1 /*
2  * Cryptographic API.
3  *
4  * MD5 Message Digest Algorithm (RFC1321).
5  *
6  * Adapted for OCTEON by Aaro Koskinen <aaro.koskinen@iki.fi>.
7  *
8  * Based on crypto/md5.c, which is:
9  *
10  * Derived from cryptoapi implementation, originally based on the
11  * public domain implementation written by Colin Plumb in 1993.
12  *
13  * Copyright (c) Cryptoapi developers.
14  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
15  *
16  * This program is free software; you can redistribute it and/or modify it
17  * under the terms of the GNU General Public License as published by the Free
18  * Software Foundation; either version 2 of the License, or (at your option)
19  * any later version.
20  */
21 
22 #include <crypto/md5.h>
23 #include <linux/init.h>
24 #include <linux/types.h>
25 #include <linux/module.h>
26 #include <linux/string.h>
27 #include <asm/byteorder.h>
28 #include <linux/cryptohash.h>
29 #include <asm/octeon/octeon.h>
30 #include <crypto/internal/hash.h>
31 
32 #include "octeon-crypto.h"
33 
34 /*
35  * We pass everything as 64-bit. OCTEON can handle misaligned data.
36  */
37 
38 static void octeon_md5_store_hash(struct md5_state *ctx)
39 {
40 	u64 *hash = (u64 *)ctx->hash;
41 
42 	write_octeon_64bit_hash_dword(hash[0], 0);
43 	write_octeon_64bit_hash_dword(hash[1], 1);
44 }
45 
46 static void octeon_md5_read_hash(struct md5_state *ctx)
47 {
48 	u64 *hash = (u64 *)ctx->hash;
49 
50 	hash[0] = read_octeon_64bit_hash_dword(0);
51 	hash[1] = read_octeon_64bit_hash_dword(1);
52 }
53 
54 static void octeon_md5_transform(const void *_block)
55 {
56 	const u64 *block = _block;
57 
58 	write_octeon_64bit_block_dword(block[0], 0);
59 	write_octeon_64bit_block_dword(block[1], 1);
60 	write_octeon_64bit_block_dword(block[2], 2);
61 	write_octeon_64bit_block_dword(block[3], 3);
62 	write_octeon_64bit_block_dword(block[4], 4);
63 	write_octeon_64bit_block_dword(block[5], 5);
64 	write_octeon_64bit_block_dword(block[6], 6);
65 	octeon_md5_start(block[7]);
66 }
67 
68 static int octeon_md5_init(struct shash_desc *desc)
69 {
70 	struct md5_state *mctx = shash_desc_ctx(desc);
71 
72 	mctx->hash[0] = cpu_to_le32(MD5_H0);
73 	mctx->hash[1] = cpu_to_le32(MD5_H1);
74 	mctx->hash[2] = cpu_to_le32(MD5_H2);
75 	mctx->hash[3] = cpu_to_le32(MD5_H3);
76 	mctx->byte_count = 0;
77 
78 	return 0;
79 }
80 
81 static int octeon_md5_update(struct shash_desc *desc, const u8 *data,
82 			     unsigned int len)
83 {
84 	struct md5_state *mctx = shash_desc_ctx(desc);
85 	const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
86 	struct octeon_cop2_state state;
87 	unsigned long flags;
88 
89 	mctx->byte_count += len;
90 
91 	if (avail > len) {
92 		memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
93 		       data, len);
94 		return 0;
95 	}
96 
97 	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), data,
98 	       avail);
99 
100 	flags = octeon_crypto_enable(&state);
101 	octeon_md5_store_hash(mctx);
102 
103 	octeon_md5_transform(mctx->block);
104 	data += avail;
105 	len -= avail;
106 
107 	while (len >= sizeof(mctx->block)) {
108 		octeon_md5_transform(data);
109 		data += sizeof(mctx->block);
110 		len -= sizeof(mctx->block);
111 	}
112 
113 	octeon_md5_read_hash(mctx);
114 	octeon_crypto_disable(&state, flags);
115 
116 	memcpy(mctx->block, data, len);
117 
118 	return 0;
119 }
120 
121 static int octeon_md5_final(struct shash_desc *desc, u8 *out)
122 {
123 	struct md5_state *mctx = shash_desc_ctx(desc);
124 	const unsigned int offset = mctx->byte_count & 0x3f;
125 	char *p = (char *)mctx->block + offset;
126 	int padding = 56 - (offset + 1);
127 	struct octeon_cop2_state state;
128 	unsigned long flags;
129 
130 	*p++ = 0x80;
131 
132 	flags = octeon_crypto_enable(&state);
133 	octeon_md5_store_hash(mctx);
134 
135 	if (padding < 0) {
136 		memset(p, 0x00, padding + sizeof(u64));
137 		octeon_md5_transform(mctx->block);
138 		p = (char *)mctx->block;
139 		padding = 56;
140 	}
141 
142 	memset(p, 0, padding);
143 	mctx->block[14] = cpu_to_le32(mctx->byte_count << 3);
144 	mctx->block[15] = cpu_to_le32(mctx->byte_count >> 29);
145 	octeon_md5_transform(mctx->block);
146 
147 	octeon_md5_read_hash(mctx);
148 	octeon_crypto_disable(&state, flags);
149 
150 	memcpy(out, mctx->hash, sizeof(mctx->hash));
151 	memset(mctx, 0, sizeof(*mctx));
152 
153 	return 0;
154 }
155 
156 static int octeon_md5_export(struct shash_desc *desc, void *out)
157 {
158 	struct md5_state *ctx = shash_desc_ctx(desc);
159 
160 	memcpy(out, ctx, sizeof(*ctx));
161 	return 0;
162 }
163 
164 static int octeon_md5_import(struct shash_desc *desc, const void *in)
165 {
166 	struct md5_state *ctx = shash_desc_ctx(desc);
167 
168 	memcpy(ctx, in, sizeof(*ctx));
169 	return 0;
170 }
171 
172 static struct shash_alg alg = {
173 	.digestsize	=	MD5_DIGEST_SIZE,
174 	.init		=	octeon_md5_init,
175 	.update		=	octeon_md5_update,
176 	.final		=	octeon_md5_final,
177 	.export		=	octeon_md5_export,
178 	.import		=	octeon_md5_import,
179 	.descsize	=	sizeof(struct md5_state),
180 	.statesize	=	sizeof(struct md5_state),
181 	.base		=	{
182 		.cra_name	=	"md5",
183 		.cra_driver_name=	"octeon-md5",
184 		.cra_priority	=	OCTEON_CR_OPCODE_PRIORITY,
185 		.cra_blocksize	=	MD5_HMAC_BLOCK_SIZE,
186 		.cra_module	=	THIS_MODULE,
187 	}
188 };
189 
190 static int __init md5_mod_init(void)
191 {
192 	if (!octeon_has_crypto())
193 		return -ENOTSUPP;
194 	return crypto_register_shash(&alg);
195 }
196 
197 static void __exit md5_mod_fini(void)
198 {
199 	crypto_unregister_shash(&alg);
200 }
201 
202 module_init(md5_mod_init);
203 module_exit(md5_mod_fini);
204 
205 MODULE_LICENSE("GPL");
206 MODULE_DESCRIPTION("MD5 Message Digest Algorithm (OCTEON)");
207 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
208