Add error information to VerifySignedData().

net/cert/internal/verify_signed_data.cc

 // Copyright 2015 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/cert/internal/verify_signed_data.h"
 
 #include <openssl/bytestring.h>
 #include <openssl/digest.h>
 #include <openssl/ec.h>
 #include <openssl/ec_key.h>
 #include <openssl/evp.h>
 #include <openssl/rsa.h>
 
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "crypto/openssl_util.h"
 #include "crypto/scoped_openssl_types.h"
+#include "net/cert/internal/cert_errors.h"
 #include "net/cert/internal/signature_algorithm.h"
 #include "net/cert/internal/signature_policy.h"
 #include "net/der/input.h"
 #include "net/der/parse_values.h"
 #include "net/der/parser.h"
 
 namespace net {
 
 namespace {
 
+DEFINE_CERT_ERROR_TYPE(kUnacceptableSignatureAlgorithm,
+                       "Unacceptable signature algorithm");
+DEFINE_CERT_ERROR_TYPE(kUnacceptableRsaModulusLength,
+                       "Unacceptable modulus length for RSA key");
+DEFINE_CERT_ERROR_TYPE(kUnacceptableEcdsaCurve,
+                       "Unacceptable curve for ECDSA key");
+DEFINE_CERT_ERROR_TYPE(kSignatureVerificationFailed,
+                       "Signature verification failed");
+
 // Converts a DigestAlgorithm to an equivalent EVP_MD*.
 WARN_UNUSED_RESULT bool GetDigest(DigestAlgorithm digest, const EVP_MD** out) {
   *out = nullptr;
 
   switch (digest) {
     case DigestAlgorithm::Sha1:
       *out = EVP_sha1();
       break;
     case DigestAlgorithm::Sha256:
       *out = EVP_sha256();
@@ skipping 99 matching lines @@
 // of parameters for rsaEncryption. Whereas RFC 5912 says they must be absent,
 // RFC 3279 says they must be NULL:
 //
 //     The rsaEncryption OID is intended to be used in the algorithm field
 //     of a value of type AlgorithmIdentifier.  The parameters field MUST
 //     have ASN.1 type NULL for this algorithm identifier.
 //
 // Following RFC 3279 in this case.
 WARN_UNUSED_RESULT bool ParseRsaKeyFromSpki(const der::Input& public_key_spki,
                                             crypto::ScopedEVP_PKEY* pkey,
-                                            const SignaturePolicy* policy) {
+                                            const SignaturePolicy* policy,
+                                            CertErrors* errors) {
+  // TODO(crbug.com/634443): Add more specific errors.
   if (!ImportPkeyFromSpki(public_key_spki, EVP_PKEY_RSA, pkey))
     return false;
 
   // Extract the modulus length from the key.
   crypto::ScopedRSA rsa(EVP_PKEY_get1_RSA(pkey->get()));
   if (!rsa)
     return false;
   unsigned int modulus_length_bits = BN_num_bits(rsa->n);
 
-  return policy->IsAcceptableModulusLengthForRsa(modulus_length_bits);
+  if (!policy->IsAcceptableModulusLengthForRsa(modulus_length_bits, errors)) {
+    errors->Add(kUnacceptableRsaModulusLength);
+    return false;
+  }
+
+  return true;
 }
 
 // Does signature verification using either RSA or ECDSA.
 WARN_UNUSED_RESULT bool DoVerify(const SignatureAlgorithm& algorithm,
                                  const der::Input& signed_data,
                                  const der::BitString& signature_value,
                                  EVP_PKEY* public_key) {
   DCHECK(algorithm.algorithm() == SignatureAlgorithmId::RsaPkcs1 ||
          algorithm.algorithm() == SignatureAlgorithmId::RsaPss ||
          algorithm.algorithm() == SignatureAlgorithmId::Ecdsa);
@@ skipping 71 matching lines @@
 //     NamedCurve CURVE ::= {
 //     { ID secp192r1 } | { ID sect163k1 } | { ID sect163r2 } |
 //     { ID secp224r1 } | { ID sect233k1 } | { ID sect233r1 } |
 //     { ID secp256r1 } | { ID sect283k1 } | { ID sect283r1 } |
 //     { ID secp384r1 } | { ID sect409k1 } | { ID sect409r1 } |
 //     { ID secp521r1 } | { ID sect571k1 } | { ID sect571r1 },
 //     ... -- Extensible
 //     }
 WARN_UNUSED_RESULT bool ParseEcKeyFromSpki(const der::Input& public_key_spki,
                                            crypto::ScopedEVP_PKEY* pkey,
-                                           const SignaturePolicy* policy) {
+                                           const SignaturePolicy* policy,
+                                           CertErrors* errors) {
+  // TODO(crbug.com/634443): Add more specific errors.
   if (!ImportPkeyFromSpki(public_key_spki, EVP_PKEY_EC, pkey))
     return false;
 
   // Extract the curve name.
   crypto::ScopedEC_KEY ec(EVP_PKEY_get1_EC_KEY(pkey->get()));
   if (!ec.get())
     return false;  // Unexpected.
   int curve_nid = EC_GROUP_get_curve_name(EC_KEY_get0_group(ec.get()));
 
-  return policy->IsAcceptableCurveForEcdsa(curve_nid);
+  if (!policy->IsAcceptableCurveForEcdsa(curve_nid, errors)) {
+    errors->Add(kUnacceptableEcdsaCurve);
+    return false;
+  }
+
+  return true;
 }
 
 }  // namespace
 
 bool VerifySignedData(const SignatureAlgorithm& signature_algorithm,
                       const der::Input& signed_data,
                       const der::BitString& signature_value,
                       const der::Input& public_key_spki,
-                      const SignaturePolicy* policy) {
-  if (!policy->IsAcceptableSignatureAlgorithm(signature_algorithm))
+                      const SignaturePolicy* policy,
+                      CertErrors* errors) {
+  if (!policy->IsAcceptableSignatureAlgorithm(signature_algorithm, errors)) {
+    errors->Add(kUnacceptableSignatureAlgorithm);
     return false;
+  }
 
   crypto::ScopedEVP_PKEY public_key;
 
   // Parse the SPKI to an EVP_PKEY appropriate for the signature algorithm.
   switch (signature_algorithm.algorithm()) {
     case SignatureAlgorithmId::RsaPkcs1:
     case SignatureAlgorithmId::RsaPss:
-      if (!ParseRsaKeyFromSpki(public_key_spki, &public_key, policy))
+      if (!ParseRsaKeyFromSpki(public_key_spki, &public_key, policy, errors))
         return false;
       break;
     case SignatureAlgorithmId::Ecdsa:
-      if (!ParseEcKeyFromSpki(public_key_spki, &public_key, policy))
+      if (!ParseEcKeyFromSpki(public_key_spki, &public_key, policy, errors))
         return false;
       break;
   }
 
-  return DoVerify(signature_algorithm, signed_data, signature_value,
-                  public_key.get());
+  if (!DoVerify(signature_algorithm, signed_data, signature_value,
+                public_key.get())) {
+    errors->Add(kSignatureVerificationFailed);
+    return false;
+  }
+
+  return true;
 }
 
 }  // namespace net