Commit | Line | Data |
---|---|---|
059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
9242a7e8 | 5 | /* Copyright (c) University of Cambridge 1995 - 2017 */ |
059ec3d9 PH |
6 | /* See the file NOTICE for conditions of use and distribution. */ |
7 | ||
17c76198 | 8 | /* Copyright (c) Phil Pennock 2012 */ |
059ec3d9 | 9 | |
17c76198 PP |
10 | /* This file provides TLS/SSL support for Exim using the GnuTLS library, |
11 | one of the available supported implementations. This file is #included into | |
12 | tls.c when USE_GNUTLS has been set. | |
059ec3d9 | 13 | |
17c76198 PP |
14 | The code herein is a revamp of GnuTLS integration using the current APIs; the |
15 | original tls-gnu.c was based on a patch which was contributed by Nikos | |
6aa6fc9c | 16 | Mavrogiannopoulos. The revamp is partially a rewrite, partially cut&paste as |
17c76198 | 17 | appropriate. |
059ec3d9 | 18 | |
17c76198 PP |
19 | APIs current as of GnuTLS 2.12.18; note that the GnuTLS manual is for GnuTLS 3, |
20 | which is not widely deployed by OS vendors. Will note issues below, which may | |
21 | assist in updating the code in the future. Another sources of hints is | |
22 | mod_gnutls for Apache (SNI callback registration and handling). | |
059ec3d9 | 23 | |
17c76198 PP |
24 | Keeping client and server variables more split than before and is currently |
25 | the norm, in anticipation of TLS in ACL callouts. | |
059ec3d9 | 26 | |
17c76198 PP |
27 | I wanted to switch to gnutls_certificate_set_verify_function() so that |
28 | certificate rejection could happen during handshake where it belongs, rather | |
29 | than being dropped afterwards, but that was introduced in 2.10.0 and Debian | |
30 | (6.0.5) is still on 2.8.6. So for now we have to stick with sub-par behaviour. | |
059ec3d9 | 31 | |
17c76198 PP |
32 | (I wasn't looking for libraries quite that old, when updating to get rid of |
33 | compiler warnings of deprecated APIs. If it turns out that a lot of the rest | |
34 | require current GnuTLS, then we'll drop support for the ancient libraries). | |
35 | */ | |
b5aea5e1 | 36 | |
17c76198 PP |
37 | #include <gnutls/gnutls.h> |
38 | /* needed for cert checks in verification and DN extraction: */ | |
39 | #include <gnutls/x509.h> | |
40 | /* man-page is incorrect, gnutls_rnd() is not in gnutls.h: */ | |
41 | #include <gnutls/crypto.h> | |
a5f239e4 PP |
42 | /* needed to disable PKCS11 autoload unless requested */ |
43 | #if GNUTLS_VERSION_NUMBER >= 0x020c00 | |
44 | # include <gnutls/pkcs11.h> | |
76075bb5 | 45 | # define SUPPORT_PARAM_TO_PK_BITS |
a5f239e4 | 46 | #endif |
7e07527a JH |
47 | #if GNUTLS_VERSION_NUMBER < 0x030103 && !defined(DISABLE_OCSP) |
48 | # warning "GnuTLS library version too old; define DISABLE_OCSP in Makefile" | |
49 | # define DISABLE_OCSP | |
50 | #endif | |
0cbf2b82 | 51 | #if GNUTLS_VERSION_NUMBER < 0x020a00 && !defined(DISABLE_EVENT) |
774ef2d7 | 52 | # warning "GnuTLS library version too old; tls:cert event unsupported" |
0cbf2b82 | 53 | # define DISABLE_EVENT |
a7538db1 | 54 | #endif |
a7fec7a7 JH |
55 | #if GNUTLS_VERSION_NUMBER >= 0x030306 |
56 | # define SUPPORT_CA_DIR | |
57 | #else | |
58 | # undef SUPPORT_CA_DIR | |
59 | #endif | |
11a04b5a | 60 | #if GNUTLS_VERSION_NUMBER >= 0x030014 |
cb1d7830 JH |
61 | # define SUPPORT_SYSDEFAULT_CABUNDLE |
62 | #endif | |
925ac8e4 JH |
63 | #if GNUTLS_VERSION_NUMBER >= 0x030109 |
64 | # define SUPPORT_CORK | |
65 | #endif | |
47195144 JH |
66 | #if GNUTLS_VERSION_NUMBER >= 0x030506 && !defined(DISABLE_OCSP) |
67 | # define SUPPORT_SRV_OCSP_STACK | |
68 | #endif | |
899b8bbc JH |
69 | #if GNUTLS_VERSION_NUMBER >= 0x030000 && defined(EXPERIMENTAL_DANE) |
70 | # define SUPPORT_DANE | |
71 | #endif | |
7e07527a | 72 | |
f2de3a33 | 73 | #ifndef DISABLE_OCSP |
2b4a568d JH |
74 | # include <gnutls/ocsp.h> |
75 | #endif | |
899b8bbc JH |
76 | #ifdef SUPPORT_DANE |
77 | # include <gnutls/dane.h> | |
78 | #endif | |
059ec3d9 | 79 | |
17c76198 | 80 | /* GnuTLS 2 vs 3 |
059ec3d9 | 81 | |
17c76198 PP |
82 | GnuTLS 3 only: |
83 | gnutls_global_set_audit_log_function() | |
059ec3d9 | 84 | |
17c76198 PP |
85 | Changes: |
86 | gnutls_certificate_verify_peers2(): is new, drop the 2 for old version | |
87 | */ | |
059ec3d9 | 88 | |
17c76198 | 89 | /* Local static variables for GnuTLS */ |
059ec3d9 | 90 | |
17c76198 | 91 | /* Values for verify_requirement */ |
059ec3d9 | 92 | |
e51c7be2 | 93 | enum peer_verify_requirement |
899b8bbc | 94 | { VERIFY_NONE, VERIFY_OPTIONAL, VERIFY_REQUIRED, VERIFY_DANE }; |
059ec3d9 | 95 | |
17c76198 PP |
96 | /* This holds most state for server or client; with this, we can set up an |
97 | outbound TLS-enabled connection in an ACL callout, while not stomping all | |
98 | over the TLS variables available for expansion. | |
059ec3d9 | 99 | |
17c76198 PP |
100 | Some of these correspond to variables in globals.c; those variables will |
101 | be set to point to content in one of these instances, as appropriate for | |
102 | the stage of the process lifetime. | |
059ec3d9 | 103 | |
389ca47a | 104 | Not handled here: global tls_channelbinding_b64. |
17c76198 | 105 | */ |
059ec3d9 | 106 | |
17c76198 | 107 | typedef struct exim_gnutls_state { |
9d1c15ef | 108 | gnutls_session_t session; |
17c76198 | 109 | gnutls_certificate_credentials_t x509_cred; |
9d1c15ef | 110 | gnutls_priority_t priority_cache; |
17c76198 | 111 | enum peer_verify_requirement verify_requirement; |
9d1c15ef JH |
112 | int fd_in; |
113 | int fd_out; | |
114 | BOOL peer_cert_verified; | |
899b8bbc | 115 | BOOL peer_dane_verified; |
9d1c15ef JH |
116 | BOOL trigger_sni_changes; |
117 | BOOL have_set_peerdn; | |
17c76198 | 118 | const struct host_item *host; |
9d1c15ef JH |
119 | gnutls_x509_crt_t peercert; |
120 | uschar *peerdn; | |
121 | uschar *ciphersuite; | |
122 | uschar *received_sni; | |
17c76198 PP |
123 | |
124 | const uschar *tls_certificate; | |
125 | const uschar *tls_privatekey; | |
126 | const uschar *tls_sni; /* client send only, not received */ | |
127 | const uschar *tls_verify_certificates; | |
128 | const uschar *tls_crl; | |
129 | const uschar *tls_require_ciphers; | |
e51c7be2 | 130 | |
17c76198 PP |
131 | uschar *exp_tls_certificate; |
132 | uschar *exp_tls_privatekey; | |
17c76198 PP |
133 | uschar *exp_tls_verify_certificates; |
134 | uschar *exp_tls_crl; | |
135 | uschar *exp_tls_require_ciphers; | |
55414b25 | 136 | const uschar *exp_tls_verify_cert_hostnames; |
0cbf2b82 | 137 | #ifndef DISABLE_EVENT |
a7538db1 JH |
138 | uschar *event_action; |
139 | #endif | |
899b8bbc JH |
140 | #ifdef SUPPORT_DANE |
141 | char * const * dane_data; | |
142 | const int * dane_data_len; | |
143 | #endif | |
17c76198 | 144 | |
389ca47a | 145 | tls_support *tlsp; /* set in tls_init() */ |
817d9f57 | 146 | |
17c76198 PP |
147 | uschar *xfer_buffer; |
148 | int xfer_buffer_lwm; | |
149 | int xfer_buffer_hwm; | |
150 | int xfer_eof; | |
151 | int xfer_error; | |
17c76198 PP |
152 | } exim_gnutls_state_st; |
153 | ||
154 | static const exim_gnutls_state_st exim_gnutls_state_init = { | |
f2ed27cf JH |
155 | .session = NULL, |
156 | .x509_cred = NULL, | |
157 | .priority_cache = NULL, | |
158 | .verify_requirement = VERIFY_NONE, | |
159 | .fd_in = -1, | |
160 | .fd_out = -1, | |
161 | .peer_cert_verified = FALSE, | |
899b8bbc | 162 | .peer_dane_verified = FALSE, |
f2ed27cf JH |
163 | .trigger_sni_changes =FALSE, |
164 | .have_set_peerdn = FALSE, | |
165 | .host = NULL, | |
166 | .peercert = NULL, | |
167 | .peerdn = NULL, | |
168 | .ciphersuite = NULL, | |
169 | .received_sni = NULL, | |
170 | ||
171 | .tls_certificate = NULL, | |
172 | .tls_privatekey = NULL, | |
173 | .tls_sni = NULL, | |
174 | .tls_verify_certificates = NULL, | |
175 | .tls_crl = NULL, | |
176 | .tls_require_ciphers =NULL, | |
177 | ||
178 | .exp_tls_certificate = NULL, | |
179 | .exp_tls_privatekey = NULL, | |
180 | .exp_tls_verify_certificates = NULL, | |
181 | .exp_tls_crl = NULL, | |
182 | .exp_tls_require_ciphers = NULL, | |
f2ed27cf | 183 | .exp_tls_verify_cert_hostnames = NULL, |
0cbf2b82 | 184 | #ifndef DISABLE_EVENT |
f2ed27cf | 185 | .event_action = NULL, |
e51c7be2 | 186 | #endif |
f2ed27cf JH |
187 | .tlsp = NULL, |
188 | ||
189 | .xfer_buffer = NULL, | |
190 | .xfer_buffer_lwm = 0, | |
191 | .xfer_buffer_hwm = 0, | |
192 | .xfer_eof = 0, | |
193 | .xfer_error = 0, | |
17c76198 | 194 | }; |
83da1223 | 195 | |
17c76198 PP |
196 | /* Not only do we have our own APIs which don't pass around state, assuming |
197 | it's held in globals, GnuTLS doesn't appear to let us register callback data | |
198 | for callbacks, or as part of the session, so we have to keep a "this is the | |
199 | context we're currently dealing with" pointer and rely upon being | |
200 | single-threaded to keep from processing data on an inbound TLS connection while | |
201 | talking to another TLS connection for an outbound check. This does mean that | |
202 | there's no way for heart-beats to be responded to, for the duration of the | |
a7538db1 JH |
203 | second connection. |
204 | XXX But see gnutls_session_get_ptr() | |
205 | */ | |
059ec3d9 | 206 | |
17c76198 | 207 | static exim_gnutls_state_st state_server, state_client; |
059ec3d9 | 208 | |
17c76198 PP |
209 | /* dh_params are initialised once within the lifetime of a process using TLS; |
210 | if we used TLS in a long-lived daemon, we'd have to reconsider this. But we | |
211 | don't want to repeat this. */ | |
83da1223 | 212 | |
17c76198 | 213 | static gnutls_dh_params_t dh_server_params = NULL; |
059ec3d9 | 214 | |
17c76198 | 215 | /* No idea how this value was chosen; preserving it. Default is 3600. */ |
059ec3d9 | 216 | |
17c76198 | 217 | static const int ssl_session_timeout = 200; |
059ec3d9 | 218 | |
17c76198 | 219 | static const char * const exim_default_gnutls_priority = "NORMAL"; |
83da1223 | 220 | |
17c76198 | 221 | /* Guard library core initialisation */ |
83da1223 | 222 | |
17c76198 | 223 | static BOOL exim_gnutls_base_init_done = FALSE; |
059ec3d9 | 224 | |
4fb7df6d | 225 | #ifndef DISABLE_OCSP |
9196d5bf | 226 | static BOOL gnutls_buggy_ocsp = FALSE; |
4fb7df6d | 227 | #endif |
9196d5bf | 228 | |
059ec3d9 | 229 | |
17c76198 PP |
230 | /* ------------------------------------------------------------------------ */ |
231 | /* macros */ | |
83da1223 | 232 | |
17c76198 | 233 | #define MAX_HOST_LEN 255 |
83da1223 | 234 | |
17c76198 PP |
235 | /* Set this to control gnutls_global_set_log_level(); values 0 to 9 will setup |
236 | the library logging; a value less than 0 disables the calls to set up logging | |
ef9da2ee JH |
237 | callbacks. Possibly GNuTLS also looks for an environment variable |
238 | "GNUTLS_DEBUG_LEVEL". */ | |
2c17bb02 | 239 | #ifndef EXIM_GNUTLS_LIBRARY_LOG_LEVEL |
a7538db1 | 240 | # define EXIM_GNUTLS_LIBRARY_LOG_LEVEL -1 |
2c17bb02 | 241 | #endif |
83da1223 | 242 | |
2c17bb02 | 243 | #ifndef EXIM_CLIENT_DH_MIN_BITS |
a7538db1 | 244 | # define EXIM_CLIENT_DH_MIN_BITS 1024 |
2c17bb02 | 245 | #endif |
83da1223 | 246 | |
af3498d6 PP |
247 | /* With GnuTLS 2.12.x+ we have gnutls_sec_param_to_pk_bits() with which we |
248 | can ask for a bit-strength. Without that, we stick to the constant we had | |
249 | before, for now. */ | |
2c17bb02 | 250 | #ifndef EXIM_SERVER_DH_BITS_PRE2_12 |
a7538db1 | 251 | # define EXIM_SERVER_DH_BITS_PRE2_12 1024 |
2c17bb02 | 252 | #endif |
af3498d6 | 253 | |
47195144 JH |
254 | #define exim_gnutls_err_check(rc, Label) do { \ |
255 | if ((rc) != GNUTLS_E_SUCCESS) \ | |
cf0c6164 JH |
256 | return tls_error((Label), gnutls_strerror(rc), host, errstr); \ |
257 | } while (0) | |
059ec3d9 | 258 | |
cf0c6164 JH |
259 | #define expand_check_tlsvar(Varname, errstr) \ |
260 | expand_check(state->Varname, US #Varname, &state->exp_##Varname, errstr) | |
83da1223 | 261 | |
17c76198 | 262 | #if GNUTLS_VERSION_NUMBER >= 0x020c00 |
e51c7be2 JH |
263 | # define HAVE_GNUTLS_SESSION_CHANNEL_BINDING |
264 | # define HAVE_GNUTLS_SEC_PARAM_CONSTANTS | |
265 | # define HAVE_GNUTLS_RND | |
2519e60d TL |
266 | /* The security fix we provide with the gnutls_allow_auto_pkcs11 option |
267 | * (4.82 PP/09) introduces a compatibility regression. The symbol simply | |
268 | * isn't available sometimes, so this needs to become a conditional | |
269 | * compilation; the sanest way to deal with this being a problem on | |
270 | * older OSes is to block it in the Local/Makefile with this compiler | |
271 | * definition */ | |
e51c7be2 JH |
272 | # ifndef AVOID_GNUTLS_PKCS11 |
273 | # define HAVE_GNUTLS_PKCS11 | |
274 | # endif /* AVOID_GNUTLS_PKCS11 */ | |
17c76198 | 275 | #endif |
83da1223 | 276 | |
af3498d6 PP |
277 | |
278 | ||
279 | ||
280 | /* ------------------------------------------------------------------------ */ | |
281 | /* Callback declarations */ | |
282 | ||
283 | #if EXIM_GNUTLS_LIBRARY_LOG_LEVEL >= 0 | |
284 | static void exim_gnutls_logger_cb(int level, const char *message); | |
285 | #endif | |
286 | ||
287 | static int exim_sni_handling_cb(gnutls_session_t session); | |
288 | ||
f2de3a33 | 289 | #ifndef DISABLE_OCSP |
44662487 JH |
290 | static int server_ocsp_stapling_cb(gnutls_session_t session, void * ptr, |
291 | gnutls_datum_t * ocsp_response); | |
292 | #endif | |
af3498d6 PP |
293 | |
294 | ||
295 | ||
17c76198 PP |
296 | /* ------------------------------------------------------------------------ */ |
297 | /* Static functions */ | |
059ec3d9 PH |
298 | |
299 | /************************************************* | |
300 | * Handle TLS error * | |
301 | *************************************************/ | |
302 | ||
303 | /* Called from lots of places when errors occur before actually starting to do | |
304 | the TLS handshake, that is, while the session is still in clear. Always returns | |
305 | DEFER for a server and FAIL for a client so that most calls can use "return | |
306 | tls_error(...)" to do this processing and then give an appropriate return. A | |
307 | single function is used for both server and client, because it is called from | |
308 | some shared functions. | |
309 | ||
310 | Argument: | |
311 | prefix text to include in the logged error | |
7199e1ee TF |
312 | msg additional error string (may be NULL) |
313 | usually obtained from gnutls_strerror() | |
17c76198 PP |
314 | host NULL if setting up a server; |
315 | the connected host if setting up a client | |
cf0c6164 | 316 | errstr pointer to returned error string |
059ec3d9 PH |
317 | |
318 | Returns: OK/DEFER/FAIL | |
319 | */ | |
320 | ||
321 | static int | |
cf0c6164 JH |
