// Copyright (c) 2006-2008 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 "base/logging.h"
#include "base/pickle.h"
#include "base/string_tokenizer.h"
#include "base/string_util.h"
#include "net/base/cert_status_flags.h"
#include "net/base/cert_verify_result.h"
#include "net/base/ev_root_ca_metadata.h"
#include "net/base/net_errors.h"
#include "net/base/scoped_cert_chain_context.h"
#pragma comment(lib, "crypt32.lib")
using base::Time;
namespace net {
namespace {
//-----------------------------------------------------------------------------
// TODO(wtc): This is a copy of the MapSecurityError function in
// ssl_client_socket_win.cc. Another function that maps Windows error codes
// to our network error codes is WinInetUtil::OSErrorToNetError. We should
// eliminate the code duplication.
int MapSecurityError(SECURITY_STATUS err) {
// There are numerous security error codes, but these are the ones we thus
// far find interesting.
switch (err) {
case SEC_E_WRONG_PRINCIPAL: // Schannel
case CERT_E_CN_NO_MATCH: // CryptoAPI
return ERR_CERT_COMMON_NAME_INVALID;
case SEC_E_UNTRUSTED_ROOT: // Schannel
case CERT_E_UNTRUSTEDROOT: // CryptoAPI
return ERR_CERT_AUTHORITY_INVALID;
case SEC_E_CERT_EXPIRED: // Schannel
case CERT_E_EXPIRED: // CryptoAPI
return ERR_CERT_DATE_INVALID;
case CRYPT_E_NO_REVOCATION_CHECK:
return ERR_CERT_NO_REVOCATION_MECHANISM;
case CRYPT_E_REVOCATION_OFFLINE:
return ERR_CERT_UNABLE_TO_CHECK_REVOCATION;
case CRYPT_E_REVOKED: // Schannel and CryptoAPI
return ERR_CERT_REVOKED;
case SEC_E_CERT_UNKNOWN:
case CERT_E_ROLE:
return ERR_CERT_INVALID;
// We received an unexpected_message or illegal_parameter alert message
// from the server.
case SEC_E_ILLEGAL_MESSAGE:
return ERR_SSL_PROTOCOL_ERROR;
case SEC_E_ALGORITHM_MISMATCH:
return ERR_SSL_VERSION_OR_CIPHER_MISMATCH;
case SEC_E_INVALID_HANDLE:
return ERR_UNEXPECTED;
case SEC_E_OK:
return OK;
default:
LOG(WARNING) << "Unknown error " << err << " mapped to net::ERR_FAILED";
return ERR_FAILED;
}
}
// Map the errors in the chain_context->TrustStatus.dwErrorStatus returned by
// CertGetCertificateChain to our certificate status flags.
int MapCertChainErrorStatusToCertStatus(DWORD error_status) {
int cert_status = 0;
// CERT_TRUST_IS_NOT_TIME_NESTED means a subject certificate's time validity
// does not nest correctly within its issuer's time validity.
const DWORD kDateInvalidErrors = CERT_TRUST_IS_NOT_TIME_VALID |
CERT_TRUST_IS_NOT_TIME_NESTED |
CERT_TRUST_CTL_IS_NOT_TIME_VALID;
if (error_status & kDateInvalidErrors)
cert_status |= CERT_STATUS_DATE_INVALID;
const DWORD kAuthorityInvalidErrors = CERT_TRUST_IS_UNTRUSTED_ROOT |
CERT_TRUST_IS_EXPLICIT_DISTRUST |
CERT_TRUST_IS_PARTIAL_CHAIN;
if (error_status & kAuthorityInvalidErrors)
cert_status |= CERT_STATUS_AUTHORITY_INVALID;
if ((error_status & CERT_TRUST_REVOCATION_STATUS_UNKNOWN) &&
!(error_status & CERT_TRUST_IS_OFFLINE_REVOCATION))
cert_status |= CERT_STATUS_NO_REVOCATION_MECHANISM;
if (error_status & CERT_TRUST_IS_OFFLINE_REVOCATION)
cert_status |= CERT_STATUS_UNABLE_TO_CHECK_REVOCATION;
if (error_status & CERT_TRUST_IS_REVOKED)
cert_status |= CERT_STATUS_REVOKED;
const DWORD kWrongUsageErrors = CERT_TRUST_IS_NOT_VALID_FOR_USAGE |
CERT_TRUST_CTL_IS_NOT_VALID_FOR_USAGE;
if (error_status & kWrongUsageErrors) {
// TODO(wtc): Handle these errors.
