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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2022-2024 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.4 */5 6#include <linux/compiler.h>7#include <tools/le_byteshift.h>8#include <sys/random.h>9#include <sys/auxv.h>10#include <string.h>11#include <stdint.h>12#include <stdbool.h>13#include "../kselftest.h"14 15#if defined(__aarch64__)16static bool cpu_has_capabilities(void)17{18 return getauxval(AT_HWCAP) & HWCAP_ASIMD;19}20#elif defined(__s390x__)21static bool cpu_has_capabilities(void)22{23 return getauxval(AT_HWCAP) & HWCAP_S390_VXRS;24}25#else26static bool cpu_has_capabilities(void)27{28 return true;29}30#endif31 32static uint32_t rol32(uint32_t word, unsigned int shift)33{34 return (word << (shift & 31)) | (word >> ((-shift) & 31));35}36 37static void reference_chacha20_blocks(uint8_t *dst_bytes, const uint32_t *key, uint32_t *counter, size_t nblocks)38{39 uint32_t s[16] = {40 0x61707865U, 0x3320646eU, 0x79622d32U, 0x6b206574U,41 key[0], key[1], key[2], key[3], key[4], key[5], key[6], key[7],42 counter[0], counter[1], 0, 043 };44 45 while (nblocks--) {46 uint32_t x[16];47 memcpy(x, s, sizeof(x));48 for (unsigned int r = 0; r < 20; r += 2) {49 #define QR(a, b, c, d) ( \50 x[a] += x[b], \51 x[d] = rol32(x[d] ^ x[a], 16), \52 x[c] += x[d], \53 x[b] = rol32(x[b] ^ x[c], 12), \54 x[a] += x[b], \55 x[d] = rol32(x[d] ^ x[a], 8), \56 x[c] += x[d], \57 x[b] = rol32(x[b] ^ x[c], 7))58 59 QR(0, 4, 8, 12);60 QR(1, 5, 9, 13);61 QR(2, 6, 10, 14);62 QR(3, 7, 11, 15);63 QR(0, 5, 10, 15);64 QR(1, 6, 11, 12);65 QR(2, 7, 8, 13);66 QR(3, 4, 9, 14);67 }68 for (unsigned int i = 0; i < 16; ++i, dst_bytes += sizeof(uint32_t))69 put_unaligned_le32(x[i] + s[i], dst_bytes);70 if (!++s[12])71 ++s[13];72 }73 counter[0] = s[12];74 counter[1] = s[13];75}76 77void __weak __arch_chacha20_blocks_nostack(uint8_t *dst_bytes, const uint32_t *key, uint32_t *counter, size_t nblocks)78{79 ksft_exit_skip("Not implemented on architecture\n");80}81 82int main(int argc, char *argv[])83{84 enum { TRIALS = 1000, BLOCKS = 128, BLOCK_SIZE = 64 };85 uint32_t key[8], counter1[2], counter2[2];86 uint8_t output1[BLOCK_SIZE * BLOCKS], output2[BLOCK_SIZE * BLOCKS];87 88 ksft_print_header();89 if (!cpu_has_capabilities())90 ksft_exit_skip("Required CPU capabilities missing\n");91 ksft_set_plan(1);92 93 for (unsigned int trial = 0; trial < TRIALS; ++trial) {94 if (getrandom(key, sizeof(key), 0) != sizeof(key))95 ksft_exit_skip("getrandom() failed unexpectedly\n");96 memset(counter1, 0, sizeof(counter1));97 reference_chacha20_blocks(output1, key, counter1, BLOCKS);98 for (unsigned int split = 0; split < BLOCKS; ++split) {99 memset(output2, 'X', sizeof(output2));100 memset(counter2, 0, sizeof(counter2));101 if (split)102 __arch_chacha20_blocks_nostack(output2, key, counter2, split);103 __arch_chacha20_blocks_nostack(output2 + split * BLOCK_SIZE, key, counter2, BLOCKS - split);104 if (memcmp(output1, output2, sizeof(output1)))105 ksft_exit_fail_msg("Main loop outputs do not match on trial %u, split %u\n", trial, split);106 if (memcmp(counter1, counter2, sizeof(counter1)))107 ksft_exit_fail_msg("Main loop counters do not match on trial %u, split %u\n", trial, split);108 }109 }110 memset(counter1, 0, sizeof(counter1));111 counter1[0] = (uint32_t)-BLOCKS + 2;112 memset(counter2, 0, sizeof(counter2));113 counter2[0] = (uint32_t)-BLOCKS + 2;114 115 reference_chacha20_blocks(output1, key, counter1, BLOCKS);116 __arch_chacha20_blocks_nostack(output2, key, counter2, BLOCKS);117 if (memcmp(output1, output2, sizeof(output1)))118 ksft_exit_fail_msg("Block limit outputs do not match after first round\n");119 if (memcmp(counter1, counter2, sizeof(counter1)))120 ksft_exit_fail_msg("Block limit counters do not match after first round\n");121 122 reference_chacha20_blocks(output1, key, counter1, BLOCKS);123 __arch_chacha20_blocks_nostack(output2, key, counter2, BLOCKS);124 if (memcmp(output1, output2, sizeof(output1)))125 ksft_exit_fail_msg("Block limit outputs do not match after second round\n");126 if (memcmp(counter1, counter2, sizeof(counter1)))127 ksft_exit_fail_msg("Block limit counters do not match after second round\n");128 129 ksft_test_result_pass("chacha: PASS\n");130 ksft_exit_pass();131 return 0;132}133