1 /*
2 Copyright (c) 2009-2020 Roger Light <roger@atchoo.org>
3 Copyright (c) 2017 Bayerische Motoren Werke Aktiengesellschaft (BMW AG), Dr. Lars Voelker <lars.voelker@bmw.de>
4
5 All rights reserved. This program and the accompanying materials
6 are made available under the terms of the Eclipse Public License 2.0
7 and Eclipse Distribution License v1.0 which accompany this distribution.
8
9 The Eclipse Public License is available at
10 https://www.eclipse.org/legal/epl-2.0/
11 and the Eclipse Distribution License is available at
12 http://www.eclipse.org/org/documents/edl-v10.php.
13
14 SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
15
16 Contributors:
17 Dr. Lars Voelker, BMW AG
18 */
19
20 /*
21 COPYRIGHT AND PERMISSION NOTICE of curl on which the ocsp code is based:
22
23 Copyright (c) 1996 - 2016, Daniel Stenberg, <daniel@haxx.se>, and many
24 contributors, see the THANKS file.
25
26 All rights reserved.
27
28 Permission to use, copy, modify, and distribute this software for any purpose
29 with or without fee is hereby granted, provided that the above copyright
30 notice and this permission notice appear in all copies.
31
32 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
33 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
34 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN
35 NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
36 DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
37 OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
38 OR OTHER DEALINGS IN THE SOFTWARE.
39
40 Except as contained in this notice, the name of a copyright holder shall not
41 be used in advertising or otherwise to promote the sale, use or other dealings
42 in this Software without prior written authorization of the copyright holder.
43 */
44
45 #include "config.h"
46
47 #ifdef WITH_TLS
48 #include <logging_mosq.h>
49 #include <mosquitto_internal.h>
50 #include <net_mosq.h>
51
52 #include <openssl/safestack.h>
53 #include <openssl/tls1.h>
54 #include <openssl/ssl.h>
55 #include <openssl/ocsp.h>
56
mosquitto__verify_ocsp_status_cb(SSL * ssl,void * arg)57 int mosquitto__verify_ocsp_status_cb(SSL * ssl, void *arg)
58 {
59 struct mosquitto *mosq = (struct mosquitto *)arg;
60 int ocsp_status, result2, i;
61 unsigned char *p;
62 const unsigned char *cp;
63 OCSP_RESPONSE *rsp = NULL;
64 OCSP_BASICRESP *br = NULL;
65 X509_STORE *st = NULL;
66 STACK_OF(X509) *ch = NULL;
67 long len;
68
69 UNUSED(ssl);
70
71 len = SSL_get_tlsext_status_ocsp_resp(mosq->ssl, &p);
72 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: SSL_get_tlsext_status_ocsp_resp returned %ld bytes", len);
73
74 /* the following functions expect a const pointer */
75 cp = (const unsigned char *)p;
76
77 if (!cp || len <= 0) {
78 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: no response");
79 goto end;
80 }
81
82
83 rsp = d2i_OCSP_RESPONSE(NULL, &cp, len);
84 if (rsp==NULL) {
85 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: invalid response");
86 goto end;
87 }
88
89 ocsp_status = OCSP_response_status(rsp);
90 if(ocsp_status != OCSP_RESPONSE_STATUS_SUCCESSFUL) {
91 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: invalid status: %s (%d)",
92 OCSP_response_status_str(ocsp_status), ocsp_status);
93 goto end;
94 }
95
96 br = OCSP_response_get1_basic(rsp);
97 if (!br) {
98 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: invalid response");
99 goto end;
100 }
101
102 ch = SSL_get_peer_cert_chain(mosq->ssl);
103 if (sk_X509_num(ch) <= 0) {
104 log__printf(mosq, MOSQ_LOG_ERR, "OCSP: we did not receive certificates of the server (num: %d)", sk_X509_num(ch));
105 goto end;
106 }
107
108 st = SSL_CTX_get_cert_store(mosq->ssl_ctx);
109
110 /* Note:
111 * Other checkers often fix problems in OpenSSL before 1.0.2a (e.g. libcurl).
112 * For all currently supported versions of the OpenSSL project, this is not needed anymore.
113 */
114
115 if ((result2=OCSP_basic_verify(br, ch, st, 0)) <= 0) {
116 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: response verification failed (error: %d)", result2);
117 goto end;
118 }
119
120 for(i = 0; i < OCSP_resp_count(br); i++) {
121 int cert_status, crl_reason;
122 OCSP_SINGLERESP *single = NULL;
123
124 ASN1_GENERALIZEDTIME *rev, *thisupd, *nextupd;
125
126 single = OCSP_resp_get0(br, i);
127 if(!single)
128 continue;
129
130 cert_status = OCSP_single_get0_status(single, &crl_reason, &rev, &thisupd, &nextupd);
131
132 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: SSL certificate status: %s (%d)",
133 OCSP_cert_status_str(cert_status), cert_status);
134
135 switch(cert_status) {
136 case V_OCSP_CERTSTATUS_GOOD:
137 /* Note: A OCSP stapling result will be accepted up to 5 minutes after it expired! */
138 if(!OCSP_check_validity(thisupd, nextupd, 300L, -1L)) {
139 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: OCSP response has expired");
140 goto end;
141 }
142 break;
143
144 case V_OCSP_CERTSTATUS_REVOKED:
145 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: SSL certificate revocation reason: %s (%d)",
146 OCSP_crl_reason_str(crl_reason), crl_reason);
147 goto end;
148
149 case V_OCSP_CERTSTATUS_UNKNOWN:
150 goto end;
151
152 default:
153 log__printf(mosq, MOSQ_LOG_DEBUG, "OCSP: SSL certificate revocation status unknown");
154 goto end;
155 }
156 }
157
158 if (br!=NULL) OCSP_BASICRESP_free(br);
159 if (rsp!=NULL) OCSP_RESPONSE_free(rsp);
160 return 1; /* OK */
161
162 end:
163 if (br!=NULL) OCSP_BASICRESP_free(br);
164 if (rsp!=NULL) OCSP_RESPONSE_free(rsp);
165 return 0; /* Not OK */
166 }
167 #endif
168