In preparation for adding XChaCha12 support, rename/refactor
chacha20-generic to support different numbers of rounds. The
justification for needing XChaCha12 support is explained in more detail
in the patch "crypto: chacha - add XChaCha12 support".
The only difference between ChaCha{8,12,20} are the number of rounds
itself; all other parts of the algorithm are the same. Therefore,
remove the "20" from all definitions, structures, functions, files, etc.
that will be shared by all ChaCha versions.
Also make ->setkey() store the round count in the chacha_ctx (previously
chacha20_ctx). The generic code then passes the round count through to
chacha_block(). There will be a ->setkey() function for each explicitly
allowed round count; the encrypt/decrypt functions will be the same. I
decided not to do it the opposite way (same ->setkey() function for all
round counts, with different encrypt/decrypt functions) because that
would have required more boilerplate code in architecture-specific
implementations of ChaCha and XChaCha.
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 1ca1b917940c24ca3d1f490118c5474168622953
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master)
Conflicts:
arch/arm64/crypto/chacha20-neon-glue.c
arch/x86/crypto/chacha20_glue.c
drivers/crypto/caam/caamalg.c
drivers/crypto/caam/caamalg_qi2.c
drivers/crypto/caam/compat.h
include/crypto/chacha20.h
Bug: 112008522
Test: As series, see Ic61c13b53facfd2173065be715a7ee5f3af8760b
Change-Id: I7fa203ddc7095ce8675a32f49b8a5230cd0cf5f6
Signed-off-by: Eric Biggers <ebiggers@google.com>
tirimbino
Eric Biggers
6 years ago
parent
5fad54249f
commit
fd5e6015bc
@ -0,0 +1,46 @@ |
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/* SPDX-License-Identifier: GPL-2.0 */ |
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/*
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* Common values and helper functions for the ChaCha and XChaCha stream ciphers. |
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* |
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* XChaCha extends ChaCha's nonce to 192 bits, while provably retaining ChaCha's |
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* security. Here they share the same key size, tfm context, and setkey |
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* function; only their IV size and encrypt/decrypt function differ. |
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*/ |
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#ifndef _CRYPTO_CHACHA_H |
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#define _CRYPTO_CHACHA_H |
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#include <crypto/skcipher.h> |
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#include <linux/types.h> |
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#include <linux/crypto.h> |
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/* 32-bit stream position, then 96-bit nonce (RFC7539 convention) */ |
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#define CHACHA_IV_SIZE 16 |
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#define CHACHA_KEY_SIZE 32 |
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#define CHACHA_BLOCK_SIZE 64 |
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/* 192-bit nonce, then 64-bit stream position */ |
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#define XCHACHA_IV_SIZE 32 |
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struct chacha_ctx { |
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u32 key[8]; |
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int nrounds; |
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}; |
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void chacha_block(u32 *state, u8 *stream, int nrounds); |
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static inline void chacha20_block(u32 *state, u8 *stream) |
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{ |
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chacha_block(state, stream, 20); |
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} |
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void hchacha_block(const u32 *in, u32 *out, int nrounds); |
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void crypto_chacha_init(u32 *state, struct chacha_ctx *ctx, u8 *iv); |
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int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, |
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unsigned int keysize); |
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int crypto_chacha_crypt(struct skcipher_request *req); |
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int crypto_xchacha_crypt(struct skcipher_request *req); |
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#endif /* _CRYPTO_CHACHA_H */ |
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@ -1,41 +0,0 @@ |
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/* SPDX-License-Identifier: GPL-2.0 */ |
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/*
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* Common values and helper functions for the ChaCha20 and XChaCha20 algorithms. |
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* |
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* XChaCha20 extends ChaCha20's nonce to 192 bits, while provably retaining |
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* ChaCha20's security. Here they share the same key size, tfm context, and |
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* setkey function; only their IV size and encrypt/decrypt function differ. |
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*/ |
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#ifndef _CRYPTO_CHACHA20_H |
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#define _CRYPTO_CHACHA20_H |
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#include <crypto/skcipher.h> |
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#include <linux/types.h> |
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#include <linux/crypto.h> |
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/* 32-bit stream position, then 96-bit nonce (RFC7539 convention) */ |
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#define CHACHA20_IV_SIZE 16 |
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#define CHACHA20_KEY_SIZE 32 |
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#define CHACHA20_BLOCK_SIZE 64 |
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/* 192-bit nonce, then 64-bit stream position */ |
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#define XCHACHA20_IV_SIZE 32 |
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struct chacha20_ctx { |
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u32 key[8]; |
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}; |
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void chacha20_block(u32 *state, u8 *stream); |
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void hchacha20_block(const u32 *in, u32 *out); |
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void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv); |
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int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, |
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unsigned int keysize); |
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int crypto_chacha20_crypt(struct skcipher_request *req); |
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int crypto_xchacha20_crypt(struct skcipher_request *req); |
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#endif |
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