Move crypto files out of base, to a top level directory.

crypto/signature_verifier_unittest.cc

+// 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 "crypto/signature_verifier.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+TEST(SignatureVerifierTest, BasicTest) {
+  // The input data in this test comes from real certificates.
+  //
+  // tbs_certificate ("to-be-signed certificate", the part of a certificate
+  // that is signed), signature_algorithm, and algorithm come from the
+  // certificate of bugs.webkit.org.
+  //
+  // public_key_info comes from the certificate of the issuer, Go Daddy Secure
+  // Certification Authority.
+  //
+  // The bytes in the array initializers are formatted to expose the DER
+  // encoding of the ASN.1 structures.
+
+  // The data that is signed is the following ASN.1 structure:
+  //    TBSCertificate  ::=  SEQUENCE  {
+  //        ...  -- omitted, not important
+  //        }
+  const uint8 tbs_certificate[1017] = {
+    0x30, 0x82, 0x03, 0xf5,  // a SEQUENCE of length 1013 (0x3f5)
+    0xa0, 0x03, 0x02, 0x01, 0x02, 0x02, 0x03, 0x43, 0xdd, 0x63, 0x30, 0x0d,
+    0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x05, 0x05,
+    0x00, 0x30, 0x81, 0xca, 0x31, 0x0b, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04,
+    0x06, 0x13, 0x02, 0x55, 0x53, 0x31, 0x10, 0x30, 0x0e, 0x06, 0x03, 0x55,
+    0x04, 0x08, 0x13, 0x07, 0x41, 0x72, 0x69, 0x7a, 0x6f, 0x6e, 0x61, 0x31,
+    0x13, 0x30, 0x11, 0x06, 0x03, 0x55, 0x04, 0x07, 0x13, 0x0a, 0x53, 0x63,
+    0x6f, 0x74, 0x74, 0x73, 0x64, 0x61, 0x6c, 0x65, 0x31, 0x1a, 0x30, 0x18,
+    0x06, 0x03, 0x55, 0x04, 0x0a, 0x13, 0x11, 0x47, 0x6f, 0x44, 0x61, 0x64,
+    0x64, 0x79, 0x2e, 0x63, 0x6f, 0x6d, 0x2c, 0x20, 0x49, 0x6e, 0x63, 0x2e,
+    0x31, 0x33, 0x30, 0x31, 0x06, 0x03, 0x55, 0x04, 0x0b, 0x13, 0x2a, 0x68,
+    0x74, 0x74, 0x70, 0x3a, 0x2f, 0x2f, 0x63, 0x65, 0x72, 0x74, 0x69, 0x66,
+    0x69, 0x63, 0x61, 0x74, 0x65, 0x73, 0x2e, 0x67, 0x6f, 0x64, 0x61, 0x64,
+    0x64, 0x79, 0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x72, 0x65, 0x70, 0x6f, 0x73,
+    0x69, 0x74, 0x6f, 0x72, 0x79, 0x31, 0x30, 0x30, 0x2e, 0x06, 0x03, 0x55,
+    0x04, 0x03, 0x13, 0x27, 0x47, 0x6f, 0x20, 0x44, 0x61, 0x64, 0x64, 0x79,
+    0x20, 0x53, 0x65, 0x63, 0x75, 0x72, 0x65, 0x20, 0x43, 0x65, 0x72, 0x74,
+    0x69, 0x66, 0x69, 0x63, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x20, 0x41, 0x75,
+    0x74, 0x68, 0x6f, 0x72, 0x69, 0x74, 0x79, 0x31, 0x11, 0x30, 0x0f, 0x06,
+    0x03, 0x55, 0x04, 0x05, 0x13, 0x08, 0x30, 0x37, 0x39, 0x36, 0x39, 0x32,