// cert_status = |= CERT_STATUS_WRONG_USAGE;
}
// The rest of the errors.
const DWORD kCertInvalidErrors =
CERT_TRUST_IS_NOT_SIGNATURE_VALID |
CERT_TRUST_IS_CYCLIC |
CERT_TRUST_INVALID_EXTENSION |
CERT_TRUST_INVALID_POLICY_CONSTRAINTS |
CERT_TRUST_INVALID_BASIC_CONSTRAINTS |
CERT_TRUST_INVALID_NAME_CONSTRAINTS |
CERT_TRUST_CTL_IS_NOT_SIGNATURE_VALID |
CERT_TRUST_HAS_NOT_SUPPORTED_NAME_CONSTRAINT |
CERT_TRUST_HAS_NOT_DEFINED_NAME_CONSTRAINT |
CERT_TRUST_HAS_NOT_PERMITTED_NAME_CONSTRAINT |
CERT_TRUST_HAS_EXCLUDED_NAME_CONSTRAINT |
CERT_TRUST_NO_ISSUANCE_CHAIN_POLICY |
CERT_TRUST_HAS_NOT_SUPPORTED_CRITICAL_EXT;
if (error_status & kCertInvalidErrors)
cert_status |= CERT_STATUS_INVALID;
return cert_status;
}
//-----------------------------------------------------------------------------
// Wrappers of malloc and free for CRYPT_DECODE_PARA, which requires the
// WINAPI calling convention.
void* WINAPI MyCryptAlloc(size_t size) {
return malloc(size);
}
void WINAPI MyCryptFree(void* p) {
free(p);
}
// Decodes the cert's subjectAltName extension into a CERT_ALT_NAME_INFO
// structure and stores it in *output.
void GetCertSubjectAltName(PCCERT_CONTEXT cert,
scoped_ptr_malloc<CERT_ALT_NAME_INFO>* output) {
PCERT_EXTENSION extension = CertFindExtension(szOID_SUBJECT_ALT_NAME2,
cert->pCertInfo->cExtension,
cert->pCertInfo->rgExtension);
if (!extension)
return;
CRYPT_DECODE_PARA decode_para;
decode_para.cbSize = sizeof(decode_para);
decode_para.pfnAlloc = MyCryptAlloc;
decode_para.pfnFree = MyCryptFree;
CERT_ALT_NAME_INFO* alt_name_info = NULL;
DWORD alt_name_info_size = 0;
BOOL rv;
rv = CryptDecodeObjectEx(X509_ASN_ENCODING | PKCS_7_ASN_ENCODING,
szOID_SUBJECT_ALT_NAME2,
extension->Value.pbData,
extension->Value.cbData,
CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG,
&decode_para,
&alt_name_info,
&alt_name_info_size);
if (rv)
output->reset(alt_name_info);
}
// Returns true if any common name in the certificate's Subject field contains
// a NULL character.
bool CertSubjectCommonNameHasNull(PCCERT_CONTEXT cert) {
CRYPT_DECODE_PARA decode_para;
decode_para.cbSize = sizeof(decode_para);
decode_para.pfnAlloc = MyCryptAlloc;
decode_para.pfnFree = MyCryptFree;
CERT_NAME_INFO* name_info = NULL;
DWORD name_info_size = 0;
BOOL rv;
rv = CryptDecodeObjectEx(X509_ASN_ENCODING | PKCS_7_ASN_ENCODING,
X509_NAME,
cert->pCertInfo->Subject.pbData,
cert->pCertInfo->Subject.cbData,
CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG,
&decode_para,
&name_info,
&name_info_size);
if (rv) {
scoped_ptr_malloc<CERT_NAME_INFO> scoped_name_info(name_info);
// The Subject field may have multiple common names. According to the
// "PKI Layer Cake" paper, CryptoAPI uses every common name in the
// Subject field, so we inspect every common name.
