1 /* $OpenBSD: tls_ocsp.c,v 1.22 2021/10/31 16:39:32 tb Exp $ */
3 * Copyright (c) 2015 Marko Kreen <markokr@gmail.com>
4 * Copyright (c) 2016 Bob Beck <beck@openbsd.org>
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 #include <sys/types.h>
21 #include <arpa/inet.h>
22 #include <netinet/in.h>
24 #include <openssl/err.h>
25 #include <openssl/ocsp.h>
26 #include <openssl/x509.h>
29 #include "tls_internal.h"
31 #define MAXAGE_SEC (14*24*60*60)
32 #define JITTER_SEC (60)
38 static struct tls_ocsp *
41 return (calloc(1, sizeof(struct tls_ocsp)));
45 tls_ocsp_free(struct tls_ocsp *ocsp)
50 X509_free(ocsp->main_cert);
51 free(ocsp->ocsp_result);
58 tls_ocsp_asn1_parse_time(struct tls *ctx, ASN1_GENERALIZEDTIME *gt, time_t *gt_time)
64 /* RFC 6960 specifies that all times in OCSP must be GENERALIZEDTIME */
65 if (ASN1_time_parse(gt->data, gt->length, &tm,
66 V_ASN1_GENERALIZEDTIME) == -1)
68 if ((*gt_time = timegm(&tm)) == -1)
74 tls_ocsp_fill_info(struct tls *ctx, int response_status, int cert_status,
75 int crl_reason, ASN1_GENERALIZEDTIME *revtime,
76 ASN1_GENERALIZEDTIME *thisupd, ASN1_GENERALIZEDTIME *nextupd)
78 struct tls_ocsp_result *info = NULL;
80 free(ctx->ocsp->ocsp_result);
81 ctx->ocsp->ocsp_result = NULL;
83 if ((info = calloc(1, sizeof (struct tls_ocsp_result))) == NULL) {
84 tls_set_error(ctx, "calloc");
87 info->response_status = response_status;
88 info->cert_status = cert_status;
89 info->crl_reason = crl_reason;
90 if (info->response_status != OCSP_RESPONSE_STATUS_SUCCESSFUL) {
92 OCSP_response_status_str(info->response_status);
93 } else if (info->cert_status != V_OCSP_CERTSTATUS_REVOKED) {
94 info->result_msg = OCSP_cert_status_str(info->cert_status);
96 info->result_msg = OCSP_crl_reason_str(info->crl_reason);
98 info->revocation_time = info->this_update = info->next_update = -1;
99 if (revtime != NULL &&
100 tls_ocsp_asn1_parse_time(ctx, revtime, &info->revocation_time) != 0) {
102 "unable to parse revocation time in OCSP reply");
105 if (thisupd != NULL &&
106 tls_ocsp_asn1_parse_time(ctx, thisupd, &info->this_update) != 0) {
108 "unable to parse this update time in OCSP reply");
111 if (nextupd != NULL &&
112 tls_ocsp_asn1_parse_time(ctx, nextupd, &info->next_update) != 0) {
114 "unable to parse next update time in OCSP reply");
117 ctx->ocsp->ocsp_result = info;
126 tls_ocsp_get_certid(X509 *main_cert, STACK_OF(X509) *extra_certs,
129 X509_NAME *issuer_name;
131 X509_STORE_CTX *storectx = NULL;
132 X509_OBJECT *obj = NULL;
133 OCSP_CERTID *cid = NULL;
136 if ((issuer_name = X509_get_issuer_name(main_cert)) == NULL)
139 if (extra_certs != NULL) {
140 issuer = X509_find_by_subject(extra_certs, issuer_name);
141 if (issuer != NULL) {
142 cid = OCSP_cert_to_id(NULL, main_cert, issuer);
147 if ((store = SSL_CTX_get_cert_store(ssl_ctx)) == NULL)
149 if ((storectx = X509_STORE_CTX_new()) == NULL)
151 if (X509_STORE_CTX_init(storectx, store, main_cert, extra_certs) != 1)
153 if ((obj = X509_STORE_CTX_get_obj_by_subject(storectx, X509_LU_X509,
