1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) Jeremy Harris 2014 */
7 /* This file provides TLS/SSL support for Exim using the GnuTLS library,
8 one of the available supported implementations. This file is #included into
9 tls.c when USE_GNUTLS has been set.
12 #include <gnutls/gnutls.h>
13 /* needed for cert checks in verification and DN extraction: */
14 #include <gnutls/x509.h>
15 /* needed to disable PKCS11 autoload unless requested */
16 #if GNUTLS_VERSION_NUMBER >= 0x020c00
17 # include <gnutls/pkcs11.h>
21 /*****************************************************
22 * Export/import a certificate, binary/printable
23 *****************************************************/
25 tls_export_cert(uschar
* buf
, size_t buflen
, void * cert
)
28 void * reset_point
= store_get(0);
32 if ((fail
= gnutls_x509_crt_export((gnutls_x509_crt_t
)cert
,
33 GNUTLS_X509_FMT_PEM
, buf
, &sz
)))
35 log_write(0, LOG_MAIN
, "TLS error in certificate export: %s",
36 gnutls_strerror(fail
));
39 if ((cp
= string_printing(buf
)) != buf
)
41 Ustrncpy(buf
, cp
, buflen
);
45 store_reset(reset_point
);
50 tls_import_cert(const uschar
* buf
, void ** cert
)
52 void * reset_point
= store_get(0);
54 gnutls_x509_crt_t crt
;
58 gnutls_x509_crt_init(&crt
);
60 datum
.data
= string_unprinting(US buf
);
61 datum
.size
= Ustrlen(datum
.data
);
62 if ((fail
= gnutls_x509_crt_import(crt
, &datum
, GNUTLS_X509_FMT_PEM
)))
64 log_write(0, LOG_MAIN
, "TLS error in certificate import: %s",
65 gnutls_strerror(fail
));
71 store_reset(reset_point
);
76 tls_free_cert(void * cert
)
78 gnutls_x509_crt_deinit((gnutls_x509_crt_t
) cert
);
79 gnutls_global_deinit();
82 /*****************************************************
83 * Certificate field extraction routines
84 *****************************************************/
86 /* First, some internal service functions */
89 g_err(const char * tag
, const char * from
, int gnutls_err
)
91 expand_string_message
= string_sprintf("%s: %s fail: %s\n",
92 from
, tag
, gnutls_strerror(gnutls_err
));
98 time_copy(time_t t
, uschar
* mod
)
103 if (mod
&& Ustrcmp(mod
, "int") == 0)
104 return string_sprintf("%u", (unsigned)t
);
109 uschar
* tz
= to_tz(US
"GMT0");
110 len
= strftime(CS cp
, len
, "%b %e %T %Y %Z", gmtime(&t
));
114 len
= strftime(CS cp
, len
, "%b %e %T %Y %Z", localtime(&t
));
115 return len
> 0 ? cp
: NULL
;
120 /* Now the extractors, called from expand.c
123 mod Optional modifiers for the operator
126 Allocated string with extracted value
130 tls_cert_issuer(void * cert
, uschar
* mod
)
136 if ((ret
= gnutls_x509_crt_get_issuer_dn(cert
, cp
, &siz
))
137 != GNUTLS_E_SHORT_MEMORY_BUFFER
)
138 return g_err("gi0", __FUNCTION__
, ret
);
141 if ((ret
= gnutls_x509_crt_get_issuer_dn(cert
, cp
, &siz
)) < 0)
142 return g_err("gi1", __FUNCTION__
, ret
);
144 return mod
? tls_field_from_dn(cp
, mod
) : cp
;
148 tls_cert_not_after(void * cert
, uschar
* mod
)
151 gnutls_x509_crt_get_expiration_time((gnutls_x509_crt_t
)cert
),
