These make a big difference when doing WireGuard with small armv7 routers, and the 5.4 backport already has it. Suggested-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com> Cc: David Bauer <mail@david-bauer.net> Cc: Petr Štetiar <ynezz@true.cz> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
		
			
				
	
	
		
			39 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			39 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
From 7f63462faf9eab69132bea9abd48c2c05a93145b Mon Sep 17 00:00:00 2001
 | 
						|
From: Ard Biesheuvel <ardb@kernel.org>
 | 
						|
Date: Sun, 13 Dec 2020 15:39:29 +0100
 | 
						|
Subject: [PATCH 2/2] crypto: arm/chacha-neon - add missing counter increment
 | 
						|
 | 
						|
commit fd16931a2f518a32753920ff20895e5cf04c8ff1 upstream.
 | 
						|
 | 
						|
Commit 86cd97ec4b943af3 ("crypto: arm/chacha-neon - optimize for non-block
 | 
						|
size multiples") refactored the chacha block handling in the glue code in
 | 
						|
a way that may result in the counter increment to be omitted when calling
 | 
						|
chacha_block_xor_neon() to process a full block. This violates the skcipher
 | 
						|
API, which requires that the output IV is suitable for handling more input
 | 
						|
as long as the preceding input has been presented in round multiples of the
 | 
						|
block size. Also, the same code is exposed via the chacha library interface
 | 
						|
whose callers may actually rely on this increment to occur even for final
 | 
						|
blocks that are smaller than the chacha block size.
 | 
						|
 | 
						|
So increment the counter after calling chacha_block_xor_neon().
 | 
						|
 | 
						|
Fixes: 86cd97ec4b943af3 ("crypto: arm/chacha-neon - optimize for non-block size multiples")
 | 
						|
Reported-by: Eric Biggers <ebiggers@kernel.org>
 | 
						|
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>
 | 
						|
---
 | 
						|
 arch/arm/crypto/chacha-glue.c | 1 +
 | 
						|
 1 file changed, 1 insertion(+)
 | 
						|
 | 
						|
--- a/arch/arm/crypto/chacha-glue.c
 | 
						|
+++ b/arch/arm/crypto/chacha-glue.c
 | 
						|
@@ -60,6 +60,7 @@ static void chacha_doneon(u32 *state, u8
 | 
						|
 		chacha_block_xor_neon(state, d, s, nrounds);
 | 
						|
 		if (d != dst)
 | 
						|
 			memcpy(dst, buf, bytes);
 | 
						|
+		state[12]++;
 | 
						|
 	}
 | 
						|
 }
 | 
						|
 
 |