// SPDX-License-Identifier: Unlicense /* * sha256.c --- The sha256 algorithm * * (copied from LibTomCrypt with adaption.) */ #include "sha256.h" #include /* This is based on SHA256 implementation in LibTomCrypt that was released into * public domain by Tom St Denis. */ /* the K array */ static const unsigned long K[64] = { 0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL, 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL, 0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, 0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL, 0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL, 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL, 0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL, 0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL, 0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL, 0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL, 0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL, 0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL, 0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL }; /* Various logical functions */ #define RORc(x, y) \ ( ((((unsigned long) (x) & 0xFFFFFFFFUL) >> (unsigned long) ((y) & 31)) | \ ((unsigned long) (x) << (unsigned long) (32 - ((y) & 31)))) & 0xFFFFFFFFUL) #define Ch(x,y,z) (z ^ (x & (y ^ z))) #define Maj(x,y,z) (((x | y) & z) | (x & y)) #define S(x, n) RORc((x), (n)) #define R(x, n) (((x)&0xFFFFFFFFUL)>>(n)) #define Sigma0(x) (S(x, 2) ^ S(x, 13) ^ S(x, 22)) #define Sigma1(x) (S(x, 6) ^ S(x, 11) ^ S(x, 25)) #define Gamma0(x) (S(x, 7) ^ S(x, 18) ^ R(x, 3)) #define Gamma1(x) (S(x, 17) ^ S(x, 19) ^ R(x, 10)) #ifndef MIN #define MIN(x, y) (((x) < (y)) ? (x) : (y)) #endif #define STORE64H(x, y) \ do { \ (y)[0] = (unsigned char)(((x)>>56)&255);\ (y)[1] = (unsigned char)(((x)>>48)&255);\ (y)[2] = (unsigned char)(((x)>>40)&255);\ (y)[3] = (unsigned char)(((x)>>32)&255);\ (y)[4] = (unsigned char)(((x)>>24)&255);\ (y)[5] = (unsigned char)(((x)>>16)&255);\ (y)[6] = (unsigned char)(((x)>>8)&255);\ (y)[7] = (unsigned char)((x)&255); } while(0) #define STORE32H(x, y) \ do { (y)[0] = (unsigned char)(((x)>>24)&255); (y)[1] = (unsigned char)(((x)>>16)&255); \ (y)[2] = (unsigned char)(((x)>>8)&255); (y)[3] = (unsigned char)((x)&255); } while(0) #define LOAD32H(x, y) \ do { x = ((u32)((y)[0] & 255)<<24) | \ ((u32)((y)[1] & 255)<<16) | \ ((u32)((y)[2] & 255)<<8) | \ ((u32)((y)[3] & 255)); } while(0) /* compress 512-bits */ static int sha256_compress(struct sha256_state *md, unsigned char *buf) { u32 S[8], W[64], t0, t1; u32 t; int i; /* copy state into S */ for (i = 0; i < 8; i++) { S[i] = md->state[i]; } /* copy the state into 512-bits into W[0..15] */ for (i = 0; i < 16; i++) LOAD32H(W[i], buf + (4 * i)); /* fill W[16..63] */ for (i = 16; i < 64; i++) { W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16]; } /* Compress */ #define RND(a,b,c,d,e,f,g,h,i) \ t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i]; \ t1 = Sigma0(a) + Maj(a, b, c); \ d += t0; \ h = t0 + t1; for (i = 0; i < 64; ++i) { RND(S[0], S[1], S[2], S[3], S[4], S[5], S[6], S[7], i); t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4]; S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t; } /* feedback */ for (i = 0; i < 8; i++) { md->state[i] = md->state[i] + S[i]; } return 0; } /* Initialize the hash state */ void erofs_sha256_init(struct sha256_state *md) { md->curlen = 0; md->length = 0; md->state[0] = 0x6A09E667UL; md->state[1] = 