Docs: add warning on list-sep in headerss_remove
[exim.git] / src / src / tlscert-openssl.c
CommitLineData
9d1c15ef
JH
1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
3386088d 5/* Copyright (c) Jeremy Harris 2014 - 2015 */
9d1c15ef
JH
6
7/* This module provides TLS (aka SSL) support for Exim using the OpenSSL
8library. It is #included into the tls.c file when that library is used.
9*/
10
11
12/* Heading stuff */
13
14#include <openssl/lhash.h>
15#include <openssl/ssl.h>
16#include <openssl/err.h>
17#include <openssl/rand.h>
51424d08 18#include <openssl/x509v3.h>
9d1c15ef
JH
19
20
21/*****************************************************
22* Export/import a certificate, binary/printable
23*****************************************************/
24int
25tls_export_cert(uschar * buf, size_t buflen, void * cert)
26{
27BIO * bp = BIO_new(BIO_s_mem());
28int fail;
29
30if ((fail = PEM_write_bio_X509(bp, (X509 *)cert) ? 0 : 1))
31 log_write(0, LOG_MAIN, "TLS error in certificate export: %s",
32 ERR_error_string(ERR_get_error(), NULL));
33else
34 {
35 char * cp = CS buf;
36 int n;
37 buflen -= 2;
38 for(;;)
39 {
40 if ((n = BIO_gets(bp, cp, (int)buflen)) <= 0) break;
41 cp += n+1;
42 buflen -= n+1;
43 cp[-2] = '\\'; cp[-1] = 'n'; /* newline->"\n" */
44 } /* compat with string_printing() */
45 *cp = '\0';
46 }
47
48BIO_free(bp);
49return fail;
50}
51
52int
53tls_import_cert(const uschar * buf, void ** cert)
54{
55void * reset_point = store_get(0);
56const uschar * cp = string_unprinting(US buf);
57BIO * bp;
58X509 * x;
c03fae8a 59int fail = 0;
9d1c15ef
JH
60
61bp = BIO_new_mem_buf(US cp, -1);
c03fae8a
JH
62if (!(x = PEM_read_bio_X509(bp, NULL, 0, NULL)))
63 {
64 log_write(0, LOG_MAIN, "TLS error in certificate import: %s",
65 ERR_error_string(ERR_get_error(), NULL));
9d1c15ef 66 fail = 1;
c03fae8a 67 }
9d1c15ef
JH
68else
69 *cert = (void *)x;
70BIO_free(bp);
71store_reset(reset_point);
72return fail;
73}
74
75void
76tls_free_cert(void * cert)
77{
78X509_free((X509 *)cert);
79}
80
c03fae8a 81
9d1c15ef
JH
82/*****************************************************
83* Certificate field extraction routines
84*****************************************************/
c03fae8a
JH
85
86/* First, some internal service functions */
87
88static uschar *
89badalloc(void)
90{
91expand_string_message = US"allocation failure";
92return NULL;
93}
94
9d1c15ef
JH
95static uschar *
96bio_string_copy(BIO * bp, int len)
97{
e3dd1d67 98uschar * cp = US"";
9d1c15ef
JH
99len = len > 0 ? (int) BIO_get_mem_data(bp, &cp) : 0;
100cp = string_copyn(cp, len);
101BIO_free(bp);
102return cp;
103}
104
105static uschar *
e9477a08 106asn1_time_copy(const ASN1_TIME * asntime, uschar * mod)
9d1c15ef 107{
e9477a08 108uschar * s = NULL;
9d1c15ef 109BIO * bp = BIO_new(BIO_s_mem());
c03fae8a
JH
110int len;
111
e9477a08
JH
112if (!bp)
113 return badalloc();
114len = ASN1_TIME_print(bp, asntime);
115len = len > 0 ? (int) BIO_get_mem_data(bp, &s) : 0;
c03fae8a 116
e9477a08
JH
117if (mod && Ustrcmp(mod, "raw") == 0) /* native ASN */
118 s = string_copyn(s, len);
119else
120 {
121 struct tm tm;
122 struct tm * tm_p = &tm;
123 BOOL mod_tz;
45500060 124 uschar * tz = to_tz(US"GMT0"); /* need to call strptime with baseline TZ */
e9477a08
JH
125
126 /* Parse OpenSSL ASN1_TIME_print output. A shame there seems to
127 be no other interface for the times.
