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> <<
13 #include <crypto/internal/cipher.h> <<
14 #include <crypto/internal/skcipher.h> 17 #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/slab.h>
>> 23
>> 24 struct crypto_pcbc_ctx {
>> 25 struct crypto_cipher *child;
>> 26 };
>> 27
>> 28 static int crypto_pcbc_setkey(struct crypto_skcipher *parent, const u8 *key,
>> 29 unsigned int keylen)
>> 30 {
>> 31 struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(parent);
>> 32 struct crypto_cipher *child = ctx->child;
>> 33 int err;
>> 34
>> 35 crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
>> 36 crypto_cipher_set_flags(child, crypto_skcipher_get_flags(parent) &
>> 37 CRYPTO_TFM_REQ_MASK);
>> 38 err = crypto_cipher_setkey(child, key, keylen);
>> 39 crypto_skcipher_set_flags(parent, crypto_cipher_get_flags(child) &
>> 40 CRYPTO_TFM_RES_MASK);
>> 41 return err;
>> 42 }
19 43
20 static int crypto_pcbc_encrypt_segment(struct 44 static int crypto_pcbc_encrypt_segment(struct skcipher_request *req,
21 struct 45 struct skcipher_walk *walk,
22 struct 46 struct crypto_cipher *tfm)
23 { 47 {
24 int bsize = crypto_cipher_blocksize(tf 48 int bsize = crypto_cipher_blocksize(tfm);
25 unsigned int nbytes = walk->nbytes; 49 unsigned int nbytes = walk->nbytes;
26 u8 *src = walk->src.virt.addr; 50 u8 *src = walk->src.virt.addr;
27 u8 *dst = walk->dst.virt.addr; 51 u8 *dst = walk->dst.virt.addr;
28 u8 * const iv = walk->iv; !! 52 u8 *iv = walk->iv;
29 53
30 do { 54 do {
31 crypto_xor(iv, src, bsize); 55 crypto_xor(iv, src, bsize);
32 crypto_cipher_encrypt_one(tfm, 56 crypto_cipher_encrypt_one(tfm, dst, iv);
33 crypto_xor_cpy(iv, dst, src, b !! 57 memcpy(iv, dst, bsize);
>> 58 crypto_xor(iv, src, bsize);
34 59
35 src += bsize; 60 src += bsize;
36 dst += bsize; 61 dst += bsize;
37 } while ((nbytes -= bsize) >= bsize); 62 } while ((nbytes -= bsize) >= bsize);
38 63
39 return nbytes; 64 return nbytes;
40 } 65 }
41 66
42 static int crypto_pcbc_encrypt_inplace(struct 67 static int crypto_pcbc_encrypt_inplace(struct skcipher_request *req,
43 struct 68 struct skcipher_walk *walk,
44 struct 69 struct crypto_cipher *tfm)
45 { 70 {
46 int bsize = crypto_cipher_blocksize(tf 71 int bsize = crypto_cipher_blocksize(tfm);
47 unsigned int nbytes = walk->nbytes; 72 unsigned int nbytes = walk->nbytes;
48 u8 *src = walk->src.virt.addr; 73 u8 *src = walk->src.virt.addr;
49 u8 * const iv = walk->iv; !! 74 u8 *iv = walk->iv;
50 u8 tmpbuf[MAX_CIPHER_BLOCKSIZE]; !! 75 u8 tmpbuf[bsize];
51 76
52 do { 77 do {
53 memcpy(tmpbuf, src, bsize); 78 memcpy(tmpbuf, src, bsize);
54 crypto_xor(iv, src, bsize); 79 crypto_xor(iv, src, bsize);
55 crypto_cipher_encrypt_one(tfm, 80 crypto_cipher_encrypt_one(tfm, src, iv);
56 crypto_xor_cpy(iv, tmpbuf, src !! 81 memcpy(iv, tmpbuf, bsize);
>> 82 crypto_xor(iv, 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 memcpy(iv, src, bsize);
>> 130 crypto_xor(iv, dst, bsize);
101 131
102 src += bsize; 132 src += bsize;
103 dst += bsize; 133 dst += bsize;
104 } while ((nbytes -= bsize) >= bsize); 134 } while ((nbytes -= bsize) >= bsize);
105 135
>> 136 memcpy(walk->iv, iv, bsize);
>> 137
106 return nbytes; 138 return nbytes;
107 } 139 }
108 140
109 static int crypto_pcbc_decrypt_inplace(struct 141 static int crypto_pcbc_decrypt_inplace(struct skcipher_request *req,
110 struct 142 struct skcipher_walk *walk,
111 struct 143 struct crypto_cipher *tfm)
112 { 144 {
113 int bsize = crypto_cipher_blocksize(tf 145 int bsize = crypto_cipher_blocksize(tfm);