//
// From RFC 5280:
// X520CommonName ::= CHOICE {
// teletexString TeletexString (SIZE (1..ub-common-name)),
// printableString PrintableString (SIZE (1..ub-common-name)),
// universalString UniversalString (SIZE (1..ub-common-name)),
// utf8String UTF8String (SIZE (1..ub-common-name)),
// bmpString BMPString (SIZE (1..ub-common-name)) }
//
// We also check IA5String and VisibleString.
for (DWORD i = 0; i < name_info->cRDN; ++i) {
PCERT_RDN rdn = &name_info->rgRDN[i];
for (DWORD j = 0; j < rdn->cRDNAttr; ++j) {
PCERT_RDN_ATTR rdn_attr = &rdn->rgRDNAttr[j];
if (strcmp(rdn_attr->pszObjId, szOID_COMMON_NAME) == 0) {
switch (rdn_attr->dwValueType) {
// After the CryptoAPI ASN.1 security vulnerabilities described in
// http://www.microsoft.com/technet/security/Bulletin/MS09-056.mspx
// were patched, we get CERT_RDN_ENCODED_BLOB for a common name
// that contains a NULL character.
case CERT_RDN_ENCODED_BLOB:
break;
// Array of 8-bit characters.
case CERT_RDN_PRINTABLE_STRING:
case CERT_RDN_TELETEX_STRING:
case CERT_RDN_IA5_STRING:
case CERT_RDN_VISIBLE_STRING:
for (DWORD k = 0; k < rdn_attr->Value.cbData; ++k) {
if (rdn_attr->Value.pbData[k] == '\0')
return true;
}
break;
// Array of 16-bit characters.
case CERT_RDN_BMP_STRING:
case CERT_RDN_UTF8_STRING: {
DWORD num_wchars = rdn_attr->Value.cbData / 2;
wchar_t* common_name =
reinterpret_cast<wchar_t*>(rdn_attr->Value.pbData);
for (DWORD k = 0; k < num_wchars; ++k) {
if (common_name[k] == L'\0')
return true;
}
break;
}
// Array of ints (32-bit).
case CERT_RDN_UNIVERSAL_STRING: {
DWORD num_ints = rdn_attr->Value.cbData / 4;
int* common_name =
reinterpret_cast<int*>(rdn_attr->Value.pbData);
for (DWORD k = 0; k < num_ints; ++k) {
if (common_name[k] == 0)
return true;
}
break;
}
default:
NOTREACHED();
break;
}
}
}
}
}
return false;
}
// Saves some information about the certificate chain chain_context in
// *verify_result. The caller MUST initialize *verify_result before calling
// this function.
void GetCertChainInfo(PCCERT_CHAIN_CONTEXT chain_context,
CertVerifyResult* verify_result) {
PCERT_SIMPLE_CHAIN first_chain = chain_context->rgpChain[0];
int num_elements = first_chain->cElement;
PCERT_CHAIN_ELEMENT* element = first_chain->rgpElement;
// Each chain starts with the end entity certificate (i = 0) and ends with
// the root CA certificate (i = num_elements - 1). Do not inspect the
// signature algorithm of the root CA certificate because the signature on
// the trust anchor is not important.
for (int i = 0; i < num_elements - 1; ++i) {
PCCERT_CONTEXT cert = element[i]->pCertContext;
const char* algorithm = cert->pCertInfo->SignatureAlgorithm.pszObjId;
if (strcmp(algorithm, szOID_RSA_MD5RSA) == 0) {
// md5WithRSAEncryption: 1.2.840.113549.1.1.4
verify_result->has_md5 = true;
if (i != 0)
verify_result->has_md5_ca = true;
} else if (strcmp(algorithm, szOID_RSA_MD2RSA) == 0) {
// md2WithRSAEncryption: 1.2.840.113549.1.1.2
verify_result->has_md2 = true;
if (i != 0)
verify_result->has_md2_ca = true;
} else if (strcmp(algorithm, szOID_RSA_MD4RSA) == 0) {
// md4WithRSAEncryption: 1.2.840.113549.1.1.3
verify_result->has_md4 = true;
}
}
}
///////////////////////////////////////////////////////////////////////////
//
// Functions used by X509Certificate::IsEV
//
///////////////////////////////////////////////////////////////////////////
// Constructs a certificate chain starting from the end certificate
// 'cert_context', matching any of the certificate policies.