+    0x38, 0x37, 0x30, 0x1e, 0x17, 0x0d, 0x30, 0x38, 0x30, 0x33, 0x31, 0x38,
+    0x32, 0x33, 0x33, 0x35, 0x31, 0x39, 0x5a, 0x17, 0x0d, 0x31, 0x31, 0x30,
+    0x33, 0x31, 0x38, 0x32, 0x33, 0x33, 0x35, 0x31, 0x39, 0x5a, 0x30, 0x79,
+    0x31, 0x0b, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x06, 0x13, 0x02, 0x55,
+    0x53, 0x31, 0x13, 0x30, 0x11, 0x06, 0x03, 0x55, 0x04, 0x08, 0x13, 0x0a,
+    0x43, 0x61, 0x6c, 0x69, 0x66, 0x6f, 0x72, 0x6e, 0x69, 0x61, 0x31, 0x12,
+    0x30, 0x10, 0x06, 0x03, 0x55, 0x04, 0x07, 0x13, 0x09, 0x43, 0x75, 0x70,
+    0x65, 0x72, 0x74, 0x69, 0x6e, 0x6f, 0x31, 0x13, 0x30, 0x11, 0x06, 0x03,
+    0x55, 0x04, 0x0a, 0x13, 0x0a, 0x41, 0x70, 0x70, 0x6c, 0x65, 0x20, 0x49,
+    0x6e, 0x63, 0x2e, 0x31, 0x15, 0x30, 0x13, 0x06, 0x03, 0x55, 0x04, 0x0b,
+    0x13, 0x0c, 0x4d, 0x61, 0x63, 0x20, 0x4f, 0x53, 0x20, 0x46, 0x6f, 0x72,
+    0x67, 0x65, 0x31, 0x15, 0x30, 0x13, 0x06, 0x03, 0x55, 0x04, 0x03, 0x13,
+    0x0c, 0x2a, 0x2e, 0x77, 0x65, 0x62, 0x6b, 0x69, 0x74, 0x2e, 0x6f, 0x72,
+    0x67, 0x30, 0x81, 0x9f, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
+    0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x81, 0x8d, 0x00, 0x30,
+    0x81, 0x89, 0x02, 0x81, 0x81, 0x00, 0xa7, 0x62, 0x79, 0x41, 0xda, 0x28,
+    0xf2, 0xc0, 0x4f, 0xe0, 0x25, 0xaa, 0xa1, 0x2e, 0x3b, 0x30, 0x94, 0xb5,
+    0xc9, 0x26, 0x3a, 0x1b, 0xe2, 0xd0, 0xcc, 0xa2, 0x95, 0xe2, 0x91, 0xc0,
+    0xf0, 0x40, 0x9e, 0x27, 0x6e, 0xbd, 0x6e, 0xde, 0x7c, 0xb6, 0x30, 0x5c,
+    0xb8, 0x9b, 0x01, 0x2f, 0x92, 0x04, 0xa1, 0xef, 0x4a, 0xb1, 0x6c, 0xb1,
+    0x7e, 0x8e, 0xcd, 0xa6, 0xf4, 0x40, 0x73, 0x1f, 0x2c, 0x96, 0xad, 0xff,
+    0x2a, 0x6d, 0x0e, 0xba, 0x52, 0x84, 0x83, 0xb0, 0x39, 0xee, 0xc9, 0x39,
+    0xdc, 0x1e, 0x34, 0xd0, 0xd8, 0x5d, 0x7a, 0x09, 0xac, 0xa9, 0xee, 0xca,
+    0x65, 0xf6, 0x85, 0x3a, 0x6b, 0xee, 0xe4, 0x5c, 0x5e, 0xf8, 0xda, 0xd1,
+    0xce, 0x88, 0x47, 0xcd, 0x06, 0x21, 0xe0, 0xb9, 0x4b, 0xe4, 0x07, 0xcb,
+    0x57, 0xdc, 0xca, 0x99, 0x54, 0xf7, 0x0e, 0xd5, 0x17, 0x95, 0x05, 0x2e,
+    0xe9, 0xb1, 0x02, 0x03, 0x01, 0x00, 0x01, 0xa3, 0x82, 0x01, 0xce, 0x30,
+    0x82, 0x01, 0xca, 0x30, 0x09, 0x06, 0x03, 0x55, 0x1d, 0x13, 0x04, 0x02,
+    0x30, 0x00, 0x30, 0x0b, 0x06, 0x03, 0x55, 0x1d, 0x0f, 0x04, 0x04, 0x03,
+    0x02, 0x05, 0xa0, 0x30, 0x1d, 0x06, 0x03, 0x55, 0x1d, 0x25, 0x04, 0x16,
+    0x30, 0x14, 0x06, 0x08, 0x2b, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x01,
+    0x06, 0x08, 0x2b, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x02, 0x30, 0x57,
+    0x06, 0x03, 0x55, 0x1d, 0x1f, 0x04, 0x50, 0x30, 0x4e, 0x30, 0x4c, 0xa0,