114 unsigned int nbytes = walk->nbytes; 146 unsigned int nbytes = walk->nbytes;
115 u8 *src = walk->src.virt.addr; 147 u8 *src = walk->src.virt.addr;
116 u8 * const iv = walk->iv; !! 148 u8 *iv = walk->iv;
117 u8 tmpbuf[MAX_CIPHER_BLOCKSIZE] __alig !! 149 u8 tmpbuf[bsize] __attribute__ ((aligned(__alignof__(u32))));
118 150
119 do { 151 do {
120 memcpy(tmpbuf, src, bsize); 152 memcpy(tmpbuf, src, bsize);
121 crypto_cipher_decrypt_one(tfm, 153 crypto_cipher_decrypt_one(tfm, src, src);
122 crypto_xor(src, iv, bsize); 154 crypto_xor(src, iv, bsize);
123 crypto_xor_cpy(iv, src, tmpbuf !! 155 memcpy(iv, tmpbuf, bsize);
>> 156 crypto_xor(iv, src, bsize);
124 157
125 src += bsize; 158 src += bsize;
126 } while ((nbytes -= bsize) >= bsize); 159 } while ((nbytes -= bsize) >= bsize);
127 160
>> 161 memcpy(walk->iv, iv, bsize);
>> 162
128 return nbytes; 163 return nbytes;
129 } 164 }
130 165
131 static int crypto_pcbc_decrypt(struct skcipher 166 static int crypto_pcbc_decrypt(struct skcipher_request *req)
132 { 167 {
133 struct crypto_skcipher *tfm = crypto_s 168 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
134 struct crypto_cipher *cipher = skciphe !! 169 struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
>> 170 struct crypto_cipher *child = ctx->child;
135 struct skcipher_walk walk; 171 struct skcipher_walk walk;
136 unsigned int nbytes; 172 unsigned int nbytes;
137 int err; 173 int err;
138 174
139 err = skcipher_walk_virt(&walk, req, f 175 err = skcipher_walk_virt(&walk, req, false);
140 176
141 while (walk.nbytes) { !! 177 while ((nbytes = walk.nbytes)) {
142 if (walk.src.virt.addr == walk 178 if (walk.src.virt.addr == walk.dst.virt.addr)
143 nbytes = crypto_pcbc_d 179 nbytes = crypto_pcbc_decrypt_inplace(req, &walk,
144 !! 180 child);
145 else 181 else
146 nbytes = crypto_pcbc_d 182 nbytes = crypto_pcbc_decrypt_segment(req, &walk,
147 !! 183 child);
148 err = skcipher_walk_done(&walk 184 err = skcipher_walk_done(&walk, nbytes);
149 } 185 }
150 186
151 return err; 187 return err;
152 } 188 }
153 189
>> 190 static int crypto_pcbc_init_tfm(struct crypto_skcipher *tfm)
>> 191 {
>> 192 struct skcipher_instance *inst = skcipher_alg_instance(tfm);
>> 193 struct crypto_spawn *spawn = skcipher_instance_ctx(inst);
>> 194 struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
>> 195 struct crypto_cipher *cipher;
>> 196
>> 197 cipher = crypto_spawn_cipher(spawn);
>> 198 if (IS_ERR(cipher))
>> 199 return PTR_ERR(cipher);
>> 200
>> 201 ctx->child = cipher;
>> 202 return 0;
>> 203 }
>> 204
>> 205 static void crypto_pcbc_exit_tfm(struct crypto_skcipher *tfm)
>> 206 {
>> 207 struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm);
>> 208
>> 209 crypto_free_cipher(ctx->child);
>> 210 }
>> 211
>> 212 static void crypto_pcbc_free(struct skcipher_instance *inst)
>> 213 {
>> 214 crypto_drop_skcipher(skcipher_instance_ctx(inst));
>> 215 kfree(inst);
>> 216 }
>> 217
154 static int crypto_pcbc_create(struct crypto_te 218 static int crypto_pcbc_create(struct crypto_template *tmpl, struct rtattr **tb)
155 { 219 {
156 struct skcipher_instance *inst; 220 struct skcipher_instance *inst;
>> 221 struct crypto_attr_type *algt;
>> 222 struct crypto_spawn *spawn;
>> 223 struct crypto_alg *alg;
157 int err; 224 int err;
158 225
159 inst = skcipher_alloc_instance_simple( !! 226 algt = crypto_get_attr_type(tb);
160 if (IS_ERR(inst)) !! 227 if (IS_ERR(algt))
161 return PTR_ERR(inst); !! 228 return PTR_ERR(algt);
>> 229
