1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) Jeremy Harris 2014 */
7 /* This module provides TLS (aka SSL) support for Exim using the OpenSSL
8 library. It is #included into the tls.c file when that library is used.
14 #include <openssl/lhash.h>
15 #include <openssl/ssl.h>
16 #include <openssl/err.h>
17 #include <openssl/rand.h>
18 #include <openssl/x509v3.h>
21 /*****************************************************
22 * Export/import a certificate, binary/printable
23 *****************************************************/
25 tls_export_cert(uschar * buf, size_t buflen, void * cert)
27 BIO * bp = BIO_new(BIO_s_mem());
30 if ((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));
40 if ((n = BIO_gets(bp, cp, (int)buflen)) <= 0) break;
43 cp[-2] = '\\'; cp[-1] = 'n'; /* newline->"\n" */
44 } /* compat with string_printing() */
53 tls_import_cert(const uschar * buf, void ** cert)
55 void * reset_point = store_get(0);
56 const uschar * cp = string_unprinting(US buf);
60 bp = BIO_new_mem_buf(US cp, -1);
61 x = PEM_read_bio_X509(bp, NULL, 0, NULL);
68 store_reset(reset_point);
73 tls_free_cert(void * cert)
75 X509_free((X509 *)cert);
78 /*****************************************************
79 * Certificate field extraction routines
80 *****************************************************/
82 bio_string_copy(BIO * bp, int len)
85 len = len > 0 ? (int) BIO_get_mem_data(bp, &cp) : 0;
86 cp = string_copyn(cp, len);
92 asn1_time_copy(const ASN1_TIME * time)
94 BIO * bp = BIO_new(BIO_s_mem());
95 int len = ASN1_TIME_print(bp, time);
96 return bio_string_copy(bp, len);
100 x509_name_copy(X509_NAME * name)
102 BIO * bp = BIO_new(BIO_s_mem());
104 X509_NAME_print_ex(bp, name, 0, XN_FLAG_RFC2253) >= 0
106 return bio_string_copy(bp, len_good);
112 tls_cert_issuer(void * cert, uschar * mod)
114 return x509_name_copy(X509_get_issuer_name((X509 *)cert));
118 tls_cert_not_before(void * cert, uschar * mod)
120 return asn1_time_copy(X509_get_notBefore((X509 *)cert));
124 tls_cert_not_after(void * cert, uschar * mod)
126 return asn1_time_copy(X509_get_notAfter((X509 *)cert));
130 tls_cert_serial_number(void * cert, uschar * mod)
133 BIO * bp = BIO_new(BIO_s_mem());
134 int len = i2a_ASN1_INTEGER(bp, X509_get_serialNumber((X509 *)cert));
136 if (len < sizeof(txt))
137 BIO_read(bp, txt, len);
141 return string_copynlc(txt, len); /* lowercase */
145 tls_cert_signature(void * cert, uschar * mod)
147 BIO * bp = BIO_new(BIO_s_mem());
150 if (X509_print_ex(bp, (X509 *)cert, 0,
151 X509_FLAG_NO_HEADER | X509_FLAG_NO_VERSION | X509_FLAG_NO_SERIAL |
152 X509_FLAG_NO_SIGNAME | X509_FLAG_NO_ISSUER | X509_FLAG_NO_VALIDITY |
153 X509_FLAG_NO_SUBJECT | X509_FLAG_NO_PUBKEY | X509_FLAG_NO_EXTENSIONS |
154 /* X509_FLAG_NO_SIGDUMP is the missing one */
155 X509_FLAG_NO_AUX) == 1)
157 long len = BIO_get_mem_data(bp, &cp);
158 cp = string_copyn(cp, len);
165 tls_cert_signature_algorithm(void * cert, uschar * mod)
167 return string_copy(OBJ_nid2ln(X509_get_signature_type((X509 *)cert)));
171 tls_cert_subject(void * cert, uschar * mod)
173 return x509_name_copy(X509_get_subject_name((X509 *)cert));
177 tls_cert_version(void * cert, uschar * mod)
179 return string_sprintf("%d", X509_get_version((X509 *)cert));
183 tls_cert_ext_by_oid(void * cert, uschar * oid, int idx)
185 int nid = OBJ_create(oid, "", "");
