1965 | |
1966 | tls_out.tlsa_usage |= 1<<usage; | |
fde080a4 JH |
1967 | } |
1968 | ||
1969 | if (found) | |
1970 | return OK; | |
1971 | ||
133d2546 | 1972 | log_write(0, LOG_MAIN, "DANE error: No usable TLSA records"); |
6ebd79ec | 1973 | return DEFER; |
fde080a4 JH |
1974 | } |
1975 | #endif /*EXPERIMENTAL_DANE*/ | |
1976 | ||
1977 | ||
1978 | ||
059ec3d9 PH |
1979 | /************************************************* |
1980 | * Start a TLS session in a client * | |
1981 | *************************************************/ | |
1982 | ||
1983 | /* Called from the smtp transport after STARTTLS has been accepted. | |
1984 | ||
1985 | Argument: | |
1986 | fd the fd of the connection | |
1987 | host connected host (for messages) | |
83da1223 | 1988 | addr the first address |
a7538db1 | 1989 | tb transport (always smtp) |
0e66b3b6 | 1990 | tlsa_dnsa tlsa lookup, if DANE, else null |
059ec3d9 PH |
1991 | |
1992 | Returns: OK on success | |
1993 | FAIL otherwise - note that tls_error() will not give DEFER | |
1994 | because this is not a server | |
1995 | */ | |
1996 | ||
1997 | int | |
f5d78688 | 1998 | tls_client_start(int fd, host_item *host, address_item *addr, |
0e66b3b6 JH |
1999 | transport_instance *tb |
2000 | #ifdef EXPERIMENTAL_DANE | |
2001 | , dns_answer * tlsa_dnsa | |
2002 | #endif | |
2003 | ) | |
059ec3d9 | 2004 | { |
a7538db1 JH |
2005 | smtp_transport_options_block * ob = |
2006 | (smtp_transport_options_block *)tb->options_block; | |
f69979cf | 2007 | static uschar peerdn[256]; |
868f5672 | 2008 | uschar * expciphers; |
059ec3d9 | 2009 | int rc; |
817d9f57 | 2010 | static uschar cipherbuf[256]; |
043b1248 JH |
2011 | |
2012 | #ifndef DISABLE_OCSP | |
043b1248 | 2013 | BOOL request_ocsp = FALSE; |
6634ac8d | 2014 | BOOL require_ocsp = FALSE; |
043b1248 | 2015 | #endif |
043b1248 JH |
2016 | |
2017 | #ifdef EXPERIMENTAL_DANE | |
594706ea | 2018 | tls_out.tlsa_usage = 0; |
043b1248 JH |
2019 | #endif |
2020 | ||
f2de3a33 | 2021 | #ifndef DISABLE_OCSP |
043b1248 | 2022 | { |
4f59c424 JH |
2023 | # ifdef EXPERIMENTAL_DANE |
2024 | if ( tlsa_dnsa | |
2025 | && ob->hosts_request_ocsp[0] == '*' | |
2026 | && ob->hosts_request_ocsp[1] == '\0' | |
2027 | ) | |
2028 | { | |
2029 | /* Unchanged from default. Use a safer one under DANE */ | |
2030 | request_ocsp = TRUE; | |
2031 | ob->hosts_request_ocsp = US"${if or { {= {0}{$tls_out_tlsa_usage}} " | |
2032 | " {= {4}{$tls_out_tlsa_usage}} } " | |
2033 | " {*}{}}"; | |
2034 | } | |
2035 | # endif | |
2036 | ||
5130845b JH |
2037 | if ((require_ocsp = |
2038 | verify_check_given_host(&ob->hosts_require_ocsp, host) == OK)) | |
fca41d5a JH |
2039 | request_ocsp = TRUE; |
2040 | else | |
fca41d5a | 2041 | # ifdef EXPERIMENTAL_DANE |
4f59c424 | 2042 | if (!request_ocsp) |
fca41d5a | 2043 | # endif |
5130845b JH |
2044 | request_ocsp = |
2045 | verify_check_given_host(&ob->hosts_request_ocsp, host) == OK; | |
043b1248 | 2046 | } |
f5d78688 | 2047 | #endif |
059ec3d9 | 2048 | |
65867078 JH |
2049 | rc = tls_init(&client_ctx, host, NULL, |
2050 | ob->tls_certificate, ob->tls_privatekey, | |
f2de3a33 | 2051 | #ifndef DISABLE_OCSP |
44662487 | 2052 | (void *)(long)request_ocsp, |
3f7eeb86 | 2053 | #endif |
817d9f57 | 2054 | addr, &client_static_cbinfo); |
059ec3d9 PH |
2055 | if (rc != OK) return rc; |
2056 | ||
817d9f57 | 2057 | tls_out.certificate_verified = FALSE; |
a2ff477a | 2058 | client_verify_callback_called = FALSE; |
059ec3d9 | 2059 | |
65867078 JH |
2060 | if (!expand_check(ob->tls_require_ciphers, US"tls_require_ciphers", |
2061 | &expciphers)) | |
059ec3d9 PH |
2062 | return FAIL; |
2063 | ||
2064 | /* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they | |
2065 | are separated by underscores. So that I can use either form in my tests, and | |
2066 | also for general convenience, we turn underscores into hyphens here. */ | |
2067 | ||
2068 | if (expciphers != NULL) | |
2069 | { | |
2070 | uschar *s = expciphers; | |
2071 | while (*s != 0) { if (*s == '_') *s = '-'; s++; } | |
2072 | DEBUG(D_tls) debug_printf("required ciphers: %s\n", expciphers); | |
817d9f57 | 2073 | if (!SSL_CTX_set_cipher_list(client_ctx, CS expciphers)) |
7199e1ee | 2074 | return tls_error(US"SSL_CTX_set_cipher_list", host, NULL); |
