1 // SPDX-License-Identifier: GPL-2.0-or-later <<
2 /* 1 /*
3 * PCBC: Propagating Cipher Block Chaining mod 2 * PCBC: Propagating Cipher Block Chaining mode
4 * 3 *
5 * Copyright (C) 2006 Red Hat, Inc. All Rights 4 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
6 * Written by David Howells (dhowells@redhat.c 5 * Written by David Howells (dhowells@redhat.com)
7 * 6 *
8 * Derived from cbc.c 7 * Derived from cbc.c
9 * - Copyright (c) 2006 Herbert Xu <herbert@go 8 * - Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
>> 9 *
>> 10 * This program is free software; you can redistribute it and/or modify it
>> 11 * under the terms of the GNU General Public License as published by the Free
>> 12 * Software Foundation; either version 2 of the License, or (at your option)
>> 13 * any later version.
>> 14 *
10 */ 15 */
11 16
12 #include <crypto/algapi.h> 17 #include <crypto/algapi.h>
13 #include <crypto/internal/cipher.h> <<
14 #include <crypto/internal/skcipher.h> <<
15 #include <linux/err.h> 18 #include <linux/err.h>
16 #include <linux/init.h> 19 #include <linux/init.h>
17 #include <linux/kernel.h> 20 #include <linux/kernel.h>
18 #include <linux/module.h> 21 #include <linux/module.h>
>> 22 #include <linux/scatterlist.h>
>> 23 #include <linux/slab.h>
>> 24
>> 25 struct crypto_pcbc_ctx {
>> 26 struct crypto_cipher *child;
>> 27 };
>> 28
>> 29 static int crypto_pcbc_setkey(struct crypto_tfm *parent, const u8 *key,
>> 30 unsigned int keylen)
>> 31 {
>> 32 struct crypto_pcbc_ctx *ctx = crypto_tfm_ctx(parent);
>> 33 struct crypto_cipher *child = ctx->child;
>> 34 int err;
>> 35
>> 36 crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
>> 37 crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) &
>> 38 CRYPTO_TFM_REQ_MASK);
>> 39 err = crypto_cipher_setkey(child, key, keylen);
>> 40 crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) &
>> 41 CRYPTO_TFM_RES_MASK);
>> 42 return err;
>> 43 }
19 44
20 static int crypto_pcbc_encrypt_segment(struct !! 45 static int crypto_pcbc_encrypt_segment(struct blkcipher_desc *desc,
21 struct !! 46 struct blkcipher_walk *walk,
22 struct 47 struct crypto_cipher *tfm)
23 { 48 {
>> 49 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
>> 50 crypto_cipher_alg(tfm)->cia_encrypt;
24 int bsize = crypto_cipher_blocksize(tf 51 int bsize = crypto_cipher_blocksize(tfm);
25 unsigned int nbytes = walk->nbytes; 52 unsigned int nbytes = walk->nbytes;
26 u8 *src = walk->src.virt.addr; 53 u8 *src = walk->src.virt.addr;
27 u8 *dst = walk->dst.virt.addr; 54 u8 *dst = walk->dst.virt.addr;
28 u8 * const iv = walk->iv; !! 55 u8 *iv = walk->iv;
29 56
30 do { 57 do {
31 crypto_xor(iv, src, bsize); 58 crypto_xor(iv, src, bsize);
32 crypto_cipher_encrypt_one(tfm, !! 59 fn(crypto_cipher_tfm(tfm), dst, iv);
33 crypto_xor_cpy(iv, dst, src, b !! 60 memcpy(iv, dst, bsize);
>> 61 crypto_xor(iv, src, bsize);
34 62
35 src += bsize; 63 src += bsize;
36 dst += bsize; 64 dst += bsize;
37 } while ((nbytes -= bsize) >= bsize); 65 } while ((nbytes -= bsize) >= bsize);
38 66
39 return nbytes; 67 return nbytes;
40 } 68 }
41 69
42 static int crypto_pcbc_encrypt_inplace(struct !! 70 static int crypto_pcbc_encrypt_inplace(struct blkcipher_desc *desc,
43 struct !! 71 struct blkcipher_walk *walk,
44 struct 72 struct crypto_cipher *tfm)
45 { 73 {
>> 74 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
