1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "net/cert/x509_util_mac.h"
6
7 #include "base/logging.h"
8 #include "third_party/apple_apsl/cssmapplePriv.h"
9
10 namespace net {
11
12 namespace x509_util {
13
14 namespace {
15
16 // Creates a SecPolicyRef for the given OID, with optional value.
CreatePolicy(const CSSM_OID * policy_oid,void * option_data,size_t option_length,SecPolicyRef * policy)17 OSStatus CreatePolicy(const CSSM_OID* policy_oid,
18 void* option_data,
19 size_t option_length,
20 SecPolicyRef* policy) {
21 SecPolicySearchRef search;
22 OSStatus err = SecPolicySearchCreate(CSSM_CERT_X_509v3, policy_oid, NULL,
23 &search);
24 if (err)
25 return err;
26 err = SecPolicySearchCopyNext(search, policy);
27 CFRelease(search);
28 if (err)
29 return err;
30
31 if (option_data) {
32 CSSM_DATA options_data = {
33 option_length,
34 reinterpret_cast<uint8_t*>(option_data)
35 };
36 err = SecPolicySetValue(*policy, &options_data);
37 if (err) {
38 CFRelease(*policy);
39 return err;
40 }
41 }
42 return noErr;
43 }
44
45 } // namespace
46
47
CreateSSLClientPolicy(SecPolicyRef * policy)48 OSStatus CreateSSLClientPolicy(SecPolicyRef* policy) {
49 CSSM_APPLE_TP_SSL_OPTIONS tp_ssl_options;
50 memset(&tp_ssl_options, 0, sizeof(tp_ssl_options));
51 tp_ssl_options.Version = CSSM_APPLE_TP_SSL_OPTS_VERSION;
52 tp_ssl_options.Flags |= CSSM_APPLE_TP_SSL_CLIENT;
53
54 return CreatePolicy(&CSSMOID_APPLE_TP_SSL, &tp_ssl_options,
55 sizeof(tp_ssl_options), policy);
56 }
57
CreateSSLServerPolicy(const std::string & hostname,SecPolicyRef * policy)58 OSStatus CreateSSLServerPolicy(const std::string& hostname,
59 SecPolicyRef* policy) {
60 CSSM_APPLE_TP_SSL_OPTIONS tp_ssl_options;
61 memset(&tp_ssl_options, 0, sizeof(tp_ssl_options));
62 tp_ssl_options.Version = CSSM_APPLE_TP_SSL_OPTS_VERSION;
63 if (!hostname.empty()) {
64 tp_ssl_options.ServerName = hostname.data();
65 tp_ssl_options.ServerNameLen = hostname.size();
66 }
67
68 return CreatePolicy(&CSSMOID_APPLE_TP_SSL, &tp_ssl_options,
69 sizeof(tp_ssl_options), policy);
70 }
71
CreateBasicX509Policy(SecPolicyRef * policy)72 OSStatus CreateBasicX509Policy(SecPolicyRef* policy) {
73 return CreatePolicy(&CSSMOID_APPLE_X509_BASIC, NULL, 0, policy);
74 }
75
CreateRevocationPolicies(bool enable_revocation_checking,bool enable_ev_checking,CFMutableArrayRef policies)76 OSStatus CreateRevocationPolicies(bool enable_revocation_checking,
77 bool enable_ev_checking,
78 CFMutableArrayRef policies) {
79 OSStatus status = noErr;
80
81 // In order to bypass the system revocation checking settings, the
82 // SecTrustRef must have at least one revocation policy associated with it.
83 // Since it is not known prior to verification whether the Apple TP will
84 // consider a certificate as an EV candidate, the default policy used is a
85 // CRL policy, since it does not communicate over the network.
86 // If the TP believes the leaf is an EV cert, it will explicitly add an
87 // OCSP policy to perform the online checking, and if it doesn't believe
88 // that the leaf is EV, then the default CRL policy will effectively no-op.
89 // This behaviour is used to implement EV-only revocation checking.
90 if (enable_ev_checking || enable_revocation_checking) {
91 CSSM_APPLE_TP_CRL_OPTIONS tp_crl_options;
92 memset(&tp_crl_options, 0, sizeof(tp_crl_options));
93 tp_crl_options.Version = CSSM_APPLE_TP_CRL_OPTS_VERSION;
94 // Only allow network CRL fetches if the caller explicitly requests
95 // online revocation checking. Note that, as of OS X 10.7.2, the system
96 // will set force this flag on according to system policies, so
97 // online revocation checks cannot be completely disabled.
98 if (enable_revocation_checking)
99 tp_crl_options.CrlFlags = CSSM_TP_ACTION_FETCH_CRL_FROM_NET;
100
101 SecPolicyRef crl_policy;
102 status = CreatePolicy(&CSSMOID_APPLE_TP_REVOCATION_CRL, &tp_crl_options,
103 sizeof(tp_crl_options), &crl_policy);
104 if (status)
105 return status;
106 CFArrayAppendValue(policies, crl_policy);
107 CFRelease(crl_policy);
108 }
109
110 // If revocation checking is explicitly enabled, then add an OCSP policy
111 // and allow network access. If both revocation checking and EV checking
112 // are disabled, then the added OCSP policy will be prevented from
113 // accessing the network. This is done because the TP will force an OCSP
114 // policy to be present when it believes the certificate is EV. If network
115 // fetching was not explicitly disabled, then it would be as if
116 // enable_ev_checking was always set to true.