154 issuer_name)) == NULL)
157 cid = OCSP_cert_to_id(NULL, main_cert, X509_OBJECT_get0_X509(obj));
160 X509_STORE_CTX_free(storectx);
161 X509_OBJECT_free(obj);
167 tls_ocsp_setup_from_peer(struct tls *ctx)
169 struct tls_ocsp *ocsp = NULL;
170 STACK_OF(OPENSSL_STRING) *ocsp_urls = NULL;
172 if ((ocsp = tls_ocsp_new()) == NULL)
175 /* steal state from ctx struct */
176 ocsp->main_cert = SSL_get_peer_certificate(ctx->ssl_conn);
177 ocsp->extra_certs = SSL_get_peer_cert_chain(ctx->ssl_conn);
178 if (ocsp->main_cert == NULL) {
179 tls_set_errorx(ctx, "no peer certificate for OCSP");
183 ocsp_urls = X509_get1_ocsp(ocsp->main_cert);
184 if (ocsp_urls == NULL) {
185 tls_set_errorx(ctx, "no OCSP URLs in peer certificate");
189 ocsp->ocsp_url = strdup(sk_OPENSSL_STRING_value(ocsp_urls, 0));
190 if (ocsp->ocsp_url == NULL) {
191 tls_set_errorx(ctx, "out of memory");
195 X509_email_free(ocsp_urls);
200 X509_email_free(ocsp_urls);
205 tls_ocsp_verify_response(struct tls *ctx, OCSP_RESPONSE *resp)
207 OCSP_BASICRESP *br = NULL;
208 ASN1_GENERALIZEDTIME *revtime = NULL, *thisupd = NULL, *nextupd = NULL;
209 OCSP_CERTID *cid = NULL;
210 STACK_OF(X509) *combined = NULL;
211 int response_status=0, cert_status=0, crl_reason=0;
215 if ((br = OCSP_response_get1_basic(resp)) == NULL) {
216 tls_set_errorx(ctx, "cannot load ocsp reply");
221 * Skip validation of 'extra_certs' as this should be done
222 * already as part of main handshake.
224 flags = OCSP_TRUSTOTHER;
227 if (OCSP_basic_verify(br, ctx->ocsp->extra_certs,
228 SSL_CTX_get_cert_store(ctx->ssl_ctx), flags) != 1) {
229 tls_set_errorx(ctx, "ocsp verify failed");
233 /* signature OK, look inside */
234 response_status = OCSP_response_status(resp);
235 if (response_status != OCSP_RESPONSE_STATUS_SUCCESSFUL) {
236 tls_set_errorx(ctx, "ocsp verify failed: response - %s",
237 OCSP_response_status_str(response_status));
241 cid = tls_ocsp_get_certid(ctx->ocsp->main_cert,
242 ctx->ocsp->extra_certs, ctx->ssl_ctx);
244 tls_set_errorx(ctx, "ocsp verify failed: no issuer cert");
248 if (OCSP_resp_find_status(br, cid, &cert_status, &crl_reason,
249 &revtime, &thisupd, &nextupd) != 1) {
250 tls_set_errorx(ctx, "ocsp verify failed: no result for cert");
254 if (OCSP_check_validity(thisupd, nextupd, JITTER_SEC,
257 "ocsp verify failed: ocsp response not current");
261 if (tls_ocsp_fill_info(ctx, response_status, cert_status,
262 crl_reason, revtime, thisupd, nextupd) != 0)
265 /* finally can look at status */
266 if (cert_status != V_OCSP_CERTSTATUS_GOOD && cert_status !=
267 V_OCSP_CERTSTATUS_UNKNOWN) {
268 tls_set_errorx(ctx, "ocsp verify failed: revoked cert - %s",
269 OCSP_crl_reason_str(crl_reason));
275 sk_X509_free(combined);
276 OCSP_CERTID_free(cid);
277 OCSP_BASICRESP_free(br);
282 * Process a raw OCSP response from an OCSP server request.
283 * OCSP details can then be retrieved with tls_peer_ocsp_* functions.
284 * returns 0 if certificate ok, -1 otherwise.
