Skip to main content
  • Home
  • Development
  • Documentation
  • Donate
  • Operational login
  • Browse the archive

swh logo
SoftwareHeritage
Software
Heritage
Archive
Features
  • Search

  • Downloads

  • Save code now

  • Add forge now

  • Help

  • 61acfe9
  • /
  • arch
  • /
  • arm64
  • /
  • crypto
  • /
  • aes-ce-glue.c
Raw File Download
Permalinks

To reference or cite the objects present in the Software Heritage archive, permalinks based on SoftWare Hash IDentifiers (SWHIDs) must be used.
Select below a type of object currently browsed in order to display its associated SWHID and permalink.

  • content
  • directory
content badge Iframe embedding
swh:1:cnt:e6b3227bbf5798188e7d233d209f5f51376e3e25
directory badge Iframe embedding
swh:1:dir:9f76c12f0d835eb45a33b6c81c6f1b71c26c93fd
Citations

This interface enables to generate software citations, provided that the root directory of browsed objects contains a citation.cff or codemeta.json file.
Select below a type of object currently browsed in order to generate citations for them.

  • content
  • directory
Generate software citation in BibTex format (requires biblatex-software package)
Generating citation ...
Generate software citation in BibTex format (requires biblatex-software package)
Generating citation ...
aes-ce-glue.c
/*
 * aes-ce-cipher.c - core AES cipher using ARMv8 Crypto Extensions
 *
 * Copyright (C) 2013 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <asm/neon.h>
#include <asm/simd.h>
#include <asm/unaligned.h>
#include <crypto/aes.h>
#include <linux/cpufeature.h>
#include <linux/crypto.h>
#include <linux/module.h>

#include "aes-ce-setkey.h"

MODULE_DESCRIPTION("Synchronous AES cipher using ARMv8 Crypto Extensions");
MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
MODULE_LICENSE("GPL v2");

asmlinkage void __aes_arm64_encrypt(u32 *rk, u8 *out, const u8 *in, int rounds);
asmlinkage void __aes_arm64_decrypt(u32 *rk, u8 *out, const u8 *in, int rounds);

struct aes_block {
	u8 b[AES_BLOCK_SIZE];
};

asmlinkage void __aes_ce_encrypt(u32 *rk, u8 *out, const u8 *in, int rounds);
asmlinkage void __aes_ce_decrypt(u32 *rk, u8 *out, const u8 *in, int rounds);

asmlinkage u32 __aes_ce_sub(u32 l);
asmlinkage void __aes_ce_invert(struct aes_block *out,
				const struct aes_block *in);

static int num_rounds(struct crypto_aes_ctx *ctx)
{
	/*
	 * # of rounds specified by AES:
	 * 128 bit key		10 rounds
	 * 192 bit key		12 rounds
	 * 256 bit key		14 rounds
	 * => n byte key	=> 6 + (n/4) rounds
	 */
	return 6 + ctx->key_length / 4;
}

static void aes_cipher_encrypt(struct crypto_tfm *tfm, u8 dst[], u8 const src[])
{
	struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);

	if (!may_use_simd()) {
		__aes_arm64_encrypt(ctx->key_enc, dst, src, num_rounds(ctx));
		return;
	}

	kernel_neon_begin();
	__aes_ce_encrypt(ctx->key_enc, dst, src, num_rounds(ctx));
	kernel_neon_end();
}

static void aes_cipher_decrypt(struct crypto_tfm *tfm, u8 dst[], u8 const src[])
{
	struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);

	if (!may_use_simd()) {
		__aes_arm64_decrypt(ctx->key_dec, dst, src, num_rounds(ctx));
		return;
	}

	kernel_neon_begin();
	__aes_ce_decrypt(ctx->key_dec, dst, src, num_rounds(ctx));
	kernel_neon_end();
}

int ce_aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,
		     unsigned int key_len)
{
	/*
	 * The AES key schedule round constants
	 */
	static u8 const rcon[] = {
		0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36,
	};