322 | tls_error(const uschar *prefix, const char *msg, const host_item *host, |
323 | uschar ** errstr) | |
059ec3d9 | 324 | { |
cf0c6164 JH |
325 | if (errstr) |
326 | *errstr = string_sprintf("(%s)%s%s", prefix, msg ? ": " : "", msg ? msg : ""); | |
327 | return host ? FAIL : DEFER; | |
059ec3d9 PH |
328 | } |
329 | ||
330 | ||
331 | ||
17c76198 | 332 | |
059ec3d9 | 333 | /************************************************* |
17c76198 | 334 | * Deal with logging errors during I/O * |
059ec3d9 PH |
335 | *************************************************/ |
336 | ||
17c76198 | 337 | /* We have to get the identity of the peer from saved data. |
059ec3d9 | 338 | |
17c76198 PP |
339 | Argument: |
340 | state the current GnuTLS exim state container | |
341 | rc the GnuTLS error code, or 0 if it's a local error | |
342 | when text identifying read or write | |
343 | text local error text when ec is 0 | |
059ec3d9 | 344 | |
17c76198 | 345 | Returns: nothing |
059ec3d9 PH |
346 | */ |
347 | ||
17c76198 PP |
348 | static void |
349 | record_io_error(exim_gnutls_state_st *state, int rc, uschar *when, uschar *text) | |
059ec3d9 | 350 | { |
cf0c6164 JH |
351 | const char * msg; |
352 | uschar * errstr; | |
059ec3d9 | 353 | |
17c76198 PP |
354 | if (rc == GNUTLS_E_FATAL_ALERT_RECEIVED) |
355 | msg = CS string_sprintf("%s: %s", US gnutls_strerror(rc), | |
356 | US gnutls_alert_get_name(gnutls_alert_get(state->session))); | |
357 | else | |
358 | msg = gnutls_strerror(rc); | |
059ec3d9 | 359 | |
cf0c6164 JH |
360 | (void) tls_error(when, msg, state->host, &errstr); |
361 | ||
362 | if (state->host) | |
363 | log_write(0, LOG_MAIN, "H=%s [%s] TLS error on connection %s", | |
364 | state->host->name, state->host->address, errstr); | |
365 | else | |
366 | { | |
367 | uschar * conn_info = smtp_get_connection_info(); | |
368 | if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) conn_info += 5; | |
369 | /* I'd like to get separated H= here, but too hard for now */ | |
370 | log_write(0, LOG_MAIN, "TLS error on %s %s", conn_info, errstr); | |
371 | } | |
17c76198 | 372 | } |
059ec3d9 | 373 | |
059ec3d9 | 374 | |
059ec3d9 | 375 | |
059ec3d9 | 376 | |
17c76198 PP |
377 | /************************************************* |
378 | * Set various Exim expansion vars * | |
379 | *************************************************/ | |
059ec3d9 | 380 | |
e51c7be2 JH |
381 | #define exim_gnutls_cert_err(Label) \ |
382 | do \ | |
383 | { \ | |
384 | if (rc != GNUTLS_E_SUCCESS) \ | |
385 | { \ | |
386 | DEBUG(D_tls) debug_printf("TLS: cert problem: %s: %s\n", \ | |
387 | (Label), gnutls_strerror(rc)); \ | |
388 | return rc; \ | |
389 | } \ | |
390 | } while (0) | |
9d1c15ef JH |
391 | |
392 | static int | |
27f19eb4 | 393 | import_cert(const gnutls_datum_t * cert, gnutls_x509_crt_t * crtp) |
9d1c15ef JH |
394 | { |
395 | int rc; | |
396 | ||
397 | rc = gnutls_x509_crt_init(crtp); | |
398 | exim_gnutls_cert_err(US"gnutls_x509_crt_init (crt)"); | |
399 | ||
400 | rc = gnutls_x509_crt_import(*crtp, cert, GNUTLS_X509_FMT_DER); | |
401 | exim_gnutls_cert_err(US"failed to import certificate [gnutls_x509_crt_import(cert)]"); | |
402 | ||
403 | return rc; | |
404 | } | |
405 | ||
406 | #undef exim_gnutls_cert_err | |
407 | ||
408 | ||
17c76198 PP |
409 | /* We set various Exim global variables from the state, once a session has |
410 | been established. With TLS callouts, may need to change this to stack | |
411 | variables, or just re-call it with the server state after client callout | |
412 | has finished. | |
059ec3d9 | 413 | |
9d1c15ef | 414 | Make sure anything set here is unset in tls_getc(). |
17c76198 PP |
415 | |
416 | Sets: | |
417 | tls_active fd | |
418 | tls_bits strength indicator | |
419 | tls_certificate_verified bool indicator | |
420 | tls_channelbinding_b64 for some SASL mechanisms | |
421 | tls_cipher a string | |
9d1c15ef | 422 | tls_peercert pointer to library internal |
17c76198 PP |
423 | tls_peerdn a string |
424 | tls_sni a (UTF-8) string | |
9d1c15ef | 425 | tls_ourcert pointer to library internal |
17c76198 PP |
426 | |
427 | Argument: | |
428 | state the relevant exim_gnutls_state_st * | |
429 | */ | |
430 | ||
431 | static void | |
9d1c15ef | 432 | extract_exim_vars_from_tls_state(exim_gnutls_state_st * state) |
17c76198 | 433 | { |
17c76198 | 434 | gnutls_cipher_algorithm_t cipher; |
17c76198 PP |
435 | #ifdef HAVE_GNUTLS_SESSION_CHANNEL_BINDING |
436 | int old_pool; | |
437 | int rc; | |
438 | gnutls_datum_t channel; | |
439 | #endif | |
9d1c15ef | 440 | tls_support * tlsp = state->tlsp; |
17c76198 | 441 | |
9d1c15ef | 442 | tlsp->active = state->fd_out; |
17c76198 PP |
443 | |
444 | cipher = gnutls_cipher_get(state->session); | |
445 | /* returns size in "bytes" */ | |
9d1c15ef | 446 | tlsp->bits = gnutls_cipher_get_key_size(cipher) * 8; |
17c76198 | 447 | |
9d1c15ef | 448 | tlsp->cipher = state->ciphersuite; |
17c76198 | 449 | |
817d9f57 | 450 | DEBUG(D_tls) debug_printf("cipher: %s\n", state->ciphersuite); |
17c76198 | 451 | |
9d1c15ef | 452 | tlsp->certificate_verified = state->peer_cert_verified; |
899b8bbc JH |
453 | #ifdef SUPPORT_DANE |
454 | tlsp->dane_verified = state->peer_dane_verified; | |
455 | #endif | |
059ec3d9 | 456 | |
17c76198 PP |
457 | /* note that tls_channelbinding_b64 is not saved to the spool file, since it's |
458 | only available for use for authenticators while this TLS session is running. */ | |
459 | ||
460 | tls_channelbinding_b64 = NULL; | |
461 | #ifdef HAVE_GNUTLS_SESSION_CHANNEL_BINDING | |
462 | channel.data = NULL; | |
463 | channel.size = 0; | |
464 | rc = gnutls_session_channel_binding(state->session, GNUTLS_CB_TLS_UNIQUE, &channel); | |
465 | if (rc) { | |
466 | DEBUG(D_tls) debug_printf("Channel binding error: %s\n", gnutls_strerror(rc)); | |
467 | } else { | |
468 | old_pool = store_pool; | |
469 | store_pool = POOL_PERM; | |
f4d091fb | 470 | tls_channelbinding_b64 = b64encode(channel.data, (int)channel.size); |
17c76198 PP |
471 | store_pool = old_pool; |
472 | DEBUG(D_tls) debug_printf("Have channel bindings cached for possible auth usage.\n"); | |
473 | } | |
474 | #endif | |
475 | ||
9d1c15ef JH |
476 | /* peercert is set in peer_status() */ |
477 | tlsp->peerdn = state->peerdn; | |
478 | tlsp->sni = state->received_sni; | |
479 | ||
480 | /* record our certificate */ | |
481 | { | |
27f19eb4 | 482 | const gnutls_datum_t * cert = gnutls_certificate_get_ours(state->session); |
9d1c15ef JH |
483 | gnutls_x509_crt_t crt; |
484 | ||
485 | tlsp->ourcert = cert && import_cert(cert, &crt)==0 ? crt : NULL; | |
486 | } | |
059ec3d9 PH |
487 | } |
488 | ||
489 | ||
490 | ||
17c76198 | 491 | |
059ec3d9 | 492 | /************************************************* |
575643cd | 493 | * Setup up DH parameters * |
059ec3d9 PH |
494 | *************************************************/ |
495 | ||
575643cd | 496 | /* Generating the D-H parameters may take a long time. They only need to |
059ec3d9 PH |
497 | be re-generated every so often, depending on security policy. What we do is to |
498 | keep these parameters in a file in the spool directory. If the file does not | |
499 | exist, we generate them. This means that it is easy to cause a regeneration. | |
500 | ||
501 | The new file is written as a temporary file and renamed, so that an incomplete | |
502 | file is never present. If two processes both compute some new parameters, you | |
503 | waste a bit of effort, but it doesn't seem worth messing around with locking to | |
504 | prevent this. | |
505 | ||
059ec3d9 PH |
506 | Returns: OK/DEFER/FAIL |
507 | */ | |
508 | ||
509 | static int | |
cf0c6164 | 510 | init_server_dh(uschar ** errstr) |
059ec3d9 | 511 | { |
17c76198 PP |
512 | int fd, rc; |
513 | unsigned int dh_bits; | |
27f19eb4 | 514 | gnutls_datum_t m; |
a799883d PP |
515 | uschar filename_buf[PATH_MAX]; |
516 | uschar *filename = NULL; | |
17c76198 | 517 | size_t sz; |
a799883d PP |
518 | uschar *exp_tls_dhparam; |
519 | BOOL use_file_in_spool = FALSE; | |
520 | BOOL use_fixed_file = FALSE; | |
17c76198 | 521 | host_item *host = NULL; /* dummy for macros */ |
059ec3d9 | 522 | |
17c76198 | 523 | DEBUG(D_tls) debug_printf("Initialising GnuTLS server params.\n"); |
059ec3d9 | 524 | |
17c76198 | 525 | rc = gnutls_dh_params_init(&dh_server_params); |
47195144 | 526 | exim_gnutls_err_check(rc, US"gnutls_dh_params_init"); |
059ec3d9 | 527 | |
a799883d PP |
528 | m.data = NULL; |
529 | m.size = 0; | |
530 | ||
cf0c6164 | 531 | if (!expand_check(tls_dhparam, US"tls_dhparam", &exp_tls_dhparam, errstr)) |
a799883d PP |
532 | return DEFER; |
533 | ||
534 | if (!exp_tls_dhparam) | |
535 | { | |
536 | DEBUG(D_tls) debug_printf("Loading default hard-coded DH params\n"); | |
537 | m.data = US std_dh_prime_default(); | |
538 | m.size = Ustrlen(m.data); | |
539 | } | |
540 | else if (Ustrcmp(exp_tls_dhparam, "historic") == 0) | |
541 | use_file_in_spool = TRUE; | |
542 | else if (Ustrcmp(exp_tls_dhparam, "none") == 0) | |
543 | { | |
544 | DEBUG(D_tls) debug_printf("Requested no DH parameters.\n"); | |
545 | return OK; | |
546 | } | |
547 | else if (exp_tls_dhparam[0] != '/') | |
548 | { | |
f5d25c2b | 549 | if (!(m.data = US std_dh_prime_named(exp_tls_dhparam))) |
cf0c6164 | 550 | return tls_error(US"No standard prime named", CS exp_tls_dhparam, NULL, errstr); |
a799883d PP |
551 | m.size = Ustrlen(m.data); |
552 | } | |
553 | else | |
554 | { | |
555 | use_fixed_file = TRUE; | |
556 | filename = exp_tls_dhparam; | |
557 | } | |
558 | ||
559 | if (m.data) | |
560 | { | |
561 | rc = gnutls_dh_params_import_pkcs3(dh_server_params, &m, GNUTLS_X509_FMT_PEM); | |
47195144 | 562 | exim_gnutls_err_check(rc, US"gnutls_dh_params_import_pkcs3"); |
a799883d PP |
563 | DEBUG(D_tls) debug_printf("Loaded fixed standard D-H parameters\n"); |
564 | return OK; | |
565 | } | |
566 | ||
af3498d6 PP |
567 | #ifdef HAVE_GNUTLS_SEC_PARAM_CONSTANTS |
568 | /* If you change this constant, also change dh_param_fn_ext so that we can use a | |
17c76198 PP |
569 | different filename and ensure we have sufficient bits. */ |
570 | dh_bits = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, GNUTLS_SEC_PARAM_NORMAL); | |
571 | if (!dh_bits) | |
cf0c6164 | 572 | return tls_error(US"gnutls_sec_param_to_pk_bits() failed", NULL, NULL, errstr); |
af3498d6 | 573 | DEBUG(D_tls) |
b34fc30c | 574 | debug_printf("GnuTLS tells us that for D-H PK, NORMAL is %d bits.\n", |
af3498d6 PP |
575 | dh_bits); |
576 | #else | |
577 | dh_bits = EXIM_SERVER_DH_BITS_PRE2_12; | |
578 | DEBUG(D_tls) | |
579 | debug_printf("GnuTLS lacks gnutls_sec_param_to_pk_bits(), using %d bits.\n", | |
580 | dh_bits); | |
581 | #endif | |
059ec3d9 | 582 | |
3375e053 PP |
583 | /* Some clients have hard-coded limits. */ |
584 | if (dh_bits > tls_dh_max_bits) | |
585 | { | |
586 | DEBUG(D_tls) | |
587 | debug_printf("tls_dh_max_bits clamping override, using %d bits instead.\n", | |
588 | tls_dh_max_bits); | |
589 | dh_bits = tls_dh_max_bits; | |
590 | } | |
591 | ||
a799883d PP |
592 | if (use_file_in_spool) |
593 | { | |
594 | if (!string_format(filename_buf, sizeof(filename_buf), | |
595 | "%s/gnutls-params-%d", spool_directory, dh_bits)) | |
cf0c6164 | 596 | return tls_error(US"overlong filename", NULL, NULL, errstr); |
a799883d PP |
597 | filename = filename_buf; |
598 | } | |
059ec3d9 | 599 | |
b5aea5e1 | 600 | /* Open the cache file for reading and if successful, read it and set up the |
575643cd | 601 | parameters. */ |
059ec3d9 | 602 | |
f5d25c2b | 603 | if ((fd = Uopen(filename, O_RDONLY, 0)) >= 0) |
059ec3d9 | 604 | { |
b5aea5e1 | 605 | struct stat statbuf; |
17c76198 PP |
606 | FILE *fp; |
607 | int saved_errno; | |
608 | ||
609 | if (fstat(fd, &statbuf) < 0) /* EIO */ | |
610 | { | |
611 | saved_errno = errno; | |
612 | (void)close(fd); | |
cf0c6164 | 613 | return tls_error(US"TLS cache stat failed", strerror(saved_errno), NULL, errstr); |
17c76198 PP |
614 | } |
615 | if (!S_ISREG(statbuf.st_mode)) | |
b5aea5e1 PH |
616 | { |
617 | (void)close(fd); | |
cf0c6164 | 618 | return tls_error(US"TLS cache not a file", NULL, NULL, errstr); |
17c76198 | 619 | } |
40c90bca | 620 | if (!(fp = fdopen(fd, "rb"))) |
17c76198 PP |
621 | { |
622 | saved_errno = errno; | |
623 | (void)close(fd); | |
624 | return tls_error(US"fdopen(TLS cache stat fd) failed", | |
cf0c6164 | 625 | strerror(saved_errno), NULL, errstr); |
b5aea5e1 | 626 | } |
059ec3d9 | 627 | |
b5aea5e1 | 628 | m.size = statbuf.st_size; |
40c90bca | 629 | if (!(m.data = malloc(m.size))) |
17c76198 PP |
630 | { |
631 | fclose(fp); | |
cf0c6164 | 632 | return tls_error(US"malloc failed", strerror(errno), NULL, errstr); |
17c76198 | 633 | } |
40c90bca | 634 | if (!(sz = fread(m.data, m.size, 1, fp))) |
17c76198 PP |
635 | { |
636 | saved_errno = errno; | |
637 | fclose(fp); | |
638 | free(m.data); | |
cf0c6164 | 639 | return tls_error(US"fread failed", strerror(saved_errno), NULL, errstr); |
17c76198 PP |
640 | } |
641 | fclose(fp); | |
b5aea5e1 | 642 | |
17c76198 | 643 | rc = gnutls_dh_params_import_pkcs3(dh_server_params, &m, GNUTLS_X509_FMT_PEM); |
b5aea5e1 | 644 | free(m.data); |
47195144 | 645 | exim_gnutls_err_check(rc, US"gnutls_dh_params_import_pkcs3"); |
17c76198 | 646 | DEBUG(D_tls) debug_printf("read D-H parameters from file \"%s\"\n", filename); |
b5aea5e1 PH |
647 | } |
648 | ||
649 | /* If the file does not exist, fall through to compute new data and cache it. | |
650 | If there was any other opening error, it is serious. */ | |
651 | ||
182ad5cf PH |
652 | else if (errno == ENOENT) |
653 | { | |
17c76198 | 654 | rc = -1; |
182ad5cf | 655 | DEBUG(D_tls) |
17c76198 | 656 | debug_printf("D-H parameter cache file \"%s\" does not exist\n", filename); |
182ad5cf PH |
657 | } |
658 | else | |
17c76198 | 659 | return tls_error(string_open_failed(errno, "\"%s\" for reading", filename), |
cf0c6164 | 660 | NULL, NULL, errstr); |
b5aea5e1 PH |
661 | |
662 | /* If ret < 0, either the cache file does not exist, or the data it contains | |
663 | is not useful. One particular case of this is when upgrading from an older | |
664 | release of Exim in which the data was stored in a different format. We don't | |
665 | try to be clever and support both formats; we just regenerate new data in this | |
666 | case. */ | |
667 | ||
17c76198 | 668 | if (rc < 0) |
b5aea5e1 | 669 | { |
17c76198 | 670 | uschar *temp_fn; |
201f5254 | 671 | unsigned int dh_bits_gen = dh_bits; |
059ec3d9 | 672 | |
17c76198 PP |
673 | if ((PATH_MAX - Ustrlen(filename)) < 10) |
674 | return tls_error(US"Filename too long to generate replacement", | |