128 */
129
130 /*XXX %Z might be glibc-specific? Solaris has it, at least*/
131 /*XXX should we switch to POSIX locale for this? */
132 tm.tm_isdst = 0;
133 if (!strptime(CCS s, "%b %e %T %Y %Z", &tm))
134 expand_string_message = US"failed time conversion";
135
136 else
137 {
138 time_t t = mktime(&tm); /* make the tm self-consistent */
139
140 if (mod && Ustrcmp(mod, "int") == 0) /* seconds since epoch */
141 s = string_sprintf("%u", t);
142
143 else
144 {
145 if (!timestamps_utc) /* decoded string in local TZ */
146 { /* shift to local TZ */
147 restore_tz(tz);
148 mod_tz = FALSE;
149 tm_p = localtime(&t);
150 }
151 /* "utc" is default, and rfc5280 says cert times should be Zulu */
152
153 /* convert to string in our format */
154 len = 32;
155 s = store_get(len);
156 strftime(CS s, (size_t)len, "%b %e %T %Y %z", tm_p);
157 }
158 }
159
160 if (mod_tz);
161 restore_tz(tz);
162 }
163BIO_free(bp);
164return s;
9d1c15ef
JH
165}
166
167static uschar *
168x509_name_copy(X509_NAME * name)
169{
170BIO * bp = BIO_new(BIO_s_mem());
c03fae8a
JH
171int len_good;
172
173if (!bp) return badalloc();
174
175len_good =
9d1c15ef
JH
176 X509_NAME_print_ex(bp, name, 0, XN_FLAG_RFC2253) >= 0
177 ? 1 : 0;
178return bio_string_copy(bp, len_good);
179}
180
181/**/
c03fae8a
JH
182/* Now the extractors, called from expand.c
183Arguments:
184 cert The certificate
185 mod Optional modifiers for the operator
186
187Return:
188 Allocated string with extracted value
189*/
9d1c15ef
JH
190
191uschar *
9e4dddbd 192tls_cert_issuer(void * cert, uschar * mod)
9d1c15ef 193{
812a6045
JH
194uschar * cp = x509_name_copy(X509_get_issuer_name((X509 *)cert));
195return mod ? tls_field_from_dn(cp, mod) : cp;
9d1c15ef
JH
196}
197
198uschar *
9e4dddbd 199tls_cert_not_before(void * cert, uschar * mod)
9d1c15ef 200{
25ba2544 201return asn1_time_copy(X509_get_notBefore((X509 *)cert), mod);
9d1c15ef
JH
202}
203
204uschar *
9e4dddbd 205tls_cert_not_after(void * cert, uschar * mod)
9d1c15ef 206{
25ba2544 207return asn1_time_copy(X509_get_notAfter((X509 *)cert), mod);
9d1c15ef
JH
208}
209
210uschar *
9e4dddbd 211tls_cert_serial_number(void * cert, uschar * mod)
9d1c15ef
JH
212{
213uschar txt[256];
214BIO * bp = BIO_new(BIO_s_mem());
c03fae8a 215int len;
9d1c15ef 216
c03fae8a
JH
217if (!bp) return badalloc();
218
219len = i2a_ASN1_INTEGER(bp, X509_get_serialNumber((X509 *)cert));
9d1c15ef
JH
220if (len < sizeof(txt))
221 BIO_read(bp, txt, len);
222else
223 len = 0;
224BIO_free(bp);
225return string_copynlc(txt, len); /* lowercase */
226}
227
228uschar *
9e4dddbd 229tls_cert_signature(void * cert, uschar * mod)
9d1c15ef 230{
9d1c15ef 231uschar * cp = NULL;
