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> 18 #include <crypto/internal/skcipher.h>
15 #include <linux/err.h> 19 #include <linux/err.h>
16 #include <linux/init.h> 20 #include <linux/init.h>
17 #include <linux/kernel.h> 21 #include <linux/kernel.h>
18 #include <linux/module.h> 22 #include <linux/module.h>
>> 23 #include <linux/slab.h>
>> 24 #include <linux/compiler.h>
>> 25
>> 26 struct crypto_pcbc_ctx {
>> 27 struct crypto_cipher *child;
>> 28 };
>> 29
>> 30 static int crypto_pcbc_setkey(struct crypto_skcipher *parent, const u8 *key,
>> 31 unsigned int keylen)
>> 32 {
>> 33 struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(parent);
>> 34 struct crypto_cipher *child = ctx->child;
>> 35 int err;
>> 36
>> 37 crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
>> 38 crypto_cipher_set_flags(child, crypto_skcipher_get_flags(parent) &
>> 39 CRYPTO_TFM_REQ_MASK);
>> 40 err = crypto_cipher_setkey(child, key, keylen);
>> 41 crypto_skcipher_set_flags(parent, crypto_cipher_get_flags(child) &
>> 42 CRYPTO_TFM_RES_MASK);
>> 43 return err;
>> 44 }
19 45
20 static int crypto_pcbc_encrypt_segment(struct 46 static int crypto_pcbc_encrypt_segment(struct skcipher_request *req,
21 struct 47 struct skcipher_walk *walk,
22 struct 48 struct crypto_cipher *tfm)
23 { 49 {
24 int bsize = crypto_cipher_blocksize(tf 50 int bsize = crypto_cipher_blocksize(tfm);
25 unsigned int nbytes = walk->nbytes; 51 unsigned int nbytes = walk->nbytes;
26 u8 *src = walk->src.virt.addr; 52 u8 *src = walk->src.virt.addr;
27 u8 *dst = walk->dst.virt.addr; 53 u8 *dst = walk->dst.virt.addr;
28 u8 * const iv = walk->iv; !! 54 u8 *iv = walk->iv;
29 55
30 do { 56 do {
31 crypto_xor(iv, src, bsize); 57 crypto_xor(iv, src, bsize);
32 crypto_cipher_encrypt_one(tfm, 58 crypto_cipher_encrypt_one(tfm, dst, iv);
33 crypto_xor_cpy(iv, dst, src, b 59 crypto_xor_cpy(iv, dst, src, bsize);
34 60
35 src += bsize; 61 src += bsize;
36 dst += bsize; 62 dst += bsize;
37 } while ((nbytes -= bsize) >= bsize); 63 } while ((nbytes -= bsize) >= bsize);
38 64
39 return nbytes; 65 return nbytes;
40 } 66 }
41 67
42 static int crypto_pcbc_encrypt_inplace(struct 68 static int crypto_pcbc_encrypt_inplace(struct skcipher_request *req,
43 struct 69 struct skcipher_walk *walk,
44 struct 70 struct crypto_cipher *tfm)
45 { 71 {
46 int bsize = crypto_cipher_blocksize(tf 72 int bsize = crypto_cipher_blocksize(tfm);
47 unsigned int nbytes = walk->nbytes; 73 unsigned int nbytes = walk->nbytes;
48 u8 *src = walk->src.virt.addr; 74 u8 *src = walk->src.virt.addr;
49 u8 * const iv = walk->iv; !! 75 u8 *iv = walk->iv;
50 u8 tmpbuf[MAX_CIPHER_BLOCKSIZE]; 76 u8 tmpbuf[MAX_CIPHER_BLOCKSIZE];
51 77
52 do { 78 do {
53 memcpy(tmpbuf, src, bsize); 79 memcpy(tmpbuf, src, bsize);
54 crypto_xor(iv, src, bsize); 80 crypto_xor(iv, src, bsize);
55 crypto_cipher_encrypt_one(tfm, 81 crypto_cipher_encrypt_one(tfm, src, iv);
56 crypto_xor_cpy(iv, tmpbuf, src 82 crypto_xor_cpy(iv, tmpbuf, src, bsize);
57 83
58 src += bsize; 84 src += bsize;
59 } while ((nbytes -= bsize) >= bsize); 85 } while ((nbytes -= bsize) >= bsize);
60 86
>> 87 memcpy(walk->iv, iv, bsize);