cf0c6164 | 675 | CS filename, NULL, errstr); |
059ec3d9 | 676 | |
17c76198 | 677 | temp_fn = string_copy(US "%s.XXXXXXX"); |
f5d25c2b | 678 | if ((fd = mkstemp(CS temp_fn)) < 0) /* modifies temp_fn */ |
cf0c6164 | 679 | return tls_error(US"Unable to open temp file", strerror(errno), NULL, errstr); |
059ec3d9 PH |
680 | (void)fchown(fd, exim_uid, exim_gid); /* Probably not necessary */ |
681 | ||
201f5254 PP |
682 | /* GnuTLS overshoots! |
683 | * If we ask for 2236, we might get 2237 or more. | |
684 | * But there's no way to ask GnuTLS how many bits there really are. | |
685 | * We can ask how many bits were used in a TLS session, but that's it! | |
686 | * The prime itself is hidden behind too much abstraction. | |
687 | * So we ask for less, and proceed on a wing and a prayer. | |
688 | * First attempt, subtracted 3 for 2233 and got 2240. | |
689 | */ | |
cae6e576 | 690 | if (dh_bits >= EXIM_CLIENT_DH_MIN_BITS + 10) |
201f5254 PP |
691 | { |
692 | dh_bits_gen = dh_bits - 10; | |
693 | DEBUG(D_tls) | |
694 | debug_printf("being paranoid about DH generation, make it '%d' bits'\n", | |
695 | dh_bits_gen); | |
696 | } | |
697 | ||
698 | DEBUG(D_tls) | |
699 | debug_printf("requesting generation of %d bit Diffie-Hellman prime ...\n", | |
700 | dh_bits_gen); | |
701 | rc = gnutls_dh_params_generate2(dh_server_params, dh_bits_gen); | |
47195144 | 702 | exim_gnutls_err_check(rc, US"gnutls_dh_params_generate2"); |
17c76198 PP |
703 | |
704 | /* gnutls_dh_params_export_pkcs3() will tell us the exact size, every time, | |
705 | and I confirmed that a NULL call to get the size first is how the GnuTLS | |
706 | sample apps handle this. */ | |
707 | ||
708 | sz = 0; | |
709 | m.data = NULL; | |
710 | rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM, | |
711 | m.data, &sz); | |
712 | if (rc != GNUTLS_E_SHORT_MEMORY_BUFFER) | |
47195144 | 713 | exim_gnutls_err_check(rc, US"gnutls_dh_params_export_pkcs3(NULL) sizing"); |
17c76198 | 714 | m.size = sz; |
40c90bca | 715 | if (!(m.data = malloc(m.size))) |
cf0c6164 | 716 | return tls_error(US"memory allocation failed", strerror(errno), NULL, errstr); |
40c90bca | 717 | |
1f00591e | 718 | /* this will return a size 1 less than the allocation size above */ |
17c76198 | 719 | rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM, |
1f00591e | 720 | m.data, &sz); |
17c76198 PP |
721 | if (rc != GNUTLS_E_SUCCESS) |
722 | { | |
723 | free(m.data); | |
47195144 | 724 | exim_gnutls_err_check(rc, US"gnutls_dh_params_export_pkcs3() real"); |
17c76198 | 725 | } |
1f00591e | 726 | m.size = sz; /* shrink by 1, probably */ |
059ec3d9 | 727 | |
f5d25c2b | 728 | if ((sz = write_to_fd_buf(fd, m.data, (size_t) m.size)) != m.size) |
17c76198 PP |
729 | { |
730 | free(m.data); | |
731 | return tls_error(US"TLS cache write D-H params failed", | |
cf0c6164 | 732 | strerror(errno), NULL, errstr); |
17c76198 | 733 | } |
b5aea5e1 | 734 | free(m.data); |
f5d25c2b | 735 | if ((sz = write_to_fd_buf(fd, US"\n", 1)) != 1) |
17c76198 | 736 | return tls_error(US"TLS cache write D-H params final newline failed", |
cf0c6164 | 737 | strerror(errno), NULL, errstr); |
17c76198 | 738 | |
f5d25c2b | 739 | if ((rc = close(fd))) |
cf0c6164 | 740 | return tls_error(US"TLS cache write close() failed", strerror(errno), NULL, errstr); |
059ec3d9 | 741 | |
17c76198 PP |
742 | if (Urename(temp_fn, filename) < 0) |
743 | return tls_error(string_sprintf("failed to rename \"%s\" as \"%s\"", | |
cf0c6164 | 744 | temp_fn, filename), strerror(errno), NULL, errstr); |
059ec3d9 | 745 | |
17c76198 | 746 | DEBUG(D_tls) debug_printf("wrote D-H parameters to file \"%s\"\n", filename); |
059ec3d9 PH |
747 | } |
748 | ||
17c76198 | 749 | DEBUG(D_tls) debug_printf("initialized server D-H parameters\n"); |
059ec3d9 PH |
750 | return OK; |
751 | } | |
752 | ||
753 | ||
754 | ||
755 | ||
23bb6982 JH |
756 | /* Create and install a selfsigned certificate, for use in server mode */ |
757 | ||
758 | static int | |
cf0c6164 | 759 | tls_install_selfsign(exim_gnutls_state_st * state, uschar ** errstr) |
23bb6982 JH |
760 | { |
761 | gnutls_x509_crt_t cert = NULL; | |
762 | time_t now; | |
763 | gnutls_x509_privkey_t pkey = NULL; | |
764 | const uschar * where; | |
765 | int rc; | |
766 | ||
767 | where = US"initialising pkey"; | |
768 | if ((rc = gnutls_x509_privkey_init(&pkey))) goto err; | |
769 | ||
770 | where = US"initialising cert"; | |
771 | if ((rc = gnutls_x509_crt_init(&cert))) goto err; | |
772 | ||
773 | where = US"generating pkey"; | |
774 | if ((rc = gnutls_x509_privkey_generate(pkey, GNUTLS_PK_RSA, | |
76075bb5 | 775 | #ifdef SUPPORT_PARAM_TO_PK_BITS |
23bb6982 | 776 | gnutls_sec_param_to_pk_bits(GNUTLS_PK_RSA, GNUTLS_SEC_PARAM_LOW), |
76075bb5 JH |
777 | #else |
778 | 1024, | |
779 | #endif | |
780 | 0))) | |
23bb6982 JH |
781 | goto err; |
782 | ||
783 | where = US"configuring cert"; | |
784 | now = 0; | |
785 | if ( (rc = gnutls_x509_crt_set_version(cert, 3)) | |
786 | || (rc = gnutls_x509_crt_set_serial(cert, &now, sizeof(now))) | |
787 | || (rc = gnutls_x509_crt_set_activation_time(cert, now = time(NULL))) | |
788 | || (rc = gnutls_x509_crt_set_expiration_time(cert, now + 60 * 60)) /* 1 hr */ | |
789 | || (rc = gnutls_x509_crt_set_key(cert, pkey)) | |
790 | ||
791 | || (rc = gnutls_x509_crt_set_dn_by_oid(cert, | |
792 | GNUTLS_OID_X520_COUNTRY_NAME, 0, "UK", 2)) | |
793 | || (rc = gnutls_x509_crt_set_dn_by_oid(cert, | |
794 | GNUTLS_OID_X520_ORGANIZATION_NAME, 0, "Exim Developers", 15)) | |
795 | || (rc = gnutls_x509_crt_set_dn_by_oid(cert, | |
796 | GNUTLS_OID_X520_COMMON_NAME, 0, | |
797 | smtp_active_hostname, Ustrlen(smtp_active_hostname))) | |
798 | ) | |
799 | goto err; | |
800 | ||
801 | where = US"signing cert"; | |
802 | if ((rc = gnutls_x509_crt_sign(cert, cert, pkey))) goto err; | |
803 | ||
804 | where = US"installing selfsign cert"; | |
805 | /* Since: 2.4.0 */ | |
806 | if ((rc = gnutls_certificate_set_x509_key(state->x509_cred, &cert, 1, pkey))) | |
807 | goto err; | |
808 | ||
809 | rc = OK; | |
810 | ||
811 | out: | |
812 | if (cert) gnutls_x509_crt_deinit(cert); | |
813 | if (pkey) gnutls_x509_privkey_deinit(pkey); | |
814 | return rc; | |
815 | ||
816 | err: | |
cf0c6164 | 817 | rc = tls_error(where, gnutls_strerror(rc), NULL, errstr); |
23bb6982 JH |
818 | goto out; |
819 | } | |
820 | ||
821 | ||
822 | ||
823 | ||
47195144 JH |
824 | /* Add certificate and key, from files. |
825 | ||
826 | Return: | |
827 | Zero or negative: good. Negate value for certificate index if < 0. | |
828 | Greater than zero: FAIL or DEFER code. | |
829 | */ | |
830 | ||
ba86e143 JH |
831 | static int |
832 | tls_add_certfile(exim_gnutls_state_st * state, const host_item * host, | |
833 | uschar * certfile, uschar * keyfile, uschar ** errstr) | |
834 | { | |
835 | int rc = gnutls_certificate_set_x509_key_file(state->x509_cred, | |
836 | CS certfile, CS keyfile, GNUTLS_X509_FMT_PEM); | |
47195144 JH |
837 | if (rc < 0) |
838 | return tls_error( | |
839 | string_sprintf("cert/key setup: cert=%s key=%s", certfile, keyfile), | |
840 | gnutls_strerror(rc), host, errstr); | |
841 | return -rc; | |
ba86e143 JH |
842 | } |
843 | ||
844 | ||
059ec3d9 | 845 | /************************************************* |
17c76198 | 846 | * Variables re-expanded post-SNI * |
059ec3d9 PH |
847 | *************************************************/ |
848 | ||
17c76198 PP |
849 | /* Called from both server and client code, via tls_init(), and also from |
850 | the SNI callback after receiving an SNI, if tls_certificate includes "tls_sni". | |
851 | ||
852 | We can tell the two apart by state->received_sni being non-NULL in callback. | |
853 | ||
854 | The callback should not call us unless state->trigger_sni_changes is true, | |
855 | which we are responsible for setting on the first pass through. | |
059ec3d9 PH |
856 | |
857 | Arguments: | |
17c76198 | 858 | state exim_gnutls_state_st * |
cf0c6164 | 859 | errstr error string pointer |
059ec3d9 PH |
860 | |
861 | Returns: OK/DEFER/FAIL | |
862 | */ | |
863 | ||
864 | static int | |
ba86e143 | 865 | tls_expand_session_files(exim_gnutls_state_st * state, uschar ** errstr) |
059ec3d9 | 866 | { |
1365611d | 867 | struct stat statbuf; |
059ec3d9 | 868 | int rc; |
17c76198 PP |
869 | const host_item *host = state->host; /* macro should be reconsidered? */ |
870 | uschar *saved_tls_certificate = NULL; | |
871 | uschar *saved_tls_privatekey = NULL; | |
872 | uschar *saved_tls_verify_certificates = NULL; | |
873 | uschar *saved_tls_crl = NULL; | |
874 | int cert_count; | |
875 | ||
876 | /* We check for tls_sni *before* expansion. */ | |
2b4a568d | 877 | if (!host) /* server */ |
17c76198 PP |
878 | if (!state->received_sni) |
879 | { | |
ba86e143 JH |
880 | if ( state->tls_certificate |
881 | && ( Ustrstr(state->tls_certificate, US"tls_sni") | |
882 | || Ustrstr(state->tls_certificate, US"tls_in_sni") | |
883 | || Ustrstr(state->tls_certificate, US"tls_out_sni") | |
884 | ) ) | |
17c76198 PP |
885 | { |
886 | DEBUG(D_tls) debug_printf("We will re-expand TLS session files if we receive SNI.\n"); | |
887 | state->trigger_sni_changes = TRUE; | |
888 | } | |
889 | } | |
890 | else | |
891 | { | |
1365611d | 892 | /* useful for debugging */ |
17c76198 PP |
893 | saved_tls_certificate = state->exp_tls_certificate; |
894 | saved_tls_privatekey = state->exp_tls_privatekey; | |
895 | saved_tls_verify_certificates = state->exp_tls_verify_certificates; | |
896 | saved_tls_crl = state->exp_tls_crl; | |
897 | } | |
059ec3d9 | 898 | |
1365611d | 899 | rc = gnutls_certificate_allocate_credentials(&state->x509_cred); |
47195144 JH |
900 | exim_gnutls_err_check(rc, US"gnutls_certificate_allocate_credentials"); |
901 | ||
902 | #ifdef SUPPORT_SRV_OCSP_STACK | |
903 | gnutls_certificate_set_flags(state->x509_cred, GNUTLS_CERTIFICATE_API_V2); | |
904 | #endif | |
1365611d | 905 | |
17c76198 PP |
906 | /* remember: expand_check_tlsvar() is expand_check() but fiddling with |
907 | state members, assuming consistent naming; and expand_check() returns | |
908 | false if expansion failed, unless expansion was forced to fail. */ | |
059ec3d9 | 909 | |
17c76198 PP |
910 | /* check if we at least have a certificate, before doing expensive |
911 | D-H generation. */ | |
059ec3d9 | 912 | |
cf0c6164 | 913 | if (!expand_check_tlsvar(tls_certificate, errstr)) |
17c76198 | 914 | return DEFER; |
059ec3d9 | 915 | |
17c76198 | 916 | /* certificate is mandatory in server, optional in client */ |
059ec3d9 | 917 | |
23bb6982 JH |
918 | if ( !state->exp_tls_certificate |
919 | || !*state->exp_tls_certificate | |
920 | ) | |
2b4a568d | 921 | if (!host) |
cf0c6164 | 922 | return tls_install_selfsign(state, errstr); |
17c76198 PP |
923 | else |
924 | DEBUG(D_tls) debug_printf("TLS: no client certificate specified; okay\n"); | |
059ec3d9 | 925 | |
cf0c6164 | 926 | if (state->tls_privatekey && !expand_check_tlsvar(tls_privatekey, errstr)) |
059ec3d9 PH |
927 | return DEFER; |
928 | ||
17c76198 PP |
929 | /* tls_privatekey is optional, defaulting to same file as certificate */ |
930 | ||
931 | if (state->tls_privatekey == NULL || *state->tls_privatekey == '\0') | |
059ec3d9 | 932 | { |
17c76198 PP |
933 | state->tls_privatekey = state->tls_certificate; |
934 | state->exp_tls_privatekey = state->exp_tls_certificate; | |
059ec3d9 | 935 | } |
c91535f3 | 936 | |
059ec3d9 | 937 | |
17c76198 | 938 | if (state->exp_tls_certificate && *state->exp_tls_certificate) |
059ec3d9 PH |
939 | { |
940 | DEBUG(D_tls) debug_printf("certificate file = %s\nkey file = %s\n", | |
17c76198 PP |
941 | state->exp_tls_certificate, state->exp_tls_privatekey); |
942 | ||
943 | if (state->received_sni) | |
23bb6982 JH |
944 | if ( Ustrcmp(state->exp_tls_certificate, saved_tls_certificate) == 0 |
945 | && Ustrcmp(state->exp_tls_privatekey, saved_tls_privatekey) == 0 | |
946 | ) | |
17c76198 | 947 | { |
b34fc30c | 948 | DEBUG(D_tls) debug_printf("TLS SNI: cert and key unchanged\n"); |
17c76198 PP |
949 | } |
950 | else | |
951 | { | |
b34fc30c | 952 | DEBUG(D_tls) debug_printf("TLS SNI: have a changed cert/key pair.\n"); |
17c76198 | 953 | } |
059ec3d9 | 954 | |
ba86e143 JH |
955 | if (!host) /* server */ |
956 | { | |
957 | const uschar * clist = state->exp_tls_certificate; | |
958 | const uschar * klist = state->exp_tls_privatekey; | |
47195144 JH |
959 | const uschar * olist; |
960 | int csep = 0, ksep = 0, osep = 0, cnt = 0; | |
961 | uschar * cfile, * kfile, * ofile; | |
962 | ||
963 | #ifndef DISABLE_OCSP | |
964 | if (!expand_check(tls_ocsp_file, US"tls_ocsp_file", &ofile, errstr)) | |
965 | return DEFER; | |
966 | olist = ofile; | |
967 | #endif | |
ba86e143 JH |
968 | |
969 | while (cfile = string_nextinlist(&clist, &csep, NULL, 0)) | |
47195144 | 970 | |
ba86e143 JH |
971 | if (!(kfile = string_nextinlist(&klist, &ksep, NULL, 0))) |
972 | return tls_error(US"cert/key setup: out of keys", NULL, host, errstr); | |
47195144 | 973 | else if (0 < (rc = tls_add_certfile(state, host, cfile, kfile, errstr))) |
ba86e143 JH |
974 | return rc; |
975 | else | |
47195144 JH |
976 | { |
977 | int gnutls_cert_index = -rc; | |
ba86e143 | 978 | DEBUG(D_tls) debug_printf("TLS: cert/key %s registered\n", cfile); |
47195144 JH |
979 | |
980 | /* Set the OCSP stapling server info */ | |
981 | ||
982 | #ifndef DISABLE_OCSP | |
983 | if (tls_ocsp_file) | |
984 | if (gnutls_buggy_ocsp) | |
985 | { | |
986 | DEBUG(D_tls) | |
987 | debug_printf("GnuTLS library is buggy for OCSP; avoiding\n"); | |
988 | } | |
989 | else if ((ofile = string_nextinlist(&olist, &osep, NULL, 0))) | |
990 | { | |
991 | /* Use the full callback method for stapling just to get | |
992 | observability. More efficient would be to read the file once only, | |
993 | if it never changed (due to SNI). Would need restart on file update, | |
994 | or watch datestamp. */ | |
995 | ||
996 | # ifdef SUPPORT_SRV_OCSP_STACK | |
997 | rc = gnutls_certificate_set_ocsp_status_request_function2( | |
998 | state->x509_cred, gnutls_cert_index, | |
999 | server_ocsp_stapling_cb, ofile); | |
1000 | ||
1001 | exim_gnutls_err_check(rc, | |
1002 | US"gnutls_certificate_set_ocsp_status_request_function2"); | |
1003 | # else | |
1004 | if (cnt++ > 0) | |
1005 | { | |
1006 | DEBUG(D_tls) | |
1007 | debug_printf("oops; multiple OCSP files not supported\n"); | |
1008 | break; | |
1009 | } | |
1010 | gnutls_certificate_set_ocsp_status_request_function( | |
1011 | state->x509_cred, server_ocsp_stapling_cb, ofile); | |
1012 | # endif | |
1013 | ||