117 if (enable_revocation_checking || !enable_ev_checking) {
118 CSSM_APPLE_TP_OCSP_OPTIONS tp_ocsp_options;
119 memset(&tp_ocsp_options, 0, sizeof(tp_ocsp_options));
120 tp_ocsp_options.Version = CSSM_APPLE_TP_OCSP_OPTS_VERSION;
121
122 if (enable_revocation_checking) {
123 // The default for the OCSP policy is to fetch responses via the network,
124 // unlike the CRL policy default. The policy is further modified to
125 // prefer OCSP over CRLs, if both are specified on the certificate. This
126 // is because an OCSP response is both sufficient and typically
127 // significantly smaller than the CRL counterpart.
128 tp_ocsp_options.Flags = CSSM_TP_ACTION_OCSP_SUFFICIENT;
129 } else {
130 // Effectively disable OCSP checking by making it impossible to get an
131 // OCSP response. Even if the Apple TP forces OCSP, no checking will
132 // be able to succeed. If this happens, the Apple TP will report an error
133 // that OCSP was unavailable, but this will be handled and suppressed in
134 // X509Certificate::Verify().
135 tp_ocsp_options.Flags = CSSM_TP_ACTION_OCSP_DISABLE_NET |
136 CSSM_TP_ACTION_OCSP_CACHE_READ_DISABLE;
137 }
138
139 SecPolicyRef ocsp_policy;
140 status = CreatePolicy(&CSSMOID_APPLE_TP_REVOCATION_OCSP, &tp_ocsp_options,
141 sizeof(tp_ocsp_options), &ocsp_policy);
142 if (status)
143 return status;
144 CFArrayAppendValue(policies, ocsp_policy);
145 CFRelease(ocsp_policy);
146 }
147
148 return status;
149 }
150
CSSMFieldValue()151 CSSMFieldValue::CSSMFieldValue()
152 : cl_handle_(CSSM_INVALID_HANDLE),
153 oid_(NULL),
154 field_(NULL) {
155 }
CSSMFieldValue(CSSM_CL_HANDLE cl_handle,const CSSM_OID * oid,CSSM_DATA_PTR field)156 CSSMFieldValue::CSSMFieldValue(CSSM_CL_HANDLE cl_handle,
157 const CSSM_OID* oid,
158 CSSM_DATA_PTR field)
159 : cl_handle_(cl_handle),
160 oid_(const_cast<CSSM_OID_PTR>(oid)),
161 field_(field) {
162 }
163
~CSSMFieldValue()164 CSSMFieldValue::~CSSMFieldValue() {
165 Reset(CSSM_INVALID_HANDLE, NULL, NULL);
166 }
167
Reset(CSSM_CL_HANDLE cl_handle,CSSM_OID_PTR oid,CSSM_DATA_PTR field)168 void CSSMFieldValue::Reset(CSSM_CL_HANDLE cl_handle,
169 CSSM_OID_PTR oid,
170 CSSM_DATA_PTR field) {
171 if (cl_handle_ && oid_ && field_)
172 CSSM_CL_FreeFieldValue(cl_handle_, oid_, field_);
173 cl_handle_ = cl_handle;
174 oid_ = oid;
175 field_ = field;
176 }
177
CSSMCachedCertificate()178 CSSMCachedCertificate::CSSMCachedCertificate()
179 : cl_handle_(CSSM_INVALID_HANDLE),
180 cached_cert_handle_(CSSM_INVALID_HANDLE) {
181 }
~CSSMCachedCertificate()182 CSSMCachedCertificate::~CSSMCachedCertificate() {
183 if (cl_handle_ && cached_cert_handle_)
184 CSSM_CL_CertAbortCache(cl_handle_, cached_cert_handle_);
185 }
186
Init(SecCertificateRef os_cert_handle)187 OSStatus CSSMCachedCertificate::Init(SecCertificateRef os_cert_handle) {
188 DCHECK(!cl_handle_ && !cached_cert_handle_);
189 DCHECK(os_cert_handle);
190 CSSM_DATA cert_data;
191 OSStatus status = SecCertificateGetData(os_cert_handle, &cert_data);
192 if (status)
193 return status;
194 status = SecCertificateGetCLHandle(os_cert_handle, &cl_handle_);
195 if (status) {
196 DCHECK(!cl_handle_);
197 return status;
198 }
199
200 status = CSSM_CL_CertCache(cl_handle_, &cert_data, &cached_cert_handle_);
201 if (status)
202 DCHECK(!cached_cert_handle_);
203 return status;
204 }
205
GetField(const CSSM_OID * field_oid,CSSMFieldValue * field) const206 OSStatus CSSMCachedCertificate::GetField(const CSSM_OID* field_oid,
207 CSSMFieldValue* field) const {
208 DCHECK(cl_handle_);
209 DCHECK(cached_cert_handle_);
210
211 CSSM_OID_PTR oid = const_cast<CSSM_OID_PTR>(field_oid);
212 CSSM_DATA_PTR field_ptr = NULL;
213 CSSM_HANDLE results_handle = CSSM_INVALID_HANDLE;
214 uint32 field_value_count = 0;
215 CSSM_RETURN status = CSSM_CL_CertGetFirstCachedFieldValue(
216 cl_handle_, cached_cert_handle_, oid, &results_handle,
217 &field_value_count, &field_ptr);
218 if (status)
219 return status;
220
221 // Note: |field_value_count| may be > 1, indicating that more than one
222 // value is present. This may happen with extensions, but for current
223 // usages, only the first value is returned.
224 CSSM_CL_CertAbortQuery(cl_handle_, results_handle);
225 field->Reset(cl_handle_, oid, field_ptr);
226 return CSSM_OK;
227 }
228
229 } // namespace x509_util
230
231 } // namespace net
232