Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 1 | /* |
| 2 | * CTR: Counter mode |
| 3 | * |
| 4 | * (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License as published by the Free |
| 8 | * Software Foundation; either version 2 of the License, or (at your option) |
| 9 | * any later version. |
| 10 | * |
| 11 | */ |
| 12 | |
| 13 | #include <crypto/algapi.h> |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 14 | #include <crypto/ctr.h> |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 15 | #include <crypto/internal/skcipher.h> |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 16 | #include <linux/err.h> |
| 17 | #include <linux/init.h> |
| 18 | #include <linux/kernel.h> |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/random.h> |
| 21 | #include <linux/scatterlist.h> |
| 22 | #include <linux/slab.h> |
| 23 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 24 | struct crypto_ctr_ctx { |
| 25 | struct crypto_cipher *child; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 26 | }; |
| 27 | |
| 28 | struct crypto_rfc3686_ctx { |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 29 | struct crypto_ablkcipher *child; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 30 | u8 nonce[CTR_RFC3686_NONCE_SIZE]; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 31 | }; |
| 32 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 33 | struct crypto_rfc3686_req_ctx { |
| 34 | u8 iv[CTR_RFC3686_BLOCK_SIZE]; |
| 35 | struct ablkcipher_request subreq CRYPTO_MINALIGN_ATTR; |
| 36 | }; |
| 37 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 38 | static int crypto_ctr_setkey(struct crypto_tfm *parent, const u8 *key, |
| 39 | unsigned int keylen) |
| 40 | { |
| 41 | struct crypto_ctr_ctx *ctx = crypto_tfm_ctx(parent); |
| 42 | struct crypto_cipher *child = ctx->child; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 43 | int err; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 44 | |
| 45 | crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); |
| 46 | crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) & |
| 47 | CRYPTO_TFM_REQ_MASK); |
| 48 | err = crypto_cipher_setkey(child, key, keylen); |
| 49 | crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) & |
| 50 | CRYPTO_TFM_RES_MASK); |
| 51 | |
| 52 | return err; |
| 53 | } |
| 54 | |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 55 | static void crypto_ctr_crypt_final(struct blkcipher_walk *walk, |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 56 | struct crypto_cipher *tfm) |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 57 | { |
| 58 | unsigned int bsize = crypto_cipher_blocksize(tfm); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 59 | unsigned long alignmask = crypto_cipher_alignmask(tfm); |
| 60 | u8 *ctrblk = walk->iv; |
| 61 | u8 tmp[bsize + alignmask]; |
| 62 | u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1); |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 63 | u8 *src = walk->src.virt.addr; |
| 64 | u8 *dst = walk->dst.virt.addr; |
| 65 | unsigned int nbytes = walk->nbytes; |
| 66 | |
| 67 | crypto_cipher_encrypt_one(tfm, keystream, ctrblk); |
| 68 | crypto_xor(keystream, src, nbytes); |
| 69 | memcpy(dst, keystream, nbytes); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 70 | |
| 71 | crypto_inc(ctrblk, bsize); |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 72 | } |
| 73 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 74 | static int crypto_ctr_crypt_segment(struct blkcipher_walk *walk, |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 75 | struct crypto_cipher *tfm) |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 76 | { |
| 77 | void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = |
| 78 | crypto_cipher_alg(tfm)->cia_encrypt; |
| 79 | unsigned int bsize = crypto_cipher_blocksize(tfm); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 80 | u8 *ctrblk = walk->iv; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 81 | u8 *src = walk->src.virt.addr; |
| 82 | u8 *dst = walk->dst.virt.addr; |
| 83 | unsigned int nbytes = walk->nbytes; |
| 84 | |
| 85 | do { |
| 86 | /* create keystream */ |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 87 | fn(crypto_cipher_tfm(tfm), dst, ctrblk); |
| 88 | crypto_xor(dst, src, bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 89 | |
| 90 | /* increment counter in counterblock */ |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 91 | crypto_inc(ctrblk, bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 92 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 93 | src += bsize; |
| 94 | dst += bsize; |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 95 | } while ((nbytes -= bsize) >= bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 96 | |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 97 | return nbytes; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 98 | } |
