crypto/speck.c - linux/kernel/git/viro/vfs - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Speck: a lightweight block cipher
  *
  * Copyright (c) 2018 Google, Inc
  *
  * Speck has 10 variants, including 5 block sizes.  For now we only implement
  * the variants Speck128/128, Speck128/192, Speck128/256, Speck64/96, and
  * Speck64/128.   Speck${B}/${K} denotes the variant with a block size of B bits
  * and a key size of K bits.  The Speck128 variants are believed to be the most
  * secure variants, and they use the same block size and key sizes as AES.  The
  * Speck64 variants are less secure, but on 32-bit processors are usually
  * faster.  The remaining variants (Speck32, Speck48, and Speck96) are even less
  * secure and/or not as well suited for implementation on either 32-bit or
  * 64-bit processors, so are omitted.
  *
  * Reference: "The Simon and Speck Families of Lightweight Block Ciphers"
  * https://eprint.iacr.org/2013/404.pdf
  *
  * In a correspondence, the Speck designers have also clarified that the words
  * should be interpreted in little-endian format, and the words should be
  * ordered such that the first word of each block is 'y' rather than 'x', and
  * the first key word (rather than the last) becomes the first round key.
  */

 #include <asm/unaligned.h>
 #include <crypto/speck.h>
 #include <linux/bitops.h>
 #include <linux/crypto.h>
 #include <linux/init.h>
 #include <linux/module.h>

 /* Speck128 */

 static __always_inline void speck128_round(u64 *x, u64 *y, u64 k)
 {
 	*x = ror64(*x, 8);
 	*x += *y;
 	*x ^= k;
 	*y = rol64(*y, 3);
 	*y ^= *x;
 }

 static __always_inline void speck128_unround(u64 *x, u64 *y, u64 k)
 {
 	*y ^= *x;
 	*y = ror64(*y, 3);
 	*x ^= k;
 	*x -= *y;
 	*x = rol64(*x, 8);
 }

 void crypto_speck128_encrypt(const struct speck128_tfm_ctx *ctx,
 			     u8 *out, const u8 *in)
 {
 	u64 y = get_unaligned_le64(in);
 	u64 x = get_unaligned_le64(in + 8);
 	int i;

 	for (i = 0; i < ctx->nrounds; i++)
 		speck128_round(&x, &y, ctx->round_keys[i]);

 	put_unaligned_le64(y, out);
 	put_unaligned_le64(x, out + 8);
 }
 EXPORT_SYMBOL_GPL(crypto_speck128_encrypt);

 static void speck128_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	crypto_speck128_encrypt(crypto_tfm_ctx(tfm), out, in);
 }

 void crypto_speck128_decrypt(const struct speck128_tfm_ctx *ctx,
 			     u8 *out, const u8 *in)
 {
 	u64 y = get_unaligned_le64(in);
 	u64 x = get_unaligned_le64(in + 8);
 	int i;

 	for (i = ctx->nrounds - 1; i >= 0; i--)
 		speck128_unround(&x, &y, ctx->round_keys[i]);

 	put_unaligned_le64(y, out);
 	put_unaligned_le64(x, out + 8);
 }
 EXPORT_SYMBOL_GPL(crypto_speck128_decrypt);

 static void speck128_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	crypto_speck128_decrypt(crypto_tfm_ctx(tfm), out, in);
 }

 int crypto_speck128_setkey(struct speck128_tfm_ctx *ctx, const u8 *key,
 			   unsigned int keylen)
 {
 	u64 l[3];
 	u64 k;
 	int i;

 	switch (keylen) {
 	case SPECK128_128_KEY_SIZE:
 		k = get_unaligned_le64(key);
 		l[0] = get_unaligned_le64(key + 8);
 		ctx->nrounds = SPECK128_128_NROUNDS;
 		for (i = 0; i < ctx->nrounds; i++) {
 			ctx->round_keys[i] = k;
 			speck128_round(&l[0], &k, i);
 		}
 		break;
 	case SPECK128_192_KEY_SIZE:
 		k = get_unaligned_le64(key);
 		l[0] = get_unaligned_le64(key + 8);
 		l[1] = get_unaligned_le64(key + 16);
 		ctx->nrounds = SPECK128_192_NROUNDS;
 		for (i = 0; i < ctx->nrounds; i++) {
 			ctx->round_keys[i] = k;
 			speck128_round(&l[i % 2], &k, i);
 		}
 		break;
 	case SPECK128_256_KEY_SIZE:
 		k = get_unaligned_le64(key);
 		l[0] = get_unaligned_le64(key + 8);
 		l[1] = get_unaligned_le64(key + 16);
 		l[2] = get_unaligned_le64(key + 24);
 		ctx->nrounds = SPECK128_256_NROUNDS;
 		for (i = 0; i < ctx->nrounds; i++) {
 			ctx->round_keys[i] = k;
 			speck128_round(&l[i % 3], &k, i);
 		}
 		break;
 	default:
 		return -EINVAL;
 	}

