Commit | Line | Data |
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059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
f9ba5e22 | 5 | /* Copyright (c) University of Cambridge 1995 - 2018 */ |
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 |
c0635b6d | 31 | #ifdef SUPPORT_DANE |
05e796ad | 32 | # include "danessl.h" |
85098ee7 JH |
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) | |
260958d6 | 54 | # define EXIM_HAVE_SHA256 /*MMMM*/ |
c8dfb21d | 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 | |
8420742d | 72 | # define EXIM_HAVE_OPENSSL_DH_BITS |
34e3241d PP |
73 | # endif |
74 | # if OPENSSL_VERSION_NUMBER >= 0x010000000L \ | |
2dfb468b | 75 | && (OPENSSL_VERSION_NUMBER & 0x0000ff000L) >= 0x000002000L |
34e3241d PP |
76 | # define EXIM_HAVE_OPENSSL_CHECKHOST |
77 | # endif | |
11aa88b0 | 78 | #endif |
10ca4f1c | 79 | |
11aa88b0 RA |
80 | #if !defined(LIBRESSL_VERSION_NUMBER) \ |
81 | || LIBRESSL_VERSION_NUMBER >= 0x20010000L | |
10ca4f1c JH |
82 | # if !defined(OPENSSL_NO_ECDH) |
83 | # if OPENSSL_VERSION_NUMBER >= 0x0090800fL | |
260958d6 | 84 | # define EXIM_HAVE_ECDH /*MMMM*/ |
10ca4f1c JH |
85 | # endif |
86 | # if OPENSSL_VERSION_NUMBER >= 0x10002000L | |
10ca4f1c JH |
87 | # define EXIM_HAVE_OPENSSL_EC_NIST2NID |
88 | # endif | |
89 | # endif | |
2dfb468b | 90 | #endif |
3bcbbbe2 | 91 | |
67791ce4 JH |
92 | #if !defined(EXIM_HAVE_OPENSSL_TLSEXT) && !defined(DISABLE_OCSP) |
93 | # warning "OpenSSL library version too old; define DISABLE_OCSP in Makefile" | |
94 | # define DISABLE_OCSP | |
95 | #endif | |
96 | ||
a6510420 JH |
97 | #ifdef EXIM_HAVE_OPENSSL_CHECKHOST |
98 | # include <openssl/x509v3.h> | |
99 | #endif | |
100 | ||
059ec3d9 PH |
101 | /* Structure for collecting random data for seeding. */ |
102 | ||
103 | typedef struct randstuff { | |
9e3331ea TK |
104 | struct timeval tv; |
105 | pid_t p; | |
059ec3d9 PH |
106 | } randstuff; |
107 | ||
108 | /* Local static variables */ | |
109 | ||
a2ff477a JH |
110 | static BOOL client_verify_callback_called = FALSE; |
111 | static BOOL server_verify_callback_called = FALSE; | |
059ec3d9 PH |
112 | static const uschar *sid_ctx = US"exim"; |
113 | ||
d4f09789 PP |
114 | /* We have three different contexts to care about. |
115 | ||
116 | Simple case: client, `client_ctx` | |
117 | As a client, we can be doing a callout or cut-through delivery while receiving | |
118 | a message. So we have a client context, which should have options initialised | |
119 | from the SMTP Transport. | |
120 | ||
121 | Server: | |
122 | There are two cases: with and without ServerNameIndication from the client. | |
123 | Given TLS SNI, we can be using different keys, certs and various other | |
124 | configuration settings, because they're re-expanded with $tls_sni set. This | |
125 | allows vhosting with TLS. This SNI is sent in the handshake. | |
126 | A client might not send SNI, so we need a fallback, and an initial setup too. | |
127 | So as a server, we start out using `server_ctx`. | |
128 | If SNI is sent by the client, then we as server, mid-negotiation, try to clone | |
129 | `server_sni` from `server_ctx` and then initialise settings by re-expanding | |
130 | configuration. | |
131 | */ | |
132 | ||
817d9f57 JH |
133 | static SSL_CTX *client_ctx = NULL; |
134 | static SSL_CTX *server_ctx = NULL; | |
135 | static SSL *client_ssl = NULL; | |
136 | static SSL *server_ssl = NULL; | |
389ca47a | 137 | |
35731706 | 138 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
817d9f57 | 139 | static SSL_CTX *server_sni = NULL; |
35731706 | 140 | #endif |
059ec3d9 PH |
141 | |
142 | static char ssl_errstring[256]; | |
143 | ||
144 | static int ssl_session_timeout = 200; | |
a2ff477a JH |
145 | static BOOL client_verify_optional = FALSE; |
146 | static BOOL server_verify_optional = FALSE; | |
059ec3d9 | 147 | |
f5d78688 | 148 | static BOOL reexpand_tls_files_for_sni = FALSE; |
059ec3d9 PH |
149 | |
150 | ||
7be682ca PP |
151 | typedef struct tls_ext_ctx_cb { |
152 | uschar *certificate; | |
153 | uschar *privatekey; | |
f5d78688 | 154 | BOOL is_server; |
a6510420 | 155 | #ifndef DISABLE_OCSP |
c3033f13 | 156 | STACK_OF(X509) *verify_stack; /* chain for verifying the proof */ |
f5d78688 JH |
157 | union { |
158 | struct { | |
159 | uschar *file; | |
160 | uschar *file_expanded; | |
161 | OCSP_RESPONSE *response; | |
162 | } server; | |
163 | struct { | |
44662487 JH |
164 | X509_STORE *verify_store; /* non-null if status requested */ |
165 | BOOL verify_required; | |
f5d78688 JH |
166 | } client; |
167 | } u_ocsp; | |
3f7eeb86 | 168 | #endif |
7be682ca PP |
169 | uschar *dhparam; |
170 | /* these are cached from first expand */ | |
171 | uschar *server_cipher_list; | |
172 | /* only passed down to tls_error: */ | |
173 | host_item *host; | |
55414b25 | 174 | const uschar * verify_cert_hostnames; |
0cbf2b82 | 175 | #ifndef DISABLE_EVENT |
a7538db1 JH |
176 | uschar * event_action; |
177 | #endif | |
7be682ca PP |
178 | } tls_ext_ctx_cb; |
179 | ||
180 | /* should figure out a cleanup of API to handle state preserved per | |
181 | implementation, for various reasons, which can be void * in the APIs. | |
182 | For now, we hack around it. */ | |
817d9f57 JH |
183 | tls_ext_ctx_cb *client_static_cbinfo = NULL; |
184 | tls_ext_ctx_cb *server_static_cbinfo = NULL; | |
7be682ca PP |
185 | |
186 | static int | |
983207c1 | 187 | setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host, BOOL optional, |
cf0c6164 | 188 | int (*cert_vfy_cb)(int, X509_STORE_CTX *), uschar ** errstr ); |
059ec3d9 | 189 | |
3f7eeb86 | 190 | /* Callbacks */ |
3bcbbbe2 | 191 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
3f7eeb86 | 192 | static int tls_servername_cb(SSL *s, int *ad ARG_UNUSED, void *arg); |
3bcbbbe2 | 193 | #endif |
f2de3a33 | 194 | #ifndef DISABLE_OCSP |
f5d78688 | 195 | static int tls_server_stapling_cb(SSL *s, void *arg); |
3f7eeb86 PP |
196 | #endif |
197 | ||
059ec3d9 PH |
198 | |
199 | /************************************************* | |
200 | * Handle TLS error * | |
201 | *************************************************/ | |
202 | ||
203 | /* Called from lots of places when errors occur before actually starting to do | |
204 | the TLS handshake, that is, while the session is still in clear. Always returns | |
205 | DEFER for a server and FAIL for a client so that most calls can use "return | |
206 | tls_error(...)" to do this processing and then give an appropriate return. A | |
207 | single function is used for both server and client, because it is called from | |
208 | some shared functions. | |
209 | ||
210 | Argument: | |
211 | prefix text to include in the logged error | |
212 | host NULL if setting up a server; | |
213 | the connected host if setting up a client | |
7199e1ee | 214 | msg error message or NULL if we should ask OpenSSL |
cf0c6164 | 215 | errstr pointer to output error message |
059ec3d9 PH |
216 | |
217 | Returns: OK/DEFER/FAIL | |
218 | */ | |
219 | ||
220 | static int | |
cf0c6164 | 221 | tls_error(uschar * prefix, const host_item * host, uschar * msg, uschar ** errstr) |
059ec3d9 | 222 | { |
c562fd30 | 223 | if (!msg) |
7199e1ee TF |
224 | { |
225 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
cf0c6164 | 226 | msg = US ssl_errstring; |
7199e1ee TF |
227 | } |
228 | ||
cf0c6164 JH |
229 | if (errstr) *errstr = string_sprintf("(%s): %s", prefix, msg); |
230 | return host ? FAIL : DEFER; | |
059ec3d9 PH |
231 | } |
232 | ||
233 | ||
234 | ||
235 | /************************************************* | |
236 | * Callback to generate RSA key * | |
237 | *************************************************/ | |
238 | ||
239 | /* | |
240 | Arguments: | |
3ae79556 | 241 | s SSL connection (not used) |
059ec3d9 PH |
242 | export not used |
243 | keylength keylength | |
244 | ||
245 | Returns: pointer to generated key | |
246 | */ | |
247 | ||
248 | static RSA * | |
249 | rsa_callback(SSL *s, int export, int keylength) | |
250 | { | |
251 | RSA *rsa_key; | |
c8dfb21d JH |
252 | #ifdef EXIM_HAVE_RSA_GENKEY_EX |
253 | BIGNUM *bn = BN_new(); | |
254 | #endif | |
255 | ||
059ec3d9 PH |
256 | export = export; /* Shut picky compilers up */ |
257 | DEBUG(D_tls) debug_printf("Generating %d bit RSA key...\n", keylength); | |
c8dfb21d JH |
258 | |
259 | #ifdef EXIM_HAVE_RSA_GENKEY_EX | |
260 | if ( !BN_set_word(bn, (unsigned long)RSA_F4) | |
f2cb6292 | 261 | || !(rsa_key = RSA_new()) |
c8dfb21d JH |
262 | || !RSA_generate_key_ex(rsa_key, keylength, bn, NULL) |
263 | ) | |
264 | #else | |
23bb6982 | 265 | if (!(rsa_key = RSA_generate_key(keylength, RSA_F4, NULL, NULL))) |
c8dfb21d JH |
266 | #endif |
267 | ||
059ec3d9 PH |
268 | { |
269 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
270 | log_write(0, LOG_MAIN|LOG_PANIC, "TLS error (RSA_generate_key): %s", | |
271 | ssl_errstring); | |
272 | return NULL; | |
273 | } | |
274 | return rsa_key; | |
275 | } | |
276 | ||
277 | ||
278 | ||
f5d78688 | 279 | /* Extreme debug |
f2de3a33 | 280 | #ifndef DISABLE_OCSP |
f5d78688 JH |
281 | void |
282 | x509_store_dump_cert_s_names(X509_STORE * store) | |
283 | { | |
284 | STACK_OF(X509_OBJECT) * roots= store->objs; | |
285 | int i; | |
286 | static uschar name[256]; | |
287 | ||
288 | for(i= 0; i<sk_X509_OBJECT_num(roots); i++) | |
289 | { | |
290 | X509_OBJECT * tmp_obj= sk_X509_OBJECT_value(roots, i); | |
291 | if(tmp_obj->type == X509_LU_X509) | |
292 | { | |
293 | X509 * current_cert= tmp_obj->data.x509; | |
294 | X509_NAME_oneline(X509_get_subject_name(current_cert), CS name, sizeof(name)); | |
f69979cf | 295 | name[sizeof(name)-1] = '\0'; |
f5d78688 JH |
296 | debug_printf(" %s\n", name); |
297 | } | |
298 | } | |
299 | } | |
300 | #endif | |
301 | */ | |
302 | ||
059ec3d9 | 303 | |
0cbf2b82 | 304 | #ifndef DISABLE_EVENT |
f69979cf JH |
305 | static int |
306 | verify_event(tls_support * tlsp, X509 * cert, int depth, const uschar * dn, | |
307 | BOOL *calledp, const BOOL *optionalp, const uschar * what) | |
308 | { | |
309 | uschar * ev; | |
310 | uschar * yield; | |
311 | X509 * old_cert; | |
312 | ||
313 | ev = tlsp == &tls_out ? client_static_cbinfo->event_action : event_action; | |
314 | if (ev) | |
315 | { | |
aaba7d03 | 316 | DEBUG(D_tls) debug_printf("verify_event: %s %d\n", what, depth); |
f69979cf JH |
317 | old_cert = tlsp->peercert; |
318 | tlsp->peercert = X509_dup(cert); | |
319 | /* NB we do not bother setting peerdn */ | |
320 | if ((yield = event_raise(ev, US"tls:cert", string_sprintf("%d", depth)))) | |
321 | { | |
322 | log_write(0, LOG_MAIN, "[%s] %s verify denied by event-action: " | |
323 | "depth=%d cert=%s: %s", | |
324 | tlsp == &tls_out ? deliver_host_address : sender_host_address, | |
325 | what, depth, dn, yield); | |
326 | *calledp = TRUE; | |
327 | if (!*optionalp) | |
328 | { | |
329 | if (old_cert) tlsp->peercert = old_cert; /* restore 1st failing cert */ | |
330 | return 1; /* reject (leaving peercert set) */ | |
331 | } | |
332 | DEBUG(D_tls) debug_printf("Event-action verify failure overridden " | |
333 | "(host in tls_try_verify_hosts)\n"); | |
334 | } | |
335 | X509_free(tlsp->peercert); | |
336 | tlsp->peercert = old_cert; | |
337 | } | |
338 | return 0; | |
339 | } | |
340 | #endif | |
341 | ||
059ec3d9 PH |
342 | /************************************************* |
343 | * Callback for verification * | |
344 | *************************************************/ | |
345 | ||
346 | /* The SSL library does certificate verification if set up to do so. This | |
347 | callback has the current yes/no state is in "state". If verification succeeded, | |
f69979cf JH |
348 | we set the certificate-verified flag. If verification failed, what happens |
349 | depends on whether the client is required to present a verifiable certificate | |
350 | or not. | |
059ec3d9 PH |
351 | |
352 | If verification is optional, we change the state to yes, but still log the | |
353 | verification error. For some reason (it really would help to have proper | |
354 | documentation of OpenSSL), this callback function then gets called again, this | |
f69979cf JH |
355 | time with state = 1. We must take care not to set the private verified flag on |
356 | the second time through. | |
059ec3d9 PH |
357 | |
358 | Note: this function is not called if the client fails to present a certificate | |
359 | when asked. We get here only if a certificate has been received. Handling of | |
360 | optional verification for this case is done when requesting SSL to verify, by | |
361 | setting SSL_VERIFY_FAIL_IF_NO_PEER_CERT in the non-optional case. | |
362 | ||
a7538db1 JH |
363 | May be called multiple times for different issues with a certificate, even |
364 | for a given "depth" in the certificate chain. | |
365 | ||
059ec3d9 | 366 | Arguments: |
f2f2c91b JH |
367 | preverify_ok current yes/no state as 1/0 |
368 | x509ctx certificate information. | |
369 | tlsp per-direction (client vs. server) support data | |
370 | calledp has-been-called flag | |
371 | optionalp verification-is-optional flag | |
059ec3d9 | 372 | |
f2f2c91b | 373 | Returns: 0 if verification should fail, otherwise 1 |
059ec3d9 PH |
374 | */ |
375 | ||
376 | static int | |
f2f2c91b | 377 | verify_callback(int preverify_ok, X509_STORE_CTX *x509ctx, |
421aff85 | 378 | tls_support *tlsp, BOOL *calledp, BOOL *optionalp) |
059ec3d9 | 379 | { |
421aff85 | 380 | X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx); |
a7538db1 | 381 | int depth = X509_STORE_CTX_get_error_depth(x509ctx); |
f69979cf | 382 | uschar dn[256]; |
059ec3d9 | 383 | |
f69979cf JH |
384 | X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn)); |
385 | dn[sizeof(dn)-1] = '\0'; | |
059ec3d9 | 386 | |
f2f2c91b | 387 | if (preverify_ok == 0) |
059ec3d9 | 388 | { |
f77197ae JH |
389 | uschar * extra = verify_mode ? string_sprintf(" (during %c-verify for [%s])", |
390 | *verify_mode, sender_host_address) | |
391 | : US""; | |
392 | log_write(0, LOG_MAIN, "[%s] SSL verify error%s: depth=%d error=%s cert=%s", | |
393 | tlsp == &tls_out ? deliver_host_address : sender_host_address, | |
394 | extra, depth, | |
395 | X509_verify_cert_error_string(X509_STORE_CTX_get_error(x509ctx)), dn); | |
a2ff477a | 396 | *calledp = TRUE; |
9d1c15ef JH |
397 | if (!*optionalp) |
398 | { | |
f69979cf JH |
399 | if (!tlsp->peercert) |
400 | tlsp->peercert = X509_dup(cert); /* record failing cert */ | |
401 | return 0; /* reject */ | |
9d1c15ef | 402 | } |
059ec3d9 PH |
403 | DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in " |
404 | "tls_try_verify_hosts)\n"); | |
059ec3d9 PH |
405 | } |
406 | ||
a7538db1 | 407 | else if (depth != 0) |
059ec3d9 | 408 | { |
f69979cf | 409 | DEBUG(D_tls) debug_printf("SSL verify ok: depth=%d SN=%s\n", depth, dn); |
f2de3a33 | 410 | #ifndef DISABLE_OCSP |
f5d78688 JH |
411 | if (tlsp == &tls_out && client_static_cbinfo->u_ocsp.client.verify_store) |
412 | { /* client, wanting stapling */ | |
413 | /* Add the server cert's signing chain as the one | |
414 | for the verification of the OCSP stapled information. */ | |
94431adb | 415 | |
f5d78688 | 416 | if (!X509_STORE_add_cert(client_static_cbinfo->u_ocsp.client.verify_store, |
421aff85 | 417 | cert)) |
f5d78688 | 418 | ERR_clear_error(); |
c3033f13 | 419 | sk_X509_push(client_static_cbinfo->verify_stack, cert); |
f5d78688 | 420 | } |
a7538db1 | 421 | #endif |
0cbf2b82 | 422 | #ifndef DISABLE_EVENT |
f69979cf JH |
423 | if (verify_event(tlsp, cert, depth, dn, calledp, optionalp, US"SSL")) |
424 | return 0; /* reject, with peercert set */ | |
f5d78688 | 425 | #endif |
059ec3d9 PH |
426 | } |
427 | else | |
428 | { | |
55414b25 | 429 | const uschar * verify_cert_hostnames; |
e51c7be2 | 430 | |
e51c7be2 JH |
431 | if ( tlsp == &tls_out |
432 | && ((verify_cert_hostnames = client_static_cbinfo->verify_cert_hostnames))) | |
433 | /* client, wanting hostname check */ | |
e51c7be2 | 434 | { |
f69979cf | 435 | |
740f36d4 | 436 | #ifdef EXIM_HAVE_OPENSSL_CHECKHOST |
f69979cf JH |
437 | # ifndef X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS |
438 | # define X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS 0 | |
439 | # endif | |
440 | # ifndef X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS | |
441 | # define X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS 0 | |
442 | # endif | |
e51c7be2 | 443 | int sep = 0; |
55414b25 | 444 | const uschar * list = verify_cert_hostnames; |
e51c7be2 | 445 | uschar * name; |
d8e7834a JH |
446 | int rc; |