156 tls_cert_not_before(void * cert
, uschar
* mod
)
159 gnutls_x509_crt_get_activation_time((gnutls_x509_crt_t
)cert
),
164 tls_cert_serial_number(void * cert
, uschar
* mod
)
166 uschar bin
[50], txt
[150];
167 size_t sz
= sizeof(bin
);
172 if ((ret
= gnutls_x509_crt_get_serial((gnutls_x509_crt_t
)cert
,
174 return g_err("gs0", __FUNCTION__
, ret
);
176 for(dp
= txt
, sp
= bin
; sz
; dp
+= 2, sp
++, sz
--)
177 sprintf(dp
, "%.2x", *sp
);
178 for(sp
= txt
; sp
[0]=='0' && sp
[1]; ) sp
++; /* leading zeroes */
179 return string_copy(sp
);
183 tls_cert_signature(void * cert
, uschar
* mod
)
191 if ((ret
= gnutls_x509_crt_get_signature((gnutls_x509_crt_t
)cert
, cp1
, &len
))
192 != GNUTLS_E_SHORT_MEMORY_BUFFER
)
193 return g_err("gs0", __FUNCTION__
, ret
);
195 cp1
= store_get(len
*4+1);
196 if (gnutls_x509_crt_get_signature((gnutls_x509_crt_t
)cert
, cp1
, &len
) != 0)
197 return g_err("gs1", __FUNCTION__
, ret
);
199 for(cp3
= cp2
= cp1
+len
; cp1
< cp2
; cp3
+= 3, cp1
++)
200 sprintf(cp3
, "%.2x ", *cp1
);
207 tls_cert_signature_algorithm(void * cert
, uschar
* mod
)
209 gnutls_sign_algorithm_t algo
=
210 gnutls_x509_crt_get_signature_algorithm((gnutls_x509_crt_t
)cert
);
211 return algo
< 0 ? NULL
: string_copy(gnutls_sign_get_name(algo
));
215 tls_cert_subject(void * cert
, uschar
* mod
)
221 if ((ret
= gnutls_x509_crt_get_dn(cert
, cp
, &siz
))
222 != GNUTLS_E_SHORT_MEMORY_BUFFER
)
223 return g_err("gs0", __FUNCTION__
, ret
);
226 if ((ret
= gnutls_x509_crt_get_dn(cert
, cp
, &siz
)) < 0)
227 return g_err("gs1", __FUNCTION__
, ret
);
229 return mod
? tls_field_from_dn(cp
, mod
) : cp
;
233 tls_cert_version(void * cert
, uschar
* mod
)
235 return string_sprintf("%d", gnutls_x509_crt_get_version(cert
));
239 tls_cert_ext_by_oid(void * cert
, uschar
* oid
, int idx
)
248 ret
= gnutls_x509_crt_get_extension_by_oid ((gnutls_x509_crt_t
)cert
,
249 oid
, idx
, cp1
, &siz
, &crit
);
250 if (ret
!= GNUTLS_E_SHORT_MEMORY_BUFFER
)
251 return g_err("ge0", __FUNCTION__
, ret
);
253 cp1
= store_get(siz
*4 + 1);
255 ret
= gnutls_x509_crt_get_extension_by_oid ((gnutls_x509_crt_t
)cert
,
256 oid
, idx
, cp1
, &siz
, &crit
);
258 return g_err("ge1", __FUNCTION__
, ret
);
260 /* binary data, DER encoded */
262 /* just dump for now */
263 for(cp3
= cp2
= cp1
+siz
; cp1
< cp2
; cp3
+= 3, cp1
++)
264 sprintf(cp3
, "%.2x ", *cp1
);
271 tls_cert_subject_altname(void * cert
, uschar
* mod
)
273 uschar
* list
= NULL
;
284 if (*mod
== '>' && *++mod
) sep
= *mod
++;
285 else if (Ustrcmp(mod
, "dns")==0) { match
= GNUTLS_SAN_DNSNAME
; mod
+= 3; }
286 else if (Ustrcmp(mod
, "uri")==0) { match
= GNUTLS_SAN_URI
; mod
+= 3; }
287 else if (Ustrcmp(mod
, "mail")==0) { match
= GNUTLS_SAN_RFC822NAME
; mod
+= 4; }
294 for(index
= 0;; index
++)
297 switch(ret
= gnutls_x509_crt_get_subject_alt_name(
298 (gnutls_x509_crt_t
)cert
, index
, NULL
, &siz
, NULL
))
300 case GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE
:
301 return list
; /* no more elements; normal exit */
