Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 222 insertions, 0 deletions

diff --git a/crypto/cbc.c b/crypto/cbc.c
new file mode 100644
index 000000000..0d9509dff
--- /dev/null
+++ b/crypto/cbc.c
@@ -0,0 +1,222 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * CBC: Cipher Block Chaining mode
+ *
+ * Copyright (c) 2006-2016 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+
+#include <crypto/algapi.h>
+#include <crypto/internal/skcipher.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/module.h>
+
+static int crypto_cbc_encrypt_segment(struct skcipher_walk *walk,
+				      struct crypto_skcipher *skcipher)
+{
+	unsigned int bsize = crypto_skcipher_blocksize(skcipher);
+	void (*fn)(struct crypto_tfm *, u8 *, const u8 *);
+	unsigned int nbytes = walk->nbytes;
+	u8 *src = walk->src.virt.addr;
+	u8 *dst = walk->dst.virt.addr;
+	struct crypto_cipher *cipher;
+	struct crypto_tfm *tfm;
+	u8 *iv = walk->iv;
+
+	cipher = skcipher_cipher_simple(skcipher);
+	tfm = crypto_cipher_tfm(cipher);
+	fn = crypto_cipher_alg(cipher)->cia_encrypt;
+
+	do {
+		crypto_xor(iv, src, bsize);
+		fn(tfm, dst, iv);
+		memcpy(iv, dst, bsize);
+
+		src += bsize;
+		dst += bsize;
+	} while ((nbytes -= bsize) >= bsize);
+
+	return nbytes;
+}
+
+static int crypto_cbc_encrypt_inplace(struct skcipher_walk *walk,
+				      struct crypto_skcipher *skcipher)
+{
+	unsigned int bsize = crypto_skcipher_blocksize(skcipher);
+	void (*fn)(struct crypto_tfm *, u8 *, const u8 *);
+	unsigned int nbytes = walk->nbytes;
+	u8 *src = walk->src.virt.addr;
+	struct crypto_cipher *cipher;
+	struct crypto_tfm *tfm;
+	u8 *iv = walk->iv;
+
+	cipher = skcipher_cipher_simple(skcipher);
+	tfm = crypto_cipher_tfm(cipher);
+	fn = crypto_cipher_alg(cipher)->cia_encrypt;
+
+	do {
+		crypto_xor(src, iv, bsize);
+		fn(tfm, src, src);
+		iv = src;
+
+		src += bsize;
+	} while ((nbytes -= bsize) >= bsize);
+
+	memcpy(walk->iv, iv, bsize);
+
+	return nbytes;
+}
+
+static int crypto_cbc_encrypt(struct skcipher_request *req)
+{
+	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
+	struct skcipher_walk walk;
+	int err;
+
+	err = skcipher_walk_virt(&walk, req, false);
+
+	while (walk.nbytes) {
+		if (walk.src.virt.addr == walk.dst.virt.addr)
+			err = crypto_cbc_encrypt_inplace(&walk, skcipher);
+		else
+			err = crypto_cbc_encrypt_segment(&walk, skcipher);
+		err = skcipher_walk_done(&walk, err);
+	}
+
+	return err;
+}
+
+static int crypto_cbc_decrypt_segment(struct skcipher_walk *walk,
+				      struct crypto_skcipher *skcipher)
+{
+	unsigned int bsize = crypto_skcipher_blocksize(skcipher);
+	void (*fn)(struct crypto_tfm *, u8 *, const u8 *);
+	unsigned int nbytes = walk->nbytes;
+	u8 *src = walk->src.virt.addr;
+	u8 *dst = walk->dst.virt.addr;
+	struct crypto_cipher *cipher;
+	struct crypto_tfm *tfm;
+	u8 *iv = walk->iv;
+
+	cipher = skcipher_cipher_simple(skcipher);
+	tfm = crypto_cipher_tfm(cipher);
+	fn = crypto_cipher_alg(cipher)->cia_decrypt;
+
+	do {
+		fn(tfm, dst, src);
+		crypto_xor(dst, iv, bsize);
+		iv = src;
+
+		src += bsize;
+		dst += bsize;
+	} while ((nbytes -= bsize) >= bsize);
+
+	memcpy(walk->iv, iv, bsize);
+
+	return nbytes;
+}
+
+static int crypto_cbc_decrypt_inplace(struct skcipher_walk *walk,
+				      struct crypto_skcipher *skcipher)
+{
+	unsigned int bsize = crypto_skcipher_blocksize(skcipher);
+	void (*fn)(struct crypto_tfm *, u8 *, const u8 *);
+	unsigned int nbytes = walk->nbytes;
+	u8 *src = walk->src.virt.addr;
+	u8 last_iv[MAX_CIPHER_BLOCKSIZE];
+	struct crypto_cipher *cipher;
+	struct crypto_tfm *tfm;
+
+	cipher = skcipher_cipher_simple(skcipher);
+	tfm = crypto_cipher_tfm(cipher);
+	fn = crypto_cipher_alg(cipher)->cia_decrypt;
+
+	/* Start of the last block. */
+	src += nbytes - (nbytes & (bsize - 1)) - bsize;
+	memcpy(last_iv, src, bsize);
+
+	for (;;) {
+		fn(tfm, src, src);
+		if ((nbytes -= bsize) < bsize)
+			break;
+		crypto_xor(src, src - bsize, bsize);
+		src -= bsize;
+	}
+
+	crypto_xor(src, walk->iv, bsize);
+	memcpy(walk->iv, last_iv, bsize);
+
+	return nbytes;
+}
+
+static int crypto_cbc_decrypt(struct skcipher_request *req)
+{
+	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
+	struct skcipher_walk walk;
+	int err;
+
+	err = skcipher_walk_virt(&walk, req, false);
+
+	while (walk.nbytes) {
+		if (walk.src.virt.addr == walk.dst.virt.addr)
+			err = crypto_cbc_decrypt_inplace(&walk, skcipher);
+		else
+			err = crypto_cbc_decrypt_segment(&walk, skcipher);
+		err = skcipher_walk_done(&walk, err);
+	}
+
+	return err;
+}
+
+static int crypto_cbc_create(struct crypto_template *tmpl, struct rtattr **tb)
+{
+	struct skcipher_instance *inst;
+	struct crypto_alg *alg;
+	int err;
+
+	inst = skcipher_alloc_instance_simple(tmpl, tb);
+	if (IS_ERR(inst))
+		return PTR_ERR(inst);
+
+	alg = skcipher_ialg_simple(inst);
+
+	err = -EINVAL;
+	if (!is_power_of_2(alg->cra_blocksize))
+		goto out_free_inst;
+
+	inst->alg.encrypt = crypto_cbc_encrypt;
+	inst->alg.decrypt = crypto_cbc_decrypt;
+
+	err = skcipher_register_instance(tmpl, inst);
+	if (err) {
+out_free_inst:
+		inst->free(inst);
+	}
+
+	return err;
+}
+
+static struct crypto_template crypto_cbc_tmpl = {
+	.name = "cbc",
+	.create = crypto_cbc_create,
+	.module = THIS_MODULE,
+};
+
+static int __init crypto_cbc_module_init(void)
+{
+	return crypto_register_template(&crypto_cbc_tmpl);
+}
+
+static void __exit crypto_cbc_module_exit(void)
+{
+	crypto_unregister_template(&crypto_cbc_tmpl);
+}
+
+subsys_initcall(crypto_cbc_module_init);
+module_exit(crypto_cbc_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("CBC block cipher mode of operation");
+MODULE_ALIAS_CRYPTO("cbc");