447 | while ((name = string_nextinlist(&list, &sep, NULL, 0))) | |
f40d5be3 | 448 | if ((rc = X509_check_host(cert, CCS name, 0, |
8d692470 | 449 | X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS |
740f36d4 JH |
450 | | X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS, |
451 | NULL))) | |
d8e7834a JH |
452 | { |
453 | if (rc < 0) | |
454 | { | |
93a6fce2 | 455 | log_write(0, LOG_MAIN, "[%s] SSL verify error: internal error", |
f77197ae | 456 | tlsp == &tls_out ? deliver_host_address : sender_host_address); |
d8e7834a JH |
457 | name = NULL; |
458 | } | |
e51c7be2 | 459 | break; |
d8e7834a | 460 | } |
e51c7be2 | 461 | if (!name) |
f69979cf | 462 | #else |
e51c7be2 | 463 | if (!tls_is_name_for_cert(verify_cert_hostnames, cert)) |
f69979cf | 464 | #endif |
e51c7be2 | 465 | { |
f77197ae JH |
466 | uschar * extra = verify_mode |
467 | ? string_sprintf(" (during %c-verify for [%s])", | |
468 | *verify_mode, sender_host_address) | |
469 | : US""; | |
e51c7be2 | 470 | log_write(0, LOG_MAIN, |
f77197ae JH |
471 | "[%s] SSL verify error%s: certificate name mismatch: DN=\"%s\" H=\"%s\"", |
472 | tlsp == &tls_out ? deliver_host_address : sender_host_address, | |
473 | extra, dn, verify_cert_hostnames); | |
a3ef7310 JH |
474 | *calledp = TRUE; |
475 | if (!*optionalp) | |
f69979cf JH |
476 | { |
477 | if (!tlsp->peercert) | |
478 | tlsp->peercert = X509_dup(cert); /* record failing cert */ | |
479 | return 0; /* reject */ | |
480 | } | |
a3ef7310 JH |
481 | DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in " |
482 | "tls_try_verify_hosts)\n"); | |
e51c7be2 | 483 | } |
f69979cf | 484 | } |
e51c7be2 | 485 | |
0cbf2b82 | 486 | #ifndef DISABLE_EVENT |
f69979cf JH |
487 | if (verify_event(tlsp, cert, depth, dn, calledp, optionalp, US"SSL")) |
488 | return 0; /* reject, with peercert set */ | |
e51c7be2 JH |
489 | #endif |
490 | ||
93dcb1c2 | 491 | DEBUG(D_tls) debug_printf("SSL%s verify ok: depth=0 SN=%s\n", |
f69979cf | 492 | *calledp ? "" : " authenticated", dn); |
93dcb1c2 JH |
493 | if (!*calledp) tlsp->certificate_verified = TRUE; |
494 | *calledp = TRUE; | |
059ec3d9 PH |
495 | } |
496 | ||
a7538db1 | 497 | return 1; /* accept, at least for this level */ |
059ec3d9 PH |
498 | } |
499 | ||
a2ff477a | 500 | static int |
f2f2c91b | 501 | verify_callback_client(int preverify_ok, X509_STORE_CTX *x509ctx) |
a2ff477a | 502 | { |
f2f2c91b JH |
503 | return verify_callback(preverify_ok, x509ctx, &tls_out, |
504 | &client_verify_callback_called, &client_verify_optional); | |
a2ff477a JH |
505 | } |
506 | ||
507 | static int | |
f2f2c91b | 508 | verify_callback_server(int preverify_ok, X509_STORE_CTX *x509ctx) |
a2ff477a | 509 | { |
f2f2c91b JH |
510 | return verify_callback(preverify_ok, x509ctx, &tls_in, |
511 | &server_verify_callback_called, &server_verify_optional); | |
a2ff477a JH |
512 | } |
513 | ||
059ec3d9 | 514 | |
c0635b6d | 515 | #ifdef SUPPORT_DANE |
53a7196b | 516 | |
e5cccda9 JH |
517 | /* This gets called *by* the dane library verify callback, which interposes |
518 | itself. | |
519 | */ | |
520 | static int | |
f2f2c91b | 521 | verify_callback_client_dane(int preverify_ok, X509_STORE_CTX * x509ctx) |
e5cccda9 JH |
522 | { |
523 | X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx); | |
f69979cf | 524 | uschar dn[256]; |
83b27293 | 525 | int depth = X509_STORE_CTX_get_error_depth(x509ctx); |
5c75db2e | 526 | #ifndef DISABLE_EVENT |
f69979cf | 527 | BOOL dummy_called, optional = FALSE; |
83b27293 | 528 | #endif |
e5cccda9 | 529 | |
f69979cf JH |
530 | X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn)); |
531 | dn[sizeof(dn)-1] = '\0'; | |
e5cccda9 | 532 | |
f2f2c91b JH |
533 | DEBUG(D_tls) debug_printf("verify_callback_client_dane: %s depth %d %s\n", |
534 | preverify_ok ? "ok":"BAD", depth, dn); | |
e5cccda9 | 535 | |
0cbf2b82 | 536 | #ifndef DISABLE_EVENT |
f69979cf JH |
537 | if (verify_event(&tls_out, cert, depth, dn, |
538 | &dummy_called, &optional, US"DANE")) | |
539 | return 0; /* reject, with peercert set */ | |
83b27293 JH |
540 | #endif |
541 | ||
f2f2c91b | 542 | if (preverify_ok == 1) |
6fbf3599 JH |
543 | { |
544 | tls_out.dane_verified = tls_out.certificate_verified = TRUE; | |
545 | #ifndef DISABLE_OCSP | |
546 | if (client_static_cbinfo->u_ocsp.client.verify_store) | |
547 | { /* client, wanting stapling */ | |
548 | /* Add the server cert's signing chain as the one | |
549 | for the verification of the OCSP stapled information. */ | |
550 | ||
551 | if (!X509_STORE_add_cert(client_static_cbinfo->u_ocsp.client.verify_store, | |
552 | cert)) | |
553 | ERR_clear_error(); | |
554 | sk_X509_push(client_static_cbinfo->verify_stack, cert); | |
555 | } | |
556 | #endif | |
557 | } | |
f2f2c91b JH |
558 | else |
559 | { | |
560 | int err = X509_STORE_CTX_get_error(x509ctx); | |
561 | DEBUG(D_tls) | |
562 | debug_printf(" - err %d '%s'\n", err, X509_verify_cert_error_string(err)); | |
3c51463e | 563 | if (err == X509_V_ERR_APPLICATION_VERIFICATION) |
f2f2c91b JH |
564 | preverify_ok = 1; |
565 | } | |
566 | return preverify_ok; | |
e5cccda9 | 567 | } |
53a7196b | 568 | |
c0635b6d | 569 | #endif /*SUPPORT_DANE*/ |
e5cccda9 | 570 | |
059ec3d9 PH |
571 | |
572 | /************************************************* | |
573 | * Information callback * | |
574 | *************************************************/ | |
575 | ||
576 | /* The SSL library functions call this from time to time to indicate what they | |
7be682ca PP |
577 | are doing. We copy the string to the debugging output when TLS debugging has |
578 | been requested. | |
059ec3d9 PH |
579 | |
580 | Arguments: | |
581 | s the SSL connection | |
582 | where | |
583 | ret | |
584 | ||
585 | Returns: nothing | |
586 | */ | |
587 | ||
588 | static void | |
589 | info_callback(SSL *s, int where, int ret) | |
590 | { | |
591 | where = where; | |
592 | ret = ret; | |
593 | DEBUG(D_tls) debug_printf("SSL info: %s\n", SSL_state_string_long(s)); | |
594 | } | |
595 | ||
596 | ||
597 | ||
598 | /************************************************* | |
599 | * Initialize for DH * | |
600 | *************************************************/ | |
601 | ||
602 | /* If dhparam is set, expand it, and load up the parameters for DH encryption. | |
603 | ||
604 | Arguments: | |
038597d2 | 605 | sctx The current SSL CTX (inbound or outbound) |
a799883d | 606 | dhparam DH parameter file or fixed parameter identity string |
7199e1ee | 607 | host connected host, if client; NULL if server |
cf0c6164 | 608 | errstr error string pointer |
059ec3d9 PH |
609 | |
610 | Returns: TRUE if OK (nothing to set up, or setup worked) | |
611 | */ | |
612 | ||
613 | static BOOL | |
cf0c6164 | 614 | init_dh(SSL_CTX *sctx, uschar *dhparam, const host_item *host, uschar ** errstr) |
059ec3d9 | 615 | { |
059ec3d9 PH |
616 | BIO *bio; |
617 | DH *dh; | |
618 | uschar *dhexpanded; | |
a799883d | 619 | const char *pem; |
6600985a | 620 | int dh_bitsize; |
059ec3d9 | 621 | |
cf0c6164 | 622 | if (!expand_check(dhparam, US"tls_dhparam", &dhexpanded, errstr)) |
059ec3d9 PH |
623 | return FALSE; |
624 | ||
0df4ab80 | 625 | if (!dhexpanded || !*dhexpanded) |
a799883d | 626 | bio = BIO_new_mem_buf(CS std_dh_prime_default(), -1); |
a799883d | 627 | else if (dhexpanded[0] == '/') |
059ec3d9 | 628 | { |
0df4ab80 | 629 | if (!(bio = BIO_new_file(CS dhexpanded, "r"))) |
059ec3d9 | 630 | { |
7199e1ee | 631 | tls_error(string_sprintf("could not read dhparams file %s", dhexpanded), |
cf0c6164 | 632 | host, US strerror(errno), errstr); |
a799883d | 633 | return FALSE; |
059ec3d9 | 634 | } |
a799883d PP |
635 | } |
636 | else | |
637 | { | |
638 | if (Ustrcmp(dhexpanded, "none") == 0) | |
059ec3d9 | 639 | { |
a799883d PP |
640 | DEBUG(D_tls) debug_printf("Requested no DH parameters.\n"); |
641 | return TRUE; | |
059ec3d9 | 642 | } |
a799883d | 643 | |
0df4ab80 | 644 | if (!(pem = std_dh_prime_named(dhexpanded))) |
a799883d PP |
645 | { |
646 | tls_error(string_sprintf("Unknown standard DH prime \"%s\"", dhexpanded), | |
cf0c6164 | 647 | host, US strerror(errno), errstr); |
a799883d PP |
648 | return FALSE; |
649 | } | |
650 | bio = BIO_new_mem_buf(CS pem, -1); | |
651 | } | |
652 | ||
0df4ab80 | 653 | if (!(dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL))) |
a799883d | 654 | { |
059ec3d9 | 655 | BIO_free(bio); |
a799883d | 656 | tls_error(string_sprintf("Could not read tls_dhparams \"%s\"", dhexpanded), |
cf0c6164 | 657 | host, NULL, errstr); |
a799883d PP |
658 | return FALSE; |
659 | } | |
660 | ||
6600985a PP |
661 | /* note: our default limit of 2236 is not a multiple of 8; the limit comes from |
662 | * an NSS limit, and the GnuTLS APIs handle bit-sizes fine, so we went with | |
663 | * 2236. But older OpenSSL can only report in bytes (octets), not bits. | |
664 | * If someone wants to dance at the edge, then they can raise the limit or use | |
665 | * current libraries. */ | |
666 | #ifdef EXIM_HAVE_OPENSSL_DH_BITS | |
667 | /* Added in commit 26c79d5641d; `git describe --contains` says OpenSSL_1_1_0-pre1~1022 | |
668 | * This predates OpenSSL_1_1_0 (before a, b, ...) so is in all 1.1.0 */ | |
669 | dh_bitsize = DH_bits(dh); | |
670 | #else | |
671 | dh_bitsize = 8 * DH_size(dh); | |
672 | #endif | |
673 | ||
a799883d PP |
674 | /* Even if it is larger, we silently return success rather than cause things |
675 | * to fail out, so that a too-large DH will not knock out all TLS; it's a | |
676 | * debatable choice. */ | |
6600985a | 677 | if (dh_bitsize > tls_dh_max_bits) |
a799883d PP |
678 | { |
679 | DEBUG(D_tls) | |
170f4904 | 680 | debug_printf("dhparams file %d bits, is > tls_dh_max_bits limit of %d\n", |
6600985a | 681 | dh_bitsize, tls_dh_max_bits); |
a799883d PP |
682 | } |
683 | else | |
684 | { | |
685 | SSL_CTX_set_tmp_dh(sctx, dh); | |
686 | DEBUG(D_tls) | |
687 | debug_printf("Diffie-Hellman initialized from %s with %d-bit prime\n", | |
6600985a | 688 | dhexpanded ? dhexpanded : US"default", dh_bitsize); |
059ec3d9 PH |
689 | } |
690 | ||
a799883d PP |
691 | DH_free(dh); |
692 | BIO_free(bio); | |
693 | ||
694 | return TRUE; | |
059ec3d9 PH |
695 | } |
696 | ||
697 | ||
698 | ||
699 | ||
038597d2 PP |
700 | /************************************************* |
701 | * Initialize for ECDH * | |
702 | *************************************************/ | |
703 | ||
704 | /* Load parameters for ECDH encryption. | |
705 | ||
706 | For now, we stick to NIST P-256 because: it's simple and easy to configure; | |
707 | it avoids any patent issues that might bite redistributors; despite events in | |
708 | the news and concerns over curve choices, we're not cryptographers, we're not | |
709 | pretending to be, and this is "good enough" to be better than no support, | |
710 | protecting against most adversaries. Given another year or two, there might | |
711 | be sufficient clarity about a "right" way forward to let us make an informed | |
712 | decision, instead of a knee-jerk reaction. | |
713 | ||
714 | Longer-term, we should look at supporting both various named curves and | |
715 | external files generated with "openssl ecparam", much as we do for init_dh(). | |
716 | We should also support "none" as a value, to explicitly avoid initialisation. | |
717 | ||
718 | Patches welcome. | |
719 | ||
720 | Arguments: | |
721 | sctx The current SSL CTX (inbound or outbound) | |
722 | host connected host, if client; NULL if server | |
cf0c6164 | 723 | errstr error string pointer |
038597d2 PP |
724 | |
725 | Returns: TRUE if OK (nothing to set up, or setup worked) | |
726 | */ | |
727 | ||
728 | static BOOL | |
cf0c6164 | 729 | init_ecdh(SSL_CTX * sctx, host_item * host, uschar ** errstr) |
038597d2 | 730 | { |
63f0dbe0 JH |
731 | #ifdef OPENSSL_NO_ECDH |
732 | return TRUE; | |
733 | #else | |
734 | ||
10ca4f1c JH |
735 | EC_KEY * ecdh; |
736 | uschar * exp_curve; | |
737 | int nid; | |
738 | BOOL rv; | |
739 | ||
038597d2 PP |
740 | if (host) /* No ECDH setup for clients, only for servers */ |
741 | return TRUE; | |
742 | ||
10ca4f1c | 743 | # ifndef EXIM_HAVE_ECDH |
038597d2 PP |
744 | DEBUG(D_tls) |
745 | debug_printf("No OpenSSL API to define ECDH parameters, skipping\n"); | |
746 | return TRUE; | |
038597d2 | 747 | # else |
10ca4f1c | 748 | |
cf0c6164 | 749 | if (!expand_check(tls_eccurve, US"tls_eccurve", &exp_curve, errstr)) |
10ca4f1c JH |
750 | return FALSE; |
751 | if (!exp_curve || !*exp_curve) | |
752 | return TRUE; | |
753 | ||
8e53a4fc | 754 | /* "auto" needs to be handled carefully. |
4c04137d | 755 | * OpenSSL < 1.0.2: we do not select anything, but fallback to prime256v1 |
8e53a4fc | 756 | * OpenSSL < 1.1.0: we have to call SSL_CTX_set_ecdh_auto |
4c04137d | 757 | * (openssl/ssl.h defines SSL_CTRL_SET_ECDH_AUTO) |
8e53a4fc HSHR |
758 | * OpenSSL >= 1.1.0: we do not set anything, the libray does autoselection |
759 | * https://github.com/openssl/openssl/commit/fe6ef2472db933f01b59cad82aa925736935984b | |
760 | */ | |
10ca4f1c | 761 | if (Ustrcmp(exp_curve, "auto") == 0) |
038597d2 | 762 | { |
8e53a4fc | 763 | #if OPENSSL_VERSION_NUMBER < 0x10002000L |
10ca4f1c | 764 | DEBUG(D_tls) debug_printf( |
8e53a4fc | 765 | "ECDH OpenSSL < 1.0.2: temp key parameter settings: overriding \"auto\" with \"prime256v1\"\n"); |
78a3bbd5 | 766 | exp_curve = US"prime256v1"; |
8e53a4fc HSHR |
767 | #else |
768 | # if defined SSL_CTRL_SET_ECDH_AUTO | |
769 | DEBUG(D_tls) debug_printf( | |
770 | "ECDH OpenSSL 1.0.2+ temp key parameter settings: autoselection\n"); | |
10ca4f1c JH |
771 | SSL_CTX_set_ecdh_auto(sctx, 1); |
772 | return TRUE; | |
8e53a4fc HSHR |
773 | # else |
774 | DEBUG(D_tls) debug_printf( | |
775 | "ECDH OpenSSL 1.1.0+ temp key parameter settings: default selection\n"); | |
776 | return TRUE; | |
777 | # endif | |
778 | #endif | |
10ca4f1c | 779 | } |
038597d2 | 780 | |
10ca4f1c JH |
781 | DEBUG(D_tls) debug_printf("ECDH: curve '%s'\n", exp_curve); |
782 | if ( (nid = OBJ_sn2nid (CCS exp_curve)) == NID_undef | |
783 | # ifdef EXIM_HAVE_OPENSSL_EC_NIST2NID | |
784 | && (nid = EC_curve_nist2nid(CCS exp_curve)) == NID_undef | |
785 | # endif | |
786 | ) | |
787 | { | |
cf0c6164 JH |
788 | tls_error(string_sprintf("Unknown curve name tls_eccurve '%s'", exp_curve), |
789 | host, NULL, errstr); | |
10ca4f1c JH |
790 | return FALSE; |
791 | } | |
038597d2 | 792 | |
10ca4f1c JH |
793 | if (!(ecdh = EC_KEY_new_by_curve_name(nid))) |
794 | { | |
cf0c6164 | 795 | tls_error(US"Unable to create ec curve", host, NULL, errstr); |
10ca4f1c | 796 | return FALSE; |
038597d2 | 797 | } |
10ca4f1c JH |
798 | |
799 | /* The "tmp" in the name here refers to setting a temporary key | |
800 | not to the stability of the interface. */ | |
801 | ||
802 | if ((rv = SSL_CTX_set_tmp_ecdh(sctx, ecdh) == 0)) | |
cf0c6164 | 803 | tls_error(string_sprintf("Error enabling '%s' curve", exp_curve), host, NULL, errstr); |
10ca4f1c JH |
804 | else |
805 | DEBUG(D_tls) debug_printf("ECDH: enabled '%s' curve\n", exp_curve); | |
806 | ||
807 | EC_KEY_free(ecdh); | |
808 | return !rv; | |
809 | ||
810 | # endif /*EXIM_HAVE_ECDH*/ | |
811 | #endif /*OPENSSL_NO_ECDH*/ | |
038597d2 PP |
812 | } |
813 | ||
814 | ||
815 | ||
816 | ||
f2de3a33 | 817 | #ifndef DISABLE_OCSP |
3f7eeb86 PP |
818 | /************************************************* |
819 | * Load OCSP information into state * | |
820 | *************************************************/ | |
f5d78688 | 821 | /* Called to load the server OCSP response from the given file into memory, once |
3f7eeb86 PP |
822 | caller has determined this is needed. Checks validity. Debugs a message |
823 | if invalid. | |
824 | ||
825 | ASSUMES: single response, for single cert. | |
826 | ||
827 | Arguments: | |
828 | sctx the SSL_CTX* to update | |
829 | cbinfo various parts of session state | |
830 | expanded the filename putatively holding an OCSP response | |
831 | ||
832 | */ | |
833 | ||
834 | static void | |
f5d78688 | 835 | ocsp_load_response(SSL_CTX *sctx, tls_ext_ctx_cb *cbinfo, const uschar *expanded) |
3f7eeb86 | 836 | { |
ee5b1e28 JH |
837 | BIO * bio; |
838 | OCSP_RESPONSE * resp; | |
839 | OCSP_BASICRESP * basic_response; | |
840 | OCSP_SINGLERESP * single_response; | |
841 | ASN1_GENERALIZEDTIME * rev, * thisupd, * nextupd; | |
ee5b1e28 | 842 | STACK_OF(X509) * sk; |
3f7eeb86 PP |
843 | unsigned long verify_flags; |
844 | int status, reason, i; | |
845 | ||
f5d78688 JH |
846 | cbinfo->u_ocsp.server.file_expanded = string_copy(expanded); |
847 | if (cbinfo->u_ocsp.server.response) | |
3f7eeb86 | 848 | { |
f5d78688 JH |