c03fae8a
JH
232BIO * bp = BIO_new(BIO_s_mem());
233
234if (!bp) return badalloc();
9d1c15ef
JH
235
236if (X509_print_ex(bp, (X509 *)cert, 0,
237 X509_FLAG_NO_HEADER | X509_FLAG_NO_VERSION | X509_FLAG_NO_SERIAL |
238 X509_FLAG_NO_SIGNAME | X509_FLAG_NO_ISSUER | X509_FLAG_NO_VALIDITY |
239 X509_FLAG_NO_SUBJECT | X509_FLAG_NO_PUBKEY | X509_FLAG_NO_EXTENSIONS |
240 /* X509_FLAG_NO_SIGDUMP is the missing one */
241 X509_FLAG_NO_AUX) == 1)
242 {
243 long len = BIO_get_mem_data(bp, &cp);
315e209a
JH
244
245 /* Strip leading "Signature Algorithm" line */
246 while (*cp && *cp != '\n') { cp++; len--; }
247
248 cp = string_copyn(cp+1, len-1);
9d1c15ef
JH
249 }
250BIO_free(bp);
251return cp;
252}
253
254uschar *
9e4dddbd 255tls_cert_signature_algorithm(void * cert, uschar * mod)
9d1c15ef 256{
315e209a
JH
257uschar * cp = NULL;
258BIO * bp = BIO_new(BIO_s_mem());
259
260if (!bp) return badalloc();
261
262if (X509_print_ex(bp, (X509 *)cert, 0,
263 X509_FLAG_NO_HEADER | X509_FLAG_NO_VERSION | X509_FLAG_NO_SERIAL |
264 /* X509_FLAG_NO_SIGNAME is the missing one */
265 X509_FLAG_NO_ISSUER | X509_FLAG_NO_VALIDITY |
266 X509_FLAG_NO_SUBJECT | X509_FLAG_NO_PUBKEY | X509_FLAG_NO_EXTENSIONS |
267 X509_FLAG_NO_SIGDUMP | X509_FLAG_NO_AUX) == 1)
268 {
269 long len = BIO_get_mem_data(bp, &cp);
270
271 /* Strip leading " Signature Algorithm: " and trailing newline */
272 while (*cp && *cp != ':') { cp++; len--; }
273 do { cp++; len--; } while (*cp && *cp == ' ');
274 if (cp[len-1] == '\n') len--;
275
276 cp = string_copyn(cp, len);
277 }
278BIO_free(bp);
279return cp;
9d1c15ef
JH
280}
281
282uschar *
9e4dddbd 283tls_cert_subject(void * cert, uschar * mod)
9d1c15ef 284{
812a6045
JH
285uschar * cp = x509_name_copy(X509_get_subject_name((X509 *)cert));
286return mod ? tls_field_from_dn(cp, mod) : cp;
9d1c15ef
JH
287}
288
289uschar *
9e4dddbd 290tls_cert_version(void * cert, uschar * mod)
9d1c15ef
JH
291{
292return string_sprintf("%d", X509_get_version((X509 *)cert));
293}
294
295uschar *
296tls_cert_ext_by_oid(void * cert, uschar * oid, int idx)
297{
e3dd1d67 298int nid = OBJ_create(CS oid, "", "");
9d1c15ef
JH
299int nidx = X509_get_ext_by_NID((X509 *)cert, nid, idx);
300X509_EXTENSION * ex = X509_get_ext((X509 *)cert, nidx);
301ASN1_OCTET_STRING * adata = X509_EXTENSION_get_data(ex);
302BIO * bp = BIO_new(BIO_s_mem());
303long len;
304uschar * cp1;
305uschar * cp2;
306uschar * cp3;
307
c03fae8a
JH
308if (!bp) return badalloc();
309
9d1c15ef
JH
310M_ASN1_OCTET_STRING_print(bp, adata);
311/* binary data, DER encoded */
312
313/* just dump for now */
314len = BIO_get_mem_data(bp, &cp1);
315cp3 = cp2 = store_get(len*3+1);
316
317while(len)