059ec3d9 PH |
2075 | } |
2076 | ||
043b1248 | 2077 | #ifdef EXPERIMENTAL_DANE |
0e66b3b6 | 2078 | if (tlsa_dnsa) |
a63be306 | 2079 | { |
02af313d JH |
2080 | SSL_CTX_set_verify(client_ctx, |
2081 | SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT, | |
2082 | verify_callback_client_dane); | |
e5cccda9 | 2083 | |
043b1248 | 2084 | if (!DANESSL_library_init()) |
b4161d10 | 2085 | return tls_error(US"library init", host, NULL); |
043b1248 | 2086 | if (DANESSL_CTX_init(client_ctx) <= 0) |
b4161d10 | 2087 | return tls_error(US"context init", host, NULL); |
043b1248 JH |
2088 | } |
2089 | else | |
e51c7be2 | 2090 | |
043b1248 JH |
2091 | #endif |
2092 | ||
01a4a5c5 JH |
2093 | if ((rc = tls_client_basic_ctx_init(client_ctx, host, ob, client_static_cbinfo)) |
2094 | != OK) | |
65867078 | 2095 | return rc; |
059ec3d9 | 2096 | |
65867078 JH |
2097 | if ((client_ssl = SSL_new(client_ctx)) == NULL) |
2098 | return tls_error(US"SSL_new", host, NULL); | |
817d9f57 JH |
2099 | SSL_set_session_id_context(client_ssl, sid_ctx, Ustrlen(sid_ctx)); |
2100 | SSL_set_fd(client_ssl, fd); | |
2101 | SSL_set_connect_state(client_ssl); | |
059ec3d9 | 2102 | |
65867078 | 2103 | if (ob->tls_sni) |
3f0945ff | 2104 | { |
65867078 | 2105 | if (!expand_check(ob->tls_sni, US"tls_sni", &tls_out.sni)) |
3f0945ff | 2106 | return FAIL; |
ec4b68e5 | 2107 | if (tls_out.sni == NULL) |
2c9a0e86 PP |
2108 | { |
2109 | DEBUG(D_tls) debug_printf("Setting TLS SNI forced to fail, not sending\n"); | |
2110 | } | |
ec4b68e5 | 2111 | else if (!Ustrlen(tls_out.sni)) |
817d9f57 | 2112 | tls_out.sni = NULL; |
3f0945ff PP |
2113 | else |
2114 | { | |
35731706 | 2115 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
817d9f57 JH |
2116 | DEBUG(D_tls) debug_printf("Setting TLS SNI \"%s\"\n", tls_out.sni); |
2117 | SSL_set_tlsext_host_name(client_ssl, tls_out.sni); | |
35731706 | 2118 | #else |
66802652 | 2119 | log_write(0, LOG_MAIN, "SNI unusable with this OpenSSL library version; ignoring \"%s\"\n", |
02d9264f | 2120 | tls_out.sni); |
35731706 | 2121 | #endif |
3f0945ff PP |
2122 | } |
2123 | } | |
2124 | ||
594706ea | 2125 | #ifdef EXPERIMENTAL_DANE |
0e66b3b6 JH |
2126 | if (tlsa_dnsa) |
2127 | if ((rc = dane_tlsa_load(client_ssl, host, tlsa_dnsa)) != OK) | |
594706ea JH |
2128 | return rc; |
2129 | #endif | |
2130 | ||
f2de3a33 | 2131 | #ifndef DISABLE_OCSP |
f5d78688 JH |
2132 | /* Request certificate status at connection-time. If the server |
2133 | does OCSP stapling we will get the callback (set in tls_init()) */ | |
b50c8b84 | 2134 | # ifdef EXPERIMENTAL_DANE |
594706ea JH |
2135 | if (request_ocsp) |
2136 | { | |
2137 | const uschar * s; | |
41afb5cb JH |
2138 | if ( ((s = ob->hosts_require_ocsp) && Ustrstr(s, US"tls_out_tlsa_usage")) |
2139 | || ((s = ob->hosts_request_ocsp) && Ustrstr(s, US"tls_out_tlsa_usage")) | |
594706ea JH |
2140 | ) |
2141 | { /* Re-eval now $tls_out_tlsa_usage is populated. If | |
2142 | this means we avoid the OCSP request, we wasted the setup | |
2143 | cost in tls_init(). */ | |
5130845b JH |
2144 | require_ocsp = verify_check_given_host(&ob->hosts_require_ocsp, host) == OK; |
2145 | request_ocsp = require_ocsp | |
2146 | || verify_check_given_host(&ob->hosts_request_ocsp, host) == OK; | |
594706ea JH |
2147 | } |
2148 | } | |
b50c8b84 JH |
2149 | # endif |
2150 | ||
44662487 JH |
2151 | if (request_ocsp) |
2152 | { | |
f5d78688 | 2153 | SSL_set_tlsext_status_type(client_ssl, TLSEXT_STATUSTYPE_ocsp); |
44662487 JH |
2154 | client_static_cbinfo->u_ocsp.client.verify_required = require_ocsp; |
2155 | tls_out.ocsp = OCSP_NOT_RESP; | |
2156 | } | |
f5d78688 JH |
2157 | #endif |
2158 | ||
0cbf2b82 | 2159 | #ifndef DISABLE_EVENT |
774ef2d7 | 2160 | client_static_cbinfo->event_action = tb->event_action; |
a7538db1 | 2161 | #endif |
043b1248 | 2162 | |
059ec3d9 PH |
2163 | /* There doesn't seem to be a built-in timeout on connection. */ |
2164 | ||
2165 | DEBUG(D_tls) debug_printf("Calling SSL_connect\n"); | |
2166 | sigalrm_seen = FALSE; | |
65867078 | 2167 | alarm(ob->command_timeout); |
817d9f57 | 2168 | rc = SSL_connect(client_ssl); |
059ec3d9 PH |
2169 | alarm(0); |
2170 | ||
043b1248 | 2171 | #ifdef EXPERIMENTAL_DANE |
0e66b3b6 | 2172 | if (tlsa_dnsa) |
fde080a4 | 2173 | DANESSL_cleanup(client_ssl); |
