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 | 69d3150c | 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 { |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 29 | struct crypto_skcipher *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 | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 33 | struct crypto_rfc3686_req_ctx { |
| 34 | u8 iv[CTR_RFC3686_BLOCK_SIZE]; |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 35 | struct skcipher_request subreq CRYPTO_MINALIGN_ATTR; |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 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); |
Ard Biesheuvel | 45fe93d | 2017-07-24 11:28:04 +0100 | [diff] [blame] | 68 | crypto_xor_cpy(dst, keystream, src, nbytes); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 69 | |
| 70 | crypto_inc(ctrblk, bsize); |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 71 | } |
| 72 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 73 | static int crypto_ctr_crypt_segment(struct blkcipher_walk *walk, |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 74 | struct crypto_cipher *tfm) |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 75 | { |
| 76 | void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = |
| 77 | crypto_cipher_alg(tfm)->cia_encrypt; |
| 78 | unsigned int bsize = crypto_cipher_blocksize(tfm); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 79 | u8 *ctrblk = walk->iv; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 80 | u8 *src = walk->src.virt.addr; |
| 81 | u8 *dst = walk->dst.virt.addr; |
| 82 | unsigned int nbytes = walk->nbytes; |
| 83 | |
| 84 | do { |
| 85 | /* create keystream */ |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 86 | fn(crypto_cipher_tfm(tfm), dst, ctrblk); |
| 87 | crypto_xor(dst, src, bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 88 | |
| 89 | /* increment counter in counterblock */ |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 90 | crypto_inc(ctrblk, bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 91 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 92 | src += bsize; |
| 93 | dst += bsize; |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 94 | } while ((nbytes -= bsize) >= bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 95 | |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 96 | return nbytes; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 97 | } |
| 98 | |
| 99 | static int crypto_ctr_crypt_inplace(struct blkcipher_walk *walk, |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 100 | struct crypto_cipher *tfm) |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 101 | { |
| 102 | void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = |
| 103 | crypto_cipher_alg(tfm)->cia_encrypt; |
| 104 | unsigned int bsize = crypto_cipher_blocksize(tfm); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 105 | unsigned long alignmask = crypto_cipher_alignmask(tfm); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 106 | unsigned int nbytes = walk->nbytes; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 107 | u8 *ctrblk = walk->iv; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 108 | u8 *src = walk->src.virt.addr; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 109 | u8 tmp[bsize + alignmask]; |
| 110 | u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 111 | |
| 112 | do { |
| 113 | /* create keystream */ |
| 114 | fn(crypto_cipher_tfm(tfm), keystream, ctrblk); |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 115 | crypto_xor(src, keystream, bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 116 | |
| 117 | /* increment counter in counterblock */ |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 118 | crypto_inc(ctrblk, bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 119 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 120 | src += bsize; |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 121 | } while ((nbytes -= bsize) >= bsize); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 122 | |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 123 | return nbytes; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 124 | } |
| 125 | |
| 126 | static int crypto_ctr_crypt(struct blkcipher_desc *desc, |
| 127 | struct scatterlist *dst, struct scatterlist *src, |
| 128 | unsigned int nbytes) |
| 129 | { |
| 130 | struct blkcipher_walk walk; |
| 131 | struct crypto_blkcipher *tfm = desc->tfm; |
| 132 | struct crypto_ctr_ctx *ctx = crypto_blkcipher_ctx(tfm); |
| 133 | struct crypto_cipher *child = ctx->child; |
| 134 | unsigned int bsize = crypto_cipher_blocksize(child); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 135 | int err; |
| 136 | |
| 137 | blkcipher_walk_init(&walk, dst, src, nbytes); |
| 138 | err = blkcipher_walk_virt_block(desc, &walk, bsize); |