+    0x4a, 0xa0, 0x48, 0x86, 0x46, 0x68, 0x74, 0x74, 0x70, 0x3a, 0x2f, 0x2f,
+    0x63, 0x65, 0x72, 0x74, 0x69, 0x66, 0x69, 0x63, 0x61, 0x74, 0x65, 0x73,
+    0x2e, 0x67, 0x6f, 0x64, 0x61, 0x64, 0x64, 0x79, 0x2e, 0x63, 0x6f, 0x6d,
+    0x2f, 0x72, 0x65, 0x70, 0x6f, 0x73, 0x69, 0x74, 0x6f, 0x72, 0x79, 0x2f,
+    0x67, 0x6f, 0x64, 0x61, 0x64, 0x64, 0x79, 0x65, 0x78, 0x74, 0x65, 0x6e,
+    0x64, 0x65, 0x64, 0x69, 0x73, 0x73, 0x75, 0x69, 0x6e, 0x67, 0x33, 0x2e,
+    0x63, 0x72, 0x6c, 0x30, 0x52, 0x06, 0x03, 0x55, 0x1d, 0x20, 0x04, 0x4b,
+    0x30, 0x49, 0x30, 0x47, 0x06, 0x0b, 0x60, 0x86, 0x48, 0x01, 0x86, 0xfd,
+    0x6d, 0x01, 0x07, 0x17, 0x02, 0x30, 0x38, 0x30, 0x36, 0x06, 0x08, 0x2b,
+    0x06, 0x01, 0x05, 0x05, 0x07, 0x02, 0x01, 0x16, 0x2a, 0x68, 0x74, 0x74,
+    0x70, 0x3a, 0x2f, 0x2f, 0x63, 0x65, 0x72, 0x74, 0x69, 0x66, 0x69, 0x63,
+    0x61, 0x74, 0x65, 0x73, 0x2e, 0x67, 0x6f, 0x64, 0x61, 0x64, 0x64, 0x79,
+    0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x72, 0x65, 0x70, 0x6f, 0x73, 0x69, 0x74,
+    0x6f, 0x72, 0x79, 0x30, 0x7f, 0x06, 0x08, 0x2b, 0x06, 0x01, 0x05, 0x05,
+    0x07, 0x01, 0x01, 0x04, 0x73, 0x30, 0x71, 0x30, 0x23, 0x06, 0x08, 0x2b,
+    0x06, 0x01, 0x05, 0x05, 0x07, 0x30, 0x01, 0x86, 0x17, 0x68, 0x74, 0x74,
+    0x70, 0x3a, 0x2f, 0x2f, 0x6f, 0x63, 0x73, 0x70, 0x2e, 0x67, 0x6f, 0x64,
+    0x61, 0x64, 0x64, 0x79, 0x2e, 0x63, 0x6f, 0x6d, 0x30, 0x4a, 0x06, 0x08,
+    0x2b, 0x06, 0x01, 0x05, 0x05, 0x07, 0x30, 0x02, 0x86, 0x3e, 0x68, 0x74,
+    0x74, 0x70, 0x3a, 0x2f, 0x2f, 0x63, 0x65, 0x72, 0x74, 0x69, 0x66, 0x69,
+    0x63, 0x61, 0x74, 0x65, 0x73, 0x2e, 0x67, 0x6f, 0x64, 0x61, 0x64, 0x64,
+    0x79, 0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x72, 0x65, 0x70, 0x6f, 0x73, 0x69,
+    0x74, 0x6f, 0x72, 0x79, 0x2f, 0x67, 0x64, 0x5f, 0x69, 0x6e, 0x74, 0x65,
+    0x72, 0x6d, 0x65, 0x64, 0x69, 0x61, 0x74, 0x65, 0x2e, 0x63, 0x72, 0x74,
+    0x30, 0x1d, 0x06, 0x03, 0x55, 0x1d, 0x0e, 0x04, 0x16, 0x04, 0x14, 0x48,
+    0xdf, 0x60, 0x32, 0xcc, 0x89, 0x01, 0xb6, 0xdc, 0x2f, 0xe3, 0x73, 0xb5,
+    0x9c, 0x16, 0x58, 0x32, 0x68, 0xa9, 0xc3, 0x30, 0x1f, 0x06, 0x03, 0x55,
+    0x1d, 0x23, 0x04, 0x18, 0x30, 0x16, 0x80, 0x14, 0xfd, 0xac, 0x61, 0x32,
+    0x93, 0x6c, 0x45, 0xd6, 0xe2, 0xee, 0x85, 0x5f, 0x9a, 0xba, 0xe7, 0x76,
+    0x99, 0x68, 0xcc, 0xe7, 0x30, 0x23, 0x06, 0x03, 0x55, 0x1d, 0x11, 0x04,
+    0x1c, 0x30, 0x1a, 0x82, 0x0c, 0x2a, 0x2e, 0x77, 0x65, 0x62, 0x6b, 0x69,
+    0x74, 0x2e, 0x6f, 0x72, 0x67, 0x82, 0x0a, 0x77, 0x65, 0x62, 0x6b, 0x69,
+    0x74, 0x2e, 0x6f, 0x72, 0x67
+  };
+
+  // The signature algorithm is specified as the following ASN.1 structure:
