summaryrefslogtreecommitdiffstats
path: root/crypto/pcbc.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /crypto/pcbc.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'crypto/pcbc.c')
-rw-r--r--crypto/pcbc.c306
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");