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, 275 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.4/080-wireguard-0037-crypto-arch-conditionalize-crypto-api-in-arch-glue-f.patch b/target/linux/generic/backport-5.4/080-wireguard-0037-crypto-arch-conditionalize-crypto-api-in-arch-glue-f.patch
new file mode 100644
index 0000000000..ab04cecf05
--- /dev/null
+++ b/target/linux/generic/backport-5.4/080-wireguard-0037-crypto-arch-conditionalize-crypto-api-in-arch-glue-f.patch
@@ -0,0 +1,275 @@
+From f23fdc58a0a08afada84fe4910279ec3d8d085e7 Mon Sep 17 00:00:00 2001
+From: "Jason A. Donenfeld" <Jason@zx2c4.com>
+Date: Mon, 25 Nov 2019 11:31:12 +0100
+Subject: [PATCH 037/124] crypto: arch - conditionalize crypto api in arch glue
+ for lib code
+
+commit 8394bfec51e0e565556101bcc4e2fe7551104cd8 upstream.
+
+For glue code that's used by Zinc, the actual Crypto API functions might
+not necessarily exist, and don't need to exist either. Before this
+patch, there are valid build configurations that lead to a unbuildable
+kernel. This fixes it to conditionalize those symbols on the existence
+of the proper config entry.
+
+Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
+Acked-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>
+---
+ arch/arm/crypto/chacha-glue.c        | 26 ++++++++++++++++----------
+ arch/arm/crypto/curve25519-glue.c    |  5 +++--
+ arch/arm/crypto/poly1305-glue.c      |  9 ++++++---
+ arch/arm64/crypto/chacha-neon-glue.c |  5 +++--
+ arch/arm64/crypto/poly1305-glue.c    |  5 +++--
+ arch/mips/crypto/chacha-glue.c       |  6 ++++--
+ arch/mips/crypto/poly1305-glue.c     |  6 ++++--
+ arch/x86/crypto/blake2s-glue.c       |  6 ++++--
+ arch/x86/crypto/chacha_glue.c        |  5 +++--
+ arch/x86/crypto/curve25519-x86_64.c  |  7 ++++---
+ arch/x86/crypto/poly1305_glue.c      |  5 +++--
+ 11 files changed, 53 insertions(+), 32 deletions(-)
+
+--- a/arch/arm/crypto/chacha-glue.c
++++ b/arch/arm/crypto/chacha-glue.c
+@@ -286,11 +286,13 @@ static struct skcipher_alg neon_algs[] =
+ 
+ static int __init chacha_simd_mod_init(void)
+ {
+-	int err;
++	int err = 0;
+ 
+-	err = crypto_register_skciphers(arm_algs, ARRAY_SIZE(arm_algs));
+-	if (err)
+-		return err;
++	if (IS_REACHABLE(CONFIG_CRYPTO_BLKCIPHER)) {
++		err = crypto_register_skciphers(arm_algs, ARRAY_SIZE(arm_algs));
++		if (err)
++			return err;
++	}
+ 
+ 	if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && (elf_hwcap & HWCAP_NEON)) {
+ 		int i;
+@@ -310,18 +312,22 @@ static int __init chacha_simd_mod_init(v
+ 			static_branch_enable(&use_neon);
+ 		}
+ 
+-		err = crypto_register_skciphers(neon_algs, ARRAY_SIZE(neon_algs));
+-		if (err)
+-			crypto_unregister_skciphers(arm_algs, ARRAY_SIZE(arm_algs));
++		if (IS_REACHABLE(CONFIG_CRYPTO_BLKCIPHER)) {
++			err = crypto_register_skciphers(neon_algs, ARRAY_SIZE(neon_algs));
++			if (err)
++				crypto_unregister_skciphers(arm_algs, ARRAY_SIZE(arm_algs));
++		}
+ 	}
+ 	return err;
+ }
+ 
+ static void __exit chacha_simd_mod_fini(void)
+ {
+-	crypto_unregister_skciphers(arm_algs, ARRAY_SIZE(arm_algs));
+-	if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && (elf_hwcap & HWCAP_NEON))
+-		crypto_unregister_skciphers(neon_algs, ARRAY_SIZE(neon_algs));
++	if (IS_REACHABLE(CONFIG_CRYPTO_BLKCIPHER)) {
++		crypto_unregister_skciphers(arm_algs, ARRAY_SIZE(arm_algs));
++		if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && (elf_hwcap & HWCAP_NEON))
++			crypto_unregister_skciphers(neon_algs, ARRAY_SIZE(neon_algs));
++	}
+ }
+ 
+ module_init(chacha_simd_mod_init);
+--- a/arch/arm/crypto/curve25519-glue.c
++++ b/arch/arm/crypto/curve25519-glue.c
+@@ -108,14 +108,15 @@ static int __init mod_init(void)
+ {
+ 	if (elf_hwcap & HWCAP_NEON) {
+ 		static_branch_enable(&have_neon);
+-		return crypto_register_kpp(&curve25519_alg);
++		return IS_REACHABLE(CONFIG_CRYPTO_KPP) ?
