fs/smbfs_common/cifs_md4.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * Cryptographic API.
0004  *
0005  * MD4 Message Digest Algorithm (RFC1320).
0006  *
0007  * Implementation derived from Andrew Tridgell and Steve French's
0008  * CIFS MD4 implementation, and the cryptoapi implementation
0009  * originally based on the public domain implementation written
0010  * by Colin Plumb in 1993.
0011  *
0012  * Copyright (c) Andrew Tridgell 1997-1998.
0013  * Modified by Steve French (sfrench@us.ibm.com) 2002
0014  * Copyright (c) Cryptoapi developers.
0015  * Copyright (c) 2002 David S. Miller (davem@redhat.com)
0016  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
0017  *
0018  */
0019 #include <linux/init.h>
0020 #include <linux/kernel.h>
0021 #include <linux/module.h>
0022 #include <linux/string.h>
0023 #include <linux/types.h>
0024 #include <asm/byteorder.h>
0025 #include "md4.h"
0026
0027 MODULE_LICENSE("GPL");
0028
0029 static inline u32 lshift(u32 x, unsigned int s)
0030 {
0031     x &= 0xFFFFFFFF;
0032     return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s));
0033 }
0034
0035 static inline u32 F(u32 x, u32 y, u32 z)
0036 {
0037     return (x & y) | ((~x) & z);
0038 }
0039
0040 static inline u32 G(u32 x, u32 y, u32 z)
0041 {
0042     return (x & y) | (x & z) | (y & z);
0043 }
0044
0045 static inline u32 H(u32 x, u32 y, u32 z)
0046 {
0047     return x ^ y ^ z;
0048 }
0049
0050 #define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s))
0051 #define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s))
0052 #define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s))
0053
0054 static void md4_transform(u32 *hash, u32 const *in)
0055 {
0056     u32 a, b, c, d;
0057
0058     a = hash[0];
0059     b = hash[1];
0060     c = hash[2];
0061     d = hash[3];
0062
0063     ROUND1(a, b, c, d, in[0], 3);
0064     ROUND1(d, a, b, c, in[1], 7);
0065     ROUND1(c, d, a, b, in[2], 11);
0066     ROUND1(b, c, d, a, in[3], 19);
0067     ROUND1(a, b, c, d, in[4], 3);
0068     ROUND1(d, a, b, c, in[5], 7);
0069     ROUND1(c, d, a, b, in[6], 11);
0070     ROUND1(b, c, d, a, in[7], 19);
0071     ROUND1(a, b, c, d, in[8], 3);
0072     ROUND1(d, a, b, c, in[9], 7);
0073     ROUND1(c, d, a, b, in[10], 11);
0074     ROUND1(b, c, d, a, in[11], 19);
0075     ROUND1(a, b, c, d, in[12], 3);
0076     ROUND1(d, a, b, c, in[13], 7);
0077     ROUND1(c, d, a, b, in[14], 11);
0078     ROUND1(b, c, d, a, in[15], 19);
0079
0080     ROUND2(a, b, c, d, in[0], 3);
0081     ROUND2(d, a, b, c, in[4], 5);
0082     ROUND2(c, d, a, b, in[8], 9);
0083     ROUND2(b, c, d, a, in[12], 13);
0084     ROUND2(a, b, c, d, in[1], 3);
0085     ROUND2(d, a, b, c, in[5], 5);
0086     ROUND2(c, d, a, b, in[9], 9);
0087     ROUND2(b, c, d, a, in[13], 13);
0088     ROUND2(a, b, c, d, in[2], 3);
0089     ROUND2(d, a, b, c, in[6], 5);
0090     ROUND2(c, d, a, b, in[10], 9);
0091     ROUND2(b, c, d, a, in[14], 13);
0092     ROUND2(a, b, c, d, in[3], 3);
0093     ROUND2(d, a, b, c, in[7], 5);
0094     ROUND2(c, d, a, b, in[11], 9);
0095     ROUND2(b, c, d, a, in[15], 13);
0096
0097     ROUND3(a, b, c, d, in[0], 3);