 	return 0;
 }
 EXPORT_SYMBOL_GPL(crypto_speck128_setkey);

 static int speck128_setkey(struct crypto_tfm *tfm, const u8 *key,
 			   unsigned int keylen)
 {
 	return crypto_speck128_setkey(crypto_tfm_ctx(tfm), key, keylen);
 }

 /* Speck64 */

 static __always_inline void speck64_round(u32 *x, u32 *y, u32 k)
 {
 	*x = ror32(*x, 8);
 	*x += *y;
 	*x ^= k;
 	*y = rol32(*y, 3);
 	*y ^= *x;
 }

 static __always_inline void speck64_unround(u32 *x, u32 *y, u32 k)
 {
 	*y ^= *x;
 	*y = ror32(*y, 3);
 	*x ^= k;
 	*x -= *y;
 	*x = rol32(*x, 8);
 }

 void crypto_speck64_encrypt(const struct speck64_tfm_ctx *ctx,
 			    u8 *out, const u8 *in)
 {
 	u32 y = get_unaligned_le32(in);
 	u32 x = get_unaligned_le32(in + 4);
 	int i;

 	for (i = 0; i < ctx->nrounds; i++)
 		speck64_round(&x, &y, ctx->round_keys[i]);

 	put_unaligned_le32(y, out);
 	put_unaligned_le32(x, out + 4);
 }
 EXPORT_SYMBOL_GPL(crypto_speck64_encrypt);

 static void speck64_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	crypto_speck64_encrypt(crypto_tfm_ctx(tfm), out, in);
 }

 void crypto_speck64_decrypt(const struct speck64_tfm_ctx *ctx,
 			    u8 *out, const u8 *in)
 {
 	u32 y = get_unaligned_le32(in);
 	u32 x = get_unaligned_le32(in + 4);
 	int i;

 	for (i = ctx->nrounds - 1; i >= 0; i--)
 		speck64_unround(&x, &y, ctx->round_keys[i]);

 	put_unaligned_le32(y, out);
 	put_unaligned_le32(x, out + 4);
 }
 EXPORT_SYMBOL_GPL(crypto_speck64_decrypt);

 static void speck64_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	crypto_speck64_decrypt(crypto_tfm_ctx(tfm), out, in);
 }

 int crypto_speck64_setkey(struct speck64_tfm_ctx *ctx, const u8 *key,
 			  unsigned int keylen)
 {
 	u32 l[3];
 	u32 k;
 	int i;

 	switch (keylen) {
 	case SPECK64_96_KEY_SIZE:
 		k = get_unaligned_le32(key);
 		l[0] = get_unaligned_le32(key + 4);
 		l[1] = get_unaligned_le32(key + 8);
 		ctx->nrounds = SPECK64_96_NROUNDS;
 		for (i = 0; i < ctx->nrounds; i++) {
 			ctx->round_keys[i] = k;
 			speck64_round(&l[i % 2], &k, i);
 		}
 		break;
 	case SPECK64_128_KEY_SIZE:
 		k = get_unaligned_le32(key);
 		l[0] = get_unaligned_le32(key + 4);
 		l[1] = get_unaligned_le32(key + 8);
 		l[2] = get_unaligned_le32(key + 12);
 		ctx->nrounds = SPECK64_128_NROUNDS;
 		for (i = 0; i < ctx->nrounds; i++) {
 			ctx->round_keys[i] = k;
 			speck64_round(&l[i % 3], &k, i);
 		}
 		break;
 	default:
 		return -EINVAL;
 	}

 	return 0;
 }
 EXPORT_SYMBOL_GPL(crypto_speck64_setkey);

 static int speck64_setkey(struct crypto_tfm *tfm, const u8 *key,
 			  unsigned int keylen)
 {
 	return crypto_speck64_setkey(crypto_tfm_ctx(tfm), key, keylen);
 }