>> 88
61 return nbytes; 89 return nbytes;
62 } 90 }
63 91
64 static int crypto_pcbc_encrypt(struct skcipher 92 static int crypto_pcbc_encrypt(struct skcipher_request *req)
65 { 93 {
66 struct crypto_skcipher *tfm = crypto_s 94 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
67 struct crypto_cipher *cipher = skciphe !! 95 struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
>> 96 struct crypto_cipher *child = ctx->child;
68 struct skcipher_walk walk; 97 struct skcipher_walk walk;
69 unsigned int nbytes; 98 unsigned int nbytes;
70 int err; 99 int err;
71 100
72 err = skcipher_walk_virt(&walk, req, f 101 err = skcipher_walk_virt(&walk, req, false);
73 102
74 while (walk.nbytes) { !! 103 while ((nbytes = walk.nbytes)) {
75 if (walk.src.virt.addr == walk 104 if (walk.src.virt.addr == walk.dst.virt.addr)
76 nbytes = crypto_pcbc_e 105 nbytes = crypto_pcbc_encrypt_inplace(req, &walk,
77 !! 106 child);
78 else 107 else
79 nbytes = crypto_pcbc_e 108 nbytes = crypto_pcbc_encrypt_segment(req, &walk,
80 !! 109 child);
81 err = skcipher_walk_done(&walk 110 err = skcipher_walk_done(&walk, nbytes);
82 } 111 }
83 112
84 return err; 113 return err;
85 } 114 }
86 115
87 static int crypto_pcbc_decrypt_segment(struct 116 static int crypto_pcbc_decrypt_segment(struct skcipher_request *req,
88 struct 117 struct skcipher_walk *walk,
89 struct 118 struct crypto_cipher *tfm)
90 { 119 {
91 int bsize = crypto_cipher_blocksize(tf 120 int bsize = crypto_cipher_blocksize(tfm);
92 unsigned int nbytes = walk->nbytes; 121 unsigned int nbytes = walk->nbytes;
93 u8 *src = walk->src.virt.addr; 122 u8 *src = walk->src.virt.addr;
94 u8 *dst = walk->dst.virt.addr; 123 u8 *dst = walk->dst.virt.addr;
95 u8 * const iv = walk->iv; !! 124 u8 *iv = walk->iv;
96 125
97 do { 126 do {
98 crypto_cipher_decrypt_one(tfm, 127 crypto_cipher_decrypt_one(tfm, dst, src);
99 crypto_xor(dst, iv, bsize); 128 crypto_xor(dst, iv, bsize);
100 crypto_xor_cpy(iv, dst, src, b 129 crypto_xor_cpy(iv, dst, src, bsize);
101 130
102 src += bsize; 131 src += bsize;
103 dst += bsize; 132 dst += bsize;
104 } while ((nbytes -= bsize) >= bsize); 133 } while ((nbytes -= bsize) >= bsize);
105 134
>> 135 memcpy(walk->iv, iv, bsize);
>> 136
106 return nbytes; 137 return nbytes;
107 } 138 }
108 139
109 static int crypto_pcbc_decrypt_inplace(struct 140 static int crypto_pcbc_decrypt_inplace(struct skcipher_request *req,
110 struct 141 struct skcipher_walk *walk,
111 struct 142 struct crypto_cipher *tfm)
112 { 143 {
113 int bsize = crypto_cipher_blocksize(tf 144 int bsize = crypto_cipher_blocksize(tfm);
114 unsigned int nbytes = walk->nbytes; 145 unsigned int nbytes = walk->nbytes;
115 u8 *src = walk->src.virt.addr; 146 u8 *src = walk->src.virt.addr;
116 u8 * const iv = walk->iv; !! 147 u8 *iv = walk->iv;
117 u8 tmpbuf[MAX_CIPHER_BLOCKSIZE] __alig 148 u8 tmpbuf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(u32));
118 149
119 do { 150 do {
120 memcpy(tmpbuf, src, bsize); 151 memcpy(tmpbuf, src, bsize);
121 crypto_cipher_decrypt_one(tfm, 152 crypto_cipher_decrypt_one(tfm, src, src);
122 crypto_xor(src, iv, bsize); 153 crypto_xor(src, iv, bsize);
