kernel: 5.4: import wireguard backport

Rather than using the clunky, old, slower wireguard-linux-compat out of
tree module, this commit does a patch-by-patch backport of upstream's
wireguard to 5.4. This specific backport is in widespread use, being
part of SUSE's enterprise kernel, Oracle's enterprise kernel, Google's
Android kernel, Gentoo's distro kernel, and probably more I've forgotten
about. It's definately the "more proper" way of adding wireguard to a
kernel than the ugly compat.h hell of the wireguard-linux-compat repo.
And most importantly for OpenWRT, it allows using the same module
configuration code for 5.10 as for 5.4, with no need for bifurcation.

These patches are from the backport tree which is maintained in the
open here: https://git.zx2c4.com/wireguard-linux/log/?h=backport-5.4.y
I'll be sending PRs to update this as needed.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 245 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.4/080-wireguard-0023-crypto-blake2s-implement-generic-shash-driver.patch b/target/linux/generic/backport-5.4/080-wireguard-0023-crypto-blake2s-implement-generic-shash-driver.patch
new file mode 100644
index 0000000000..4116973631
--- /dev/null
+++ b/target/linux/generic/backport-5.4/080-wireguard-0023-crypto-blake2s-implement-generic-shash-driver.patch
@@ -0,0 +1,245 @@
+From af5b936f5e17306da571f703bdef1f011a602b57 Mon Sep 17 00:00:00 2001
+From: Ard Biesheuvel <ardb@kernel.org>
+Date: Fri, 8 Nov 2019 13:22:30 +0100
+Subject: [PATCH 023/124] crypto: blake2s - implement generic shash driver
+
+commit 7f9b0880925f1f9d7d59504ea0892d2ae9cfc233 upstream.
+
+Wire up our newly added Blake2s implementation via the shash API.
+
+Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
+Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
+Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
+---
+ crypto/Kconfig                    |  18 ++++
+ crypto/Makefile                   |   1 +
+ crypto/blake2s_generic.c          | 171 ++++++++++++++++++++++++++++++
+ include/crypto/internal/blake2s.h |   5 +
+ 4 files changed, 195 insertions(+)
+ create mode 100644 crypto/blake2s_generic.c
+
+--- a/crypto/Kconfig
++++ b/crypto/Kconfig
+@@ -639,6 +639,24 @@ config CRYPTO_XXHASH
+ 	  xxHash non-cryptographic hash algorithm. Extremely fast, working at
+ 	  speeds close to RAM limits.
+ 
++config CRYPTO_BLAKE2S
++	tristate "BLAKE2s digest algorithm"
++	select CRYPTO_LIB_BLAKE2S_GENERIC
++	select CRYPTO_HASH
++	help
++	  Implementation of cryptographic hash function BLAKE2s
++	  optimized for 8-32bit platforms and can produce digests of any size
++	  between 1 to 32.  The keyed hash is also implemented.
++
++	  This module provides the following algorithms:
++
++	  - blake2s-128
++	  - blake2s-160
++	  - blake2s-224
++	  - blake2s-256
++
++	  See https://blake2.net for further information.
++
+ config CRYPTO_CRCT10DIF
+ 	tristate "CRCT10DIF algorithm"
+ 	select CRYPTO_HASH
+--- a/crypto/Makefile
++++ b/crypto/Makefile
+@@ -74,6 +74,7 @@ obj-$(CONFIG_CRYPTO_STREEBOG) += streebo
+ obj-$(CONFIG_CRYPTO_WP512) += wp512.o
+ CFLAGS_wp512.o := $(call cc-option,-fno-schedule-insns)  # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79149
+ obj-$(CONFIG_CRYPTO_TGR192) += tgr192.o
++obj-$(CONFIG_CRYPTO_BLAKE2S) += blake2s_generic.o
+ obj-$(CONFIG_CRYPTO_GF128MUL) += gf128mul.o
+ obj-$(CONFIG_CRYPTO_ECB) += ecb.o
+ obj-$(CONFIG_CRYPTO_CBC) += cbc.o
+--- /dev/null
++++ b/crypto/blake2s_generic.c
+@@ -0,0 +1,171 @@
++// SPDX-License-Identifier: GPL-2.0 OR MIT
++/*
++ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
++ */
++
++#include <crypto/internal/blake2s.h>
++#include <crypto/internal/simd.h>
++#include <crypto/internal/hash.h>
++
++#include <linux/types.h>
++#include <linux/jump_label.h>
++#include <linux/kernel.h>
++#include <linux/module.h>
++
++static int crypto_blake2s_setkey(struct crypto_shash *tfm, const u8 *key,
++				 unsigned int keylen)
++{
++	struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(tfm);
++
++	if (keylen == 0 || keylen > BLAKE2S_KEY_SIZE) {
++		crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
++		return -EINVAL;
++	}
++
++	memcpy(tctx->key, key, keylen);
++	tctx->keylen = keylen;
++
++	return 0;
++}
++
++static int crypto_blake2s_init(struct shash_desc *desc)
++{
++	struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
++	struct blake2s_state *state = shash_desc_ctx(desc);
++	const int outlen = crypto_shash_digestsize(desc->tfm);
++
++	if (tctx->keylen)
++		blake2s_init_key(state, outlen, tctx->key, tctx->keylen);
++	else
++		blake2s_init(state, outlen);
++
++	return 0;
++}
++
++static int crypto_blake2s_update(struct shash_desc *desc, const u8 *in,
