/* $OpenBSD: md4.c,v 1.6 2004/05/28 15:10:27 millert Exp $ */ /* * This code implements the MD4 message-digest algorithm. * The algorithm is due to Ron Rivest. This code was * written by Colin Plumb in 1993, no copyright is claimed. * This code is in the public domain; do with it what you wish. * Todd C. Miller modified the MD5 code to do MD4 based on RFC 1186. * * Equivalent code is available from RSA Data Security, Inc. * This code has been tested against that, and is equivalent, * except that you don't need to include two pages of legalese * with every copy. * * To compute the message digest of a chunk of bytes, declare an * MD4Context structure, pass it to MD4Init, call MD4Update as * needed on buffers full of bytes, and then call MD4Final, which * will fill a supplied 16-byte array with the digest. */ #if defined(LIBC_SCCS) && !defined(lint) static const char rcsid[] = "$OpenBSD: md4.c,v 1.6 2004/05/28 15:10:27 millert Exp $"; #endif /* LIBC_SCCS and not lint */ #include #include #include #define PUT_64BIT_LE(cp, value) do { \ (cp)[7] = (value) >> 56; \ (cp)[6] = (value) >> 48; \ (cp)[5] = (value) >> 40; \ (cp)[4] = (value) >> 32; \ (cp)[3] = (value) >> 24; \ (cp)[2] = (value) >> 16; \ (cp)[1] = (value) >> 8; \ (cp)[0] = (value); } while (0) #define PUT_32BIT_LE(cp, value) do { \ (cp)[3] = (value) >> 24; \ (cp)[2] = (value) >> 16; \ (cp)[1] = (value) >> 8; \ (cp)[0] = (value); } while (0) static u_int8_t PADDING[MD4_BLOCK_LENGTH] = { 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; /* * Start MD4 accumulation. * Set bit count to 0 and buffer to mysterious initialization constants. */ void MD4Init(MD4_CTX *ctx) { ctx->count = 0; ctx->state[0] = 0x67452301; ctx->state[1] = 0xefcdab89; ctx->state[2] = 0x98badcfe; ctx->state[3] = 0x10325476; } /* * Update context to reflect the concatenation of another buffer full * of bytes. */ void MD4Update(MD4_CTX *ctx, const unsigned char *input, size_t len) { size_t have, need; /* Check how many bytes we already have and how many more we need. */ have = (size_t)((ctx->count >> 3) & (MD4_BLOCK_LENGTH - 1)); need = MD4_BLOCK_LENGTH - have; /* Update bitcount */ ctx->count += (u_int64_t)len << 3; if (len >= need) { if (have != 0) { memcpy(ctx->buffer + have, input, need); MD4Transform(ctx->state, ctx->buffer); input += need; len -= need; have = 0; } /* Process data in MD4_BLOCK_LENGTH-byte chunks. */ while (len >= MD4_BLOCK_LENGTH) { MD4Transform(ctx->state, input); input += MD4_BLOCK_LENGTH; len -= MD4_BLOCK_LENGTH; } } /* Handle any remaining bytes of data. */ if (len != 0) memcpy(ctx->buffer + have, input, len); } /* * Pad pad to 64-byte boundary with the bit pattern * 1 0* (64-bit count of bits processed, MSB-first) */ void MD4Pad(MD4_CTX *ctx) { u_int8_t count[8]; size_t padlen; /* Convert count to 8 bytes in little endian order. */ PUT_64BIT_LE(count, ctx->count); /* Pad out to 56 mod 64. */ padlen = MD4_BLOCK_LENGTH - ((ctx->count >> 3) & (MD4_BLOCK_LENGTH - 1)); if (padlen < 1 + 8) padlen += MD4_BLOCK_LENGTH; MD4Update(ctx, PADDING, padlen - 8); /* padlen - 8 <= 64 */ MD4Update(ctx, count, 8); } /* * Final wrapup--call MD4Pad, fill in digest and zero out ctx. */ void MD4Final(unsigned char digest[MD4_DIGEST_LENGTH], MD4_CTX *ctx) { int i; MD4Pad(ctx); if (digest != NULL) { for (i = 0; i < 4; i++) PUT_32BIT_LE(digest + i * 4, ctx->state[i]); memset(ctx, 0, sizeof(*ctx)); } } /* The three core functions - F1 is optimized somewhat */ /* #define F1(x, y, z) (x & y | ~x & z) */ #define F1(x, y, z) (z ^ (x & (y ^ z))) #define F2(x, y, z) ((x & y) | (x & z) | (y & z)) #define F3(x, y, z) (x ^ y ^ z) /* This is the central step in the MD4 algorithm. */ #define MD4STEP(f, w, x, y, z, data, s) \ ( w += f(x, y, z) + data, w = w<>(32-s) ) /* * The core of the MD4 algorithm, this alters an existing MD4 hash to * reflect the addition of 16 longwords of new data. MD4Update blocks * the data and converts bytes into longwords for this routine. */ void MD4Transform(u_int32_t state[4], const u_int8_t block[MD4_BLOCK_LENGTH]) { u_int32_t a, b, c, d, in[MD4_BLOCK_LENGTH / 4]; #if BYTE_ORDER == LITTLE_ENDIAN memcpy(in, block, sizeof(in)); #else for (a = 0; a < MD4_BLOCK_LENGTH / 4; a++) { in[a] = (u_int32_t)( (u_int32_t)(block[a * 4 + 0]) | (u_int32_t)(block[a * 4 + 1]) << 8 | (u_int32_t)(block[a * 4 + 2]) << 16 | (u_int32_t)(block[a * 4 + 3]) << 24); } #endif a = state[0]; b = state[1]; c = state[2]; d = state[3]; MD4STEP(F1, a, b, c, d, in[ 0], 3); MD4STEP(F1, d, a, b, c, in[ 1], 7); MD4STEP(F1, c, d, a, b, in[ 2], 11); MD4STEP(F1, b, c, d, a, in[ 3], 19); MD4STEP(F1, a, b, c, d, in[ 4], 3); MD4STEP(F1, d, a, b, c, in[ 5], 7); MD4STEP(F1, c, d, a, b, in[ 6], 11); MD4STEP(F1, b, c, d, a, in[ 7], 19); MD4STEP(F1, a, b, c, d, in[ 8], 3); MD4STEP(F1, d, a, b, c, in[ 9], 7); MD4STEP(F1, c, d, a, b, in[10], 11); MD4STEP(F1, b, c, d, a, in[11], 19); MD4STEP(F1, a, b, c, d, in[12], 3); MD4STEP(F1, d, a, b, c, in[13], 7); MD4STEP(F1, c, d, a, b, in[14], 11); MD4STEP(F1, b, c, d, a, in[15], 19); MD4STEP(F2, a, b, c, d, in[ 0] + 0x5a827999, 3); MD4STEP(F2, d, a, b, c, in[ 4] + 0x5a827999, 5); MD4STEP(F2, c, d, a, b, in[ 8] + 0x5a827999, 9); MD4STEP(F2, b, c, d, a, in[12] + 0x5a827999, 13); MD4STEP(F2, a, b, c, d, in[ 1] + 0x5a827999, 3); MD4STEP(F2, d, a, b, c, in[ 5] + 0x5a827999, 5); MD4STEP(F2, c, d, a, b, in[ 9] + 0x5a827999, 9); MD4STEP(F2, b, c, d, a, in[13] + 0x5a827999, 13); MD4STEP(F2, a, b, c, d, in[ 2] + 0x5a827999, 3); MD4STEP(F2, d, a, b, c, in[ 6] + 0x5a827999, 5); MD4STEP(F2, c, d, a, b, in[10] + 0x5a827999, 9); MD4STEP(F2, b, c, d, a, in[14] + 0x5a827999, 13); MD4STEP(F2, a, b, c, d, in[ 3] + 0x5a827999, 3); MD4STEP(F2, d, a, b, c, in[ 7] + 0x5a827999, 5); MD4STEP(F2, c, d, a, b, in[11] + 0x5a827999, 9); MD4STEP(F2, b, c, d, a, in[15] + 0x5a827999, 13); MD4STEP(F3, a, b, c, d, in[ 0] + 0x6ed9eba1, 3); MD4STEP(F3, d, a, b, c, in[ 8] + 0x6ed9eba1, 9); MD4STEP(F3, c, d, a, b, in[ 4] + 0x6ed9eba1, 11); MD4STEP(F3, b, c, d, a, in[12] + 0x6ed9eba1, 15); MD4STEP(F3, a, b, c, d, in[ 2] + 0x6ed9eba1, 3); MD4STEP(F3, d, a, b, c, in[10] + 0x6ed9eba1, 9); MD4STEP(F3, c, d, a, b, in[ 6] + 0x6ed9eba1, 11); MD4STEP(F3, b, c, d, a, in[14] + 0x6ed9eba1, 15); MD4STEP(F3, a, b, c, d, in[ 1] + 0x6ed9eba1, 3); MD4STEP(F3, d, a, b, c, in[ 9] + 0x6ed9eba1, 9); MD4STEP(F3, c, d, a, b, in[ 5] + 0x6ed9eba1, 11); MD4STEP(F3, b, c, d, a, in[13] + 0x6ed9eba1, 15); MD4STEP(F3, a, b, c, d, in[ 3] + 0x6ed9eba1, 3); MD4STEP(F3, d, a, b, c, in[11] + 0x6ed9eba1, 9); MD4STEP(F3, c, d, a, b, in[ 7] + 0x6ed9eba1, 11); MD4STEP(F3, b, c, d, a, in[15] + 0x6ed9eba1, 15); state[0] += a; state[1] += b; state[2] += c; state[3] += d; }