318 {
e3dd1d67 319 sprintf(CS cp2, "%.2x ", *cp1++);
9d1c15ef
JH
320 cp2 += 3;
321 len--;
322 }
323cp2[-1] = '\0';
324
325return cp3;
326}
327
328uschar *
9e4dddbd 329tls_cert_subject_altname(void * cert, uschar * mod)
9d1c15ef 330{
9e4dddbd 331uschar * list = NULL;
9d1c15ef
JH
332STACK_OF(GENERAL_NAME) * san = (STACK_OF(GENERAL_NAME) *)
333 X509_get_ext_d2i((X509 *)cert, NID_subject_alt_name, NULL, NULL);
b3ef41c9 334uschar osep = '\n';
9e4dddbd
JH
335uschar * tag = US"";
336uschar * ele;
337int match = -1;
e51c7be2 338int len;
9d1c15ef
JH
339
340if (!san) return NULL;
341
b3ef41c9 342while (mod && *mod)
9e4dddbd 343 {
b3ef41c9
JH
344 if (*mod == '>' && *++mod) osep = *mod++;
345 else if (Ustrncmp(mod,"dns",3)==0) { match = GEN_DNS; mod += 3; }
346 else if (Ustrncmp(mod,"uri",3)==0) { match = GEN_URI; mod += 3; }
347 else if (Ustrncmp(mod,"mail",4)==0) { match = GEN_EMAIL; mod += 4; }
348 else mod++;
9e4dddbd 349
b3ef41c9 350 if (*mod == ',') mod++;
9e4dddbd
JH
351 }
352
9d1c15ef
JH
353while (sk_GENERAL_NAME_num(san) > 0)
354 {
355 GENERAL_NAME * namePart = sk_GENERAL_NAME_pop(san);
9e4dddbd
JH
356 if (match != -1 && match != namePart->type)
357 continue;
9d1c15ef
JH
358 switch (namePart->type)
359 {
9e4dddbd
JH
360 case GEN_DNS:
361 tag = US"DNS";
362 ele = ASN1_STRING_data(namePart->d.dNSName);
e51c7be2 363 len = ASN1_STRING_length(namePart->d.dNSName);
9e4dddbd 364 break;
9d1c15ef 365 case GEN_URI:
9e4dddbd
JH
366 tag = US"URI";
367 ele = ASN1_STRING_data(namePart->d.uniformResourceIdentifier);
e51c7be2 368 len = ASN1_STRING_length(namePart->d.uniformResourceIdentifier);
9e4dddbd 369 break;
9d1c15ef 370 case GEN_EMAIL:
9e4dddbd
JH
371 tag = US"MAIL";
372 ele = ASN1_STRING_data(namePart->d.rfc822Name);
e51c7be2 373 len = ASN1_STRING_length(namePart->d.rfc822Name);
9e4dddbd 374 break;
9d1c15ef 375 default:
9e4dddbd 376 continue; /* ignore unrecognised types */
9d1c15ef 377 }
e51c7be2
JH
378 if (ele[len]) /* not nul-terminated */
379 ele = string_copyn(ele, len);
380
9acf6b94 381 if (Ustrlen(ele) == len) /* ignore any with embedded nul */
b3ef41c9 382 list = string_append_listele(list, osep,
9e4dddbd 383 match == -1 ? string_sprintf("%s=%s", tag, ele) : ele);
9d1c15ef
JH
384 }
385
9e4dddbd
JH
386sk_GENERAL_NAME_free(san);
387return list;
9d1c15ef
JH
388}
389
390uschar *
9e4dddbd 391tls_cert_ocsp_uri(void * cert, uschar * mod)
9d1c15ef
JH
392{
393STACK_OF(ACCESS_DESCRIPTION) * ads = (STACK_OF(ACCESS_DESCRIPTION) *)
394 X509_get_ext_d2i((X509 *)cert, NID_info_access, NULL, NULL);
395int adsnum = sk_ACCESS_DESCRIPTION_num(ads);
396int i;
9e4dddbd
JH
397uschar sep = '\n';
398uschar * list = NULL;
399