++				 unsigned int inlen)
++{
++	struct blake2s_state *state = shash_desc_ctx(desc);
++	const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen;
++
++	if (unlikely(!inlen))
++		return 0;
++	if (inlen > fill) {
++		memcpy(state->buf + state->buflen, in, fill);
++		blake2s_compress_generic(state, state->buf, 1, BLAKE2S_BLOCK_SIZE);
++		state->buflen = 0;
++		in += fill;
++		inlen -= fill;
++	}
++	if (inlen > BLAKE2S_BLOCK_SIZE) {
++		const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE);
++		/* Hash one less (full) block than strictly possible */
++		blake2s_compress_generic(state, in, nblocks - 1, BLAKE2S_BLOCK_SIZE);
++		in += BLAKE2S_BLOCK_SIZE * (nblocks - 1);
++		inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1);
++	}
++	memcpy(state->buf + state->buflen, in, inlen);
++	state->buflen += inlen;
++
++	return 0;
++}
++
++static int crypto_blake2s_final(struct shash_desc *desc, u8 *out)
++{
++	struct blake2s_state *state = shash_desc_ctx(desc);
++
++	blake2s_set_lastblock(state);
++	memset(state->buf + state->buflen, 0,
++	       BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */
++	blake2s_compress_generic(state, state->buf, 1, state->buflen);
++	cpu_to_le32_array(state->h, ARRAY_SIZE(state->h));
++	memcpy(out, state->h, state->outlen);
++	memzero_explicit(state, sizeof(*state));
++
++	return 0;
++}
++
++static struct shash_alg blake2s_algs[] = {{
++	.base.cra_name		= "blake2s-128",
++	.base.cra_driver_name	= "blake2s-128-generic",
++	.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
++	.base.cra_ctxsize	= sizeof(struct blake2s_tfm_ctx),
++	.base.cra_priority	= 200,
++	.base.cra_blocksize     = BLAKE2S_BLOCK_SIZE,
++	.base.cra_module	= THIS_MODULE,
++
++	.digestsize		= BLAKE2S_128_HASH_SIZE,
++	.setkey			= crypto_blake2s_setkey,
++	.init			= crypto_blake2s_init,
++	.update			= crypto_blake2s_update,
++	.final			= crypto_blake2s_final,
++	.descsize		= sizeof(struct blake2s_state),
++}, {
++	.base.cra_name		= "blake2s-160",
++	.base.cra_driver_name	= "blake2s-160-generic",
++	.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
++	.base.cra_ctxsize	= sizeof(struct blake2s_tfm_ctx),
++	.base.cra_priority	= 200,
++	.base.cra_blocksize     = BLAKE2S_BLOCK_SIZE,
++	.base.cra_module	= THIS_MODULE,
++
++	.digestsize		= BLAKE2S_160_HASH_SIZE,
++	.setkey			= crypto_blake2s_setkey,
++	.init			= crypto_blake2s_init,
++	.update			= crypto_blake2s_update,
++	.final			= crypto_blake2s_final,
++	.descsize		= sizeof(struct blake2s_state),
++}, {
++	.base.cra_name		= "blake2s-224",
++	.base.cra_driver_name	= "blake2s-224-generic",
++	.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
++	.base.cra_ctxsize	= sizeof(struct blake2s_tfm_ctx),
++	.base.cra_priority	= 200,
++	.base.cra_blocksize     = BLAKE2S_BLOCK_SIZE,
++	.base.cra_module	= THIS_MODULE,
++
++	.digestsize		= BLAKE2S_224_HASH_SIZE,
++	.setkey			= crypto_blake2s_setkey,
++	.init			= crypto_blake2s_init,
++	.update			= crypto_blake2s_update,
++	.final			= crypto_blake2s_final,
++	.descsize		= sizeof(struct blake2s_state),
++}, {
++	.base.cra_name		= "blake2s-256",
++	.base.cra_driver_name	= "blake2s-256-generic",
++	.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
++	.base.cra_ctxsize	= sizeof(struct blake2s_tfm_ctx),
++	.base.cra_priority	= 200,
++	.base.cra_blocksize     = BLAKE2S_BLOCK_SIZE,
++	.base.cra_module	= THIS_MODULE,
++
++	.digestsize		= BLAKE2S_256_HASH_SIZE,
++	.setkey			= crypto_blake2s_setkey,
++	.init			= crypto_blake2s_init,
++	.update			= crypto_blake2s_update,
++	.final			= crypto_blake2s_final,
++	.descsize		= sizeof(struct blake2s_state),
++}};
++
++static int __init blake2s_mod_init(void)
++{
++	return crypto_register_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs));
++}
++
++static void __exit blake2s_mod_exit(void)
++{
++	crypto_unregister_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs));
++}
++
++subsys_initcall(blake2s_mod_init);
++module_exit(blake2s_mod_exit);
++
++MODULE_ALIAS_CRYPTO("blake2s-128");
++MODULE_ALIAS_CRYPTO("blake2s-128-generic");
++MODULE_ALIAS_CRYPTO("blake2s-160");
++MODULE_ALIAS_CRYPTO("blake2s-160-generic");
++MODULE_ALIAS_CRYPTO("blake2s-224");
++MODULE_ALIAS_CRYPTO("blake2s-224-generic");
++MODULE_ALIAS_CRYPTO("blake2s-256");
++MODULE_ALIAS_CRYPTO("blake2s-256-generic");
++MODULE_LICENSE("GPL v2");
+--- a/include/crypto/internal/blake2s.h
++++ b/include/crypto/internal/blake2s.h
+@@ -5,6 +5,11 @@
+ 
+ #include <crypto/blake2s.h>
+ 
++struct blake2s_tfm_ctx {
++	u8 key[BLAKE2S_KEY_SIZE];
++	unsigned int keylen;
++};
++
+ void blake2s_compress_generic(struct blake2s_state *state,const u8 *block,
+ 			      size_t nblocks, const u32 inc);
+