043b1248 JH |
2174 | #endif |
2175 | ||
059ec3d9 | 2176 | if (rc <= 0) |
7199e1ee | 2177 | return tls_error(US"SSL_connect", host, sigalrm_seen ? US"timed out" : NULL); |
059ec3d9 PH |
2178 | |
2179 | DEBUG(D_tls) debug_printf("SSL_connect succeeded\n"); | |
2180 | ||
f69979cf | 2181 | peer_cert(client_ssl, &tls_out, peerdn, sizeof(peerdn)); |
059ec3d9 | 2182 | |
817d9f57 JH |
2183 | construct_cipher_name(client_ssl, cipherbuf, sizeof(cipherbuf), &tls_out.bits); |
2184 | tls_out.cipher = cipherbuf; | |
059ec3d9 | 2185 | |
9d1c15ef JH |
2186 | /* Record the certificate we presented */ |
2187 | { | |
2188 | X509 * crt = SSL_get_certificate(client_ssl); | |
2189 | tls_out.ourcert = crt ? X509_dup(crt) : NULL; | |
2190 | } | |
2191 | ||
817d9f57 | 2192 | tls_out.active = fd; |
059ec3d9 PH |
2193 | return OK; |
2194 | } | |
2195 | ||
2196 | ||
2197 | ||
2198 | ||
2199 | ||
2200 | /************************************************* | |
2201 | * TLS version of getc * | |
2202 | *************************************************/ | |
2203 | ||
2204 | /* This gets the next byte from the TLS input buffer. If the buffer is empty, | |
2205 | it refills the buffer via the SSL reading function. | |
2206 | ||
2207 | Arguments: none | |
2208 | Returns: the next character or EOF | |
817d9f57 JH |
2209 | |
2210 | Only used by the server-side TLS. | |
059ec3d9 PH |
2211 | */ |
2212 | ||
2213 | int | |
2214 | tls_getc(void) | |
2215 | { | |
2216 | if (ssl_xfer_buffer_lwm >= ssl_xfer_buffer_hwm) | |
2217 | { | |
2218 | int error; | |
2219 | int inbytes; | |
2220 | ||
817d9f57 | 2221 | DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", server_ssl, |
c80c5570 | 2222 | ssl_xfer_buffer, ssl_xfer_buffer_size); |
059ec3d9 PH |
2223 | |
2224 | if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout); | |
817d9f57 JH |
2225 | inbytes = SSL_read(server_ssl, CS ssl_xfer_buffer, ssl_xfer_buffer_size); |
2226 | error = SSL_get_error(server_ssl, inbytes); | |
059ec3d9 PH |
2227 | alarm(0); |
2228 | ||
2229 | /* SSL_ERROR_ZERO_RETURN appears to mean that the SSL session has been | |
2230 | closed down, not that the socket itself has been closed down. Revert to | |
2231 | non-SSL handling. */ | |
2232 | ||
2233 | if (error == SSL_ERROR_ZERO_RETURN) | |
2234 | { | |
2235 | DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n"); | |
2236 | ||
2237 | receive_getc = smtp_getc; | |
2238 | receive_ungetc = smtp_ungetc; | |
2239 | receive_feof = smtp_feof; | |
2240 | receive_ferror = smtp_ferror; | |
58eb016e | 2241 | receive_smtp_buffered = smtp_buffered; |
059ec3d9 | 2242 | |
817d9f57 JH |
2243 | SSL_free(server_ssl); |
2244 | server_ssl = NULL; | |
2245 | tls_in.active = -1; | |
2246 | tls_in.bits = 0; | |
2247 | tls_in.cipher = NULL; | |
2248 | tls_in.peerdn = NULL; | |
2249 | tls_in.sni = NULL; | |
059ec3d9 PH |
2250 | |
2251 | return smtp_getc(); | |
2252 | } | |
2253 | ||
2254 | /* Handle genuine errors */ | |
2255 | ||
ba084640 PP |
2256 | else if (error == SSL_ERROR_SSL) |
2257 | { | |
2258 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
89dd51cd | 2259 | log_write(0, LOG_MAIN, "TLS error (SSL_read): %s", ssl_errstring); |
ba084640 PP |
2260 | ssl_xfer_error = 1; |
2261 | return EOF; | |
2262 | } | |
2263 | ||
059ec3d9 PH |
2264 | else if (error != SSL_ERROR_NONE) |
2265 | { | |
2266 | DEBUG(D_tls) debug_printf("Got SSL error %d\n", error); | |
2267 | ssl_xfer_error = 1; | |
2268 | return EOF; | |
2269 | } | |
c80c5570 | 2270 | |
80a47a2c TK |
2271 | #ifndef DISABLE_DKIM |
2272 | dkim_exim_verify_feed(ssl_xfer_buffer, inbytes); | |
2273 | #endif | |
059ec3d9 PH |
2274 | ssl_xfer_buffer_hwm = inbytes; |
2275 | ssl_xfer_buffer_lwm = 0; | |
2276 | } | |
2277 | ||
2278 | /* Something in the buffer; return next uschar */ | |
2279 | ||
2280 | return ssl_xfer_buffer[ssl_xfer_buffer_lwm++]; | |
2281 | } | |
2282 | ||
2283 | ||
2284 | ||
2285 | /************************************************* | |
2286 | * Read bytes from TLS channel * | |
2287 | *************************************************/ | |
2288 | ||
2289 | /* | |
2290 | Arguments: | |
2291 | buff buffer of data | |
2292 | len size of buffer | |
2293 | ||
2294 | Returns: the number of bytes read | |