400if (mod)
401 if (*mod == '>' && *++mod) sep = *mod++;
9d1c15ef
JH
402
403for (i = 0; i < adsnum; i++)
404 {
405 ACCESS_DESCRIPTION * ad = sk_ACCESS_DESCRIPTION_value(ads, i);
406
407 if (ad && OBJ_obj2nid(ad->method) == NID_ad_OCSP)
00ba27c5
JH
408 {
409 uschar * ele = ASN1_STRING_data(ad->location->d.ia5);
410 int len = ASN1_STRING_length(ad->location->d.ia5);
411 list = string_append_listele_n(list, sep, ele, len);
412 }
9d1c15ef 413 }
00ba27c5 414sk_ACCESS_DESCRIPTION_free(ads);
9e4dddbd 415return list;
9d1c15ef
JH
416}
417
418uschar *
9e4dddbd 419tls_cert_crl_uri(void * cert, uschar * mod)
9d1c15ef
JH
420{
421STACK_OF(DIST_POINT) * dps = (STACK_OF(DIST_POINT) *)
422 X509_get_ext_d2i((X509 *)cert, NID_crl_distribution_points,
423 NULL, NULL);
424DIST_POINT * dp;
425int dpsnum = sk_DIST_POINT_num(dps);
426int i;
9e4dddbd
JH
427uschar sep = '\n';
428uschar * list = NULL;
429
430if (mod)
431 if (*mod == '>' && *++mod) sep = *mod++;
9d1c15ef
JH
432
433if (dps) for (i = 0; i < dpsnum; i++)
434 if ((dp = sk_DIST_POINT_value(dps, i)))
435 {
436 STACK_OF(GENERAL_NAME) * names = dp->distpoint->name.fullname;
437 GENERAL_NAME * np;
438 int nnum = sk_GENERAL_NAME_num(names);
439 int j;
440
441 for (j = 0; j < nnum; j++)
442 if ( (np = sk_GENERAL_NAME_value(names, j))
443 && np->type == GEN_URI
444 )
00ba27c5
JH
445 {
446 uschar * ele = ASN1_STRING_data(np->d.uniformResourceIdentifier);
447 int len = ASN1_STRING_length(np->d.uniformResourceIdentifier);
448 list = string_append_listele_n(list, sep, ele, len);
449 }
9d1c15ef 450 }
00ba27c5 451sk_DIST_POINT_free(dps);
9e4dddbd 452return list;
9d1c15ef
JH
453}
454
6a8a60e0
JH
455
456
457/*****************************************************
458* Certificate operator routines
459*****************************************************/
460static uschar *
461fingerprint(X509 * cert, const EVP_MD * fdig)
462{
463int j;
464unsigned int n;
465uschar md[EVP_MAX_MD_SIZE];
466uschar * cp;
467
468if (!X509_digest(cert,fdig,md,&n))
469 {
470 expand_string_message = US"tls_cert_fprt: out of mem\n";
471 return NULL;
472 }
473cp = store_get(n*2+1);
e3dd1d67 474for (j = 0; j < (int)n; j++) sprintf(CS cp+2*j, "%02X", md[j]);
6a8a60e0
JH
475return(cp);
476}
477
478uschar *
479tls_cert_fprt_md5(void * cert)
480{
481return fingerprint((X509 *)cert, EVP_md5());
482}
483
484uschar *
485tls_cert_fprt_sha1(void * cert)
486{
487return fingerprint((X509 *)cert, EVP_sha1());
488}
489
9ef9101c
JH
490uschar *
491tls_cert_fprt_sha256(void * cert)
492{
493return fingerprint((X509 *)cert, EVP_sha256());
494}
495
6a8a60e0 496
9d1c15ef
JH
497/* vi: aw ai sw=2
498*/
499/* End of tlscert-openssl.c */