1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
|
// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "net/base/x509_certificate.h"
#include <openssl/asn1.h>
#include <openssl/crypto.h>
#include <openssl/obj_mac.h>
#include <openssl/pem.h>
#include <openssl/pkcs7.h>
#include <openssl/sha.h>
#include <openssl/ssl.h>
#include <openssl/x509v3.h>
#include "base/memory/singleton.h"
#include "base/pickle.h"
#include "base/sha1.h"
#include "base/string_number_conversions.h"
#include "crypto/openssl_util.h"
#include "net/base/asn1_util.h"
#include "net/base/cert_status_flags.h"
#include "net/base/cert_verify_result.h"
#include "net/base/net_errors.h"
#include "net/base/x509_util_openssl.h"
namespace net {
namespace {
void CreateOSCertHandlesFromPKCS7Bytes(
const char* data, int length,
X509Certificate::OSCertHandles* handles) {
crypto::EnsureOpenSSLInit();
const unsigned char* der_data = reinterpret_cast<const unsigned char*>(data);
crypto::ScopedOpenSSL<PKCS7, PKCS7_free> pkcs7_cert(
d2i_PKCS7(NULL, &der_data, length));
if (!pkcs7_cert.get())
return;
STACK_OF(X509)* certs = NULL;
int nid = OBJ_obj2nid(pkcs7_cert.get()->type);
if (nid == NID_pkcs7_signed) {
certs = pkcs7_cert.get()->d.sign->cert;
} else if (nid == NID_pkcs7_signedAndEnveloped) {
certs = pkcs7_cert.get()->d.signed_and_enveloped->cert;
}
if (certs) {
for (int i = 0; i < sk_X509_num(certs); ++i) {
X509* x509_cert =
X509Certificate::DupOSCertHandle(sk_X509_value(certs, i));
handles->push_back(x509_cert);
}
}
}
void ParsePrincipalValues(X509_NAME* name,
int nid,
std::vector<std::string>* fields) {
for (int index = -1;
(index = X509_NAME_get_index_by_NID(name, nid, index)) != -1;) {
std::string field;
if (!x509_util::ParsePrincipalValueByIndex(name, index, &field))
break;
fields->push_back(field);
}
}
void ParsePrincipal(X509Certificate::OSCertHandle cert,
X509_NAME* x509_name,
CertPrincipal* principal) {
if (!x509_name)
return;
ParsePrincipalValues(x509_name, NID_streetAddress,
&principal->street_addresses);
ParsePrincipalValues(x509_name, NID_organizationName,
&principal->organization_names);
ParsePrincipalValues(x509_name, NID_organizationalUnitName,
&principal->organization_unit_names);
ParsePrincipalValues(x509_name, NID_domainComponent,
&principal->domain_components);
x509_util::ParsePrincipalValueByNID(x509_name, NID_commonName,
&principal->common_name);
x509_util::ParsePrincipalValueByNID(x509_name, NID_localityName,
&principal->locality_name);
x509_util::ParsePrincipalValueByNID(x509_name, NID_stateOrProvinceName,
&principal->state_or_province_name);
x509_util::ParsePrincipalValueByNID(x509_name, NID_countryName,
&principal->country_name);
}
void ParseSubjectAltName(X509Certificate::OSCertHandle cert,
std::vector<std::string>* dns_names,
std::vector<std::string>* ip_addresses) {
DCHECK(dns_names || ip_addresses);
int index = X509_get_ext_by_NID(cert, NID_subject_alt_name, -1);
X509_EXTENSION* alt_name_ext = X509_get_ext(cert, index);
if (!alt_name_ext)
return;
crypto::ScopedOpenSSL<GENERAL_NAMES, GENERAL_NAMES_free> alt_names(
reinterpret_cast<GENERAL_NAMES*>(X509V3_EXT_d2i(alt_name_ext)));
if (!alt_names.get())
return;
for (int i = 0; i < sk_GENERAL_NAME_num(alt_names.get()); ++i) {
const GENERAL_NAME* name = sk_GENERAL_NAME_value(alt_names.get(), i);
if (name->type == GEN_DNS && dns_names) {
const unsigned char* dns_name = ASN1_STRING_data(name->d.dNSName);
if (!dns_name)
continue;
int dns_name_len = ASN1_STRING_length(name->d.dNSName);
dns_names->push_back(
std::string(reinterpret_cast<const char*>(dns_name), dns_name_len));
} else if (name->type == GEN_IPADD && ip_addresses) {
const unsigned char* ip_addr = name->d.iPAddress->data;
if (!ip_addr)
continue;
int ip_addr_len = name->d.iPAddress->length;
if (ip_addr_len != 4 && ip_addr_len != 8) {
// http://www.ietf.org/rfc/rfc3280.txt requires subjectAltName iPAddress
// to have 4 or 16 bytes, whereas in a name constraint it includes a
// net mask hence 8 or 32 bytes. Logging to help diagnose any mixup.