2295 | -1 after a failed read | |
817d9f57 JH |
2296 | |
2297 | Only used by the client-side TLS. | |
059ec3d9 PH |
2298 | */ |
2299 | ||
2300 | int | |
389ca47a | 2301 | tls_read(BOOL is_server, uschar *buff, size_t len) |
059ec3d9 | 2302 | { |
389ca47a | 2303 | SSL *ssl = is_server ? server_ssl : client_ssl; |
059ec3d9 PH |
2304 | int inbytes; |
2305 | int error; | |
2306 | ||
389ca47a | 2307 | DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", ssl, |
c80c5570 | 2308 | buff, (unsigned int)len); |
059ec3d9 | 2309 | |
389ca47a JH |
2310 | inbytes = SSL_read(ssl, CS buff, len); |
2311 | error = SSL_get_error(ssl, inbytes); | |
059ec3d9 PH |
2312 | |
2313 | if (error == SSL_ERROR_ZERO_RETURN) | |
2314 | { | |
2315 | DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n"); | |
2316 | return -1; | |
2317 | } | |
2318 | else if (error != SSL_ERROR_NONE) | |
2319 | { | |
2320 | return -1; | |
2321 | } | |
2322 | ||
2323 | return inbytes; | |
2324 | } | |
2325 | ||
2326 | ||
2327 | ||
2328 | ||
2329 | ||
2330 | /************************************************* | |
2331 | * Write bytes down TLS channel * | |
2332 | *************************************************/ | |
2333 | ||
2334 | /* | |
2335 | Arguments: | |
817d9f57 | 2336 | is_server channel specifier |
059ec3d9 PH |
2337 | buff buffer of data |
2338 | len number of bytes | |
2339 | ||
2340 | Returns: the number of bytes after a successful write, | |
2341 | -1 after a failed write | |
817d9f57 JH |
2342 | |
2343 | Used by both server-side and client-side TLS. | |
059ec3d9 PH |
2344 | */ |
2345 | ||
2346 | int | |
817d9f57 | 2347 | tls_write(BOOL is_server, const uschar *buff, size_t len) |
059ec3d9 PH |
2348 | { |
2349 | int outbytes; | |
2350 | int error; | |
2351 | int left = len; | |
817d9f57 | 2352 | SSL *ssl = is_server ? server_ssl : client_ssl; |
059ec3d9 | 2353 | |
c80c5570 | 2354 | DEBUG(D_tls) debug_printf("tls_do_write(%p, %d)\n", buff, left); |
059ec3d9 PH |
2355 | while (left > 0) |
2356 | { | |
c80c5570 | 2357 | DEBUG(D_tls) debug_printf("SSL_write(SSL, %p, %d)\n", buff, left); |
059ec3d9 PH |
2358 | outbytes = SSL_write(ssl, CS buff, left); |
2359 | error = SSL_get_error(ssl, outbytes); | |
2360 | DEBUG(D_tls) debug_printf("outbytes=%d error=%d\n", outbytes, error); | |
2361 | switch (error) | |
2362 | { | |
2363 | case SSL_ERROR_SSL: | |
2364 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
2365 | log_write(0, LOG_MAIN, "TLS error (SSL_write): %s", ssl_errstring); | |
2366 | return -1; | |
2367 | ||
2368 | case SSL_ERROR_NONE: | |
2369 | left -= outbytes; | |
2370 | buff += outbytes; | |
2371 | break; | |
2372 | ||
2373 | case SSL_ERROR_ZERO_RETURN: | |
2374 | log_write(0, LOG_MAIN, "SSL channel closed on write"); | |
2375 | return -1; | |
2376 | ||
817d9f57 JH |
2377 | case SSL_ERROR_SYSCALL: |
2378 | log_write(0, LOG_MAIN, "SSL_write: (from %s) syscall: %s", | |
2379 | sender_fullhost ? sender_fullhost : US"<unknown>", | |
2380 | strerror(errno)); | |
2381 | ||
059ec3d9 PH |
2382 | default: |
2383 | log_write(0, LOG_MAIN, "SSL_write error %d", error); | |
2384 | return -1; | |
2385 | } | |
2386 | } | |
2387 | return len; | |
2388 | } | |
2389 | ||
2390 | ||
2391 | ||
2392 | /************************************************* | |
2393 | * Close down a TLS session * | |
2394 | *************************************************/ | |
2395 | ||
2396 | /* This is also called from within a delivery subprocess forked from the | |
2397 | daemon, to shut down the TLS library, without actually doing a shutdown (which | |
2398 | would tamper with the SSL session in the parent process). | |
2399 | ||
2400 | Arguments: TRUE if SSL_shutdown is to be called | |
2401 | Returns: nothing | |
817d9f57 JH |
2402 | |
2403 | Used by both server-side and client-side TLS. | |
059ec3d9 PH |
2404 | */ |
2405 | ||
2406 | void | |
817d9f57 | 2407 | tls_close(BOOL is_server, BOOL shutdown) |
059ec3d9 | 2408 | { |
817d9f57 | 2409 | SSL **sslp = is_server ? &server_ssl : &client_ssl; |
389ca47a | 2410 | int *fdp = is_server ? &tls_in.active : &tls_out.active; |
817d9f57 JH |
2411 | |
2412 | if (*fdp < 0) return; /* TLS was not active */ | |
059ec3d9 PH |
2413 | |
2414 | if (shutdown) | |
2415 | { | |
