OpenSSL/NSS implementation of ProofVerfifier.

net/quic/crypto/proof_test.cc

Index: net/quic/crypto/proof_test.cc
diff --git a/net/quic/crypto/proof_test.cc b/net/quic/crypto/proof_test.cc
index 3423b50fcc293e411ff265ab42af3ff00e099fea..5191c06b5fd09095eac400e15ae403335f5935d0 100644
--- a/net/quic/crypto/proof_test.cc
+++ b/net/quic/crypto/proof_test.cc
@@ -2,9 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/files/file_path.h"
+#include "net/base/net_errors.h"
+#include "net/base/test_completion_callback.h"
+#include "net/base/test_data_directory.h"
+#include "net/cert/x509_certificate.h"
 #include "net/quic/crypto/proof_source.h"
 #include "net/quic/crypto/proof_verifier.h"
 #include "net/quic/test_tools/crypto_test_utils.h"
+#include "net/test/cert_test_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using std::string;
@@ -24,7 +30,7 @@ TEST(Proof, Verify) {
   const string hostname = "test.example.com";
   const vector<string>* certs;
   const vector<string>* first_certs;
-  string error_details, signature, first_signature;
+  string signature, first_signature;
 
   ASSERT_TRUE(source->GetProof(hostname, server_config, &first_certs,
                                &first_signature));
@@ -34,25 +40,339 @@ TEST(Proof, Verify) {
   ASSERT_EQ(first_certs, certs);
   ASSERT_EQ(signature, first_signature);
 
-  ASSERT_TRUE(verifier->VerifyProof(hostname, server_config, *certs, signature,
-                                    &error_details));
-  ASSERT_FALSE(verifier->VerifyProof("foo.com", server_config, *certs,
-                                     signature, &error_details));
-  ASSERT_FALSE(
-      verifier->VerifyProof(hostname, server_config.substr(1, string::npos),
-                            *certs, signature, &error_details));
+  int rv;
+  TestCompletionCallback callback;
+  rv = verifier->VerifyProof(hostname, server_config, *certs, signature,
+                             callback.callback());
+  if (rv == ERR_IO_PENDING)
+    rv = callback.WaitForResult();
+  ASSERT_EQ(OK, rv);
+  ASSERT_EQ("", verifier->error_details());
+
+  rv = verifier->VerifyProof("foo.com", server_config, *certs,
+                             signature, callback.callback());
+  if (rv == ERR_IO_PENDING)
+    rv = callback.WaitForResult();
+  ASSERT_EQ(ERR_FAILED, rv);
+  ASSERT_NE("", verifier->error_details());
+
+  rv = verifier->VerifyProof(hostname, server_config.substr(1, string::npos),
+                             *certs, signature, callback.callback());
+  if (rv == ERR_IO_PENDING)
+    rv = callback.WaitForResult();
+  ASSERT_EQ(ERR_FAILED, rv);
+  ASSERT_NE("", verifier->error_details());
+
   const string corrupt_signature = "1" + signature;
-  ASSERT_FALSE(verifier->VerifyProof(hostname, server_config, *certs,
-                                     corrupt_signature, &error_details));
+  rv = verifier->VerifyProof(hostname, server_config, *certs,
+                             corrupt_signature, callback.callback());
+  if (rv == ERR_IO_PENDING)
+    rv = callback.WaitForResult();
+  ASSERT_EQ(ERR_FAILED, rv);
+  ASSERT_NE("", verifier->error_details());
 
   vector<string> wrong_certs;
   for (size_t i = 1; i < certs->size(); i++) {
     wrong_certs.push_back((*certs)[i]);
   }
-  ASSERT_FALSE(verifier->VerifyProof("foo.com", server_config, wrong_certs,
-                                     signature, &error_details));
+  rv = verifier->VerifyProof("foo.com", server_config, wrong_certs,
+                             signature, callback.callback());
+  if (rv == ERR_IO_PENDING)
+    rv = callback.WaitForResult();
+  ASSERT_EQ(ERR_FAILED, rv);
+  ASSERT_NE("", verifier->error_details());
 #endif  // 0
 }
 