| 99 | |
| 100 | static int crypto_ctr_crypt_inplace(struct blkcipher_walk *walk, |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 101 | struct crypto_cipher *tfm) |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 102 | { |
| 103 | void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = |
| 104 | crypto_cipher_alg(tfm)->cia_encrypt; |
| 105 | unsigned int bsize = crypto_cipher_blocksize(tfm); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 106 | unsigned long alignmask = crypto_cipher_alignmask(tfm); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 107 | unsigned int nbytes = walk->nbytes; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 108 | u8 *ctrblk = walk->iv; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 109 | u8 *src = walk->src.virt.addr; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 110 | u8 tmp[bsize + alignmask]; |
| 111 | u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 112 | |
| 113 | do { |
| 114 | /* create keystream */ |
| 115 | fn(crypto_cipher_tfm(tfm), keystream, ctrblk); |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 116 | crypto_xor(src, keystream, bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 117 | |
| 118 | /* increment counter in counterblock */ |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 119 | crypto_inc(ctrblk, bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 120 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 121 | src += bsize; |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 122 | } while ((nbytes -= bsize) >= bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 123 | |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 124 | return nbytes; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 125 | } |
| 126 | |
| 127 | static int crypto_ctr_crypt(struct blkcipher_desc *desc, |
| 128 | struct scatterlist *dst, struct scatterlist *src, |
| 129 | unsigned int nbytes) |
| 130 | { |
| 131 | struct blkcipher_walk walk; |
| 132 | struct crypto_blkcipher *tfm = desc->tfm; |
| 133 | struct crypto_ctr_ctx *ctx = crypto_blkcipher_ctx(tfm); |
| 134 | struct crypto_cipher *child = ctx->child; |
| 135 | unsigned int bsize = crypto_cipher_blocksize(child); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 136 | int err; |
| 137 | |
| 138 | blkcipher_walk_init(&walk, dst, src, nbytes); |
| 139 | err = blkcipher_walk_virt_block(desc, &walk, bsize); |
| 140 | |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 141 | while (walk.nbytes >= bsize) { |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 142 | if (walk.src.virt.addr == walk.dst.virt.addr) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 143 | nbytes = crypto_ctr_crypt_inplace(&walk, child); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 144 | else |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 145 | nbytes = crypto_ctr_crypt_segment(&walk, child); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 146 | |
| 147 | err = blkcipher_walk_done(desc, &walk, nbytes); |
| 148 | } |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 149 | |
| 150 | if (walk.nbytes) { |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 151 | crypto_ctr_crypt_final(&walk, child); |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 152 | err = blkcipher_walk_done(desc, &walk, 0); |
| 153 | } |
| 154 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 155 | return err; |
| 156 | } |
| 157 | |
| 158 | static int crypto_ctr_init_tfm(struct crypto_tfm *tfm) |
| 159 | { |
| 160 | struct crypto_instance *inst = (void *)tfm->__crt_alg; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 161 | struct crypto_spawn *spawn = crypto_instance_ctx(inst); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 162 | struct crypto_ctr_ctx *ctx = crypto_tfm_ctx(tfm); |
| 163 | struct crypto_cipher *cipher; |
| 164 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 165 | cipher = crypto_spawn_cipher(spawn); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 166 | if (IS_ERR(cipher)) |
| 167 | return PTR_ERR(cipher); |
| 168 | |
| 169 | ctx->child = cipher; |
| 170 | |
| 171 | return 0; |
| 172 | } |
| 173 | |
| 174 | static void crypto_ctr_exit_tfm(struct crypto_tfm *tfm) |
| 175 | { |
| 176 | struct crypto_ctr_ctx *ctx = crypto_tfm_ctx(tfm); |
| 177 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 178 | crypto_free_cipher(ctx->child); |
| 179 | } |
| 180 | |
| 181 | static struct crypto_instance *crypto_ctr_alloc(struct rtattr **tb) |
| 182 | { |
| 183 | struct crypto_instance *inst; |
| 184 | struct crypto_alg *alg; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 185 | int err; |
| 186 | |
| 187 | err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER); |