| 139 | |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 140 | while (walk.nbytes >= bsize) { |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 141 | if (walk.src.virt.addr == walk.dst.virt.addr) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 142 | nbytes = crypto_ctr_crypt_inplace(&walk, child); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 143 | else |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 144 | nbytes = crypto_ctr_crypt_segment(&walk, child); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 145 | |
| 146 | err = blkcipher_walk_done(desc, &walk, nbytes); |
| 147 | } |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 148 | |
| 149 | if (walk.nbytes) { |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 150 | crypto_ctr_crypt_final(&walk, child); |
Herbert Xu | 0971eb0 | 2007-11-30 00:23:53 +1100 | [diff] [blame] | 151 | err = blkcipher_walk_done(desc, &walk, 0); |
| 152 | } |
| 153 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 154 | return err; |
| 155 | } |
| 156 | |
| 157 | static int crypto_ctr_init_tfm(struct crypto_tfm *tfm) |
| 158 | { |
| 159 | struct crypto_instance *inst = (void *)tfm->__crt_alg; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 160 | struct crypto_spawn *spawn = crypto_instance_ctx(inst); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 161 | struct crypto_ctr_ctx *ctx = crypto_tfm_ctx(tfm); |
| 162 | struct crypto_cipher *cipher; |
| 163 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 164 | cipher = crypto_spawn_cipher(spawn); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 165 | if (IS_ERR(cipher)) |
| 166 | return PTR_ERR(cipher); |
| 167 | |
| 168 | ctx->child = cipher; |
| 169 | |
| 170 | return 0; |
| 171 | } |
| 172 | |
| 173 | static void crypto_ctr_exit_tfm(struct crypto_tfm *tfm) |
| 174 | { |
| 175 | struct crypto_ctr_ctx *ctx = crypto_tfm_ctx(tfm); |
| 176 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 177 | crypto_free_cipher(ctx->child); |
| 178 | } |
| 179 | |
| 180 | static struct crypto_instance *crypto_ctr_alloc(struct rtattr **tb) |
| 181 | { |
| 182 | struct crypto_instance *inst; |
Marcelo Cerri | d2c2a85 | 2017-02-27 09:38:26 -0300 | [diff] [blame] | 183 | struct crypto_attr_type *algt; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 184 | struct crypto_alg *alg; |
Marcelo Cerri | d2c2a85 | 2017-02-27 09:38:26 -0300 | [diff] [blame] | 185 | u32 mask; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 186 | int err; |
| 187 | |
| 188 | err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER); |
| 189 | if (err) |
| 190 | return ERR_PTR(err); |
| 191 | |
Marcelo Cerri | d2c2a85 | 2017-02-27 09:38:26 -0300 | [diff] [blame] | 192 | algt = crypto_get_attr_type(tb); |
| 193 | if (IS_ERR(algt)) |
| 194 | return ERR_CAST(algt); |
| 195 | |
| 196 | mask = CRYPTO_ALG_TYPE_MASK | |
| 197 | crypto_requires_off(algt->type, algt->mask, |
| 198 | CRYPTO_ALG_NEED_FALLBACK); |
| 199 | |
| 200 | alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER, mask); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 201 | if (IS_ERR(alg)) |
Julia Lawall | 8db05078 | 2010-05-26 10:36:51 +1000 | [diff] [blame] | 202 | return ERR_CAST(alg); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 203 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 204 | /* Block size must be >= 4 bytes. */ |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 205 | err = -EINVAL; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 206 | if (alg->cra_blocksize < 4) |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 207 | goto out_put_alg; |
| 208 | |
Herbert Xu | 3f8214e | 2007-11-20 20:32:56 +0800 | [diff] [blame] | 209 | /* If this is false we'd fail the alignment of crypto_inc. */ |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 210 | if (alg->cra_blocksize % 4) |
Herbert Xu | 3f8214e | 2007-11-20 20:32:56 +0800 | [diff] [blame] | 211 | goto out_put_alg; |
| 212 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 213 | inst = crypto_alloc_instance("ctr", alg); |
| 214 | if (IS_ERR(inst)) |
| 215 | goto out; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 216 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 217 | inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER; |
| 218 | inst->alg.cra_priority = alg->cra_priority; |
| 219 | inst->alg.cra_blocksize = 1; |
Ard Biesheuvel | db91af0 | 2017-02-05 10:06:12 +0000 | [diff] [blame] | 220 | inst->alg.cra_alignmask = alg->cra_alignmask; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 221 | inst->alg.cra_type = &crypto_blkcipher_type; |
| 222 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 223 | inst->alg.cra_blkcipher.ivsize = alg->cra_blocksize; |
| 224 | inst->alg.cra_blkcipher.min_keysize = alg->cra_cipher.cia_min_keysize; |
| 225 | inst->alg.cra_blkcipher.max_keysize = alg->cra_cipher.cia_max_keysize; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 226 | |
| 227 | inst->alg.cra_ctxsize = sizeof(struct crypto_ctr_ctx); |
| 228 | |
| 229 | inst->alg.cra_init = crypto_ctr_init_tfm; |
