/*
* MD5 hash implementation and interface functions
* Copyright (c) 2003-2005, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "includes.h"
#include "common.h"
#include "md5.h"
#include "crypto.h"
/**
* hmac_md5_vector - HMAC-MD5 over data vector (RFC 2104)
* @key: Key for HMAC operations
* @key_len: Length of the key in bytes
* @num_elem: Number of elements in the data vector
* @addr: Pointers to the data areas
* @len: Lengths of the data blocks
* @mac: Buffer for the hash (16 bytes)
*/
void hmac_md5_vector(const u8 *key, size_t key_len, size_t num_elem,
const u8 *addr[], const size_t *len, u8 *mac)
{
u8 k_pad[64]; /* padding - key XORd with ipad/opad */
u8 tk[16];
const u8 *_addr[6];
size_t i, _len[6];
if (num_elem > 5) {
/*
* Fixed limit on the number of fragments to avoid having to
* allocate memory (which could fail).
*/
return;
}
/* if key is longer than 64 bytes reset it to key = MD5(key) */
if (key_len > 64) {
md5_vector(1, &key, &key_len, tk);
key = tk;
key_len = 16;
}
/* the HMAC_MD5 transform looks like:
*
* MD5(K XOR opad, MD5(K XOR ipad, text))
*
* where K is an n byte key
* ipad is the byte 0x36 repeated 64 times
* opad is the byte 0x5c repeated 64 times
* and text is the data being protected */
/* start out by storing key in ipad */
os_memset(k_pad, 0, sizeof(k_pad));
os_memcpy(k_pad, key, key_len);
/* XOR key with ipad values */
for (i = 0; i < 64; i++)
k_pad[i] ^= 0x36;
/* perform inner MD5 */
_addr[0] = k_pad;
_len[0] = 64;
for (i = 0; i < num_elem; i++) {
_addr[i + 1] = addr[i];
_len[i + 1] = len[i];
}
md5_vector(1 + num_elem, _addr, _len, mac);
os_memset(k_pad, 0, sizeof(k_pad));
os_memcpy(k_pad, key, key_len);
/* XOR key with opad values */
for (i = 0; i < 64; i++)
k_pad[i] ^= 0x5c;
/* perform outer MD5 */
_addr[0] = k_pad;
_len[0] = 64;
_addr[1] = mac;
_len[1] = MD5_MAC_LEN;
md5_vector(2, _addr, _len, mac);
}
/**
* hmac_md5 - HMAC-MD5 over data buffer (RFC 2104)
* @key: Key for HMAC operations
* @key_len: Length of the key in bytes
* @data: Pointers to the data area
* @data_len: Length of the data area
* @mac: Buffer for the hash (16 bytes)
*/
void hmac_md5(const u8 *key, size_t key_len, const u8 *data, size_t data_len,
u8 *mac)
{
hmac_md5_vector(key, key_len, 1, &data, &data_len, mac);
}
#ifdef INTERNAL_MD5
struct MD5Context {
u32 buf[4];
u32 bits[2];
u8 in[64];
};
#ifndef CONFIG_CRYPTO_INTERNAL
static void MD5Init(struct MD5Context *context);
static void MD5Update(struct MD5Context *context, unsigned char const *buf,
unsigned len);
static void MD5Final(unsigned char digest[16], struct MD5Context *context);
#endif /* CONFIG_CRYPTO_INTERNAL */
static void MD5Transform(u32 buf[4], u32 const in[16]);
typedef struct MD5Context MD5_CTX;
/**
* md5_vector - MD5 hash for data vector
* @num_elem: Number of elements in the data vector
* @addr: Pointers to the data areas
* @len: Lengths of the data blocks
* @mac: Buffer for the hash
*/
void md5_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
MD5_CTX ctx;
size_t i;
MD5Init(&ctx);
for (i = 0; i < num_elem; i++)
MD5Update(&ctx, addr[i], len[i]);
MD5Final(mac, &ctx);
}
/* ===== start - public domain MD5 implementation ===== */
/*
* This code implements the MD5 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.
*
* 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
* MD5Context structure, pass it to MD5Init, call MD5Update as
* needed on buffers full of bytes, and then call MD5Final, which
* will fill a supplied 16-byte array with the digest.
