Add a utility method to convert SPKI from DER to JWK, so far implemented only for EC P256v1 (which …

net/cert/jwk_serializer_unittest.cc

+// Copyright (c) 2013 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/jwk_serializer.h"
+
+#include "base/base64.h"
+#include "base/values.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace net {
+
+// This is the ASN.1 prefix for a P-256 public key. Specifically it's:
+// SEQUENCE
+//   SEQUENCE
+//     OID id-ecPublicKey
+//     OID prime256v1
+//   BIT STRING, length 66, 0 trailing bits: 0x04
+//
+// The 0x04 in the BIT STRING is the prefix for an uncompressed, X9.62
+// public key. Following that are the two field elements as 32-byte,
+// big-endian numbers, as required by the Channel ID.
+static const unsigned char kP256SpkiPrefix[] = {
+    0x30, 0x59, 0x30, 0x13, 0x06, 0x07, 0x2a, 0x86,
+    0x48, 0xce, 0x3d, 0x02, 0x01, 0x06, 0x08, 0x2a,
+    0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07, 0x03,
+    0x42, 0x00, 0x04
+};
+static const unsigned int kEcPointSize = 32U;

[wtc, 2013/08/08 19:26:09]

The constant name kEcPointSize is confusing because an EC point consists
of the x and y coordinates, but 32U is the size of just one coordinate.