 /* Algorithm definitions */

 static struct crypto_alg speck_algs[] = {
 	{
 		.cra_name		= "speck128",
 		.cra_driver_name	= "speck128-generic",
 		.cra_priority		= 100,
 		.cra_flags		= CRYPTO_ALG_TYPE_CIPHER,
 		.cra_blocksize		= SPECK128_BLOCK_SIZE,
 		.cra_ctxsize		= sizeof(struct speck128_tfm_ctx),
 		.cra_module		= THIS_MODULE,
 		.cra_u			= {
 			.cipher = {
 				.cia_min_keysize	= SPECK128_128_KEY_SIZE,
 				.cia_max_keysize	= SPECK128_256_KEY_SIZE,
 				.cia_setkey		= speck128_setkey,
 				.cia_encrypt		= speck128_encrypt,
 				.cia_decrypt		= speck128_decrypt
 			}
 		}
 	}, {
 		.cra_name		= "speck64",
 		.cra_driver_name	= "speck64-generic",
 		.cra_priority		= 100,
 		.cra_flags		= CRYPTO_ALG_TYPE_CIPHER,
 		.cra_blocksize		= SPECK64_BLOCK_SIZE,
 		.cra_ctxsize		= sizeof(struct speck64_tfm_ctx),
 		.cra_module		= THIS_MODULE,
 		.cra_u			= {
 			.cipher = {
 				.cia_min_keysize	= SPECK64_96_KEY_SIZE,
 				.cia_max_keysize	= SPECK64_128_KEY_SIZE,
 				.cia_setkey		= speck64_setkey,
 				.cia_encrypt		= speck64_encrypt,
 				.cia_decrypt		= speck64_decrypt
 			}
 		}
 	}
 };

 static int __init speck_module_init(void)
 {
 	return crypto_register_algs(speck_algs, ARRAY_SIZE(speck_algs));
 }

 static void __exit speck_module_exit(void)
 {
 	crypto_unregister_algs(speck_algs, ARRAY_SIZE(speck_algs));
 }

 module_init(speck_module_init);
 module_exit(speck_module_exit);

 MODULE_DESCRIPTION("Speck block cipher (generic)");
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
 MODULE_ALIAS_CRYPTO("speck128");
 MODULE_ALIAS_CRYPTO("speck128-generic");
 MODULE_ALIAS_CRYPTO("speck64");
 MODULE_ALIAS_CRYPTO("speck64-generic");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Speck: a lightweight block cipher
	*
	* Copyright (c) 2018 Google, Inc
	*
	* Speck has 10 variants, including 5 block sizes. For now we only implement
	* the variants Speck128/128, Speck128/192, Speck128/256, Speck64/96, and
	* Speck64/128. Speck${B}/${K} denotes the variant with a block size of B bits
	* and a key size of K bits. The Speck128 variants are believed to be the most
	* secure variants, and they use the same block size and key sizes as AES. The
	* Speck64 variants are less secure, but on 32-bit processors are usually
	* faster. The remaining variants (Speck32, Speck48, and Speck96) are even less
	* secure and/or not as well suited for implementation on either 32-bit or
	* 64-bit processors, so are omitted.
	*
	* Reference: "The Simon and Speck Families of Lightweight Block Ciphers"
	* https://eprint.iacr.org/2013/404.pdf
	*
	* In a correspondence, the Speck designers have also clarified that the words
	* should be interpreted in little-endian format, and the words should be
	* ordered such that the first word of each block is 'y' rather than 'x', and
	* the first key word (rather than the last) becomes the first round key.
	*/

	#include <asm/unaligned.h>
	#include <crypto/speck.h>
	#include <linux/bitops.h>
	#include <linux/crypto.h>
	#include <linux/init.h>
	#include <linux/module.h>