0xBB67AE85UL; md->state[2] = 0x3C6EF372UL; md->state[3] = 0xA54FF53AUL; md->state[4] = 0x510E527FUL; md->state[5] = 0x9B05688CUL; md->state[6] = 0x1F83D9ABUL; md->state[7] = 0x5BE0CD19UL; } /** Process a block of memory though the hash @param md The hash state @param in The data to hash @param inlen The length of the data (octets) @return CRYPT_OK if successful */ int erofs_sha256_process(struct sha256_state *md, const unsigned char *in, unsigned long inlen) { unsigned long n; #define block_size 64 if (md->curlen > sizeof(md->buf)) return -1; while (inlen > 0) { if (md->curlen == 0 && inlen >= block_size) { if (sha256_compress(md, (unsigned char *) in) < 0) return -1; md->length += block_size * 8; in += block_size; inlen -= block_size; } else { n = MIN(inlen, (block_size - md->curlen)); memcpy(md->buf + md->curlen, in, n); md->curlen += n; in += n; inlen -= n; if (md->curlen == block_size) { if (sha256_compress(md, md->buf) < 0) return -1; md->length += 8 * block_size; md->curlen = 0; } } } return 0; } /** Terminate the hash to get the digest @param md The hash state @param out [out] The destination of the hash (32 bytes) @return CRYPT_OK if successful */ int erofs_sha256_done(struct sha256_state *md, unsigned char *out) { int i; if (md->curlen >= sizeof(md->buf)) return -1; /* increase the length of the message */ md->length += md->curlen * 8; /* append the '1' bit */ md->buf[md->curlen++] = (unsigned char) 0x80; /* if the length is currently above 56 bytes we append zeros * then compress. Then we can fall back to padding zeros and length * encoding like normal. */ if (md->curlen > 56) { while (md->curlen < 64) { md->buf[md->curlen++] = (unsigned char) 0; } sha256_compress(md, md->buf); md->curlen = 0; } /* pad upto 56 bytes of zeroes */ while (md->curlen < 56) { md->buf[md->curlen++] = (unsigned char) 0; } /* store length */ STORE64H(md->length, md->buf+56); sha256_compress(md, md->buf); /* copy output */ for (i = 0; i < 8; i++) STORE32H(md->state[i], out + (4 * i)); return 0; } void erofs_sha256(const unsigned char *in, unsigned long in_size, unsigned char out[32]) { struct sha256_state md; erofs_sha256_init(&md); erofs_sha256_process(&md, in, in_size); erofs_sha256_done(&md, out); } #ifdef UNITTEST #include static const struct { char *msg; unsigned char hash[32]; } tests[] = { { "", { 0xe3, 0xb0, 0xc4, 0x42, 0x98, 0xfc, 0x1c, 0x14, 0x9a, 0xfb, 0xf4, 0xc8, 0x99, 0x6f, 0xb9, 0x24, 0x27, 0xae, 0x41, 0xe4, 0x64, 0x9b, 0x93, 0x4c, 0xa4, 0x95, 0x99, 0x1b, 0x78, 0x52, 0xb8, 0x55 } }, { "abc", { 0xba, 0x78, 0x16, 0xbf, 0x8f, 0x01, 0xcf, 0xea, 0x41, 0x41, 0x40, 0xde, 0x5d, 0xae, 0x22, 0x23, 0xb0, 0x03, 0x61, 0xa3, 0x96, 0x17, 0x7a, 0x9c, 0xb4, 0x10, 0xff, 0x61, 0xf2, 0x00, 0x15, 0xad } }, { "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", { 0x24, 0x8d, 0x6a, 0x61, 0xd2, 0x06, 0x38, 0xb8, 0xe5, 0xc0, 0x26, 0x93, 0x0c, 0x3e, 0x60, 0x39, 0xa3, 0x3c, 0xe4, 0x59, 0x64, 0xff, 0x21, 0x67, 0xf6, 0xec, 0xed, 0xd4, 0x19, 0xdb, 0x06, 0xc1 } }, }; int main(int argc, char **argv) { int i; int errors = 0; unsigned char tmp[32]; for (i = 0; i < (int)(sizeof(tests) / sizeof(tests[0])); i++) { unsigned char *msg = (unsigned char *) tests[i].msg; int len = strlen(tests[i].msg); erofs_sha256(msg, len, tmp); printf("SHA256 test message %d: ", i); if (memcmp(tmp, tests[i].hash, 32) != 0) { printf("FAILED\n"); errors++; } else printf("OK\n"); } return errors; } #endif /* UNITTEST */