//
// Returns the certificate chain context on success, or NULL on failure.
// The caller is responsible for freeing the certificate chain context with
// CertFreeCertificateChain.
PCCERT_CHAIN_CONTEXT ConstructCertChain(
PCCERT_CONTEXT cert_context,
const char* const* policies,
int num_policies) {
CERT_CHAIN_PARA chain_para;
memset(&chain_para, 0, sizeof(chain_para));
chain_para.cbSize = sizeof(chain_para);
chain_para.RequestedUsage.dwType = USAGE_MATCH_TYPE_AND;
chain_para.RequestedUsage.Usage.cUsageIdentifier = 0;
chain_para.RequestedUsage.Usage.rgpszUsageIdentifier = NULL; // LPSTR*
chain_para.RequestedIssuancePolicy.dwType = USAGE_MATCH_TYPE_OR;
chain_para.RequestedIssuancePolicy.Usage.cUsageIdentifier = num_policies;
chain_para.RequestedIssuancePolicy.Usage.rgpszUsageIdentifier =
const_cast<char**>(policies);
PCCERT_CHAIN_CONTEXT chain_context;
if (!CertGetCertificateChain(
NULL, // default chain engine, HCCE_CURRENT_USER
cert_context,
NULL, // current system time
cert_context->hCertStore, // search this store
&chain_para,
CERT_CHAIN_REVOCATION_CHECK_CHAIN_EXCLUDE_ROOT |
CERT_CHAIN_CACHE_END_CERT,
NULL, // reserved
&chain_context)) {
return NULL;
}
return chain_context;
}
// Decodes the cert's certificatePolicies extension into a CERT_POLICIES_INFO
// structure and stores it in *output.
void GetCertPoliciesInfo(PCCERT_CONTEXT cert,
scoped_ptr_malloc<CERT_POLICIES_INFO>* output) {
PCERT_EXTENSION extension = CertFindExtension(szOID_CERT_POLICIES,
cert->pCertInfo->cExtension,
cert->pCertInfo->rgExtension);
if (!extension)
return;
CRYPT_DECODE_PARA decode_para;
decode_para.cbSize = sizeof(decode_para);
decode_para.pfnAlloc = MyCryptAlloc;
decode_para.pfnFree = MyCryptFree;
CERT_POLICIES_INFO* policies_info = NULL;
DWORD policies_info_size = 0;
BOOL rv;
rv = CryptDecodeObjectEx(X509_ASN_ENCODING | PKCS_7_ASN_ENCODING,
szOID_CERT_POLICIES,
extension->Value.pbData,
extension->Value.cbData,
CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG,
&decode_para,
&policies_info,
&policies_info_size);
if (rv)
output->reset(policies_info);
}
// Returns true if the policy is in the array of CERT_POLICY_INFO in
// the CERT_POLICIES_INFO structure.
bool ContainsPolicy(const CERT_POLICIES_INFO* policies_info,
const char* policy) {
int num_policies = policies_info->cPolicyInfo;
for (int i = 0; i < num_policies; i++) {
if (!strcmp(policies_info->rgPolicyInfo[i].pszPolicyIdentifier, policy))
return true;
}
return false;
}
// Helper function to parse a principal from a WinInet description of that
// principal.
void ParsePrincipal(const std::string& description,
X509Certificate::Principal* principal) {
// The description of the principal is a string with each LDAP value on
// a separate line.
const std::string kDelimiters("\r\n");
std::vector<std::string> common_names, locality_names, state_names,
country_names;
// TODO(jcampan): add business_category and serial_number.