LOG(WARNING) << "Bad sized IP Address in cert: " << ip_addr_len;
continue;
}
ip_addresses->push_back(
std::string(reinterpret_cast<const char*>(ip_addr), ip_addr_len));
}
}
}
// Maps X509_STORE_CTX_get_error() return values to our cert status flags.
int MapCertErrorToCertStatus(int err) {
switch (err) {
case X509_V_ERR_SUBJECT_ISSUER_MISMATCH:
return CERT_STATUS_COMMON_NAME_INVALID;
case X509_V_ERR_CERT_NOT_YET_VALID:
case X509_V_ERR_CERT_HAS_EXPIRED:
case X509_V_ERR_CRL_NOT_YET_VALID:
case X509_V_ERR_CRL_HAS_EXPIRED:
case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
case X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD:
case X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD:
return CERT_STATUS_DATE_INVALID;
case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
case X509_V_ERR_UNABLE_TO_GET_CRL:
case X509_V_ERR_INVALID_CA:
case X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER:
case X509_V_ERR_INVALID_NON_CA:
case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
case X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN:
case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY:
return CERT_STATUS_AUTHORITY_INVALID;
#if 0
// TODO(bulach): what should we map to these status?
return CERT_STATUS_NO_REVOCATION_MECHANISM;
return CERT_STATUS_UNABLE_TO_CHECK_REVOCATION;
return CERT_STATUS_NOT_IN_DNS;
#endif
case X509_V_ERR_CERT_REVOKED:
return CERT_STATUS_REVOKED;
case X509_V_ERR_KEYUSAGE_NO_CERTSIGN:
return CERT_STATUS_WEAK_SIGNATURE_ALGORITHM;
// All these status are mapped to CERT_STATUS_INVALID.
case X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE:
case X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE:
case X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY:
case X509_V_ERR_CERT_SIGNATURE_FAILURE:
case X509_V_ERR_CRL_SIGNATURE_FAILURE:
case X509_V_ERR_OUT_OF_MEM:
case X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE:
case X509_V_ERR_CERT_CHAIN_TOO_LONG:
case X509_V_ERR_PATH_LENGTH_EXCEEDED:
case X509_V_ERR_INVALID_PURPOSE:
case X509_V_ERR_CERT_UNTRUSTED:
case X509_V_ERR_CERT_REJECTED:
case X509_V_ERR_AKID_SKID_MISMATCH:
case X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH:
case X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION:
case X509_V_ERR_KEYUSAGE_NO_CRL_SIGN:
case X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION:
case X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED:
case X509_V_ERR_KEYUSAGE_NO_DIGITAL_SIGNATURE:
case X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED:
case X509_V_ERR_INVALID_EXTENSION:
case X509_V_ERR_INVALID_POLICY_EXTENSION:
case X509_V_ERR_NO_EXPLICIT_POLICY:
case X509_V_ERR_UNNESTED_RESOURCE:
case X509_V_ERR_APPLICATION_VERIFICATION:
return CERT_STATUS_INVALID;
default:
NOTREACHED() << "Invalid X509 err " << err;
return CERT_STATUS_INVALID;
}
}
// sk_X509_free is a function-style macro, so can't be used as a template
// param directly.