123 crypto_xor_cpy(iv, src, tmpbuf 154 crypto_xor_cpy(iv, src, tmpbuf, bsize);
124 155
125 src += bsize; 156 src += bsize;
126 } while ((nbytes -= bsize) >= bsize); 157 } while ((nbytes -= bsize) >= bsize);
127 158
>> 159 memcpy(walk->iv, iv, bsize);
>> 160
128 return nbytes; 161 return nbytes;
129 } 162 }
130 163
131 static int crypto_pcbc_decrypt(struct skcipher 164 static int crypto_pcbc_decrypt(struct skcipher_request *req)
132 { 165 {
133 struct crypto_skcipher *tfm = crypto_s 166 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
134 struct crypto_cipher *cipher = skciphe !! 167 struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
>> 168 struct crypto_cipher *child = ctx->child;
135 struct skcipher_walk walk; 169 struct skcipher_walk walk;
136 unsigned int nbytes; 170 unsigned int nbytes;
137 int err; 171 int err;
138 172
139 err = skcipher_walk_virt(&walk, req, f 173 err = skcipher_walk_virt(&walk, req, false);
140 174
141 while (walk.nbytes) { !! 175 while ((nbytes = walk.nbytes)) {
142 if (walk.src.virt.addr == walk 176 if (walk.src.virt.addr == walk.dst.virt.addr)
143 nbytes = crypto_pcbc_d 177 nbytes = crypto_pcbc_decrypt_inplace(req, &walk,
144 !! 178 child);
145 else 179 else
146 nbytes = crypto_pcbc_d 180 nbytes = crypto_pcbc_decrypt_segment(req, &walk,
147 !! 181 child);
148 err = skcipher_walk_done(&walk 182 err = skcipher_walk_done(&walk, nbytes);
149 } 183 }
150 184
151 return err; 185 return err;
152 } 186 }
153 187
>> 188 static int crypto_pcbc_init_tfm(struct crypto_skcipher *tfm)
>> 189 {
>> 190 struct skcipher_instance *inst = skcipher_alg_instance(tfm);
>> 191 struct crypto_spawn *spawn = skcipher_instance_ctx(inst);
>> 192 struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
>> 193 struct crypto_cipher *cipher;
>> 194
>> 195 cipher = crypto_spawn_cipher(spawn);
>> 196 if (IS_ERR(cipher))
>> 197 return PTR_ERR(cipher);
>> 198
>> 199 ctx->child = cipher;
>> 200 return 0;
>> 201 }
>> 202
>> 203 static void crypto_pcbc_exit_tfm(struct crypto_skcipher *tfm)
>> 204 {
>> 205 struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
>> 206
>> 207 crypto_free_cipher(ctx->child);
>> 208 }
>> 209
>> 210 static void crypto_pcbc_free(struct skcipher_instance *inst)
>> 211 {
>> 212 crypto_drop_skcipher(skcipher_instance_ctx(inst));
>> 213 kfree(inst);
>> 214 }
>> 215
154 static int crypto_pcbc_create(struct crypto_te 216 static int crypto_pcbc_create(struct crypto_template *tmpl, struct rtattr **tb)
155 { 217 {
156 struct skcipher_instance *inst; 218 struct skcipher_instance *inst;
>> 219 struct crypto_attr_type *algt;
>> 220 struct crypto_spawn *spawn;
>> 221 struct crypto_alg *alg;
157 int err; 222 int err;
158 223
159 inst = skcipher_alloc_instance_simple( !! 224 algt = crypto_get_attr_type(tb);
160 if (IS_ERR(inst)) !! 225 if (IS_ERR(algt))
161 return PTR_ERR(inst); !! 226 return PTR_ERR(algt);
>> 227
>> 228 if (((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) &
>> 229 ~CRYPTO_ALG_INTERNAL)
>> 230 return -EINVAL;
>> 231
>> 232 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
>> 233 if (!inst)
>> 234 return -ENOMEM;
>> 235
