/* * Cryptographic API. * * MD4 Message Digest Algorithm (RFC1320). * * Implementation derived from Andrew Tridgell and Steve French's * CIFS MD4 implementation, and the cryptoapi implementation * originally based on the public domain implementation written * by Colin Plumb in 1993. * * Copyright (c) Andrew Tridgell 1997-1998. * Modified by Steve French (sfrench@us.ibm.com) 2002 * Copyright (c) Cryptoapi developers. * Copyright (c) 2002 David S. Miller (davem@redhat.com) * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * */ #include <linux/init.h> #include <linux/crypto.h> #include <linux/kernel.h> #include <linux/string.h> #include <linux/types.h> #include <asm/byteorder.h> #define MD4_DIGEST_SIZE 16 #define MD4_HMAC_BLOCK_SIZE 64 #define MD4_BLOCK_WORDS 16 #define MD4_HASH_WORDS 4 struct md4_ctx { u32 hash[MD4_HASH_WORDS]; u32 block[MD4_BLOCK_WORDS]; u64 byte_count; }; static inline u32 lshift(u32 x, unsigned int s) { x &= 0xFFFFFFFF; return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s)); } static inline u32 F(u32 x, u32 y, u32 z) { return (x & y) | ((~x) & z); } static inline u32 G(u32 x, u32 y, u32 z) { return (x & y) | (x & z) | (y & z); } static inline u32 H(u32 x, u32 y, u32 z) { return x ^ y ^ z; } #define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s)) #define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s)) #define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s)) /* XXX: this stuff can be optimized */ static inline void le32_to_cpu_array(u32 *buf, unsigned int words) { while (words--) { __le32_to_cpus(buf); buf++; } } static inline void cpu_to_le32_array(u32 *buf, unsigned int words) { while (words--) { __cpu_to_le32s(buf); buf++; } } static void md4_transform(u32 *hash, u32 const *in) { u32 a, b, c, d; a = hash[0]; b = hash[1]; c = hash[2]; d = hash[3]; ROUND1(a, b, c, d, in[0], 3); ROUND1(d, a, b, c, in[1], 7); ROUND1(c, d, a, b, in[2], 11); ROUND1(b, c, d, a, in[3], 19); ROUND1(a, b, c, d, in[4], 3); ROUND1(d, a, b, c, in[5], 7); ROUND1(c, d, a, b, in[6], 11); ROUND1(b, c, d, a, in[7], 19); ROUND1(a, b, c, d, in[8], 3); ROUND1(d, a, b, c, in[9], 7); ROUND1(c, d, a, b, in[10], 11); ROUND1(b, c, d, a, in[11], 19); ROUND1(a, b, c, d, in[12], 3); ROUND1(d, a, b, c, in[13], 7); ROUND1(c, d, a, b, in[14], 11); ROUND1(b, c, d, a, in[15], 19); ROUND2(a, b, c, d,in[ 0], 3); ROUND2(d, a, b, c, in[4], 5); ROUND2(c, d, a, b, in[8], 9); ROUND2(b, c, d, a, in[12], 13); ROUND2(a, b, c, d, in[1], 3); ROUND2(d, a, b, c, in[5], 5); ROUND2(c, d, a, b, in[9], 9); ROUND2(b, c, d, a, in[13], 13); ROUND2(a, b, c, d, in[2], 3); ROUND2(d, a, b, c, in[6], 5); ROUND2(c, d, a, b, in[10], 9); ROUND2(b, c, d, a, in[14], 13); ROUND2(a, b, c, d, in[3], 3); ROUND2(d, a, b, c, in[7], 5); ROUND2(c, d, a, b, in[11], 9); ROUND2(b, c, d, a, in[15], 13); ROUND3(a, b, c, d,in[ 0], 3); ROUND3(d, a, b, c, in[8], 9); ROUND3(c, d, a, b, in[4], 11); ROUND3(b, c, d, a, in[12], 15); ROUND3(a, b, c, d, in[2], 3); ROUND3(d, a, b, c, in[10], 9); ROUND3(c, d, a, b, in[6], 11); ROUND3(b, c, d, a, in[14], 15); ROUND3(a, b, c, d, in[1], 3); ROUND3(d, a, b, c, in[9], 9); ROUND3(c, d, a, b, in[5], 11); ROUND3(b, c, d, a, in[13], 15); ROUND3(a, b, c, d, in[3], 3); ROUND3(d, a, b, c, in[11], 9); ROUND3(c, d, a, b, in[7], 11); ROUND3(b, c, d, a, in[15], 15); hash[0] += a; hash[1] += b; hash[2] += c; hash[3] += d; } static inline void md4_transform_helper(struct md4_ctx *ctx) { le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32)); md4_transform(ctx->hash, ctx->block); } static void md4_init(struct crypto_tfm *tfm) { struct md4_ctx *mctx = crypto_tfm_ctx(tfm); mctx->hash[0] = 0x67452301; mctx->hash[1] = 0xefcdab89; mctx->hash[2] = 0x98badcfe; mctx->hash[3] = 0x10325476; mctx->byte_count = 0; } static void md4_update(struct crypto_tfm *tfm, const u8 *data, unsigned int len) { struct md4_ctx *mctx = crypto_tfm_ctx(tfm); const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f); mctx->byte_count += len; if (avail > len) { memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), data, len); return; } memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), data, avail); md4_transform_helper(mctx); data += avail; len -= avail; while (len >= sizeof(mctx->block)) { memcpy(mctx->block, data, sizeof(mctx->block)); md4_transform_helper(mctx); data += sizeof(mctx->block); len -= sizeof(mctx->block); } memcpy(mctx->block, data, len); } static void md4_final(struct crypto_tfm *tfm, u8 *out) { struct md4_ctx *mctx = crypto_tfm_ctx(tfm); const unsigned int offset = mctx->byte_count & 0x3f; char *p = (char *)mctx->block + offset; int padding = 56 - (offset + 1); *p++ = 0x80; if (padding < 0) { memset(p, 0x00, padding + sizeof (u64)); md4_transform_helper(mctx); p = (char *)mctx->block; padding = 56; } memset(p, 0, padding); mctx->block[14] = mctx->byte_count << 3; mctx->block[15] = mctx->byte_count >> 29; le32_to_cpu_array(mctx->block, (sizeof(mctx->block) - sizeof(u64)) / sizeof(u32)); md4_transform(mctx->hash, mctx->block); cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32)); memcpy(out, mctx->hash, sizeof(mctx->hash)); memset(mctx, 0, sizeof(*mctx)); } static struct crypto_alg alg = { .cra_name = "md4", .cra_flags = CRYPTO_ALG_TYPE_DIGEST, .cra_blocksize = MD4_HMAC_BLOCK_SIZE, .cra_ctxsize = sizeof(struct md4_ctx), .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(alg.cra_list), .cra_u = { .digest = { .dia_digestsize = MD4_DIGEST_SIZE, .dia_init = md4_init, .dia_update = md4_update, .dia_final = md4_final } } }; static int __init init(void) { return crypto_register_alg(&alg); } static void __exit fini(void) { crypto_unregister_alg(&alg); } module_init(init); module_exit(fini); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("MD4 Message Digest Algorithm");