void sk_X509_free_fn(STACK_OF(X509)* st) {
sk_X509_free(st);
}
struct DERCache {
unsigned char* data;
int data_length;
};
void DERCache_free(void* parent, void* ptr, CRYPTO_EX_DATA* ad, int idx,
long argl, void* argp) {
DERCache* der_cache = static_cast<DERCache*>(ptr);
if (!der_cache)
return;
if (der_cache->data)
OPENSSL_free(der_cache->data);
OPENSSL_free(der_cache);
}
class X509InitSingleton {
public:
static X509InitSingleton* GetInstance() {
// We allow the X509 store to leak, because it is used from a non-joinable
// worker that is not stopped on shutdown, hence may still be using
// OpenSSL library after the AtExit runner has completed.
return Singleton<X509InitSingleton,
LeakySingletonTraits<X509InitSingleton> >::get();
}
int der_cache_ex_index() const { return der_cache_ex_index_; }
X509_STORE* store() const { return store_.get(); }
void ResetCertStore() {
store_.reset(X509_STORE_new());
DCHECK(store_.get());
X509_STORE_set_default_paths(store_.get());
// TODO(joth): Enable CRL (see X509_STORE_set_flags(X509_V_FLAG_CRL_CHECK)).
}
private:
friend struct DefaultSingletonTraits<X509InitSingleton>;
X509InitSingleton() {
crypto::EnsureOpenSSLInit();
der_cache_ex_index_ = X509_get_ex_new_index(0, 0, 0, 0, DERCache_free);
DCHECK_NE(der_cache_ex_index_, -1);
ResetCertStore();
}
int der_cache_ex_index_;
crypto::ScopedOpenSSL<X509_STORE, X509_STORE_free> store_;
DISALLOW_COPY_AND_ASSIGN(X509InitSingleton);
};
// Takes ownership of |data| (which must have been allocated by OpenSSL).
DERCache* SetDERCache(X509Certificate::OSCertHandle cert,
int x509_der_cache_index,
unsigned char* data,
int data_length) {
DERCache* internal_cache = static_cast<DERCache*>(
OPENSSL_malloc(sizeof(*internal_cache)));
if (!internal_cache) {
// We took ownership of |data|, so we must free if we can't add it to
// |cert|.
OPENSSL_free(data);
return NULL;
}
internal_cache->data = data;
internal_cache->data_length = data_length;
X509_set_ex_data(cert, x509_der_cache_index, internal_cache);
return internal_cache;
}
// Returns true if |der_cache| points to valid data, false otherwise.
// (note: the DER-encoded data in |der_cache| is owned by |cert|, callers should
// not free it).
bool GetDERAndCacheIfNeeded(X509Certificate::OSCertHandle cert,
DERCache* der_cache) {
int x509_der_cache_index =
X509InitSingleton::GetInstance()->der_cache_ex_index();
// Re-encoding the DER data via i2d_X509 is an expensive operation, but it's
// necessary for comparing two certificates. We re-encode at most once per
// certificate and cache the data within the X509 cert using X509_set_ex_data.
DERCache* internal_cache = static_cast<DERCache*>(
X509_get_ex_data(cert, x509_der_cache_index));
if (!internal_cache) {
unsigned char* data = NULL;
int data_length = i2d_X509(cert, &data);
if (data_length <= 0 || !data)
return false;
internal_cache = SetDERCache(cert, x509_der_cache_index, data, data_length);
if (!internal_cache)
return false;
}
*der_cache = *internal_cache;
return true;
}
} // namespace
// static
X509Certificate::OSCertHandle X509Certificate::DupOSCertHandle(
OSCertHandle cert_handle) {
DCHECK(cert_handle);
// Using X509_dup causes the entire certificate to be reparsed. This
// conversion, besides being non-trivial, drops any associated
// application-specific data set by X509_set_ex_data. Using CRYPTO_add
// just bumps up the ref-count for the cert, without causing any allocations
// or deallocations.
CRYPTO_add(&cert_handle->references, 1, CRYPTO_LOCK_X509);
return cert_handle;
}
// static
void X509Certificate::FreeOSCertHandle(OSCertHandle cert_handle) {
// Decrement the ref-count for the cert and, if all references are gone,
// free the memory and any application-specific data associated with the
// certificate.