0098     ROUND3(d, a, b, c, in[8], 9);
0099     ROUND3(c, d, a, b, in[4], 11);
0100     ROUND3(b, c, d, a, in[12], 15);
0101     ROUND3(a, b, c, d, in[2], 3);
0102     ROUND3(d, a, b, c, in[10], 9);
0103     ROUND3(c, d, a, b, in[6], 11);
0104     ROUND3(b, c, d, a, in[14], 15);
0105     ROUND3(a, b, c, d, in[1], 3);
0106     ROUND3(d, a, b, c, in[9], 9);
0107     ROUND3(c, d, a, b, in[5], 11);
0108     ROUND3(b, c, d, a, in[13], 15);
0109     ROUND3(a, b, c, d, in[3], 3);
0110     ROUND3(d, a, b, c, in[11], 9);
0111     ROUND3(c, d, a, b, in[7], 11);
0112     ROUND3(b, c, d, a, in[15], 15);
0113
0114     hash[0] += a;
0115     hash[1] += b;
0116     hash[2] += c;
0117     hash[3] += d;
0118 }
0119
0120 static inline void md4_transform_helper(struct md4_ctx *ctx)
0121 {
0122     le32_to_cpu_array(ctx->block, ARRAY_SIZE(ctx->block));
0123     md4_transform(ctx->hash, ctx->block);
0124 }
0125
0126 int cifs_md4_init(struct md4_ctx *mctx)
0127 {
0128     memset(mctx, 0, sizeof(struct md4_ctx));
0129     mctx->hash[0] = 0x67452301;
0130     mctx->hash[1] = 0xefcdab89;
0131     mctx->hash[2] = 0x98badcfe;
0132     mctx->hash[3] = 0x10325476;
0133     mctx->byte_count = 0;
0134
0135     return 0;
0136 }
0137 EXPORT_SYMBOL_GPL(cifs_md4_init);
0138
0139 int cifs_md4_update(struct md4_ctx *mctx, const u8 *data, unsigned int len)
0140 {
0141     const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
0142
0143     mctx->byte_count += len;
0144
0145     if (avail > len) {
0146         memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
0147                data, len);
0148         return 0;
0149     }
0150
0151     memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
0152            data, avail);
0153
0154     md4_transform_helper(mctx);
0155     data += avail;
0156     len -= avail;
0157
0158     while (len >= sizeof(mctx->block)) {
0159         memcpy(mctx->block, data, sizeof(mctx->block));
0160         md4_transform_helper(mctx);
0161         data += sizeof(mctx->block);
0162         len -= sizeof(mctx->block);
0163     }
0164
0165     memcpy(mctx->block, data, len);
0166
0167     return 0;
0168 }
0169 EXPORT_SYMBOL_GPL(cifs_md4_update);
0170
0171 int cifs_md4_final(struct md4_ctx *mctx, u8 *out)
0172 {
0173     const unsigned int offset = mctx->byte_count & 0x3f;
0174     char *p = (char *)mctx->block + offset;
0175     int padding = 56 - (offset + 1);
0176
0177     *p++ = 0x80;
0178     if (padding < 0) {
0179         memset(p, 0x00, padding + sizeof(u64));
0180         md4_transform_helper(mctx);
0181         p = (char *)mctx->block;
0182         padding = 56;
0183     }
0184
0185     memset(p, 0, padding);
0186     mctx->block[14] = mctx->byte_count << 3;
0187     mctx->block[15] = mctx->byte_count >> 29;
0188     le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
0189               sizeof(u64)) / sizeof(u32));
0190     md4_transform(mctx->hash, mctx->block);
0191     cpu_to_le32_array(mctx->hash, ARRAY_SIZE(mctx->hash));
0192     memcpy(out, mctx->hash, sizeof(mctx->hash));
0193     memset(mctx, 0, sizeof(*mctx));
0194
0195     return 0;
0196 }
0197 EXPORT_SYMBOL_GPL(cifs_md4_final);