++			crypto_register_kpp(&curve25519_alg) : 0;
+ 	}
+ 	return 0;
+ }
+ 
+ static void __exit mod_exit(void)
+ {
+-	if (elf_hwcap & HWCAP_NEON)
++	if (IS_REACHABLE(CONFIG_CRYPTO_KPP) && elf_hwcap & HWCAP_NEON)
+ 		crypto_unregister_kpp(&curve25519_alg);
+ }
+ 
+--- a/arch/arm/crypto/poly1305-glue.c
++++ b/arch/arm/crypto/poly1305-glue.c
+@@ -249,16 +249,19 @@ static int __init arm_poly1305_mod_init(
+ 	if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) &&
+ 	    (elf_hwcap & HWCAP_NEON))
+ 		static_branch_enable(&have_neon);
+-	else
++	else if (IS_REACHABLE(CONFIG_CRYPTO_HASH))
+ 		/* register only the first entry */
+ 		return crypto_register_shash(&arm_poly1305_algs[0]);
+ 
+-	return crypto_register_shashes(arm_poly1305_algs,
+-				       ARRAY_SIZE(arm_poly1305_algs));
++	return IS_REACHABLE(CONFIG_CRYPTO_HASH) ?
++		crypto_register_shashes(arm_poly1305_algs,
++					ARRAY_SIZE(arm_poly1305_algs)) : 0;
+ }
+ 
+ static void __exit arm_poly1305_mod_exit(void)
+ {
++	if (!IS_REACHABLE(CONFIG_CRYPTO_HASH))
++		return;
+ 	if (!static_branch_likely(&have_neon)) {
+ 		crypto_unregister_shash(&arm_poly1305_algs[0]);
+ 		return;
+--- a/arch/arm64/crypto/chacha-neon-glue.c
++++ b/arch/arm64/crypto/chacha-neon-glue.c
+@@ -211,12 +211,13 @@ static int __init chacha_simd_mod_init(v
+ 
+ 	static_branch_enable(&have_neon);
+ 
+-	return crypto_register_skciphers(algs, ARRAY_SIZE(algs));
++	return IS_REACHABLE(CONFIG_CRYPTO_BLKCIPHER) ?
++		crypto_register_skciphers(algs, ARRAY_SIZE(algs)) : 0;
+ }
+ 
+ static void __exit chacha_simd_mod_fini(void)
+ {
+-	if (cpu_have_named_feature(ASIMD))
++	if (IS_REACHABLE(CONFIG_CRYPTO_BLKCIPHER) && cpu_have_named_feature(ASIMD))
+ 		crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
+ }
+ 
+--- a/arch/arm64/crypto/poly1305-glue.c
++++ b/arch/arm64/crypto/poly1305-glue.c
+@@ -220,12 +220,13 @@ static int __init neon_poly1305_mod_init
+ 
+ 	static_branch_enable(&have_neon);
+ 
+-	return crypto_register_shash(&neon_poly1305_alg);
++	return IS_REACHABLE(CONFIG_CRYPTO_HASH) ?
++		crypto_register_shash(&neon_poly1305_alg) : 0;
+ }
+ 
+ static void __exit neon_poly1305_mod_exit(void)
+ {
+-	if (cpu_have_named_feature(ASIMD))
++	if (IS_REACHABLE(CONFIG_CRYPTO_HASH) && cpu_have_named_feature(ASIMD))
+ 		crypto_unregister_shash(&neon_poly1305_alg);
+ }
+ 
+--- a/arch/mips/crypto/chacha-glue.c
++++ b/arch/mips/crypto/chacha-glue.c
+@@ -128,12 +128,14 @@ static struct skcipher_alg algs[] = {
+ 
+ static int __init chacha_simd_mod_init(void)
+ {
+-	return crypto_register_skciphers(algs, ARRAY_SIZE(algs));
++	return IS_REACHABLE(CONFIG_CRYPTO_BLKCIPHER) ?