	/* Speck128 */

	static __always_inline void speck128_round(u64 x, u64 y, u64 k)
	{
	x = ror64(x, 8);
	x += y;
	*x ^= k;
	y = rol64(y, 3);
	y ^= x;
	}

	static __always_inline void speck128_unround(u64 x, u64 y, u64 k)
	{
	y ^= x;
	y = ror64(y, 3);
	*x ^= k;
	x -= y;
	x = rol64(x, 8);
	}

	void crypto_speck128_encrypt(const struct speck128_tfm_ctx *ctx,
	u8 out, const u8 in)
	{
	u64 y = get_unaligned_le64(in);
	u64 x = get_unaligned_le64(in + 8);
	int i;

	for (i = 0; i < ctx->nrounds; i++)
	speck128_round(&x, &y, ctx->round_keys[i]);

	put_unaligned_le64(y, out);
	put_unaligned_le64(x, out + 8);
	}
	EXPORT_SYMBOL_GPL(crypto_speck128_encrypt);

	static void speck128_encrypt(struct crypto_tfm tfm, u8 out, const u8 *in)
	{
	crypto_speck128_encrypt(crypto_tfm_ctx(tfm), out, in);
	}

	void crypto_speck128_decrypt(const struct speck128_tfm_ctx *ctx,
	u8 out, const u8 in)
	{
	u64 y = get_unaligned_le64(in);
	u64 x = get_unaligned_le64(in + 8);
	int i;

	for (i = ctx->nrounds - 1; i >= 0; i--)
	speck128_unround(&x, &y, ctx->round_keys[i]);

	put_unaligned_le64(y, out);
	put_unaligned_le64(x, out + 8);
	}
	EXPORT_SYMBOL_GPL(crypto_speck128_decrypt);

	static void speck128_decrypt(struct crypto_tfm tfm, u8 out, const u8 *in)
	{
	crypto_speck128_decrypt(crypto_tfm_ctx(tfm), out, in);
	}

	int crypto_speck128_setkey(struct speck128_tfm_ctx ctx, const u8 key,
	unsigned int keylen)
	{
	u64 l[3];
	u64 k;
	int i;

	switch (keylen) {
	case SPECK128_128_KEY_SIZE:
	k = get_unaligned_le64(key);
	l[0] = get_unaligned_le64(key + 8);
	ctx->nrounds = SPECK128_128_NROUNDS;
	for (i = 0; i < ctx->nrounds; i++) {
	ctx->round_keys[i] = k;
	speck128_round(&l[0], &k, i);
	}
	break;
	case SPECK128_192_KEY_SIZE:
	k = get_unaligned_le64(key);
	l[0] = get_unaligned_le64(key + 8);
	l[1] = get_unaligned_le64(key + 16);
	ctx->nrounds = SPECK128_192_NROUNDS;
	for (i = 0; i < ctx->nrounds; i++) {
	ctx->round_keys[i] = k;
	speck128_round(&l[i % 2], &k, i);
	}
	break;
	case SPECK128_256_KEY_SIZE:
	k = get_unaligned_le64(key);
	l[0] = get_unaligned_le64(key + 8);
	l[1] = get_unaligned_le64(key + 16);
	l[2] = get_unaligned_le64(key + 24);
	ctx->nrounds = SPECK128_256_NROUNDS;
	for (i = 0; i < ctx->nrounds; i++) {
	ctx->round_keys[i] = k;
	speck128_round(&l[i % 3], &k, i);
	}
	break;
	default:
	return -EINVAL;
	}

	return 0;
	}
	EXPORT_SYMBOL_GPL(crypto_speck128_setkey);

	static int speck128_setkey(struct crypto_tfm tfm, const u8 key,
	unsigned int keylen)
	{
	return crypto_speck128_setkey(crypto_tfm_ctx(tfm), key, keylen);
	}

	/* Speck64 */

	static __always_inline void speck64_round(u32 x, u32 y, u32 k)
	{
	x = ror32(x, 8);
	x += y;
	*x ^= k;
	y = rol32(y, 3);
	y ^= x;
	}

	static __always_inline void speck64_unround(u32 x, u32 y, u32 k)
	{
	y ^= x;
	y = ror32(y, 3);
	*x ^= k;
	x -= y;
	x = rol32(x, 8);
	}

	void crypto_speck64_encrypt(const struct speck64_tfm_ctx *ctx,
	u8 out, const u8 in)
	{
	u32 y = get_unaligned_le32(in);
	u32 x = get_unaligned_le32(in + 4);
	int i;

	for (i = 0; i < ctx->nrounds; i++)
	speck64_round(&x, &y, ctx->round_keys[i]);

	put_unaligned_le32(y, out);
	put_unaligned_le32(x, out + 4);
	}
	EXPORT_SYMBOL_GPL(crypto_speck64_encrypt);

	static void speck64_encrypt(struct crypto_tfm tfm, u8 out, const u8 *in)
	{
	crypto_speck64_encrypt(crypto_tfm_ctx(tfm), out, in);
	}