+static string PEMCertFileToDER(const string& file_name) {
+  base::FilePath certs_dir = GetTestCertsDirectory();
+  scoped_refptr<X509Certificate> cert =
+      ImportCertFromFile(certs_dir, file_name);
+  CHECK_NE(static_cast<X509Certificate*>(NULL), cert);
+
+  string der_bytes;
+  CHECK(X509Certificate::GetDEREncoded(cert->os_cert_handle(), &der_bytes));
+  return der_bytes;
+}
+
+// A known answer test that allows us to test ProofVerifier without a working
+// ProofSource.
+TEST(Proof, VerifyRSAKnownAnswerTest) {
+  // These sample signatures were generated by running the Proof.Verify test
+  // and dumping the bytes of the |signature| output of ProofSource::GetProof().
+#if 0
+  // sLen = hLen

[agl, 2013/07/01 16:23:18]

The #if 0 block should probably either be removed, or the comment should be
expanded to explain why it's being kept around.

[wtc, 2013/07/02 00:56:38]

ramant: please feel free to just delete the #if 0 block. We can come back
to this code review to recover these sample signatures when we change the
sLen parameter for RSA-PSS signatures.

[ramant (doing other things), 2013/07/02 14:19:50]

Added a comment.

Done.

+  static const unsigned char signature_data_0[] = {
+    0x9e, 0xe6, 0x74, 0x3b, 0x8f, 0xb8, 0x66, 0x77, 0x57, 0x09,
+    0x8a, 0x04, 0xe9, 0xf0, 0x7c, 0x91, 0xa9, 0x5c, 0xe9, 0xdf,
+    0x12, 0x4d, 0x23, 0x82, 0x8c, 0x29, 0x72, 0x7f, 0xc2, 0x20,
+    0xa7, 0xb3, 0xe5, 0xbc, 0xcf, 0x3c, 0x0d, 0x8f, 0xae, 0x46,
+    0x6a, 0xb9, 0xee, 0x0c, 0xe1, 0x13, 0x21, 0xc0, 0x7e, 0x45,
+    0x24, 0x24, 0x4b, 0x72, 0x43, 0x5e, 0xc4, 0x0d, 0xdf, 0x6c,
+    0xd8, 0xaa, 0x35, 0x97, 0x05, 0x40, 0x76, 0xd3, 0x2c, 0xee,
+    0x82, 0x16, 0x6a, 0x43, 0xf9, 0xa2, 0xd0, 0x41, 0x3c, 0xed,
+    0x3f, 0x40, 0x10, 0x95, 0xc7, 0xa9, 0x1f, 0x04, 0xdb, 0xd5,
+    0x98, 0x9f, 0xe2, 0xbf, 0x77, 0x3d, 0xc9, 0x9a, 0xaf, 0xf7,
+    0xef, 0x63, 0x0b, 0x7d, 0xc8, 0x37, 0xda, 0x37, 0x23, 0x88,
+    0x78, 0xc8, 0x8b, 0xf5, 0xb9, 0x36, 0x5d, 0x72, 0x1f, 0xfc,
+    0x14, 0xff, 0xa7, 0x81, 0x27, 0x49, 0xae, 0xe1,
+  };
+  static const unsigned char signature_data_1[] = {
+    0x5e, 0xc2, 0xab, 0x6b, 0x16, 0xe6, 0x55, 0xf3, 0x16, 0x46,
+    0x35, 0xdc, 0xcc, 0xde, 0xd0, 0xbd, 0x6c, 0x66, 0xb2, 0x3d,
+    0xd3, 0x14, 0x78, 0xed, 0x47, 0x55, 0xfb, 0xdb, 0xe1, 0x7d,
+    0xbf, 0x31, 0xf6, 0xf4, 0x10, 0x4c, 0x8d, 0x22, 0x17, 0xaa,
+    0xe1, 0x85, 0xc7, 0x96, 0x4c, 0x42, 0xfb, 0xf4, 0x63, 0x53,
+    0x8a, 0x79, 0x01, 0x63, 0x48, 0xa8, 0x3a, 0xbc, 0xc9, 0xd2,
+    0xf5, 0xec, 0xe9, 0x09, 0x71, 0xaf, 0xce, 0x34, 0x56, 0xe5,