*/
#ifndef WORDS_BIGENDIAN
#define byteReverse(buf, len) /* Nothing */
#else
/*
* Note: this code is harmless on little-endian machines.
*/
static void byteReverse(unsigned char *buf, unsigned longs)
{
u32 t;
do {
t = (u32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
((unsigned) buf[1] << 8 | buf[0]);
*(u32 *) buf = t;
buf += 4;
} while (--longs);
}
#endif
/*
* Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
* initialization constants.
*/
void MD5Init(struct MD5Context *ctx)
{
ctx->buf[0] = 0x67452301;
ctx->buf[1] = 0xefcdab89;
ctx->buf[2] = 0x98badcfe;
ctx->buf[3] = 0x10325476;
ctx->bits[0] = 0;
ctx->bits[1] = 0;
}
/*
* Update context to reflect the concatenation of another buffer full
* of bytes.
*/
void MD5Update(struct MD5Context *ctx, unsigned char const *buf, unsigned len)
{
u32 t;
/* Update bitcount */
t = ctx->bits[0];
if ((ctx->bits[0] = t + ((u32) len << 3)) < t)
ctx->bits[1]++; /* Carry from low to high */
ctx->bits[1] += len >> 29;
t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
/* Handle any leading odd-sized chunks */
if (t) {
unsigned char *p = (unsigned char *) ctx->in + t;
t = 64 - t;
if (len < t) {
os_memcpy(p, buf, len);
return;
}
os_memcpy(p, buf, t);
byteReverse(ctx->in, 16);
MD5Transform(ctx->buf, (u32 *) ctx->in);
buf += t;
len -= t;
}
/* Process data in 64-byte chunks */
while (len >= 64) {
os_memcpy(ctx->in, buf, 64);
byteReverse(ctx->in, 16);
MD5Transform(ctx->buf, (u32 *) ctx->in);
buf += 64;
len -= 64;
}
/* Handle any remaining bytes of data. */
os_memcpy(ctx->in, buf, len);
}
/*
* Final wrapup - pad to 64-byte boundary with the bit pattern
* 1 0* (64-bit count of bits processed, MSB-first)
*/
void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
{
unsigned count;
unsigned char *p;
/* Compute number of bytes mod 64 */
count = (ctx->bits[0] >> 3) & 0x3F;
/* Set the first char of padding to 0x80. This is safe since there is
always at least one byte free */
p = ctx->in + count;
*p++ = 0x80;
/* Bytes of padding needed to make 64 bytes */
count = 64 - 1 - count;
/* Pad out to 56 mod 64 */
if (count < 8) {
/* Two lots of padding: Pad the first block to 64 bytes */
os_memset(p, 0, count);
byteReverse(ctx->in, 16);
MD5Transform(ctx->buf, (u32 *) ctx->in);
/* Now fill the next block with 56 bytes */
os_memset(ctx->in, 0, 56);
} else {
/* Pad block to 56 bytes */
os_memset(p, 0, count - 8);
}
byteReverse(ctx->in, 14);
/* Append length in bits and transform */
((u32 *) ctx->in)[14] = ctx->bits[0];
((u32 *) ctx->in)[15] = ctx->bits[1];
MD5Transform(ctx->buf, (u32 *) ctx->in);
byteReverse((unsigned char *) ctx->buf, 4);
os_memcpy(digest, ctx->buf, 16);
os_memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */
}
/* The four 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) F1(z, x, y)
#define F3(x, y, z) (x ^ y ^ z)
#define F4(x, y, z) (y ^ (x | ~z))
/* This is the central step in the MD5 algorithm. */
#define MD5STEP(f, w, x, y, z, data, s) \
( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
/*
* The core of the MD5 algorithm, this alters an existing MD5 hash to
* reflect the addition of 16 longwords of new data. MD5Update blocks
* the data and converts bytes into longwords for this routine.
*/
static void MD5Transform(u32 buf[4], u32 const in[16])
{
register u32 a, b, c, d;
a = buf[0];
b = buf[1];
c = buf[2];
d = buf[3];
MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
buf[0] += a;
buf[1] += b;
buf[2] += c;
buf[3] += d;
}
/* ===== end - public domain MD5 implementation ===== */
#endif /* INTERNAL_MD5 */