	u32 kwords = key_len / sizeof(u32);
	struct aes_block *key_enc, *key_dec;
	int i, j;

	if (key_len != AES_KEYSIZE_128 &&
	    key_len != AES_KEYSIZE_192 &&
	    key_len != AES_KEYSIZE_256)
		return -EINVAL;

	ctx->key_length = key_len;
	for (i = 0; i < kwords; i++)
		ctx->key_enc[i] = get_unaligned_le32(in_key + i * sizeof(u32));

	kernel_neon_begin();
	for (i = 0; i < sizeof(rcon); i++) {
		u32 *rki = ctx->key_enc + (i * kwords);
		u32 *rko = rki + kwords;

		rko[0] = ror32(__aes_ce_sub(rki[kwords - 1]), 8) ^ rcon[i] ^ rki[0];
		rko[1] = rko[0] ^ rki[1];
		rko[2] = rko[1] ^ rki[2];
		rko[3] = rko[2] ^ rki[3];

		if (key_len == AES_KEYSIZE_192) {
			if (i >= 7)
				break;
			rko[4] = rko[3] ^ rki[4];
			rko[5] = rko[4] ^ rki[5];
		} else if (key_len == AES_KEYSIZE_256) {
			if (i >= 6)
				break;
			rko[4] = __aes_ce_sub(rko[3]) ^ rki[4];
			rko[5] = rko[4] ^ rki[5];
			rko[6] = rko[5] ^ rki[6];
			rko[7] = rko[6] ^ rki[7];
		}
	}

	/*
	 * Generate the decryption keys for the Equivalent Inverse Cipher.
	 * This involves reversing the order of the round keys, and applying
	 * the Inverse Mix Columns transformation on all but the first and
	 * the last one.
	 */
	key_enc = (struct aes_block *)ctx->key_enc;
	key_dec = (struct aes_block *)ctx->key_dec;
	j = num_rounds(ctx);

	key_dec[0] = key_enc[j];
	for (i = 1, j--; j > 0; i++, j--)
		__aes_ce_invert(key_dec + i, key_enc + j);
	key_dec[i] = key_enc[0];

	kernel_neon_end();
	return 0;
}
EXPORT_SYMBOL(ce_aes_expandkey);

int ce_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key,
		  unsigned int key_len)
{
	struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
	int ret;

	ret = ce_aes_expandkey(ctx, in_key, key_len);
	if (!ret)
		return 0;

	tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
	return -EINVAL;
}
EXPORT_SYMBOL(ce_aes_setkey);

static struct crypto_alg aes_alg = {
	.cra_name		= "aes",
	.cra_driver_name	= "aes-ce",
	.cra_priority		= 250,
	.cra_flags		= CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize		= AES_BLOCK_SIZE,
	.cra_ctxsize		= sizeof(struct crypto_aes_ctx),
	.cra_module		= THIS_MODULE,
	.cra_cipher = {
		.cia_min_keysize	= AES_MIN_KEY_SIZE,
		.cia_max_keysize	= AES_MAX_KEY_SIZE,
		.cia_setkey		= ce_aes_setkey,
		.cia_encrypt		= aes_cipher_encrypt,
		.cia_decrypt		= aes_cipher_decrypt
	}
};

static int __init aes_mod_init(void)
{
	return crypto_register_alg(&aes_alg);
}

static void __exit aes_mod_exit(void)
{
	crypto_unregister_alg(&aes_alg);
}

module_cpu_feature_match(AES, aes_mod_init);
module_exit(aes_mod_exit);

back to top

Software Heritage — Copyright (C) 2015–2025, The Software Heritage developers. License: GNU AGPLv3+.
The source code of Software Heritage itself is available on our development forge.
The source code files archived by Software Heritage are available under their own copyright and licenses.
Terms of use: Archive access, API— Contact— JavaScript license information— Web API