From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- lib/crypto/poly1305.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 lib/crypto/poly1305.c (limited to 'lib/crypto/poly1305.c') diff --git a/lib/crypto/poly1305.c b/lib/crypto/poly1305.c new file mode 100644 index 000000000..f313ccc4b --- /dev/null +++ b/lib/crypto/poly1305.c @@ -0,0 +1,100 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Poly1305 authenticator algorithm, RFC7539 + * + * Copyright (C) 2015 Martin Willi + * + * Based on public domain code by Andrew Moon and Daniel J. Bernstein. + */ + +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_CRYPTO_LIB_POLY1305_ARCH +#include "poly1305.h" /* $(SRCARCH)/poly1305.h */ +#else +#define poly1305_block_init poly1305_block_init_generic +#define poly1305_blocks poly1305_blocks_generic +#define poly1305_emit poly1305_emit_generic +#endif + +void poly1305_init(struct poly1305_desc_ctx *desc, + const u8 key[POLY1305_KEY_SIZE]) +{ + desc->s[0] = get_unaligned_le32(key + 16); + desc->s[1] = get_unaligned_le32(key + 20); + desc->s[2] = get_unaligned_le32(key + 24); + desc->s[3] = get_unaligned_le32(key + 28); + desc->buflen = 0; + poly1305_block_init(&desc->state, key); +} +EXPORT_SYMBOL(poly1305_init); + +void poly1305_update(struct poly1305_desc_ctx *desc, + const u8 *src, unsigned int nbytes) +{ + if (desc->buflen + nbytes >= POLY1305_BLOCK_SIZE) { + unsigned int bulk_len; + + if (desc->buflen) { + unsigned int l = POLY1305_BLOCK_SIZE - desc->buflen; + + memcpy(&desc->buf[desc->buflen], src, l); + src += l; + nbytes -= l; + + poly1305_blocks(&desc->state, desc->buf, + POLY1305_BLOCK_SIZE, 1); + desc->buflen = 0; + } + + bulk_len = round_down(nbytes, POLY1305_BLOCK_SIZE); + nbytes %= POLY1305_BLOCK_SIZE; + + if (bulk_len) { + poly1305_blocks(&desc->state, src, bulk_len, 1); + src += bulk_len; + } + } + if (nbytes) { + memcpy(&desc->buf[desc->buflen], src, nbytes); + desc->buflen += nbytes; + } +} +EXPORT_SYMBOL(poly1305_update); + +void poly1305_final(struct poly1305_desc_ctx *desc, u8 *dst) +{ + if (unlikely(desc->buflen)) { + desc->buf[desc->buflen++] = 1; + memset(desc->buf + desc->buflen, 0, + POLY1305_BLOCK_SIZE - desc->buflen); + poly1305_blocks(&desc->state, desc->buf, POLY1305_BLOCK_SIZE, + 0); + } + + poly1305_emit(&desc->state.h, dst, desc->s); + *desc = (struct poly1305_desc_ctx){}; +} +EXPORT_SYMBOL(poly1305_final); + +#ifdef poly1305_mod_init_arch +static int __init poly1305_mod_init(void) +{ + poly1305_mod_init_arch(); + return 0; +} +subsys_initcall(poly1305_mod_init); + +static void __exit poly1305_mod_exit(void) +{ +} +module_exit(poly1305_mod_exit); +#endif + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Poly1305 authenticator algorithm, RFC7539"); -- cgit v1.3.1