>> 75 crypto_cipher_alg(tfm)->cia_encrypt;
46 int bsize = crypto_cipher_blocksize(tf 76 int bsize = crypto_cipher_blocksize(tfm);
47 unsigned int nbytes = walk->nbytes; 77 unsigned int nbytes = walk->nbytes;
48 u8 *src = walk->src.virt.addr; 78 u8 *src = walk->src.virt.addr;
49 u8 * const iv = walk->iv; !! 79 u8 *iv = walk->iv;
50 u8 tmpbuf[MAX_CIPHER_BLOCKSIZE]; !! 80 u8 tmpbuf[bsize];
51 81
52 do { 82 do {
53 memcpy(tmpbuf, src, bsize); 83 memcpy(tmpbuf, src, bsize);
54 crypto_xor(iv, src, bsize); 84 crypto_xor(iv, src, bsize);
55 crypto_cipher_encrypt_one(tfm, !! 85 fn(crypto_cipher_tfm(tfm), src, iv);
56 crypto_xor_cpy(iv, tmpbuf, src !! 86 memcpy(iv, tmpbuf, bsize);
>> 87 crypto_xor(iv, src, bsize);
57 88
58 src += bsize; 89 src += bsize;
59 } while ((nbytes -= bsize) >= bsize); 90 } while ((nbytes -= bsize) >= bsize);
60 91
>> 92 memcpy(walk->iv, iv, bsize);
>> 93
61 return nbytes; 94 return nbytes;
62 } 95 }
63 96
64 static int crypto_pcbc_encrypt(struct skcipher !! 97 static int crypto_pcbc_encrypt(struct blkcipher_desc *desc,
>> 98 struct scatterlist *dst, struct scatterlist *src,
>> 99 unsigned int nbytes)
65 { 100 {
66 struct crypto_skcipher *tfm = crypto_s !! 101 struct blkcipher_walk walk;
67 struct crypto_cipher *cipher = skciphe !! 102 struct crypto_blkcipher *tfm = desc->tfm;
68 struct skcipher_walk walk; !! 103 struct crypto_pcbc_ctx *ctx = crypto_blkcipher_ctx(tfm);
69 unsigned int nbytes; !! 104 struct crypto_cipher *child = ctx->child;
70 int err; 105 int err;
71 106
72 err = skcipher_walk_virt(&walk, req, f !! 107 blkcipher_walk_init(&walk, dst, src, nbytes);
>> 108 err = blkcipher_walk_virt(desc, &walk);
73 109
74 while (walk.nbytes) { !! 110 while ((nbytes = walk.nbytes)) {
75 if (walk.src.virt.addr == walk 111 if (walk.src.virt.addr == walk.dst.virt.addr)
76 nbytes = crypto_pcbc_e !! 112 nbytes = crypto_pcbc_encrypt_inplace(desc, &walk,
77 !! 113 child);
78 else 114 else
79 nbytes = crypto_pcbc_e !! 115 nbytes = crypto_pcbc_encrypt_segment(desc, &walk,
80 !! 116 child);
81 err = skcipher_walk_done(&walk !! 117 err = blkcipher_walk_done(desc, &walk, nbytes);
82 } 118 }
83 119
84 return err; 120 return err;
85 } 121 }
86 122
87 static int crypto_pcbc_decrypt_segment(struct !! 123 static int crypto_pcbc_decrypt_segment(struct blkcipher_desc *desc,
88 struct !! 124 struct blkcipher_walk *walk,
89 struct 125 struct crypto_cipher *tfm)
90 { 126 {
>> 127 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
>> 128 crypto_cipher_alg(tfm)->cia_decrypt;
91 int bsize = crypto_cipher_blocksize(tf 129 int bsize = crypto_cipher_blocksize(tfm);
92 unsigned int nbytes = walk->nbytes; 130 unsigned int nbytes = walk->nbytes;
93 u8 *src = walk->src.virt.addr; 131 u8 *src = walk->src.virt.addr;
94 u8 *dst = walk->dst.virt.addr; 132 u8 *dst = walk->dst.virt.addr;
95 u8 * const iv = walk->iv; !! 133 u8 *iv = walk->iv;
96 134
97 do { 135 do {
98 crypto_cipher_decrypt_one(tfm, !! 136 fn(crypto_cipher_tfm(tfm), dst, src);
99 crypto_xor(dst, iv, bsize); 137 crypto_xor(dst, iv, bsize);
100 crypto_xor_cpy(iv, dst, src, b !! 138 memcpy(iv, src, bsize);
>> 139 crypto_xor(iv, dst, bsize);
101 140
102 src += bsize; 141 src += bsize;
103 dst += bsize; 142 dst += bsize;
104 } while ((nbytes -= bsize) >= bsize); 143 } while ((nbytes -= bsize) >= bsize);
105 144
>> 145 memcpy(walk->iv, iv, bsize);
>> 146