X509_free(cert_handle);
}
void X509Certificate::Initialize() {
crypto::EnsureOpenSSLInit();
fingerprint_ = CalculateFingerprint(cert_handle_);
ASN1_INTEGER* num = X509_get_serialNumber(cert_handle_);
if (num) {
serial_number_ = std::string(
reinterpret_cast<char*>(num->data),
num->length);
// Remove leading zeros.
while (serial_number_.size() > 1 && serial_number_[0] == 0)
serial_number_ = serial_number_.substr(1, serial_number_.size() - 1);
}
ParsePrincipal(cert_handle_, X509_get_subject_name(cert_handle_), &subject_);
ParsePrincipal(cert_handle_, X509_get_issuer_name(cert_handle_), &issuer_);
x509_util::ParseDate(X509_get_notBefore(cert_handle_), &valid_start_);
x509_util::ParseDate(X509_get_notAfter(cert_handle_), &valid_expiry_);
}
// static
void X509Certificate::ResetCertStore() {
X509InitSingleton::GetInstance()->ResetCertStore();
}
SHA1Fingerprint X509Certificate::CalculateFingerprint(OSCertHandle cert) {
SHA1Fingerprint sha1;
unsigned int sha1_size = static_cast<unsigned int>(sizeof(sha1.data));
int ret = X509_digest(cert, EVP_sha1(), sha1.data, &sha1_size);
CHECK(ret);
CHECK_EQ(sha1_size, sizeof(sha1.data));
return sha1;
}
// static
X509Certificate::OSCertHandle X509Certificate::CreateOSCertHandleFromBytes(
const char* data, int length) {
if (length < 0)
return NULL;
crypto::EnsureOpenSSLInit();
const unsigned char* d2i_data =
reinterpret_cast<const unsigned char*>(data);
// Don't cache this data via SetDERCache as this wire format may be not be
// identical from the i2d_X509 roundtrip.
X509* cert = d2i_X509(NULL, &d2i_data, length);
return cert;
}
// static
X509Certificate::OSCertHandles X509Certificate::CreateOSCertHandlesFromBytes(
const char* data, int length, Format format) {
OSCertHandles results;
if (length < 0)
return results;
switch (format) {
case FORMAT_SINGLE_CERTIFICATE: {
OSCertHandle handle = CreateOSCertHandleFromBytes(data, length);
if (handle)
results.push_back(handle);
break;
}
case FORMAT_PKCS7: {
CreateOSCertHandlesFromPKCS7Bytes(data, length, &results);
break;
}
default: {
NOTREACHED() << "Certificate format " << format << " unimplemented";
break;
}
}
return results;
}
// static
X509Certificate* X509Certificate::CreateSelfSigned(
crypto::RSAPrivateKey* key,
const std::string& subject,
uint32 serial_number,
base::TimeDelta valid_duration) {
// TODO(port): Implement. See http://crbug.com/91512.
