1 // Copyright 2017 Google Inc.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 //
15 ////////////////////////////////////////////////////////////////////////////////
16
17 #include "tink/subtle/hkdf.h"
18
19 #include <string>
20 #include <vector>
21
22 #include "gtest/gtest.h"
23 #include "absl/strings/escaping.h"
24 #include "tink/subtle/common_enums.h"
25 #include "tink/util/secret_data.h"
26 #include "tink/util/status.h"
27 #include "tink/util/statusor.h"
28
29 namespace crypto {
30 namespace tink {
31 namespace subtle {
32 namespace {
33
34 class HkdfTest : public ::testing::Test {};
35
36 struct TestVector {
37 HashType hash_type;
38 std::string ikm_hex;
39 std::string salt_hex;
40 std::string info_hex;
41 size_t out_len;
42 std::string out_key_hex;
43 };
44
45 // Tests vectors from RFC 5869.
46 static const std::vector<TestVector> test_vector(
47 {{
48 HashType::SHA256, "0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b",
49 "000102030405060708090a0b0c", "f0f1f2f3f4f5f6f7f8f9", 42,
50 "3cb25f25faacd57a90434f64d0362f2a2d2d0a90cf1a5a4c5db02d56ecc4c5bf34007"
51 "208"
52 "d5b887185865",
53 },
54 {
55 HashType::SHA256,
56 "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"
57 "202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f"
58 "404142434445464748494a4b4c4d4e4f",
59 "606162636465666768696a6b6c6d6e6f707172737475767778797a7b7c7d7e7f"
60 "808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f"
61 "a0a1a2a3a4a5a6a7a8a9aaabacadaeaf",
62 "b0b1b2b3b4b5b6b7b8b9babbbcbdbebfc0c1c2c3c4c5c6c7c8c9cacbcccdcecf"
63 "d0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeef"
64 "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff",
65 82,
66 "b11e398dc80327a1c8e7f78c596a49344f012eda2d4efad8a050cc4c19afa97c"
67 "59045a99cac7827271cb41c65e590e09da3275600c2f09b8367793a9aca3db71"
68 "cc30c58179ec3e87c14c01d5c1f3434f1d87",
69 },
70 {HashType::SHA256, "0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b", "", "",
71 42,
72 "8da4e775a563c18f715f802a063c5a31b8a11f5c5ee1879ec3454e5f3c738d2d"
73 "9d201395faa4b61a96c8"},
74 {HashType::SHA1, "0b0b0b0b0b0b0b0b0b0b0b", "000102030405060708090a0b0c",
75 "f0f1f2f3f4f5f6f7f8f9", 42,
76 "085a01ea1b10f36933068b56efa5ad81a4f14b822f5b091568a9cdd4f155fda2c22e4224"
77 "78d305f3f896"},
78 {HashType::SHA1,
79 "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"
80 "202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f"
81 "404142434445464748494a4b4c4d4e4f",
82 "606162636465666768696a6b6c6d6e6f707172737475767778797a7b7c7d7e7f"
83 "808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f"
84 "a0a1a2a3a4a5a6a7a8a9aaabacadaeaf",
85 "b0b1b2b3b4b5b6b7b8b9babbbcbdbebfc0c1c2c3c4c5c6c7c8c9cacbcccdcecf"
86 "d0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeef"
87 "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff",
88 82,
89 "0bd770a74d1160f7c9f12cd5912a06ebff6adcae899d92191fe4305673ba2ffe"
90 "8fa3f1a4e5ad79f3f334b3b202b2173c486ea37ce3d397ed034c7f9dfeb15c5e"
91 "927336d0441f4c4300e2cff0d0900b52d3b4"},
92 {HashType::SHA1, "0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b", "", "",
93 42,
94 "0ac1af7002b3d761d1e55298da9d0506b9ae52057220a306e07b6b87e8df21d0"
95 "ea00033de03984d34918"}});
96
TEST_F(HkdfTest,testBasic)97 TEST_F(HkdfTest, testBasic) {
98 for (const TestVector& test : test_vector) {
99 auto hkdf_or =
100 Hkdf::ComputeHkdf(test.hash_type, absl::HexStringToBytes(test.ikm_hex),
101 absl::HexStringToBytes(test.salt_hex),
102 absl::HexStringToBytes(test.info_hex), test.out_len);
103 ASSERT_TRUE(hkdf_or.ok());
104 EXPECT_EQ(absl::BytesToHexString(hkdf_or.value()), test.out_key_hex);
105 }
106 }
107
TEST_F(HkdfTest,testBasicSecretData)108 TEST_F(HkdfTest, testBasicSecretData) {
109 for (const TestVector& test : test_vector) {
110 auto hkdf_or = Hkdf::ComputeHkdf(
111 test.hash_type,
112 util::SecretDataFromStringView(absl::HexStringToBytes(test.ikm_hex)),
113 absl::HexStringToBytes(test.salt_hex),
114 absl::HexStringToBytes(test.info_hex), test.out_len);
115 ASSERT_TRUE(hkdf_or.ok());
116 EXPECT_EQ(
117 absl::BytesToHexString(util::SecretDataAsStringView(hkdf_or.value())),
118 test.out_key_hex);
119 }
120 }
121
TEST_F(HkdfTest,testLongOutput)122 TEST_F(HkdfTest, testLongOutput) {
123 TestVector test = test_vector[0];
124 auto status_or_string =
125 Hkdf::ComputeHkdf(test.hash_type, absl::HexStringToBytes(test.ikm_hex),
126 absl::HexStringToBytes(test.salt_hex),
127 absl::HexStringToBytes(test.info_hex),
128 255 * 32 + 1 /* 255 * hashLength + 1 */);
129 EXPECT_FALSE(status_or_string.ok());
130 EXPECT_EQ(status_or_string.status().message(), "HKDF failed");
131 }
132
TEST_F(HkdfTest,ComputeEciesHkdfSecretData)133 TEST_F(HkdfTest, ComputeEciesHkdfSecretData) {
134 for (const TestVector& test : test_vector) {
135 std::string ikm = absl::HexStringToBytes(test.ikm_hex);
136 std::string kem_bytes = ikm.substr(0, ikm.size() / 2);
137 util::SecretData shared_secret(ikm.begin() + ikm.size() / 2, ikm.end());
138 auto hkdf_or = Hkdf::ComputeEciesHkdfSymmetricKey(
139 test.hash_type, kem_bytes, shared_secret,
140 absl::HexStringToBytes(test.salt_hex),
141 absl::HexStringToBytes(test.info_hex), test.out_len);
142 ASSERT_TRUE(hkdf_or.ok());
143 EXPECT_EQ(
144 absl::BytesToHexString(util::SecretDataAsStringView(hkdf_or.value())),
145 test.out_key_hex);
146 }
147 }
148
149 } // namespace
150 } // namespace subtle
151 } // namespace tink
152 } // namespace crypto
153
154