const std::string kPrefixes[] = { std::string("CN="),
std::string("L="),
std::string("S="),
std::string("C="),
std::string("STREET="),
std::string("O="),
std::string("OU="),
std::string("DC=") };
std::vector<std::string>* values[] = {
&common_names, &locality_names,
&state_names, &country_names,
&(principal->street_addresses),
&(principal->organization_names),
&(principal->organization_unit_names),
&(principal->domain_components) };
DCHECK(arraysize(kPrefixes) == arraysize(values));
StringTokenizer str_tok(description, kDelimiters);
while (str_tok.GetNext()) {
std::string entry = str_tok.token();
for (int i = 0; i < arraysize(kPrefixes); i++) {
if (!entry.compare(0, kPrefixes[i].length(), kPrefixes[i])) {
std::string value = entry.substr(kPrefixes[i].length());
// Remove enclosing double-quotes if any.
if (value.size() >= 2 &&
value[0] == '"' && value[value.size() - 1] == '"')
value = value.substr(1, value.size() - 2);
values[i]->push_back(value);
break;
}
}
}
// We don't expect to have more than one CN, L, S, and C.
std::vector<std::string>* single_value_lists[4] = {
&common_names, &locality_names, &state_names, &country_names };
std::string* single_values[4] = {
&principal->common_name, &principal->locality_name,
&principal->state_or_province_name, &principal->country_name };
for (int i = 0; i < arraysize(single_value_lists); ++i) {
int length = static_cast<int>(single_value_lists[i]->size());
DCHECK(single_value_lists[i]->size() <= 1);
if (single_value_lists[i]->size() > 0)
*(single_values[i]) = (*(single_value_lists[i]))[0];
}
}
} // namespace
void X509Certificate::Initialize() {
std::wstring subject_info;
std::wstring issuer_info;
DWORD name_size;
DCHECK(cert_handle_);
name_size = CertNameToStr(cert_handle_->dwCertEncodingType,
&cert_handle_->pCertInfo->Subject,
CERT_X500_NAME_STR | CERT_NAME_STR_CRLF_FLAG,
NULL, 0);
name_size = CertNameToStr(cert_handle_->dwCertEncodingType,
&cert_handle_->pCertInfo->Subject,
CERT_X500_NAME_STR | CERT_NAME_STR_CRLF_FLAG,
WriteInto(&subject_info, name_size), name_size);
name_size = CertNameToStr(cert_handle_->dwCertEncodingType,
&cert_handle_->pCertInfo->Issuer,
CERT_X500_NAME_STR | CERT_NAME_STR_CRLF_FLAG,
NULL, 0);
name_size = CertNameToStr(cert_handle_->dwCertEncodingType,
&cert_handle_->pCertInfo->Issuer,
CERT_X500_NAME_STR | CERT_NAME_STR_CRLF_FLAG,
WriteInto(&issuer_info, name_size), name_size);
ParsePrincipal(WideToUTF8(subject_info), &subject_);
ParsePrincipal(WideToUTF8(issuer_info), &issuer_);
valid_start_ = Time::FromFileTime(cert_handle_->pCertInfo->NotBefore);
valid_expiry_ = Time::FromFileTime(cert_handle_->pCertInfo->NotAfter);
fingerprint_ = CalculateFingerprint(cert_handle_);
// Store the certificate in the cache in case we need it later.
