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, 35 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.4/080-wireguard-0038-crypto-chacha-fix-warning-message-in-header-file.patch b/target/linux/generic/backport-5.4/080-wireguard-0038-crypto-chacha-fix-warning-message-in-header-file.patch
new file mode 100644
index 0000000000..6170e7b76e
--- /dev/null
+++ b/target/linux/generic/backport-5.4/080-wireguard-0038-crypto-chacha-fix-warning-message-in-header-file.patch
@@ -0,0 +1,35 @@
+From 61ad3d7b564718b9810b8112a6d2e9ad6405b167 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Valdis=20Kl=C4=93tnieks?= <valdis.kletnieks@vt.edu>
+Date: Thu, 5 Dec 2019 20:58:36 -0500
+Subject: [PATCH 038/124] crypto: chacha - fix warning message in header file
+
+commit 579d705cd64e44f3fcda1a6cfd5f37468a5ddf63 upstream.
+
+Building with W=1 causes a warning:
+
+  CC [M]  arch/x86/crypto/chacha_glue.o
+In file included from arch/x86/crypto/chacha_glue.c:10:
+./include/crypto/internal/chacha.h:37:1: warning: 'inline' is not at beginning of declaration [-Wold-style-declaration]
+   37 | static int inline chacha12_setkey(struct crypto_skcipher *tfm, const u8 *key,
+      | ^~~~~~
+
+Straighten out the order to match the rest of the header file.
+
+Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
+Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
+Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
+---
+ include/crypto/internal/chacha.h | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/include/crypto/internal/chacha.h
++++ b/include/crypto/internal/chacha.h
+@@ -34,7 +34,7 @@ static inline int chacha20_setkey(struct
+ 	return chacha_setkey(tfm, key, keysize, 20);
+ }
+ 
+-static int inline chacha12_setkey(struct crypto_skcipher *tfm, const u8 *key,
++static inline int chacha12_setkey(struct crypto_skcipher *tfm, const u8 *key,
+ 				  unsigned int keysize)
+ {
+ 	return chacha_setkey(tfm, key, keysize, 12);