	void crypto_speck64_decrypt(const struct speck64_tfm_ctx *ctx,
	u8 out, const u8 in)
	{
	u32 y = get_unaligned_le32(in);
	u32 x = get_unaligned_le32(in + 4);
	int i;

	for (i = ctx->nrounds - 1; i >= 0; i--)
	speck64_unround(&x, &y, ctx->round_keys[i]);

	put_unaligned_le32(y, out);
	put_unaligned_le32(x, out + 4);
	}
	EXPORT_SYMBOL_GPL(crypto_speck64_decrypt);

	static void speck64_decrypt(struct crypto_tfm tfm, u8 out, const u8 *in)
	{
	crypto_speck64_decrypt(crypto_tfm_ctx(tfm), out, in);
	}

	int crypto_speck64_setkey(struct speck64_tfm_ctx ctx, const u8 key,
	unsigned int keylen)
	{
	u32 l[3];
	u32 k;
	int i;

	switch (keylen) {
	case SPECK64_96_KEY_SIZE:
	k = get_unaligned_le32(key);
	l[0] = get_unaligned_le32(key + 4);
	l[1] = get_unaligned_le32(key + 8);
	ctx->nrounds = SPECK64_96_NROUNDS;
	for (i = 0; i < ctx->nrounds; i++) {
	ctx->round_keys[i] = k;
	speck64_round(&l[i % 2], &k, i);
	}
	break;
	case SPECK64_128_KEY_SIZE:
	k = get_unaligned_le32(key);
	l[0] = get_unaligned_le32(key + 4);
	l[1] = get_unaligned_le32(key + 8);
	l[2] = get_unaligned_le32(key + 12);
	ctx->nrounds = SPECK64_128_NROUNDS;
	for (i = 0; i < ctx->nrounds; i++) {
	ctx->round_keys[i] = k;
	speck64_round(&l[i % 3], &k, i);
	}
	break;
	default:
	return -EINVAL;
	}

	return 0;
	}
	EXPORT_SYMBOL_GPL(crypto_speck64_setkey);

	static int speck64_setkey(struct crypto_tfm tfm, const u8 key,
	unsigned int keylen)
	{
	return crypto_speck64_setkey(crypto_tfm_ctx(tfm), key, keylen);
	}

	/* Algorithm definitions */

	static struct crypto_alg speck_algs[] = {
	{
	.cra_name = "speck128",
	.cra_driver_name = "speck128-generic",
	.cra_priority = 100,
	.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize = SPECK128_BLOCK_SIZE,
	.cra_ctxsize = sizeof(struct speck128_tfm_ctx),
	.cra_module = THIS_MODULE,
	.cra_u = {
	.cipher = {
	.cia_min_keysize = SPECK128_128_KEY_SIZE,
	.cia_max_keysize = SPECK128_256_KEY_SIZE,
	.cia_setkey = speck128_setkey,
	.cia_encrypt = speck128_encrypt,
	.cia_decrypt = speck128_decrypt
	}
	}
	}, {
	.cra_name = "speck64",
	.cra_driver_name = "speck64-generic",
	.cra_priority = 100,
	.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize = SPECK64_BLOCK_SIZE,
	.cra_ctxsize = sizeof(struct speck64_tfm_ctx),
	.cra_module = THIS_MODULE,
	.cra_u = {
	.cipher = {
	.cia_min_keysize = SPECK64_96_KEY_SIZE,
	.cia_max_keysize = SPECK64_128_KEY_SIZE,
	.cia_setkey = speck64_setkey,
	.cia_encrypt = speck64_encrypt,
	.cia_decrypt = speck64_decrypt
	}
	}
	}
	};

	static int __init speck_module_init(void)
	{
	return crypto_register_algs(speck_algs, ARRAY_SIZE(speck_algs));
	}

	static void __exit speck_module_exit(void)
	{
	crypto_unregister_algs(speck_algs, ARRAY_SIZE(speck_algs));
	}

	module_init(speck_module_init);
	module_exit(speck_module_exit);

	MODULE_DESCRIPTION("Speck block cipher (generic)");
	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
	MODULE_ALIAS_CRYPTO("speck128");
	MODULE_ALIAS_CRYPTO("speck128-generic");
	MODULE_ALIAS_CRYPTO("speck64");
	MODULE_ALIAS_CRYPTO("speck64-generic");