1014 | DEBUG(D_tls) debug_printf("OCSP response file = %s\n", ofile); | |
1015 | } | |
1016 | else | |
1017 | DEBUG(D_tls) debug_printf("ran out of OCSP response files in list\n"); | |
1018 | #endif | |
1019 | } | |
ba86e143 JH |
1020 | } |
1021 | else | |
1022 | { | |
47195144 | 1023 | if (0 < (rc = tls_add_certfile(state, host, |
ba86e143 JH |
1024 | state->exp_tls_certificate, state->exp_tls_privatekey, errstr))) |
1025 | return rc; | |
1026 | DEBUG(D_tls) debug_printf("TLS: cert/key registered\n"); | |
1027 | } | |
1028 | ||
b34fc30c | 1029 | } /* tls_certificate */ |
059ec3d9 | 1030 | |
2b4a568d | 1031 | |
059ec3d9 PH |
1032 | /* Set the trusted CAs file if one is provided, and then add the CRL if one is |
1033 | provided. Experiment shows that, if the certificate file is empty, an unhelpful | |
1034 | error message is provided. However, if we just refrain from setting anything up | |
1035 | in that case, certificate verification fails, which seems to be the correct | |
1036 | behaviour. */ | |
1037 | ||
610ff438 | 1038 | if (state->tls_verify_certificates && *state->tls_verify_certificates) |
059ec3d9 | 1039 | { |
cf0c6164 | 1040 | if (!expand_check_tlsvar(tls_verify_certificates, errstr)) |
059ec3d9 | 1041 | return DEFER; |
610ff438 JH |
1042 | #ifndef SUPPORT_SYSDEFAULT_CABUNDLE |
1043 | if (Ustrcmp(state->exp_tls_verify_certificates, "system") == 0) | |
1044 | state->exp_tls_verify_certificates = NULL; | |
1045 | #endif | |
17c76198 | 1046 | if (state->tls_crl && *state->tls_crl) |
cf0c6164 | 1047 | if (!expand_check_tlsvar(tls_crl, errstr)) |
17c76198 | 1048 | return DEFER; |
059ec3d9 | 1049 | |
1365611d PP |
1050 | if (!(state->exp_tls_verify_certificates && |
1051 | *state->exp_tls_verify_certificates)) | |
b34fc30c PP |
1052 | { |
1053 | DEBUG(D_tls) | |
1365611d PP |
1054 | debug_printf("TLS: tls_verify_certificates expanded empty, ignoring\n"); |
1055 | /* With no tls_verify_certificates, we ignore tls_crl too */ | |
17c76198 | 1056 | return OK; |
b34fc30c | 1057 | } |
1365611d | 1058 | } |
83e2f8a2 PP |
1059 | else |
1060 | { | |
1061 | DEBUG(D_tls) | |
1062 | debug_printf("TLS: tls_verify_certificates not set or empty, ignoring\n"); | |
1063 | return OK; | |
1064 | } | |
17c76198 | 1065 | |
cb1d7830 JH |
1066 | #ifdef SUPPORT_SYSDEFAULT_CABUNDLE |
1067 | if (Ustrcmp(state->exp_tls_verify_certificates, "system") == 0) | |
1068 | cert_count = gnutls_certificate_set_x509_system_trust(state->x509_cred); | |
1069 | else | |
1070 | #endif | |
1365611d | 1071 | { |
cb1d7830 JH |
1072 | if (Ustat(state->exp_tls_verify_certificates, &statbuf) < 0) |
1073 | { | |
1074 | log_write(0, LOG_MAIN|LOG_PANIC, "could not stat %s " | |
1075 | "(tls_verify_certificates): %s", state->exp_tls_verify_certificates, | |
1076 | strerror(errno)); | |
1077 | return DEFER; | |
1078 | } | |
17c76198 | 1079 | |
a7fec7a7 | 1080 | #ifndef SUPPORT_CA_DIR |
cb1d7830 JH |
1081 | /* The test suite passes in /dev/null; we could check for that path explicitly, |
1082 | but who knows if someone has some weird FIFO which always dumps some certs, or | |
1083 | other weirdness. The thing we really want to check is that it's not a | |
1084 | directory, since while OpenSSL supports that, GnuTLS does not. | |
60f914bc | 1085 | So s/!S_ISREG/S_ISDIR/ and change some messaging ... */ |
cb1d7830 JH |
1086 | if (S_ISDIR(statbuf.st_mode)) |
1087 | { | |
1088 | DEBUG(D_tls) | |
1089 | debug_printf("verify certificates path is a dir: \"%s\"\n", | |
1090 | state->exp_tls_verify_certificates); | |
1091 | log_write(0, LOG_MAIN|LOG_PANIC, | |
1092 | "tls_verify_certificates \"%s\" is a directory", | |
1093 | state->exp_tls_verify_certificates); | |
1094 | return DEFER; | |
1095 | } | |
a7fec7a7 | 1096 | #endif |
059ec3d9 | 1097 | |
cb1d7830 JH |
1098 | DEBUG(D_tls) debug_printf("verify certificates = %s size=" OFF_T_FMT "\n", |
1099 | state->exp_tls_verify_certificates, statbuf.st_size); | |
059ec3d9 | 1100 | |
cb1d7830 JH |
1101 | if (statbuf.st_size == 0) |
1102 | { | |
1103 | DEBUG(D_tls) | |
1104 | debug_printf("cert file empty, no certs, no verification, ignoring any CRL\n"); | |
1105 | return OK; | |
1106 | } | |
059ec3d9 | 1107 | |
cb1d7830 | 1108 | cert_count = |
a7fec7a7 JH |
1109 | |
1110 | #ifdef SUPPORT_CA_DIR | |
cb1d7830 JH |
1111 | (statbuf.st_mode & S_IFMT) == S_IFDIR |
1112 | ? | |
1113 | gnutls_certificate_set_x509_trust_dir(state->x509_cred, | |
1114 | CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM) | |
1115 | : | |
a7fec7a7 | 1116 | #endif |
cb1d7830 JH |
1117 | gnutls_certificate_set_x509_trust_file(state->x509_cred, |
1118 | CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM); | |
1119 | } | |
a7fec7a7 | 1120 | |
1365611d PP |
1121 | if (cert_count < 0) |
1122 | { | |
1123 | rc = cert_count; | |
47195144 | 1124 | exim_gnutls_err_check(rc, US"setting certificate trust"); |
1365611d PP |
1125 | } |
1126 | DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", cert_count); | |
059ec3d9 | 1127 | |
5c8cda3a PP |
1128 | if (state->tls_crl && *state->tls_crl && |
1129 | state->exp_tls_crl && *state->exp_tls_crl) | |
1365611d | 1130 | { |
5c8cda3a PP |
1131 | DEBUG(D_tls) debug_printf("loading CRL file = %s\n", state->exp_tls_crl); |
1132 | cert_count = gnutls_certificate_set_x509_crl_file(state->x509_cred, | |
1133 | CS state->exp_tls_crl, GNUTLS_X509_FMT_PEM); | |
1134 | if (cert_count < 0) | |
1365611d | 1135 | { |
5c8cda3a | 1136 | rc = cert_count; |
47195144 | 1137 | exim_gnutls_err_check(rc, US"gnutls_certificate_set_x509_crl_file"); |
1365611d | 1138 | } |
5c8cda3a | 1139 | DEBUG(D_tls) debug_printf("Processed %d CRLs.\n", cert_count); |
1365611d | 1140 | } |
059ec3d9 | 1141 | |
059ec3d9 PH |
1142 | return OK; |
1143 | } | |
1144 | ||
1145 | ||
1146 | ||
1147 | ||
1365611d PP |
1148 | /************************************************* |
1149 | * Set X.509 state variables * | |
1150 | *************************************************/ | |
1151 | ||
1152 | /* In GnuTLS, the registered cert/key are not replaced by a later | |
1153 | set of a cert/key, so for SNI support we need a whole new x509_cred | |
1154 | structure. Which means various other non-re-expanded pieces of state | |
1155 | need to be re-set in the new struct, so the setting logic is pulled | |
1156 | out to this. | |
1157 | ||
1158 | Arguments: | |
1159 | state exim_gnutls_state_st * | |
cf0c6164 | 1160 | errstr error string pointer |
1365611d PP |
1161 | |
1162 | Returns: OK/DEFER/FAIL | |
1163 | */ | |
1164 | ||
1165 | static int | |
cf0c6164 | 1166 | tls_set_remaining_x509(exim_gnutls_state_st *state, uschar ** errstr) |
1365611d PP |
1167 | { |
1168 | int rc; | |
1169 | const host_item *host = state->host; /* macro should be reconsidered? */ | |
1170 | ||
1171 | /* Create D-H parameters, or read them from the cache file. This function does | |
1172 | its own SMTP error messaging. This only happens for the server, TLS D-H ignores | |
1173 | client-side params. */ | |
1174 | ||
1175 | if (!state->host) | |
1176 | { | |
1177 | if (!dh_server_params) | |
1178 | { | |
cf0c6164 | 1179 | rc = init_server_dh(errstr); |
1365611d PP |
1180 | if (rc != OK) return rc; |
1181 | } | |
1182 | gnutls_certificate_set_dh_params(state->x509_cred, dh_server_params); | |
1183 | } | |
1184 | ||
1185 | /* Link the credentials to the session. */ | |
1186 | ||
1187 | rc = gnutls_credentials_set(state->session, GNUTLS_CRD_CERTIFICATE, state->x509_cred); | |
47195144 | 1188 | exim_gnutls_err_check(rc, US"gnutls_credentials_set"); |
1365611d PP |
1189 | |
1190 | return OK; | |
1191 | } | |
1192 | ||
059ec3d9 | 1193 | /************************************************* |
17c76198 | 1194 | * Initialize for GnuTLS * |
059ec3d9 PH |
1195 | *************************************************/ |
1196 | ||
9196d5bf | 1197 | |
4fb7df6d JH |
1198 | #ifndef DISABLE_OCSP |
1199 | ||
9196d5bf JH |
1200 | static BOOL |
1201 | tls_is_buggy_ocsp(void) | |
1202 | { | |
1203 | const uschar * s; | |
1204 | uschar maj, mid, mic; | |
1205 | ||
1206 | s = CUS gnutls_check_version(NULL); | |
1207 | maj = atoi(CCS s); | |
1208 | if (maj == 3) | |
1209 | { | |
1210 | while (*s && *s != '.') s++; | |
1211 | mid = atoi(CCS ++s); | |
1212 | if (mid <= 2) | |
1213 | return TRUE; | |
1214 | else if (mid >= 5) | |
1215 | return FALSE; | |
1216 | else | |
1217 | { | |
1218 | while (*s && *s != '.') s++; | |
1219 | mic = atoi(CCS ++s); | |
1220 | return mic <= (mid == 3 ? 16 : 3); | |
1221 | } | |
1222 | } | |
1223 | return FALSE; | |
1224 | } | |
1225 | ||
4fb7df6d | 1226 | #endif |
9196d5bf JH |
1227 | |
1228 | ||
17c76198 PP |
1229 | /* Called from both server and client code. In the case of a server, errors |
1230 | before actual TLS negotiation return DEFER. | |
059ec3d9 PH |
1231 | |
1232 | Arguments: | |
17c76198 PP |
1233 | host connected host, if client; NULL if server |
1234 | certificate certificate file | |
1235 | privatekey private key file | |
1236 | sni TLS SNI to send, sometimes when client; else NULL | |
1237 | cas CA certs file | |
1238 | crl CRL file | |
1239 | require_ciphers tls_require_ciphers setting | |
817d9f57 | 1240 | caller_state returned state-info structure |
cf0c6164 | 1241 | errstr error string pointer |
059ec3d9 | 1242 | |
17c76198 | 1243 | Returns: OK/DEFER/FAIL |
059ec3d9 PH |
1244 | */ |
1245 | ||
17c76198 PP |
1246 | static int |
1247 | tls_init( | |
1248 | const host_item *host, | |
1249 | const uschar *certificate, | |
1250 | const uschar *privatekey, | |
1251 | const uschar *sni, | |
1252 | const uschar *cas, | |
1253 | const uschar *crl, | |
1254 | const uschar *require_ciphers, | |
cf0c6164 JH |
1255 | exim_gnutls_state_st **caller_state, |
1256 | uschar ** errstr) | |
059ec3d9 | 1257 | { |
17c76198 PP |
1258 | exim_gnutls_state_st *state; |
1259 | int rc; | |
1260 | size_t sz; | |
1261 | const char *errpos; | |
1262 | uschar *p; | |
1263 | BOOL want_default_priorities; | |
1264 | ||
1265 | if (!exim_gnutls_base_init_done) | |
059ec3d9 | 1266 | { |
17c76198 PP |
1267 | DEBUG(D_tls) debug_printf("GnuTLS global init required.\n"); |
1268 | ||
a5f239e4 PP |
1269 | #ifdef HAVE_GNUTLS_PKCS11 |
1270 | /* By default, gnutls_global_init will init PKCS11 support in auto mode, | |
1271 | which loads modules from a config file, which sounds good and may be wanted | |
1272 | by some sysadmin, but also means in common configurations that GNOME keyring | |
1273 | environment variables are used and so breaks for users calling mailq. | |
1274 | To prevent this, we init PKCS11 first, which is the documented approach. */ | |
2519e60d | 1275 | if (!gnutls_allow_auto_pkcs11) |
a5f239e4 PP |
1276 | { |
1277 | rc = gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL); | |
47195144 | 1278 | exim_gnutls_err_check(rc, US"gnutls_pkcs11_init"); |
a5f239e4 PP |
1279 | } |
1280 | #endif | |
1281 | ||
17c76198 | 1282 | rc = gnutls_global_init(); |
47195144 | 1283 | exim_gnutls_err_check(rc, US"gnutls_global_init"); |
17c76198 PP |
1284 | |
1285 | #if EXIM_GNUTLS_LIBRARY_LOG_LEVEL >= 0 | |
1286 | DEBUG(D_tls) | |
059ec3d9 | 1287 | { |
17c76198 PP |
1288 | gnutls_global_set_log_function(exim_gnutls_logger_cb); |
1289 | /* arbitrarily chosen level; bump upto 9 for more */ | |
1290 | gnutls_global_set_log_level(EXIM_GNUTLS_LIBRARY_LOG_LEVEL); | |
059ec3d9 | 1291 | } |
17c76198 PP |
1292 | #endif |
1293 | ||
4fb7df6d JH |
1294 | #ifndef DISABLE_OCSP |
1295 | if (tls_ocsp_file && (gnutls_buggy_ocsp = tls_is_buggy_ocsp())) | |
9196d5bf | 1296 | log_write(0, LOG_MAIN, "OCSP unusable with this GnuTLS library version"); |
4fb7df6d | 1297 | #endif |
9196d5bf | 1298 | |
17c76198 | 1299 | exim_gnutls_base_init_done = TRUE; |
059ec3d9 | 1300 | } |
059ec3d9 | 1301 | |
17c76198 PP |
1302 | if (host) |
1303 | { | |
1304 | state = &state_client; | |
1305 | memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init)); | |
817d9f57 | 1306 | state->tlsp = &tls_out; |
17c76198 PP |
1307 | DEBUG(D_tls) debug_printf("initialising GnuTLS client session\n"); |
1308 | rc = gnutls_init(&state->session, GNUTLS_CLIENT); | |
1309 | } | |
1310 | else | |
1311 | { | |
1312 | state = &state_server; | |
1313 | memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init)); | |
817d9f57 | 1314 | state->tlsp = &tls_in; |
17c76198 PP |
1315 | DEBUG(D_tls) debug_printf("initialising GnuTLS server session\n"); |
1316 | rc = gnutls_init(&state->session, GNUTLS_SERVER); | |
1317 | } | |
47195144 | 1318 | exim_gnutls_err_check(rc, US"gnutls_init"); |
059ec3d9 | 1319 | |
17c76198 | 1320 | state->host = host; |
059ec3d9 | 1321 | |
17c76198 PP |
1322 | state->tls_certificate = certificate; |
1323 | state->tls_privatekey = privatekey; | |
5779e6aa | 1324 | state->tls_require_ciphers = require_ciphers; |
17c76198 PP |
1325 | state->tls_sni = sni; |
1326 | state->tls_verify_certificates = cas; | |
1327 | state->tls_crl = crl; | |
059ec3d9 | 1328 | |
17c76198 PP |
1329 | /* This handles the variables that might get re-expanded after TLS SNI; |
1330 | that's tls_certificate, tls_privatekey, tls_verify_certificates, tls_crl */ | |
059ec3d9 | 1331 | |
17c76198 PP |
1332 | DEBUG(D_tls) |
1333 | debug_printf("Expanding various TLS configuration options for session credentials.\n"); | |
cf0c6164 | 1334 | if ((rc = tls_expand_session_files(state, errstr)) != OK) return rc; |
059ec3d9 | 1335 | |
1365611d PP |
1336 | /* These are all other parts of the x509_cred handling, since SNI in GnuTLS |
1337 | requires a new structure afterwards. */ | |
83da1223 | 1338 | |
cf0c6164 | 1339 | if ((rc = tls_set_remaining_x509(state, errstr)) != OK) return rc; |
83da1223 | 1340 | |
17c76198 PP |
1341 | /* set SNI in client, only */ |
1342 | if (host) | |
1343 | { | |
cf0c6164 | 1344 | if (!expand_check(sni, US"tls_out_sni", &state->tlsp->sni, errstr)) |
17c76198 | 1345 | return DEFER; |
0df4ab80 | 1346 | if (state->tlsp->sni && *state->tlsp->sni) |
17c76198 PP |
1347 | { |
1348 | DEBUG(D_tls) | |
0df4ab80 JH |
1349 | debug_printf("Setting TLS client SNI to \"%s\"\n", state->tlsp->sni); |
1350 | sz = Ustrlen(state->tlsp->sni); | |
17c76198 | 1351 | rc = gnutls_server_name_set(state->session, |
0df4ab80 | 1352 | GNUTLS_NAME_DNS, state->tlsp->sni, sz); |
47195144 | 1353 | exim_gnutls_err_check(rc, US"gnutls_server_name_set"); |
17c76198 PP |
1354 | } |
1355 | } | |
1356 | else if (state->tls_sni) | |
1357 | DEBUG(D_tls) debug_printf("*** PROBABLY A BUG *** " \ | |
ba86e143 | 1358 | "have an SNI set for a server [%s]\n", state->tls_sni); |
83da1223 | 1359 | |
17c76198 | 1360 | /* This is the priority string support, |