| 230 | inst->alg.cra_exit = crypto_ctr_exit_tfm; |
| 231 | |
| 232 | inst->alg.cra_blkcipher.setkey = crypto_ctr_setkey; |
| 233 | inst->alg.cra_blkcipher.encrypt = crypto_ctr_crypt; |
| 234 | inst->alg.cra_blkcipher.decrypt = crypto_ctr_crypt; |
| 235 | |
Herbert Xu | aef2713 | 2009-08-13 23:10:39 +1000 | [diff] [blame] | 236 | inst->alg.cra_blkcipher.geniv = "chainiv"; |
| 237 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 238 | out: |
| 239 | crypto_mod_put(alg); |
| 240 | return inst; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 241 | |
| 242 | out_put_alg: |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 243 | inst = ERR_PTR(err); |
| 244 | goto out; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 245 | } |
| 246 | |
| 247 | static void crypto_ctr_free(struct crypto_instance *inst) |
| 248 | { |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 249 | crypto_drop_spawn(crypto_instance_ctx(inst)); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 250 | kfree(inst); |
| 251 | } |
| 252 | |
| 253 | static struct crypto_template crypto_ctr_tmpl = { |
| 254 | .name = "ctr", |
| 255 | .alloc = crypto_ctr_alloc, |
| 256 | .free = crypto_ctr_free, |
| 257 | .module = THIS_MODULE, |
| 258 | }; |
| 259 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 260 | static int crypto_rfc3686_setkey(struct crypto_skcipher *parent, |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 261 | const u8 *key, unsigned int keylen) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 262 | { |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 263 | struct crypto_rfc3686_ctx *ctx = crypto_skcipher_ctx(parent); |
| 264 | struct crypto_skcipher *child = ctx->child; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 265 | int err; |
| 266 | |
| 267 | /* the nonce is stored in bytes at end of key */ |
| 268 | if (keylen < CTR_RFC3686_NONCE_SIZE) |
| 269 | return -EINVAL; |
| 270 | |
| 271 | memcpy(ctx->nonce, key + (keylen - CTR_RFC3686_NONCE_SIZE), |
| 272 | CTR_RFC3686_NONCE_SIZE); |
| 273 | |
| 274 | keylen -= CTR_RFC3686_NONCE_SIZE; |
| 275 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 276 | crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); |
| 277 | crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) & |
| 278 | CRYPTO_TFM_REQ_MASK); |
| 279 | err = crypto_skcipher_setkey(child, key, keylen); |
| 280 | crypto_skcipher_set_flags(parent, crypto_skcipher_get_flags(child) & |
| 281 | CRYPTO_TFM_RES_MASK); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 282 | |
| 283 | return err; |
| 284 | } |
| 285 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 286 | static int crypto_rfc3686_crypt(struct skcipher_request *req) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 287 | { |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 288 | struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| 289 | struct crypto_rfc3686_ctx *ctx = crypto_skcipher_ctx(tfm); |
| 290 | struct crypto_skcipher *child = ctx->child; |
| 291 | unsigned long align = crypto_skcipher_alignmask(tfm); |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 292 | struct crypto_rfc3686_req_ctx *rctx = |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 293 | (void *)PTR_ALIGN((u8 *)skcipher_request_ctx(req), align + 1); |
| 294 | struct skcipher_request *subreq = &rctx->subreq; |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 295 | u8 *iv = rctx->iv; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 296 | |
| 297 | /* set up counter block */ |
| 298 | memcpy(iv, ctx->nonce, CTR_RFC3686_NONCE_SIZE); |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 299 | memcpy(iv + CTR_RFC3686_NONCE_SIZE, req->iv, CTR_RFC3686_IV_SIZE); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 300 | |
| 301 | /* initialize counter portion of counter block */ |
| 302 | *(__be32 *)(iv + CTR_RFC3686_NONCE_SIZE + CTR_RFC3686_IV_SIZE) = |
| 303 | cpu_to_be32(1); |
| 304 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 305 | skcipher_request_set_tfm(subreq, child); |
| 306 | skcipher_request_set_callback(subreq, req->base.flags, |
| 307 | req->base.complete, req->base.data); |
| 308 | skcipher_request_set_crypt(subreq, req->src, req->dst, |
| 309 | req->cryptlen, iv); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 310 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 311 | return crypto_skcipher_encrypt(subreq); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 312 | } |
| 313 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 314 | static int crypto_rfc3686_init_tfm(struct crypto_skcipher *tfm) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 315 | { |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 316 | struct skcipher_instance *inst = skcipher_alg_instance(tfm); |
| 317 | struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst); |
| 318 | struct crypto_rfc3686_ctx *ctx = crypto_skcipher_ctx(tfm); |