849 | OCSP_RESPONSE_free(cbinfo->u_ocsp.server.response); |
850 | cbinfo->u_ocsp.server.response = NULL; | |
3f7eeb86 PP |
851 | } |
852 | ||
ee5b1e28 | 853 | if (!(bio = BIO_new_file(CS cbinfo->u_ocsp.server.file_expanded, "rb"))) |
3f7eeb86 PP |
854 | { |
855 | DEBUG(D_tls) debug_printf("Failed to open OCSP response file \"%s\"\n", | |
f5d78688 | 856 | cbinfo->u_ocsp.server.file_expanded); |
3f7eeb86 PP |
857 | return; |
858 | } | |
859 | ||
860 | resp = d2i_OCSP_RESPONSE_bio(bio, NULL); | |
861 | BIO_free(bio); | |
862 | if (!resp) | |
863 | { | |
864 | DEBUG(D_tls) debug_printf("Error reading OCSP response.\n"); | |
865 | return; | |
866 | } | |
867 | ||
ee5b1e28 | 868 | if ((status = OCSP_response_status(resp)) != OCSP_RESPONSE_STATUS_SUCCESSFUL) |
3f7eeb86 PP |
869 | { |
870 | DEBUG(D_tls) debug_printf("OCSP response not valid: %s (%d)\n", | |
871 | OCSP_response_status_str(status), status); | |
f5d78688 | 872 | goto bad; |
3f7eeb86 PP |
873 | } |
874 | ||
ee5b1e28 | 875 | if (!(basic_response = OCSP_response_get1_basic(resp))) |
3f7eeb86 PP |
876 | { |
877 | DEBUG(D_tls) | |
878 | debug_printf("OCSP response parse error: unable to extract basic response.\n"); | |
f5d78688 | 879 | goto bad; |
3f7eeb86 PP |
880 | } |
881 | ||
c3033f13 | 882 | sk = cbinfo->verify_stack; |
3f7eeb86 PP |
883 | verify_flags = OCSP_NOVERIFY; /* check sigs, but not purpose */ |
884 | ||
885 | /* May need to expose ability to adjust those flags? | |
886 | OCSP_NOSIGS OCSP_NOVERIFY OCSP_NOCHAIN OCSP_NOCHECKS OCSP_NOEXPLICIT | |
887 | OCSP_TRUSTOTHER OCSP_NOINTERN */ | |
888 | ||
4c04137d | 889 | /* This does a full verify on the OCSP proof before we load it for serving |
ee5b1e28 JH |
890 | up; possibly overkill - just date-checks might be nice enough. |
891 | ||
892 | OCSP_basic_verify takes a "store" arg, but does not | |
893 | use it for the chain verification, which is all we do | |
894 | when OCSP_NOVERIFY is set. The content from the wire | |
895 | "basic_response" and a cert-stack "sk" are all that is used. | |
896 | ||
c3033f13 JH |
897 | We have a stack, loaded in setup_certs() if tls_verify_certificates |
898 | was a file (not a directory, or "system"). It is unfortunate we | |
899 | cannot used the connection context store, as that would neatly | |
900 | handle the "system" case too, but there seems to be no library | |
901 | function for getting a stack from a store. | |
e3555426 | 902 | [ In OpenSSL 1.1 - ? X509_STORE_CTX_get0_chain(ctx) ? ] |
c3033f13 JH |
903 | We do not free the stack since it could be needed a second time for |
904 | SNI handling. | |
905 | ||
4c04137d | 906 | Separately we might try to replace using OCSP_basic_verify() - which seems to not |
5ec37a55 | 907 | be a public interface into the OpenSSL library (there's no manual entry) - |
ee5b1e28 | 908 | But what with? We also use OCSP_basic_verify in the client stapling callback. |
4c04137d | 909 | And there we NEED it; we must verify that status... unless the |
ee5b1e28 JH |
910 | library does it for us anyway? */ |
911 | ||
912 | if ((i = OCSP_basic_verify(basic_response, sk, NULL, verify_flags)) < 0) | |
3f7eeb86 | 913 | { |
ee5b1e28 JH |
914 | DEBUG(D_tls) |
915 | { | |
3f7eeb86 PP |
916 | ERR_error_string(ERR_get_error(), ssl_errstring); |
917 | debug_printf("OCSP response verify failure: %s\n", US ssl_errstring); | |
f5d78688 JH |
918 | } |
919 | goto bad; | |
3f7eeb86 PP |
920 | } |
921 | ||
922 | /* Here's the simplifying assumption: there's only one response, for the | |
923 | one certificate we use, and nothing for anything else in a chain. If this | |
924 | proves false, we need to extract a cert id from our issued cert | |
925 | (tls_certificate) and use that for OCSP_resp_find_status() (which finds the | |
926 | right cert in the stack and then calls OCSP_single_get0_status()). | |
927 | ||
928 | I'm hoping to avoid reworking a bunch more of how we handle state here. */ | |
ee5b1e28 JH |
929 | |
930 | if (!(single_response = OCSP_resp_get0(basic_response, 0))) | |
3f7eeb86 PP |
931 | { |
932 | DEBUG(D_tls) | |
933 | debug_printf("Unable to get first response from OCSP basic response.\n"); | |
f5d78688 | 934 | goto bad; |
3f7eeb86 PP |
935 | } |
936 | ||
937 | status = OCSP_single_get0_status(single_response, &reason, &rev, &thisupd, &nextupd); | |
f5d78688 | 938 | if (status != V_OCSP_CERTSTATUS_GOOD) |
3f7eeb86 | 939 | { |
f5d78688 JH |
940 | DEBUG(D_tls) debug_printf("OCSP response bad cert status: %s (%d) %s (%d)\n", |
941 | OCSP_cert_status_str(status), status, | |
942 | OCSP_crl_reason_str(reason), reason); | |
943 | goto bad; | |
3f7eeb86 PP |
944 | } |
945 | ||
946 | if (!OCSP_check_validity(thisupd, nextupd, EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE)) | |
947 | { | |
948 | DEBUG(D_tls) debug_printf("OCSP status invalid times.\n"); | |
f5d78688 | 949 | goto bad; |
3f7eeb86 PP |
950 | } |
951 | ||
f5d78688 | 952 | supply_response: |
47195144 | 953 | cbinfo->u_ocsp.server.response = resp; /*XXX stack?*/ |
f5d78688 JH |
954 | return; |
955 | ||
956 | bad: | |
018058b2 JH |
957 | if (running_in_test_harness) |
958 | { | |
959 | extern char ** environ; | |
960 | uschar ** p; | |
47195144 | 961 | if (environ) for (p = USS environ; *p; p++) |
018058b2 JH |
962 | if (Ustrncmp(*p, "EXIM_TESTHARNESS_DISABLE_OCSPVALIDITYCHECK", 42) == 0) |
963 | { | |
964 | DEBUG(D_tls) debug_printf("Supplying known bad OCSP response\n"); | |
965 | goto supply_response; | |
966 | } | |
967 | } | |
f5d78688 | 968 | return; |
3f7eeb86 | 969 | } |
f2de3a33 | 970 | #endif /*!DISABLE_OCSP*/ |
3f7eeb86 PP |
971 | |
972 | ||
973 | ||
974 | ||
23bb6982 JH |
975 | /* Create and install a selfsigned certificate, for use in server mode */ |
976 | ||
977 | static int | |
cf0c6164 | 978 | tls_install_selfsign(SSL_CTX * sctx, uschar ** errstr) |
23bb6982 JH |
979 | { |
980 | X509 * x509 = NULL; | |
981 | EVP_PKEY * pkey; | |
982 | RSA * rsa; | |
983 | X509_NAME * name; | |
984 | uschar * where; | |
985 | ||
986 | where = US"allocating pkey"; | |
987 | if (!(pkey = EVP_PKEY_new())) | |
988 | goto err; | |
989 | ||
990 | where = US"allocating cert"; | |
991 | if (!(x509 = X509_new())) | |
992 | goto err; | |
993 | ||
994 | where = US"generating pkey"; | |
3ae79556 | 995 | if (!(rsa = rsa_callback(NULL, 0, 1024))) |
23bb6982 JH |
996 | goto err; |
997 | ||
4c04137d | 998 | where = US"assigning pkey"; |
23bb6982 JH |
999 | if (!EVP_PKEY_assign_RSA(pkey, rsa)) |
1000 | goto err; | |
1001 | ||
1002 | X509_set_version(x509, 2); /* N+1 - version 3 */ | |
1613fd68 | 1003 | ASN1_INTEGER_set(X509_get_serialNumber(x509), 1); |
23bb6982 JH |
1004 | X509_gmtime_adj(X509_get_notBefore(x509), 0); |
1005 | X509_gmtime_adj(X509_get_notAfter(x509), (long)60 * 60); /* 1 hour */ | |
1006 | X509_set_pubkey(x509, pkey); | |
1007 | ||
1008 | name = X509_get_subject_name(x509); | |
1009 | X509_NAME_add_entry_by_txt(name, "C", | |
4dc2379a | 1010 | MBSTRING_ASC, CUS "UK", -1, -1, 0); |
23bb6982 | 1011 | X509_NAME_add_entry_by_txt(name, "O", |
4dc2379a | 1012 | MBSTRING_ASC, CUS "Exim Developers", -1, -1, 0); |
23bb6982 | 1013 | X509_NAME_add_entry_by_txt(name, "CN", |
4dc2379a | 1014 | MBSTRING_ASC, CUS smtp_active_hostname, -1, -1, 0); |
23bb6982 JH |
1015 | X509_set_issuer_name(x509, name); |
1016 | ||
1017 | where = US"signing cert"; | |
1018 | if (!X509_sign(x509, pkey, EVP_md5())) | |
1019 | goto err; | |
1020 | ||
1021 | where = US"installing selfsign cert"; | |
1022 | if (!SSL_CTX_use_certificate(sctx, x509)) | |
1023 | goto err; | |
1024 | ||
1025 | where = US"installing selfsign key"; | |
1026 | if (!SSL_CTX_use_PrivateKey(sctx, pkey)) | |
1027 | goto err; | |
1028 | ||
1029 | return OK; | |
1030 | ||
1031 | err: | |
cf0c6164 | 1032 | (void) tls_error(where, NULL, NULL, errstr); |
23bb6982 JH |
1033 | if (x509) X509_free(x509); |
1034 | if (pkey) EVP_PKEY_free(pkey); | |
1035 | return DEFER; | |
1036 | } | |
1037 | ||
1038 | ||
1039 | ||
1040 | ||
ba86e143 JH |
1041 | static int |
1042 | tls_add_certfile(SSL_CTX * sctx, tls_ext_ctx_cb * cbinfo, uschar * file, | |
1043 | uschar ** errstr) | |
1044 | { | |
1045 | DEBUG(D_tls) debug_printf("tls_certificate file %s\n", file); | |
1046 | if (!SSL_CTX_use_certificate_chain_file(sctx, CS file)) | |
1047 | return tls_error(string_sprintf( | |
1048 | "SSL_CTX_use_certificate_chain_file file=%s", file), | |
1049 | cbinfo->host, NULL, errstr); | |
1050 | return 0; | |
1051 | } | |
1052 | ||
1053 | static int | |
1054 | tls_add_pkeyfile(SSL_CTX * sctx, tls_ext_ctx_cb * cbinfo, uschar * file, | |
1055 | uschar ** errstr) | |
1056 | { | |
1057 | DEBUG(D_tls) debug_printf("tls_privatekey file %s\n", file); | |
1058 | if (!SSL_CTX_use_PrivateKey_file(sctx, CS file, SSL_FILETYPE_PEM)) | |
1059 | return tls_error(string_sprintf( | |
1060 | "SSL_CTX_use_PrivateKey_file file=%s", file), cbinfo->host, NULL, errstr); | |
1061 | return 0; | |
1062 | } | |
1063 | ||
1064 | ||
7be682ca PP |
1065 | /************************************************* |
1066 | * Expand key and cert file specs * | |
1067 | *************************************************/ | |
1068 | ||
f5d78688 | 1069 | /* Called once during tls_init and possibly again during TLS setup, for a |
7be682ca PP |
1070 | new context, if Server Name Indication was used and tls_sni was seen in |
1071 | the certificate string. | |
1072 | ||
1073 | Arguments: | |
1074 | sctx the SSL_CTX* to update | |
1075 | cbinfo various parts of session state | |
cf0c6164 | 1076 | errstr error string pointer |
7be682ca PP |
1077 | |
1078 | Returns: OK/DEFER/FAIL | |
1079 | */ | |
1080 | ||
1081 | static int | |
cf0c6164 JH |
1082 | tls_expand_session_files(SSL_CTX *sctx, tls_ext_ctx_cb *cbinfo, |
1083 | uschar ** errstr) | |
7be682ca PP |
1084 | { |
1085 | uschar *expanded; | |
1086 | ||
23bb6982 | 1087 | if (!cbinfo->certificate) |
7be682ca | 1088 | { |
ba86e143 | 1089 | if (!cbinfo->is_server) /* client */ |
23bb6982 JH |
1090 | return OK; |
1091 | /* server */ | |
cf0c6164 | 1092 | if (tls_install_selfsign(sctx, errstr) != OK) |
23bb6982 | 1093 | return DEFER; |
7be682ca | 1094 | } |
23bb6982 JH |
1095 | else |
1096 | { | |
ba86e143 JH |
1097 | int err; |
1098 | ||
23bb6982 JH |
1099 | if (Ustrstr(cbinfo->certificate, US"tls_sni") || |
1100 | Ustrstr(cbinfo->certificate, US"tls_in_sni") || | |
1101 | Ustrstr(cbinfo->certificate, US"tls_out_sni") | |
1102 | ) | |
1103 | reexpand_tls_files_for_sni = TRUE; | |
7be682ca | 1104 | |
cf0c6164 | 1105 | if (!expand_check(cbinfo->certificate, US"tls_certificate", &expanded, errstr)) |
23bb6982 JH |
1106 | return DEFER; |
1107 | ||
ba86e143 JH |
1108 | if (expanded) |
1109 | if (cbinfo->is_server) | |
1110 | { | |
1111 | const uschar * file_list = expanded; | |
1112 | int sep = 0; | |
1113 | uschar * file; | |
1114 | ||
1115 | while (file = string_nextinlist(&file_list, &sep, NULL, 0)) | |
1116 | if ((err = tls_add_certfile(sctx, cbinfo, file, errstr))) | |
1117 | return err; | |
1118 | } | |
1119 | else /* would there ever be a need for multiple client certs? */ | |
1120 | if ((err = tls_add_certfile(sctx, cbinfo, expanded, errstr))) | |
1121 | return err; | |
7be682ca | 1122 | |
23bb6982 | 1123 | if (cbinfo->privatekey != NULL && |
cf0c6164 | 1124 | !expand_check(cbinfo->privatekey, US"tls_privatekey", &expanded, errstr)) |
23bb6982 | 1125 | return DEFER; |
7be682ca | 1126 | |
23bb6982 JH |
1127 | /* If expansion was forced to fail, key_expanded will be NULL. If the result |
1128 | of the expansion is an empty string, ignore it also, and assume the private | |
1129 | key is in the same file as the certificate. */ | |
1130 | ||
1131 | if (expanded && *expanded) | |
ba86e143 JH |
1132 | if (cbinfo->is_server) |
1133 | { | |
1134 | const uschar * file_list = expanded; | |
1135 | int sep = 0; | |
1136 | uschar * file; | |
1137 | ||
1138 | while (file = string_nextinlist(&file_list, &sep, NULL, 0)) | |
1139 | if ((err = tls_add_pkeyfile(sctx, cbinfo, file, errstr))) | |
1140 | return err; | |
1141 | } | |
1142 | else /* would there ever be a need for multiple client certs? */ | |
1143 | if ((err = tls_add_pkeyfile(sctx, cbinfo, expanded, errstr))) | |
1144 | return err; | |
7be682ca PP |
1145 | } |
1146 | ||
f2de3a33 | 1147 | #ifndef DISABLE_OCSP |
f40d5be3 | 1148 | if (cbinfo->is_server && cbinfo->u_ocsp.server.file) |
3f7eeb86 | 1149 | { |
47195144 | 1150 | /*XXX stack*/ |
cf0c6164 | 1151 | if (!expand_check(cbinfo->u_ocsp.server.file, US"tls_ocsp_file", &expanded, errstr)) |
3f7eeb86 PP |
1152 | return DEFER; |
1153 | ||
f40d5be3 | 1154 | if (expanded && *expanded) |
3f7eeb86 PP |
1155 | { |
1156 | DEBUG(D_tls) debug_printf("tls_ocsp_file %s\n", expanded); | |
f40d5be3 JH |
1157 | if ( cbinfo->u_ocsp.server.file_expanded |
1158 | && (Ustrcmp(expanded, cbinfo->u_ocsp.server.file_expanded) == 0)) | |
3f7eeb86 | 1159 | { |
f40d5be3 JH |
1160 | DEBUG(D_tls) debug_printf(" - value unchanged, using existing values\n"); |
1161 | } | |
1162 | else | |
f40d5be3 | 1163 | ocsp_load_response(sctx, cbinfo, expanded); |
3f7eeb86 PP |
1164 | } |
1165 | } | |
1166 | #endif | |
1167 | ||
7be682ca PP |
1168 | return OK; |
1169 | } | |
1170 | ||
1171 | ||
1172 | ||
1173 | ||
1174 | /************************************************* | |
1175 | * Callback to handle SNI * | |
1176 | *************************************************/ | |
1177 | ||
1178 | /* Called when acting as server during the TLS session setup if a Server Name | |
1179 | Indication extension was sent by the client. | |
1180 | ||
1181 | API documentation is OpenSSL s_server.c implementation. | |
1182 | ||
1183 | Arguments: | |
1184 | s SSL* of the current session | |
1185 | ad unknown (part of OpenSSL API) (unused) | |
1186 | arg Callback of "our" registered data | |
1187 | ||
1188 | Returns: SSL_TLSEXT_ERR_{OK,ALERT_WARNING,ALERT_FATAL,NOACK} | |
1189 | */ | |
1190 | ||
3bcbbbe2 | 1191 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
7be682ca PP |
1192 | static int |
1193 | tls_servername_cb(SSL *s, int *ad ARG_UNUSED, void *arg) | |
1194 | { | |
1195 | const char *servername = SSL_get_servername(s, TLSEXT_NAMETYPE_host_name); | |
3f7eeb86 | 1196 | tls_ext_ctx_cb *cbinfo = (tls_ext_ctx_cb *) arg; |
7be682ca | 1197 | int rc; |
3f0945ff | 1198 | int old_pool = store_pool; |
cf0c6164 | 1199 | uschar * dummy_errstr; |
7be682ca PP |
1200 | |
1201 | if (!servername) | |
1202 | return SSL_TLSEXT_ERR_OK; | |
1203 | ||
3f0945ff | 1204 | DEBUG(D_tls) debug_printf("Received TLS SNI \"%s\"%s\n", servername, |
7be682ca PP |
1205 | reexpand_tls_files_for_sni ? "" : " (unused for certificate selection)"); |
1206 | ||
1207 | /* Make the extension value available for expansion */ | |
3f0945ff | 1208 | store_pool = POOL_PERM; |
817d9f57 | 1209 | tls_in.sni = string_copy(US servername); |
3f0945ff | 1210 | store_pool = old_pool; |
7be682ca PP |
1211 | |
1212 | if (!reexpand_tls_files_for_sni) | |
1213 | return SSL_TLSEXT_ERR_OK; | |
1214 | ||
1215 | /* Can't find an SSL_CTX_clone() or equivalent, so we do it manually; | |
1216 | not confident that memcpy wouldn't break some internal reference counting. | |
1217 | Especially since there's a references struct member, which would be off. */ | |
1218 | ||
0df4ab80 | 1219 | if (!(server_sni = SSL_CTX_new(SSLv23_server_method()))) |
7be682ca PP |
1220 | { |
1221 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
1222 | DEBUG(D_tls) debug_printf("SSL_CTX_new() failed: %s\n", ssl_errstring); | |
1223 | return SSL_TLSEXT_ERR_NOACK; | |
1224 | } | |
1225 | ||
1226 | /* Not sure how many of these are actually needed, since SSL object | |
1227 | already exists. Might even need this selfsame callback, for reneg? */ | |
1228 | ||
817d9f57 JH |
1229 | SSL_CTX_set_info_callback(server_sni, SSL_CTX_get_info_callback(server_ctx)); |
1230 | SSL_CTX_set_mode(server_sni, SSL_CTX_get_mode(server_ctx)); | |
1231 | SSL_CTX_set_options(server_sni, SSL_CTX_get_options(server_ctx)); | |
1232 | SSL_CTX_set_timeout(server_sni, SSL_CTX_get_timeout(server_ctx)); | |
1233 | SSL_CTX_set_tlsext_servername_callback(server_sni, tls_servername_cb); | |
1234 | SSL_CTX_set_tlsext_servername_arg(server_sni, cbinfo); | |
038597d2 | 1235 | |
cf0c6164 JH |
1236 | if ( !init_dh(server_sni, cbinfo->dhparam, NULL, &dummy_errstr) |
1237 | || !init_ecdh(server_sni, NULL, &dummy_errstr) | |
038597d2 PP |
1238 | ) |
1239 | return SSL_TLSEXT_ERR_NOACK; | |
1240 | ||
7be682ca | 1241 | if (cbinfo->server_cipher_list) |
817d9f57 | 1242 | SSL_CTX_set_cipher_list(server_sni, CS cbinfo->server_cipher_list); |
