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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /crypto/pcbc.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | crypto/pcbc.c | 306 |
1 files changed, 306 insertions, 0 deletions
diff --git a/crypto/pcbc.c b/crypto/pcbc.c new file mode 100644 index 000000000..1b182dfed --- /dev/null +++ b/crypto/pcbc.c @@ -0,0 +1,306 @@ +/* + * PCBC: Propagating Cipher Block Chaining mode + * + * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * Derived from cbc.c + * - Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + */ + +#include <crypto/algapi.h> +#include <crypto/internal/skcipher.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/compiler.h> + +struct crypto_pcbc_ctx { + struct crypto_cipher *child; +}; + +static int crypto_pcbc_setkey(struct crypto_skcipher *parent, const u8 *key, + unsigned int keylen) +{ + struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(parent); + struct crypto_cipher *child = ctx->child; + int err; + + crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_cipher_set_flags(child, crypto_skcipher_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + err = crypto_cipher_setkey(child, key, keylen); + crypto_skcipher_set_flags(parent, crypto_cipher_get_flags(child) & + CRYPTO_TFM_RES_MASK); + return err; +} + +static int crypto_pcbc_encrypt_segment(struct skcipher_request *req, + struct skcipher_walk *walk, + struct crypto_cipher *tfm) +{ + int bsize = crypto_cipher_blocksize(tfm); + unsigned int nbytes = walk->nbytes; + u8 *src = walk->src.virt.addr; + u8 *dst = walk->dst.virt.addr; + u8 * const iv = walk->iv; + + do { + crypto_xor(iv, src, bsize); + crypto_cipher_encrypt_one(tfm, dst, iv); + crypto_xor_cpy(iv, dst, src, bsize); + + src += bsize; + dst += bsize; + } while ((nbytes -= bsize) >= bsize); + + return nbytes; +} + +static int crypto_pcbc_encrypt_inplace(struct skcipher_request *req, + struct skcipher_walk *walk, + struct crypto_cipher *tfm) +{ + int bsize = crypto_cipher_blocksize(tfm); + unsigned int nbytes = walk->nbytes; + u8 *src = walk->src.virt.addr; + u8 * const iv = walk->iv; + u8 tmpbuf[MAX_CIPHER_BLOCKSIZE]; + + do { + memcpy(tmpbuf, src, bsize); + crypto_xor(iv, src, bsize); + crypto_cipher_encrypt_one(tfm, src, iv); + crypto_xor_cpy(iv, tmpbuf, src, bsize); + + src += bsize; + } while ((nbytes -= bsize) >= bsize); + + return nbytes; +} + +static int crypto_pcbc_encrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm); + struct crypto_cipher *child = ctx->child; + struct skcipher_walk walk; + unsigned int nbytes; + int err; + + err = skcipher_walk_virt(&walk, req, false); + + while ((nbytes = walk.nbytes)) { + if (walk.src.virt.addr == walk.dst.virt.addr) + nbytes = crypto_pcbc_encrypt_inplace(req, &walk, + child); + else + nbytes = crypto_pcbc_encrypt_segment(req, &walk, + child); + err = skcipher_walk_done(&walk, nbytes); + } + + return err; +} + +static int crypto_pcbc_decrypt_segment(struct skcipher_request *req, + struct skcipher_walk *walk, + struct crypto_cipher *tfm) +{ + int bsize = crypto_cipher_blocksize(tfm); + unsigned int nbytes = walk->nbytes; + u8 *src = walk->src.virt.addr; + u8 *dst = walk->dst.virt.addr; + u8 * const iv = walk->iv; + + do { + crypto_cipher_decrypt_one(tfm, dst, src); + crypto_xor(dst, iv, bsize); + crypto_xor_cpy(iv, dst, src, bsize); + + src += bsize; + dst += bsize; + } while ((nbytes -= bsize) >= bsize); + + return nbytes; +} + +static int crypto_pcbc_decrypt_inplace(struct skcipher_request *req, + struct skcipher_walk *walk, + struct crypto_cipher *tfm) +{ + int bsize = crypto_cipher_blocksize(tfm); + unsigned int nbytes = walk->nbytes; + u8 *src = walk->src.virt.addr; + u8 * const iv = walk->iv; + u8 tmpbuf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(u32)); + + do { + memcpy(tmpbuf, src, bsize); + crypto_cipher_decrypt_one(tfm, src, src); + crypto_xor(src, iv, bsize); + crypto_xor_cpy(iv, src, tmpbuf, bsize); + + src += bsize; + } while ((nbytes -= bsize) >= bsize); + + return nbytes; +} + +static int crypto_pcbc_decrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm); + struct crypto_cipher *child = ctx->child; + struct skcipher_walk walk; + unsigned int nbytes; + int err; + + err = skcipher_walk_virt(&walk, req, false); + + while ((nbytes = walk.nbytes)) { + if (walk.src.virt.addr == walk.dst.virt.addr) + nbytes = crypto_pcbc_decrypt_inplace(req, &walk, + child); + else + nbytes = crypto_pcbc_decrypt_segment(req, &walk, + child); + err = skcipher_walk_done(&walk, nbytes); + } + + return err; +} + +static int crypto_pcbc_init_tfm(struct crypto_skcipher *tfm) +{ + struct skcipher_instance *inst = skcipher_alg_instance(tfm); + struct crypto_spawn *spawn = skcipher_instance_ctx(inst); + struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm); + struct crypto_cipher *cipher; + + cipher = crypto_spawn_cipher(spawn); + if (IS_ERR(cipher)) + return PTR_ERR(cipher); + + ctx->child = cipher; + return 0; +} + +static void crypto_pcbc_exit_tfm(struct crypto_skcipher *tfm) +{ + struct crypto_pcbc_ctx *ctx = crypto_skcipher_ctx(tfm); + + crypto_free_cipher(ctx->child); +} + +static void crypto_pcbc_free(struct skcipher_instance *inst) +{ + crypto_drop_skcipher(skcipher_instance_ctx(inst)); + kfree(inst); +} + +static int crypto_pcbc_create(struct crypto_template *tmpl, struct rtattr **tb) +{ + struct skcipher_instance *inst; + struct crypto_attr_type *algt; + struct crypto_spawn *spawn; + struct crypto_alg *alg; + int err; + + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return PTR_ERR(algt); + + if (((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) & + ~CRYPTO_ALG_INTERNAL) + return -EINVAL; + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return -ENOMEM; + + alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER | + (algt->type & CRYPTO_ALG_INTERNAL), + CRYPTO_ALG_TYPE_MASK | + (algt->mask & CRYPTO_ALG_INTERNAL)); + err = PTR_ERR(alg); + if (IS_ERR(alg)) + goto err_free_inst; + + spawn = skcipher_instance_ctx(inst); + err = crypto_init_spawn(spawn, alg, skcipher_crypto_instance(inst), + CRYPTO_ALG_TYPE_MASK); + if (err) + goto err_put_alg; + + err = crypto_inst_setname(skcipher_crypto_instance(inst), "pcbc", alg); + if (err) + goto err_drop_spawn; + + inst->alg.base.cra_flags = alg->cra_flags & CRYPTO_ALG_INTERNAL; + inst->alg.base.cra_priority = alg->cra_priority; + inst->alg.base.cra_blocksize = alg->cra_blocksize; + inst->alg.base.cra_alignmask = alg->cra_alignmask; + + inst->alg.ivsize = alg->cra_blocksize; + inst->alg.min_keysize = alg->cra_cipher.cia_min_keysize; + inst->alg.max_keysize = alg->cra_cipher.cia_max_keysize; + + inst->alg.base.cra_ctxsize = sizeof(struct crypto_pcbc_ctx); + + inst->alg.init = crypto_pcbc_init_tfm; + inst->alg.exit = crypto_pcbc_exit_tfm; + + inst->alg.setkey = crypto_pcbc_setkey; + inst->alg.encrypt = crypto_pcbc_encrypt; + inst->alg.decrypt = crypto_pcbc_decrypt; + + inst->free = crypto_pcbc_free; + + err = skcipher_register_instance(tmpl, inst); + if (err) + goto err_drop_spawn; + crypto_mod_put(alg); + +out: + return err; + +err_drop_spawn: + crypto_drop_spawn(spawn); +err_put_alg: + crypto_mod_put(alg); +err_free_inst: + kfree(inst); + goto out; +} + +static struct crypto_template crypto_pcbc_tmpl = { + .name = "pcbc", + .create = crypto_pcbc_create, + .module = THIS_MODULE, +}; + +static int __init crypto_pcbc_module_init(void) +{ + return crypto_register_template(&crypto_pcbc_tmpl); +} + +static void __exit crypto_pcbc_module_exit(void) +{ + crypto_unregister_template(&crypto_pcbc_tmpl); +} + +module_init(crypto_pcbc_module_init); +module_exit(crypto_pcbc_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("PCBC block cipher algorithm"); +MODULE_ALIAS_CRYPTO("pcbc"); |