2416 | DEBUG(D_tls) debug_printf("tls_close(): shutting down SSL\n"); | |
817d9f57 | 2417 | SSL_shutdown(*sslp); |
059ec3d9 PH |
2418 | } |
2419 | ||
817d9f57 JH |
2420 | SSL_free(*sslp); |
2421 | *sslp = NULL; | |
059ec3d9 | 2422 | |
817d9f57 | 2423 | *fdp = -1; |
059ec3d9 PH |
2424 | } |
2425 | ||
36f12725 NM |
2426 | |
2427 | ||
2428 | ||
3375e053 PP |
2429 | /************************************************* |
2430 | * Let tls_require_ciphers be checked at startup * | |
2431 | *************************************************/ | |
2432 | ||
2433 | /* The tls_require_ciphers option, if set, must be something which the | |
2434 | library can parse. | |
2435 | ||
2436 | Returns: NULL on success, or error message | |
2437 | */ | |
2438 | ||
2439 | uschar * | |
2440 | tls_validate_require_cipher(void) | |
2441 | { | |
2442 | SSL_CTX *ctx; | |
2443 | uschar *s, *expciphers, *err; | |
2444 | ||
2445 | /* this duplicates from tls_init(), we need a better "init just global | |
2446 | state, for no specific purpose" singleton function of our own */ | |
2447 | ||
2448 | SSL_load_error_strings(); | |
2449 | OpenSSL_add_ssl_algorithms(); | |
2450 | #if (OPENSSL_VERSION_NUMBER >= 0x0090800fL) && !defined(OPENSSL_NO_SHA256) | |
2451 | /* SHA256 is becoming ever more popular. This makes sure it gets added to the | |
2452 | list of available digests. */ | |
2453 | EVP_add_digest(EVP_sha256()); | |
2454 | #endif | |
2455 | ||
2456 | if (!(tls_require_ciphers && *tls_require_ciphers)) | |
2457 | return NULL; | |
2458 | ||
2459 | if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers)) | |
2460 | return US"failed to expand tls_require_ciphers"; | |
2461 | ||
2462 | if (!(expciphers && *expciphers)) | |
2463 | return NULL; | |
2464 | ||
2465 | /* normalisation ripped from above */ | |
2466 | s = expciphers; | |
2467 | while (*s != 0) { if (*s == '_') *s = '-'; s++; } | |
2468 | ||
2469 | err = NULL; | |
2470 | ||
2471 | ctx = SSL_CTX_new(SSLv23_server_method()); | |
2472 | if (!ctx) | |
2473 | { | |
2474 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
2475 | return string_sprintf("SSL_CTX_new() failed: %s", ssl_errstring); | |
2476 | } | |
2477 | ||
2478 | DEBUG(D_tls) | |
2479 | debug_printf("tls_require_ciphers expands to \"%s\"\n", expciphers); | |
2480 | ||
2481 | if (!SSL_CTX_set_cipher_list(ctx, CS expciphers)) | |
2482 | { | |
2483 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
2484 | err = string_sprintf("SSL_CTX_set_cipher_list(%s) failed", expciphers); | |
2485 | } | |
2486 | ||
2487 | SSL_CTX_free(ctx); | |
2488 | ||
2489 | return err; | |
2490 | } | |
2491 | ||
2492 | ||
2493 | ||
2494 | ||
36f12725 NM |
2495 | /************************************************* |
2496 | * Report the library versions. * | |
2497 | *************************************************/ | |
2498 | ||
2499 | /* There have historically been some issues with binary compatibility in | |
2500 | OpenSSL libraries; if Exim (like many other applications) is built against | |
2501 | one version of OpenSSL but the run-time linker picks up another version, | |
2502 | it can result in serious failures, including crashing with a SIGSEGV. So | |
2503 | report the version found by the compiler and the run-time version. | |
2504 | ||
f64a1e23 PP |
2505 | Note: some OS vendors backport security fixes without changing the version |
2506 | number/string, and the version date remains unchanged. The _build_ date | |
2507 | will change, so we can more usefully assist with version diagnosis by also | |
2508 | reporting the build date. | |
2509 | ||
36f12725 NM |
2510 | Arguments: a FILE* to print the results to |
2511 | Returns: nothing | |
2512 | */ | |
2513 | ||
2514 | void | |
2515 | tls_version_report(FILE *f) | |
2516 | { | |
754a0503 | 2517 | fprintf(f, "Library version: OpenSSL: Compile: %s\n" |
f64a1e23 PP |
2518 | " Runtime: %s\n" |
2519 | " : %s\n", | |
754a0503 | 2520 | OPENSSL_VERSION_TEXT, |
f64a1e23 PP |
2521 | SSLeay_version(SSLEAY_VERSION), |
2522 | SSLeay_version(SSLEAY_BUILT_ON)); | |
2523 | /* third line is 38 characters for the %s and the line is 73 chars long; | |
2524 | the OpenSSL output includes a "built on: " prefix already. */ | |
36f12725 NM |
2525 | } |
2526 | ||
9e3331ea TK |
2527 | |
2528 | ||
2529 | ||
