diff options
Diffstat (limited to 'security-utils/src/test/java/com')
-rw-r--r-- | security-utils/src/test/java/com/yahoo/security/HKDFTest.java | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/security-utils/src/test/java/com/yahoo/security/HKDFTest.java b/security-utils/src/test/java/com/yahoo/security/HKDFTest.java new file mode 100644 index 00000000000..c2d8b99e9a7 --- /dev/null +++ b/security-utils/src/test/java/com/yahoo/security/HKDFTest.java @@ -0,0 +1,214 @@ +// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root. +package com.yahoo.security; + +import org.bouncycastle.util.encoders.Hex; +import org.junit.jupiter.api.Test; + +import static org.junit.jupiter.api.Assertions.assertEquals; +import static org.junit.jupiter.api.Assertions.assertThrows; + +/** + * HKDF tests that ensure that the output of our own implementation matches the test + * vectors given in <a href="https://tools.ietf.org/html/rfc5869">RFC-5869</a>. + * + * We don't expose the internal PRK (pseudo-random key) value of the HKDF itself, + * so we don't test it explicitly. The actual OKM (output keying material) inherently + * depends on it, so its correctness is verified transitively. + * + * @author vekterli + */ +public class HKDFTest { + + private static byte[] fromHex(String hex) { + return Hex.decode(hex); + } + + private static String toHex(byte[] bytes) { + return Hex.toHexString(bytes); + } + + /* + A.1. Test Case 1 + + Basic test case with SHA-256 + + Hash = SHA-256 + IKM = 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b (22 octets) + salt = 0x000102030405060708090a0b0c (13 octets) + info = 0xf0f1f2f3f4f5f6f7f8f9 (10 octets) + L = 42 + + PRK = 0x077709362c2e32df0ddc3f0dc47bba63 + 90b6c73bb50f9c3122ec844ad7c2b3e5 (32 octets) + OKM = 0x3cb25f25faacd57a90434f64d0362f2a + 2d2d0a90cf1a5a4c5db02d56ecc4c5bf + 34007208d5b887185865 (42 octets) + */ + @Test + void rfc_5869_test_vector_case_1() { + var ikm = fromHex("0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b"); + var salt = fromHex("000102030405060708090a0b0c"); + var info = fromHex("f0f1f2f3f4f5f6f7f8f9"); + + var hkdf = HKDF.extractedFrom(salt, ikm); + var okm = hkdf.expand(42, info); + assertEquals(toHex(okm), + "3cb25f25faacd57a90434f64d0362f2a" + + "2d2d0a90cf1a5a4c5db02d56ecc4c5bf" + + "34007208d5b887185865"); + } + + @Test + void rfc_5869_test_vector_case_1_block_boundary_edge_cases() { + var ikm = fromHex("0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b"); + var salt = fromHex("000102030405060708090a0b0c"); + var info = fromHex("f0f1f2f3f4f5f6f7f8f9"); + + var hkdf = HKDF.extractedFrom(salt, ikm); + var okm = hkdf.expand(31, info); // One less than block size + assertEquals(toHex(okm), + "3cb25f25faacd57a90434f64d0362f2a" + + "2d2d0a90cf1a5a4c5db02d56ecc4c5"); + + okm = hkdf.expand(32, info); // Exactly equal to block size + assertEquals(toHex(okm), + "3cb25f25faacd57a90434f64d0362f2a" + + "2d2d0a90cf1a5a4c5db02d56ecc4c5bf"); + + okm = hkdf.expand(33, info); // One more than block size + assertEquals(toHex(okm), + "3cb25f25faacd57a90434f64d0362f2a" + + "2d2d0a90cf1a5a4c5db02d56ecc4c5bf" + + "34"); + } + + /* + A.2. Test Case 2 + + Test with SHA-256 and longer inputs/outputs + + Hash = SHA-256 + IKM = 0x000102030405060708090a0b0c0d0e0f + 101112131415161718191a1b1c1d1e1f + 202122232425262728292a2b2c2d2e2f + 303132333435363738393a3b3c3d3e3f + 404142434445464748494a4b4c4d4e4f (80 octets) + salt = 0x606162636465666768696a6b6c6d6e6f + 707172737475767778797a7b7c7d7e7f + 808182838485868788898a8b8c8d8e8f + 909192939495969798999a9b9c9d9e9f + a0a1a2a3a4a5a6a7a8a9aaabacadaeaf (80 octets) + info = 0xb0b1b2b3b4b5b6b7b8b9babbbcbdbebf + c0c1c2c3c4c5c6c7c8c9cacbcccdcecf + d0d1d2d3d4d5d6d7d8d9dadbdcdddedf + e0e1e2e3e4e5e6e7e8e9eaebecedeeef + f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff (80 octets) + L = 82 + + PRK = 0x06a6b88c5853361a06104c9ceb35b45c + ef760014904671014a193f40c15fc244 (32 octets) + OKM = 0xb11e398dc80327a1c8e7f78c596a4934 + 4f012eda2d4efad8a050cc4c19afa97c + 59045a99cac7827271cb41c65e590e09 + da3275600c2f09b8367793a9aca3db71 + cc30c58179ec3e87c14c01d5c1f3434f + 1d87 (82 octets) + */ + @Test + void rfc_5869_test_vector_case_2() { + var ikm = fromHex("000102030405060708090a0b0c0d0e0f" + + "101112131415161718191a1b1c1d1e1f" + + "202122232425262728292a2b2c2d2e2f" + + "303132333435363738393a3b3c3d3e3f" + + "404142434445464748494a4b4c4d4e4f"); + var salt = fromHex("606162636465666768696a6b6c6d6e6f" + + "707172737475767778797a7b7c7d7e7f" + + "808182838485868788898a8b8c8d8e8f" + + "909192939495969798999a9b9c9d9e9f" + + "a0a1a2a3a4a5a6a7a8a9aaabacadaeaf"); + var info = fromHex("b0b1b2b3b4b5b6b7b8b9babbbcbdbebf" + + "c0c1c2c3c4c5c6c7c8c9cacbcccdcecf" + + "d0d1d2d3d4d5d6d7d8d9dadbdcdddedf" + + "e0e1e2e3e4e5e6e7e8e9eaebecedeeef" + + "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff"); + + var hkdf = HKDF.extractedFrom(salt, ikm); + var okm = hkdf.expand(82, info); + assertEquals(toHex(okm), + "b11e398dc80327a1c8e7f78c596a4934" + + "4f012eda2d4efad8a050cc4c19afa97c" + + "59045a99cac7827271cb41c65e590e09" + + "da3275600c2f09b8367793a9aca3db71" + + "cc30c58179ec3e87c14c01d5c1f3434f" + + "1d87"); + } + + /* + A.3. Test Case 3 + + Test with SHA-256 and zero-length salt/info + + Hash = SHA-256 + IKM = 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b (22 octets) + salt = (0 octets) + info = (0 octets) + L = 42 + + PRK = 0x19ef24a32c717b167f33a91d6f648bdf + 96596776afdb6377ac434c1c293ccb04 (32 octets) + OKM = 0x8da4e775a563c18f715f802a063c5a31 + b8a11f5c5ee1879ec3454e5f3c738d2d + 9d201395faa4b61a96c8 (42 octets) + */ + @Test + void rfc_5869_test_vector_case_3() { + var ikm = fromHex("0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b"); + var info = new byte[0]; + + // We don't allow empty salt to the salted factory function, so this is equivalent. + var hkdf = HKDF.unsaltedExtractedFrom(ikm); + var okm = hkdf.expand(42, info); + var expectedKey = "8da4e775a563c18f715f802a063c5a31" + + "b8a11f5c5ee1879ec3454e5f3c738d2d" + + "9d201395faa4b61a96c8"; + assertEquals(toHex(okm), expectedKey); + + // expand() without explicit context should return as if an empty context array was passed + okm = hkdf.expand(42); + assertEquals(toHex(okm), expectedKey); + } + + @Test + void requested_key_size_is_bounded_and_checked() { + var ikm = fromHex("0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b"); + var salt = fromHex("000102030405060708090a0b0c"); + var hkdf = HKDF.extractedFrom(salt, ikm); + + assertThrows(IllegalArgumentException.class, () -> hkdf.expand(-1)); // Can't request negative output size + + assertThrows(IllegalArgumentException.class, () -> hkdf.expand(0)); // Need at least 1 key byte + + assertThrows(IllegalArgumentException.class, () -> hkdf.expand(HKDF.MAX_OUTPUT_SIZE + 1)); // 1 too large + + // However, exactly max should work (though a strange size to request in practice) + var okm = hkdf.expand(HKDF.MAX_OUTPUT_SIZE); + assertEquals(okm.length, HKDF.MAX_OUTPUT_SIZE); + } + + @Test + void missing_salt_to_salted_factory_function_throws_exception() { + var ikm = fromHex("0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b"); + assertThrows(NullPointerException.class, () -> HKDF.extractedFrom(null, ikm)); + assertThrows(IllegalArgumentException.class, () -> HKDF.extractedFrom(new byte[0], ikm)); + } + + @Test + void ikm_can_not_be_null_or_empty() { + var salt = fromHex("000102030405060708090a0b0c"); + assertThrows(NullPointerException.class, () -> HKDF.extractedFrom(salt, null)); + assertThrows(IllegalArgumentException.class, () -> HKDF.extractedFrom(salt, new byte[0])); + assertThrows(NullPointerException.class, () -> HKDF.unsaltedExtractedFrom(null)); + assertThrows(IllegalArgumentException.class, () -> HKDF.unsaltedExtractedFrom(new byte[0])); + } + +} |