+
+// This is a valid P-256 public key.
+static const unsigned char kSpkiEc[] = {
+    0x30, 0x59, 0x30, 0x13, 0x06, 0x07, 0x2a, 0x86,
+    0x48, 0xce, 0x3d, 0x02, 0x01, 0x06, 0x08, 0x2a,
+    0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07, 0x03,
+    0x42, 0x00, 0x04,
+    0x29, 0x5d, 0x6e, 0xfe, 0x33, 0x77, 0x26, 0xea,
+    0x5b, 0xa4, 0xe6, 0x1b, 0x34, 0x6e, 0x7b, 0xa0,
+    0xa3, 0x8f, 0x33, 0x49, 0xa0, 0x9c, 0xae, 0x98,
+    0xbd, 0x46, 0x0d, 0xf6, 0xd4, 0x5a, 0xdc, 0x8a,
+    0x1f, 0x8a, 0xb2, 0x20, 0x51, 0xb7, 0xd2, 0x87,
+    0x0d, 0x53, 0x7e, 0x5d, 0x94, 0xa3, 0xe0, 0x34,
+    0x16, 0xa1, 0xcc, 0x10, 0x48, 0xcd, 0x70, 0x9c,
+    0x05, 0xd3, 0xd2, 0xca, 0xdf, 0x44, 0x2f, 0xf4
+};
+
+// This is a P-256 public key with 0 X and Y values.
+static const unsigned char kSpkiEcWithZeroXY[] = {
+    0x30, 0x59, 0x30, 0x13, 0x06, 0x07, 0x2a, 0x86,
+    0x48, 0xce, 0x3d, 0x02, 0x01, 0x06, 0x08, 0x2a,
+    0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07, 0x03,
+    0x42, 0x00, 0x04,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+};
+
+#if !defined(USE_OPENSSL)
+
+TEST(JwkSerializerNSSTest, ConvertSpkiFromDerToJwkEc) {
+  base::StringPiece spki;
+  base::DictionaryValue public_key_jwk;
+
+  EXPECT_FALSE(JwkSerializer::ConvertSpkiFromDerToJwk(spki, &public_key_jwk));
+  EXPECT_TRUE(public_key_jwk.empty());
+
+  // Test the result of a "normal" point on this curve.
+  spki.set(reinterpret_cast<const char*>(kSpkiEc), sizeof(kSpkiEc));
+  EXPECT_TRUE(JwkSerializer::ConvertSpkiFromDerToJwk(spki, &public_key_jwk));
+
+  std::string string_value;
+  EXPECT_TRUE(public_key_jwk.GetString("alg", &string_value));
+  EXPECT_STREQ("EC", string_value.c_str());
+  EXPECT_TRUE(public_key_jwk.GetString("crv", &string_value));
+  EXPECT_STREQ("P-256", string_value.c_str());
+
+  EXPECT_TRUE(public_key_jwk.GetString("x", &string_value));
+  std::string decoded_coordinate;
+  EXPECT_TRUE(base::Base64Decode(string_value, &decoded_coordinate));
+  EXPECT_EQ(kEcPointSize, decoded_coordinate.size());
+  EXPECT_EQ(0,
+            memcmp(decoded_coordinate.data(),
+                   kSpkiEc + sizeof(kP256SpkiPrefix),
+                   kEcPointSize));
+
+  EXPECT_TRUE(public_key_jwk.GetString("y", &string_value));
+  EXPECT_TRUE(base::Base64Decode(string_value, &decoded_coordinate));
+  EXPECT_EQ(kEcPointSize, decoded_coordinate.size());
+  EXPECT_EQ(0,
+            memcmp(decoded_coordinate.data(),
+                  kSpkiEc + sizeof(kP256SpkiPrefix) + kEcPointSize,
+                  kEcPointSize));
+
+  // Test the result of a corner case: leading 0s in the x, y coordinates are
+  // not trimmed, but the point is fixed-length encoded.
+  spki.set(reinterpret_cast<const char*>(kSpkiEcWithZeroXY),
+           sizeof(kSpkiEcWithZeroXY));
+  EXPECT_TRUE(JwkSerializer::ConvertSpkiFromDerToJwk(spki, &public_key_jwk));
+
+  EXPECT_TRUE(public_key_jwk.GetString("alg", &string_value));
+  EXPECT_STREQ("EC", string_value.c_str());
+  EXPECT_TRUE(public_key_jwk.GetString("crv", &string_value));
+  EXPECT_STREQ("P-256", string_value.c_str());
+
+  EXPECT_TRUE(public_key_jwk.GetString("x", &string_value));
+  EXPECT_TRUE(base::Base64Decode(string_value, &decoded_coordinate));
+  EXPECT_EQ(kEcPointSize, decoded_coordinate.size());
+  EXPECT_EQ(0,
+            memcmp(decoded_coordinate.data(),
+                   kSpkiEcWithZeroXY + sizeof(kP256SpkiPrefix),
+                   kEcPointSize));
+
+  EXPECT_TRUE(public_key_jwk.GetString("y", &string_value));
+  EXPECT_TRUE(base::Base64Decode(string_value, &decoded_coordinate));
+  EXPECT_EQ(kEcPointSize, decoded_coordinate.size());
+  EXPECT_EQ(0,
+            memcmp(decoded_coordinate.data(),
+                   kSpkiEcWithZeroXY + sizeof(kP256SpkiPrefix) + kEcPointSize,
+                   kEcPointSize));
+}
+
+#else
+
+// For OpenSSL, JwkSerializer::ConvertSpkiFromDerToJwk() is not yet implemented
+// and should return false.  This unit test ensures that a stub implementation
+// is present.
+TEST(JwkSerializerOpenSSLTest, ConvertSpkiFromDerToJwkNotImplemented) {
+  base::StringPiece spki;
+  base::DictionaryValue public_key_jwk;
+
+  // The empty SPKI is trivially non-convertible...
+  EXPECT_FALSE(JwkSerializer::ConvertSpkiFromDerToJwk(spki, &public_key_jwk));
+  EXPECT_TRUE(public_key_jwk.empty());
+  // but even a valid SPKI is non-convertible via the stub OpenSSL
+  // implementation.
+  spki.set(reinterpret_cast<const char*>(kSpkiEc), sizeof(kSpkiEc));
+  EXPECT_FALSE(JwkSerializer::ConvertSpkiFromDerToJwk(spki, &public_key_jwk));
+  EXPECT_TRUE(public_key_jwk.empty());
+}
+
+#endif  // !defined(USE_OPENSSL)
+
+}  // namespace net