2530 | /************************************************* | |
17c76198 | 2531 | * Random number generation * |
9e3331ea TK |
2532 | *************************************************/ |
2533 | ||
2534 | /* Pseudo-random number generation. The result is not expected to be | |
2535 | cryptographically strong but not so weak that someone will shoot themselves | |
2536 | in the foot using it as a nonce in input in some email header scheme or | |
2537 | whatever weirdness they'll twist this into. The result should handle fork() | |
2538 | and avoid repeating sequences. OpenSSL handles that for us. | |
2539 | ||
2540 | Arguments: | |
2541 | max range maximum | |
2542 | Returns a random number in range [0, max-1] | |
2543 | */ | |
2544 | ||
2545 | int | |
17c76198 | 2546 | vaguely_random_number(int max) |
9e3331ea TK |
2547 | { |
2548 | unsigned int r; | |
2549 | int i, needed_len; | |
de6135a0 PP |
2550 | static pid_t pidlast = 0; |
2551 | pid_t pidnow; | |
9e3331ea TK |
2552 | uschar *p; |
2553 | uschar smallbuf[sizeof(r)]; | |
2554 | ||
2555 | if (max <= 1) | |
2556 | return 0; | |
2557 | ||
de6135a0 PP |
2558 | pidnow = getpid(); |
2559 | if (pidnow != pidlast) | |
2560 | { | |
2561 | /* Although OpenSSL documents that "OpenSSL makes sure that the PRNG state | |
2562 | is unique for each thread", this doesn't apparently apply across processes, | |
2563 | so our own warning from vaguely_random_number_fallback() applies here too. | |
2564 | Fix per PostgreSQL. */ | |
2565 | if (pidlast != 0) | |
2566 | RAND_cleanup(); | |
2567 | pidlast = pidnow; | |
2568 | } | |
2569 | ||
9e3331ea TK |
2570 | /* OpenSSL auto-seeds from /dev/random, etc, but this a double-check. */ |
2571 | if (!RAND_status()) | |
2572 | { | |
2573 | randstuff r; | |
2574 | gettimeofday(&r.tv, NULL); | |
2575 | r.p = getpid(); | |
2576 | ||
2577 | RAND_seed((uschar *)(&r), sizeof(r)); | |
2578 | } | |
2579 | /* We're after pseudo-random, not random; if we still don't have enough data | |
2580 | in the internal PRNG then our options are limited. We could sleep and hope | |
2581 | for entropy to come along (prayer technique) but if the system is so depleted | |
2582 | in the first place then something is likely to just keep taking it. Instead, | |
2583 | we'll just take whatever little bit of pseudo-random we can still manage to | |
2584 | get. */ | |
2585 | ||
2586 | needed_len = sizeof(r); | |
2587 | /* Don't take 8 times more entropy than needed if int is 8 octets and we were | |
2588 | asked for a number less than 10. */ | |
2589 | for (r = max, i = 0; r; ++i) | |
2590 | r >>= 1; | |
2591 | i = (i + 7) / 8; | |
2592 | if (i < needed_len) | |
2593 | needed_len = i; | |
2594 | ||
c8dfb21d | 2595 | #ifdef EXIM_HAVE_RAND_PSEUDO |
9e3331ea | 2596 | /* We do not care if crypto-strong */ |
17c76198 | 2597 | i = RAND_pseudo_bytes(smallbuf, needed_len); |
c8dfb21d JH |
2598 | #else |
2599 | i = RAND_bytes(smallbuf, needed_len); | |
2600 | #endif | |
2601 | ||
17c76198 PP |
2602 | if (i < 0) |
2603 | { | |
2604 | DEBUG(D_all) | |
2605 | debug_printf("OpenSSL RAND_pseudo_bytes() not supported by RAND method, using fallback.\n"); | |
2606 | return vaguely_random_number_fallback(max); | |
2607 | } | |
2608 | ||
9e3331ea TK |
2609 | r = 0; |
2610 | for (p = smallbuf; needed_len; --needed_len, ++p) | |
2611 | { | |
2612 | r *= 256; | |
2613 | r += *p; | |
2614 | } | |
2615 | ||
2616 | /* We don't particularly care about weighted results; if someone wants | |
2617 | smooth distribution and cares enough then they should submit a patch then. */ | |
2618 | return r % max; | |
2619 | } | |
2620 | ||
77bb000f PP |
2621 | |
2622 | ||
2623 | ||
2624 | /************************************************* | |
2625 | * OpenSSL option parse * | |
2626 | *************************************************/ | |
2627 | ||
2628 | /* Parse one option for tls_openssl_options_parse below | |
2629 | ||
2630 | Arguments: | |
2631 | name one option name | |
2632 | value place to store a value for it | |
2633 | Returns success or failure in parsing | |
2634 | */ | |
2635 | ||
2636 | struct exim_openssl_option { | |
2637 | uschar *name; | |
2638 | long value; | |
2639 | }; | |
2640 | /* We could use a macro to expand, but we need the ifdef and not all the | |