++		crypto_register_skciphers(algs, ARRAY_SIZE(algs)) : 0;
+ }
+ 
+ static void __exit chacha_simd_mod_fini(void)
+ {
+-	crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
++	if (IS_REACHABLE(CONFIG_CRYPTO_BLKCIPHER))
++		crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
+ }
+ 
+ module_init(chacha_simd_mod_init);
+--- a/arch/mips/crypto/poly1305-glue.c
++++ b/arch/mips/crypto/poly1305-glue.c
+@@ -187,12 +187,14 @@ static struct shash_alg mips_poly1305_al
+ 
+ static int __init mips_poly1305_mod_init(void)
+ {
+-	return crypto_register_shash(&mips_poly1305_alg);
++	return IS_REACHABLE(CONFIG_CRYPTO_HASH) ?
++		crypto_register_shash(&mips_poly1305_alg) : 0;
+ }
+ 
+ static void __exit mips_poly1305_mod_exit(void)
+ {
+-	crypto_unregister_shash(&mips_poly1305_alg);
++	if (IS_REACHABLE(CONFIG_CRYPTO_HASH))
++		crypto_unregister_shash(&mips_poly1305_alg);
+ }
+ 
+ module_init(mips_poly1305_mod_init);
+--- a/arch/x86/crypto/blake2s-glue.c
++++ b/arch/x86/crypto/blake2s-glue.c
+@@ -210,12 +210,14 @@ static int __init blake2s_mod_init(void)
+ 			      XFEATURE_MASK_AVX512, NULL))
+ 		static_branch_enable(&blake2s_use_avx512);
+ 
+-	return crypto_register_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs));
++	return IS_REACHABLE(CONFIG_CRYPTO_HASH) ?
++		crypto_register_shashes(blake2s_algs,
++					ARRAY_SIZE(blake2s_algs)) : 0;
+ }
+ 
+ static void __exit blake2s_mod_exit(void)
+ {
+-	if (boot_cpu_has(X86_FEATURE_SSSE3))
++	if (IS_REACHABLE(CONFIG_CRYPTO_HASH) && boot_cpu_has(X86_FEATURE_SSSE3))
+ 		crypto_unregister_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs));
+ }
+ 
+--- a/arch/x86/crypto/chacha_glue.c
++++ b/arch/x86/crypto/chacha_glue.c
+@@ -299,12 +299,13 @@ static int __init chacha_simd_mod_init(v
+ 		    boot_cpu_has(X86_FEATURE_AVX512BW)) /* kmovq */
+ 			static_branch_enable(&chacha_use_avx512vl);
+ 	}
+-	return crypto_register_skciphers(algs, ARRAY_SIZE(algs));
++	return IS_REACHABLE(CONFIG_CRYPTO_BLKCIPHER) ?
++		crypto_register_skciphers(algs, ARRAY_SIZE(algs)) : 0;
+ }
+ 
+ static void __exit chacha_simd_mod_fini(void)
+ {
+-	if (boot_cpu_has(X86_FEATURE_SSSE3))
++	if (IS_REACHABLE(CONFIG_CRYPTO_BLKCIPHER) && boot_cpu_has(X86_FEATURE_SSSE3))
+ 		crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
+ }
+ 
+--- a/arch/x86/crypto/curve25519-x86_64.c
++++ b/arch/x86/crypto/curve25519-x86_64.c
+@@ -2457,13 +2457,14 @@ static int __init curve25519_mod_init(vo
+ 		static_branch_enable(&curve25519_use_adx);
+ 	else
+ 		return 0;
+-	return crypto_register_kpp(&curve25519_alg);
++	return IS_REACHABLE(CONFIG_CRYPTO_KPP) ?
++		crypto_register_kpp(&curve25519_alg) : 0;
+ }
+ 
+ static void __exit curve25519_mod_exit(void)
+ {
+-	if (boot_cpu_has(X86_FEATURE_BMI2) ||
+-	    boot_cpu_has(X86_FEATURE_ADX))
++	if (IS_REACHABLE(CONFIG_CRYPTO_KPP) &&
++	    (boot_cpu_has(X86_FEATURE_BMI2) || boot_cpu_has(X86_FEATURE_ADX)))
+ 		crypto_unregister_kpp(&curve25519_alg);
+ }
+ 
+--- a/arch/x86/crypto/poly1305_glue.c
++++ b/arch/x86/crypto/poly1305_glue.c
+@@ -224,12 +224,13 @@ static int __init poly1305_simd_mod_init
+ 	    cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, NULL))
+ 		static_branch_enable(&poly1305_use_avx2);
+ 
+-	return crypto_register_shash(&alg);
++	return IS_REACHABLE(CONFIG_CRYPTO_HASH) ? crypto_register_shash(&alg) : 0;
+ }
+ 
+ static void __exit poly1305_simd_mod_exit(void)
+ {
+-	crypto_unregister_shash(&alg);
++	if (IS_REACHABLE(CONFIG_CRYPTO_HASH))
++		crypto_unregister_shash(&alg);
+ }
+ 
+ module_init(poly1305_simd_mod_init);