f2de3a33 | 1243 | #ifndef DISABLE_OCSP |
f5d78688 | 1244 | if (cbinfo->u_ocsp.server.file) |
3f7eeb86 | 1245 | { |
f5d78688 | 1246 | SSL_CTX_set_tlsext_status_cb(server_sni, tls_server_stapling_cb); |
14c7b357 | 1247 | SSL_CTX_set_tlsext_status_arg(server_sni, cbinfo); |
3f7eeb86 PP |
1248 | } |
1249 | #endif | |
7be682ca | 1250 | |
c3033f13 | 1251 | if ((rc = setup_certs(server_sni, tls_verify_certificates, tls_crl, NULL, FALSE, |
cf0c6164 | 1252 | verify_callback_server, &dummy_errstr)) != OK) |
c3033f13 | 1253 | return SSL_TLSEXT_ERR_NOACK; |
7be682ca | 1254 | |
3f7eeb86 PP |
1255 | /* do this after setup_certs, because this can require the certs for verifying |
1256 | OCSP information. */ | |
cf0c6164 | 1257 | if ((rc = tls_expand_session_files(server_sni, cbinfo, &dummy_errstr)) != OK) |
0df4ab80 | 1258 | return SSL_TLSEXT_ERR_NOACK; |
a799883d | 1259 | |
7be682ca | 1260 | DEBUG(D_tls) debug_printf("Switching SSL context.\n"); |
817d9f57 | 1261 | SSL_set_SSL_CTX(s, server_sni); |
7be682ca PP |
1262 | |
1263 | return SSL_TLSEXT_ERR_OK; | |
1264 | } | |
3bcbbbe2 | 1265 | #endif /* EXIM_HAVE_OPENSSL_TLSEXT */ |
7be682ca PP |
1266 | |
1267 | ||
1268 | ||
1269 | ||
f2de3a33 | 1270 | #ifndef DISABLE_OCSP |
f5d78688 | 1271 | |
3f7eeb86 PP |
1272 | /************************************************* |
1273 | * Callback to handle OCSP Stapling * | |
1274 | *************************************************/ | |
1275 | ||
1276 | /* Called when acting as server during the TLS session setup if the client | |
1277 | requests OCSP information with a Certificate Status Request. | |
1278 | ||
1279 | Documentation via openssl s_server.c and the Apache patch from the OpenSSL | |
1280 | project. | |
1281 | ||
1282 | */ | |
1283 | ||
1284 | static int | |
f5d78688 | 1285 | tls_server_stapling_cb(SSL *s, void *arg) |
3f7eeb86 PP |
1286 | { |
1287 | const tls_ext_ctx_cb *cbinfo = (tls_ext_ctx_cb *) arg; | |
47195144 | 1288 | uschar *response_der; /*XXX blob */ |
3f7eeb86 PP |
1289 | int response_der_len; |
1290 | ||
47195144 JH |
1291 | /*XXX stack: use SSL_get_certificate() to see which cert; from that work |
1292 | out which ocsp blob to send. Unfortunately, SSL_get_certificate is known | |
1293 | buggy in current OpenSSL; it returns the last cert loaded always rather than | |
1294 | the one actually presented. So we can't support a stack of OCSP proofs at | |
1295 | this time. */ | |
1296 | ||
af4a1bca | 1297 | DEBUG(D_tls) |
b3ef41c9 | 1298 | debug_printf("Received TLS status request (OCSP stapling); %s response\n", |
f5d78688 JH |
1299 | cbinfo->u_ocsp.server.response ? "have" : "lack"); |
1300 | ||
44662487 | 1301 | tls_in.ocsp = OCSP_NOT_RESP; |
f5d78688 | 1302 | if (!cbinfo->u_ocsp.server.response) |
3f7eeb86 PP |
1303 | return SSL_TLSEXT_ERR_NOACK; |
1304 | ||
1305 | response_der = NULL; | |
47195144 | 1306 | response_der_len = i2d_OCSP_RESPONSE(cbinfo->u_ocsp.server.response, /*XXX stack*/ |
44662487 | 1307 | &response_der); |
3f7eeb86 PP |
1308 | if (response_der_len <= 0) |
1309 | return SSL_TLSEXT_ERR_NOACK; | |
1310 | ||
5e55c7a9 | 1311 | SSL_set_tlsext_status_ocsp_resp(server_ssl, response_der, response_der_len); |
44662487 | 1312 | tls_in.ocsp = OCSP_VFIED; |
3f7eeb86 PP |
1313 | return SSL_TLSEXT_ERR_OK; |
1314 | } | |
1315 | ||
3f7eeb86 | 1316 | |
f5d78688 JH |
1317 | static void |
1318 | time_print(BIO * bp, const char * str, ASN1_GENERALIZEDTIME * time) | |
1319 | { | |
1320 | BIO_printf(bp, "\t%s: ", str); | |
1321 | ASN1_GENERALIZEDTIME_print(bp, time); | |
1322 | BIO_puts(bp, "\n"); | |
1323 | } | |
1324 | ||
1325 | static int | |
1326 | tls_client_stapling_cb(SSL *s, void *arg) | |
1327 | { | |
1328 | tls_ext_ctx_cb * cbinfo = arg; | |
1329 | const unsigned char * p; | |
1330 | int len; | |
1331 | OCSP_RESPONSE * rsp; | |
1332 | OCSP_BASICRESP * bs; | |
1333 | int i; | |
1334 | ||
1335 | DEBUG(D_tls) debug_printf("Received TLS status response (OCSP stapling):"); | |
1336 | len = SSL_get_tlsext_status_ocsp_resp(s, &p); | |
1337 | if(!p) | |
1338 | { | |
44662487 | 1339 | /* Expect this when we requested ocsp but got none */ |
6c6d6e48 | 1340 | if (cbinfo->u_ocsp.client.verify_required && LOGGING(tls_cipher)) |
44662487 | 1341 | log_write(0, LOG_MAIN, "Received TLS status callback, null content"); |
f5d78688 JH |
1342 | else |
1343 | DEBUG(D_tls) debug_printf(" null\n"); | |
44662487 | 1344 | return cbinfo->u_ocsp.client.verify_required ? 0 : 1; |
f5d78688 | 1345 | } |
018058b2 | 1346 | |
f5d78688 JH |
1347 | if(!(rsp = d2i_OCSP_RESPONSE(NULL, &p, len))) |
1348 | { | |
018058b2 | 1349 | tls_out.ocsp = OCSP_FAILED; |
6c6d6e48 | 1350 | if (LOGGING(tls_cipher)) |
1eca31ca | 1351 | log_write(0, LOG_MAIN, "Received TLS cert status response, parse error"); |
f5d78688 JH |
1352 | else |
1353 | DEBUG(D_tls) debug_printf(" parse error\n"); | |
1354 | return 0; | |
1355 | } | |
1356 | ||
1357 | if(!(bs = OCSP_response_get1_basic(rsp))) | |
1358 | { | |
018058b2 | 1359 | tls_out.ocsp = OCSP_FAILED; |
6c6d6e48 | 1360 | if (LOGGING(tls_cipher)) |
1eca31ca | 1361 | log_write(0, LOG_MAIN, "Received TLS cert status response, error parsing response"); |
f5d78688 JH |
1362 | else |
1363 | DEBUG(D_tls) debug_printf(" error parsing response\n"); | |
1364 | OCSP_RESPONSE_free(rsp); | |
1365 | return 0; | |
1366 | } | |
1367 | ||
1368 | /* We'd check the nonce here if we'd put one in the request. */ | |
1369 | /* However that would defeat cacheability on the server so we don't. */ | |
1370 | ||
f5d78688 JH |
1371 | /* This section of code reworked from OpenSSL apps source; |
1372 | The OpenSSL Project retains copyright: | |
1373 | Copyright (c) 1999 The OpenSSL Project. All rights reserved. | |
1374 | */ | |
1375 | { | |
1376 | BIO * bp = NULL; | |
f5d78688 JH |
1377 | int status, reason; |
1378 | ASN1_GENERALIZEDTIME *rev, *thisupd, *nextupd; | |
1379 | ||
57887ecc | 1380 | DEBUG(D_tls) bp = BIO_new_fp(debug_file, BIO_NOCLOSE); |
f5d78688 JH |
1381 | |
1382 | /*OCSP_RESPONSE_print(bp, rsp, 0); extreme debug: stapling content */ | |
1383 | ||
1384 | /* Use the chain that verified the server cert to verify the stapled info */ | |
1385 | /* DEBUG(D_tls) x509_store_dump_cert_s_names(cbinfo->u_ocsp.client.verify_store); */ | |
1386 | ||
c3033f13 | 1387 | if ((i = OCSP_basic_verify(bs, cbinfo->verify_stack, |
44662487 | 1388 | cbinfo->u_ocsp.client.verify_store, 0)) <= 0) |
f5d78688 | 1389 | { |
018058b2 | 1390 | tls_out.ocsp = OCSP_FAILED; |
57887ecc JH |
1391 | if (LOGGING(tls_cipher)) log_write(0, LOG_MAIN, |
1392 | "Received TLS cert status response, itself unverifiable: %s", | |
1393 | ERR_reason_error_string(ERR_peek_error())); | |
f5d78688 JH |
1394 | BIO_printf(bp, "OCSP response verify failure\n"); |
1395 | ERR_print_errors(bp); | |
57887ecc | 1396 | OCSP_RESPONSE_print(bp, rsp, 0); |
c8dfb21d | 1397 | goto failed; |
f5d78688 JH |
1398 | } |
1399 | ||
1400 | BIO_printf(bp, "OCSP response well-formed and signed OK\n"); | |
1401 | ||
c8dfb21d JH |
1402 | /*XXX So we have a good stapled OCSP status. How do we know |
1403 | it is for the cert of interest? OpenSSL 1.1.0 has a routine | |
1404 | OCSP_resp_find_status() which matches on a cert id, which presumably | |
1405 | we should use. Making an id needs OCSP_cert_id_new(), which takes | |
1406 | issuerName, issuerKey, serialNumber. Are they all in the cert? | |
1407 | ||
1408 | For now, carry on blindly accepting the resp. */ | |
1409 | ||
f5d78688 | 1410 | { |
f5d78688 JH |
1411 | OCSP_SINGLERESP * single; |
1412 | ||
c8dfb21d JH |
1413 | #ifdef EXIM_HAVE_OCSP_RESP_COUNT |
1414 | if (OCSP_resp_count(bs) != 1) | |
1415 | #else | |
1416 | STACK_OF(OCSP_SINGLERESP) * sresp = bs->tbsResponseData->responses; | |
f5d78688 | 1417 | if (sk_OCSP_SINGLERESP_num(sresp) != 1) |
c8dfb21d | 1418 | #endif |
f5d78688 | 1419 | { |
018058b2 | 1420 | tls_out.ocsp = OCSP_FAILED; |
44662487 JH |
1421 | log_write(0, LOG_MAIN, "OCSP stapling " |
1422 | "with multiple responses not handled"); | |
c8dfb21d | 1423 | goto failed; |
f5d78688 JH |
1424 | } |
1425 | single = OCSP_resp_get0(bs, 0); | |
44662487 JH |
1426 | status = OCSP_single_get0_status(single, &reason, &rev, |
1427 | &thisupd, &nextupd); | |
f5d78688 JH |
1428 | } |
1429 | ||
f5d78688 JH |
1430 | DEBUG(D_tls) time_print(bp, "This OCSP Update", thisupd); |
1431 | DEBUG(D_tls) if(nextupd) time_print(bp, "Next OCSP Update", nextupd); | |
44662487 JH |
1432 | if (!OCSP_check_validity(thisupd, nextupd, |
1433 | EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE)) | |
f5d78688 | 1434 | { |
018058b2 | 1435 | tls_out.ocsp = OCSP_FAILED; |
f5d78688 JH |
1436 | DEBUG(D_tls) ERR_print_errors(bp); |
1437 | log_write(0, LOG_MAIN, "Server OSCP dates invalid"); | |
f5d78688 | 1438 | } |
44662487 | 1439 | else |
f5d78688 | 1440 | { |
44662487 JH |
1441 | DEBUG(D_tls) BIO_printf(bp, "Certificate status: %s\n", |
1442 | OCSP_cert_status_str(status)); | |
1443 | switch(status) | |
1444 | { | |
1445 | case V_OCSP_CERTSTATUS_GOOD: | |
44662487 | 1446 | tls_out.ocsp = OCSP_VFIED; |
018058b2 | 1447 | i = 1; |
c8dfb21d | 1448 | goto good; |
44662487 | 1449 | case V_OCSP_CERTSTATUS_REVOKED: |
018058b2 | 1450 | tls_out.ocsp = OCSP_FAILED; |
44662487 JH |
1451 | log_write(0, LOG_MAIN, "Server certificate revoked%s%s", |
1452 | reason != -1 ? "; reason: " : "", | |
1453 | reason != -1 ? OCSP_crl_reason_str(reason) : ""); | |
1454 | DEBUG(D_tls) time_print(bp, "Revocation Time", rev); | |
44662487 JH |
1455 | break; |
1456 | default: | |
018058b2 | 1457 | tls_out.ocsp = OCSP_FAILED; |
44662487 JH |
1458 | log_write(0, LOG_MAIN, |
1459 | "Server certificate status unknown, in OCSP stapling"); | |
44662487 JH |
1460 | break; |
1461 | } | |
f5d78688 | 1462 | } |
c8dfb21d JH |
1463 | failed: |
1464 | i = cbinfo->u_ocsp.client.verify_required ? 0 : 1; | |
1465 | good: | |
f5d78688 JH |
1466 | BIO_free(bp); |
1467 | } | |
1468 | ||
1469 | OCSP_RESPONSE_free(rsp); | |
1470 | return i; | |
1471 | } | |
f2de3a33 | 1472 | #endif /*!DISABLE_OCSP*/ |
3f7eeb86 PP |
1473 | |
1474 | ||
059ec3d9 PH |
1475 | /************************************************* |
1476 | * Initialize for TLS * | |
1477 | *************************************************/ | |
1478 | ||
e51c7be2 JH |
1479 | /* Called from both server and client code, to do preliminary initialization |
1480 | of the library. We allocate and return a context structure. | |
059ec3d9 PH |
1481 | |
1482 | Arguments: | |
946ecbe0 | 1483 | ctxp returned SSL context |
059ec3d9 PH |
1484 | host connected host, if client; NULL if server |
1485 | dhparam DH parameter file | |
1486 | certificate certificate file | |
1487 | privatekey private key | |
f5d78688 | 1488 | ocsp_file file of stapling info (server); flag for require ocsp (client) |
059ec3d9 | 1489 | addr address if client; NULL if server (for some randomness) |
946ecbe0 | 1490 | cbp place to put allocated callback context |
cf0c6164 | 1491 | errstr error string pointer |
059ec3d9 PH |
1492 | |
1493 | Returns: OK/DEFER/FAIL | |
1494 | */ | |
1495 | ||
1496 | static int | |
817d9f57 | 1497 | tls_init(SSL_CTX **ctxp, host_item *host, uschar *dhparam, uschar *certificate, |
3f7eeb86 | 1498 | uschar *privatekey, |
f2de3a33 | 1499 | #ifndef DISABLE_OCSP |
47195144 | 1500 | uschar *ocsp_file, /*XXX stack, in server*/ |
3f7eeb86 | 1501 | #endif |
cf0c6164 | 1502 | address_item *addr, tls_ext_ctx_cb ** cbp, uschar ** errstr) |
059ec3d9 | 1503 | { |
7006ee24 | 1504 | SSL_CTX * ctx; |
77bb000f | 1505 | long init_options; |
7be682ca | 1506 | int rc; |
a7538db1 | 1507 | tls_ext_ctx_cb * cbinfo; |
7be682ca PP |
1508 | |
1509 | cbinfo = store_malloc(sizeof(tls_ext_ctx_cb)); | |
1510 | cbinfo->certificate = certificate; | |
1511 | cbinfo->privatekey = privatekey; | |
a6510420 | 1512 | cbinfo->is_server = host==NULL; |
f2de3a33 | 1513 | #ifndef DISABLE_OCSP |
c3033f13 | 1514 | cbinfo->verify_stack = NULL; |
a6510420 | 1515 | if (!host) |
f5d78688 JH |
1516 | { |
1517 | cbinfo->u_ocsp.server.file = ocsp_file; | |
1518 | cbinfo->u_ocsp.server.file_expanded = NULL; | |
1519 | cbinfo->u_ocsp.server.response = NULL; | |
1520 | } | |
1521 | else | |
1522 | cbinfo->u_ocsp.client.verify_store = NULL; | |
3f7eeb86 | 1523 | #endif |
7be682ca | 1524 | cbinfo->dhparam = dhparam; |
0df4ab80 | 1525 | cbinfo->server_cipher_list = NULL; |
7be682ca | 1526 | cbinfo->host = host; |
0cbf2b82 | 1527 | #ifndef DISABLE_EVENT |
a7538db1 JH |
1528 | cbinfo->event_action = NULL; |
1529 | #endif | |
77bb000f | 1530 | |
059ec3d9 PH |
1531 | SSL_load_error_strings(); /* basic set up */ |
1532 | OpenSSL_add_ssl_algorithms(); | |
1533 | ||
c8dfb21d | 1534 | #ifdef EXIM_HAVE_SHA256 |
77bb000f | 1535 | /* SHA256 is becoming ever more popular. This makes sure it gets added to the |
a0475b69 TK |
1536 | list of available digests. */ |
1537 | EVP_add_digest(EVP_sha256()); | |
cf1ef1a9 | 1538 | #endif |
a0475b69 | 1539 | |
f0f5a555 PP |
1540 | /* Create a context. |
1541 | The OpenSSL docs in 1.0.1b have not been updated to clarify TLS variant | |
1542 | negotiation in the different methods; as far as I can tell, the only | |
1543 | *_{server,client}_method which allows negotiation is SSLv23, which exists even | |
1544 | when OpenSSL is built without SSLv2 support. | |
1545 | By disabling with openssl_options, we can let admins re-enable with the | |
1546 | existing knob. */ | |
059ec3d9 | 1547 | |
7006ee24 JH |
1548 | if (!(ctx = SSL_CTX_new(host ? SSLv23_client_method() : SSLv23_server_method()))) |
1549 | return tls_error(US"SSL_CTX_new", host, NULL, errstr); | |
059ec3d9 PH |
1550 | |
1551 | /* It turns out that we need to seed the random number generator this early in | |
1552 | order to get the full complement of ciphers to work. It took me roughly a day | |
1553 | of work to discover this by experiment. | |
1554 | ||
1555 | On systems that have /dev/urandom, SSL may automatically seed itself from | |
1556 | there. Otherwise, we have to make something up as best we can. Double check | |
1557 | afterwards. */ | |
1558 | ||
1559 | if (!RAND_status()) | |
1560 | { | |
1561 | randstuff r; | |
9e3331ea | 1562 | gettimeofday(&r.tv, NULL); |
059ec3d9 PH |
1563 | r.p = getpid(); |
1564 | ||
5903c6ff JH |
1565 | RAND_seed(US (&r), sizeof(r)); |
1566 | RAND_seed(US big_buffer, big_buffer_size); | |
1567 | if (addr != NULL) RAND_seed(US addr, sizeof(addr)); | |
059ec3d9 PH |
1568 | |
1569 | if (!RAND_status()) | |
7199e1ee | 1570 | return tls_error(US"RAND_status", host, |
cf0c6164 | 1571 | US"unable to seed random number generator", errstr); |
059ec3d9 PH |
1572 | } |
1573 | ||
1574 | /* Set up the information callback, which outputs if debugging is at a suitable | |
1575 | level. */ | |
1576 | ||
7006ee24 | 1577 | DEBUG(D_tls) SSL_CTX_set_info_callback(ctx, (void (*)())info_callback); |
059ec3d9 | 1578 | |
c80c5570 | 1579 | /* Automatically re-try reads/writes after renegotiation. */ |
7006ee24 | 1580 | (void) SSL_CTX_set_mode(ctx, SSL_MODE_AUTO_RETRY); |
c80c5570 | 1581 | |
77bb000f PP |
1582 | /* Apply administrator-supplied work-arounds. |
1583 | Historically we applied just one requested option, | |
1584 | SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS, but when bug 994 requested a second, we | |
1585 | moved to an administrator-controlled list of options to specify and | |
1586 | grandfathered in the first one as the default value for "openssl_options". | |
059ec3d9 | 1587 | |
77bb000f PP |
1588 | No OpenSSL version number checks: the options we accept depend upon the |
1589 | availability of the option value macros from OpenSSL. */ | |
059ec3d9 | 1590 | |
7006ee24 | 1591 | if (!tls_openssl_options_parse(openssl_options, &init_options)) |
cf0c6164 | 1592 | return tls_error(US"openssl_options parsing failed", host, NULL, errstr); |
77bb000f PP |
1593 | |
1594 | if (init_options) | |
1595 | { | |
1596 | DEBUG(D_tls) debug_printf("setting SSL CTX options: %#lx\n", init_options); | |
7006ee24 | 1597 | if (!(SSL_CTX_set_options(ctx, init_options))) |
77bb000f | 1598 | return tls_error(string_sprintf( |
cf0c6164 | 1599 | "SSL_CTX_set_option(%#lx)", init_options), host, NULL, errstr); |
77bb000f PP |
1600 | } |
1601 | else | |
1602 | DEBUG(D_tls) debug_printf("no SSL CTX options to set\n"); | |
059ec3d9 | 1603 | |
a28050f8 JH |
1604 | /* We'd like to disable session cache unconditionally, but foolish Outlook |
1605 | Express clients then give up the first TLS connection and make a second one | |