186 int nidx = X509_get_ext_by_NID((X509 *)cert, nid, idx);
187 X509_EXTENSION * ex = X509_get_ext((X509 *)cert, nidx);
188 ASN1_OCTET_STRING * adata = X509_EXTENSION_get_data(ex);
189 BIO * bp = BIO_new(BIO_s_mem());
195 M_ASN1_OCTET_STRING_print(bp, adata);
196 /* binary data, DER encoded */
198 /* just dump for now */
199 len = BIO_get_mem_data(bp, &cp1);
200 cp3 = cp2 = store_get(len*3+1);
204 sprintf(cp2, "%.2x ", *cp1++);
214 tls_cert_subject_altname(void * cert, uschar * mod)
216 uschar * list = NULL;
217 STACK_OF(GENERAL_NAME) * san = (STACK_OF(GENERAL_NAME) *)
218 X509_get_ext_d2i((X509 *)cert, NID_subject_alt_name, NULL, NULL);
224 if (!san) return NULL;
228 if (*mod == '>' && *++mod) sep = *mod++;
229 else if (Ustrcmp(mod, "dns")==0) { match = GEN_DNS; mod += 3; }
230 else if (Ustrcmp(mod, "uri")==0) { match = GEN_URI; mod += 3; }
231 else if (Ustrcmp(mod, "mail")==0) { match = GEN_EMAIL; mod += 4; }
238 while (sk_GENERAL_NAME_num(san) > 0)
240 GENERAL_NAME * namePart = sk_GENERAL_NAME_pop(san);
241 if (match != -1 && match != namePart->type)
243 switch (namePart->type)
247 ele = ASN1_STRING_data(namePart->d.dNSName);
251 ele = ASN1_STRING_data(namePart->d.uniformResourceIdentifier);
255 ele = ASN1_STRING_data(namePart->d.rfc822Name);
258 continue; /* ignore unrecognised types */
260 list = string_append_listele(list, sep,
261 match == -1 ? string_sprintf("%s=%s", tag, ele) : ele);
264 sk_GENERAL_NAME_free(san);
269 tls_cert_ocsp_uri(void * cert, uschar * mod)
271 STACK_OF(ACCESS_DESCRIPTION) * ads = (STACK_OF(ACCESS_DESCRIPTION) *)
272 X509_get_ext_d2i((X509 *)cert, NID_info_access, NULL, NULL);
273 int adsnum = sk_ACCESS_DESCRIPTION_num(ads);
276 uschar * list = NULL;
279 if (*mod == '>' && *++mod) sep = *mod++;
281 for (i = 0; i < adsnum; i++)
283 ACCESS_DESCRIPTION * ad = sk_ACCESS_DESCRIPTION_value(ads, i);
285 if (ad && OBJ_obj2nid(ad->method) == NID_ad_OCSP)
286 list = string_append_listele(list, sep,
287 ASN1_STRING_data(ad->location->d.ia5));
293 tls_cert_crl_uri(void * cert, uschar * mod)
295 STACK_OF(DIST_POINT) * dps = (STACK_OF(DIST_POINT) *)
296 X509_get_ext_d2i((X509 *)cert, NID_crl_distribution_points,
299 int dpsnum = sk_DIST_POINT_num(dps);
302 uschar * list = NULL;
305 if (*mod == '>' && *++mod) sep = *mod++;
307 if (dps) for (i = 0; i < dpsnum; i++)
308 if ((dp = sk_DIST_POINT_value(dps, i)))
310 STACK_OF(GENERAL_NAME) * names = dp->distpoint->name.fullname;
312 int nnum = sk_GENERAL_NAME_num(names);
315 for (j = 0; j < nnum; j++)
316 if ( (np = sk_GENERAL_NAME_value(names, j))
317 && np->type == GEN_URI
319 list = string_append_listele(list, sep,
320 ASN1_STRING_data(np->d.uniformResourceIdentifier));
327 /*****************************************************
328 * Certificate operator routines
329 *****************************************************/
331 fingerprint(X509 * cert, const EVP_MD * fdig)
335 uschar md[EVP_MAX_MD_SIZE];
338 if (!X509_digest(cert,fdig,md,&n))
340 expand_string_message = US"tls_cert_fprt: out of mem\n";
343 cp = store_get(n*2+1);
344 for (j = 0; j < (int)n; j++) sprintf(cp+2*j, "%02X", md[j]);
349 tls_cert_fprt_md5(void * cert)
351 return fingerprint((X509 *)cert, EVP_md5());
355 tls_cert_fprt_sha1(void * cert)
357 return fingerprint((X509 *)cert, EVP_sha1());
363 /* End of tlscert-openssl.c */