| // Copyright 2020 Google LLC |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| // |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| package subtle |
| |
| import ( |
| "encoding/hex" |
| "fmt" |
| "strings" |
| "testing" |
| |
| "github.com/google/tink/go/subtle/random" |
| ) |
| |
| // Tests the implementation against the test vectors from RFC 5869. |
| var hkdfTests = []struct { |
| hashAlg string |
| key string |
| salt string |
| info string |
| tagSize uint32 |
| expectedKDF string |
| }{ |
| { |
| hashAlg: "SHA256", |
| key: "0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b", |
| salt: "000102030405060708090a0b0c", |
| info: "f0f1f2f3f4f5f6f7f8f9", |
| tagSize: 42, |
| expectedKDF: "3cb25f25faacd57a90434f64d0362f2a2d2d0a90cf1a5a4c5db02d56ecc4c5bf34007208d5b887185865", |
| }, |
| { |
| hashAlg: "SHA256", |
| key: "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f" + |
| "202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f" + |
| "404142434445464748494a4b4c4d4e4f", |
| salt: "606162636465666768696a6b6c6d6e6f707172737475767778797a7b7c7d7e7f" + |
| "808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f" + |
| "a0a1a2a3a4a5a6a7a8a9aaabacadaeaf", |
| info: "b0b1b2b3b4b5b6b7b8b9babbbcbdbebfc0c1c2c3c4c5c6c7c8c9cacbcccdcecf" + |
| "d0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeef" + |
| "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff", |
| tagSize: 82, |
| expectedKDF: "b11e398dc80327a1c8e7f78c596a49344f012eda2d4efad8a050cc4c19afa97c" + |
| "59045a99cac7827271cb41c65e590e09da3275600c2f09b8367793a9aca3db71" + |
| "cc30c58179ec3e87c14c01d5c1f3434f1d87", |
| }, |
| { |
| hashAlg: "SHA256", |
| key: "0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b", |
| salt: "", |
| info: "", |
| tagSize: 42, |
| expectedKDF: "8da4e775a563c18f715f802a063c5a31b8a11f5c5ee1879ec3454e5f3c738d2d" + |
| "9d201395faa4b61a96c8", |
| }, |
| { |
| hashAlg: "SHA1", |
| key: "0b0b0b0b0b0b0b0b0b0b0b", |
| salt: "000102030405060708090a0b0c", |
| info: "f0f1f2f3f4f5f6f7f8f9", |
| tagSize: 42, |
| expectedKDF: "085a01ea1b10f36933068b56efa5ad81a4f14b822f5b091568a9cdd4f155fda2c22e422478d305f3f896", |
| }, |
| { |
| hashAlg: "SHA1", |
| key: "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f" + |
| "202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f" + |
| "404142434445464748494a4b4c4d4e4f", |
| salt: "606162636465666768696a6b6c6d6e6f707172737475767778797a7b7c7d7e7f" + |
| "808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f" + |
| "a0a1a2a3a4a5a6a7a8a9aaabacadaeaf", |
| info: "b0b1b2b3b4b5b6b7b8b9babbbcbdbebfc0c1c2c3c4c5c6c7c8c9cacbcccdcecf" + |
| "d0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeef" + |
| "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff", |
| tagSize: 82, |
| expectedKDF: "0bd770a74d1160f7c9f12cd5912a06ebff6adcae899d92191fe4305673ba2ffe" + |
| "8fa3f1a4e5ad79f3f334b3b202b2173c486ea37ce3d397ed034c7f9dfeb15c5e" + |
| "927336d0441f4c4300e2cff0d0900b52d3b4", |
| }, |
| { |
| hashAlg: "SHA1", |
| key: "0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b", |
| salt: "", |
| info: "", |
| tagSize: 42, |
| expectedKDF: "0ac1af7002b3d761d1e55298da9d0506b9ae52057220a306e07b6b87e8df21d0" + |
| "ea00033de03984d34918", |
| }, |
| { |
| hashAlg: "SHA1", |
| key: "0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c", |
| salt: "", |
| info: "", |
| tagSize: 42, |
| expectedKDF: "2c91117204d745f3500d636a62f64f0ab3bae548aa53d423b0d1f27ebba6f5e5" + |
| "673a081d70cce7acfc48", |
| }, |
| } |
| |
| func TestHKDFBasic(t *testing.T) { |
| for ti, test := range hkdfTests { |
| k, _ := hex.DecodeString(test.key) |
| s, _ := hex.DecodeString(test.salt) |
| i, _ := hex.DecodeString(test.info) |
| |
| result, err := ComputeHKDF(test.hashAlg, k, s, i, test.tagSize) |
| r := hex.EncodeToString(result) |
| fmt.Printf("Test no: %d\n", ti) |
| fmt.Printf("Length of tag :%d\n", test.tagSize) |
| fmt.Printf("Length of result :%d\n", len(r)) |
| fmt.Printf("Length of expected :%d\n\n\n", len(test.expectedKDF)) |
| if err != nil { |
| t.Errorf("mac computation failed in test case %d: %s", ti, err) |
| } |
| if r != test.expectedKDF { |
| t.Errorf("incorrect hkdf in test case %d: expect %s, got %s", |
| ti, test.expectedKDF, r) |
| } |
| } |
| } |
| |
| func TestNewHMACWithInvalidInput(t *testing.T) { |
| // invalid hash algorithm |
| _, err := ComputeHKDF("SHA0", random.GetRandomBytes(16), nil, nil, 32) |
| if err == nil || !strings.Contains(err.Error(), "invalid hash algorithm") { |
| t.Errorf("expect an error when hash algorithm is invalid") |
| } |
| // tag too short |
| _, err = ComputeHKDF("SHA256", random.GetRandomBytes(16), nil, nil, 9) |
| if err == nil || !strings.Contains(err.Error(), "tag size too small") { |
| t.Errorf("expect an error when tag size is too small") |
| } |
| // tag too big |
| _, err = ComputeHKDF("SHA1", random.GetRandomBytes(16), nil, nil, 5101) |
| if err == nil || !strings.Contains(err.Error(), "tag size too big") { |
| t.Errorf("expect an error when tag size is too big") |
| } |
| _, err = ComputeHKDF("SHA256", random.GetRandomBytes(16), nil, nil, 8162) |
| if err == nil || !strings.Contains(err.Error(), "tag size too big") { |
| t.Errorf("expect an error when tag size is too big") |
| } |
| _, err = ComputeHKDF("SHA512", random.GetRandomBytes(16), nil, nil, 16323) |
| if err == nil || !strings.Contains(err.Error(), "tag size too big") { |
| t.Errorf("expect an error when tag size is too big") |
| } |
| } |