1606 | (which works). Only when there is an IMAP service on the same machine. | |
1607 | Presumably OE is trying to use the cache for A on B. Leave it enabled for | |
1608 | now, until we work out a decent way of presenting control to the config. It | |
1609 | will never be used because we use a new context every time. */ | |
1610 | #ifdef notdef | |
7006ee24 | 1611 | (void) SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF); |
a28050f8 | 1612 | #endif |
7006ee24 | 1613 | |
059ec3d9 | 1614 | /* Initialize with DH parameters if supplied */ |
10ca4f1c | 1615 | /* Initialize ECDH temp key parameter selection */ |
059ec3d9 | 1616 | |
7006ee24 JH |
1617 | if ( !init_dh(ctx, dhparam, host, errstr) |
1618 | || !init_ecdh(ctx, host, errstr) | |
038597d2 PP |
1619 | ) |
1620 | return DEFER; | |
059ec3d9 | 1621 | |
3f7eeb86 | 1622 | /* Set up certificate and key (and perhaps OCSP info) */ |
059ec3d9 | 1623 | |
7006ee24 | 1624 | if ((rc = tls_expand_session_files(ctx, cbinfo, errstr)) != OK) |
23bb6982 | 1625 | return rc; |
c91535f3 | 1626 | |
c3033f13 JH |
1627 | /* If we need to handle SNI or OCSP, do so */ |
1628 | ||
3bcbbbe2 | 1629 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
c3033f13 JH |
1630 | # ifndef DISABLE_OCSP |
1631 | if (!(cbinfo->verify_stack = sk_X509_new_null())) | |
1632 | { | |
1633 | DEBUG(D_tls) debug_printf("failed to create stack for stapling verify\n"); | |
1634 | return FAIL; | |
1635 | } | |
1636 | # endif | |
1637 | ||
f5d78688 | 1638 | if (host == NULL) /* server */ |
3f0945ff | 1639 | { |
f2de3a33 | 1640 | # ifndef DISABLE_OCSP |
f5d78688 | 1641 | /* We check u_ocsp.server.file, not server.response, because we care about if |
3f7eeb86 PP |
1642 | the option exists, not what the current expansion might be, as SNI might |
1643 | change the certificate and OCSP file in use between now and the time the | |
1644 | callback is invoked. */ | |
f5d78688 | 1645 | if (cbinfo->u_ocsp.server.file) |
3f7eeb86 | 1646 | { |
7006ee24 JH |
1647 | SSL_CTX_set_tlsext_status_cb(ctx, tls_server_stapling_cb); |
1648 | SSL_CTX_set_tlsext_status_arg(ctx, cbinfo); | |
3f7eeb86 | 1649 | } |
f5d78688 | 1650 | # endif |
3f0945ff PP |
1651 | /* We always do this, so that $tls_sni is available even if not used in |
1652 | tls_certificate */ | |
7006ee24 JH |
1653 | SSL_CTX_set_tlsext_servername_callback(ctx, tls_servername_cb); |
1654 | SSL_CTX_set_tlsext_servername_arg(ctx, cbinfo); | |
3f0945ff | 1655 | } |
f2de3a33 | 1656 | # ifndef DISABLE_OCSP |
f5d78688 JH |
1657 | else /* client */ |
1658 | if(ocsp_file) /* wanting stapling */ | |
1659 | { | |
1660 | if (!(cbinfo->u_ocsp.client.verify_store = X509_STORE_new())) | |
1661 | { | |
1662 | DEBUG(D_tls) debug_printf("failed to create store for stapling verify\n"); | |
1663 | return FAIL; | |
1664 | } | |
7006ee24 JH |
1665 | SSL_CTX_set_tlsext_status_cb(ctx, tls_client_stapling_cb); |
1666 | SSL_CTX_set_tlsext_status_arg(ctx, cbinfo); | |
f5d78688 JH |
1667 | } |
1668 | # endif | |
7be682ca | 1669 | #endif |
059ec3d9 | 1670 | |
e51c7be2 | 1671 | cbinfo->verify_cert_hostnames = NULL; |
e51c7be2 | 1672 | |
c8dfb21d | 1673 | #ifdef EXIM_HAVE_EPHEM_RSA_KEX |
059ec3d9 | 1674 | /* Set up the RSA callback */ |
7006ee24 | 1675 | SSL_CTX_set_tmp_rsa_callback(ctx, rsa_callback); |
c8dfb21d | 1676 | #endif |
059ec3d9 PH |
1677 | |
1678 | /* Finally, set the timeout, and we are done */ | |
1679 | ||
7006ee24 | 1680 | SSL_CTX_set_timeout(ctx, ssl_session_timeout); |
059ec3d9 | 1681 | DEBUG(D_tls) debug_printf("Initialized TLS\n"); |
7be682ca | 1682 | |
817d9f57 | 1683 | *cbp = cbinfo; |
7006ee24 | 1684 | *ctxp = ctx; |
7be682ca | 1685 | |
059ec3d9 PH |
1686 | return OK; |
1687 | } | |
1688 | ||
1689 | ||
1690 | ||
1691 | ||
1692 | /************************************************* | |
1693 | * Get name of cipher in use * | |
1694 | *************************************************/ | |
1695 | ||
817d9f57 | 1696 | /* |
059ec3d9 | 1697 | Argument: pointer to an SSL structure for the connection |
817d9f57 JH |
1698 | buffer to use for answer |
1699 | size of buffer | |
1700 | pointer to number of bits for cipher | |
059ec3d9 PH |
1701 | Returns: nothing |
1702 | */ | |
1703 | ||
1704 | static void | |
817d9f57 | 1705 | construct_cipher_name(SSL *ssl, uschar *cipherbuf, int bsize, int *bits) |
059ec3d9 | 1706 | { |
57b3a7f5 PP |
1707 | /* With OpenSSL 1.0.0a, this needs to be const but the documentation doesn't |
1708 | yet reflect that. It should be a safe change anyway, even 0.9.8 versions have | |
1709 | the accessor functions use const in the prototype. */ | |
1710 | const SSL_CIPHER *c; | |
d9784128 | 1711 | const uschar *ver; |
059ec3d9 | 1712 | |
d9784128 | 1713 | ver = (const uschar *)SSL_get_version(ssl); |
059ec3d9 | 1714 | |
57b3a7f5 | 1715 | c = (const SSL_CIPHER *) SSL_get_current_cipher(ssl); |
817d9f57 | 1716 | SSL_CIPHER_get_bits(c, bits); |
059ec3d9 | 1717 | |
817d9f57 JH |
1718 | string_format(cipherbuf, bsize, "%s:%s:%u", ver, |
1719 | SSL_CIPHER_get_name(c), *bits); | |
059ec3d9 PH |
1720 | |
1721 | DEBUG(D_tls) debug_printf("Cipher: %s\n", cipherbuf); | |
1722 | } | |
1723 | ||
1724 | ||
f69979cf JH |
1725 | static void |
1726 | peer_cert(SSL * ssl, tls_support * tlsp, uschar * peerdn, unsigned bsize) | |
1727 | { | |
1728 | /*XXX we might consider a list-of-certs variable for the cert chain. | |
1729 | SSL_get_peer_cert_chain(SSL*). We'd need a new variable type and support | |
1730 | in list-handling functions, also consider the difference between the entire | |
1731 | chain and the elements sent by the peer. */ | |
1732 | ||
1733 | /* Will have already noted peercert on a verify fail; possibly not the leaf */ | |
1734 | if (!tlsp->peercert) | |
1735 | tlsp->peercert = SSL_get_peer_certificate(ssl); | |
1736 | /* Beware anonymous ciphers which lead to server_cert being NULL */ | |
1737 | if (tlsp->peercert) | |
1738 | { | |
1739 | X509_NAME_oneline(X509_get_subject_name(tlsp->peercert), CS peerdn, bsize); | |
1740 | peerdn[bsize-1] = '\0'; | |
1741 | tlsp->peerdn = peerdn; /*XXX a static buffer... */ | |
1742 | } | |
1743 | else | |
1744 | tlsp->peerdn = NULL; | |
1745 | } | |
1746 | ||
1747 | ||
059ec3d9 PH |
1748 | |
1749 | ||
1750 | ||
1751 | /************************************************* | |
1752 | * Set up for verifying certificates * | |
1753 | *************************************************/ | |
1754 | ||
0e8aed8a | 1755 | #ifndef DISABLE_OCSP |
c3033f13 JH |
1756 | /* Load certs from file, return TRUE on success */ |
1757 | ||
1758 | static BOOL | |
1759 | chain_from_pem_file(const uschar * file, STACK_OF(X509) * verify_stack) | |
1760 | { | |
1761 | BIO * bp; | |
1762 | X509 * x; | |
1763 | ||
dec766a1 WB |
1764 | while (sk_X509_num(verify_stack) > 0) |
1765 | X509_free(sk_X509_pop(verify_stack)); | |
1766 | ||
c3033f13 JH |
1767 | if (!(bp = BIO_new_file(CS file, "r"))) return FALSE; |
1768 | while ((x = PEM_read_bio_X509(bp, NULL, 0, NULL))) | |
1769 | sk_X509_push(verify_stack, x); | |
1770 | BIO_free(bp); | |
1771 | return TRUE; | |
1772 | } | |
0e8aed8a | 1773 | #endif |
c3033f13 JH |
1774 | |
1775 | ||
1776 | ||
dec766a1 WB |
1777 | /* Called by both client and server startup; on the server possibly |
1778 | repeated after a Server Name Indication. | |
059ec3d9 PH |
1779 | |
1780 | Arguments: | |
7be682ca | 1781 | sctx SSL_CTX* to initialise |
059ec3d9 PH |
1782 | certs certs file or NULL |
1783 | crl CRL file or NULL | |
1784 | host NULL in a server; the remote host in a client | |
1785 | optional TRUE if called from a server for a host in tls_try_verify_hosts; | |
1786 | otherwise passed as FALSE | |
983207c1 | 1787 | cert_vfy_cb Callback function for certificate verification |
cf0c6164 | 1788 | errstr error string pointer |
059ec3d9 PH |
1789 | |
1790 | Returns: OK/DEFER/FAIL | |
1791 | */ | |
1792 | ||
1793 | static int | |
983207c1 | 1794 | setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host, BOOL optional, |
cf0c6164 | 1795 | int (*cert_vfy_cb)(int, X509_STORE_CTX *), uschar ** errstr) |
059ec3d9 PH |
1796 | { |
1797 | uschar *expcerts, *expcrl; | |
1798 | ||
cf0c6164 | 1799 | if (!expand_check(certs, US"tls_verify_certificates", &expcerts, errstr)) |
059ec3d9 | 1800 | return DEFER; |
57cc2785 | 1801 | DEBUG(D_tls) debug_printf("tls_verify_certificates: %s\n", expcerts); |
059ec3d9 | 1802 | |
10a831a3 | 1803 | if (expcerts && *expcerts) |
059ec3d9 | 1804 | { |
10a831a3 JH |
1805 | /* Tell the library to use its compiled-in location for the system default |
1806 | CA bundle. Then add the ones specified in the config, if any. */ | |
cb1d7830 | 1807 | |
10a831a3 | 1808 | if (!SSL_CTX_set_default_verify_paths(sctx)) |
cf0c6164 | 1809 | return tls_error(US"SSL_CTX_set_default_verify_paths", host, NULL, errstr); |
10a831a3 JH |
1810 | |
1811 | if (Ustrcmp(expcerts, "system") != 0) | |
059ec3d9 | 1812 | { |
cb1d7830 JH |
1813 | struct stat statbuf; |
1814 | ||
cb1d7830 JH |
1815 | if (Ustat(expcerts, &statbuf) < 0) |
1816 | { | |
1817 | log_write(0, LOG_MAIN|LOG_PANIC, | |
1818 | "failed to stat %s for certificates", expcerts); | |
1819 | return DEFER; | |
1820 | } | |
059ec3d9 | 1821 | else |
059ec3d9 | 1822 | { |
cb1d7830 JH |
1823 | uschar *file, *dir; |
1824 | if ((statbuf.st_mode & S_IFMT) == S_IFDIR) | |
1825 | { file = NULL; dir = expcerts; } | |
1826 | else | |
c3033f13 JH |
1827 | { |
1828 | file = expcerts; dir = NULL; | |
1829 | #ifndef DISABLE_OCSP | |
1830 | /* In the server if we will be offering an OCSP proof, load chain from | |
1831 | file for verifying the OCSP proof at load time. */ | |
1832 | ||
1833 | if ( !host | |
1834 | && statbuf.st_size > 0 | |
1835 | && server_static_cbinfo->u_ocsp.server.file | |
1836 | && !chain_from_pem_file(file, server_static_cbinfo->verify_stack) | |
1837 | ) | |
1838 | { | |
1839 | log_write(0, LOG_MAIN|LOG_PANIC, | |
57887ecc | 1840 | "failed to load cert chain from %s", file); |
c3033f13 JH |
1841 | return DEFER; |
1842 | } | |
1843 | #endif | |
1844 | } | |
cb1d7830 JH |
1845 | |
1846 | /* If a certificate file is empty, the next function fails with an | |
1847 | unhelpful error message. If we skip it, we get the correct behaviour (no | |
1848 | certificates are recognized, but the error message is still misleading (it | |
c3033f13 | 1849 | says no certificate was supplied). But this is better. */ |
cb1d7830 | 1850 | |
f2f2c91b JH |
1851 | if ( (!file || statbuf.st_size > 0) |
1852 | && !SSL_CTX_load_verify_locations(sctx, CS file, CS dir)) | |
cf0c6164 | 1853 | return tls_error(US"SSL_CTX_load_verify_locations", host, NULL, errstr); |
cb1d7830 JH |
1854 | |
1855 | /* Load the list of CAs for which we will accept certs, for sending | |
1856 | to the client. This is only for the one-file tls_verify_certificates | |
1857 | variant. | |
1858 | If a list isn't loaded into the server, but | |
1859 | some verify locations are set, the server end appears to make | |
4c04137d | 1860 | a wildcard request for client certs. |
10a831a3 | 1861 | Meanwhile, the client library as default behaviour *ignores* the list |
cb1d7830 JH |
1862 | we send over the wire - see man SSL_CTX_set_client_cert_cb. |
1863 | Because of this, and that the dir variant is likely only used for | |
1864 | the public-CA bundle (not for a private CA), not worth fixing. | |
1865 | */ | |
f2f2c91b | 1866 | if (file) |
cb1d7830 | 1867 | { |
2009ecca | 1868 | STACK_OF(X509_NAME) * names = SSL_load_client_CA_file(CS file); |
dec766a1 WB |
1869 | |
1870 | SSL_CTX_set_client_CA_list(sctx, names); | |
f2f2c91b | 1871 | DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", |
cb1d7830 | 1872 | sk_X509_NAME_num(names)); |
cb1d7830 | 1873 | } |
059ec3d9 PH |
1874 | } |
1875 | } | |
1876 | ||
1877 | /* Handle a certificate revocation list. */ | |
1878 | ||
10a831a3 | 1879 | #if OPENSSL_VERSION_NUMBER > 0x00907000L |
059ec3d9 | 1880 | |
8b417f2c | 1881 | /* This bit of code is now the version supplied by Lars Mainka. (I have |
10a831a3 | 1882 | merely reformatted it into the Exim code style.) |
8b417f2c | 1883 | |
10a831a3 JH |
1884 | "From here I changed the code to add support for multiple crl's |
1885 | in pem format in one file or to support hashed directory entries in | |
1886 | pem format instead of a file. This method now uses the library function | |
1887 | X509_STORE_load_locations to add the CRL location to the SSL context. | |
1888 | OpenSSL will then handle the verify against CA certs and CRLs by | |
1889 | itself in the verify callback." */ | |
8b417f2c | 1890 | |
cf0c6164 | 1891 | if (!expand_check(crl, US"tls_crl", &expcrl, errstr)) return DEFER; |
10a831a3 | 1892 | if (expcrl && *expcrl) |
059ec3d9 | 1893 | { |
8b417f2c PH |
1894 | struct stat statbufcrl; |
1895 | if (Ustat(expcrl, &statbufcrl) < 0) | |
1896 | { | |
1897 | log_write(0, LOG_MAIN|LOG_PANIC, | |
1898 | "failed to stat %s for certificates revocation lists", expcrl); | |
1899 | return DEFER; | |
1900 | } | |
1901 | else | |
059ec3d9 | 1902 | { |
8b417f2c PH |
1903 | /* is it a file or directory? */ |
1904 | uschar *file, *dir; | |
7be682ca | 1905 | X509_STORE *cvstore = SSL_CTX_get_cert_store(sctx); |
8b417f2c | 1906 | if ((statbufcrl.st_mode & S_IFMT) == S_IFDIR) |
059ec3d9 | 1907 | { |
8b417f2c PH |
1908 | file = NULL; |
1909 | dir = expcrl; | |
1910 | DEBUG(D_tls) debug_printf("SSL CRL value is a directory %s\n", dir); | |
059ec3d9 PH |
1911 | } |
1912 | else | |
1913 | { | |
8b417f2c PH |
1914 | file = expcrl; |
1915 | dir = NULL; | |
1916 | DEBUG(D_tls) debug_printf("SSL CRL value is a file %s\n", file); | |
059ec3d9 | 1917 | } |
8b417f2c | 1918 | if (X509_STORE_load_locations(cvstore, CS file, CS dir) == 0) |
cf0c6164 | 1919 | return tls_error(US"X509_STORE_load_locations", host, NULL, errstr); |
8b417f2c PH |
1920 | |
1921 | /* setting the flags to check against the complete crl chain */ | |
1922 | ||
1923 | X509_STORE_set_flags(cvstore, | |
1924 | X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL); | |
059ec3d9 | 1925 | } |
059ec3d9 PH |
1926 | } |
1927 | ||
10a831a3 | 1928 | #endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */ |
059ec3d9 PH |
1929 | |
1930 | /* If verification is optional, don't fail if no certificate */ | |
1931 | ||
7be682ca | 1932 | SSL_CTX_set_verify(sctx, |
059ec3d9 | 1933 | SSL_VERIFY_PEER | (optional? 0 : SSL_VERIFY_FAIL_IF_NO_PEER_CERT), |
983207c1 | 1934 | cert_vfy_cb); |
059ec3d9 PH |
1935 | } |
1936 | ||
1937 | return OK; | |
1938 | } | |
1939 | ||
1940 | ||
1941 | ||
1942 | /************************************************* | |
1943 | * Start a TLS session in a server * | |
1944 | *************************************************/ | |
1945 | ||
1946 | /* This is called when Exim is running as a server, after having received | |
1947 | the STARTTLS command. It must respond to that command, and then negotiate | |
1948 | a TLS session. | |
1949 | ||
1950 | Arguments: | |
1951 | require_ciphers allowed ciphers | |
cf0c6164 | 1952 | errstr pointer to error message |
059ec3d9 PH |
1953 | |
1954 | Returns: OK on success | |
1955 | DEFER for errors before the start of the negotiation | |
4c04137d | 1956 | FAIL for errors during the negotiation; the server can't |
059ec3d9 PH |
1957 | continue running. |
1958 | */ | |
1959 | ||
1960 | int | |
cf0c6164 | 1961 | tls_server_start(const uschar * require_ciphers, uschar ** errstr) |
059ec3d9 PH |
1962 | { |
1963 | int rc; | |
cf0c6164 JH |
1964 | uschar * expciphers; |
1965 | tls_ext_ctx_cb * cbinfo; | |
f69979cf | 1966 | static uschar peerdn[256]; |
817d9f57 | 1967 | static uschar cipherbuf[256]; |
059ec3d9 PH |
1968 | |
1969 | /* Check for previous activation */ | |
1970 | ||
817d9f57 | 1971 | if (tls_in.active >= 0) |
059ec3d9 | 1972 | { |
cf0c6164 | 1973 | tls_error(US"STARTTLS received after TLS started", NULL, US"", errstr); |
925ac8e4 | 1974 | smtp_printf("554 Already in TLS\r\n", FALSE); |
059ec3d9 PH |
1975 | return FAIL; |
1976 | } | |
1977 | ||
1978 | /* Initialize the SSL library. If it fails, it will already have logged | |
1979 | the error. */ | |
1980 | ||
817d9f57 | 1981 | rc = tls_init(&server_ctx, NULL, tls_dhparam, tls_certificate, tls_privatekey, |
f2de3a33 | 1982 | #ifndef DISABLE_OCSP |
47195144 | 1983 | tls_ocsp_file, /*XXX stack*/ |
3f7eeb86 | 1984 | #endif |
cf0c6164 | 1985 | NULL, &server_static_cbinfo, errstr); |
059ec3d9 | 1986 | if (rc != OK) return rc; |
817d9f57 | 1987 | cbinfo = server_static_cbinfo; |
059ec3d9 | 1988 | |
cf0c6164 | 1989 | if (!expand_check(require_ciphers, US"tls_require_ciphers", &expciphers, errstr)) |