| 319 | struct crypto_skcipher *cipher; |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 320 | unsigned long align; |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 321 | unsigned int reqsize; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 322 | |
Eric Biggers | 60425a8 | 2016-10-28 09:52:19 -0700 | [diff] [blame] | 323 | cipher = crypto_spawn_skcipher(spawn); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 324 | if (IS_ERR(cipher)) |
| 325 | return PTR_ERR(cipher); |
| 326 | |
| 327 | ctx->child = cipher; |
| 328 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 329 | align = crypto_skcipher_alignmask(tfm); |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 330 | align &= ~(crypto_tfm_ctx_alignment() - 1); |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 331 | reqsize = align + sizeof(struct crypto_rfc3686_req_ctx) + |
| 332 | crypto_skcipher_reqsize(cipher); |
| 333 | crypto_skcipher_set_reqsize(tfm, reqsize); |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 334 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 335 | return 0; |
| 336 | } |
| 337 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 338 | static void crypto_rfc3686_exit_tfm(struct crypto_skcipher *tfm) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 339 | { |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 340 | struct crypto_rfc3686_ctx *ctx = crypto_skcipher_ctx(tfm); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 341 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 342 | crypto_free_skcipher(ctx->child); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 343 | } |
| 344 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 345 | static void crypto_rfc3686_free(struct skcipher_instance *inst) |
| 346 | { |
| 347 | struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst); |
| 348 | |
| 349 | crypto_drop_skcipher(spawn); |
| 350 | kfree(inst); |
| 351 | } |
| 352 | |
| 353 | static int crypto_rfc3686_create(struct crypto_template *tmpl, |
| 354 | struct rtattr **tb) |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 355 | { |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 356 | struct crypto_attr_type *algt; |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 357 | struct skcipher_instance *inst; |
| 358 | struct skcipher_alg *alg; |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 359 | struct crypto_skcipher_spawn *spawn; |
| 360 | const char *cipher_name; |
Marcelo Cerri | d2c2a85 | 2017-02-27 09:38:26 -0300 | [diff] [blame] | 361 | u32 mask; |
| 362 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 363 | int err; |
| 364 | |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 365 | algt = crypto_get_attr_type(tb); |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 366 | if (IS_ERR(algt)) |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 367 | return PTR_ERR(algt); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 368 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 369 | if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) |
| 370 | return -EINVAL; |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 371 | |
| 372 | cipher_name = crypto_attr_alg_name(tb[1]); |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 373 | if (IS_ERR(cipher_name)) |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 374 | return PTR_ERR(cipher_name); |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 375 | |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 376 | inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); |
| 377 | if (!inst) |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 378 | return -ENOMEM; |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 379 | |
Marcelo Cerri | d2c2a85 | 2017-02-27 09:38:26 -0300 | [diff] [blame] | 380 | mask = crypto_requires_sync(algt->type, algt->mask) | |
| 381 | crypto_requires_off(algt->type, algt->mask, |
| 382 | CRYPTO_ALG_NEED_FALLBACK); |
| 383 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 384 | spawn = skcipher_instance_ctx(inst); |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 385 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 386 | crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst)); |
Marcelo Cerri | d2c2a85 | 2017-02-27 09:38:26 -0300 | [diff] [blame] | 387 | err = crypto_grab_skcipher(spawn, cipher_name, 0, mask); |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 388 | if (err) |
| 389 | goto err_free_inst; |
| 390 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 391 | alg = crypto_spawn_skcipher_alg(spawn); |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 392 | |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 393 | /* We only support 16-byte blocks. */ |
| 394 | err = -EINVAL; |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 395 | if (crypto_skcipher_alg_ivsize(alg) != CTR_RFC3686_BLOCK_SIZE) |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 396 | goto err_drop_spawn; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 397 | |