42bfef1e | 1361 | http://www.gnutls.org/manual/html_node/Priority-Strings.html |
17c76198 PP |
1362 | and replaces gnutls_require_kx, gnutls_require_mac & gnutls_require_protocols. |
1363 | This was backwards incompatible, but means Exim no longer needs to track | |
1364 | all algorithms and provide string forms for them. */ | |
83da1223 | 1365 | |
17c76198 | 1366 | want_default_priorities = TRUE; |
83da1223 | 1367 | |
17c76198 | 1368 | if (state->tls_require_ciphers && *state->tls_require_ciphers) |
83da1223 | 1369 | { |
cf0c6164 | 1370 | if (!expand_check_tlsvar(tls_require_ciphers, errstr)) |
17c76198 PP |
1371 | return DEFER; |
1372 | if (state->exp_tls_require_ciphers && *state->exp_tls_require_ciphers) | |
83da1223 | 1373 | { |
17c76198 PP |
1374 | DEBUG(D_tls) debug_printf("GnuTLS session cipher/priority \"%s\"\n", |
1375 | state->exp_tls_require_ciphers); | |
1376 | ||
1377 | rc = gnutls_priority_init(&state->priority_cache, | |
1378 | CS state->exp_tls_require_ciphers, &errpos); | |
1379 | want_default_priorities = FALSE; | |
1380 | p = state->exp_tls_require_ciphers; | |
83da1223 PH |
1381 | } |
1382 | } | |
17c76198 PP |
1383 | if (want_default_priorities) |
1384 | { | |
83e2f8a2 PP |
1385 | DEBUG(D_tls) |
1386 | debug_printf("GnuTLS using default session cipher/priority \"%s\"\n", | |
1387 | exim_default_gnutls_priority); | |
17c76198 PP |
1388 | rc = gnutls_priority_init(&state->priority_cache, |
1389 | exim_default_gnutls_priority, &errpos); | |
1390 | p = US exim_default_gnutls_priority; | |
1391 | } | |
83da1223 | 1392 | |
47195144 | 1393 | exim_gnutls_err_check(rc, string_sprintf( |
17c76198 PP |
1394 | "gnutls_priority_init(%s) failed at offset %ld, \"%.6s..\"", |
1395 | p, errpos - CS p, errpos)); | |
1396 | ||
1397 | rc = gnutls_priority_set(state->session, state->priority_cache); | |
47195144 | 1398 | exim_gnutls_err_check(rc, US"gnutls_priority_set"); |
17c76198 PP |
1399 | |
1400 | gnutls_db_set_cache_expiration(state->session, ssl_session_timeout); | |
1401 | ||
1402 | /* Reduce security in favour of increased compatibility, if the admin | |
1403 | decides to make that trade-off. */ | |
1404 | if (gnutls_compat_mode) | |
83da1223 | 1405 | { |
17c76198 PP |
1406 | #if LIBGNUTLS_VERSION_NUMBER >= 0x020104 |
1407 | DEBUG(D_tls) debug_printf("lowering GnuTLS security, compatibility mode\n"); | |
1408 | gnutls_session_enable_compatibility_mode(state->session); | |
1409 | #else | |
1410 | DEBUG(D_tls) debug_printf("Unable to set gnutls_compat_mode - GnuTLS version too old\n"); | |
1411 | #endif | |
83da1223 PH |
1412 | } |
1413 | ||
17c76198 | 1414 | *caller_state = state; |
17c76198 | 1415 | return OK; |
83da1223 PH |
1416 | } |
1417 | ||
1418 | ||
1419 | ||
059ec3d9 | 1420 | /************************************************* |
17c76198 | 1421 | * Extract peer information * |
059ec3d9 PH |
1422 | *************************************************/ |
1423 | ||
17c76198 | 1424 | /* Called from both server and client code. |
4fe99a6c PP |
1425 | Only this is allowed to set state->peerdn and state->have_set_peerdn |
1426 | and we use that to detect double-calls. | |
059ec3d9 | 1427 | |
75fe387d PP |
1428 | NOTE: the state blocks last while the TLS connection is up, which is fine |
1429 | for logging in the server side, but for the client side, we log after teardown | |
1430 | in src/deliver.c. While the session is up, we can twist about states and | |
1431 | repoint tls_* globals, but those variables used for logging or other variable | |
1432 | expansion that happens _after_ delivery need to have a longer life-time. | |
1433 | ||
1434 | So for those, we get the data from POOL_PERM; the re-invoke guard keeps us from | |
1435 | doing this more than once per generation of a state context. We set them in | |
1436 | the state context, and repoint tls_* to them. After the state goes away, the | |
1437 | tls_* copies of the pointers remain valid and client delivery logging is happy. | |
1438 | ||
1439 | tls_certificate_verified is a BOOL, so the tls_peerdn and tls_cipher issues | |
1440 | don't apply. | |
1441 | ||
059ec3d9 | 1442 | Arguments: |
17c76198 | 1443 | state exim_gnutls_state_st * |
cf0c6164 | 1444 | errstr pointer to error string |
059ec3d9 | 1445 | |
17c76198 | 1446 | Returns: OK/DEFER/FAIL |
059ec3d9 PH |
1447 | */ |
1448 | ||
17c76198 | 1449 | static int |
cf0c6164 | 1450 | peer_status(exim_gnutls_state_st *state, uschar ** errstr) |
059ec3d9 | 1451 | { |
75fe387d | 1452 | uschar cipherbuf[256]; |
27f19eb4 | 1453 | const gnutls_datum_t *cert_list; |
75fe387d | 1454 | int old_pool, rc; |
17c76198 | 1455 | unsigned int cert_list_size = 0; |
4fe99a6c PP |
1456 | gnutls_protocol_t protocol; |
1457 | gnutls_cipher_algorithm_t cipher; | |
1458 | gnutls_kx_algorithm_t kx; | |
1459 | gnutls_mac_algorithm_t mac; | |
17c76198 PP |
1460 | gnutls_certificate_type_t ct; |
1461 | gnutls_x509_crt_t crt; | |
4fe99a6c | 1462 | uschar *p, *dn_buf; |
17c76198 | 1463 | size_t sz; |
059ec3d9 | 1464 | |
4fe99a6c | 1465 | if (state->have_set_peerdn) |
17c76198 | 1466 | return OK; |
4fe99a6c | 1467 | state->have_set_peerdn = TRUE; |
059ec3d9 | 1468 | |
4fe99a6c | 1469 | state->peerdn = NULL; |
059ec3d9 | 1470 | |
4fe99a6c PP |
1471 | /* tls_cipher */ |
1472 | cipher = gnutls_cipher_get(state->session); | |
1473 | protocol = gnutls_protocol_get_version(state->session); | |
1474 | mac = gnutls_mac_get(state->session); | |
1475 | kx = gnutls_kx_get(state->session); | |
1476 | ||
75fe387d | 1477 | string_format(cipherbuf, sizeof(cipherbuf), |
4fe99a6c PP |
1478 | "%s:%s:%d", |
1479 | gnutls_protocol_get_name(protocol), | |
1480 | gnutls_cipher_suite_get_name(kx, cipher, mac), | |
1481 | (int) gnutls_cipher_get_key_size(cipher) * 8); | |
1482 | ||
1483 | /* I don't see a way that spaces could occur, in the current GnuTLS | |
1484 | code base, but it was a concern in the old code and perhaps older GnuTLS | |
1485 | releases did return "TLS 1.0"; play it safe, just in case. */ | |
75fe387d | 1486 | for (p = cipherbuf; *p != '\0'; ++p) |
4fe99a6c PP |
1487 | if (isspace(*p)) |
1488 | *p = '-'; | |
75fe387d PP |
1489 | old_pool = store_pool; |
1490 | store_pool = POOL_PERM; | |
1491 | state->ciphersuite = string_copy(cipherbuf); | |
1492 | store_pool = old_pool; | |
817d9f57 | 1493 | state->tlsp->cipher = state->ciphersuite; |
4fe99a6c PP |
1494 | |
1495 | /* tls_peerdn */ | |
17c76198 | 1496 | cert_list = gnutls_certificate_get_peers(state->session, &cert_list_size); |
83da1223 | 1497 | |
17c76198 PP |
1498 | if (cert_list == NULL || cert_list_size == 0) |
1499 | { | |
17c76198 PP |
1500 | DEBUG(D_tls) debug_printf("TLS: no certificate from peer (%p & %d)\n", |
1501 | cert_list, cert_list_size); | |
e51c7be2 | 1502 | if (state->verify_requirement >= VERIFY_REQUIRED) |
17c76198 | 1503 | return tls_error(US"certificate verification failed", |
cf0c6164 | 1504 | "no certificate received from peer", state->host, errstr); |
17c76198 PP |
1505 | return OK; |
1506 | } | |
059ec3d9 | 1507 | |
17c76198 PP |
1508 | ct = gnutls_certificate_type_get(state->session); |
1509 | if (ct != GNUTLS_CRT_X509) | |
059ec3d9 | 1510 | { |
17c76198 | 1511 | const char *ctn = gnutls_certificate_type_get_name(ct); |
17c76198 PP |
1512 | DEBUG(D_tls) |
1513 | debug_printf("TLS: peer cert not X.509 but instead \"%s\"\n", ctn); | |
e51c7be2 | 1514 | if (state->verify_requirement >= VERIFY_REQUIRED) |
17c76198 | 1515 | return tls_error(US"certificate verification not possible, unhandled type", |
cf0c6164 | 1516 | ctn, state->host, errstr); |
17c76198 | 1517 | return OK; |
83da1223 | 1518 | } |
059ec3d9 | 1519 | |
e51c7be2 JH |
1520 | #define exim_gnutls_peer_err(Label) \ |
1521 | do { \ | |
1522 | if (rc != GNUTLS_E_SUCCESS) \ | |
1523 | { \ | |
1524 | DEBUG(D_tls) debug_printf("TLS: peer cert problem: %s: %s\n", \ | |
1525 | (Label), gnutls_strerror(rc)); \ | |
1526 | if (state->verify_requirement >= VERIFY_REQUIRED) \ | |
cf0c6164 | 1527 | return tls_error((Label), gnutls_strerror(rc), state->host, errstr); \ |
e51c7be2 JH |
1528 | return OK; \ |
1529 | } \ | |
1530 | } while (0) | |
17c76198 | 1531 | |
9d1c15ef JH |
1532 | rc = import_cert(&cert_list[0], &crt); |
1533 | exim_gnutls_peer_err(US"cert 0"); | |
1534 | ||
1535 | state->tlsp->peercert = state->peercert = crt; | |
17c76198 | 1536 | |
17c76198 PP |
1537 | sz = 0; |
1538 | rc = gnutls_x509_crt_get_dn(crt, NULL, &sz); | |
1539 | if (rc != GNUTLS_E_SHORT_MEMORY_BUFFER) | |
83da1223 | 1540 | { |
17c76198 PP |
1541 | exim_gnutls_peer_err(US"getting size for cert DN failed"); |
1542 | return FAIL; /* should not happen */ | |
059ec3d9 | 1543 | } |
17c76198 PP |
1544 | dn_buf = store_get_perm(sz); |
1545 | rc = gnutls_x509_crt_get_dn(crt, CS dn_buf, &sz); | |
1546 | exim_gnutls_peer_err(US"failed to extract certificate DN [gnutls_x509_crt_get_dn(cert 0)]"); | |
9d1c15ef | 1547 | |
17c76198 PP |
1548 | state->peerdn = dn_buf; |
1549 | ||
1550 | return OK; | |
1551 | #undef exim_gnutls_peer_err | |
1552 | } | |
059ec3d9 | 1553 | |
059ec3d9 | 1554 | |
059ec3d9 | 1555 | |
059ec3d9 | 1556 | |
17c76198 PP |
1557 | /************************************************* |
1558 | * Verify peer certificate * | |
1559 | *************************************************/ | |
059ec3d9 | 1560 | |
17c76198 PP |
1561 | /* Called from both server and client code. |
1562 | *Should* be using a callback registered with | |
1563 | gnutls_certificate_set_verify_function() to fail the handshake if we dislike | |
1564 | the peer information, but that's too new for some OSes. | |
059ec3d9 | 1565 | |
17c76198 | 1566 | Arguments: |
899b8bbc JH |
1567 | state exim_gnutls_state_st * |
1568 | errstr where to put an error message | |
059ec3d9 | 1569 | |
17c76198 PP |
1570 | Returns: |
1571 | FALSE if the session should be rejected | |
1572 | TRUE if the cert is okay or we just don't care | |
1573 | */ | |
059ec3d9 | 1574 | |
17c76198 | 1575 | static BOOL |
cf0c6164 | 1576 | verify_certificate(exim_gnutls_state_st *state, uschar ** errstr) |
17c76198 PP |
1577 | { |
1578 | int rc; | |
899b8bbc JH |
1579 | uint verify; |
1580 | ||
1581 | if (state->verify_requirement == VERIFY_NONE) | |
1582 | return TRUE; | |
17c76198 | 1583 | |
cf0c6164 | 1584 | *errstr = NULL; |
17c76198 | 1585 | |
cf0c6164 | 1586 | if ((rc = peer_status(state, errstr)) != OK) |
e6060e2c | 1587 | { |
17c76198 | 1588 | verify = GNUTLS_CERT_INVALID; |
cf0c6164 | 1589 | *errstr = US"certificate not supplied"; |
17c76198 PP |
1590 | } |
1591 | else | |
899b8bbc JH |
1592 | |
1593 | { | |
1594 | #ifdef SUPPORT_DANE | |
1595 | if (state->verify_requirement == VERIFY_DANE && state->host) | |
1596 | { | |
1597 | /* Using dane_verify_session_crt() would be easy, as it does it all for us | |
1598 | including talking to a DNS resolver. But we want to do that bit ourselves | |
1599 | as the testsuite intercepts and fakes its own DNS environment. */ | |
1600 | ||
1601 | dane_state_t s; | |
1602 | dane_query_t r; | |
1603 | const gnutls_datum_t * certlist; | |
1604 | uint lsize; | |
1605 | ||
1606 | certlist = gnutls_certificate_get_peers(state->session, &lsize); | |
1607 | ||
1608 | if ( (rc = dane_state_init(&s, 0)) | |
1609 | || (rc = dane_raw_tlsa(s, &r, state->dane_data, state->dane_data_len, | |
1610 | 1, 0)) | |
1611 | || (rc = dane_verify_crt_raw(s, certlist, lsize, | |
1612 | gnutls_certificate_type_get(state->session), | |
1613 | r, 0, 0, &verify)) | |
1614 | ) | |
1615 | ||
1616 | { | |
1617 | *errstr = string_sprintf("TLSA record problem: %s", dane_strerror(rc)); | |
1618 | goto badcert; | |
1619 | } | |
1620 | if (verify != 0) | |
1621 | { | |
1622 | gnutls_datum_t str; | |
1623 | (void) dane_verification_status_print(verify, &str, 0); | |
1624 | *errstr = US str.data; /* don't bother to free */ | |
1625 | goto badcert; | |
1626 | } | |
1627 | state->peer_dane_verified = TRUE; | |
1628 | } | |
1629 | #endif | |
1630 | ||
17c76198 | 1631 | rc = gnutls_certificate_verify_peers2(state->session, &verify); |
899b8bbc | 1632 | } |
e6060e2c | 1633 | |
899b8bbc | 1634 | /* Handle the result of verification. INVALID is set if any others are. */ |
059ec3d9 | 1635 | |
e51c7be2 JH |
1636 | if (rc < 0 || |
1637 | verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED) | |
1638 | ) | |
17c76198 PP |
1639 | { |
1640 | state->peer_cert_verified = FALSE; | |
cf0c6164 JH |
1641 | if (!*errstr) |
1642 | *errstr = verify & GNUTLS_CERT_REVOKED | |
1643 | ? US"certificate revoked" : US"certificate invalid"; | |
059ec3d9 | 1644 | |
17c76198 | 1645 | DEBUG(D_tls) |
e51c7be2 | 1646 | debug_printf("TLS certificate verification failed (%s): peerdn=\"%s\"\n", |
cf0c6164 | 1647 | *errstr, state->peerdn ? state->peerdn : US"<unset>"); |
059ec3d9 | 1648 | |
e51c7be2 | 1649 | if (state->verify_requirement >= VERIFY_REQUIRED) |
899b8bbc | 1650 | goto badcert; |
17c76198 | 1651 | DEBUG(D_tls) |
4789da3a | 1652 | debug_printf("TLS verify failure overridden (host in tls_try_verify_hosts)\n"); |
17c76198 | 1653 | } |
e51c7be2 | 1654 | |
17c76198 PP |
1655 | else |
1656 | { | |
aa2a70ba | 1657 | if (state->exp_tls_verify_cert_hostnames) |
e51c7be2 JH |
1658 | { |
1659 | int sep = 0; | |
55414b25 | 1660 | const uschar * list = state->exp_tls_verify_cert_hostnames; |
e51c7be2 | 1661 | uschar * name; |
76075bb5 | 1662 | while ((name = string_nextinlist(&list, &sep, NULL, 0))) |
e51c7be2 JH |
1663 | if (gnutls_x509_crt_check_hostname(state->tlsp->peercert, CS name)) |
1664 | break; | |
1665 | if (!name) | |
1666 | { | |
1667 | DEBUG(D_tls) | |
1668 | debug_printf("TLS certificate verification failed: cert name mismatch\n"); | |
aa2a70ba | 1669 | if (state->verify_requirement >= VERIFY_REQUIRED) |
899b8bbc | 1670 | goto badcert; |
aa2a70ba | 1671 | return TRUE; |
e51c7be2 JH |
1672 | } |
1673 | } | |
17c76198 | 1674 | state->peer_cert_verified = TRUE; |
e51c7be2 | 1675 | DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=\"%s\"\n", |
4fe99a6c | 1676 | state->peerdn ? state->peerdn : US"<unset>"); |
17c76198 | 1677 | } |
059ec3d9 | 1678 | |
817d9f57 | 1679 | state->tlsp->peerdn = state->peerdn; |
17c76198 | 1680 | return TRUE; |
899b8bbc JH |
1681 | |
1682 | badcert: | |
1683 | gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE); | |
1684 | return FALSE; | |
17c76198 | 1685 | } |
059ec3d9 | 1686 | |
17c76198 PP |
1687 | |
1688 | ||
1689 | ||
1690 | /* ------------------------------------------------------------------------ */ | |
1691 | /* Callbacks */ | |
1692 | ||
1693 | /* Logging function which can be registered with | |