+    0x00, 0xbe, 0xee, 0x3c, 0x1c, 0xc4, 0xa0, 0x07, 0xd5, 0x77,
+    0xb8, 0x83, 0x57, 0x7d, 0x1a, 0xc9, 0xd0, 0xc0, 0x59, 0x9a,
+    0x88, 0x19, 0x3f, 0xb9, 0xf0, 0x45, 0x37, 0xc3, 0x00, 0x8b,
+    0xb3, 0x89, 0xf4, 0x89, 0x07, 0xa9, 0xc3, 0x26, 0xbf, 0x81,
+    0xaf, 0x6b, 0x47, 0xbc, 0x16, 0x55, 0x37, 0x0a, 0xbe, 0x0e,
+    0xc5, 0x75, 0x3f, 0x3d, 0x8e, 0xe8, 0x44, 0xe3,
+  };
+  static const unsigned char signature_data_2[] = {
+    0x8e, 0x5c, 0x78, 0x63, 0x74, 0x99, 0x2e, 0x96, 0xc0, 0x14,
+    0x8d, 0xb5, 0x13, 0x74, 0xa3, 0xa4, 0xe0, 0x43, 0x3e, 0x85,
+    0xba, 0x8f, 0x3c, 0x5e, 0x14, 0x64, 0x0e, 0x5e, 0xff, 0x89,
+    0x88, 0x8a, 0x65, 0xe2, 0xa2, 0x79, 0xe4, 0xe9, 0x3a, 0x7f,
+    0xf6, 0x9d, 0x3d, 0xe2, 0xb0, 0x8a, 0x35, 0x55, 0xed, 0x21,
+    0xee, 0x20, 0xd8, 0x8a, 0x60, 0x47, 0xca, 0x52, 0x54, 0x91,
+    0x99, 0x69, 0x8d, 0x16, 0x34, 0x69, 0xe1, 0x46, 0x56, 0x67,
+    0x5f, 0x50, 0xf0, 0x94, 0xe7, 0x8b, 0xf2, 0x6a, 0x73, 0x0f,
+    0x30, 0x30, 0xde, 0x59, 0xdc, 0xc7, 0xfe, 0xb6, 0x83, 0xe1,
+    0x86, 0x1d, 0x88, 0xd3, 0x2f, 0x2f, 0x74, 0x68, 0xbd, 0x6c,
+    0xd1, 0x46, 0x76, 0x06, 0xa9, 0xd4, 0x03, 0x3f, 0xda, 0x7d,
+    0xa7, 0xff, 0x48, 0xe4, 0xb4, 0x42, 0x06, 0xac, 0x19, 0x12,
+    0xe6, 0x05, 0xae, 0xbe, 0x29, 0x94, 0x8f, 0x99,
+  };
+#else
+  // sLen = special value -2 used by OpenSSL.
+  static const unsigned char signature_data_0[] = {
+    0x4c, 0x68, 0x3c, 0xc2, 0x1f, 0x31, 0x73, 0xa5, 0x29, 0xd3,
+    0x56, 0x75, 0xb1, 0xbf, 0xbd, 0x31, 0x17, 0xfb, 0x2e, 0x24,
+    0xb3, 0xc4, 0x0d, 0xfa, 0x56, 0xb8, 0x65, 0x94, 0x12, 0x38,
+    0x6e, 0xff, 0xb3, 0x10, 0x2e, 0xf8, 0x5c, 0xc1, 0x21, 0x9d,
+    0x29, 0x0c, 0x3a, 0x0a, 0x1a, 0xbf, 0x6b, 0x1c, 0x63, 0x77,
+    0xf7, 0x86, 0xd3, 0xa4, 0x36, 0xf2, 0xb1, 0x6f, 0xac, 0xc3,
+    0x23, 0x8d, 0xda, 0xe6, 0xd5, 0x83, 0xba, 0xdf, 0x28, 0x3e,
+    0x7f, 0x4e, 0x79, 0xfc, 0xba, 0xdb, 0xf7, 0xd0, 0x4b, 0xad,
+    0x79, 0xd0, 0xeb, 0xcf, 0xfa, 0x6e, 0x84, 0x44, 0x7a, 0x26,
+    0xb1, 0x29, 0xa3, 0x08, 0xa8, 0x63, 0xfd, 0xed, 0x85, 0xff,
+    0x9a, 0xe6, 0x79, 0x8b, 0xb6, 0x81, 0x13, 0x2c, 0xde, 0xe2,
+    0xd8, 0x31, 0x29, 0xa4, 0xe0, 0x1b, 0x75, 0x2d, 0x8a, 0xf8,
+    0x27, 0x55, 0xbc, 0xc7, 0x3b, 0x1e, 0xc1, 0x42,
+  };
+  static const unsigned char signature_data_1[] = {
+    0xbb, 0xd1, 0x17, 0x43, 0xf3, 0x42, 0x16, 0xe9, 0xf9, 0x76,
+    0xe6, 0xe3, 0xaa, 0x50, 0x47, 0x5f, 0x93, 0xb6, 0x7d, 0x35,
+    0x03, 0x49, 0x0a, 0x07, 0x61, 0xd5, 0xf1, 0x9c, 0x6b, 0xaf,
+    0xaa, 0xd7, 0x64, 0xe4, 0x0a, 0x0c, 0xab, 0x97, 0xfb, 0x4e,
+    0x5c, 0x14, 0x08, 0xf6, 0xb9, 0xa9, 0x1d, 0xa9, 0xf8, 0x6d,