| 398 | /* Not a stream cipher? */ |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 399 | if (alg->base.cra_blocksize != 1) |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 400 | goto err_drop_spawn; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 401 | |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 402 | err = -ENAMETOOLONG; |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 403 | if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, |
| 404 | "rfc3686(%s)", alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME) |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 405 | goto err_drop_spawn; |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 406 | if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, |
| 407 | "rfc3686(%s)", alg->base.cra_driver_name) >= |
| 408 | CRYPTO_MAX_ALG_NAME) |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 409 | goto err_drop_spawn; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 410 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 411 | inst->alg.base.cra_priority = alg->base.cra_priority; |
| 412 | inst->alg.base.cra_blocksize = 1; |
| 413 | inst->alg.base.cra_alignmask = alg->base.cra_alignmask; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 414 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 415 | inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 416 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 417 | inst->alg.ivsize = CTR_RFC3686_IV_SIZE; |
| 418 | inst->alg.chunksize = crypto_skcipher_alg_chunksize(alg); |
| 419 | inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg) + |
| 420 | CTR_RFC3686_NONCE_SIZE; |
| 421 | inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg) + |
| 422 | CTR_RFC3686_NONCE_SIZE; |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 423 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 424 | inst->alg.setkey = crypto_rfc3686_setkey; |
| 425 | inst->alg.encrypt = crypto_rfc3686_crypt; |
| 426 | inst->alg.decrypt = crypto_rfc3686_crypt; |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 427 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 428 | inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc3686_ctx); |
Herbert Xu | 0a27032 | 2007-11-30 21:38:37 +1100 | [diff] [blame] | 429 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 430 | inst->alg.init = crypto_rfc3686_init_tfm; |
| 431 | inst->alg.exit = crypto_rfc3686_exit_tfm; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 432 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 433 | inst->free = crypto_rfc3686_free; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 434 | |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 435 | err = skcipher_register_instance(tmpl, inst); |
| 436 | if (err) |
| 437 | goto err_drop_spawn; |
| 438 | |
| 439 | out: |
| 440 | return err; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 441 | |
Jussi Kivilinna | 69d3150c | 2012-12-28 12:04:58 +0200 | [diff] [blame] | 442 | err_drop_spawn: |
| 443 | crypto_drop_skcipher(spawn); |
| 444 | err_free_inst: |
| 445 | kfree(inst); |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 446 | goto out; |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 447 | } |
| 448 | |
| 449 | static struct crypto_template crypto_rfc3686_tmpl = { |
| 450 | .name = "rfc3686", |
Herbert Xu | b2b39c2 | 2016-07-12 13:17:37 +0800 | [diff] [blame] | 451 | .create = crypto_rfc3686_create, |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 452 | .module = THIS_MODULE, |
| 453 | }; |
| 454 | |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 455 | static int __init crypto_ctr_module_init(void) |
| 456 | { |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 457 | int err; |
| 458 | |
| 459 | err = crypto_register_template(&crypto_ctr_tmpl); |
| 460 | if (err) |
| 461 | goto out; |
| 462 | |
| 463 | err = crypto_register_template(&crypto_rfc3686_tmpl); |
| 464 | if (err) |
| 465 | goto out_drop_ctr; |
| 466 | |
| 467 | out: |
| 468 | return err; |
| 469 | |
| 470 | out_drop_ctr: |
| 471 | crypto_unregister_template(&crypto_ctr_tmpl); |
| 472 | goto out; |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 473 | } |
| 474 | |
| 475 | static void __exit crypto_ctr_module_exit(void) |
| 476 | { |
Herbert Xu | 5311f24 | 2007-12-17 21:34:32 +0800 | [diff] [blame] | 477 | crypto_unregister_template(&crypto_rfc3686_tmpl); |
Joy Latten | 23e353c | 2007-10-23 08:50:32 +0800 | [diff] [blame] | 478 | crypto_unregister_template(&crypto_ctr_tmpl); |
| 479 | } |
| 480 | |
| 481 | module_init(crypto_ctr_module_init); |
| 482 | module_exit(crypto_ctr_module_exit); |
| 483 | |
| 484 | MODULE_LICENSE("GPL"); |
| 485 | MODULE_DESCRIPTION("CTR Counter block mode"); |
Kees Cook | 5d26a10 | 2014-11-20 17:05:53 -0800 | [diff] [blame] | 486 | MODULE_ALIAS_CRYPTO("rfc3686"); |
Kees Cook | 4943ba1 | 2014-11-24 16:32:38 -0800 | [diff] [blame] | 487 | MODULE_ALIAS_CRYPTO("ctr"); |