1694 | * gnutls_global_set_log_function() | |
1695 | * gnutls_global_set_log_level() 0..9 | |
1696 | */ | |
af3498d6 | 1697 | #if EXIM_GNUTLS_LIBRARY_LOG_LEVEL >= 0 |
059ec3d9 | 1698 | static void |
17c76198 | 1699 | exim_gnutls_logger_cb(int level, const char *message) |
059ec3d9 | 1700 | { |
8c79eebf PP |
1701 | size_t len = strlen(message); |
1702 | if (len < 1) | |
1703 | { | |
1704 | DEBUG(D_tls) debug_printf("GnuTLS<%d> empty debug message\n", level); | |
1705 | return; | |
1706 | } | |
1707 | DEBUG(D_tls) debug_printf("GnuTLS<%d>: %s%s", level, message, | |
1708 | message[len-1] == '\n' ? "" : "\n"); | |
17c76198 | 1709 | } |
af3498d6 | 1710 | #endif |
059ec3d9 | 1711 | |
059ec3d9 | 1712 | |
17c76198 PP |
1713 | /* Called after client hello, should handle SNI work. |
1714 | This will always set tls_sni (state->received_sni) if available, | |
1715 | and may trigger presenting different certificates, | |
1716 | if state->trigger_sni_changes is TRUE. | |
059ec3d9 | 1717 | |
17c76198 PP |
1718 | Should be registered with |
1719 | gnutls_handshake_set_post_client_hello_function() | |
059ec3d9 | 1720 | |
17c76198 PP |
1721 | "This callback must return 0 on success or a gnutls error code to terminate the |
1722 | handshake.". | |
059ec3d9 | 1723 | |
17c76198 PP |
1724 | For inability to get SNI information, we return 0. |
1725 | We only return non-zero if re-setup failed. | |
817d9f57 | 1726 | Only used for server-side TLS. |
17c76198 | 1727 | */ |
44bbabb5 | 1728 | |
17c76198 PP |
1729 | static int |
1730 | exim_sni_handling_cb(gnutls_session_t session) | |
1731 | { | |
1732 | char sni_name[MAX_HOST_LEN]; | |
1733 | size_t data_len = MAX_HOST_LEN; | |
817d9f57 | 1734 | exim_gnutls_state_st *state = &state_server; |
17c76198 PP |
1735 | unsigned int sni_type; |
1736 | int rc, old_pool; | |
cf0c6164 | 1737 | uschar * dummy_errstr; |
17c76198 PP |
1738 | |
1739 | rc = gnutls_server_name_get(session, sni_name, &data_len, &sni_type, 0); | |
b34fc30c PP |
1740 | if (rc != GNUTLS_E_SUCCESS) |
1741 | { | |
1742 | DEBUG(D_tls) { | |
1743 | if (rc == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) | |
1744 | debug_printf("TLS: no SNI presented in handshake.\n"); | |
1745 | else | |
1746 | debug_printf("TLS failure: gnutls_server_name_get(): %s [%d]\n", | |
1747 | gnutls_strerror(rc), rc); | |
cf0c6164 | 1748 | } |
b34fc30c PP |
1749 | return 0; |
1750 | } | |
1751 | ||
17c76198 PP |
1752 | if (sni_type != GNUTLS_NAME_DNS) |
1753 | { | |
1754 | DEBUG(D_tls) debug_printf("TLS: ignoring SNI of unhandled type %u\n", sni_type); | |
1755 | return 0; | |
1756 | } | |
44bbabb5 | 1757 | |
17c76198 PP |
1758 | /* We now have a UTF-8 string in sni_name */ |
1759 | old_pool = store_pool; | |
1760 | store_pool = POOL_PERM; | |
1761 | state->received_sni = string_copyn(US sni_name, data_len); | |
1762 | store_pool = old_pool; | |
1763 | ||
1764 | /* We set this one now so that variable expansions below will work */ | |
817d9f57 | 1765 | state->tlsp->sni = state->received_sni; |
17c76198 PP |
1766 | |
1767 | DEBUG(D_tls) debug_printf("Received TLS SNI \"%s\"%s\n", sni_name, | |
1768 | state->trigger_sni_changes ? "" : " (unused for certificate selection)"); | |
1769 | ||
1770 | if (!state->trigger_sni_changes) | |
1771 | return 0; | |
1772 | ||
cf0c6164 | 1773 | if ((rc = tls_expand_session_files(state, &dummy_errstr)) != OK) |
17c76198 PP |
1774 | { |
1775 | /* If the setup of certs/etc failed before handshake, TLS would not have | |
1776 | been offered. The best we can do now is abort. */ | |
1777 | return GNUTLS_E_APPLICATION_ERROR_MIN; | |
1778 | } | |
1779 | ||
cf0c6164 | 1780 | rc = tls_set_remaining_x509(state, &dummy_errstr); |
1365611d PP |
1781 | if (rc != OK) return GNUTLS_E_APPLICATION_ERROR_MIN; |
1782 | ||
1783 | return 0; | |
059ec3d9 PH |
1784 | } |
1785 | ||
1786 | ||
1787 | ||
f2de3a33 | 1788 | #ifndef DISABLE_OCSP |
44662487 JH |
1789 | |
1790 | static int | |
1791 | server_ocsp_stapling_cb(gnutls_session_t session, void * ptr, | |
1792 | gnutls_datum_t * ocsp_response) | |
1793 | { | |
1794 | int ret; | |
47195144 | 1795 | DEBUG(D_tls) debug_printf("OCSP stapling callback: %s\n", US ptr); |
44662487 | 1796 | |
44662487 JH |
1797 | if ((ret = gnutls_load_file(ptr, ocsp_response)) < 0) |
1798 | { | |
1799 | DEBUG(D_tls) debug_printf("Failed to load ocsp stapling file %s\n", | |
5903c6ff | 1800 | CS ptr); |
018058b2 | 1801 | tls_in.ocsp = OCSP_NOT_RESP; |
44662487 JH |
1802 | return GNUTLS_E_NO_CERTIFICATE_STATUS; |
1803 | } | |
1804 | ||
018058b2 | 1805 | tls_in.ocsp = OCSP_VFY_NOT_TRIED; |
44662487 JH |
1806 | return 0; |
1807 | } | |
1808 | ||
1809 | #endif | |
1810 | ||
1811 | ||
0cbf2b82 | 1812 | #ifndef DISABLE_EVENT |
a7538db1 JH |
1813 | /* |
1814 | We use this callback to get observability and detail-level control | |
723fe533 JH |
1815 | for an exim TLS connection (either direction), raising a tls:cert event |
1816 | for each cert in the chain presented by the peer. Any event | |
a7538db1 JH |
1817 | can deny verification. |
1818 | ||
1819 | Return 0 for the handshake to continue or non-zero to terminate. | |
1820 | */ | |
1821 | ||
1822 | static int | |
723fe533 | 1823 | verify_cb(gnutls_session_t session) |
a7538db1 | 1824 | { |
27f19eb4 | 1825 | const gnutls_datum_t * cert_list; |
a7538db1 JH |
1826 | unsigned int cert_list_size = 0; |
1827 | gnutls_x509_crt_t crt; | |
1828 | int rc; | |
b30275b8 | 1829 | uschar * yield; |
a7538db1 JH |
1830 | exim_gnutls_state_st * state = gnutls_session_get_ptr(session); |
1831 | ||
1832 | cert_list = gnutls_certificate_get_peers(session, &cert_list_size); | |
1833 | if (cert_list) | |
1834 | while (cert_list_size--) | |
1835 | { | |
1836 | rc = import_cert(&cert_list[cert_list_size], &crt); | |
1837 | if (rc != GNUTLS_E_SUCCESS) | |
1838 | { | |
1839 | DEBUG(D_tls) debug_printf("TLS: peer cert problem: depth %d: %s\n", | |
1840 | cert_list_size, gnutls_strerror(rc)); | |
1841 | break; | |
1842 | } | |
1843 | ||
1844 | state->tlsp->peercert = crt; | |
b30275b8 JH |
1845 | if ((yield = event_raise(state->event_action, |
1846 | US"tls:cert", string_sprintf("%d", cert_list_size)))) | |
a7538db1 JH |
1847 | { |
1848 | log_write(0, LOG_MAIN, | |
b30275b8 JH |
1849 | "SSL verify denied by event-action: depth=%d: %s", |
1850 | cert_list_size, yield); | |
a7538db1 JH |
1851 | return 1; /* reject */ |
1852 | } | |
1853 | state->tlsp->peercert = NULL; | |
1854 | } | |
1855 | ||
1856 | return 0; | |
1857 | } | |
1858 | ||
1859 | #endif | |
44662487 JH |
1860 | |
1861 | ||
17c76198 PP |
1862 | |
1863 | /* ------------------------------------------------------------------------ */ | |
1864 | /* Exported functions */ | |
1865 | ||
1866 | ||
1867 | ||
1868 | ||
059ec3d9 PH |
1869 | /************************************************* |
1870 | * Start a TLS session in a server * | |
1871 | *************************************************/ | |
1872 | ||
1873 | /* This is called when Exim is running as a server, after having received | |
1874 | the STARTTLS command. It must respond to that command, and then negotiate | |
1875 | a TLS session. | |
1876 | ||
1877 | Arguments: | |
83da1223 | 1878 | require_ciphers list of allowed ciphers or NULL |
cf0c6164 | 1879 | errstr pointer to error string |
059ec3d9 PH |
1880 | |
1881 | Returns: OK on success | |
1882 | DEFER for errors before the start of the negotiation | |
4c04137d | 1883 | FAIL for errors during the negotiation; the server can't |
059ec3d9 PH |
1884 | continue running. |
1885 | */ | |
1886 | ||
1887 | int | |
cf0c6164 | 1888 | tls_server_start(const uschar * require_ciphers, uschar ** errstr) |
059ec3d9 PH |
1889 | { |
1890 | int rc; | |
cf0c6164 | 1891 | exim_gnutls_state_st * state = NULL; |
059ec3d9 PH |
1892 | |
1893 | /* Check for previous activation */ | |
817d9f57 | 1894 | if (tls_in.active >= 0) |
059ec3d9 | 1895 | { |
cf0c6164 | 1896 | tls_error(US"STARTTLS received after TLS started", "", NULL, errstr); |
925ac8e4 | 1897 | smtp_printf("554 Already in TLS\r\n", FALSE); |
059ec3d9 PH |
1898 | return FAIL; |
1899 | } | |
1900 | ||
1901 | /* Initialize the library. If it fails, it will already have logged the error | |
1902 | and sent an SMTP response. */ | |
1903 | ||
17c76198 | 1904 | DEBUG(D_tls) debug_printf("initialising GnuTLS as a server\n"); |
059ec3d9 | 1905 | |
cf0c6164 | 1906 | if ((rc = tls_init(NULL, tls_certificate, tls_privatekey, |
17c76198 | 1907 | NULL, tls_verify_certificates, tls_crl, |
cf0c6164 | 1908 | require_ciphers, &state, errstr)) != OK) return rc; |
059ec3d9 | 1909 | |
059ec3d9 PH |
1910 | /* If this is a host for which certificate verification is mandatory or |
1911 | optional, set up appropriately. */ | |
1912 | ||
059ec3d9 | 1913 | if (verify_check_host(&tls_verify_hosts) == OK) |
17c76198 | 1914 | { |
e51c7be2 JH |
1915 | DEBUG(D_tls) |
1916 | debug_printf("TLS: a client certificate will be required.\n"); | |
17c76198 PP |
1917 | state->verify_requirement = VERIFY_REQUIRED; |
1918 | gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE); | |
1919 | } | |
059ec3d9 | 1920 | else if (verify_check_host(&tls_try_verify_hosts) == OK) |
17c76198 | 1921 | { |
e51c7be2 JH |
1922 | DEBUG(D_tls) |
1923 | debug_printf("TLS: a client certificate will be requested but not required.\n"); | |
17c76198 PP |
1924 | state->verify_requirement = VERIFY_OPTIONAL; |
1925 | gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUEST); | |
1926 | } | |
1927 | else | |
1928 | { | |
e51c7be2 JH |
1929 | DEBUG(D_tls) |
1930 | debug_printf("TLS: a client certificate will not be requested.\n"); | |
17c76198 PP |
1931 | state->verify_requirement = VERIFY_NONE; |
1932 | gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_IGNORE); | |
1933 | } | |
059ec3d9 | 1934 | |
0cbf2b82 | 1935 | #ifndef DISABLE_EVENT |
723fe533 JH |
1936 | if (event_action) |
1937 | { | |
1938 | state->event_action = event_action; | |
1939 | gnutls_session_set_ptr(state->session, state); | |
1940 | gnutls_certificate_set_verify_function(state->x509_cred, verify_cb); | |
1941 | } | |
1942 | #endif | |
1943 | ||
17c76198 PP |
1944 | /* Register SNI handling; always, even if not in tls_certificate, so that the |
1945 | expansion variable $tls_sni is always available. */ | |
059ec3d9 | 1946 | |
17c76198 PP |
1947 | gnutls_handshake_set_post_client_hello_function(state->session, |
1948 | exim_sni_handling_cb); | |
059ec3d9 PH |
1949 | |
1950 | /* Set context and tell client to go ahead, except in the case of TLS startup | |
1951 | on connection, where outputting anything now upsets the clients and tends to | |
1952 | make them disconnect. We need to have an explicit fflush() here, to force out | |
1953 | the response. Other smtp_printf() calls do not need it, because in non-TLS | |
1954 | mode, the fflush() happens when smtp_getc() is called. */ | |
1955 | ||
817d9f57 | 1956 | if (!state->tlsp->on_connect) |
059ec3d9 | 1957 | { |
925ac8e4 | 1958 | smtp_printf("220 TLS go ahead\r\n", FALSE); |
9d1c15ef | 1959 | fflush(smtp_out); |
059ec3d9 PH |
1960 | } |
1961 | ||
1962 | /* Now negotiate the TLS session. We put our own timer on it, since it seems | |
1963 | that the GnuTLS library doesn't. */ | |
1964 | ||
17c76198 | 1965 | gnutls_transport_set_ptr2(state->session, |
27f19eb4 JH |
1966 | (gnutls_transport_ptr_t)(long) fileno(smtp_in), |
1967 | (gnutls_transport_ptr_t)(long) fileno(smtp_out)); | |
17c76198 PP |
1968 | state->fd_in = fileno(smtp_in); |
1969 | state->fd_out = fileno(smtp_out); | |
059ec3d9 PH |
1970 | |
1971 | sigalrm_seen = FALSE; | |
1972 | if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout); | |
17c76198 | 1973 | do |
17c76198 | 1974 | rc = gnutls_handshake(state->session); |
157a7880 | 1975 | while (rc == GNUTLS_E_AGAIN || rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen); |
059ec3d9 PH |
1976 | alarm(0); |
1977 | ||
17c76198 | 1978 | if (rc != GNUTLS_E_SUCCESS) |
059ec3d9 | 1979 | { |
059ec3d9 PH |
1980 | /* It seems that, except in the case of a timeout, we have to close the |
1981 | connection right here; otherwise if the other end is running OpenSSL it hangs | |
1982 | until the server times out. */ | |
1983 | ||
60d10ce7 | 1984 | if (sigalrm_seen) |
ad7fc6eb | 1985 | { |
cf0c6164 | 1986 | tls_error(US"gnutls_handshake", "timed out", NULL, errstr); |
ad7fc6eb JH |
1987 | gnutls_db_remove_session(state->session); |
1988 | } | |
60d10ce7 | 1989 | else |
059ec3d9 | 1990 | { |
cf0c6164 | 1991 | tls_error(US"gnutls_handshake", gnutls_strerror(rc), NULL, errstr); |
f5d25c2b | 1992 | (void) gnutls_alert_send_appropriate(state->session, rc); |
ad7fc6eb | 1993 | gnutls_deinit(state->session); |
ed62aae3 | 1994 | gnutls_certificate_free_credentials(state->x509_cred); |
60d10ce7 | 1995 | millisleep(500); |
ad7fc6eb | 1996 | shutdown(state->fd_out, SHUT_WR); |
60d10ce7 | 1997 | for (rc = 1024; fgetc(smtp_in) != EOF && rc > 0; ) rc--; /* drain skt */ |
f1e894f3 PH |
1998 | (void)fclose(smtp_out); |
1999 | (void)fclose(smtp_in); | |
60d10ce7 | 2000 | smtp_out = smtp_in = NULL; |
059ec3d9 PH |
2001 | } |
2002 | ||
2003 | return FAIL; | |
2004 | } | |
2005 | ||
2006 | DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n"); | |
2007 | ||
17c76198 PP |
2008 | /* Verify after the fact */ |
2009 | ||
899b8bbc | 2010 | if (!verify_certificate(state, errstr)) |
059ec3d9 | 2011 | { |
9d1c15ef | 2012 | if (state->verify_requirement != VERIFY_OPTIONAL) |
17c76198 | 2013 | { |
cf0c6164 | 2014 | (void) tls_error(US"certificate verification failed", *errstr, NULL, errstr); |
9d1c15ef | 2015 | return FAIL; |
17c76198 | 2016 | } |
9d1c15ef JH |
2017 | DEBUG(D_tls) |
2018 | debug_printf("TLS: continuing on only because verification was optional, after: %s\n", | |
cf0c6164 | 2019 | *errstr); |
059ec3d9 PH |
2020 | } |
2021 | ||
17c76198 PP |
2022 | /* Figure out peer DN, and if authenticated, etc. */ |
2023 | ||
cf0c6164 | 2024 | if ((rc = peer_status(state, NULL)) != OK) return rc; |
17c76198 PP |
2025 | |
2026 | /* Sets various Exim expansion variables; always safe within server */ | |
2027 | ||
9d1c15ef | 2028 | extract_exim_vars_from_tls_state(state); |
059ec3d9 PH |
2029 | |
2030 | /* TLS has been set up. Adjust the input functions to read via TLS, | |
2031 | and initialize appropriately. */ | |
2032 | ||
17c76198 | 2033 | state->xfer_buffer = store_malloc(ssl_xfer_buffer_size); |
059ec3d9 PH |
2034 | |
2035 | receive_getc = tls_getc; | |
0d81dabc | 2036 | receive_getbuf = tls_getbuf; |
584e96c6 | 2037 | receive_get_cache = tls_get_cache; |