| 188 | if (err) |
| 189 | return ERR_PTR(err); |
| 190 | |
| 191 | alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER, |
| 192 | CRYPTO_ALG_TYPE_MASK); |
| 193 | if (IS_ERR(alg)) |
Julia Lawall | 8db0507 | 2010-05-26 10:36:51 +1000 | [diff] [blame] | 194 | return ERR_CAST(alg); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 195 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 196 | /* Block size must be >= 4 bytes. */ |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 197 | err = -EINVAL; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 198 | if (alg->cra_blocksize < 4) |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 199 | goto out_put_alg; |
| 200 | |
Herbert Xu | 3f8214e | 2007-11-20 20:32:56 +0800 | [diff] [blame] | 201 | /* If this is false we'd fail the alignment of crypto_inc. */ |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 202 | if (alg->cra_blocksize % 4) |
Herbert Xu | 3f8214e | 2007-11-20 20:32:56 +0800 | [diff] [blame] | 203 | goto out_put_alg; |
| 204 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 205 | inst = crypto_alloc_instance("ctr", alg); |
| 206 | if (IS_ERR(inst)) |
| 207 | goto out; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 208 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 209 | inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER; |
| 210 | inst->alg.cra_priority = alg->cra_priority; |
| 211 | inst->alg.cra_blocksize = 1; |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 212 | inst->alg.cra_alignmask = alg->cra_alignmask | (__alignof__(u32) - 1); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 213 | inst->alg.cra_type = &crypto_blkcipher_type; |
| 214 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 215 | inst->alg.cra_blkcipher.ivsize = alg->cra_blocksize; |
| 216 | inst->alg.cra_blkcipher.min_keysize = alg->cra_cipher.cia_min_keysize; |
| 217 | inst->alg.cra_blkcipher.max_keysize = alg->cra_cipher.cia_max_keysize; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 218 | |
| 219 | inst->alg.cra_ctxsize = sizeof(struct crypto_ctr_ctx); |
| 220 | |
| 221 | inst->alg.cra_init = crypto_ctr_init_tfm; |
| 222 | inst->alg.cra_exit = crypto_ctr_exit_tfm; |
| 223 | |
| 224 | inst->alg.cra_blkcipher.setkey = crypto_ctr_setkey; |
| 225 | inst->alg.cra_blkcipher.encrypt = crypto_ctr_crypt; |
| 226 | inst->alg.cra_blkcipher.decrypt = crypto_ctr_crypt; |
| 227 | |
Herbert Xu | aef2713 | 2009-08-13 23:10:39 +1000 | [diff] [blame] | 228 | inst->alg.cra_blkcipher.geniv = "chainiv"; |
| 229 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 230 | out: |
| 231 | crypto_mod_put(alg); |
| 232 | return inst; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 233 | |
| 234 | out_put_alg: |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 235 | inst = ERR_PTR(err); |
| 236 | goto out; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 237 | } |
| 238 | |
| 239 | static void crypto_ctr_free(struct crypto_instance *inst) |
| 240 | { |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 241 | crypto_drop_spawn(crypto_instance_ctx(inst)); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 242 | kfree(inst); |
| 243 | } |
| 244 | |
| 245 | static struct crypto_template crypto_ctr_tmpl = { |
| 246 | .name = "ctr", |
| 247 | .alloc = crypto_ctr_alloc, |
| 248 | .free = crypto_ctr_free, |
| 249 | .module = THIS_MODULE, |
| 250 | }; |
| 251 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 252 | static int crypto_rfc3686_setkey(struct crypto_ablkcipher *parent, |
| 253 | const u8 *key, unsigned int keylen) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 254 | { |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 255 | struct crypto_rfc3686_ctx *ctx = crypto_ablkcipher_ctx(parent); |
| 256 | struct crypto_ablkcipher *child = ctx->child; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 257 | int err; |
| 258 | |
| 259 | /* the nonce is stored in bytes at end of key */ |
| 260 | if (keylen < CTR_RFC3686_NONCE_SIZE) |
| 261 | return -EINVAL; |
| 262 | |
| 263 | memcpy(ctx->nonce, key + (keylen - CTR_RFC3686_NONCE_SIZE), |
| 264 | CTR_RFC3686_NONCE_SIZE); |
| 265 | |
| 266 | keylen -= CTR_RFC3686_NONCE_SIZE; |
| 267 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 268 | crypto_ablkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); |
| 269 | crypto_ablkcipher_set_flags(child, crypto_ablkcipher_get_flags(parent) & |
| 270 | CRYPTO_TFM_REQ_MASK); |
| 271 | err = crypto_ablkcipher_setkey(child, key, keylen); |
| 272 | crypto_ablkcipher_set_flags(parent, crypto_ablkcipher_get_flags(child) & |
| 273 | CRYPTO_TFM_RES_MASK); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 274 | |
| 275 | return err; |
| 276 | } |