+    0xb0, 0x2b, 0x2a, 0x0e, 0xc4, 0xd0, 0xd2, 0xe9, 0x96, 0x4f,
+    0x44, 0x70, 0x90, 0x46, 0xb9, 0xd5, 0x89, 0x72, 0xb9, 0xa8,
+    0xe4, 0xfb, 0x88, 0xbc, 0x69, 0x7f, 0xc9, 0xdc, 0x84, 0x87,
+    0x18, 0x21, 0x9b, 0xde, 0x22, 0x33, 0xde, 0x16, 0x3f, 0xe6,
+    0xfd, 0x27, 0x56, 0xd3, 0xa4, 0x97, 0x91, 0x65, 0x1a, 0xe7,
+    0x5e, 0x80, 0x9a, 0xbf, 0xbf, 0x1a, 0x29, 0x8a, 0xbe, 0xa2,
+    0x8c, 0x9c, 0x23, 0xf4, 0xcb, 0xba, 0x79, 0x31, 0x28, 0xab,
+    0x77, 0x94, 0x92, 0xb2, 0xc2, 0x35, 0xb2, 0xfa,
+  };
+  static const unsigned char signature_data_2[] = {
+    0x7e, 0x17, 0x01, 0xcb, 0x76, 0x9e, 0x9f, 0xce, 0xeb, 0x66,
+    0x3e, 0xaa, 0xc9, 0x36, 0x5b, 0x7e, 0x48, 0x25, 0x99, 0xf8,
+    0x0d, 0xe1, 0xa8, 0x48, 0x93, 0x3c, 0xe8, 0x97, 0x2e, 0x98,
+    0xd6, 0x73, 0x0f, 0xd0, 0x74, 0x9c, 0x17, 0xef, 0xee, 0xf8,
+    0x0e, 0x2a, 0x27, 0x3f, 0xc6, 0x55, 0xc6, 0xb9, 0xfe, 0x17,
+    0xcc, 0xeb, 0x5d, 0xa1, 0xdc, 0xbd, 0x64, 0xd9, 0x5e, 0xec,
+    0x57, 0x9d, 0xc3, 0xdc, 0x11, 0xbf, 0x23, 0x02, 0x58, 0xc4,
+    0xf1, 0x18, 0xc1, 0x6f, 0x3f, 0xef, 0x18, 0x4d, 0xa6, 0x1e,
+    0xe8, 0x25, 0x32, 0x8f, 0x92, 0x1e, 0xad, 0xbc, 0xbe, 0xde,
+    0x83, 0x2a, 0x92, 0xd5, 0x59, 0x6f, 0xe4, 0x95, 0x6f, 0xe6,
+    0xb1, 0xf9, 0xaf, 0x3f, 0xdb, 0x69, 0x6f, 0xae, 0xa6, 0x36,
+    0xd2, 0x50, 0x81, 0x78, 0x41, 0x13, 0x2c, 0x65, 0x9c, 0x9e,
+    0xf4, 0xd2, 0xd5, 0x58, 0x5b, 0x8b, 0x87, 0xcf,
+  };
+#endif
+
+  scoped_ptr<ProofVerifier> verifier(
+      CryptoTestUtils::ProofVerifierForTesting());
+
+  const string server_config = "server config bytes";
+  const string hostname = "test.example.com";
+
+  vector<string> certs(2);
+  certs[0] = PEMCertFileToDER("test.example.com.crt");
+  certs[1] = PEMCertFileToDER("intermediate.crt");
+
+  // Signatures are nondeterministic, so we test multiple signatures on the
+  // same server_config.
+  vector<string> signatures(3);
+  signatures[0].assign(reinterpret_cast<const char*>(signature_data_0),
+                       sizeof(signature_data_0));
+  signatures[1].assign(reinterpret_cast<const char*>(signature_data_1),
+                       sizeof(signature_data_1));
+  signatures[2].assign(reinterpret_cast<const char*>(signature_data_2),
+                       sizeof(signature_data_2));
+
+  for (size_t i = 0; i < signatures.size(); i++) {
+    const string& signature = signatures[i];
+    int rv;
+    TestCompletionCallback callback;
+    rv = verifier->VerifyProof(hostname, server_config, certs, signature,
+                               callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();

