1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Glue code for MD5 implementation for PPC assembler
4 *
5 * Based on generic implementation.
6 *
7 * Copyright (c) 2015 Markus Stockhausen <stockhausen@collogia.de>
8 */
9
10 #include <crypto/internal/hash.h>
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/mm.h>
14 #include <linux/cryptohash.h>
15 #include <linux/types.h>
16 #include <crypto/md5.h>
17 #include <asm/byteorder.h>
18
19 extern void ppc_md5_transform(u32 *state, const u8 *src, u32 blocks);
20
ppc_md5_clear_context(struct md5_state * sctx)21 static inline void ppc_md5_clear_context(struct md5_state *sctx)
22 {
23 int count = sizeof(struct md5_state) >> 2;
24 u32 *ptr = (u32 *)sctx;
25
26 /* make sure we can clear the fast way */
27 BUILD_BUG_ON(sizeof(struct md5_state) % 4);
28 do { *ptr++ = 0; } while (--count);
29 }
30
ppc_md5_init(struct shash_desc * desc)31 static int ppc_md5_init(struct shash_desc *desc)
32 {
33 struct md5_state *sctx = shash_desc_ctx(desc);
34
35 sctx->hash[0] = MD5_H0;
36 sctx->hash[1] = MD5_H1;
37 sctx->hash[2] = MD5_H2;
38 sctx->hash[3] = MD5_H3;
39 sctx->byte_count = 0;
40
41 return 0;
42 }
43
ppc_md5_update(struct shash_desc * desc,const u8 * data,unsigned int len)44 static int ppc_md5_update(struct shash_desc *desc, const u8 *data,
45 unsigned int len)
46 {
47 struct md5_state *sctx = shash_desc_ctx(desc);
48 const unsigned int offset = sctx->byte_count & 0x3f;
49 unsigned int avail = 64 - offset;
50 const u8 *src = data;
51
52 sctx->byte_count += len;
53
54 if (avail > len) {
55 memcpy((char *)sctx->block + offset, src, len);
56 return 0;
57 }
58
59 if (offset) {
60 memcpy((char *)sctx->block + offset, src, avail);
61 ppc_md5_transform(sctx->hash, (const u8 *)sctx->block, 1);
62 len -= avail;
63 src += avail;
64 }
65
66 if (len > 63) {
67 ppc_md5_transform(sctx->hash, src, len >> 6);
68 src += len & ~0x3f;
69 len &= 0x3f;
70 }
71
72 memcpy((char *)sctx->block, src, len);
73 return 0;
74 }
75
ppc_md5_final(struct shash_desc * desc,u8 * out)76 static int ppc_md5_final(struct shash_desc *desc, u8 *out)
77 {
78 struct md5_state *sctx = shash_desc_ctx(desc);
79 const unsigned int offset = sctx->byte_count & 0x3f;
80 const u8 *src = (const u8 *)sctx->block;
81 u8 *p = (u8 *)src + offset;
82 int padlen = 55 - offset;
83 __le64 *pbits = (__le64 *)((char *)sctx->block + 56);
84 __le32 *dst = (__le32 *)out;
85
86 *p++ = 0x80;
87
88 if (padlen < 0) {
89 memset(p, 0x00, padlen + sizeof (u64));
90 ppc_md5_transform(sctx->hash, src, 1);
91 p = (char *)sctx->block;
92 padlen = 56;
93 }
94
95 memset(p, 0, padlen);
96 *pbits = cpu_to_le64(sctx->byte_count << 3);
97 ppc_md5_transform(sctx->hash, src, 1);
98
99 dst[0] = cpu_to_le32(sctx->hash[0]);
100 dst[1] = cpu_to_le32(sctx->hash[1]);
101 dst[2] = cpu_to_le32(sctx->hash[2]);
102 dst[3] = cpu_to_le32(sctx->hash[3]);
103
104 ppc_md5_clear_context(sctx);
105 return 0;
106 }
107
ppc_md5_export(struct shash_desc * desc,void * out)108 static int ppc_md5_export(struct shash_desc *desc, void *out)
109 {
110 struct md5_state *sctx = shash_desc_ctx(desc);
111
112 memcpy(out, sctx, sizeof(*sctx));
113 return 0;
114 }
115
ppc_md5_import(struct shash_desc * desc,const void * in)116 static int ppc_md5_import(struct shash_desc *desc, const void *in)
117 {
118 struct md5_state *sctx = shash_desc_ctx(desc);
119
120 memcpy(sctx, in, sizeof(*sctx));
121 return 0;
122 }
123
124 static struct shash_alg alg = {
125 .digestsize = MD5_DIGEST_SIZE,
126 .init = ppc_md5_init,
127 .update = ppc_md5_update,
128 .final = ppc_md5_final,
129 .export = ppc_md5_export,
130 .import = ppc_md5_import,
131 .descsize = sizeof(struct md5_state),
132 .statesize = sizeof(struct md5_state),
133 .base = {
134 .cra_name = "md5",
135 .cra_driver_name= "md5-ppc",
136 .cra_priority = 200,
137 .cra_blocksize = MD5_HMAC_BLOCK_SIZE,
138 .cra_module = THIS_MODULE,
139 }
140 };
141
ppc_md5_mod_init(void)142 static int __init ppc_md5_mod_init(void)
143 {
144 return crypto_register_shash(&alg);
145 }
146
ppc_md5_mod_fini(void)147 static void __exit ppc_md5_mod_fini(void)
148 {
149 crypto_unregister_shash(&alg);
150 }
151
152 module_init(ppc_md5_mod_init);
153 module_exit(ppc_md5_mod_fini);
154
155 MODULE_LICENSE("GPL");
156 MODULE_DESCRIPTION("MD5 Secure Hash Algorithm, PPC assembler");
157
158 MODULE_ALIAS_CRYPTO("md5");
159 MODULE_ALIAS_CRYPTO("md5-ppc");
160