CrossPlatformKATTest.kt

1package com.peachpasswords23import com.peachpasswords.sync.SASDerivation4import com.peachpasswords.sync.computeVaultId5import com.peachpasswords.sync.noiseNKHkdf2ForTest6import com.peachpasswords.sync.noiseNKInitHashForTest7import com.peachpasswords.vault.VaultCrypto8import org.junit.Assert.assertArrayEquals9import org.junit.Assert.assertEquals10import org.junit.Assert.assertFalse11import org.junit.Assert.assertNotEquals12import org.junit.Test13import java.text.Normalizer1415/**16 * MN-4: cross-platform known-answer tests. These pin the byte-level output of the17 * primitives Android shares with the browser, so a regression on either side18 * (encoding, params, algorithm) is caught immediately. The Android implementations19 * are exact ports of the browser source, so these golden vectors hold on both.20 *21 * Inputs are fixed and printable; expected outputs are frozen below.22 */23class CrossPlatformKATTest {2425    private fun hex(b: ByteArray) = b.joinToString("") { "%02x".format(it) }2627    // Argon2id over the non-BMP password "test🔑" (U+1F511, UTF-8) and a fixed salt.28    private val argonSalt = ByteArray(VaultCrypto.SALT_SIZE) { it.toByte() }2930    @Test fun argon2id_non_bmp_password_vector() {31        // password "test🔑" (UTF-8) + salt bytes 0x00..0x0f, Argon2id m=64MiB t=3 p=4.32        // Generated from peach-browser argon2.ts deriveKey after the LV-1 NFC fix —33        // the emoji is NFC-stable, so this vector holds across the normalization fix.34        val key = VaultCrypto.deriveKey("test🔑", argonSalt)35        assertEquals("a519dd4e695d25c6cd69a2f89d51ddcabd952c979f5714ab29fb77f6d1ad3728", hex(key))36    }3738    @Test fun nfc_normalization_makes_composed_and_decomposed_match() {39        // MF-4 / LV-1: "café" decomposed (e + U+0301) and composed (U+00E9) must40        // derive the same key, matching the browser's password.normalize("NFC").41        val nfd = Normalizer.normalize("café", Normalizer.Form.NFD)42        val nfc = Normalizer.normalize("café", Normalizer.Form.NFC)43        assertNotEquals(nfd, nfc)44        assertArrayEquals(VaultCrypto.deriveKey(nfd, argonSalt), VaultCrypto.deriveKey(nfc, argonSalt))45    }4647    @Test fun deriveKeyRaw_does_not_normalize() {48        val nfd = Normalizer.normalize("café", Normalizer.Form.NFD)49        val nfc = Normalizer.normalize("café", Normalizer.Form.NFC)50        assertFalse(51            VaultCrypto.deriveKeyRaw(nfd, argonSalt).contentEquals(VaultCrypto.deriveKeyRaw(nfc, argonSalt)),52        )53    }5455    @Test fun compute_vault_id_vector() {56        // Blake3-256( masterKey(0x00..0x1f) || "peach-vault-id" ), hex.57        val masterKey = ByteArray(32) { it.toByte() }58        assertEquals("ae0ec54041c9ba3e20c0c2d33bdeb2552f3b9a3fb4be3286ec0ef0a61be2fc9c", computeVaultId(masterKey))59    }6061    @Test fun sas_derivation_vector() {62        // First 8 bytes are unsigned big-endian, modulo 100_000_000.63        val handshakeHash = byteArrayOf(0x12, 0x34, 0x56, 0x78) + ByteArray(28)64        assertEquals("67721216", SASDerivation.derive(handshakeHash))65    }6667    // PCH-01-002: the Noise protocol-name init hash and the MixKey/Split HKDF now68    // derive over BLAKE2s to match the declared pattern name. These vectors are69    // pinned IDENTICALLY in peach-browser's noise-blake2s-kat.test.ts — a mismatch70    // here means the two repos' Noise wire derivations have diverged (which would71    // break cross-device pairing/sync). A SHA-256 revert on either side also fails.72    @Test fun noise_nk_init_hash_is_blake2s_vector() {73        assertEquals(74            "e01688d376ef280a27a8af5c559024a02017585b3763763e4f3c7118a979b09e",75            hex(noiseNKInitHashForTest()),76        )77    }7879    @Test fun noise_hkdf2_blake2s_vector() {80        // ck = 0x00..0x1f, ikm = 0x20..0x3f.81        val ck = ByteArray(32) { it.toByte() }82        val ikm = ByteArray(32) { (it + 32).toByte() }83        val (nk1, nk2) = noiseNKHkdf2ForTest(ck, ikm)84        assertEquals("6a96444e20e8d4c1cee974416acae1c10b3c92886010e54ed94dafb2c3b80ea0", hex(nk1))85        assertEquals("57af120b0de7acbe7907ec149c5ae870a2dbb74232b65777ba4123f1f7f888f5", hex(nk2))86    }87}