| Index: net/cert/sha256_legacy_support_openssl_win.cc
|
| diff --git a/net/cert/sha256_legacy_support_openssl_win.cc b/net/cert/sha256_legacy_support_openssl_win.cc
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..991f05196128bef71e888e04a39cc1e0cb674ea5
|
| --- /dev/null
|
| +++ b/net/cert/sha256_legacy_support_openssl_win.cc
|
| @@ -0,0 +1,154 @@
|
| +// Copyright 2014 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 <openssl/asn1.h>
|
| +#include <openssl/bytestring.h>
|
| +#include <openssl/evp.h>
|
| +#include <openssl/obj.h>
|
| +#include <openssl/x509.h>
|
| +
|
| +#include "base/logging.h"
|
| +#include "crypto/scoped_openssl_types.h"
|
| +#include "net/cert/sha256_legacy_support_win.h"
|
| +
|
| +namespace net {
|
| +
|
| +namespace sha256_interception {
|
| +
|
| +namespace {
|
| +
|
| +typedef crypto::ScopedOpenSSL<X509_ALGOR, X509_ALGOR_free>::Type
|
| + ScopedX509_ALGOR;
|
| +
|
| +// Parses |subject_signature| and writes the components into |*out_tbs_data|,
|
| +// |*out_algor|, and |*out_signature|. The BIT STRING in the signature must be
|
| +// a multiple of 8 bits. |*out_signature| will have the padding byte removed.
|
| +// It returns true on success and false on failure.
|
| +bool ParseSubjectSignature(const base::StringPiece& subject_signature,
|
| + CBS* out_tbs_data,
|
| + ScopedX509_ALGOR* out_algor,
|
| + CBS* out_signature) {
|
| + CBS cbs, sequence, tbs_data, algorithm, signature;
|
| + CBS_init(&cbs, reinterpret_cast<const uint8_t*>(subject_signature.data()),
|
| + subject_signature.size());
|
| + if (!CBS_get_asn1(&cbs, &sequence, CBS_ASN1_SEQUENCE) ||
|
| + CBS_len(&cbs) != 0 ||
|
| + !CBS_get_any_asn1_element(&sequence, &tbs_data, nullptr, nullptr) ||
|
| + !CBS_get_asn1_element(&sequence, &algorithm,
|
| + CBS_ASN1_SEQUENCE) ||
|
| + !CBS_get_asn1(&sequence, &signature, CBS_ASN1_BITSTRING) ||
|
| + CBS_len(&sequence) != 0) {
|
| + return false;
|
| + }
|
| +
|
| + // Decode the algorithm.
|
| + const uint8_t* ptr = CBS_data(&algorithm);
|
| + ScopedX509_ALGOR algor(d2i_X509_ALGOR(NULL, &ptr, CBS_len(&algorithm)));
|
| + if (!algor || ptr != CBS_data(&algorithm) + CBS_len(&algorithm))
|
| + return false;
|
| +
|
| + // An ASN.1 BIT STRING is encoded with a leading byte denoting the number of
|
| + // padding bits. All supported signature algorithms output octets, so the
|
| + // leading byte must be zero.
|
| + uint8_t padding;
|
| + if (!CBS_get_u8(&signature, &padding) || padding != 0)
|
| + return false;
|
| +
|
| + *out_tbs_data = tbs_data;
|
| + *out_algor = algor.Pass();
|
| + *out_signature = signature;
|
| + return true;
|
| +}
|
| +
|
| +} // namespace
|
| +
|
| +BOOL CryptVerifyCertificateSignatureExHook(
|
| + CryptVerifyCertificateSignatureExFunc original_func,
|
| + HCRYPTPROV_LEGACY provider,
|
| + DWORD encoding_type,
|
| + DWORD subject_type,
|
| + void* subject_data,
|
| + DWORD issuer_type,
|
| + void* issuer_data,
|
| + DWORD flags,
|
| + void* extra) {
|
| + CHECK(original_func);
|
| +
|
| + // Only intercept if the arguments are supported.
