#### Other Tools

```/* vim:set ts=2 sw=2 et cindent: */ ```
```/* This Source Code Form is subject to the terms of the Mozilla Public ```
``` * License, v. 2.0. If a copy of the MPL was not distributed with this ```
``` * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ ```
``` ```
```/* ```
``` * "clean room" MD4 implementation (see RFC 1320) ```
``` */ ```
``` ```
```#include <string.h> ```
```#include "md4.h" ```
``` ```
```/* the "conditional" function */ ```
```#define F(x, y, z) (((x) & (y)) | (~(x) & (z))) ```
``` ```
```/* the "majority" function */ ```
```#define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z))) ```
``` ```
```/* the "parity" function */ ```
```#define H(x, y, z) ((x) ^ (y) ^ (z)) ```
``` ```
```/* rotate n-bits to the left */ ```
```#define ROTL(x, n) (((x) << (n)) | ((x) >> (0x20 - n))) ```
``` ```
```/* round 1: [abcd k s]: a = (a + F(b,c,d) + X[k]) <<< s */ ```
```#define RD1(a, b, c, d, k, s) \ ```
``` a += F(b, c, d) + X[k]; \ ```
``` a = ROTL(a, s) ```
``` ```
```/* round 2: [abcd k s]: a = (a + G(b,c,d) + X[k] + MAGIC) <<< s */ ```
```#define RD2(a, b, c, d, k, s) \ ```
``` a += G(b, c, d) + X[k] + 0x5A827999; \ ```
``` a = ROTL(a, s) ```
``` ```
```/* round 3: [abcd k s]: a = (a + H(b,c,d) + X[k] + MAGIC) <<< s */ ```
```#define RD3(a, b, c, d, k, s) \ ```
``` a += H(b, c, d) + X[k] + 0x6ED9EBA1; \ ```
``` a = ROTL(a, s) ```
``` ```
```/* converts from word array to byte array, len is number of bytes */ ```
```static void w2b(uint8_t* out, const uint32_t* in, uint32_t len) { ```
``` uint8_t* bp; ```
``` const uint32_t *wp, *wpend; ```
``` ```
``` bp = out; ```
``` wp = in; ```
``` wpend = wp + (len >> 2); ```
``` ```
``` for (; wp != wpend; ++wp, bp += 4) { ```
``` bp[0] = (uint8_t)((*wp) & 0xFF); ```
``` bp[1] = (uint8_t)((*wp >> 8) & 0xFF); ```
``` bp[2] = (uint8_t)((*wp >> 16) & 0xFF); ```
``` bp[3] = (uint8_t)((*wp >> 24) & 0xFF); ```
``` } ```
```} ```
``` ```
```/* converts from byte array to word array, len is number of bytes */ ```
```static void b2w(uint32_t* out, const uint8_t* in, uint32_t len) { ```
``` uint32_t* wp; ```
``` const uint8_t *bp, *bpend; ```
``` ```
``` wp = out; ```
``` bp = in; ```
``` bpend = in + len; ```
``` ```
``` for (; bp != bpend; bp += 4, ++wp) { ```
``` *wp = (uint32_t)bp[0] | ((uint32_t)bp[1] << 8) | ((uint32_t)bp[2] << 16) | ```
``` ((uint32_t)bp[3] << 24); ```
``` } ```
```} ```
``` ```
```/* update state: data is 64 bytes in length */ ```
```static void md4step(uint32_t state[4], const uint8_t* data) { ```
``` uint32_t A, B, C, D, X[16]; ```
``` ```
``` b2w(X, data, 64); ```
``` ```
``` A = state[0]; ```
``` B = state[1]; ```
``` C = state[2]; ```
``` D = state[3]; ```
``` ```
``` RD1(A, B, C, D, 0, 3); ```
``` RD1(D, A, B, C, 1, 7); ```
``` RD1(C, D, A, B, 2, 11); ```
``` RD1(B, C, D, A, 3, 19); ```
``` RD1(A, B, C, D, 4, 3); ```
``` RD1(D, A, B, C, 5, 7); ```
``` RD1(C, D, A, B, 6, 11); ```