2641 | options document which version they were introduced in. Policylet: include | |
2642 | all options unless explicitly for DTLS, let the administrator choose which | |
2643 | to apply. | |
2644 | ||
2645 | This list is current as of: | |
e2fbf4a2 PP |
2646 | ==> 1.0.1b <== |
2647 | Plus SSL_OP_SAFARI_ECDHE_ECDSA_BUG from 2013-June patch/discussion on openssl-dev | |
2648 | */ | |
77bb000f PP |
2649 | static struct exim_openssl_option exim_openssl_options[] = { |
2650 | /* KEEP SORTED ALPHABETICALLY! */ | |
2651 | #ifdef SSL_OP_ALL | |
73a46702 | 2652 | { US"all", SSL_OP_ALL }, |
77bb000f PP |
2653 | #endif |
2654 | #ifdef SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION | |
73a46702 | 2655 | { US"allow_unsafe_legacy_renegotiation", SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION }, |
77bb000f PP |
2656 | #endif |
2657 | #ifdef SSL_OP_CIPHER_SERVER_PREFERENCE | |
73a46702 | 2658 | { US"cipher_server_preference", SSL_OP_CIPHER_SERVER_PREFERENCE }, |
77bb000f PP |
2659 | #endif |
2660 | #ifdef SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS | |
73a46702 | 2661 | { US"dont_insert_empty_fragments", SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS }, |
77bb000f PP |
2662 | #endif |
2663 | #ifdef SSL_OP_EPHEMERAL_RSA | |
73a46702 | 2664 | { US"ephemeral_rsa", SSL_OP_EPHEMERAL_RSA }, |
77bb000f PP |
2665 | #endif |
2666 | #ifdef SSL_OP_LEGACY_SERVER_CONNECT | |
73a46702 | 2667 | { US"legacy_server_connect", SSL_OP_LEGACY_SERVER_CONNECT }, |
77bb000f PP |
2668 | #endif |
2669 | #ifdef SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER | |
73a46702 | 2670 | { US"microsoft_big_sslv3_buffer", SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER }, |
77bb000f PP |
2671 | #endif |
2672 | #ifdef SSL_OP_MICROSOFT_SESS_ID_BUG | |
73a46702 | 2673 | { US"microsoft_sess_id_bug", SSL_OP_MICROSOFT_SESS_ID_BUG }, |
77bb000f PP |
2674 | #endif |
2675 | #ifdef SSL_OP_MSIE_SSLV2_RSA_PADDING | |
73a46702 | 2676 | { US"msie_sslv2_rsa_padding", SSL_OP_MSIE_SSLV2_RSA_PADDING }, |
77bb000f PP |
2677 | #endif |
2678 | #ifdef SSL_OP_NETSCAPE_CHALLENGE_BUG | |
73a46702 | 2679 | { US"netscape_challenge_bug", SSL_OP_NETSCAPE_CHALLENGE_BUG }, |
77bb000f PP |
2680 | #endif |
2681 | #ifdef SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG | |
73a46702 | 2682 | { US"netscape_reuse_cipher_change_bug", SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG }, |
77bb000f | 2683 | #endif |
c80c5570 PP |
2684 | #ifdef SSL_OP_NO_COMPRESSION |
2685 | { US"no_compression", SSL_OP_NO_COMPRESSION }, | |
2686 | #endif | |
77bb000f | 2687 | #ifdef SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION |
73a46702 | 2688 | { US"no_session_resumption_on_renegotiation", SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION }, |
77bb000f | 2689 | #endif |
c0c7b2da PP |
2690 | #ifdef SSL_OP_NO_SSLv2 |
2691 | { US"no_sslv2", SSL_OP_NO_SSLv2 }, | |
2692 | #endif | |
2693 | #ifdef SSL_OP_NO_SSLv3 | |
2694 | { US"no_sslv3", SSL_OP_NO_SSLv3 }, | |
2695 | #endif | |
2696 | #ifdef SSL_OP_NO_TICKET | |
2697 | { US"no_ticket", SSL_OP_NO_TICKET }, | |
2698 | #endif | |
2699 | #ifdef SSL_OP_NO_TLSv1 | |
2700 | { US"no_tlsv1", SSL_OP_NO_TLSv1 }, | |
2701 | #endif | |
c80c5570 PP |
2702 | #ifdef SSL_OP_NO_TLSv1_1 |
2703 | #if SSL_OP_NO_TLSv1_1 == 0x00000400L | |
2704 | /* Error in chosen value in 1.0.1a; see first item in CHANGES for 1.0.1b */ | |
2705 | #warning OpenSSL 1.0.1a uses a bad value for SSL_OP_NO_TLSv1_1, ignoring | |
2706 | #else | |
2707 | { US"no_tlsv1_1", SSL_OP_NO_TLSv1_1 }, | |
2708 | #endif | |
2709 | #endif | |
2710 | #ifdef SSL_OP_NO_TLSv1_2 | |
2711 | { US"no_tlsv1_2", SSL_OP_NO_TLSv1_2 }, | |
2712 | #endif | |
e2fbf4a2 PP |
2713 | #ifdef SSL_OP_SAFARI_ECDHE_ECDSA_BUG |
2714 | { US"safari_ecdhe_ecdsa_bug", SSL_OP_SAFARI_ECDHE_ECDSA_BUG }, | |
2715 | #endif | |
77bb000f | 2716 | #ifdef SSL_OP_SINGLE_DH_USE |
73a46702 | 2717 | { US"single_dh_use", SSL_OP_SINGLE_DH_USE }, |
77bb000f PP |
2718 | #endif |
2719 | #ifdef SSL_OP_SINGLE_ECDH_USE | |
73a46702 | 2720 | { US"single_ecdh_use", SSL_OP_SINGLE_ECDH_USE }, |
77bb000f PP |
2721 | #endif |
2722 | #ifdef SSL_OP_SSLEAY_080_CLIENT_DH_BUG | |
73a46702 | 2723 | { US"ssleay_080_client_dh_bug", SSL_OP_SSLEAY_080_CLIENT_DH_BUG }, |