[wtc, 2013/07/02 00:56:38]

Nit: this can be rewritten more compactly as
  rv = callback.GetResult(rv);

[ramant (doing other things), 2013/07/02 14:19:50]

Done.

+    ASSERT_EQ(OK, rv);
+    ASSERT_EQ("", verifier->error_details());

[wtc, 2013/07/02 00:56:38]

Nit: add blank lines between these tests. Specifically, add a blank line
after each ASSERT_EQ("", verifier->error_details()).

[ramant (doing other things), 2013/07/02 14:19:50]

Done.

+    rv = verifier->VerifyProof("foo.com", server_config, certs, signature,
+                               callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(ERR_FAILED, rv);
+    ASSERT_NE("", verifier->error_details());
+    rv = verifier->VerifyProof(hostname, server_config.substr(1, string::npos),
+                               certs, signature, callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(ERR_FAILED, rv);
+    ASSERT_NE("", verifier->error_details());
+
+    const string corrupt_signature = "1" + signature;
+    rv = verifier->VerifyProof(hostname, server_config, certs,
+                               corrupt_signature, callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(ERR_FAILED, rv);
+    ASSERT_NE("", verifier->error_details());
+
+    vector<string> wrong_certs;
+    for (size_t i = 1; i < certs.size(); i++) {
+      wrong_certs.push_back(certs[i]);
+    }
+    rv = verifier->VerifyProof("foo.com", server_config, wrong_certs, signature,
+                               callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(ERR_FAILED, rv);
+    ASSERT_NE("", verifier->error_details());
+  }
+}
+
+// A known answer test that allows us to test ProofVerifier without a working
+// ProofSource.
+TEST(Proof, VerifyECDSAKnownAnswerTest) {
+  // These sample signatures were generated by running the Proof.Verify test
+  // (modified to use ECDSA for signing proofs) and dumping the bytes of the
+  // |signature| output of ProofSource::GetProof().
+  static const unsigned char signature_data_0[] = {
+    0x30, 0x45, 0x02, 0x20, 0x15, 0xb7, 0x9f, 0xe3, 0xd9, 0x7a,
+    0x3c, 0x3b, 0x18, 0xb0, 0xdb, 0x60, 0x23, 0x56, 0xa0, 0x06,
+    0x4e, 0x70, 0xa3, 0xf7, 0x4b, 0xe5, 0x0d, 0x69, 0xf0, 0x35,
+    0x8c, 0xae, 0xb5, 0x54, 0x32, 0xe9, 0x02, 0x21, 0x00, 0xf7,
+    0xe3, 0x06, 0x99, 0x16, 0x56, 0x7e, 0xab, 0x33, 0x53, 0x0d,
+    0xde, 0xbe, 0xef, 0x6d, 0xb0, 0xc7, 0xa6, 0x63, 0xaf, 0x8d,
+    0xab, 0x34, 0xa9, 0xc0, 0x63, 0x88, 0x47, 0x17, 0x4c, 0x4c,
+    0x04,
+  };
+  static const unsigned char signature_data_1[] = {
+    0x30, 0x44, 0x02, 0x20, 0x69, 0x60, 0x55, 0xbb, 0x11, 0x93,
+    0x6a, 0xdc, 0x9b, 0x61, 0x2c, 0x60, 0x19, 0xbc, 0x15, 0x55,
+    0xcf, 0xf2, 0x8e, 0x2e, 0x27, 0x0b, 0x69, 0xef, 0x33, 0x25,
+    0x1e, 0x5d, 0x8c, 0x00, 0x11, 0xef, 0x02, 0x20, 0x0c, 0x26,
+    0xfe, 0x0b, 0x06, 0x8f, 0xe8, 0xe2, 0x02, 0x63, 0xe5, 0x43,
+    0x0d, 0xc9, 0x80, 0x4d, 0xe9, 0x6f, 0x6e, 0x18, 0xdb, 0xb0,
+    0x04, 0x2a, 0x45, 0x37, 0x1a, 0x60, 0x0e, 0xc6, 0xc4, 0x8f,
+  };
+  static const unsigned char signature_data_2[] = {
+    0x30, 0x45, 0x02, 0x21, 0x00, 0xd5, 0x43, 0x36, 0x60, 0x50,
+    0xce, 0xe0, 0x00, 0x51, 0x02, 0x84, 0x95, 0x51, 0x47, 0xaf,
+    0xe4, 0xf9, 0xe1, 0x23, 0xae, 0x21, 0xb4, 0x98, 0xd1, 0xa3,