>> 230 if (((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) &
>> 231 ~CRYPTO_ALG_INTERNAL)
>> 232 return -EINVAL;
>> 233
>> 234 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
>> 235 if (!inst)
>> 236 return -ENOMEM;
>> 237
>> 238 alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER |
>> 239 (algt->type & CRYPTO_ALG_INTERNAL),
>> 240 CRYPTO_ALG_TYPE_MASK |
>> 241 (algt->mask & CRYPTO_ALG_INTERNAL));
>> 242 err = PTR_ERR(alg);
>> 243 if (IS_ERR(alg))
>> 244 goto err_free_inst;
>> 245
>> 246 spawn = skcipher_instance_ctx(inst);
>> 247 err = crypto_init_spawn(spawn, alg, skcipher_crypto_instance(inst),
>> 248 CRYPTO_ALG_TYPE_MASK);
>> 249 crypto_mod_put(alg);
>> 250 if (err)
>> 251 goto err_free_inst;
>> 252
>> 253 err = crypto_inst_setname(skcipher_crypto_instance(inst), "pcbc", alg);
>> 254 if (err)
>> 255 goto err_drop_spawn;
>> 256
>> 257 inst->alg.base.cra_flags = alg->cra_flags & CRYPTO_ALG_INTERNAL;
>> 258 inst->alg.base.cra_priority = alg->cra_priority;
>> 259 inst->alg.base.cra_blocksize = alg->cra_blocksize;
>> 260 inst->alg.base.cra_alignmask = alg->cra_alignmask;
>> 261
>> 262 /* We access the data as u32s when xoring. */
>> 263 inst->alg.base.cra_alignmask |= __alignof__(u32) - 1;
>> 264
>> 265 inst->alg.ivsize = alg->cra_blocksize;
>> 266 inst->alg.min_keysize = alg->cra_cipher.cia_min_keysize;
>> 267 inst->alg.max_keysize = alg->cra_cipher.cia_max_keysize;
162 268
>> 269 inst->alg.base.cra_ctxsize = sizeof(struct crypto_pcbc_ctx);
>> 270
>> 271 inst->alg.init = crypto_pcbc_init_tfm;
>> 272 inst->alg.exit = crypto_pcbc_exit_tfm;
>> 273
>> 274 inst->alg.setkey = crypto_pcbc_setkey;
163 inst->alg.encrypt = crypto_pcbc_encryp 275 inst->alg.encrypt = crypto_pcbc_encrypt;
164 inst->alg.decrypt = crypto_pcbc_decryp 276 inst->alg.decrypt = crypto_pcbc_decrypt;
165 277
>> 278 inst->free = crypto_pcbc_free;
>> 279
166 err = skcipher_register_instance(tmpl, 280 err = skcipher_register_instance(tmpl, inst);
167 if (err) 281 if (err)
168 inst->free(inst); !! 282 goto err_drop_spawn;
169 283
>> 284 out:
170 return err; 285 return err;
>> 286
>> 287 err_drop_spawn:
>> 288 crypto_drop_spawn(spawn);
>> 289 err_free_inst:
>> 290 kfree(inst);
>> 291 goto out;
171 } 292 }
172 293
173 static struct crypto_template crypto_pcbc_tmpl 294 static struct crypto_template crypto_pcbc_tmpl = {
174 .name = "pcbc", 295 .name = "pcbc",
175 .create = crypto_pcbc_create, 296 .create = crypto_pcbc_create,
176 .module = THIS_MODULE, 297 .module = THIS_MODULE,
177 }; 298 };
178 299
179 static int __init crypto_pcbc_module_init(void 300 static int __init crypto_pcbc_module_init(void)
180 { 301 {
181 return crypto_register_template(&crypt 302 return crypto_register_template(&crypto_pcbc_tmpl);
182 } 303 }
183 304
184 static void __exit crypto_pcbc_module_exit(voi 305 static void __exit crypto_pcbc_module_exit(void)
185 { 306 {
186 crypto_unregister_template(&crypto_pcb 307 crypto_unregister_template(&crypto_pcbc_tmpl);
187 } 308 }
188 309
189 subsys_initcall(crypto_pcbc_module_init); !! 310 module_init(crypto_pcbc_module_init);
190 module_exit(crypto_pcbc_module_exit); 311 module_exit(crypto_pcbc_module_exit);
191 312
192 MODULE_LICENSE("GPL"); 313 MODULE_LICENSE("GPL");
193 MODULE_DESCRIPTION("PCBC block cipher mode of !! 314 MODULE_DESCRIPTION("PCBC block cipher algorithm");
194 MODULE_ALIAS_CRYPTO("pcbc"); 315 MODULE_ALIAS_CRYPTO("pcbc");
195 MODULE_IMPORT_NS(CRYPTO_INTERNAL); <<
196 316
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