X509Certificate::Cache::GetInstance()->Insert(this);
}
// static
X509Certificate* X509Certificate::CreateFromPickle(const Pickle& pickle,
void** pickle_iter) {
const char* data;
int length;
if (!pickle.ReadData(pickle_iter, &data, &length))
return NULL;
OSCertHandle cert_handle = NULL;
if (!CertAddSerializedElementToStore(
NULL, // the cert won't be persisted in any cert store
reinterpret_cast<const BYTE*>(data), length,
CERT_STORE_ADD_USE_EXISTING, 0, CERT_STORE_CERTIFICATE_CONTEXT_FLAG,
NULL, reinterpret_cast<const void **>(&cert_handle)))
return NULL;
return CreateFromHandle(cert_handle, SOURCE_LONE_CERT_IMPORT);
}
void X509Certificate::Persist(Pickle* pickle) {
DCHECK(cert_handle_);
DWORD length;
if (!CertSerializeCertificateStoreElement(cert_handle_, 0,
NULL, &length)) {
NOTREACHED();
return;
}
BYTE* data = reinterpret_cast<BYTE*>(pickle->BeginWriteData(length));
if (!CertSerializeCertificateStoreElement(cert_handle_, 0,
data, &length)) {
NOTREACHED();
length = 0;
}
pickle->TrimWriteData(length);
}
void X509Certificate::GetDNSNames(std::vector<std::string>* dns_names) const {
dns_names->clear();
if (cert_handle_) {
scoped_ptr_malloc<CERT_ALT_NAME_INFO> alt_name_info;
GetCertSubjectAltName(cert_handle_, &alt_name_info);
CERT_ALT_NAME_INFO* alt_name = alt_name_info.get();
if (alt_name) {
int num_entries = alt_name->cAltEntry;
for (int i = 0; i < num_entries; i++) {
// dNSName is an ASN.1 IA5String representing a string of ASCII
// characters, so we can use WideToASCII here.
if (alt_name->rgAltEntry[i].dwAltNameChoice == CERT_ALT_NAME_DNS_NAME)
dns_names->push_back(
WideToASCII(alt_name->rgAltEntry[i].pwszDNSName));
}
}
}
if (dns_names->empty())
dns_names->push_back(subject_.common_name);
}
int X509Certificate::Verify(const std::string& hostname,
int flags,
CertVerifyResult* verify_result) const {
verify_result->Reset();
if (!cert_handle_)
return ERR_UNEXPECTED;
// Build and validate certificate chain.
CERT_CHAIN_PARA chain_para;
memset(&chain_para, 0, sizeof(chain_para));
chain_para.cbSize = sizeof(chain_para);
// TODO(wtc): consider requesting the usage szOID_PKIX_KP_SERVER_AUTH
// or szOID_SERVER_GATED_CRYPTO or szOID_SGC_NETSCAPE
chain_para.RequestedUsage.dwType = USAGE_MATCH_TYPE_AND;
chain_para.RequestedUsage.Usage.cUsageIdentifier = 0;
chain_para.RequestedUsage.Usage.rgpszUsageIdentifier = NULL; // LPSTR*
// We can set CERT_CHAIN_RETURN_LOWER_QUALITY_CONTEXTS to get more chains.
DWORD chain_flags = CERT_CHAIN_CACHE_END_CERT;
if (flags & VERIFY_REV_CHECKING_ENABLED) {
verify_result->cert_status |= CERT_STATUS_REV_CHECKING_ENABLED;
chain_flags |= CERT_CHAIN_REVOCATION_CHECK_CHAIN_EXCLUDE_ROOT;
} else {
chain_flags |= CERT_CHAIN_REVOCATION_CHECK_CACHE_ONLY;
// EV requires revocation checking.
flags &= ~VERIFY_EV_CERT;
}
PCCERT_CHAIN_CONTEXT chain_context;
if (!CertGetCertificateChain(
NULL, // default chain engine, HCCE_CURRENT_USER
cert_handle_,
NULL, // current system time
cert_handle_->hCertStore, // search this store
&chain_para,
chain_flags,
NULL, // reserved
&chain_context)) {
return MapSecurityError(GetLastError());
}
ScopedCertChainContext scoped_chain_context(chain_context);
GetCertChainInfo(chain_context, verify_result);
verify_result->cert_status |= MapCertChainErrorStatusToCertStatus(
chain_context->TrustStatus.dwErrorStatus);
// Treat certificates signed using broken signature algorithms as invalid.
if (verify_result->has_md4)
verify_result->cert_status |= CERT_STATUS_INVALID;
// Flag certificates signed using weak signature algorithms.
if (verify_result->has_md2)
verify_result->cert_status |= CERT_STATUS_WEAK_SIGNATURE_ALGORITHM;
// Flag certificates that have a Subject common name with a NULL character.