106 return nbytes; 147 return nbytes;
107 } 148 }
108 149
109 static int crypto_pcbc_decrypt_inplace(struct !! 150 static int crypto_pcbc_decrypt_inplace(struct blkcipher_desc *desc,
110 struct !! 151 struct blkcipher_walk *walk,
111 struct 152 struct crypto_cipher *tfm)
112 { 153 {
>> 154 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
>> 155 crypto_cipher_alg(tfm)->cia_decrypt;
113 int bsize = crypto_cipher_blocksize(tf 156 int bsize = crypto_cipher_blocksize(tfm);
114 unsigned int nbytes = walk->nbytes; 157 unsigned int nbytes = walk->nbytes;
115 u8 *src = walk->src.virt.addr; 158 u8 *src = walk->src.virt.addr;
116 u8 * const iv = walk->iv; !! 159 u8 *iv = walk->iv;
117 u8 tmpbuf[MAX_CIPHER_BLOCKSIZE] __alig !! 160 u8 tmpbuf[bsize];
118 161
119 do { 162 do {
120 memcpy(tmpbuf, src, bsize); 163 memcpy(tmpbuf, src, bsize);
121 crypto_cipher_decrypt_one(tfm, !! 164 fn(crypto_cipher_tfm(tfm), src, src);
122 crypto_xor(src, iv, bsize); 165 crypto_xor(src, iv, bsize);
123 crypto_xor_cpy(iv, src, tmpbuf !! 166 memcpy(iv, tmpbuf, bsize);
>> 167 crypto_xor(iv, src, bsize);
124 168
125 src += bsize; 169 src += bsize;
126 } while ((nbytes -= bsize) >= bsize); 170 } while ((nbytes -= bsize) >= bsize);
127 171
>> 172 memcpy(walk->iv, iv, bsize);
>> 173
128 return nbytes; 174 return nbytes;
129 } 175 }
130 176
131 static int crypto_pcbc_decrypt(struct skcipher !! 177 static int crypto_pcbc_decrypt(struct blkcipher_desc *desc,
>> 178 struct scatterlist *dst, struct scatterlist *src,
>> 179 unsigned int nbytes)
132 { 180 {
133 struct crypto_skcipher *tfm = crypto_s !! 181 struct blkcipher_walk walk;
134 struct crypto_cipher *cipher = skciphe !! 182 struct crypto_blkcipher *tfm = desc->tfm;
135 struct skcipher_walk walk; !! 183 struct crypto_pcbc_ctx *ctx = crypto_blkcipher_ctx(tfm);
136 unsigned int nbytes; !! 184 struct crypto_cipher *child = ctx->child;
137 int err; 185 int err;
138 186
139 err = skcipher_walk_virt(&walk, req, f !! 187 blkcipher_walk_init(&walk, dst, src, nbytes);
>> 188 err = blkcipher_walk_virt(desc, &walk);
140 189
141 while (walk.nbytes) { !! 190 while ((nbytes = walk.nbytes)) {
142 if (walk.src.virt.addr == walk 191 if (walk.src.virt.addr == walk.dst.virt.addr)
143 nbytes = crypto_pcbc_d !! 192 nbytes = crypto_pcbc_decrypt_inplace(desc, &walk,
144 !! 193 child);
145 else 194 else
146 nbytes = crypto_pcbc_d !! 195 nbytes = crypto_pcbc_decrypt_segment(desc, &walk,
147 !! 196 child);
148 err = skcipher_walk_done(&walk !! 197 err = blkcipher_walk_done(desc, &walk, nbytes);
149 } 198 }
150 199
151 return err; 200 return err;
152 } 201 }
153 202
154 static int crypto_pcbc_create(struct crypto_te !! 203 static int crypto_pcbc_init_tfm(struct crypto_tfm *tfm)
155 { 204 {
156 struct skcipher_instance *inst; !! 205 struct crypto_instance *inst = (void *)tfm->__crt_alg;
>> 206 struct crypto_spawn *spawn = crypto_instance_ctx(inst);
>> 207 struct crypto_pcbc_ctx *ctx = crypto_tfm_ctx(tfm);
>> 208 struct crypto_cipher *cipher;
>> 209
>> 210 cipher = crypto_spawn_cipher(spawn);
>> 211 if (IS_ERR(cipher))
>> 212 return PTR_ERR(cipher);
>> 213
>> 214 ctx->child = cipher;
>> 215 return 0;
>> 216 }
>> 217
>> 218 static void crypto_pcbc_exit_tfm(struct crypto_tfm *tfm)
>> 219 {
>> 220 struct crypto_pcbc_ctx *ctx = crypto_tfm_ctx(tfm);
>> 221 crypto_free_cipher(ctx->child);
>> 222 }
>> 223
