Commit a5dd97f8 authored by Martin Willi's avatar Martin Willi Committed by Herbert Xu

crypto: x86/chacha20 - Add a 2-block AVX2 variant

This variant uses the same principle as the single block SSSE3 variant
by shuffling the state matrix after each round. With the wider AVX
registers, we can do two blocks in parallel, though.

This function can increase performance and efficiency significantly for
lengths that would otherwise require a 4-block function.
Signed-off-by: default avatarMartin Willi <martin@strongswan.org>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 9b17608f
...@@ -26,8 +26,205 @@ ROT16: .octa 0x0d0c0f0e09080b0a0504070601000302 ...@@ -26,8 +26,205 @@ ROT16: .octa 0x0d0c0f0e09080b0a0504070601000302
CTRINC: .octa 0x00000003000000020000000100000000 CTRINC: .octa 0x00000003000000020000000100000000
.octa 0x00000007000000060000000500000004 .octa 0x00000007000000060000000500000004
.section .rodata.cst32.CTR2BL, "aM", @progbits, 32
.align 32
CTR2BL: .octa 0x00000000000000000000000000000000
.octa 0x00000000000000000000000000000001
.text .text
ENTRY(chacha20_2block_xor_avx2)
# %rdi: Input state matrix, s
# %rsi: up to 2 data blocks output, o
# %rdx: up to 2 data blocks input, i
# %rcx: input/output length in bytes
# This function encrypts two ChaCha20 blocks by loading the state
# matrix twice across four AVX registers. It performs matrix operations
# on four words in each matrix in parallel, but requires shuffling to
# rearrange the words after each round.
vzeroupper
# x0..3[0-2] = s0..3
vbroadcasti128 0x00(%rdi),%ymm0
vbroadcasti128 0x10(%rdi),%ymm1
vbroadcasti128 0x20(%rdi),%ymm2
vbroadcasti128 0x30(%rdi),%ymm3
vpaddd CTR2BL(%rip),%ymm3,%ymm3
vmovdqa %ymm0,%ymm8
vmovdqa %ymm1,%ymm9
vmovdqa %ymm2,%ymm10
vmovdqa %ymm3,%ymm11
vmovdqa ROT8(%rip),%ymm4
vmovdqa ROT16(%rip),%ymm5
mov %rcx,%rax
mov $10,%ecx
.Ldoubleround:
# x0 += x1, x3 = rotl32(x3 ^ x0, 16)
vpaddd %ymm1,%ymm0,%ymm0
vpxor %ymm0,%ymm3,%ymm3
vpshufb %ymm5,%ymm3,%ymm3
# x2 += x3, x1 = rotl32(x1 ^ x2, 12)
vpaddd %ymm3,%ymm2,%ymm2
vpxor %ymm2,%ymm1,%ymm1
vmovdqa %ymm1,%ymm6
vpslld $12,%ymm6,%ymm6
vpsrld $20,%ymm1,%ymm1
vpor %ymm6,%ymm1,%ymm1
# x0 += x1, x3 = rotl32(x3 ^ x0, 8)
vpaddd %ymm1,%ymm0,%ymm0
vpxor %ymm0,%ymm3,%ymm3
vpshufb %ymm4,%ymm3,%ymm3
# x2 += x3, x1 = rotl32(x1 ^ x2, 7)
vpaddd %ymm3,%ymm2,%ymm2
vpxor %ymm2,%ymm1,%ymm1
vmovdqa %ymm1,%ymm7
vpslld $7,%ymm7,%ymm7
vpsrld $25,%ymm1,%ymm1
vpor %ymm7,%ymm1,%ymm1