287 tls_ocsp_process_response_internal(struct tls *ctx, const unsigned char *response,
293 resp = d2i_OCSP_RESPONSE(NULL, &response, size);
295 tls_ocsp_free(ctx->ocsp);
297 tls_set_error(ctx, "unable to parse OCSP response");
300 ret = tls_ocsp_verify_response(ctx, resp);
301 OCSP_RESPONSE_free(resp);
305 /* TLS handshake verification callback for stapled requests */
307 tls_ocsp_verify_cb(SSL *ssl, void *arg)
309 const unsigned char *raw = NULL;
313 if ((ctx = SSL_get_app_data(ssl)) == NULL)
316 size = SSL_get_tlsext_status_ocsp_resp(ssl, &raw);
318 if (ctx->config->ocsp_require_stapling) {
319 tls_set_errorx(ctx, "no stapled OCSP response provided");
325 tls_ocsp_free(ctx->ocsp);
326 if ((ctx->ocsp = tls_ocsp_setup_from_peer(ctx)) == NULL)
329 if (ctx->config->verify_cert == 0 || ctx->config->verify_time == 0)
332 res = tls_ocsp_process_response_internal(ctx, raw, size);
334 return (res == 0) ? 1 : 0;
338 /* Staple the OCSP information in ctx->ocsp to the server handshake. */
340 tls_ocsp_stapling_cb(SSL *ssl, void *arg)
342 int ret = SSL_TLSEXT_ERR_ALERT_FATAL;
343 unsigned char *ocsp_staple = NULL;
346 if ((ctx = SSL_get_app_data(ssl)) == NULL)
349 if (ctx->keypair == NULL || ctx->keypair->ocsp_staple == NULL ||
350 ctx->keypair->ocsp_staple_len == 0)
351 return SSL_TLSEXT_ERR_NOACK;
353 if ((ocsp_staple = malloc(ctx->keypair->ocsp_staple_len)) == NULL)
356 memcpy(ocsp_staple, ctx->keypair->ocsp_staple,
357 ctx->keypair->ocsp_staple_len);
359 if (SSL_set_tlsext_status_ocsp_resp(ctx->ssl_conn, ocsp_staple,
360 ctx->keypair->ocsp_staple_len) != 1)
363 ret = SSL_TLSEXT_ERR_OK;
365 if (ret != SSL_TLSEXT_ERR_OK)
375 /* Retrieve OCSP URL from peer certificate, if present. */
377 tls_peer_ocsp_url(struct tls *ctx)
379 if (ctx->ocsp == NULL)
381 return ctx->ocsp->ocsp_url;
385 tls_peer_ocsp_result(struct tls *ctx)
387 if (ctx->ocsp == NULL)
389 if (ctx->ocsp->ocsp_result == NULL)
391 return ctx->ocsp->ocsp_result->result_msg;
395 tls_peer_ocsp_response_status(struct tls *ctx)
397 if (ctx->ocsp == NULL)
399 if (ctx->ocsp->ocsp_result == NULL)
401 return ctx->ocsp->ocsp_result->response_status;
405 tls_peer_ocsp_cert_status(struct tls *ctx)
407 if (ctx->ocsp == NULL)
409 if (ctx->ocsp->ocsp_result == NULL)
411 return ctx->ocsp->ocsp_result->cert_status;
415 tls_peer_ocsp_crl_reason(struct tls *ctx)
417 if (ctx->ocsp == NULL)
419 if (ctx->ocsp->ocsp_result == NULL)
421 return ctx->ocsp->ocsp_result->crl_reason;
425 tls_peer_ocsp_this_update(struct tls *ctx)
427 if (ctx->ocsp == NULL)
429 if (ctx->ocsp->ocsp_result == NULL)
431 return ctx->ocsp->ocsp_result->this_update;
435 tls_peer_ocsp_next_update(struct tls *ctx)
437 if (ctx->ocsp == NULL)
439 if (ctx->ocsp->ocsp_result == NULL)
441 return ctx->ocsp->ocsp_result->next_update;
445 tls_peer_ocsp_revocation_time(struct tls *ctx)
447 if (ctx->ocsp == NULL)
449 if (ctx->ocsp->ocsp_result == NULL)
451 return ctx->ocsp->ocsp_result->revocation_time;
455 tls_ocsp_process_response(struct tls *ctx, const unsigned char *response,
458 if ((ctx->state & TLS_HANDSHAKE_COMPLETE) == 0)
460 return tls_ocsp_process_response_internal(ctx, response, size);