059ec3d9 PH |
2038 | receive_ungetc = tls_ungetc; |
2039 | receive_feof = tls_feof; | |
2040 | receive_ferror = tls_ferror; | |
58eb016e | 2041 | receive_smtp_buffered = tls_smtp_buffered; |
059ec3d9 | 2042 | |
059ec3d9 PH |
2043 | return OK; |
2044 | } | |
2045 | ||
2046 | ||
2047 | ||
2048 | ||
aa2a70ba JH |
2049 | static void |
2050 | tls_client_setup_hostname_checks(host_item * host, exim_gnutls_state_st * state, | |
2051 | smtp_transport_options_block * ob) | |
2052 | { | |
5130845b | 2053 | if (verify_check_given_host(&ob->tls_verify_cert_hostnames, host) == OK) |
aa2a70ba | 2054 | { |
4af0d74a | 2055 | state->exp_tls_verify_cert_hostnames = |
8c5d388a | 2056 | #ifdef SUPPORT_I18N |
4af0d74a JH |
2057 | string_domain_utf8_to_alabel(host->name, NULL); |
2058 | #else | |
2059 | host->name; | |
2060 | #endif | |
aa2a70ba JH |
2061 | DEBUG(D_tls) |
2062 | debug_printf("TLS: server cert verification includes hostname: \"%s\".\n", | |
2063 | state->exp_tls_verify_cert_hostnames); | |
2064 | } | |
2065 | } | |
aa2a70ba JH |
2066 | |
2067 | ||
899b8bbc JH |
2068 | |
2069 | ||
2070 | #ifdef SUPPORT_DANE | |
2071 | /* Given our list of RRs from the TLSA lookup, build a lookup block in | |
2072 | GnuTLS-DANE's preferred format. Hang it on the state str for later | |
2073 | use in DANE verification. | |
2074 | ||
2075 | We point at the dnsa data not copy it, so it must remain valid until | |
2076 | after verification is done.*/ | |
2077 | ||
2078 | static void | |
2079 | dane_tlsa_load(exim_gnutls_state_st * state, dns_answer * dnsa) | |
2080 | { | |
2081 | dns_record * rr; | |
2082 | dns_scan dnss; | |
2083 | int i; | |
2084 | const char ** dane_data; | |
2085 | int * dane_data_len; | |
2086 | ||
2087 | for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS), i = 1; | |
2088 | rr; | |
2089 | rr = dns_next_rr(dnsa, &dnss, RESET_NEXT) | |
2090 | ) if (rr->type == T_TLSA) i++; | |
2091 | ||
2092 | dane_data = store_get(i * sizeof(uschar *)); | |
2093 | dane_data_len = store_get(i * sizeof(int)); | |
2094 | ||
2095 | for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS), i = 0; | |
2096 | rr; | |
2097 | rr = dns_next_rr(dnsa, &dnss, RESET_NEXT) | |
2098 | ) if (rr->type == T_TLSA) | |
2099 | { | |
2100 | const uschar * p = rr->data; | |
2101 | uint8_t usage = *p; | |
2102 | ||
2103 | tls_out.tlsa_usage |= 1<<usage; | |
2104 | dane_data[i] = p; | |
2105 | dane_data_len[i++] = rr->size; | |
2106 | } | |
2107 | dane_data[i] = NULL; | |
2108 | dane_data_len[i] = 0; | |
2109 | ||
2110 | state->dane_data = (char * const *)dane_data; | |
2111 | state->dane_data_len = dane_data_len; | |
2112 | } | |
2113 | #endif | |
2114 | ||
2115 | ||
2116 | ||
059ec3d9 PH |
2117 | /************************************************* |
2118 | * Start a TLS session in a client * | |
2119 | *************************************************/ | |
2120 | ||
2121 | /* Called from the smtp transport after STARTTLS has been accepted. | |
2122 | ||
2123 | Arguments: | |
2124 | fd the fd of the connection | |
2125 | host connected host (for messages) | |
83da1223 | 2126 | addr the first address (not used) |
a7538db1 | 2127 | tb transport (always smtp) |
899b8bbc JH |
2128 | tlsa_dnsa non-NULL, either request or require dane for this host, and |
2129 | a TLSA record found. Therefore, dane verify required. | |
2130 | Which implies cert must be requested and supplied, dane | |
2131 | verify must pass, and cert verify irrelevant (incl. | |
2132 | hostnames), and (caller handled) require_tls | |
cf0c6164 JH |
2133 | errstr error string pointer |
2134 | ||
059ec3d9 PH |
2135 | Returns: OK/DEFER/FAIL (because using common functions), |
2136 | but for a client, DEFER and FAIL have the same meaning | |
2137 | */ | |
2138 | ||
2139 | int | |
17c76198 | 2140 | tls_client_start(int fd, host_item *host, |
f5d78688 | 2141 | address_item *addr ARG_UNUSED, |
cf0c6164 | 2142 | transport_instance * tb, |
0e66b3b6 | 2143 | #ifdef EXPERIMENTAL_DANE |
899b8bbc | 2144 | dns_answer * tlsa_dnsa, |
0e66b3b6 | 2145 | #endif |
cf0c6164 | 2146 | uschar ** errstr) |
059ec3d9 | 2147 | { |
a7538db1 JH |
2148 | smtp_transport_options_block *ob = |
2149 | (smtp_transport_options_block *)tb->options_block; | |
059ec3d9 | 2150 | int rc; |
899b8bbc | 2151 | exim_gnutls_state_st * state = NULL; |
f2de3a33 | 2152 | #ifndef DISABLE_OCSP |
5130845b JH |
2153 | BOOL require_ocsp = |
2154 | verify_check_given_host(&ob->hosts_require_ocsp, host) == OK; | |
44662487 | 2155 | BOOL request_ocsp = require_ocsp ? TRUE |
5130845b | 2156 | : verify_check_given_host(&ob->hosts_request_ocsp, host) == OK; |
2b4a568d | 2157 | #endif |
059ec3d9 | 2158 | |
17c76198 | 2159 | DEBUG(D_tls) debug_printf("initialising GnuTLS as a client on fd %d\n", fd); |
059ec3d9 | 2160 | |
65867078 JH |
2161 | if ((rc = tls_init(host, ob->tls_certificate, ob->tls_privatekey, |
2162 | ob->tls_sni, ob->tls_verify_certificates, ob->tls_crl, | |
cf0c6164 | 2163 | ob->tls_require_ciphers, &state, errstr)) != OK) |
2b4a568d | 2164 | return rc; |
059ec3d9 | 2165 | |
54c90be1 | 2166 | { |
65867078 JH |
2167 | int dh_min_bits = ob->tls_dh_min_bits; |
2168 | if (dh_min_bits < EXIM_CLIENT_DH_MIN_MIN_BITS) | |
2169 | { | |
2170 | DEBUG(D_tls) | |
2171 | debug_printf("WARNING: tls_dh_min_bits far too low," | |
2172 | " clamping %d up to %d\n", | |
2173 | dh_min_bits, EXIM_CLIENT_DH_MIN_MIN_BITS); | |
2174 | dh_min_bits = EXIM_CLIENT_DH_MIN_MIN_BITS; | |
2175 | } | |
54c90be1 | 2176 | |
65867078 JH |
2177 | DEBUG(D_tls) debug_printf("Setting D-H prime minimum" |
2178 | " acceptable bits to %d\n", | |
2179 | dh_min_bits); | |
2180 | gnutls_dh_set_prime_bits(state->session, dh_min_bits); | |
2181 | } | |
83da1223 | 2182 | |
94431adb | 2183 | /* Stick to the old behaviour for compatibility if tls_verify_certificates is |
2b4a568d JH |
2184 | set but both tls_verify_hosts and tls_try_verify_hosts are unset. Check only |
2185 | the specified host patterns if one of them is defined */ | |
2186 | ||
899b8bbc JH |
2187 | #ifdef SUPPORT_DANE |
2188 | if (tlsa_dnsa) | |
2189 | { | |
2190 | DEBUG(D_tls) | |
2191 | debug_printf("TLS: server certificate DANE required.\n"); | |
2192 | state->verify_requirement = VERIFY_DANE; | |
2193 | gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE); | |
2194 | dane_tlsa_load(state, tlsa_dnsa); | |
2195 | } | |
2196 | else | |
2197 | #endif | |
2198 | if ( ( state->exp_tls_verify_certificates | |
2199 | && !ob->tls_verify_hosts | |
2200 | && (!ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts) | |
2201 | ) | |
2202 | || verify_check_given_host(&ob->tls_verify_hosts, host) == OK | |
2203 | ) | |
17c76198 | 2204 | { |
aa2a70ba | 2205 | tls_client_setup_hostname_checks(host, state, ob); |
aa2a70ba JH |
2206 | DEBUG(D_tls) |
2207 | debug_printf("TLS: server certificate verification required.\n"); | |
2208 | state->verify_requirement = VERIFY_REQUIRED; | |
52f93eed WB |
2209 | gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE); |
2210 | } | |
5130845b | 2211 | else if (verify_check_given_host(&ob->tls_try_verify_hosts, host) == OK) |
52f93eed | 2212 | { |
aa2a70ba | 2213 | tls_client_setup_hostname_checks(host, state, ob); |
e51c7be2 JH |
2214 | DEBUG(D_tls) |
2215 | debug_printf("TLS: server certificate verification optional.\n"); | |
52f93eed | 2216 | state->verify_requirement = VERIFY_OPTIONAL; |
17c76198 PP |
2217 | gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUEST); |
2218 | } | |
2219 | else | |
2220 | { | |
e51c7be2 JH |
2221 | DEBUG(D_tls) |
2222 | debug_printf("TLS: server certificate verification not required.\n"); | |
52f93eed WB |
2223 | state->verify_requirement = VERIFY_NONE; |
2224 | gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_IGNORE); | |
17c76198 | 2225 | } |
059ec3d9 | 2226 | |
f2de3a33 JH |
2227 | #ifndef DISABLE_OCSP |
2228 | /* supported since GnuTLS 3.1.3 */ | |
44662487 | 2229 | if (request_ocsp) |
9d1c15ef JH |
2230 | { |
2231 | DEBUG(D_tls) debug_printf("TLS: will request OCSP stapling\n"); | |
65867078 JH |
2232 | if ((rc = gnutls_ocsp_status_request_enable_client(state->session, |
2233 | NULL, 0, NULL)) != OK) | |
9d1c15ef | 2234 | return tls_error(US"cert-status-req", |
cf0c6164 | 2235 | gnutls_strerror(rc), state->host, errstr); |
44662487 | 2236 | tls_out.ocsp = OCSP_NOT_RESP; |
9d1c15ef | 2237 | } |
2b4a568d JH |
2238 | #endif |
2239 | ||
0cbf2b82 | 2240 | #ifndef DISABLE_EVENT |
774ef2d7 | 2241 | if (tb->event_action) |
a7538db1 | 2242 | { |
774ef2d7 | 2243 | state->event_action = tb->event_action; |
a7538db1 | 2244 | gnutls_session_set_ptr(state->session, state); |
723fe533 | 2245 | gnutls_certificate_set_verify_function(state->x509_cred, verify_cb); |
a7538db1 JH |
2246 | } |
2247 | #endif | |
2248 | ||
27f19eb4 | 2249 | gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr_t)(long) fd); |
17c76198 PP |
2250 | state->fd_in = fd; |
2251 | state->fd_out = fd; | |
059ec3d9 | 2252 | |
9d1c15ef | 2253 | DEBUG(D_tls) debug_printf("about to gnutls_handshake\n"); |
059ec3d9 PH |
2254 | /* There doesn't seem to be a built-in timeout on connection. */ |
2255 | ||
2256 | sigalrm_seen = FALSE; | |
65867078 | 2257 | alarm(ob->command_timeout); |
17c76198 PP |
2258 | do |
2259 | { | |
2260 | rc = gnutls_handshake(state->session); | |
619b2b25 PP |
2261 | } while ((rc == GNUTLS_E_AGAIN) || |
2262 | (rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen)); | |
059ec3d9 PH |
2263 | alarm(0); |
2264 | ||
4fe99a6c | 2265 | if (rc != GNUTLS_E_SUCCESS) |
60d10ce7 JH |
2266 | if (sigalrm_seen) |
2267 | { | |
2268 | gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_USER_CANCELED); | |
cf0c6164 | 2269 | return tls_error(US"gnutls_handshake", "timed out", state->host, errstr); |
60d10ce7 JH |
2270 | } |
2271 | else | |
cf0c6164 | 2272 | return tls_error(US"gnutls_handshake", gnutls_strerror(rc), state->host, errstr); |
4fe99a6c | 2273 | |
17c76198 | 2274 | DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n"); |
059ec3d9 | 2275 | |
17c76198 | 2276 | /* Verify late */ |
059ec3d9 | 2277 | |
899b8bbc | 2278 | if (!verify_certificate(state, errstr)) |
cf0c6164 | 2279 | return tls_error(US"certificate verification failed", *errstr, state->host, errstr); |
059ec3d9 | 2280 | |
f2de3a33 | 2281 | #ifndef DISABLE_OCSP |
2b4a568d JH |
2282 | if (require_ocsp) |
2283 | { | |
2284 | DEBUG(D_tls) | |
2285 | { | |
2286 | gnutls_datum_t stapling; | |
2287 | gnutls_ocsp_resp_t resp; | |
2288 | gnutls_datum_t printed; | |
2289 | if ( (rc= gnutls_ocsp_status_request_get(state->session, &stapling)) == 0 | |
2290 | && (rc= gnutls_ocsp_resp_init(&resp)) == 0 | |
2291 | && (rc= gnutls_ocsp_resp_import(resp, &stapling)) == 0 | |
2292 | && (rc= gnutls_ocsp_resp_print(resp, GNUTLS_OCSP_PRINT_FULL, &printed)) == 0 | |
2293 | ) | |
2294 | { | |
65867078 | 2295 | debug_printf("%.4096s", printed.data); |
2b4a568d JH |
2296 | gnutls_free(printed.data); |
2297 | } | |
2298 | else | |
cf0c6164 | 2299 | (void) tls_error(US"ocsp decode", gnutls_strerror(rc), state->host, errstr); |
2b4a568d JH |
2300 | } |
2301 | ||
2b4a568d | 2302 | if (gnutls_ocsp_status_request_is_checked(state->session, 0) == 0) |
018058b2 JH |
2303 | { |
2304 | tls_out.ocsp = OCSP_FAILED; | |
cf0c6164 | 2305 | return tls_error(US"certificate status check failed", NULL, state->host, errstr); |
018058b2 | 2306 | } |
2b4a568d | 2307 | DEBUG(D_tls) debug_printf("Passed OCSP checking\n"); |
44662487 | 2308 | tls_out.ocsp = OCSP_VFIED; |
2b4a568d JH |
2309 | } |
2310 | #endif | |
2311 | ||
17c76198 | 2312 | /* Figure out peer DN, and if authenticated, etc. */ |
059ec3d9 | 2313 | |
cf0c6164 | 2314 | if ((rc = peer_status(state, errstr)) != OK) |
2b4a568d | 2315 | return rc; |
059ec3d9 | 2316 | |
4fe99a6c | 2317 | /* Sets various Exim expansion variables; may need to adjust for ACL callouts */ |
059ec3d9 | 2318 | |
9d1c15ef | 2319 | extract_exim_vars_from_tls_state(state); |
059ec3d9 | 2320 | |
059ec3d9 PH |
2321 | return OK; |
2322 | } | |
2323 | ||
2324 | ||
2325 | ||
17c76198 | 2326 | |
059ec3d9 | 2327 | /************************************************* |
17c76198 | 2328 | * Close down a TLS session * |
059ec3d9 PH |
2329 | *************************************************/ |
2330 | ||
17c76198 PP |
2331 | /* This is also called from within a delivery subprocess forked from the |
2332 | daemon, to shut down the TLS library, without actually doing a shutdown (which | |
2333 | would tamper with the TLS session in the parent process). | |
059ec3d9 | 2334 | |
17c76198 PP |
2335 | Arguments: TRUE if gnutls_bye is to be called |
2336 | Returns: nothing | |
059ec3d9 PH |
2337 | */ |
2338 | ||
17c76198 | 2339 | void |
817d9f57 | 2340 | tls_close(BOOL is_server, BOOL shutdown) |
059ec3d9 | 2341 | { |
817d9f57 | 2342 | exim_gnutls_state_st *state = is_server ? &state_server : &state_client; |
059ec3d9 | 2343 | |
389ca47a | 2344 | if (!state->tlsp || state->tlsp->active < 0) return; /* TLS was not active */ |
17c76198 PP |
2345 | |
2346 | if (shutdown) | |
2347 | { | |
f5723109 | 2348 | DEBUG(D_tls) debug_printf("tls_close(): shutting down TLS\n"); |
17c76198 PP |
2349 | gnutls_bye(state->session, GNUTLS_SHUT_WR); |
2350 | } | |
2351 | ||
2352 | gnutls_deinit(state->session); | |
ed62aae3 HSHR |
2353 | gnutls_certificate_free_credentials(state->x509_cred); |
2354 | ||
17c76198 | 2355 | |
389ca47a | 2356 | state->tlsp->active = -1; |
17c76198 PP |
2357 | memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init)); |
2358 | ||
2359 | if ((state_server.session == NULL) && (state_client.session == NULL)) | |
2360 | { | |
2361 | gnutls_global_deinit(); | |
2362 | exim_gnutls_base_init_done = FALSE; | |
2363 | } | |
059ec3d9 PH |
2364 | } |
2365 | ||
2366 | ||
2367 | ||
17c76198 | 2368 | |
0d81dabc JH |
2369 | static BOOL |
2370 | tls_refill(unsigned lim) | |
2371 | { | |
2372 | exim_gnutls_state_st * state = &state_server; | |
2373 | ssize_t inbytes; | |
2374 | ||
2375 | DEBUG(D_tls) debug_printf("Calling gnutls_record_recv(%p, %p, %u)\n", | |
2376 | state->session, state->xfer_buffer, ssl_xfer_buffer_size); | |
2377 | ||
2378 | if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout); | |
2379 | inbytes = gnutls_record_recv(state->session, state->xfer_buffer, | |
2380 | MIN(ssl_xfer_buffer_size, lim)); | |
2381 | alarm(0); | |
2382 | ||
2383 | /* Timeouts do not get this far; see command_timeout_handler(). | |
2384 | A zero-byte return appears to mean that the TLS session has been | |
2385 | closed down, not that the socket itself has been closed down. Revert to | |