NOTIMPLEMENTED();
return NULL;
}
void X509Certificate::GetSubjectAltName(
std::vector<std::string>* dns_names,
std::vector<std::string>* ip_addrs) const {
if (dns_names)
dns_names->clear();
if (ip_addrs)
ip_addrs->clear();
ParseSubjectAltName(cert_handle_, dns_names, ip_addrs);
}
// static
X509_STORE* X509Certificate::cert_store() {
return X509InitSingleton::GetInstance()->store();
}
int X509Certificate::VerifyInternal(const std::string& hostname,
int flags,
CertVerifyResult* verify_result) const {
if (!VerifyNameMatch(hostname))
verify_result->cert_status |= CERT_STATUS_COMMON_NAME_INVALID;
crypto::ScopedOpenSSL<X509_STORE_CTX, X509_STORE_CTX_free> ctx(
X509_STORE_CTX_new());
crypto::ScopedOpenSSL<STACK_OF(X509), sk_X509_free_fn> intermediates(
sk_X509_new_null());
if (!intermediates.get())
return ERR_OUT_OF_MEMORY;
for (OSCertHandles::const_iterator it = intermediate_ca_certs_.begin();
it != intermediate_ca_certs_.end(); ++it) {
if (!sk_X509_push(intermediates.get(), *it))
return ERR_OUT_OF_MEMORY;
}
int rv = X509_STORE_CTX_init(ctx.get(), cert_store(),
cert_handle_, intermediates.get());
CHECK_EQ(1, rv);
if (X509_verify_cert(ctx.get()) != 1) {
int x509_error = X509_STORE_CTX_get_error(ctx.get());
int cert_status = MapCertErrorToCertStatus(x509_error);
LOG(ERROR) << "X509 Verification error "
<< X509_verify_cert_error_string(x509_error)
<< " : " << x509_error
<< " : " << X509_STORE_CTX_get_error_depth(ctx.get())
<< " : " << cert_status;
verify_result->cert_status |= cert_status;
}
if (IsCertStatusError(verify_result->cert_status))
return MapCertStatusToNetError(verify_result->cert_status);
STACK_OF(X509)* chain = X509_STORE_CTX_get_chain(ctx.get());
X509* verified_cert = NULL;
std::vector<X509*> verified_chain;
for (int i = 0; i < sk_X509_num(chain); ++i) {
X509* cert = sk_X509_value(chain, i);
if (i == 0) {
verified_cert = cert;
} else {
verified_chain.push_back(cert);
}
DERCache der_cache;
if (!GetDERAndCacheIfNeeded(cert, &der_cache))
continue;
base::StringPiece der_bytes(reinterpret_cast<const char*>(der_cache.data),
der_cache.data_length);
base::StringPiece spki_bytes;
if (!asn1::ExtractSPKIFromDERCert(der_bytes, &spki_bytes))
continue;
SHA1Fingerprint hash;
base::SHA1HashBytes(reinterpret_cast<const uint8*>(spki_bytes.data()),
spki_bytes.size(), hash.data);
verify_result->public_key_hashes.push_back(hash);
}
if (verified_cert) {
verify_result->verified_cert = CreateFromHandle(verified_cert,
verified_chain);
}
// Currently we only ues OpenSSL's default root CA paths, so treat all
// correctly verified certs as being from a known root. TODO(joth): if the
// motivations described in http://src.chromium.org/viewvc/chrome?view=rev&revision=80778
// become an issue on OpenSSL builds, we will need to embed a hardcoded list
// of well known root CAs, as per the _mac and _win versions.
verify_result->is_issued_by_known_root = true;
return OK;
}
bool X509Certificate::GetDEREncoded(std::string* encoded) {
DERCache der_cache;
if (!GetDERAndCacheIfNeeded(cert_handle_, &der_cache))
return false;
encoded->assign(reinterpret_cast<const char*>(der_cache.data),
der_cache.data_length);
return true;
}
// static
bool X509Certificate::IsSameOSCert(X509Certificate::OSCertHandle a,
X509Certificate::OSCertHandle b) {
DCHECK(a && b);
if (a == b)
return true;
// X509_cmp only checks the fingerprint, but we want to compare the whole
// DER data. Encoding it from OSCertHandle is an expensive operation, so we
// cache the DER (if not already cached via X509_set_ex_data).
DERCache der_cache_a, der_cache_b;
return GetDERAndCacheIfNeeded(a, &der_cache_a) &&
GetDERAndCacheIfNeeded(b, &der_cache_b) &&
der_cache_a.data_length == der_cache_b.data_length &&
memcmp(der_cache_a.data, der_cache_b.data, der_cache_a.data_length) == 0;
}
// static
X509Certificate::OSCertHandle
X509Certificate::ReadOSCertHandleFromPickle(const Pickle& pickle,
void** pickle_iter) {
const char* data;
int length;
if (!pickle.ReadData(pickle_iter, &data, &length))
return NULL;
return CreateOSCertHandleFromBytes(data, length);
}
// static
bool X509Certificate::WriteOSCertHandleToPickle(OSCertHandle cert_handle,
Pickle* pickle) {
DERCache der_cache;
if (!GetDERAndCacheIfNeeded(cert_handle, &der_cache))
return false;
return pickle->WriteData(
reinterpret_cast<const char*>(der_cache.data),
der_cache.data_length);
}
} // namespace net
|