``` RD1(B, C, D, A, 7, 19); ```
``` RD1(A, B, C, D, 8, 3); ```
``` RD1(D, A, B, C, 9, 7); ```
``` RD1(C, D, A, B, 10, 11); ```
``` RD1(B, C, D, A, 11, 19); ```
``` RD1(A, B, C, D, 12, 3); ```
``` RD1(D, A, B, C, 13, 7); ```
``` RD1(C, D, A, B, 14, 11); ```
``` RD1(B, C, D, A, 15, 19); ```
``` ```
``` RD2(A, B, C, D, 0, 3); ```
``` RD2(D, A, B, C, 4, 5); ```
``` RD2(C, D, A, B, 8, 9); ```
``` RD2(B, C, D, A, 12, 13); ```
``` RD2(A, B, C, D, 1, 3); ```
``` RD2(D, A, B, C, 5, 5); ```
``` RD2(C, D, A, B, 9, 9); ```
``` RD2(B, C, D, A, 13, 13); ```
``` RD2(A, B, C, D, 2, 3); ```
``` RD2(D, A, B, C, 6, 5); ```
``` RD2(C, D, A, B, 10, 9); ```
``` RD2(B, C, D, A, 14, 13); ```
``` RD2(A, B, C, D, 3, 3); ```
``` RD2(D, A, B, C, 7, 5); ```
``` RD2(C, D, A, B, 11, 9); ```
``` RD2(B, C, D, A, 15, 13); ```
``` ```
``` RD3(A, B, C, D, 0, 3); ```
``` RD3(D, A, B, C, 8, 9); ```
``` RD3(C, D, A, B, 4, 11); ```
``` RD3(B, C, D, A, 12, 15); ```
``` RD3(A, B, C, D, 2, 3); ```
``` RD3(D, A, B, C, 10, 9); ```
``` RD3(C, D, A, B, 6, 11); ```
``` RD3(B, C, D, A, 14, 15); ```
``` RD3(A, B, C, D, 1, 3); ```
``` RD3(D, A, B, C, 9, 9); ```
``` RD3(C, D, A, B, 5, 11); ```
``` RD3(B, C, D, A, 13, 15); ```
``` RD3(A, B, C, D, 3, 3); ```
``` RD3(D, A, B, C, 11, 9); ```
``` RD3(C, D, A, B, 7, 11); ```
``` RD3(B, C, D, A, 15, 15); ```
``` ```
``` state[0] += A; ```
``` state[1] += B; ```
``` state[2] += C; ```
``` state[3] += D; ```
```} ```
``` ```
```void md4sum(const uint8_t* input, uint32_t inputLen, uint8_t* result) { ```
``` uint8_t final[128]; ```
``` uint32_t i, n, m, state[4]; ```
``` uint64_t inputLenBits; ```
``` uint32_t inputLenBitsLow; ```
``` uint32_t inputLenBitsHigh; ```
``` ```
``` /* magic initial states */ ```
``` state[0] = 0x67452301; ```
``` state[1] = 0xEFCDAB89; ```
``` state[2] = 0x98BADCFE; ```
``` state[3] = 0x10325476; ```
``` ```
``` /* compute number of complete 64-byte segments contained in input */ ```
``` m = inputLen >> 6; ```
``` ```
``` /* digest first m segments */ ```
``` for (i = 0; i < m; ++i) md4step(state, (input + (i << 6))); ```
``` ```
``` /* build final buffer */ ```
``` n = inputLen % 64; ```
``` memcpy(final, input + (m << 6), n); ```
``` final[n] = 0x80; ```
``` memset(final + n + 1, 0, 120 - (n + 1)); ```
``` ```
``` /* Append the original input length in bits as a 64-bit number. This is done ```
``` * in two 32-bit chunks, with the least-significant 32 bits first. ```
``` * w2b will handle endianness. */ ```
``` inputLenBits = inputLen << 3; ```
``` inputLenBitsLow = (uint32_t)(inputLenBits & 0xFFFFFFFF); ```
``` w2b(final + (n >= 56 ? 120 : 56), &inputLenBitsLow, 4); ```
``` inputLenBitsHigh = (uint32_t)((inputLenBits >> 32) & 0xFFFFFFFF); ```
``` w2b(final + (n >= 56 ? 124 : 60), &inputLenBitsHigh, 4); ```
``` ```
``` md4step(state, final); ```
``` if (n >= 56) md4step(state, final + 64); ```
``` ```
``` /* copy state to result */ ```
``` w2b(result, state, 16); ```
```} ```