>> 224 static struct crypto_instance *crypto_pcbc_alloc(struct rtattr **tb)
>> 225 {
>> 226 struct crypto_instance *inst;
>> 227 struct crypto_alg *alg;
157 int err; 228 int err;
158 229
159 inst = skcipher_alloc_instance_simple( !! 230 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER);
>> 231 if (err)
>> 232 return ERR_PTR(err);
>> 233
>> 234 alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
>> 235 CRYPTO_ALG_TYPE_MASK);
>> 236 if (IS_ERR(alg))
>> 237 return ERR_CAST(alg);
>> 238
>> 239 inst = crypto_alloc_instance("pcbc", alg);
160 if (IS_ERR(inst)) 240 if (IS_ERR(inst))
161 return PTR_ERR(inst); !! 241 goto out_put_alg;
162 242
163 inst->alg.encrypt = crypto_pcbc_encryp !! 243 inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
164 inst->alg.decrypt = crypto_pcbc_decryp !! 244 inst->alg.cra_priority = alg->cra_priority;
>> 245 inst->alg.cra_blocksize = alg->cra_blocksize;
>> 246 inst->alg.cra_alignmask = alg->cra_alignmask;
>> 247 inst->alg.cra_type = &crypto_blkcipher_type;
165 248
166 err = skcipher_register_instance(tmpl, !! 249 /* We access the data as u32s when xoring. */
167 if (err) !! 250 inst->alg.cra_alignmask |= __alignof__(u32) - 1;
168 inst->free(inst); <<
169 251
170 return err; !! 252 inst->alg.cra_blkcipher.ivsize = alg->cra_blocksize;
>> 253 inst->alg.cra_blkcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
>> 254 inst->alg.cra_blkcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
>> 255
>> 256 inst->alg.cra_ctxsize = sizeof(struct crypto_pcbc_ctx);
>> 257
>> 258 inst->alg.cra_init = crypto_pcbc_init_tfm;
>> 259 inst->alg.cra_exit = crypto_pcbc_exit_tfm;
>> 260
>> 261 inst->alg.cra_blkcipher.setkey = crypto_pcbc_setkey;
>> 262 inst->alg.cra_blkcipher.encrypt = crypto_pcbc_encrypt;
>> 263 inst->alg.cra_blkcipher.decrypt = crypto_pcbc_decrypt;
>> 264
>> 265 out_put_alg:
>> 266 crypto_mod_put(alg);
>> 267 return inst;
>> 268 }
>> 269
>> 270 static void crypto_pcbc_free(struct crypto_instance *inst)
>> 271 {
>> 272 crypto_drop_spawn(crypto_instance_ctx(inst));
>> 273 kfree(inst);
171 } 274 }
172 275
173 static struct crypto_template crypto_pcbc_tmpl 276 static struct crypto_template crypto_pcbc_tmpl = {
174 .name = "pcbc", 277 .name = "pcbc",
175 .create = crypto_pcbc_create, !! 278 .alloc = crypto_pcbc_alloc,
>> 279 .free = crypto_pcbc_free,
176 .module = THIS_MODULE, 280 .module = THIS_MODULE,
177 }; 281 };
178 282
179 static int __init crypto_pcbc_module_init(void 283 static int __init crypto_pcbc_module_init(void)
180 { 284 {
181 return crypto_register_template(&crypt 285 return crypto_register_template(&crypto_pcbc_tmpl);
182 } 286 }
183 287
184 static void __exit crypto_pcbc_module_exit(voi 288 static void __exit crypto_pcbc_module_exit(void)
185 { 289 {
186 crypto_unregister_template(&crypto_pcb 290 crypto_unregister_template(&crypto_pcbc_tmpl);
187 } 291 }
188 292
189 subsys_initcall(crypto_pcbc_module_init); !! 293 module_init(crypto_pcbc_module_init);
190 module_exit(crypto_pcbc_module_exit); 294 module_exit(crypto_pcbc_module_exit);
191 295
192 MODULE_LICENSE("GPL"); 296 MODULE_LICENSE("GPL");
193 MODULE_DESCRIPTION("PCBC block cipher mode of !! 297 MODULE_DESCRIPTION("PCBC block cipher algorithm");
194 MODULE_ALIAS_CRYPTO("pcbc"); 298 MODULE_ALIAS_CRYPTO("pcbc");
195 MODULE_IMPORT_NS(CRYPTO_INTERNAL); <<
196 299
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