if (CertSubjectCommonNameHasNull(cert_handle_))
verify_result->cert_status |= CERT_STATUS_INVALID;
std::wstring wstr_hostname = ASCIIToWide(hostname);
SSL_EXTRA_CERT_CHAIN_POLICY_PARA extra_policy_para;
memset(&extra_policy_para, 0, sizeof(extra_policy_para));
extra_policy_para.cbSize = sizeof(extra_policy_para);
extra_policy_para.dwAuthType = AUTHTYPE_SERVER;
extra_policy_para.fdwChecks = 0;
extra_policy_para.pwszServerName =
const_cast<wchar_t*>(wstr_hostname.c_str());
CERT_CHAIN_POLICY_PARA policy_para;
memset(&policy_para, 0, sizeof(policy_para));
policy_para.cbSize = sizeof(policy_para);
policy_para.dwFlags = 0;
policy_para.pvExtraPolicyPara = &extra_policy_para;
CERT_CHAIN_POLICY_STATUS policy_status;
memset(&policy_status, 0, sizeof(policy_status));
policy_status.cbSize = sizeof(policy_status);
if (!CertVerifyCertificateChainPolicy(
CERT_CHAIN_POLICY_SSL,
chain_context,
&policy_para,
&policy_status)) {
return MapSecurityError(GetLastError());
}
if (policy_status.dwError) {
verify_result->cert_status |= MapNetErrorToCertStatus(
MapSecurityError(policy_status.dwError));
// CertVerifyCertificateChainPolicy reports only one error (in
// policy_status.dwError) if the certificate has multiple errors.
// CertGetCertificateChain doesn't report certificate name mismatch, so
// CertVerifyCertificateChainPolicy is the only function that can report
// certificate name mismatch.
//
// To prevent a potential certificate name mismatch from being hidden by
// some other certificate error, if we get any other certificate error,
// we call CertVerifyCertificateChainPolicy again, ignoring all other
// certificate errors. Both extra_policy_para.fdwChecks and
// policy_para.dwFlags allow us to ignore certificate errors, so we set
// them both.
if (policy_status.dwError != CERT_E_CN_NO_MATCH) {
const DWORD extra_ignore_flags =
0x00000080 | // SECURITY_FLAG_IGNORE_REVOCATION
0x00000100 | // SECURITY_FLAG_IGNORE_UNKNOWN_CA
0x00002000 | // SECURITY_FLAG_IGNORE_CERT_DATE_INVALID
0x00000200; // SECURITY_FLAG_IGNORE_WRONG_USAGE
extra_policy_para.fdwChecks = extra_ignore_flags;
const DWORD ignore_flags =
CERT_CHAIN_POLICY_IGNORE_ALL_NOT_TIME_VALID_FLAGS |
CERT_CHAIN_POLICY_IGNORE_INVALID_BASIC_CONSTRAINTS_FLAG |
CERT_CHAIN_POLICY_ALLOW_UNKNOWN_CA_FLAG |
CERT_CHAIN_POLICY_IGNORE_WRONG_USAGE_FLAG |
CERT_CHAIN_POLICY_IGNORE_INVALID_NAME_FLAG |
CERT_CHAIN_POLICY_IGNORE_INVALID_POLICY_FLAG |
CERT_CHAIN_POLICY_IGNORE_ALL_REV_UNKNOWN_FLAGS |
CERT_CHAIN_POLICY_ALLOW_TESTROOT_FLAG |
CERT_CHAIN_POLICY_TRUST_TESTROOT_FLAG |
CERT_CHAIN_POLICY_IGNORE_NOT_SUPPORTED_CRITICAL_EXT_FLAG |
CERT_CHAIN_POLICY_IGNORE_PEER_TRUST_FLAG;
policy_para.dwFlags = ignore_flags;
if (!CertVerifyCertificateChainPolicy(
CERT_CHAIN_POLICY_SSL,
chain_context,
&policy_para,
&policy_status)) {
return MapSecurityError(GetLastError());
}
if (policy_status.dwError) {
verify_result->cert_status |= MapNetErrorToCertStatus(
MapSecurityError(policy_status.dwError));
}
}
}
// TODO(wtc): Suppress CERT_STATUS_NO_REVOCATION_MECHANISM for now to be
// compatible with WinHTTP, which doesn't report this error (bug 3004).
verify_result->cert_status &= ~CERT_STATUS_NO_REVOCATION_MECHANISM;
if (IsCertStatusError(verify_result->cert_status))
return MapCertStatusToNetError(verify_result->cert_status);
// TODO(ukai): combine regular cert verification and EV cert verification.
if ((flags & VERIFY_EV_CERT) && VerifyEV())
verify_result->cert_status |= CERT_STATUS_IS_EV;
return OK;
}
// Returns true if the certificate is an extended-validation certificate.