303 case GNUTLS_E_SHORT_MEMORY_BUFFER
:
307 return g_err("gs0", __FUNCTION__
, ret
);
310 ele
= store_get(siz
+1);
311 if ((ret
= gnutls_x509_crt_get_subject_alt_name(
312 (gnutls_x509_crt_t
)cert
, index
, ele
, &siz
, NULL
)) < 0)
313 return g_err("gs1", __FUNCTION__
, ret
);
316 if ( match
!= -1 && match
!= ret
/* wrong type of SAN */
317 || Ustrlen(ele
) != siz
) /* contains a NUL */
321 case GNUTLS_SAN_DNSNAME
: tag
= US
"DNS"; break;
322 case GNUTLS_SAN_URI
: tag
= US
"URI"; break;
323 case GNUTLS_SAN_RFC822NAME
: tag
= US
"MAIL"; break;
324 default: continue; /* ignore unrecognised types */
326 list
= string_append_listele(list
, sep
,
327 match
== -1 ? string_sprintf("%s=%s", tag
, ele
) : ele
);
333 tls_cert_ocsp_uri(void * cert
, uschar
* mod
)
335 #if GNUTLS_VERSION_NUMBER >= 0x030000
340 uschar
* list
= NULL
;
343 if (*mod
== '>' && *++mod
) sep
= *mod
++;
345 for(index
= 0;; index
++)
347 ret
= gnutls_x509_crt_get_authority_info_access((gnutls_x509_crt_t
)cert
,
348 index
, GNUTLS_IA_OCSP_URI
, &uri
, NULL
);
350 if (ret
== GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE
)
353 return g_err("gai", __FUNCTION__
, ret
);
355 list
= string_append_listele(list
, sep
,
356 string_copyn(uri
.data
, uri
.size
));
362 expand_string_message
=
363 string_sprintf("%s: OCSP support with GnuTLS requires version 3.0.0\n",
371 tls_cert_crl_uri(void * cert
, uschar
* mod
)
377 uschar
* list
= NULL
;
381 if (*mod
== '>' && *++mod
) sep
= *mod
++;
383 for(index
= 0;; index
++)
386 switch(ret
= gnutls_x509_crt_get_crl_dist_points(
387 (gnutls_x509_crt_t
)cert
, index
, NULL
, &siz
, NULL
, NULL
))
389 case GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE
:
391 case GNUTLS_E_SHORT_MEMORY_BUFFER
:
394 return g_err("gc0", __FUNCTION__
, ret
);
397 ele
= store_get(siz
+1);
398 if ((ret
= gnutls_x509_crt_get_crl_dist_points(
399 (gnutls_x509_crt_t
)cert
, index
, ele
, &siz
, NULL
, NULL
)) < 0)
400 return g_err("gc1", __FUNCTION__
, ret
);
403 list
= string_append_listele(list
, sep
, ele
);
409 /*****************************************************
410 * Certificate operator routines
411 *****************************************************/
413 fingerprint(gnutls_x509_crt_t cert
, gnutls_digest_algorithm_t algo
)
421 if ((ret
= gnutls_x509_crt_get_fingerprint(cert
, algo
, NULL
, &siz
))
422 != GNUTLS_E_SHORT_MEMORY_BUFFER
)
423 return g_err("gf0", __FUNCTION__
, ret
);
425 cp
= store_get(siz
*3+1);
426 if ((ret
= gnutls_x509_crt_get_fingerprint(cert
, algo
, cp
, &siz
)) < 0)
427 return g_err("gf1", __FUNCTION__
, ret
);
429 for (cp3
= cp2
= cp
+siz
; cp
< cp2
; cp
++, cp3
+=2)
430 sprintf(cp3
, "%02X",*cp
);
436 tls_cert_fprt_md5(void * cert
)
438 return fingerprint((gnutls_x509_crt_t
)cert
, GNUTLS_DIG_MD5
);
442 tls_cert_fprt_sha1(void * cert
)
444 return fingerprint((gnutls_x509_crt_t
)cert
, GNUTLS_DIG_SHA1
);
448 tls_cert_fprt_sha256(void * cert
)
450 return fingerprint((gnutls_x509_crt_t
)cert
, GNUTLS_DIG_SHA256
);
456 /* End of tlscert-gnu.c */