059ec3d9 PH |
1990 | return FAIL; |
1991 | ||
1992 | /* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they | |
17c76198 PP |
1993 | were historically separated by underscores. So that I can use either form in my |
1994 | tests, and also for general convenience, we turn underscores into hyphens here. | |
1995 | */ | |
059ec3d9 | 1996 | |
c3033f13 | 1997 | if (expciphers) |
059ec3d9 | 1998 | { |
c3033f13 | 1999 | uschar * s = expciphers; |
059ec3d9 PH |
2000 | while (*s != 0) { if (*s == '_') *s = '-'; s++; } |
2001 | DEBUG(D_tls) debug_printf("required ciphers: %s\n", expciphers); | |
817d9f57 | 2002 | if (!SSL_CTX_set_cipher_list(server_ctx, CS expciphers)) |
cf0c6164 | 2003 | return tls_error(US"SSL_CTX_set_cipher_list", NULL, NULL, errstr); |
7be682ca | 2004 | cbinfo->server_cipher_list = expciphers; |
059ec3d9 PH |
2005 | } |
2006 | ||
2007 | /* If this is a host for which certificate verification is mandatory or | |
2008 | optional, set up appropriately. */ | |
2009 | ||
817d9f57 | 2010 | tls_in.certificate_verified = FALSE; |
c0635b6d | 2011 | #ifdef SUPPORT_DANE |
53a7196b JH |
2012 | tls_in.dane_verified = FALSE; |
2013 | #endif | |
a2ff477a | 2014 | server_verify_callback_called = FALSE; |
059ec3d9 PH |
2015 | |
2016 | if (verify_check_host(&tls_verify_hosts) == OK) | |
2017 | { | |
983207c1 | 2018 | rc = setup_certs(server_ctx, tls_verify_certificates, tls_crl, NULL, |
cf0c6164 | 2019 | FALSE, verify_callback_server, errstr); |
059ec3d9 | 2020 | if (rc != OK) return rc; |
a2ff477a | 2021 | server_verify_optional = FALSE; |
059ec3d9 PH |
2022 | } |
2023 | else if (verify_check_host(&tls_try_verify_hosts) == OK) | |
2024 | { | |
983207c1 | 2025 | rc = setup_certs(server_ctx, tls_verify_certificates, tls_crl, NULL, |
cf0c6164 | 2026 | TRUE, verify_callback_server, errstr); |
059ec3d9 | 2027 | if (rc != OK) return rc; |
a2ff477a | 2028 | server_verify_optional = TRUE; |
059ec3d9 PH |
2029 | } |
2030 | ||
2031 | /* Prepare for new connection */ | |
2032 | ||
cf0c6164 JH |
2033 | if (!(server_ssl = SSL_new(server_ctx))) |
2034 | return tls_error(US"SSL_new", NULL, NULL, errstr); | |
da3ad30d PP |
2035 | |
2036 | /* Warning: we used to SSL_clear(ssl) here, it was removed. | |
2037 | * | |
2038 | * With the SSL_clear(), we get strange interoperability bugs with | |
2039 | * OpenSSL 1.0.1b and TLS1.1/1.2. It looks as though this may be a bug in | |
2040 | * OpenSSL itself, as a clear should not lead to inability to follow protocols. | |
2041 | * | |
2042 | * The SSL_clear() call is to let an existing SSL* be reused, typically after | |
2043 | * session shutdown. In this case, we have a brand new object and there's no | |
2044 | * obvious reason to immediately clear it. I'm guessing that this was | |
2045 | * originally added because of incomplete initialisation which the clear fixed, | |
2046 | * in some historic release. | |
2047 | */ | |
059ec3d9 PH |
2048 | |
2049 | /* Set context and tell client to go ahead, except in the case of TLS startup | |
2050 | on connection, where outputting anything now upsets the clients and tends to | |
2051 | make them disconnect. We need to have an explicit fflush() here, to force out | |
2052 | the response. Other smtp_printf() calls do not need it, because in non-TLS | |
2053 | mode, the fflush() happens when smtp_getc() is called. */ | |
2054 | ||
817d9f57 JH |
2055 | SSL_set_session_id_context(server_ssl, sid_ctx, Ustrlen(sid_ctx)); |
2056 | if (!tls_in.on_connect) | |
059ec3d9 | 2057 | { |
925ac8e4 | 2058 | smtp_printf("220 TLS go ahead\r\n", FALSE); |
059ec3d9 PH |
2059 | fflush(smtp_out); |
2060 | } | |
2061 | ||
2062 | /* Now negotiate the TLS session. We put our own timer on it, since it seems | |
2063 | that the OpenSSL library doesn't. */ | |
2064 | ||
817d9f57 JH |
2065 | SSL_set_wfd(server_ssl, fileno(smtp_out)); |
2066 | SSL_set_rfd(server_ssl, fileno(smtp_in)); | |
2067 | SSL_set_accept_state(server_ssl); | |
059ec3d9 PH |
2068 | |
2069 | DEBUG(D_tls) debug_printf("Calling SSL_accept\n"); | |
2070 | ||
2071 | sigalrm_seen = FALSE; | |
2072 | if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout); | |
817d9f57 | 2073 | rc = SSL_accept(server_ssl); |
059ec3d9 PH |
2074 | alarm(0); |
2075 | ||
2076 | if (rc <= 0) | |
2077 | { | |
cf0c6164 | 2078 | (void) tls_error(US"SSL_accept", NULL, sigalrm_seen ? US"timed out" : NULL, errstr); |
059ec3d9 PH |
2079 | return FAIL; |
2080 | } | |
2081 | ||
2082 | DEBUG(D_tls) debug_printf("SSL_accept was successful\n"); | |
2083 | ||
2084 | /* TLS has been set up. Adjust the input functions to read via TLS, | |
2085 | and initialize things. */ | |
2086 | ||
f69979cf JH |
2087 | peer_cert(server_ssl, &tls_in, peerdn, sizeof(peerdn)); |
2088 | ||
817d9f57 JH |
2089 | construct_cipher_name(server_ssl, cipherbuf, sizeof(cipherbuf), &tls_in.bits); |
2090 | tls_in.cipher = cipherbuf; | |
059ec3d9 PH |
2091 | |
2092 | DEBUG(D_tls) | |
2093 | { | |
2094 | uschar buf[2048]; | |
817d9f57 | 2095 | if (SSL_get_shared_ciphers(server_ssl, CS buf, sizeof(buf)) != NULL) |
059ec3d9 PH |
2096 | debug_printf("Shared ciphers: %s\n", buf); |
2097 | } | |
2098 | ||
9d1c15ef JH |
2099 | /* Record the certificate we presented */ |
2100 | { | |
2101 | X509 * crt = SSL_get_certificate(server_ssl); | |
2102 | tls_in.ourcert = crt ? X509_dup(crt) : NULL; | |
2103 | } | |
059ec3d9 | 2104 | |
817d9f57 JH |
2105 | /* Only used by the server-side tls (tls_in), including tls_getc. |
2106 | Client-side (tls_out) reads (seem to?) go via | |
2107 | smtp_read_response()/ip_recv(). | |
2108 | Hence no need to duplicate for _in and _out. | |
2109 | */ | |
b808677c | 2110 | if (!ssl_xfer_buffer) ssl_xfer_buffer = store_malloc(ssl_xfer_buffer_size); |
059ec3d9 | 2111 | ssl_xfer_buffer_lwm = ssl_xfer_buffer_hwm = 0; |
8b77d27a | 2112 | ssl_xfer_eof = ssl_xfer_error = FALSE; |
059ec3d9 PH |
2113 | |
2114 | receive_getc = tls_getc; | |
0d81dabc | 2115 | receive_getbuf = tls_getbuf; |
584e96c6 | 2116 | receive_get_cache = tls_get_cache; |
059ec3d9 PH |
2117 | receive_ungetc = tls_ungetc; |
2118 | receive_feof = tls_feof; | |
2119 | receive_ferror = tls_ferror; | |
58eb016e | 2120 | receive_smtp_buffered = tls_smtp_buffered; |
059ec3d9 | 2121 | |
817d9f57 | 2122 | tls_in.active = fileno(smtp_out); |
059ec3d9 PH |
2123 | return OK; |
2124 | } | |
2125 | ||
2126 | ||
2127 | ||
2128 | ||
043b1248 JH |
2129 | static int |
2130 | tls_client_basic_ctx_init(SSL_CTX * ctx, | |
cf0c6164 JH |
2131 | host_item * host, smtp_transport_options_block * ob, tls_ext_ctx_cb * cbinfo, |
2132 | uschar ** errstr) | |
043b1248 JH |
2133 | { |
2134 | int rc; | |
94431adb | 2135 | /* stick to the old behaviour for compatibility if tls_verify_certificates is |
043b1248 JH |
2136 | set but both tls_verify_hosts and tls_try_verify_hosts is not set. Check only |
2137 | the specified host patterns if one of them is defined */ | |
2138 | ||
610ff438 JH |
2139 | if ( ( !ob->tls_verify_hosts |
2140 | && (!ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts) | |
2141 | ) | |
5130845b | 2142 | || (verify_check_given_host(&ob->tls_verify_hosts, host) == OK) |
aa2a70ba | 2143 | ) |
043b1248 | 2144 | client_verify_optional = FALSE; |
5130845b | 2145 | else if (verify_check_given_host(&ob->tls_try_verify_hosts, host) == OK) |
aa2a70ba JH |
2146 | client_verify_optional = TRUE; |
2147 | else | |
2148 | return OK; | |
2149 | ||
2150 | if ((rc = setup_certs(ctx, ob->tls_verify_certificates, | |
cf0c6164 JH |
2151 | ob->tls_crl, host, client_verify_optional, verify_callback_client, |
2152 | errstr)) != OK) | |
aa2a70ba | 2153 | return rc; |
043b1248 | 2154 | |
5130845b | 2155 | if (verify_check_given_host(&ob->tls_verify_cert_hostnames, host) == OK) |
043b1248 | 2156 | { |
4af0d74a | 2157 | cbinfo->verify_cert_hostnames = |
8c5d388a | 2158 | #ifdef SUPPORT_I18N |
4af0d74a JH |
2159 | string_domain_utf8_to_alabel(host->name, NULL); |
2160 | #else | |
2161 | host->name; | |
2162 | #endif | |
aa2a70ba JH |
2163 | DEBUG(D_tls) debug_printf("Cert hostname to check: \"%s\"\n", |
2164 | cbinfo->verify_cert_hostnames); | |
043b1248 | 2165 | } |
043b1248 JH |
2166 | return OK; |
2167 | } | |
059ec3d9 | 2168 | |
fde080a4 | 2169 | |
c0635b6d | 2170 | #ifdef SUPPORT_DANE |
fde080a4 | 2171 | static int |
cf0c6164 | 2172 | dane_tlsa_load(SSL * ssl, host_item * host, dns_answer * dnsa, uschar ** errstr) |
fde080a4 JH |
2173 | { |
2174 | dns_record * rr; | |
2175 | dns_scan dnss; | |
2176 | const char * hostnames[2] = { CS host->name, NULL }; | |
2177 | int found = 0; | |
2178 | ||
2179 | if (DANESSL_init(ssl, NULL, hostnames) != 1) | |
cf0c6164 | 2180 | return tls_error(US"hostnames load", host, NULL, errstr); |
fde080a4 JH |
2181 | |
2182 | for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); | |
2183 | rr; | |
2184 | rr = dns_next_rr(dnsa, &dnss, RESET_NEXT) | |
2185 | ) if (rr->type == T_TLSA) | |
2186 | { | |
c3033f13 | 2187 | const uschar * p = rr->data; |
fde080a4 JH |
2188 | uint8_t usage, selector, mtype; |
2189 | const char * mdname; | |
2190 | ||
fde080a4 | 2191 | usage = *p++; |
133d2546 JH |
2192 | |
2193 | /* Only DANE-TA(2) and DANE-EE(3) are supported */ | |
2194 | if (usage != 2 && usage != 3) continue; | |
2195 | ||
fde080a4 JH |
2196 | selector = *p++; |
2197 | mtype = *p++; | |
2198 | ||
2199 | switch (mtype) | |
2200 | { | |
133d2546 JH |
2201 | default: continue; /* Only match-types 0, 1, 2 are supported */ |
2202 | case 0: mdname = NULL; break; | |
2203 | case 1: mdname = "sha256"; break; | |
2204 | case 2: mdname = "sha512"; break; | |
fde080a4 JH |
2205 | } |
2206 | ||
133d2546 | 2207 | found++; |
fde080a4 JH |
2208 | switch (DANESSL_add_tlsa(ssl, usage, selector, mdname, p, rr->size - 3)) |
2209 | { | |
2210 | default: | |
cf0c6164 | 2211 | return tls_error(US"tlsa load", host, NULL, errstr); |
c035b645 | 2212 | case 0: /* action not taken */ |
fde080a4 JH |
2213 | case 1: break; |
2214 | } | |
594706ea JH |
2215 | |
2216 | tls_out.tlsa_usage |= 1<<usage; | |
fde080a4 JH |
2217 | } |
2218 | ||
2219 | if (found) | |
2220 | return OK; | |
2221 | ||
133d2546 | 2222 | log_write(0, LOG_MAIN, "DANE error: No usable TLSA records"); |
6ebd79ec | 2223 | return DEFER; |
fde080a4 | 2224 | } |
c0635b6d | 2225 | #endif /*SUPPORT_DANE*/ |
fde080a4 JH |
2226 | |
2227 | ||
2228 | ||
059ec3d9 PH |
2229 | /************************************************* |
2230 | * Start a TLS session in a client * | |
2231 | *************************************************/ | |
2232 | ||
2233 | /* Called from the smtp transport after STARTTLS has been accepted. | |
2234 | ||
2235 | Argument: | |
2236 | fd the fd of the connection | |
2237 | host connected host (for messages) | |
83da1223 | 2238 | addr the first address |
a7538db1 | 2239 | tb transport (always smtp) |
0e66b3b6 | 2240 | tlsa_dnsa tlsa lookup, if DANE, else null |
cf0c6164 | 2241 | errstr error string pointer |
059ec3d9 PH |
2242 | |
2243 | Returns: OK on success | |
2244 | FAIL otherwise - note that tls_error() will not give DEFER | |
2245 | because this is not a server | |
2246 | */ | |
2247 | ||
2248 | int | |
f5d78688 | 2249 | tls_client_start(int fd, host_item *host, address_item *addr, |
cf0c6164 | 2250 | transport_instance * tb, |
c0635b6d | 2251 | #ifdef SUPPORT_DANE |
cf0c6164 | 2252 | dns_answer * tlsa_dnsa, |
0e66b3b6 | 2253 | #endif |
cf0c6164 | 2254 | uschar ** errstr) |
059ec3d9 | 2255 | { |
a7538db1 JH |
2256 | smtp_transport_options_block * ob = |
2257 | (smtp_transport_options_block *)tb->options_block; | |
f69979cf | 2258 | static uschar peerdn[256]; |
868f5672 | 2259 | uschar * expciphers; |
059ec3d9 | 2260 | int rc; |
817d9f57 | 2261 | static uschar cipherbuf[256]; |
043b1248 JH |
2262 | |
2263 | #ifndef DISABLE_OCSP | |
043b1248 | 2264 | BOOL request_ocsp = FALSE; |
6634ac8d | 2265 | BOOL require_ocsp = FALSE; |
043b1248 | 2266 | #endif |
043b1248 | 2267 | |
c0635b6d | 2268 | #ifdef SUPPORT_DANE |
594706ea | 2269 | tls_out.tlsa_usage = 0; |
043b1248 JH |
2270 | #endif |
2271 | ||
f2de3a33 | 2272 | #ifndef DISABLE_OCSP |
043b1248 | 2273 | { |
c0635b6d | 2274 | # ifdef SUPPORT_DANE |
4f59c424 JH |
2275 | if ( tlsa_dnsa |
2276 | && ob->hosts_request_ocsp[0] == '*' | |
2277 | && ob->hosts_request_ocsp[1] == '\0' | |
2278 | ) | |
2279 | { | |
2280 | /* Unchanged from default. Use a safer one under DANE */ | |
2281 | request_ocsp = TRUE; | |
2282 | ob->hosts_request_ocsp = US"${if or { {= {0}{$tls_out_tlsa_usage}} " | |
2283 | " {= {4}{$tls_out_tlsa_usage}} } " | |
2284 | " {*}{}}"; | |
2285 | } | |
2286 | # endif | |
2287 | ||
5130845b JH |
2288 | if ((require_ocsp = |
2289 | verify_check_given_host(&ob->hosts_require_ocsp, host) == OK)) | |
fca41d5a JH |
2290 | request_ocsp = TRUE; |
2291 | else | |
c0635b6d | 2292 | # ifdef SUPPORT_DANE |
4f59c424 | 2293 | if (!request_ocsp) |
fca41d5a | 2294 | # endif |
5130845b JH |
2295 | request_ocsp = |
2296 | verify_check_given_host(&ob->hosts_request_ocsp, host) == OK; | |
043b1248 | 2297 | } |
f5d78688 | 2298 | #endif |
059ec3d9 | 2299 | |
65867078 JH |
2300 | rc = tls_init(&client_ctx, host, NULL, |
2301 | ob->tls_certificate, ob->tls_privatekey, | |
f2de3a33 | 2302 | #ifndef DISABLE_OCSP |
44662487 | 2303 | (void *)(long)request_ocsp, |
3f7eeb86 | 2304 | #endif |
cf0c6164 | 2305 | addr, &client_static_cbinfo, errstr); |
059ec3d9 PH |
2306 | if (rc != OK) return rc; |
2307 | ||
817d9f57 | 2308 | tls_out.certificate_verified = FALSE; |
a2ff477a | 2309 | client_verify_callback_called = FALSE; |
059ec3d9 | 2310 | |
5ec37a55 PP |
2311 | expciphers = NULL; |
2312 | #ifdef SUPPORT_DANE | |
2313 | if (tlsa_dnsa) | |
2314 | { | |
2315 | /* We fall back to tls_require_ciphers if unset, empty or forced failure, but | |
2316 | other failures should be treated as problems. */ | |
2317 | if (ob->dane_require_tls_ciphers && | |
2318 | !expand_check(ob->dane_require_tls_ciphers, US"dane_require_tls_ciphers", | |
2319 | &expciphers, errstr)) | |
2320 | return FAIL; | |
2321 | if (expciphers && *expciphers == '\0') | |
2322 | expciphers = NULL; | |
2323 | } | |
2324 | #endif | |
2325 | if (!expciphers && | |
2326 | !expand_check(ob->tls_require_ciphers, US"tls_require_ciphers", | |
2327 | &expciphers, errstr)) | |
059ec3d9 PH |
2328 | return FAIL; |
2329 | ||
2330 | /* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they | |
2331 | are separated by underscores. So that I can use either form in my tests, and | |
2332 | also for general convenience, we turn underscores into hyphens here. */ | |
2333 | ||
cf0c6164 | 2334 | if (expciphers) |
059ec3d9 PH |
2335 | { |
2336 | uschar *s = expciphers; | |
cf0c6164 | 2337 | while (*s) { if (*s == '_') *s = '-'; s++; } |
059ec3d9 | 2338 | DEBUG(D_tls) debug_printf("required ciphers: %s\n", expciphers); |
817d9f57 | 2339 | if (!SSL_CTX_set_cipher_list(client_ctx, CS expciphers)) |
cf0c6164 | 2340 | return tls_error(US"SSL_CTX_set_cipher_list", host, NULL, errstr); |
059ec3d9 PH |
2341 | } |
2342 | ||
c0635b6d | 2343 | #ifdef SUPPORT_DANE |
0e66b3b6 | 2344 | if (tlsa_dnsa) |
a63be306 | 2345 | { |
02af313d JH |
2346 | SSL_CTX_set_verify(client_ctx, |
2347 | SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT, | |
2348 | verify_callback_client_dane); | |
e5cccda9 | 2349 | |
043b1248 | 2350 | if (!DANESSL_library_init()) |
cf0c6164 | 2351 | return tls_error(US"library init", host, NULL, errstr); |
043b1248 | 2352 | if (DANESSL_CTX_init(client_ctx) <= 0) |
cf0c6164 | 2353 | return tls_error(US"context init", host, NULL, errstr); |
043b1248 JH |
2354 | } |
2355 | else | |
e51c7be2 | 2356 | |
043b1248 JH |
2357 | #endif |
2358 | ||
cf0c6164 JH |
2359 | if ((rc = tls_client_basic_ctx_init(client_ctx, host, ob, |
2360 | client_static_cbinfo, errstr)) != OK) | |
65867078 | 2361 | return rc; |
059ec3d9 | 2362 | |
65867078 | 2363 | if ((client_ssl = SSL_new(client_ctx)) == NULL) |
cf0c6164 | 2364 | return tls_error(US"SSL_new", host, NULL, errstr); |
817d9f57 JH |
2365 | SSL_set_session_id_context(client_ssl, sid_ctx, Ustrlen(sid_ctx)); |
2366 | SSL_set_fd(client_ssl, fd); | |
2367 | SSL_set_connect_state(client_ssl); | |
059ec3d9 | 2368 | |
65867078 | 2369 | if (ob->tls_sni) |
3f0945ff | 2370 | { |
cf0c6164 | 2371 | if (!expand_check(ob->tls_sni, US"tls_sni", &tls_out.sni, errstr)) |
3f0945ff | 2372 | return FAIL; |
cf0c6164 | 2373 | if (!tls_out.sni) |
2c9a0e86 PP |
2374 | { |
2375 | DEBUG(D_tls) debug_printf("Setting TLS SNI forced to fail, not sending\n"); | |
2376 | } | |