+  //    AlgorithmIdentifier  ::=  SEQUENCE  {
+  //        algorithm               OBJECT IDENTIFIER,
+  //        parameters              ANY DEFINED BY algorithm OPTIONAL  }
+  //
+  const uint8 signature_algorithm[15] = {
+    0x30, 0x0d,  // a SEQUENCE of length 13 (0xd)
+      0x06, 0x09,  // an OBJECT IDENTIFIER of length 9
+        // 1.2.840.113549.1.1.5 - sha1WithRSAEncryption
+        0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x05,
+      0x05, 0x00,  // a NULL of length 0
+  };
+
+  // RSA signature, a big integer in the big-endian byte order.
+  const uint8 signature[256] = {
+    0x1e, 0x6a, 0xe7, 0xe0, 0x4f, 0xe7, 0x4d, 0xd0, 0x69, 0x7c, 0xf8, 0x8f,
+    0x99, 0xb4, 0x18, 0x95, 0x36, 0x24, 0x0f, 0x0e, 0xa3, 0xea, 0x34, 0x37,
+    0xf4, 0x7d, 0xd5, 0x92, 0x35, 0x53, 0x72, 0x76, 0x3f, 0x69, 0xf0, 0x82,
+    0x56, 0xe3, 0x94, 0x7a, 0x1d, 0x1a, 0x81, 0xaf, 0x9f, 0xc7, 0x43, 0x01,
+    0x64, 0xd3, 0x7c, 0x0d, 0xc8, 0x11, 0x4e, 0x4a, 0xe6, 0x1a, 0xc3, 0x01,
+    0x74, 0xe8, 0x35, 0x87, 0x5c, 0x61, 0xaa, 0x8a, 0x46, 0x06, 0xbe, 0x98,
+    0x95, 0x24, 0x9e, 0x01, 0xe3, 0xe6, 0xa0, 0x98, 0xee, 0x36, 0x44, 0x56,
+    0x8d, 0x23, 0x9c, 0x65, 0xea, 0x55, 0x6a, 0xdf, 0x66, 0xee, 0x45, 0xe8,
+    0xa0, 0xe9, 0x7d, 0x9a, 0xba, 0x94, 0xc5, 0xc8, 0xc4, 0x4b, 0x98, 0xff,
+    0x9a, 0x01, 0x31, 0x6d, 0xf9, 0x2b, 0x58, 0xe7, 0xe7, 0x2a, 0xc5, 0x4d,
+    0xbb, 0xbb, 0xcd, 0x0d, 0x70, 0xe1, 0xad, 0x03, 0xf5, 0xfe, 0xf4, 0x84,
+    0x71, 0x08, 0xd2, 0xbc, 0x04, 0x7b, 0x26, 0x1c, 0xa8, 0x0f, 0x9c, 0xd8,
+    0x12, 0x6a, 0x6f, 0x2b, 0x67, 0xa1, 0x03, 0x80, 0x9a, 0x11, 0x0b, 0xe9,
+    0xe0, 0xb5, 0xb3, 0xb8, 0x19, 0x4e, 0x0c, 0xa4, 0xd9, 0x2b, 0x3b, 0xc2,
+    0xca, 0x20, 0xd3, 0x0c, 0xa4, 0xff, 0x93, 0x13, 0x1f, 0xfc, 0xba, 0x94,
+    0x93, 0x8c, 0x64, 0x15, 0x2e, 0x28, 0xa9, 0x55, 0x8c, 0x2c, 0x48, 0xd3,
+    0xd3, 0xc1, 0x50, 0x69, 0x19, 0xe8, 0x34, 0xd3, 0xf1, 0x04, 0x9f, 0x0a,
+    0x7a, 0x21, 0x87, 0xbf, 0xb9, 0x59, 0x37, 0x2e, 0xf4, 0x71, 0xa5, 0x3e,
+    0xbe, 0xcd, 0x70, 0x83, 0x18, 0xf8, 0x8a, 0x72, 0x85, 0x45, 0x1f, 0x08,
+    0x01, 0x6f, 0x37, 0xf5, 0x2b, 0x7b, 0xea, 0xb9, 0x8b, 0xa3, 0xcc, 0xfd,
+    0x35, 0x52, 0xdd, 0x66, 0xde, 0x4f, 0x30, 0xc5, 0x73, 0x81, 0xb6, 0xe8,
+    0x3c, 0xd8, 0x48, 0x8a
+  };
+
+  // The public key is specified as the following ASN.1 structure:
+  //   SubjectPublicKeyInfo  ::=  SEQUENCE  {
+  //       algorithm            AlgorithmIdentifier,
+  //       subjectPublicKey     BIT STRING  }
+  const uint8 public_key_info[294] = {
+    0x30, 0x82, 0x01, 0x22,  // a SEQUENCE of length 290 (0x122)
+      // algorithm
