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| author | Kees Cook <kees+treewide@kernel.org> | 2026-09-02 15:31:14 -0700 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2026-09-04 21:37:00 -0700 |
| commit | 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch) | |
| tree | c65086f9bdcd48c6360fb7cb4598bca084da1f32 /include/crypto/chacha.h | |
| download | linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip | |
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci
This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.
Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.
Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'include/crypto/chacha.h')
| -rw-r--r-- | include/crypto/chacha.h | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/include/crypto/chacha.h b/include/crypto/chacha.h new file mode 100644 index 000000000..1cc301a48 --- /dev/null +++ b/include/crypto/chacha.h @@ -0,0 +1,102 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Common values and helper functions for the ChaCha and XChaCha stream ciphers. + * + * XChaCha extends ChaCha's nonce to 192 bits, while provably retaining ChaCha's + * security. Here they share the same key size, tfm context, and setkey + * function; only their IV size and encrypt/decrypt function differ. + * + * The ChaCha paper specifies 20, 12, and 8-round variants. In general, it is + * recommended to use the 20-round variant ChaCha20. However, the other + * variants can be needed in some performance-sensitive scenarios. The generic + * ChaCha code currently allows only the 20 and 12-round variants. + */ + +#ifndef _CRYPTO_CHACHA_H +#define _CRYPTO_CHACHA_H + +#include <linux/unaligned.h> +#include <linux/string.h> +#include <linux/types.h> + +/* 32-bit stream position, then 96-bit nonce (RFC7539 convention) */ +#define CHACHA_IV_SIZE 16 + +#define CHACHA_KEY_SIZE 32 +#define CHACHA_BLOCK_SIZE 64 +#define CHACHAPOLY_IV_SIZE 12 + +#define CHACHA_KEY_WORDS 8 +#define CHACHA_STATE_WORDS 16 +#define HCHACHA_OUT_WORDS 8 + +/* 192-bit nonce, then 64-bit stream position */ +#define XCHACHA_IV_SIZE 32 + +struct chacha_state { + u32 x[CHACHA_STATE_WORDS]; +}; + +void chacha_block_generic(struct chacha_state *state, + u8 out[at_least CHACHA_BLOCK_SIZE], int nrounds); +static inline void chacha20_block(struct chacha_state *state, + u8 out[at_least CHACHA_BLOCK_SIZE]) +{ + chacha_block_generic(state, out, 20); +} + +void hchacha_block_generic(const struct chacha_state *state, + u32 out[at_least HCHACHA_OUT_WORDS], int nrounds); + +void hchacha_block(const struct chacha_state *state, + u32 out[at_least HCHACHA_OUT_WORDS], int nrounds); + +enum chacha_constants { /* expand 32-byte k */ + CHACHA_CONSTANT_EXPA = 0x61707865U, + CHACHA_CONSTANT_ND_3 = 0x3320646eU, + CHACHA_CONSTANT_2_BY = 0x79622d32U, + CHACHA_CONSTANT_TE_K = 0x6b206574U +}; + +static inline void chacha_init_consts(struct chacha_state *state) +{ + state->x[0] = CHACHA_CONSTANT_EXPA; + state->x[1] = CHACHA_CONSTANT_ND_3; + state->x[2] = CHACHA_CONSTANT_2_BY; + state->x[3] = CHACHA_CONSTANT_TE_K; +} + +static inline void chacha_init(struct chacha_state *state, + const u32 key[at_least CHACHA_KEY_WORDS], + const u8 iv[at_least CHACHA_IV_SIZE]) +{ + chacha_init_consts(state); + state->x[4] = key[0]; + state->x[5] = key[1]; + state->x[6] = key[2]; + state->x[7] = key[3]; + state->x[8] = key[4]; + state->x[9] = key[5]; + state->x[10] = key[6]; + state->x[11] = key[7]; + state->x[12] = get_unaligned_le32(iv + 0); + state->x[13] = get_unaligned_le32(iv + 4); + state->x[14] = get_unaligned_le32(iv + 8); + state->x[15] = get_unaligned_le32(iv + 12); +} + +void chacha_crypt(struct chacha_state *state, u8 *dst, const u8 *src, + unsigned int bytes, int nrounds); + +static inline void chacha20_crypt(struct chacha_state *state, + u8 *dst, const u8 *src, unsigned int bytes) +{ + chacha_crypt(state, dst, src, bytes, 20); +} + +static inline void chacha_zeroize_state(struct chacha_state *state) +{ + memzero_explicit(state, sizeof(*state)); +} + +#endif /* _CRYPTO_CHACHA_H */ |