| 277 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 278 | static int crypto_rfc3686_crypt(struct ablkcipher_request *req) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 279 | { |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 280 | struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req); |
| 281 | struct crypto_rfc3686_ctx *ctx = crypto_ablkcipher_ctx(tfm); |
| 282 | struct crypto_ablkcipher *child = ctx->child; |
| 283 | unsigned long align = crypto_ablkcipher_alignmask(tfm); |
| 284 | struct crypto_rfc3686_req_ctx *rctx = |
| 285 | (void *)PTR_ALIGN((u8 *)ablkcipher_request_ctx(req), align + 1); |
| 286 | struct ablkcipher_request *subreq = &rctx->subreq; |
| 287 | u8 *iv = rctx->iv; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 288 | |
| 289 | /* set up counter block */ |
| 290 | memcpy(iv, ctx->nonce, CTR_RFC3686_NONCE_SIZE); |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 291 | memcpy(iv + CTR_RFC3686_NONCE_SIZE, req->info, CTR_RFC3686_IV_SIZE); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 292 | |
| 293 | /* initialize counter portion of counter block */ |
| 294 | *(__be32 *)(iv + CTR_RFC3686_NONCE_SIZE + CTR_RFC3686_IV_SIZE) = |
| 295 | cpu_to_be32(1); |
| 296 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 297 | ablkcipher_request_set_tfm(subreq, child); |
| 298 | ablkcipher_request_set_callback(subreq, req->base.flags, |
| 299 | req->base.complete, req->base.data); |
| 300 | ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->nbytes, |
| 301 | iv); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 302 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 303 | return crypto_ablkcipher_encrypt(subreq); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 304 | } |
| 305 | |
| 306 | static int crypto_rfc3686_init_tfm(struct crypto_tfm *tfm) |
| 307 | { |
| 308 | struct crypto_instance *inst = (void *)tfm->__crt_alg; |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 309 | struct crypto_skcipher_spawn *spawn = crypto_instance_ctx(inst); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 310 | struct crypto_rfc3686_ctx *ctx = crypto_tfm_ctx(tfm); |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 311 | struct crypto_ablkcipher *cipher; |
| 312 | unsigned long align; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 313 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 314 | cipher = crypto_spawn_skcipher(spawn); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 315 | if (IS_ERR(cipher)) |
| 316 | return PTR_ERR(cipher); |
| 317 | |
| 318 | ctx->child = cipher; |
| 319 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 320 | align = crypto_tfm_alg_alignmask(tfm); |
| 321 | align &= ~(crypto_tfm_ctx_alignment() - 1); |
| 322 | tfm->crt_ablkcipher.reqsize = align + |
| 323 | sizeof(struct crypto_rfc3686_req_ctx) + |
| 324 | crypto_ablkcipher_reqsize(cipher); |
| 325 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 326 | return 0; |
| 327 | } |
| 328 | |
| 329 | static void crypto_rfc3686_exit_tfm(struct crypto_tfm *tfm) |
| 330 | { |
| 331 | struct crypto_rfc3686_ctx *ctx = crypto_tfm_ctx(tfm); |
| 332 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 333 | crypto_free_ablkcipher(ctx->child); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 334 | } |
| 335 | |
| 336 | static struct crypto_instance *crypto_rfc3686_alloc(struct rtattr **tb) |
| 337 | { |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 338 | struct crypto_attr_type *algt; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 339 | struct crypto_instance *inst; |
| 340 | struct crypto_alg *alg; |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 341 | struct crypto_skcipher_spawn *spawn; |
| 342 | const char *cipher_name; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 343 | int err; |
| 344 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 345 | algt = crypto_get_attr_type(tb); |
| 346 | err = PTR_ERR(algt); |
| 347 | if (IS_ERR(algt)) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 348 | return ERR_PTR(err); |
| 349 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 350 | if ((algt->type ^ CRYPTO_ALG_TYPE_BLKCIPHER) & algt->mask) |
| 351 | return ERR_PTR(-EINVAL); |
| 352 | |
| 353 | cipher_name = crypto_attr_alg_name(tb[1]); |
| 354 | err = PTR_ERR(cipher_name); |
| 355 | if (IS_ERR(cipher_name)) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 356 | return ERR_PTR(err); |
| 357 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 358 | inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); |
| 359 | if (!inst) |
| 360 | return ERR_PTR(-ENOMEM); |
| 361 | |
| 362 | spawn = crypto_instance_ctx(inst); |
| 363 | |
| 364 | crypto_set_skcipher_spawn(spawn, inst); |
| 365 | err = crypto_grab_skcipher(spawn, cipher_name, 0, |
| 366 | crypto_requires_sync(algt->type, |
| 367 | algt->mask)); |