+      0x30, 0x0d,  // a SEQUENCE of length 13
+        0x06, 0x09,  // an OBJECT IDENTIFIER of length 9
+          0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01,
+        0x05, 0x00,  // a NULL of length 0
+      // subjectPublicKey
+      0x03, 0x82, 0x01, 0x0f,  // a BIT STRING of length 271 (0x10f)
+        0x00,  // number of unused bits
+        0x30, 0x82, 0x01, 0x0a,  // a SEQUENCE of length 266 (0x10a)
+          // modulus
+          0x02, 0x82, 0x01, 0x01,  // an INTEGER of length 257 (0x101)
+            0x00, 0xc4, 0x2d, 0xd5, 0x15, 0x8c, 0x9c, 0x26, 0x4c, 0xec,
+            0x32, 0x35, 0xeb, 0x5f, 0xb8, 0x59, 0x01, 0x5a, 0xa6, 0x61,
+            0x81, 0x59, 0x3b, 0x70, 0x63, 0xab, 0xe3, 0xdc, 0x3d, 0xc7,
+            0x2a, 0xb8, 0xc9, 0x33, 0xd3, 0x79, 0xe4, 0x3a, 0xed, 0x3c,
+            0x30, 0x23, 0x84, 0x8e, 0xb3, 0x30, 0x14, 0xb6, 0xb2, 0x87,
+            0xc3, 0x3d, 0x95, 0x54, 0x04, 0x9e, 0xdf, 0x99, 0xdd, 0x0b,
+            0x25, 0x1e, 0x21, 0xde, 0x65, 0x29, 0x7e, 0x35, 0xa8, 0xa9,
+            0x54, 0xeb, 0xf6, 0xf7, 0x32, 0x39, 0xd4, 0x26, 0x55, 0x95,
+            0xad, 0xef, 0xfb, 0xfe, 0x58, 0x86, 0xd7, 0x9e, 0xf4, 0x00,
+            0x8d, 0x8c, 0x2a, 0x0c, 0xbd, 0x42, 0x04, 0xce, 0xa7, 0x3f,
+            0x04, 0xf6, 0xee, 0x80, 0xf2, 0xaa, 0xef, 0x52, 0xa1, 0x69,
+            0x66, 0xda, 0xbe, 0x1a, 0xad, 0x5d, 0xda, 0x2c, 0x66, 0xea,
+            0x1a, 0x6b, 0xbb, 0xe5, 0x1a, 0x51, 0x4a, 0x00, 0x2f, 0x48,
+            0xc7, 0x98, 0x75, 0xd8, 0xb9, 0x29, 0xc8, 0xee, 0xf8, 0x66,
+            0x6d, 0x0a, 0x9c, 0xb3, 0xf3, 0xfc, 0x78, 0x7c, 0xa2, 0xf8,
+            0xa3, 0xf2, 0xb5, 0xc3, 0xf3, 0xb9, 0x7a, 0x91, 0xc1, 0xa7,
+            0xe6, 0x25, 0x2e, 0x9c, 0xa8, 0xed, 0x12, 0x65, 0x6e, 0x6a,
+            0xf6, 0x12, 0x44, 0x53, 0x70, 0x30, 0x95, 0xc3, 0x9c, 0x2b,
+            0x58, 0x2b, 0x3d, 0x08, 0x74, 0x4a, 0xf2, 0xbe, 0x51, 0xb0,
+            0xbf, 0x87, 0xd0, 0x4c, 0x27, 0x58, 0x6b, 0xb5, 0x35, 0xc5,
+            0x9d, 0xaf, 0x17, 0x31, 0xf8, 0x0b, 0x8f, 0xee, 0xad, 0x81,
+            0x36, 0x05, 0x89, 0x08, 0x98, 0xcf, 0x3a, 0xaf, 0x25, 0x87,
+            0xc0, 0x49, 0xea, 0xa7, 0xfd, 0x67, 0xf7, 0x45, 0x8e, 0x97,
+            0xcc, 0x14, 0x39, 0xe2, 0x36, 0x85, 0xb5, 0x7e, 0x1a, 0x37,
+            0xfd, 0x16, 0xf6, 0x71, 0x11, 0x9a, 0x74, 0x30, 0x16, 0xfe,
+            0x13, 0x94, 0xa3, 0x3f, 0x84, 0x0d, 0x4f,
+          // public exponent
+          0x02, 0x03,  // an INTEGER of length 3
+             0x01, 0x00, 0x01
+  };
+
+  // We use the signature verifier to perform four signature verification
+  // tests.