|
| + if (provider != NULL || (encoding_type != X509_ASN_ENCODING) ||
|
| + !IsSupportedSubjectType(subject_type) || subject_data == NULL ||
|
| + !IsSupportedIssuerType(issuer_type) || issuer_data == NULL) {
|
| + return original_func(provider, encoding_type, subject_type, subject_data,
|
| + issuer_type, issuer_data, flags, extra);
|
| + }
|
| +
|
| + base::StringPiece subject_signature =
|
| + GetSubjectSignature(subject_type, subject_data);
|
| + bool should_intercept = false;
|
| +
|
| + // Parse out the data, AlgorithmIdentifier, and signature.
|
| + CBS tbs_data, signature;
|
| + ScopedX509_ALGOR algor;
|
| + if (ParseSubjectSignature(subject_signature, &tbs_data, &algor,
|
| + &signature)) {
|
| + // If the signature algorithm is RSA with one of the SHA-2 algorithms
|
| + // supported by BoringSSL (excluding SHA-224, which is pointless), then
|
| + // defer to the BoringSSL implementation. Otherwise, fall back and let the
|
| + // OS handle it (e.g. in case there are any algorithm policies in effect).
|
| + int nid = OBJ_obj2nid(algor->algorithm);
|
| + if (nid == NID_sha256WithRSAEncryption ||
|
| + nid == NID_sha384WithRSAEncryption ||
|
| + nid == NID_sha512WithRSAEncryption) {
|
| + should_intercept = true;
|
| + }
|
| + }
|
| +
|
| + if (!should_intercept) {
|
| + return original_func(provider, encoding_type, subject_type, subject_data,
|
| + issuer_type, issuer_data, flags, extra);
|
| + }
|
| +
|
| + // Rather than attempting to synthesize an EVP_PKEY by hand, just force the
|
| + // OS to do an ASN.1 encoding and then decode it back into BoringSSL. This
|
| + // is silly for performance, but safest for consistency.
|
| + PCERT_PUBLIC_KEY_INFO issuer_public_key =
|
| + GetIssuerPublicKey(issuer_type, issuer_data);
|
| + if (!issuer_public_key) {
|
| + SetLastError(static_cast<DWORD>(NTE_BAD_ALGID));
|
| + return FALSE;
|
| + }
|
| +
|
| + uint8_t* issuer_spki_data = NULL;
|
| + DWORD issuer_spki_len = 0;
|
| + if (!CryptEncodeObjectEx(X509_ASN_ENCODING, X509_PUBLIC_KEY_INFO,
|
| + issuer_public_key, CRYPT_ENCODE_ALLOC_FLAG, NULL,
|
| + &issuer_spki_data, &issuer_spki_len)) {
|
| + return FALSE;
|
| + }
|
| +
|
| + const uint8_t* ptr = issuer_spki_data;
|
| + crypto::ScopedEVP_PKEY pubkey(d2i_PUBKEY(NULL, &ptr, issuer_spki_len));
|
| + if (!pubkey.get() || ptr != issuer_spki_data + issuer_spki_len) {
|
| + ::LocalFree(issuer_spki_data);
|
| + SetLastError(static_cast<DWORD>(NTE_BAD_ALGID));
|
| + return FALSE;
|
| + }
|
| + ::LocalFree(issuer_spki_data);
|
| +
|
| + crypto::ScopedEVP_MD_CTX md_ctx(EVP_MD_CTX_create());
|
| + if (!EVP_DigestVerifyInitFromAlgorithm(md_ctx.get(), algor.get(),
|
| + pubkey.get()) ||
|
| + !EVP_DigestVerifyUpdate(md_ctx.get(), CBS_data(&tbs_data),
|
| + CBS_len(&tbs_data)) ||
|
| + !EVP_DigestVerifyFinal(md_ctx.get(), CBS_data(&signature),
|
| + CBS_len(&signature))) {
|
| + SetLastError(static_cast<DWORD>(NTE_BAD_SIGNATURE));
|
| + return FALSE;
|
| + }
|
| + return TRUE;
|
| +}
|
| +
|
| +} // namespace sha256_interception
|
| +
|
| +} // namespace net
|
|
|