ec4b68e5 | 2377 | else if (!Ustrlen(tls_out.sni)) |
817d9f57 | 2378 | tls_out.sni = NULL; |
3f0945ff PP |
2379 | else |
2380 | { | |
35731706 | 2381 | #ifdef EXIM_HAVE_OPENSSL_TLSEXT |
817d9f57 JH |
2382 | DEBUG(D_tls) debug_printf("Setting TLS SNI \"%s\"\n", tls_out.sni); |
2383 | SSL_set_tlsext_host_name(client_ssl, tls_out.sni); | |
35731706 | 2384 | #else |
66802652 | 2385 | log_write(0, LOG_MAIN, "SNI unusable with this OpenSSL library version; ignoring \"%s\"\n", |
02d9264f | 2386 | tls_out.sni); |
35731706 | 2387 | #endif |
3f0945ff PP |
2388 | } |
2389 | } | |
2390 | ||
c0635b6d | 2391 | #ifdef SUPPORT_DANE |
0e66b3b6 | 2392 | if (tlsa_dnsa) |
cf0c6164 | 2393 | if ((rc = dane_tlsa_load(client_ssl, host, tlsa_dnsa, errstr)) != OK) |
594706ea JH |
2394 | return rc; |
2395 | #endif | |
2396 | ||
f2de3a33 | 2397 | #ifndef DISABLE_OCSP |
f5d78688 JH |
2398 | /* Request certificate status at connection-time. If the server |
2399 | does OCSP stapling we will get the callback (set in tls_init()) */ | |
c0635b6d | 2400 | # ifdef SUPPORT_DANE |
594706ea JH |
2401 | if (request_ocsp) |
2402 | { | |
2403 | const uschar * s; | |
41afb5cb JH |
2404 | if ( ((s = ob->hosts_require_ocsp) && Ustrstr(s, US"tls_out_tlsa_usage")) |
2405 | || ((s = ob->hosts_request_ocsp) && Ustrstr(s, US"tls_out_tlsa_usage")) | |
594706ea JH |
2406 | ) |
2407 | { /* Re-eval now $tls_out_tlsa_usage is populated. If | |
2408 | this means we avoid the OCSP request, we wasted the setup | |
2409 | cost in tls_init(). */ | |
5130845b JH |
2410 | require_ocsp = verify_check_given_host(&ob->hosts_require_ocsp, host) == OK; |
2411 | request_ocsp = require_ocsp | |
2412 | || verify_check_given_host(&ob->hosts_request_ocsp, host) == OK; | |
594706ea JH |
2413 | } |
2414 | } | |
b50c8b84 JH |
2415 | # endif |
2416 | ||
44662487 JH |
2417 | if (request_ocsp) |
2418 | { | |
f5d78688 | 2419 | SSL_set_tlsext_status_type(client_ssl, TLSEXT_STATUSTYPE_ocsp); |
44662487 JH |
2420 | client_static_cbinfo->u_ocsp.client.verify_required = require_ocsp; |
2421 | tls_out.ocsp = OCSP_NOT_RESP; | |
2422 | } | |
f5d78688 JH |
2423 | #endif |
2424 | ||
0cbf2b82 | 2425 | #ifndef DISABLE_EVENT |
774ef2d7 | 2426 | client_static_cbinfo->event_action = tb->event_action; |
a7538db1 | 2427 | #endif |
043b1248 | 2428 | |
059ec3d9 PH |
2429 | /* There doesn't seem to be a built-in timeout on connection. */ |
2430 | ||
2431 | DEBUG(D_tls) debug_printf("Calling SSL_connect\n"); | |
2432 | sigalrm_seen = FALSE; | |
65867078 | 2433 | alarm(ob->command_timeout); |
817d9f57 | 2434 | rc = SSL_connect(client_ssl); |
059ec3d9 PH |
2435 | alarm(0); |
2436 | ||
c0635b6d | 2437 | #ifdef SUPPORT_DANE |
0e66b3b6 | 2438 | if (tlsa_dnsa) |
fde080a4 | 2439 | DANESSL_cleanup(client_ssl); |
043b1248 JH |
2440 | #endif |
2441 | ||
059ec3d9 | 2442 | if (rc <= 0) |
cf0c6164 JH |
2443 | return tls_error(US"SSL_connect", host, sigalrm_seen ? US"timed out" : NULL, |
2444 | errstr); | |
059ec3d9 PH |
2445 | |
2446 | DEBUG(D_tls) debug_printf("SSL_connect succeeded\n"); | |
2447 | ||
f69979cf | 2448 | peer_cert(client_ssl, &tls_out, peerdn, sizeof(peerdn)); |
059ec3d9 | 2449 | |
817d9f57 JH |
2450 | construct_cipher_name(client_ssl, cipherbuf, sizeof(cipherbuf), &tls_out.bits); |
2451 | tls_out.cipher = cipherbuf; | |
059ec3d9 | 2452 | |
9d1c15ef JH |
2453 | /* Record the certificate we presented */ |
2454 | { | |
2455 | X509 * crt = SSL_get_certificate(client_ssl); | |
2456 | tls_out.ourcert = crt ? X509_dup(crt) : NULL; | |
2457 | } | |
2458 | ||
817d9f57 | 2459 | tls_out.active = fd; |
059ec3d9 PH |
2460 | return OK; |
2461 | } | |
2462 | ||
2463 | ||
2464 | ||
2465 | ||
2466 | ||
0d81dabc JH |
2467 | static BOOL |
2468 | tls_refill(unsigned lim) | |
2469 | { | |
2470 | int error; | |
2471 | int inbytes; | |
2472 | ||
2473 | DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", server_ssl, | |
2474 | ssl_xfer_buffer, ssl_xfer_buffer_size); | |
2475 | ||
2476 | if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout); | |
2477 | inbytes = SSL_read(server_ssl, CS ssl_xfer_buffer, | |
2478 | MIN(ssl_xfer_buffer_size, lim)); | |
2479 | error = SSL_get_error(server_ssl, inbytes); | |
9723f966 JH |
2480 | if (smtp_receive_timeout > 0) alarm(0); |
2481 | ||
2482 | if (had_command_timeout) /* set by signal handler */ | |
2483 | smtp_command_timeout_exit(); /* does not return */ | |
2484 | if (had_command_sigterm) | |
2485 | smtp_command_sigterm_exit(); | |
2486 | if (had_data_timeout) | |
2487 | smtp_data_timeout_exit(); | |
2488 | if (had_data_sigint) | |
2489 | smtp_data_sigint_exit(); | |
0d81dabc JH |
2490 | |
2491 | /* SSL_ERROR_ZERO_RETURN appears to mean that the SSL session has been | |
2492 | closed down, not that the socket itself has been closed down. Revert to | |
2493 | non-SSL handling. */ | |
2494 | ||
2495 | if (error == SSL_ERROR_ZERO_RETURN) | |
2496 | { | |
2497 | DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n"); | |
2498 | ||
2499 | receive_getc = smtp_getc; | |
2500 | receive_getbuf = smtp_getbuf; | |
2501 | receive_get_cache = smtp_get_cache; | |
2502 | receive_ungetc = smtp_ungetc; | |
2503 | receive_feof = smtp_feof; | |
2504 | receive_ferror = smtp_ferror; | |
2505 | receive_smtp_buffered = smtp_buffered; | |
2506 | ||
dec766a1 WB |
2507 | if (SSL_get_shutdown(server_ssl) == SSL_RECEIVED_SHUTDOWN) |
2508 | SSL_shutdown(server_ssl); | |
2509 | ||
37f0ce65 | 2510 | #ifndef DISABLE_OCSP |
dec766a1 | 2511 | sk_X509_pop_free(server_static_cbinfo->verify_stack, X509_free); |
37f0ce65 JH |
2512 | server_static_cbinfo->verify_stack = NULL; |
2513 | #endif | |
0d81dabc | 2514 | SSL_free(server_ssl); |
dec766a1 | 2515 | SSL_CTX_free(server_ctx); |
dec766a1 | 2516 | server_ctx = NULL; |
0d81dabc JH |
2517 | server_ssl = NULL; |
2518 | tls_in.active = -1; | |
2519 | tls_in.bits = 0; | |
2520 | tls_in.cipher = NULL; | |
2521 | tls_in.peerdn = NULL; | |
2522 | tls_in.sni = NULL; | |
2523 | ||
2524 | return FALSE; | |
2525 | } | |
2526 | ||
2527 | /* Handle genuine errors */ | |
2528 | ||
2529 | else if (error == SSL_ERROR_SSL) | |
2530 | { | |
2531 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
2532 | log_write(0, LOG_MAIN, "TLS error (SSL_read): %s", ssl_errstring); | |
8b77d27a | 2533 | ssl_xfer_error = TRUE; |
0d81dabc JH |
2534 | return FALSE; |
2535 | } | |
2536 | ||
2537 | else if (error != SSL_ERROR_NONE) | |
2538 | { | |
2539 | DEBUG(D_tls) debug_printf("Got SSL error %d\n", error); | |
8b77d27a | 2540 | ssl_xfer_error = TRUE; |
0d81dabc JH |
2541 | return FALSE; |
2542 | } | |
2543 | ||
2544 | #ifndef DISABLE_DKIM | |
2545 | dkim_exim_verify_feed(ssl_xfer_buffer, inbytes); | |
2546 | #endif | |
2547 | ssl_xfer_buffer_hwm = inbytes; | |
2548 | ssl_xfer_buffer_lwm = 0; | |
2549 | return TRUE; | |
2550 | } | |
2551 | ||
2552 | ||
059ec3d9 PH |
2553 | /************************************************* |
2554 | * TLS version of getc * | |
2555 | *************************************************/ | |
2556 | ||
2557 | /* This gets the next byte from the TLS input buffer. If the buffer is empty, | |
2558 | it refills the buffer via the SSL reading function. | |
2559 | ||
bd8fbe36 | 2560 | Arguments: lim Maximum amount to read/buffer |
059ec3d9 | 2561 | Returns: the next character or EOF |
817d9f57 JH |
2562 | |
2563 | Only used by the server-side TLS. | |
059ec3d9 PH |
2564 | */ |
2565 | ||
2566 | int | |
bd8fbe36 | 2567 | tls_getc(unsigned lim) |
059ec3d9 PH |
2568 | { |
2569 | if (ssl_xfer_buffer_lwm >= ssl_xfer_buffer_hwm) | |
0d81dabc JH |
2570 | if (!tls_refill(lim)) |
2571 | return ssl_xfer_error ? EOF : smtp_getc(lim); | |
059ec3d9 | 2572 | |
0d81dabc | 2573 | /* Something in the buffer; return next uschar */ |
059ec3d9 | 2574 | |
0d81dabc JH |
2575 | return ssl_xfer_buffer[ssl_xfer_buffer_lwm++]; |
2576 | } | |
059ec3d9 | 2577 | |
0d81dabc JH |
2578 | uschar * |
2579 | tls_getbuf(unsigned * len) | |
2580 | { | |
2581 | unsigned size; | |
2582 | uschar * buf; | |
ba084640 | 2583 | |
0d81dabc JH |
2584 | if (ssl_xfer_buffer_lwm >= ssl_xfer_buffer_hwm) |
2585 | if (!tls_refill(*len)) | |
059ec3d9 | 2586 | { |
0d81dabc JH |
2587 | if (!ssl_xfer_error) return smtp_getbuf(len); |
2588 | *len = 0; | |
2589 | return NULL; | |
059ec3d9 | 2590 | } |
c80c5570 | 2591 | |
0d81dabc JH |
2592 | if ((size = ssl_xfer_buffer_hwm - ssl_xfer_buffer_lwm) > *len) |
2593 | size = *len; | |
2594 | buf = &ssl_xfer_buffer[ssl_xfer_buffer_lwm]; | |
2595 | ssl_xfer_buffer_lwm += size; | |
2596 | *len = size; | |
2597 | return buf; | |
059ec3d9 PH |
2598 | } |
2599 | ||
0d81dabc | 2600 | |
584e96c6 JH |
2601 | void |
2602 | tls_get_cache() | |
2603 | { | |
9960d1e5 | 2604 | #ifndef DISABLE_DKIM |
584e96c6 JH |
2605 | int n = ssl_xfer_buffer_hwm - ssl_xfer_buffer_lwm; |
2606 | if (n > 0) | |
2607 | dkim_exim_verify_feed(ssl_xfer_buffer+ssl_xfer_buffer_lwm, n); | |
584e96c6 | 2608 | #endif |
9960d1e5 | 2609 | } |
584e96c6 | 2610 | |
059ec3d9 | 2611 | |
925ac8e4 JH |
2612 | BOOL |
2613 | tls_could_read(void) | |
2614 | { | |
a5ffa9b4 | 2615 | return ssl_xfer_buffer_lwm < ssl_xfer_buffer_hwm || SSL_pending(server_ssl) > 0; |
925ac8e4 JH |
2616 | } |
2617 | ||
059ec3d9 PH |
2618 | |
2619 | /************************************************* | |
2620 | * Read bytes from TLS channel * | |
2621 | *************************************************/ | |
2622 | ||
2623 | /* | |
2624 | Arguments: | |
2625 | buff buffer of data | |
2626 | len size of buffer | |
2627 | ||
2628 | Returns: the number of bytes read | |
2629 | -1 after a failed read | |
817d9f57 JH |
2630 | |
2631 | Only used by the client-side TLS. | |
059ec3d9 PH |
2632 | */ |
2633 | ||
2634 | int | |
389ca47a | 2635 | tls_read(BOOL is_server, uschar *buff, size_t len) |
059ec3d9 | 2636 | { |
389ca47a | 2637 | SSL *ssl = is_server ? server_ssl : client_ssl; |
059ec3d9 PH |
2638 | int inbytes; |
2639 | int error; | |
2640 | ||
389ca47a | 2641 | DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", ssl, |
c80c5570 | 2642 | buff, (unsigned int)len); |
059ec3d9 | 2643 | |
389ca47a JH |
2644 | inbytes = SSL_read(ssl, CS buff, len); |
2645 | error = SSL_get_error(ssl, inbytes); | |
059ec3d9 PH |
2646 | |
2647 | if (error == SSL_ERROR_ZERO_RETURN) | |
2648 | { | |
2649 | DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n"); | |
2650 | return -1; | |
2651 | } | |
2652 | else if (error != SSL_ERROR_NONE) | |
059ec3d9 | 2653 | return -1; |
059ec3d9 PH |
2654 | |
2655 | return inbytes; | |
2656 | } | |
2657 | ||
2658 | ||
2659 | ||
2660 | ||
2661 | ||
2662 | /************************************************* | |
2663 | * Write bytes down TLS channel * | |
2664 | *************************************************/ | |
2665 | ||
2666 | /* | |
2667 | Arguments: | |
817d9f57 | 2668 | is_server channel specifier |
059ec3d9 PH |
2669 | buff buffer of data |
2670 | len number of bytes | |
925ac8e4 | 2671 | more further data expected soon |
059ec3d9 PH |
2672 | |
2673 | Returns: the number of bytes after a successful write, | |
2674 | -1 after a failed write | |
817d9f57 JH |
2675 | |
2676 | Used by both server-side and client-side TLS. | |
059ec3d9 PH |
2677 | */ |
2678 | ||
2679 | int | |
925ac8e4 | 2680 | tls_write(BOOL is_server, const uschar *buff, size_t len, BOOL more) |
059ec3d9 | 2681 | { |
a5ffa9b4 | 2682 | int outbytes, error, left; |
817d9f57 | 2683 | SSL *ssl = is_server ? server_ssl : client_ssl; |
acec9514 | 2684 | static gstring * corked = NULL; |
a5ffa9b4 | 2685 | |
ef698bf6 | 2686 | DEBUG(D_tls) debug_printf("%s(%p, %lu%s)\n", __FUNCTION__, |
b93be52e | 2687 | buff, (unsigned long)len, more ? ", more" : ""); |
a5ffa9b4 JH |
2688 | |
2689 | /* Lacking a CORK or MSG_MORE facility (such as GnuTLS has) we copy data when | |
2690 | "more" is notified. This hack is only ok if small amounts are involved AND only | |
2691 | one stream does it, in one context (i.e. no store reset). Currently it is used | |
2692 | for the responses to the received SMTP MAIL , RCPT, DATA sequence, only. */ | |
2693 | ||
2694 | if (is_server && (more || corked)) | |
2695 | { | |
acec9514 | 2696 | corked = string_catn(corked, buff, len); |
a5ffa9b4 JH |
2697 | if (more) |
2698 | return len; | |
acec9514 JH |
2699 | buff = CUS corked->s; |
2700 | len = corked->ptr; | |
2701 | corked = NULL; | |
a5ffa9b4 | 2702 | } |
059ec3d9 | 2703 | |
a5ffa9b4 | 2704 | for (left = len; left > 0;) |
059ec3d9 | 2705 | { |
c80c5570 | 2706 | DEBUG(D_tls) debug_printf("SSL_write(SSL, %p, %d)\n", buff, left); |
059ec3d9 PH |
2707 | outbytes = SSL_write(ssl, CS buff, left); |
2708 | error = SSL_get_error(ssl, outbytes); | |
2709 | DEBUG(D_tls) debug_printf("outbytes=%d error=%d\n", outbytes, error); | |
2710 | switch (error) | |
2711 | { | |
2712 | case SSL_ERROR_SSL: | |
96f5fe4c JH |
2713 | ERR_error_string(ERR_get_error(), ssl_errstring); |
2714 | log_write(0, LOG_MAIN, "TLS error (SSL_write): %s", ssl_errstring); | |
2715 | return -1; | |
059ec3d9 PH |
2716 | |
2717 | case SSL_ERROR_NONE: | |
96f5fe4c JH |
2718 | left -= outbytes; |
2719 | buff += outbytes; | |
2720 | break; | |
059ec3d9 PH |
2721 | |
2722 | case SSL_ERROR_ZERO_RETURN: | |
96f5fe4c JH |
2723 | log_write(0, LOG_MAIN, "SSL channel closed on write"); |
2724 | return -1; | |
059ec3d9 | 2725 | |
817d9f57 | 2726 | case SSL_ERROR_SYSCALL: |
96f5fe4c JH |
2727 | log_write(0, LOG_MAIN, "SSL_write: (from %s) syscall: %s", |
2728 | sender_fullhost ? sender_fullhost : US"<unknown>", | |
2729 | strerror(errno)); | |
2730 | return -1; | |
817d9f57 | 2731 | |
059ec3d9 | 2732 | default: |
96f5fe4c JH |
2733 | log_write(0, LOG_MAIN, "SSL_write error %d", error); |
2734 | return -1; | |
059ec3d9 PH |
2735 | } |
2736 | } | |
2737 | return len; | |
2738 | } | |
2739 | ||
2740 | ||
2741 | ||
2742 | /************************************************* | |
2743 | * Close down a TLS session * | |
2744 | *************************************************/ | |
2745 | ||
2746 | /* This is also called from within a delivery subprocess forked from the | |
2747 | daemon, to shut down the TLS library, without actually doing a shutdown (which | |
2748 | would tamper with the SSL session in the parent process). | |
2749 | ||
dec766a1 WB |
2750 | Arguments: |
2751 | shutdown 1 if TLS close-alert is to be sent, | |
2752 | 2 if also response to be waited for | |
2753 | ||
059ec3d9 | 2754 | Returns: nothing |
817d9f57 JH |
2755 | |
2756 | Used by both server-side and client-side TLS. | |
059ec3d9 PH |
2757 | */ |
2758 | ||
2759 | void | |
dec766a1 | 2760 | tls_close(BOOL is_server, int shutdown) |
059ec3d9 | 2761 | { |
dec766a1 | 2762 | SSL_CTX **ctxp = is_server ? &server_ctx : &client_ctx; |
817d9f57 | 2763 | SSL **sslp = is_server ? &server_ssl : &client_ssl; |
389ca47a | 2764 | int *fdp = is_server ? &tls_in.active : &tls_out.active; |
817d9f57 JH |
2765 | |
2766 | if (*fdp < 0) return; /* TLS was not active */ | |
059ec3d9 PH |
2767 | |
2768 | if (shutdown) | |
2769 | { | |
dec766a1 WB |
2770 | int rc; |
2771 | DEBUG(D_tls) debug_printf("tls_close(): shutting down TLS%s\n", | |
2772 | shutdown > 1 ? " (with response-wait)" : ""); | |
2773 | ||
2774 | if ( (rc = SSL_shutdown(*sslp)) == 0 /* send "close notify" alert */ | |
2775 | && shutdown > 1) | |
2776 | { | |
2777 | alarm(2); | |
2778 | rc = SSL_shutdown(*sslp); /* wait for response */ | |
2779 | alarm(0); | |
2780 | } | |
2781 | ||
2782 | if (rc < 0) DEBUG(D_tls) | |
2783 | { | |
2784 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
2785 | debug_printf("SSL_shutdown: %s\n", ssl_errstring); | |
2786 | } | |
2787 | } | |
2788 | ||
37f0ce65 | 2789 | #ifndef DISABLE_OCSP |
dec766a1 WB |
2790 | if (is_server) |
2791 | { | |
2792 | sk_X509_pop_free(server_static_cbinfo->verify_stack, X509_free); | |
dec766a1 | 2793 | server_static_cbinfo->verify_stack = NULL; |
059ec3d9 | 2794 | } |
37f0ce65 | 2795 | #endif |
059ec3d9 | 2796 | |
dec766a1 | 2797 | SSL_CTX_free(*ctxp); |
817d9f57 | 2798 | SSL_free(*sslp); |
dec766a1 | 2799 | *ctxp = NULL; |
817d9f57 | 2800 | *sslp = NULL; |
817d9f57 | 2801 | *fdp = -1; |
059ec3d9 PH |
2802 | } |
2803 | ||
36f12725 NM |
2804 | |
2805 | ||
2806 | ||
3375e053 PP |
2807 | /************************************************* |
2808 | * Let tls_require_ciphers be checked at startup * | |
2809 | *************************************************/ | |
2810 | ||
2811 | /* The tls_require_ciphers option, if set, must be something which the | |
2812 | library can parse. | |
2813 | ||
2814 | Returns: NULL on success, or error message | |