2386 | non-TLS handling. */ | |
2387 | ||
2388 | if (sigalrm_seen) | |
2389 | { | |
2390 | DEBUG(D_tls) debug_printf("Got tls read timeout\n"); | |
2391 | state->xfer_error = 1; | |
2392 | return FALSE; | |
2393 | } | |
2394 | ||
2395 | else if (inbytes == 0) | |
2396 | { | |
2397 | DEBUG(D_tls) debug_printf("Got TLS_EOF\n"); | |
2398 | ||
2399 | receive_getc = smtp_getc; | |
2400 | receive_getbuf = smtp_getbuf; | |
2401 | receive_get_cache = smtp_get_cache; | |
2402 | receive_ungetc = smtp_ungetc; | |
2403 | receive_feof = smtp_feof; | |
2404 | receive_ferror = smtp_ferror; | |
2405 | receive_smtp_buffered = smtp_buffered; | |
2406 | ||
2407 | gnutls_deinit(state->session); | |
2408 | gnutls_certificate_free_credentials(state->x509_cred); | |
2409 | ||
2410 | state->session = NULL; | |
2411 | state->tlsp->active = -1; | |
2412 | state->tlsp->bits = 0; | |
2413 | state->tlsp->certificate_verified = FALSE; | |
2414 | tls_channelbinding_b64 = NULL; | |
2415 | state->tlsp->cipher = NULL; | |
2416 | state->tlsp->peercert = NULL; | |
2417 | state->tlsp->peerdn = NULL; | |
2418 | ||
2419 | return FALSE; | |
2420 | } | |
2421 | ||
2422 | /* Handle genuine errors */ | |
2423 | ||
2424 | else if (inbytes < 0) | |
2425 | { | |
2426 | record_io_error(state, (int) inbytes, US"recv", NULL); | |
2427 | state->xfer_error = 1; | |
2428 | return FALSE; | |
2429 | } | |
2430 | #ifndef DISABLE_DKIM | |
2431 | dkim_exim_verify_feed(state->xfer_buffer, inbytes); | |
2432 | #endif | |
2433 | state->xfer_buffer_hwm = (int) inbytes; | |
2434 | state->xfer_buffer_lwm = 0; | |
2435 | return TRUE; | |
2436 | } | |
2437 | ||
059ec3d9 PH |
2438 | /************************************************* |
2439 | * TLS version of getc * | |
2440 | *************************************************/ | |
2441 | ||
2442 | /* This gets the next byte from the TLS input buffer. If the buffer is empty, | |
2443 | it refills the buffer via the GnuTLS reading function. | |
817d9f57 | 2444 | Only used by the server-side TLS. |
059ec3d9 | 2445 | |
17c76198 PP |
2446 | This feeds DKIM and should be used for all message-body reads. |
2447 | ||
bd8fbe36 | 2448 | Arguments: lim Maximum amount to read/bufffer |
059ec3d9 PH |
2449 | Returns: the next character or EOF |
2450 | */ | |
2451 | ||
2452 | int | |
bd8fbe36 | 2453 | tls_getc(unsigned lim) |
059ec3d9 | 2454 | { |
0d81dabc | 2455 | exim_gnutls_state_st * state = &state_server; |
059ec3d9 | 2456 | |
0d81dabc JH |
2457 | if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm) |
2458 | if (!tls_refill(lim)) | |
2459 | return state->xfer_error ? EOF : smtp_getc(lim); | |
ed62aae3 | 2460 | |
0d81dabc | 2461 | /* Something in the buffer; return next uschar */ |
059ec3d9 | 2462 | |
0d81dabc JH |
2463 | return state->xfer_buffer[state->xfer_buffer_lwm++]; |
2464 | } | |
059ec3d9 | 2465 | |
0d81dabc JH |
2466 | uschar * |
2467 | tls_getbuf(unsigned * len) | |
2468 | { | |
2469 | exim_gnutls_state_st * state = &state_server; | |
2470 | unsigned size; | |
2471 | uschar * buf; | |
059ec3d9 | 2472 | |
0d81dabc JH |
2473 | if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm) |
2474 | if (!tls_refill(*len)) | |
059ec3d9 | 2475 | { |
0d81dabc JH |
2476 | if (!state->xfer_error) return smtp_getbuf(len); |
2477 | *len = 0; | |
2478 | return NULL; | |
059ec3d9 | 2479 | } |
059ec3d9 | 2480 | |
0d81dabc JH |
2481 | if ((size = state->xfer_buffer_hwm - state->xfer_buffer_lwm) > *len) |
2482 | size = *len; | |
2483 | buf = &state->xfer_buffer[state->xfer_buffer_lwm]; | |
2484 | state->xfer_buffer_lwm += size; | |
2485 | *len = size; | |
2486 | return buf; | |
059ec3d9 PH |
2487 | } |
2488 | ||
0d81dabc | 2489 | |
584e96c6 JH |
2490 | void |
2491 | tls_get_cache() | |
2492 | { | |
9960d1e5 | 2493 | #ifndef DISABLE_DKIM |
584e96c6 JH |
2494 | exim_gnutls_state_st * state = &state_server; |
2495 | int n = state->xfer_buffer_hwm - state->xfer_buffer_lwm; | |
2496 | if (n > 0) | |
2497 | dkim_exim_verify_feed(state->xfer_buffer+state->xfer_buffer_lwm, n); | |
584e96c6 | 2498 | #endif |
9960d1e5 | 2499 | } |
584e96c6 | 2500 | |
059ec3d9 | 2501 | |
925ac8e4 JH |
2502 | BOOL |
2503 | tls_could_read(void) | |
2504 | { | |
2505 | return state_server.xfer_buffer_lwm < state_server.xfer_buffer_hwm | |
2506 | || gnutls_record_check_pending(state_server.session) > 0; | |
2507 | } | |
2508 | ||
2509 | ||
059ec3d9 | 2510 | |
17c76198 | 2511 | |
059ec3d9 PH |
2512 | /************************************************* |
2513 | * Read bytes from TLS channel * | |
2514 | *************************************************/ | |
2515 | ||
17c76198 PP |
2516 | /* This does not feed DKIM, so if the caller uses this for reading message body, |
2517 | then the caller must feed DKIM. | |
817d9f57 | 2518 | |
059ec3d9 PH |
2519 | Arguments: |
2520 | buff buffer of data | |
2521 | len size of buffer | |
2522 | ||
2523 | Returns: the number of bytes read | |
2524 | -1 after a failed read | |
2525 | */ | |
2526 | ||
2527 | int | |
817d9f57 | 2528 | tls_read(BOOL is_server, uschar *buff, size_t len) |
059ec3d9 | 2529 | { |
817d9f57 | 2530 | exim_gnutls_state_st *state = is_server ? &state_server : &state_client; |
17c76198 | 2531 | ssize_t inbytes; |
059ec3d9 | 2532 | |
17c76198 PP |
2533 | if (len > INT_MAX) |
2534 | len = INT_MAX; | |
059ec3d9 | 2535 | |
17c76198 PP |
2536 | if (state->xfer_buffer_lwm < state->xfer_buffer_hwm) |
2537 | DEBUG(D_tls) | |
2538 | debug_printf("*** PROBABLY A BUG *** " \ | |
2539 | "tls_read() called with data in the tls_getc() buffer, %d ignored\n", | |
2540 | state->xfer_buffer_hwm - state->xfer_buffer_lwm); | |
2541 | ||
2542 | DEBUG(D_tls) | |
2543 | debug_printf("Calling gnutls_record_recv(%p, %p, " SIZE_T_FMT ")\n", | |
2544 | state->session, buff, len); | |
2545 | ||
2546 | inbytes = gnutls_record_recv(state->session, buff, len); | |
059ec3d9 PH |
2547 | if (inbytes > 0) return inbytes; |
2548 | if (inbytes == 0) | |
2549 | { | |
2550 | DEBUG(D_tls) debug_printf("Got TLS_EOF\n"); | |
2551 | } | |
17c76198 | 2552 | else record_io_error(state, (int)inbytes, US"recv", NULL); |
059ec3d9 PH |
2553 | |
2554 | return -1; | |
2555 | } | |
2556 | ||
2557 | ||
2558 | ||
17c76198 | 2559 | |
059ec3d9 PH |
2560 | /************************************************* |
2561 | * Write bytes down TLS channel * | |
2562 | *************************************************/ | |
2563 | ||
2564 | /* | |
2565 | Arguments: | |
817d9f57 | 2566 | is_server channel specifier |
059ec3d9 PH |
2567 | buff buffer of data |
2568 | len number of bytes | |
925ac8e4 | 2569 | more more data expected soon |
059ec3d9 PH |
2570 | |
2571 | Returns: the number of bytes after a successful write, | |
2572 | -1 after a failed write | |
2573 | */ | |
2574 | ||
2575 | int | |
925ac8e4 | 2576 | tls_write(BOOL is_server, const uschar *buff, size_t len, BOOL more) |
059ec3d9 | 2577 | { |
17c76198 PP |
2578 | ssize_t outbytes; |
2579 | size_t left = len; | |
817d9f57 | 2580 | exim_gnutls_state_st *state = is_server ? &state_server : &state_client; |
925ac8e4 JH |
2581 | #ifdef SUPPORT_CORK |
2582 | static BOOL corked = FALSE; | |
2583 | ||
2584 | if (more && !corked) gnutls_record_cork(state->session); | |
2585 | #endif | |
2586 | ||
2587 | DEBUG(D_tls) debug_printf("%s(%p, " SIZE_T_FMT "%s)\n", __FUNCTION__, | |
2588 | buff, left, more ? ", more" : ""); | |
059ec3d9 | 2589 | |
059ec3d9 PH |
2590 | while (left > 0) |
2591 | { | |
17c76198 PP |
2592 | DEBUG(D_tls) debug_printf("gnutls_record_send(SSL, %p, " SIZE_T_FMT ")\n", |
2593 | buff, left); | |
2594 | outbytes = gnutls_record_send(state->session, buff, left); | |
059ec3d9 | 2595 | |
17c76198 | 2596 | DEBUG(D_tls) debug_printf("outbytes=" SSIZE_T_FMT "\n", outbytes); |
059ec3d9 PH |
2597 | if (outbytes < 0) |
2598 | { | |
17c76198 | 2599 | record_io_error(state, outbytes, US"send", NULL); |
059ec3d9 PH |
2600 | return -1; |
2601 | } | |
2602 | if (outbytes == 0) | |
2603 | { | |
17c76198 | 2604 | record_io_error(state, 0, US"send", US"TLS channel closed on write"); |
059ec3d9 PH |
2605 | return -1; |
2606 | } | |
2607 | ||
2608 | left -= outbytes; | |
2609 | buff += outbytes; | |
2610 | } | |
2611 | ||
17c76198 PP |
2612 | if (len > INT_MAX) |
2613 | { | |
2614 | DEBUG(D_tls) | |
2615 | debug_printf("Whoops! Wrote more bytes (" SIZE_T_FMT ") than INT_MAX\n", | |
2616 | len); | |
2617 | len = INT_MAX; | |
2618 | } | |
2619 | ||
925ac8e4 JH |
2620 | #ifdef SUPPORT_CORK |
2621 | if (more != corked) | |
2622 | { | |
2623 | if (!more) (void) gnutls_record_uncork(state->session, 0); | |
2624 | corked = more; | |
2625 | } | |
2626 | #endif | |
2627 | ||
17c76198 | 2628 | return (int) len; |
059ec3d9 PH |
2629 | } |
2630 | ||
2631 | ||
2632 | ||
17c76198 | 2633 | |
059ec3d9 | 2634 | /************************************************* |
17c76198 | 2635 | * Random number generation * |
059ec3d9 PH |
2636 | *************************************************/ |
2637 | ||
17c76198 PP |
2638 | /* Pseudo-random number generation. The result is not expected to be |
2639 | cryptographically strong but not so weak that someone will shoot themselves | |
2640 | in the foot using it as a nonce in input in some email header scheme or | |
2641 | whatever weirdness they'll twist this into. The result should handle fork() | |
2642 | and avoid repeating sequences. OpenSSL handles that for us. | |
059ec3d9 | 2643 | |
17c76198 PP |
2644 | Arguments: |
2645 | max range maximum | |
2646 | Returns a random number in range [0, max-1] | |
059ec3d9 PH |
2647 | */ |
2648 | ||
af3498d6 | 2649 | #ifdef HAVE_GNUTLS_RND |
17c76198 PP |
2650 | int |
2651 | vaguely_random_number(int max) | |
059ec3d9 | 2652 | { |
17c76198 PP |
2653 | unsigned int r; |
2654 | int i, needed_len; | |
2655 | uschar *p; | |
2656 | uschar smallbuf[sizeof(r)]; | |
2657 | ||
2658 | if (max <= 1) | |
2659 | return 0; | |
2660 | ||
2661 | needed_len = sizeof(r); | |
2662 | /* Don't take 8 times more entropy than needed if int is 8 octets and we were | |
2663 | * asked for a number less than 10. */ | |
2664 | for (r = max, i = 0; r; ++i) | |
2665 | r >>= 1; | |
2666 | i = (i + 7) / 8; | |
2667 | if (i < needed_len) | |
2668 | needed_len = i; | |
2669 | ||
2670 | i = gnutls_rnd(GNUTLS_RND_NONCE, smallbuf, needed_len); | |
2671 | if (i < 0) | |
059ec3d9 | 2672 | { |
17c76198 PP |
2673 | DEBUG(D_all) debug_printf("gnutls_rnd() failed, using fallback.\n"); |
2674 | return vaguely_random_number_fallback(max); | |
2675 | } | |
2676 | r = 0; | |
2677 | for (p = smallbuf; needed_len; --needed_len, ++p) | |
2678 | { | |
2679 | r *= 256; | |
2680 | r += *p; | |
059ec3d9 PH |
2681 | } |
2682 | ||
17c76198 PP |
2683 | /* We don't particularly care about weighted results; if someone wants |
2684 | * smooth distribution and cares enough then they should submit a patch then. */ | |
2685 | return r % max; | |
059ec3d9 | 2686 | } |
af3498d6 PP |
2687 | #else /* HAVE_GNUTLS_RND */ |
2688 | int | |
2689 | vaguely_random_number(int max) | |
2690 | { | |
2691 | return vaguely_random_number_fallback(max); | |
2692 | } | |
2693 | #endif /* HAVE_GNUTLS_RND */ | |
059ec3d9 | 2694 | |
36f12725 NM |
2695 | |
2696 | ||
2697 | ||
3375e053 PP |
2698 | /************************************************* |
2699 | * Let tls_require_ciphers be checked at startup * | |
2700 | *************************************************/ | |
2701 | ||
2702 | /* The tls_require_ciphers option, if set, must be something which the | |
2703 | library can parse. | |
2704 | ||
2705 | Returns: NULL on success, or error message | |
2706 | */ | |
2707 | ||
2708 | uschar * | |
2709 | tls_validate_require_cipher(void) | |
2710 | { | |
2711 | int rc; | |
2712 | uschar *expciphers = NULL; | |
2713 | gnutls_priority_t priority_cache; | |
2714 | const char *errpos; | |
cf0c6164 | 2715 | uschar * dummy_errstr; |
3375e053 PP |
2716 | |
2717 | #define validate_check_rc(Label) do { \ | |
2718 | if (rc != GNUTLS_E_SUCCESS) { if (exim_gnutls_base_init_done) gnutls_global_deinit(); \ | |
2719 | return string_sprintf("%s failed: %s", (Label), gnutls_strerror(rc)); } } while (0) | |
2720 | #define return_deinit(Label) do { gnutls_global_deinit(); return (Label); } while (0) | |
2721 | ||
2722 | if (exim_gnutls_base_init_done) | |
2723 | log_write(0, LOG_MAIN|LOG_PANIC, | |
2724 | "already initialised GnuTLS, Exim developer bug"); | |
2725 | ||
a5f239e4 | 2726 | #ifdef HAVE_GNUTLS_PKCS11 |
2519e60d | 2727 | if (!gnutls_allow_auto_pkcs11) |
a5f239e4 PP |
2728 | { |
2729 | rc = gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL); | |
2730 | validate_check_rc(US"gnutls_pkcs11_init"); | |
2731 | } | |
2732 | #endif | |
3375e053 PP |
2733 | rc = gnutls_global_init(); |
2734 | validate_check_rc(US"gnutls_global_init()"); | |
2735 | exim_gnutls_base_init_done = TRUE; | |
2736 | ||
2737 | if (!(tls_require_ciphers && *tls_require_ciphers)) | |
2738 | return_deinit(NULL); | |
2739 | ||
cf0c6164 JH |
2740 | if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers, |
2741 | &dummy_errstr)) | |
3375e053 PP |
2742 | return_deinit(US"failed to expand tls_require_ciphers"); |
2743 | ||
2744 | if (!(expciphers && *expciphers)) | |
2745 | return_deinit(NULL); | |
2746 | ||
2747 | DEBUG(D_tls) | |
2748 | debug_printf("tls_require_ciphers expands to \"%s\"\n", expciphers); | |
2749 | ||
2750 | rc = gnutls_priority_init(&priority_cache, CS expciphers, &errpos); | |
2751 | validate_check_rc(string_sprintf( | |
2752 | "gnutls_priority_init(%s) failed at offset %ld, \"%.8s..\"", | |
2753 | expciphers, errpos - CS expciphers, errpos)); | |
2754 | ||
2755 | #undef return_deinit | |
2756 | #undef validate_check_rc | |
2757 | gnutls_global_deinit(); | |
2758 | ||
2759 | return NULL; | |
2760 | } | |
2761 | ||
2762 | ||
2763 | ||
2764 | ||
36f12725 NM |
2765 | /************************************************* |
2766 | * Report the library versions. * | |
2767 | *************************************************/ | |
2768 | ||
2769 | /* See a description in tls-openssl.c for an explanation of why this exists. | |
2770 | ||
2771 | Arguments: a FILE* to print the results to | |
2772 | Returns: nothing | |
2773 | */ | |
2774 | ||
2775 | void | |
2776 | tls_version_report(FILE *f) | |
2777 | { | |
754a0503 PP |
2778 | fprintf(f, "Library version: GnuTLS: Compile: %s\n" |
2779 | " Runtime: %s\n", | |
2780 | LIBGNUTLS_VERSION, | |
2781 | gnutls_check_version(NULL)); | |
36f12725 NM |
2782 | } |
2783 | ||
2b4a568d JH |
2784 | /* vi: aw ai sw=2 |
2785 | */ | |
059ec3d9 | 2786 | /* End of tls-gnu.c */ |