>> 236 alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER |
>> 237 (algt->type & CRYPTO_ALG_INTERNAL),
>> 238 CRYPTO_ALG_TYPE_MASK |
>> 239 (algt->mask & CRYPTO_ALG_INTERNAL));
>> 240 err = PTR_ERR(alg);
>> 241 if (IS_ERR(alg))
>> 242 goto err_free_inst;
>> 243
>> 244 spawn = skcipher_instance_ctx(inst);
>> 245 err = crypto_init_spawn(spawn, alg, skcipher_crypto_instance(inst),
>> 246 CRYPTO_ALG_TYPE_MASK);
>> 247 crypto_mod_put(alg);
>> 248 if (err)
>> 249 goto err_free_inst;
>> 250
>> 251 err = crypto_inst_setname(skcipher_crypto_instance(inst), "pcbc", alg);
>> 252 if (err)
>> 253 goto err_drop_spawn;
>> 254
>> 255 inst->alg.base.cra_flags = alg->cra_flags & CRYPTO_ALG_INTERNAL;
>> 256 inst->alg.base.cra_priority = alg->cra_priority;
>> 257 inst->alg.base.cra_blocksize = alg->cra_blocksize;
>> 258 inst->alg.base.cra_alignmask = alg->cra_alignmask;
>> 259
>> 260 inst->alg.ivsize = alg->cra_blocksize;
>> 261 inst->alg.min_keysize = alg->cra_cipher.cia_min_keysize;
>> 262 inst->alg.max_keysize = alg->cra_cipher.cia_max_keysize;
162 263
>> 264 inst->alg.base.cra_ctxsize = sizeof(struct crypto_pcbc_ctx);
>> 265
>> 266 inst->alg.init = crypto_pcbc_init_tfm;
>> 267 inst->alg.exit = crypto_pcbc_exit_tfm;
>> 268
>> 269 inst->alg.setkey = crypto_pcbc_setkey;
163 inst->alg.encrypt = crypto_pcbc_encryp 270 inst->alg.encrypt = crypto_pcbc_encrypt;
164 inst->alg.decrypt = crypto_pcbc_decryp 271 inst->alg.decrypt = crypto_pcbc_decrypt;
165 272
>> 273 inst->free = crypto_pcbc_free;
>> 274
166 err = skcipher_register_instance(tmpl, 275 err = skcipher_register_instance(tmpl, inst);
167 if (err) 276 if (err)
168 inst->free(inst); !! 277 goto err_drop_spawn;
169 278
>> 279 out:
170 return err; 280 return err;
>> 281
>> 282 err_drop_spawn:
>> 283 crypto_drop_spawn(spawn);
>> 284 err_free_inst:
>> 285 kfree(inst);
>> 286 goto out;
171 } 287 }
172 288
173 static struct crypto_template crypto_pcbc_tmpl 289 static struct crypto_template crypto_pcbc_tmpl = {
174 .name = "pcbc", 290 .name = "pcbc",
175 .create = crypto_pcbc_create, 291 .create = crypto_pcbc_create,
176 .module = THIS_MODULE, 292 .module = THIS_MODULE,
177 }; 293 };
178 294
179 static int __init crypto_pcbc_module_init(void 295 static int __init crypto_pcbc_module_init(void)
180 { 296 {
181 return crypto_register_template(&crypt 297 return crypto_register_template(&crypto_pcbc_tmpl);
182 } 298 }
183 299
184 static void __exit crypto_pcbc_module_exit(voi 300 static void __exit crypto_pcbc_module_exit(void)
185 { 301 {
186 crypto_unregister_template(&crypto_pcb 302 crypto_unregister_template(&crypto_pcbc_tmpl);
187 } 303 }
188 304
189 subsys_initcall(crypto_pcbc_module_init); !! 305 module_init(crypto_pcbc_module_init);
190 module_exit(crypto_pcbc_module_exit); 306 module_exit(crypto_pcbc_module_exit);
191 307
192 MODULE_LICENSE("GPL"); 308 MODULE_LICENSE("GPL");
193 MODULE_DESCRIPTION("PCBC block cipher mode of !! 309 MODULE_DESCRIPTION("PCBC block cipher algorithm");
194 MODULE_ALIAS_CRYPTO("pcbc"); 310 MODULE_ALIAS_CRYPTO("pcbc");
195 MODULE_IMPORT_NS(CRYPTO_INTERNAL); <<
196 311
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