//
// This function checks the certificatePolicies extensions of the
// certificates in the certificate chain according to Section 7 (pp. 11-12)
// of the EV Certificate Guidelines Version 1.0 at
// http://cabforum.org/EV_Certificate_Guidelines.pdf.
bool X509Certificate::VerifyEV() const {
DCHECK(cert_handle_);
net::EVRootCAMetadata* metadata = net::EVRootCAMetadata::GetInstance();
PCCERT_CHAIN_CONTEXT chain_context = ConstructCertChain(cert_handle_,
metadata->GetPolicyOIDs(), metadata->NumPolicyOIDs());
if (!chain_context)
return false;
ScopedCertChainContext scoped_chain_context(chain_context);
DCHECK(chain_context->cChain != 0);
// If the cert doesn't match any of the policies, the
// CERT_TRUST_IS_NOT_VALID_FOR_USAGE bit (0x10) in
// chain_context->TrustStatus.dwErrorStatus is set.
DWORD error_status = chain_context->TrustStatus.dwErrorStatus;
DWORD info_status = chain_context->TrustStatus.dwInfoStatus;
if (!chain_context->cChain || error_status != CERT_TRUST_NO_ERROR)
return false;
// Check the end certificate simple chain (chain_context->rgpChain[0]).
// If the end certificate's certificatePolicies extension contains the
// EV policy OID of the root CA, return true.
PCERT_CHAIN_ELEMENT* element = chain_context->rgpChain[0]->rgpElement;
int num_elements = chain_context->rgpChain[0]->cElement;
if (num_elements < 2)
return false;
// Look up the EV policy OID of the root CA.
PCCERT_CONTEXT root_cert = element[num_elements - 1]->pCertContext;
Fingerprint fingerprint = CalculateFingerprint(root_cert);
const char* ev_policy_oid = NULL;
if (!metadata->GetPolicyOID(fingerprint, &ev_policy_oid))
return false;
DCHECK(ev_policy_oid);
// Get the certificatePolicies extension of the end certificate.
PCCERT_CONTEXT end_cert = element[0]->pCertContext;
scoped_ptr_malloc<CERT_POLICIES_INFO> policies_info;
GetCertPoliciesInfo(end_cert, &policies_info);
if (!policies_info.get())
return false;
return ContainsPolicy(policies_info.get(), ev_policy_oid);
}
// static
X509Certificate::OSCertHandle X509Certificate::CreateOSCertHandleFromBytes(
const char* data, int length) {
OSCertHandle cert_handle = NULL;
if (!CertAddEncodedCertificateToStore(
NULL, // the cert won't be persisted in any cert store
X509_ASN_ENCODING,
reinterpret_cast<const BYTE*>(data), length,
CERT_STORE_ADD_USE_EXISTING,
&cert_handle))
return NULL;
return cert_handle;
}
// static
void X509Certificate::FreeOSCertHandle(OSCertHandle cert_handle) {
CertFreeCertificateContext(cert_handle);
}
// static
X509Certificate::Fingerprint X509Certificate::CalculateFingerprint(
OSCertHandle cert) {
DCHECK(NULL != cert->pbCertEncoded);
DCHECK(0 != cert->cbCertEncoded);
BOOL rv;
Fingerprint sha1;
DWORD sha1_size = sizeof(sha1.data);
rv = CryptHashCertificate(NULL, CALG_SHA1, 0, cert->pbCertEncoded,
cert->cbCertEncoded, sha1.data, &sha1_size);
DCHECK(rv && sha1_size == sizeof(sha1.data));
if (!rv)
memset(sha1.data, 0, sizeof(sha1.data));
return sha1;
}
} // namespace net