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192.168.1.100 / T108 / c2023d5d03be91dbb983606f0ec5e9e4ea36c8c2 / . / target / linux / generic / backport-5.4 / 080-wireguard-0005-crypto-arm64-chacha-depend-on-generic-chacha-library.patch
blob: e12e9d115397d05cde748461ca4ebfb8477652ac [file] [log] [blame]
b.liue9582032025-04-17 19:18:16 +0800[diff] [blame]1From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
2From: Ard Biesheuvel <ardb@kernel.org>
3Date: Fri, 8 Nov 2019 13:22:11 +0100
4Subject: [PATCH] crypto: arm64/chacha - depend on generic chacha library
5 instead of crypto driver
6
7commit c77da4867cbb7841177275dbb250f5c09679fae4 upstream.
8
9Depend on the generic ChaCha library routines instead of pulling in the
10generic ChaCha skcipher driver, which is more than we need, and makes
11managing the dependencies between the generic library, generic driver,
12accelerated library and driver more complicated.
13
14While at it, drop the logic to prefer the scalar code on short inputs.
15Turning the NEON on and off is cheap these days, and one major use case
16for ChaCha20 is ChaCha20-Poly1305, which is guaranteed to hit the scalar
17path upon every invocation (when doing the Poly1305 nonce generation)
18
19Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
20Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
21Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
22---
23 arch/arm64/crypto/Kconfig | 2 +-
24 arch/arm64/crypto/chacha-neon-glue.c | 40 +++++++++++++++-------------
25 2 files changed, 23 insertions(+), 19 deletions(-)
26
27--- a/arch/arm64/crypto/Kconfig
28+++ b/arch/arm64/crypto/Kconfig
29@@ -104,7 +104,7 @@ config CRYPTO_CHACHA20_NEON
30 tristate "ChaCha20, XChaCha20, and XChaCha12 stream ciphers using NEON instructions"
31 depends on KERNEL_MODE_NEON
32 select CRYPTO_BLKCIPHER
33- select CRYPTO_CHACHA20
34+ select CRYPTO_LIB_CHACHA_GENERIC
35
36 config CRYPTO_NHPOLY1305_NEON
37 tristate "NHPoly1305 hash function using NEON instructions (for Adiantum)"
38--- a/arch/arm64/crypto/chacha-neon-glue.c
39+++ b/arch/arm64/crypto/chacha-neon-glue.c
40@@ -68,7 +68,7 @@ static int chacha_neon_stream_xor(struct
41
42 err = skcipher_walk_virt(&walk, req, false);
43
44- crypto_chacha_init(state, ctx, iv);
45+ chacha_init_generic(state, ctx->key, iv);
46
47 while (walk.nbytes > 0) {
48 unsigned int nbytes = walk.nbytes;
49@@ -76,10 +76,16 @@ static int chacha_neon_stream_xor(struct
50 if (nbytes < walk.total)
51 nbytes = rounddown(nbytes, walk.stride);
52
53- kernel_neon_begin();
54- chacha_doneon(state, walk.dst.virt.addr, walk.src.virt.addr,
55- nbytes, ctx->nrounds);
56- kernel_neon_end();
57+ if (!crypto_simd_usable()) {
58+ chacha_crypt_generic(state, walk.dst.virt.addr,
59+ walk.src.virt.addr, nbytes,
60+ ctx->nrounds);
61+ } else {
62+ kernel_neon_begin();
63+ chacha_doneon(state, walk.dst.virt.addr,
64+ walk.src.virt.addr, nbytes, ctx->nrounds);
65+ kernel_neon_end();
66+ }
67 err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
68 }
69
70@@ -91,9 +97,6 @@ static int chacha_neon(struct skcipher_r
71 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
72 struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
73
74- if (req->cryptlen <= CHACHA_BLOCK_SIZE || !crypto_simd_usable())
75- return crypto_chacha_crypt(req);
76-
77 return chacha_neon_stream_xor(req, ctx, req->iv);
78 }
79
80@@ -105,14 +108,15 @@ static int xchacha_neon(struct skcipher_
81 u32 state[16];
82 u8 real_iv[16];
83
84- if (req->cryptlen <= CHACHA_BLOCK_SIZE || !crypto_simd_usable())
85- return crypto_xchacha_crypt(req);
86-
87- crypto_chacha_init(state, ctx, req->iv);
88+ chacha_init_generic(state, ctx->key, req->iv);
89
90- kernel_neon_begin();
91- hchacha_block_neon(state, subctx.key, ctx->nrounds);
92- kernel_neon_end();
93+ if (crypto_simd_usable()) {
94+ kernel_neon_begin();
95+ hchacha_block_neon(state, subctx.key, ctx->nrounds);
96+ kernel_neon_end();
97+ } else {
98+ hchacha_block_generic(state, subctx.key, ctx->nrounds);
99+ }
100 subctx.nrounds = ctx->nrounds;
101
102 memcpy(&real_iv[0], req->iv + 24, 8);
103@@ -134,7 +138,7 @@ static struct skcipher_alg algs[] = {
104 .ivsize = CHACHA_IV_SIZE,
105 .chunksize = CHACHA_BLOCK_SIZE,
106 .walksize = 5 * CHACHA_BLOCK_SIZE,
107- .setkey = crypto_chacha20_setkey,
108+ .setkey = chacha20_setkey,
109 .encrypt = chacha_neon,
110 .decrypt = chacha_neon,
111 }, {
112@@ -150,7 +154,7 @@ static struct skcipher_alg algs[] = {
113 .ivsize = XCHACHA_IV_SIZE,
114 .chunksize = CHACHA_BLOCK_SIZE,
115 .walksize = 5 * CHACHA_BLOCK_SIZE,
116- .setkey = crypto_chacha20_setkey,
117+ .setkey = chacha20_setkey,
118 .encrypt = xchacha_neon,
119 .decrypt = xchacha_neon,
120 }, {
121@@ -166,7 +170,7 @@ static struct skcipher_alg algs[] = {
122 .ivsize = XCHACHA_IV_SIZE,
123 .chunksize = CHACHA_BLOCK_SIZE,
124 .walksize = 5 * CHACHA_BLOCK_SIZE,
125- .setkey = crypto_chacha12_setkey,
126+ .setkey = chacha12_setkey,
127 .encrypt = xchacha_neon,
128 .decrypt = xchacha_neon,
129 }