+  crypto::SignatureVerifier verifier;
+  bool ok;
+
+  // Test 1: feed all of the data to the verifier at once (a single
+  // VerifyUpdate call).
+  ok = verifier.VerifyInit(signature_algorithm,
+                           sizeof(signature_algorithm),
+                           signature, sizeof(signature),
+                           public_key_info, sizeof(public_key_info));
+  EXPECT_TRUE(ok);
+  verifier.VerifyUpdate(tbs_certificate, sizeof(tbs_certificate));
+  ok = verifier.VerifyFinal();
+  EXPECT_TRUE(ok);
+
+  // Test 2: feed the data to the verifier in three parts (three VerifyUpdate
+  // calls).
+  ok = verifier.VerifyInit(signature_algorithm,
+                           sizeof(signature_algorithm),
+                           signature, sizeof(signature),
+                           public_key_info, sizeof(public_key_info));
+  EXPECT_TRUE(ok);
+  verifier.VerifyUpdate(tbs_certificate,       256);
+  verifier.VerifyUpdate(tbs_certificate + 256, 256);
+  verifier.VerifyUpdate(tbs_certificate + 512, sizeof(tbs_certificate) - 512);
+  ok = verifier.VerifyFinal();
+  EXPECT_TRUE(ok);
+
+  // Test 3: verify the signature with incorrect data.
+  uint8 bad_tbs_certificate[sizeof(tbs_certificate)];
+  memcpy(bad_tbs_certificate, tbs_certificate, sizeof(tbs_certificate));
+  bad_tbs_certificate[10] += 1;  // Corrupt one byte of the data.
+  ok = verifier.VerifyInit(signature_algorithm,
+                           sizeof(signature_algorithm),
+                           signature, sizeof(signature),
+                           public_key_info, sizeof(public_key_info));
+  EXPECT_TRUE(ok);
+  verifier.VerifyUpdate(bad_tbs_certificate, sizeof(bad_tbs_certificate));
+  ok = verifier.VerifyFinal();
+
+  // Purify disables digital signature verification, causing the Windows
+  // CryptoAPI function CryptVerifySignature to always succeed.  So we can't
+  // check the signature verification results of the negative tests when
+  // running inside Purify.  See http://crbug.com/10031.
+#ifndef PURIFY
+  EXPECT_FALSE(ok);
+#endif
+
+  // Test 4: verify a bad signature.
+  uint8 bad_signature[sizeof(signature)];
+  memcpy(bad_signature, signature, sizeof(signature));
+  bad_signature[10] += 1;  // Corrupt one byte of the signature.
+  ok = verifier.VerifyInit(signature_algorithm,
+                           sizeof(signature_algorithm),
+                           bad_signature, sizeof(bad_signature),
+                           public_key_info, sizeof(public_key_info));
+
+  // A crypto library (e.g., NSS) may detect that the signature is corrupted
+  // and cause VerifyInit to return false, so it is fine for 'ok' to be false.
+  if (ok) {
+    verifier.VerifyUpdate(tbs_certificate, sizeof(tbs_certificate));
+    ok = verifier.VerifyFinal();
+#ifndef PURIFY
+    EXPECT_FALSE(ok);
+#endif
+  }
+}