77bb000f PP |
2724 | #endif |
2725 | #ifdef SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG | |
73a46702 | 2726 | { US"sslref2_reuse_cert_type_bug", SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG }, |
77bb000f PP |
2727 | #endif |
2728 | #ifdef SSL_OP_TLS_BLOCK_PADDING_BUG | |
73a46702 | 2729 | { US"tls_block_padding_bug", SSL_OP_TLS_BLOCK_PADDING_BUG }, |
77bb000f PP |
2730 | #endif |
2731 | #ifdef SSL_OP_TLS_D5_BUG | |
73a46702 | 2732 | { US"tls_d5_bug", SSL_OP_TLS_D5_BUG }, |
77bb000f PP |
2733 | #endif |
2734 | #ifdef SSL_OP_TLS_ROLLBACK_BUG | |
73a46702 | 2735 | { US"tls_rollback_bug", SSL_OP_TLS_ROLLBACK_BUG }, |
77bb000f PP |
2736 | #endif |
2737 | }; | |
2738 | static int exim_openssl_options_size = | |
2739 | sizeof(exim_openssl_options)/sizeof(struct exim_openssl_option); | |
2740 | ||
c80c5570 | 2741 | |
77bb000f PP |
2742 | static BOOL |
2743 | tls_openssl_one_option_parse(uschar *name, long *value) | |
2744 | { | |
2745 | int first = 0; | |
2746 | int last = exim_openssl_options_size; | |
2747 | while (last > first) | |
2748 | { | |
2749 | int middle = (first + last)/2; | |
2750 | int c = Ustrcmp(name, exim_openssl_options[middle].name); | |
2751 | if (c == 0) | |
2752 | { | |
2753 | *value = exim_openssl_options[middle].value; | |
2754 | return TRUE; | |
2755 | } | |
2756 | else if (c > 0) | |
2757 | first = middle + 1; | |
2758 | else | |
2759 | last = middle; | |
2760 | } | |
2761 | return FALSE; | |
2762 | } | |
2763 | ||
2764 | ||
2765 | ||
2766 | ||
2767 | /************************************************* | |
2768 | * OpenSSL option parsing logic * | |
2769 | *************************************************/ | |
2770 | ||
2771 | /* OpenSSL has a number of compatibility options which an administrator might | |
2772 | reasonably wish to set. Interpret a list similarly to decode_bits(), so that | |
2773 | we look like log_selector. | |
2774 | ||
2775 | Arguments: | |
2776 | option_spec the administrator-supplied string of options | |
2777 | results ptr to long storage for the options bitmap | |
2778 | Returns success or failure | |
2779 | */ | |
2780 | ||
2781 | BOOL | |
2782 | tls_openssl_options_parse(uschar *option_spec, long *results) | |
2783 | { | |
2784 | long result, item; | |
2785 | uschar *s, *end; | |
2786 | uschar keep_c; | |
2787 | BOOL adding, item_parsed; | |
2788 | ||
0e944a0d | 2789 | result = 0L; |
b1770b6e | 2790 | /* Prior to 4.80 we or'd in SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS; removed |
da3ad30d | 2791 | * from default because it increases BEAST susceptibility. */ |
f0f5a555 PP |
2792 | #ifdef SSL_OP_NO_SSLv2 |
2793 | result |= SSL_OP_NO_SSLv2; | |
2794 | #endif | |
a57b6200 JH |
2795 | #ifdef SSL_OP_SINGLE_DH_USE |
2796 | result |= SSL_OP_SINGLE_DH_USE; | |
2797 | #endif | |
77bb000f PP |
2798 | |
2799 | if (option_spec == NULL) | |
2800 | { | |
2801 | *results = result; | |
2802 | return TRUE; | |
2803 | } | |
2804 | ||
2805 | for (s=option_spec; *s != '\0'; /**/) | |
2806 | { | |
2807 | while (isspace(*s)) ++s; | |
2808 | if (*s == '\0') | |
2809 | break; | |
2810 | if (*s != '+' && *s != '-') | |
2811 | { | |
2812 | DEBUG(D_tls) debug_printf("malformed openssl option setting: " | |
0e944a0d | 2813 | "+ or - expected but found \"%s\"\n", s); |
77bb000f PP |
2814 | return FALSE; |
2815 | } | |
2816 | adding = *s++ == '+'; | |
2817 | for (end = s; (*end != '\0') && !isspace(*end); ++end) /**/ ; | |
2818 | keep_c = *end; | |
2819 | *end = '\0'; | |
2820 | item_parsed = tls_openssl_one_option_parse(s, &item); | |
2821 | if (!item_parsed) | |
2822 | { | |
0e944a0d | 2823 | DEBUG(D_tls) debug_printf("openssl option setting unrecognised: \"%s\"\n", s); |
77bb000f PP |
2824 | return FALSE; |
2825 | } | |
2826 | DEBUG(D_tls) debug_printf("openssl option, %s from %lx: %lx (%s)\n", | |
2827 | adding ? "adding" : "removing", result, item, s); | |
2828 | if (adding) | |
2829 | result |= item; | |
2830 | else | |
2831 | result &= ~item; | |
2832 | *end = keep_c; | |
2833 | s = end; | |
2834 | } | |
2835 | ||
2836 | *results = result; | |
2837 | return TRUE; | |
2838 | } | |
2839 | ||
9d1c15ef JH |
2840 | /* vi: aw ai sw=2 |
2841 | */ | |
059ec3d9 | 2842 | /* End of tls-openssl.c */ |