+    0x5f, 0x3b, 0xf3, 0x6a, 0x65, 0x44, 0x6b, 0x02, 0x20, 0x30,
+    0x7e, 0xb4, 0xea, 0xf0, 0xda, 0xdb, 0xbd, 0x38, 0xb9, 0x7a,
+    0x5d, 0x12, 0x04, 0x0e, 0xc2, 0xf0, 0xb1, 0x0e, 0x25, 0xf8,
+    0x0a, 0x27, 0xa3, 0x16, 0x94, 0xac, 0x1e, 0xb8, 0x6e, 0x00,
+    0x05,
+  };
+
+  scoped_ptr<ProofVerifier> verifier(
+      CryptoTestUtils::ProofVerifierForTesting());
+
+  const string server_config = "server config bytes";
+  const string hostname = "test.example.com";
+
+  vector<string> certs(2);
+  certs[0] = PEMCertFileToDER("test_ecc.example.com.crt");
+  certs[1] = PEMCertFileToDER("intermediate.crt");
+
+  // Signatures are nondeterministic, so we test multiple signatures on the
+  // same server_config.
+  vector<string> signatures(3);
+  signatures[0].assign(reinterpret_cast<const char*>(signature_data_0),
+                       sizeof(signature_data_0));
+  signatures[1].assign(reinterpret_cast<const char*>(signature_data_1),
+                       sizeof(signature_data_1));
+  signatures[2].assign(reinterpret_cast<const char*>(signature_data_2),
+                       sizeof(signature_data_2));
+
+  for (size_t i = 0; i < signatures.size(); i++) {
+    const string& signature = signatures[i];
+    int rv;
+    TestCompletionCallback callback;
+    rv = verifier->VerifyProof(hostname, server_config, certs, signature,
+                               callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(OK, rv);
+    ASSERT_EQ("", verifier->error_details());
+
+    rv = verifier->VerifyProof("foo.com", server_config, certs,
+                               signature, callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(ERR_FAILED, rv);
+    ASSERT_NE("", verifier->error_details());
+
+    rv = verifier->VerifyProof(hostname, server_config.substr(1, string::npos),
+                               certs, signature, callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(ERR_FAILED, rv);
+    ASSERT_NE("", verifier->error_details());
+
+    // An ECDSA signature is DER-encoded. Corrupt the last byte so that the
+    // signature can still be DER-decoded correctly.
+    string corrupt_signature = signature;
+    corrupt_signature[corrupt_signature.size() - 1] += 1;
+    rv = verifier->VerifyProof(hostname, server_config, certs,
+                               corrupt_signature, callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(ERR_FAILED, rv);
+    ASSERT_NE("", verifier->error_details());
+
+    // Prepending a "1" makes the DER invalid.
+    const string bad_der_signature1 = "1" + signature;
+    rv = verifier->VerifyProof(hostname, server_config, certs,
+                               bad_der_signature1, callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(ERR_FAILED, rv);
+    ASSERT_NE("", verifier->error_details());
+
+    vector<string> wrong_certs;
+    for (size_t i = 1; i < certs.size(); i++) {
+      wrong_certs.push_back(certs[i]);
+    }
+    rv = verifier->VerifyProof("foo.com", server_config, wrong_certs, signature,
+                               callback.callback());
+    if (rv == ERR_IO_PENDING)
+      rv = callback.WaitForResult();
+    ASSERT_EQ(ERR_FAILED, rv);
+    ASSERT_NE("", verifier->error_details());
+  }
+}
+
 }  // namespace test
 }  // namespace net