| 368 | if (err) |
| 369 | goto err_free_inst; |
| 370 | |
| 371 | alg = crypto_skcipher_spawn_alg(spawn); |
| 372 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 373 | /* We only support 16-byte blocks. */ |
| 374 | err = -EINVAL; |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 375 | if (alg->cra_ablkcipher.ivsize != CTR_RFC3686_BLOCK_SIZE) |
| 376 | goto err_drop_spawn; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 377 | |
| 378 | /* Not a stream cipher? */ |
| 379 | if (alg->cra_blocksize != 1) |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 380 | goto err_drop_spawn; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 381 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 382 | err = -ENAMETOOLONG; |
| 383 | if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "rfc3686(%s)", |
| 384 | alg->cra_name) >= CRYPTO_MAX_ALG_NAME) |
| 385 | goto err_drop_spawn; |
| 386 | if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, |
| 387 | "rfc3686(%s)", alg->cra_driver_name) >= |
| 388 | CRYPTO_MAX_ALG_NAME) |
| 389 | goto err_drop_spawn; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 390 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 391 | inst->alg.cra_priority = alg->cra_priority; |
| 392 | inst->alg.cra_blocksize = 1; |
| 393 | inst->alg.cra_alignmask = alg->cra_alignmask; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 394 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 395 | inst->alg.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | |
| 396 | (alg->cra_flags & CRYPTO_ALG_ASYNC); |
| 397 | inst->alg.cra_type = &crypto_ablkcipher_type; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 398 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 399 | inst->alg.cra_ablkcipher.ivsize = CTR_RFC3686_IV_SIZE; |
| 400 | inst->alg.cra_ablkcipher.min_keysize = |
| 401 | alg->cra_ablkcipher.min_keysize + CTR_RFC3686_NONCE_SIZE; |
| 402 | inst->alg.cra_ablkcipher.max_keysize = |
| 403 | alg->cra_ablkcipher.max_keysize + CTR_RFC3686_NONCE_SIZE; |
| 404 | |
| 405 | inst->alg.cra_ablkcipher.geniv = "seqiv"; |
| 406 | |
| 407 | inst->alg.cra_ablkcipher.setkey = crypto_rfc3686_setkey; |
| 408 | inst->alg.cra_ablkcipher.encrypt = crypto_rfc3686_crypt; |
| 409 | inst->alg.cra_ablkcipher.decrypt = crypto_rfc3686_crypt; |
Herbert Xu | 0a27032 | 2007-11-30 21:38:37 +1100 | [diff] [blame] | 410 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 411 | inst->alg.cra_ctxsize = sizeof(struct crypto_rfc3686_ctx); |
| 412 | |
| 413 | inst->alg.cra_init = crypto_rfc3686_init_tfm; |
| 414 | inst->alg.cra_exit = crypto_rfc3686_exit_tfm; |
| 415 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 416 | return inst; |
| 417 | |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 418 | err_drop_spawn: |
| 419 | crypto_drop_skcipher(spawn); |
| 420 | err_free_inst: |
| 421 | kfree(inst); |
| 422 | return ERR_PTR(err); |
| 423 | } |
| 424 | |
| 425 | static void crypto_rfc3686_free(struct crypto_instance *inst) |
| 426 | { |
| 427 | struct crypto_skcipher_spawn *spawn = crypto_instance_ctx(inst); |
| 428 | |
| 429 | crypto_drop_skcipher(spawn); |
| 430 | kfree(inst); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 431 | } |
| 432 | |
| 433 | static struct crypto_template crypto_rfc3686_tmpl = { |
| 434 | .name = "rfc3686", |
| 435 | .alloc = crypto_rfc3686_alloc, |
Jussi Kivilinna | 69d3150 | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 436 | .free = crypto_rfc3686_free, |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 437 | .module = THIS_MODULE, |
| 438 | }; |
| 439 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 440 | static int __init crypto_ctr_module_init(void) |
| 441 | { |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 442 | int err; |
| 443 | |
| 444 | err = crypto_register_template(&crypto_ctr_tmpl); |
| 445 | if (err) |
| 446 | goto out; |
| 447 | |
| 448 | err = crypto_register_template(&crypto_rfc3686_tmpl); |
| 449 | if (err) |
| 450 | goto out_drop_ctr; |
| 451 | |
| 452 | out: |
| 453 | return err; |
| 454 | |
| 455 | out_drop_ctr: |
| 456 | crypto_unregister_template(&crypto_ctr_tmpl); |
| 457 | goto out; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 458 | } |
| 459 | |
| 460 | static void __exit crypto_ctr_module_exit(void) |
| 461 | { |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 462 | crypto_unregister_template(&crypto_rfc3686_tmpl); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 463 | crypto_unregister_template(&crypto_ctr_tmpl); |
| 464 | } |
| 465 | |
| 466 | module_init(crypto_ctr_module_init); |
| 467 | module_exit(crypto_ctr_module_exit); |
| 468 | |
| 469 | MODULE_LICENSE("GPL"); |
| 470 | MODULE_DESCRIPTION("CTR Counter block mode"); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 471 | MODULE_ALIAS("rfc3686"); |