2815 | */ | |
2816 | ||
2817 | uschar * | |
2818 | tls_validate_require_cipher(void) | |
2819 | { | |
2820 | SSL_CTX *ctx; | |
2821 | uschar *s, *expciphers, *err; | |
2822 | ||
2823 | /* this duplicates from tls_init(), we need a better "init just global | |
2824 | state, for no specific purpose" singleton function of our own */ | |
2825 | ||
2826 | SSL_load_error_strings(); | |
2827 | OpenSSL_add_ssl_algorithms(); | |
2828 | #if (OPENSSL_VERSION_NUMBER >= 0x0090800fL) && !defined(OPENSSL_NO_SHA256) | |
2829 | /* SHA256 is becoming ever more popular. This makes sure it gets added to the | |
2830 | list of available digests. */ | |
2831 | EVP_add_digest(EVP_sha256()); | |
2832 | #endif | |
2833 | ||
2834 | if (!(tls_require_ciphers && *tls_require_ciphers)) | |
2835 | return NULL; | |
2836 | ||
cf0c6164 JH |
2837 | if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers, |
2838 | &err)) | |
3375e053 PP |
2839 | return US"failed to expand tls_require_ciphers"; |
2840 | ||
2841 | if (!(expciphers && *expciphers)) | |
2842 | return NULL; | |
2843 | ||
2844 | /* normalisation ripped from above */ | |
2845 | s = expciphers; | |
2846 | while (*s != 0) { if (*s == '_') *s = '-'; s++; } | |
2847 | ||
2848 | err = NULL; | |
2849 | ||
2850 | ctx = SSL_CTX_new(SSLv23_server_method()); | |
2851 | if (!ctx) | |
2852 | { | |
2853 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
2854 | return string_sprintf("SSL_CTX_new() failed: %s", ssl_errstring); | |
2855 | } | |
2856 | ||
2857 | DEBUG(D_tls) | |
2858 | debug_printf("tls_require_ciphers expands to \"%s\"\n", expciphers); | |
2859 | ||
2860 | if (!SSL_CTX_set_cipher_list(ctx, CS expciphers)) | |
2861 | { | |
2862 | ERR_error_string(ERR_get_error(), ssl_errstring); | |
cf0c6164 JH |
2863 | err = string_sprintf("SSL_CTX_set_cipher_list(%s) failed: %s", |
2864 | expciphers, ssl_errstring); | |
3375e053 PP |
2865 | } |
2866 | ||
2867 | SSL_CTX_free(ctx); | |
2868 | ||
2869 | return err; | |
2870 | } | |
2871 | ||
2872 | ||
2873 | ||
2874 | ||
36f12725 NM |
2875 | /************************************************* |
2876 | * Report the library versions. * | |
2877 | *************************************************/ | |
2878 | ||
2879 | /* There have historically been some issues with binary compatibility in | |
2880 | OpenSSL libraries; if Exim (like many other applications) is built against | |
2881 | one version of OpenSSL but the run-time linker picks up another version, | |
2882 | it can result in serious failures, including crashing with a SIGSEGV. So | |
2883 | report the version found by the compiler and the run-time version. | |
2884 | ||
f64a1e23 PP |
2885 | Note: some OS vendors backport security fixes without changing the version |
2886 | number/string, and the version date remains unchanged. The _build_ date | |
2887 | will change, so we can more usefully assist with version diagnosis by also | |
2888 | reporting the build date. | |
2889 | ||
36f12725 NM |
2890 | Arguments: a FILE* to print the results to |
2891 | Returns: nothing | |
2892 | */ | |
2893 | ||
2894 | void | |
2895 | tls_version_report(FILE *f) | |
2896 | { | |
754a0503 | 2897 | fprintf(f, "Library version: OpenSSL: Compile: %s\n" |
f64a1e23 PP |
2898 | " Runtime: %s\n" |
2899 | " : %s\n", | |
754a0503 | 2900 | OPENSSL_VERSION_TEXT, |
f64a1e23 PP |
2901 | SSLeay_version(SSLEAY_VERSION), |
2902 | SSLeay_version(SSLEAY_BUILT_ON)); | |
2903 | /* third line is 38 characters for the %s and the line is 73 chars long; | |
2904 | the OpenSSL output includes a "built on: " prefix already. */ | |
36f12725 NM |
2905 | } |
2906 | ||
9e3331ea TK |
2907 | |
2908 | ||
2909 | ||
2910 | /************************************************* | |
17c76198 | 2911 | * Random number generation * |
9e3331ea TK |
2912 | *************************************************/ |
2913 | ||
2914 | /* Pseudo-random number generation. The result is not expected to be | |
2915 | cryptographically strong but not so weak that someone will shoot themselves | |
2916 | in the foot using it as a nonce in input in some email header scheme or | |
2917 | whatever weirdness they'll twist this into. The result should handle fork() | |
2918 | and avoid repeating sequences. OpenSSL handles that for us. | |
2919 | ||
2920 | Arguments: | |
2921 | max range maximum | |
2922 | Returns a random number in range [0, max-1] | |
2923 | */ | |
2924 | ||
2925 | int | |
17c76198 | 2926 | vaguely_random_number(int max) |
9e3331ea TK |
2927 | { |
2928 | unsigned int r; | |
2929 | int i, needed_len; | |
de6135a0 PP |
2930 | static pid_t pidlast = 0; |
2931 | pid_t pidnow; | |
9e3331ea TK |
2932 | uschar *p; |
2933 | uschar smallbuf[sizeof(r)]; | |
2934 | ||
2935 | if (max <= 1) | |
2936 | return 0; | |
2937 | ||
de6135a0 PP |
2938 | pidnow = getpid(); |
2939 | if (pidnow != pidlast) | |
2940 | { | |
2941 | /* Although OpenSSL documents that "OpenSSL makes sure that the PRNG state | |
2942 | is unique for each thread", this doesn't apparently apply across processes, | |
2943 | so our own warning from vaguely_random_number_fallback() applies here too. | |
2944 | Fix per PostgreSQL. */ | |
2945 | if (pidlast != 0) | |
2946 | RAND_cleanup(); | |
2947 | pidlast = pidnow; | |
2948 | } | |
2949 | ||
9e3331ea TK |
2950 | /* OpenSSL auto-seeds from /dev/random, etc, but this a double-check. */ |
2951 | if (!RAND_status()) | |
2952 | { | |
2953 | randstuff r; | |
2954 | gettimeofday(&r.tv, NULL); | |
2955 | r.p = getpid(); | |
2956 | ||
5903c6ff | 2957 | RAND_seed(US (&r), sizeof(r)); |
9e3331ea TK |
2958 | } |
2959 | /* We're after pseudo-random, not random; if we still don't have enough data | |
2960 | in the internal PRNG then our options are limited. We could sleep and hope | |
2961 | for entropy to come along (prayer technique) but if the system is so depleted | |
2962 | in the first place then something is likely to just keep taking it. Instead, | |
2963 | we'll just take whatever little bit of pseudo-random we can still manage to | |
2964 | get. */ | |
2965 | ||
2966 | needed_len = sizeof(r); | |
2967 | /* Don't take 8 times more entropy than needed if int is 8 octets and we were | |
2968 | asked for a number less than 10. */ | |
2969 | for (r = max, i = 0; r; ++i) | |
2970 | r >>= 1; | |
2971 | i = (i + 7) / 8; | |
2972 | if (i < needed_len) | |
2973 | needed_len = i; | |
2974 | ||
c8dfb21d | 2975 | #ifdef EXIM_HAVE_RAND_PSEUDO |
9e3331ea | 2976 | /* We do not care if crypto-strong */ |
17c76198 | 2977 | i = RAND_pseudo_bytes(smallbuf, needed_len); |
c8dfb21d JH |
2978 | #else |
2979 | i = RAND_bytes(smallbuf, needed_len); | |
2980 | #endif | |
2981 | ||
17c76198 PP |
2982 | if (i < 0) |
2983 | { | |
2984 | DEBUG(D_all) | |
2985 | debug_printf("OpenSSL RAND_pseudo_bytes() not supported by RAND method, using fallback.\n"); | |
2986 | return vaguely_random_number_fallback(max); | |
2987 | } | |
2988 | ||
9e3331ea TK |
2989 | r = 0; |
2990 | for (p = smallbuf; needed_len; --needed_len, ++p) | |
2991 | { | |
2992 | r *= 256; | |
2993 | r += *p; | |
2994 | } | |
2995 | ||
2996 | /* We don't particularly care about weighted results; if someone wants | |
2997 | smooth distribution and cares enough then they should submit a patch then. */ | |
2998 | return r % max; | |
2999 | } | |
3000 | ||
77bb000f PP |
3001 | |
3002 | ||
3003 | ||
3004 | /************************************************* | |
3005 | * OpenSSL option parse * | |
3006 | *************************************************/ | |
3007 | ||
3008 | /* Parse one option for tls_openssl_options_parse below | |
3009 | ||
3010 | Arguments: | |
3011 | name one option name | |
3012 | value place to store a value for it | |
3013 | Returns success or failure in parsing | |
3014 | */ | |
3015 | ||
3016 | struct exim_openssl_option { | |
3017 | uschar *name; | |
3018 | long value; | |
3019 | }; | |
3020 | /* We could use a macro to expand, but we need the ifdef and not all the | |
3021 | options document which version they were introduced in. Policylet: include | |
3022 | all options unless explicitly for DTLS, let the administrator choose which | |
3023 | to apply. | |
3024 | ||
3025 | This list is current as of: | |
e2fbf4a2 PP |
3026 | ==> 1.0.1b <== |
3027 | Plus SSL_OP_SAFARI_ECDHE_ECDSA_BUG from 2013-June patch/discussion on openssl-dev | |
3028 | */ | |
77bb000f PP |
3029 | static struct exim_openssl_option exim_openssl_options[] = { |
3030 | /* KEEP SORTED ALPHABETICALLY! */ | |
3031 | #ifdef SSL_OP_ALL | |
73a46702 | 3032 | { US"all", SSL_OP_ALL }, |
77bb000f PP |
3033 | #endif |
3034 | #ifdef SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION | |
73a46702 | 3035 | { US"allow_unsafe_legacy_renegotiation", SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION }, |
77bb000f PP |
3036 | #endif |
3037 | #ifdef SSL_OP_CIPHER_SERVER_PREFERENCE | |
73a46702 | 3038 | { US"cipher_server_preference", SSL_OP_CIPHER_SERVER_PREFERENCE }, |
77bb000f PP |
3039 | #endif |
3040 | #ifdef SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS | |
73a46702 | 3041 | { US"dont_insert_empty_fragments", SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS }, |
77bb000f PP |
3042 | #endif |
3043 | #ifdef SSL_OP_EPHEMERAL_RSA | |
73a46702 | 3044 | { US"ephemeral_rsa", SSL_OP_EPHEMERAL_RSA }, |
77bb000f PP |
3045 | #endif |
3046 | #ifdef SSL_OP_LEGACY_SERVER_CONNECT | |
73a46702 | 3047 | { US"legacy_server_connect", SSL_OP_LEGACY_SERVER_CONNECT }, |
77bb000f PP |
3048 | #endif |
3049 | #ifdef SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER | |
73a46702 | 3050 | { US"microsoft_big_sslv3_buffer", SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER }, |
77bb000f PP |
3051 | #endif |
3052 | #ifdef SSL_OP_MICROSOFT_SESS_ID_BUG | |
73a46702 | 3053 | { US"microsoft_sess_id_bug", SSL_OP_MICROSOFT_SESS_ID_BUG }, |
77bb000f PP |
3054 | #endif |
3055 | #ifdef SSL_OP_MSIE_SSLV2_RSA_PADDING | |
73a46702 | 3056 | { US"msie_sslv2_rsa_padding", SSL_OP_MSIE_SSLV2_RSA_PADDING }, |
77bb000f PP |
3057 | #endif |
3058 | #ifdef SSL_OP_NETSCAPE_CHALLENGE_BUG | |
73a46702 | 3059 | { US"netscape_challenge_bug", SSL_OP_NETSCAPE_CHALLENGE_BUG }, |
77bb000f PP |
3060 | #endif |
3061 | #ifdef SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG | |
73a46702 | 3062 | { US"netscape_reuse_cipher_change_bug", SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG }, |
77bb000f | 3063 | #endif |
c80c5570 PP |
3064 | #ifdef SSL_OP_NO_COMPRESSION |
3065 | { US"no_compression", SSL_OP_NO_COMPRESSION }, | |
3066 | #endif | |
77bb000f | 3067 | #ifdef SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION |
73a46702 | 3068 | { US"no_session_resumption_on_renegotiation", SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION }, |
77bb000f | 3069 | #endif |
c0c7b2da PP |
3070 | #ifdef SSL_OP_NO_SSLv2 |
3071 | { US"no_sslv2", SSL_OP_NO_SSLv2 }, | |
3072 | #endif | |
3073 | #ifdef SSL_OP_NO_SSLv3 | |
3074 | { US"no_sslv3", SSL_OP_NO_SSLv3 }, | |
3075 | #endif | |
3076 | #ifdef SSL_OP_NO_TICKET | |
3077 | { US"no_ticket", SSL_OP_NO_TICKET }, | |
3078 | #endif | |
3079 | #ifdef SSL_OP_NO_TLSv1 | |
3080 | { US"no_tlsv1", SSL_OP_NO_TLSv1 }, | |
3081 | #endif | |
c80c5570 PP |
3082 | #ifdef SSL_OP_NO_TLSv1_1 |
3083 | #if SSL_OP_NO_TLSv1_1 == 0x00000400L | |
3084 | /* Error in chosen value in 1.0.1a; see first item in CHANGES for 1.0.1b */ | |
3085 | #warning OpenSSL 1.0.1a uses a bad value for SSL_OP_NO_TLSv1_1, ignoring | |
3086 | #else | |
3087 | { US"no_tlsv1_1", SSL_OP_NO_TLSv1_1 }, | |
3088 | #endif | |
3089 | #endif | |
3090 | #ifdef SSL_OP_NO_TLSv1_2 | |
3091 | { US"no_tlsv1_2", SSL_OP_NO_TLSv1_2 }, | |
3092 | #endif | |
e2fbf4a2 PP |
3093 | #ifdef SSL_OP_SAFARI_ECDHE_ECDSA_BUG |
3094 | { US"safari_ecdhe_ecdsa_bug", SSL_OP_SAFARI_ECDHE_ECDSA_BUG }, | |
3095 | #endif | |
77bb000f | 3096 | #ifdef SSL_OP_SINGLE_DH_USE |
73a46702 | 3097 | { US"single_dh_use", SSL_OP_SINGLE_DH_USE }, |
77bb000f PP |
3098 | #endif |
3099 | #ifdef SSL_OP_SINGLE_ECDH_USE | |
73a46702 | 3100 | { US"single_ecdh_use", SSL_OP_SINGLE_ECDH_USE }, |
77bb000f PP |
3101 | #endif |
3102 | #ifdef SSL_OP_SSLEAY_080_CLIENT_DH_BUG | |
73a46702 | 3103 | { US"ssleay_080_client_dh_bug", SSL_OP_SSLEAY_080_CLIENT_DH_BUG }, |
77bb000f PP |
3104 | #endif |
3105 | #ifdef SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG | |
73a46702 | 3106 | { US"sslref2_reuse_cert_type_bug", SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG }, |
77bb000f PP |
3107 | #endif |
3108 | #ifdef SSL_OP_TLS_BLOCK_PADDING_BUG | |
73a46702 | 3109 | { US"tls_block_padding_bug", SSL_OP_TLS_BLOCK_PADDING_BUG }, |
77bb000f PP |
3110 | #endif |
3111 | #ifdef SSL_OP_TLS_D5_BUG | |
73a46702 | 3112 | { US"tls_d5_bug", SSL_OP_TLS_D5_BUG }, |
77bb000f PP |
3113 | #endif |
3114 | #ifdef SSL_OP_TLS_ROLLBACK_BUG | |
73a46702 | 3115 | { US"tls_rollback_bug", SSL_OP_TLS_ROLLBACK_BUG }, |
77bb000f PP |
3116 | #endif |
3117 | }; | |
3118 | static int exim_openssl_options_size = | |
3119 | sizeof(exim_openssl_options)/sizeof(struct exim_openssl_option); | |
3120 | ||
c80c5570 | 3121 | |
77bb000f PP |
3122 | static BOOL |
3123 | tls_openssl_one_option_parse(uschar *name, long *value) | |
3124 | { | |
3125 | int first = 0; | |
3126 | int last = exim_openssl_options_size; | |
3127 | while (last > first) | |
3128 | { | |
3129 | int middle = (first + last)/2; | |
3130 | int c = Ustrcmp(name, exim_openssl_options[middle].name); | |
3131 | if (c == 0) | |
3132 | { | |
3133 | *value = exim_openssl_options[middle].value; | |
3134 | return TRUE; | |
3135 | } | |
3136 | else if (c > 0) | |
3137 | first = middle + 1; | |
3138 | else | |
3139 | last = middle; | |
3140 | } | |
3141 | return FALSE; | |
3142 | } | |
3143 | ||
3144 | ||
3145 | ||
3146 | ||
3147 | /************************************************* | |
3148 | * OpenSSL option parsing logic * | |
3149 | *************************************************/ | |
3150 | ||
3151 | /* OpenSSL has a number of compatibility options which an administrator might | |
3152 | reasonably wish to set. Interpret a list similarly to decode_bits(), so that | |
3153 | we look like log_selector. | |
3154 | ||
3155 | Arguments: | |
3156 | option_spec the administrator-supplied string of options | |
3157 | results ptr to long storage for the options bitmap | |
3158 | Returns success or failure | |
3159 | */ | |
3160 | ||
3161 | BOOL | |
3162 | tls_openssl_options_parse(uschar *option_spec, long *results) | |
3163 | { | |
3164 | long result, item; | |
3165 | uschar *s, *end; | |
3166 | uschar keep_c; | |
3167 | BOOL adding, item_parsed; | |
3168 | ||
7006ee24 | 3169 | result = SSL_OP_NO_TICKET; |
b1770b6e | 3170 | /* Prior to 4.80 we or'd in SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS; removed |
da3ad30d | 3171 | * from default because it increases BEAST susceptibility. */ |
f0f5a555 PP |
3172 | #ifdef SSL_OP_NO_SSLv2 |
3173 | result |= SSL_OP_NO_SSLv2; | |
3174 | #endif | |
a57b6200 JH |
3175 | #ifdef SSL_OP_SINGLE_DH_USE |
3176 | result |= SSL_OP_SINGLE_DH_USE; | |
3177 | #endif | |
77bb000f | 3178 | |
7006ee24 | 3179 | if (!option_spec) |
77bb000f PP |
3180 | { |
3181 | *results = result; | |
3182 | return TRUE; | |
3183 | } | |
3184 | ||
3185 | for (s=option_spec; *s != '\0'; /**/) | |
3186 | { | |
3187 | while (isspace(*s)) ++s; | |
3188 | if (*s == '\0') | |
3189 | break; | |
3190 | if (*s != '+' && *s != '-') | |
3191 | { | |
3192 | DEBUG(D_tls) debug_printf("malformed openssl option setting: " | |
0e944a0d | 3193 | "+ or - expected but found \"%s\"\n", s); |
77bb000f PP |
3194 | return FALSE; |
3195 | } | |
3196 | adding = *s++ == '+'; | |
3197 | for (end = s; (*end != '\0') && !isspace(*end); ++end) /**/ ; | |
3198 | keep_c = *end; | |
3199 | *end = '\0'; | |
3200 | item_parsed = tls_openssl_one_option_parse(s, &item); | |
96f5fe4c | 3201 | *end = keep_c; |
77bb000f PP |
3202 | if (!item_parsed) |
3203 | { | |
0e944a0d | 3204 | DEBUG(D_tls) debug_printf("openssl option setting unrecognised: \"%s\"\n", s); |
77bb000f PP |
3205 | return FALSE; |
3206 | } | |
3207 | DEBUG(D_tls) debug_printf("openssl option, %s from %lx: %lx (%s)\n", | |
3208 | adding ? "adding" : "removing", result, item, s); | |
3209 | if (adding) | |
3210 | result |= item; | |
3211 | else | |
3212 | result &= ~item; | |
77bb000f PP |
3213 | s = end; |
3214 | } | |
3215 | ||
3216 | *results = result; | |
3217 | return TRUE; | |
3218 | } | |
3219 | ||
9d1c15ef JH |
3220 | /* vi: aw ai sw=2 |
3221 | */ | |
059ec3d9 | 3222 | /* End of tls-openssl.c */ |