# x1 = shuffle32(x1, MASK(0, 3, 2, 1))
vpshufd $0x39,%ymm1,%ymm1
# x2 = shuffle32(x2, MASK(1, 0, 3, 2))
vpshufd $0x4e,%ymm2,%ymm2
# x3 = shuffle32(x3, MASK(2, 1, 0, 3))
vpshufd $0x93,%ymm3,%ymm3
# x0 += x1, x3 = rotl32(x3 ^ x0, 16)
vpaddd %ymm1,%ymm0,%ymm0
vpxor %ymm0,%ymm3,%ymm3
vpshufb %ymm5,%ymm3,%ymm3
# x2 += x3, x1 = rotl32(x1 ^ x2, 12)
vpaddd %ymm3,%ymm2,%ymm2
vpxor %ymm2,%ymm1,%ymm1
vmovdqa %ymm1,%ymm6
vpslld $12,%ymm6,%ymm6
vpsrld $20,%ymm1,%ymm1
vpor %ymm6,%ymm1,%ymm1
# x0 += x1, x3 = rotl32(x3 ^ x0, 8)
vpaddd %ymm1,%ymm0,%ymm0
vpxor %ymm0,%ymm3,%ymm3
vpshufb %ymm4,%ymm3,%ymm3
# x2 += x3, x1 = rotl32(x1 ^ x2, 7)
vpaddd %ymm3,%ymm2,%ymm2
vpxor %ymm2,%ymm1,%ymm1
vmovdqa %ymm1,%ymm7
vpslld $7,%ymm7,%ymm7
vpsrld $25,%ymm1,%ymm1
vpor %ymm7,%ymm1,%ymm1
# x1 = shuffle32(x1, MASK(2, 1, 0, 3))
vpshufd $0x93,%ymm1,%ymm1
# x2 = shuffle32(x2, MASK(1, 0, 3, 2))
vpshufd $0x4e,%ymm2,%ymm2
# x3 = shuffle32(x3, MASK(0, 3, 2, 1))
vpshufd $0x39,%ymm3,%ymm3
dec %ecx
jnz .Ldoubleround
# o0 = i0 ^ (x0 + s0)
vpaddd %ymm8,%ymm0,%ymm7
cmp $0x10,%rax
jl .Lxorpart2
vpxor 0x00(%rdx),%xmm7,%xmm6
vmovdqu %xmm6,0x00(%rsi)
vextracti128 $1,%ymm7,%xmm0
# o1 = i1 ^ (x1 + s1)
vpaddd %ymm9,%ymm1,%ymm7
cmp $0x20,%rax
jl .Lxorpart2
vpxor 0x10(%rdx),%xmm7,%xmm6
vmovdqu %xmm6,0x10(%rsi)
vextracti128 $1,%ymm7,%xmm1
# o2 = i2 ^ (x2 + s2)
vpaddd %ymm10,%ymm2,%ymm7
cmp $0x30,%rax
jl .Lxorpart2
vpxor 0x20(%rdx),%xmm7,%xmm6
vmovdqu %xmm6,0x20(%rsi)
vextracti128 $1,%ymm7,%xmm2
# o3 = i3 ^ (x3 + s3)
vpaddd %ymm11,%ymm3,%ymm7
cmp $0x40,%rax
jl .Lxorpart2
vpxor 0x30(%rdx),%xmm7,%xmm6
vmovdqu %xmm6,0x30(%rsi)
vextracti128 $1,%ymm7,%xmm3
# xor and write second block
vmovdqa %xmm0,%xmm7
cmp $0x50,%rax
jl .Lxorpart2
vpxor 0x40(%rdx),%xmm7,%xmm6
vmovdqu %xmm6,0x40(%rsi)
vmovdqa %xmm1,%xmm7
cmp $0x60,%rax
jl .Lxorpart2
vpxor 0x50(%rdx),%xmm7,%xmm6
vmovdqu %xmm6,0x50(%rsi)
vmovdqa %xmm2,%xmm7
cmp $0x70,%rax
jl .Lxorpart2
vpxor 0x60(%rdx),%xmm7,%xmm6
vmovdqu %xmm6,0x60(%rsi)
vmovdqa %xmm3,%xmm7
cmp $0x80,%rax
jl .Lxorpart2
vpxor 0x70(%rdx),%xmm7,%xmm6
vmovdqu %xmm6,0x70(%rsi)
.Ldone2:
vzeroupper
ret
.Lxorpart2:
# xor remaining bytes from partial register into output
mov %rax,%r9
and $0x0f,%r9
jz .Ldone2
and $~0x0f,%rax
mov %rsi,%r11
lea 8(%rsp),%r10
sub $0x10,%rsp
and $~31,%rsp
lea (%rdx,%rax),%rsi
mov %rsp,%rdi
mov %r9,%rcx
rep movsb
vpxor 0x00(%rsp),%xmm7,%xmm7
vmovdqa %xmm7,0x00(%rsp)
mov %rsp,%rsi
lea (%r11,%rax),%rdi
mov %r9,%rcx
rep movsb
lea -8(%r10),%rsp
jmp .Ldone2
ENDPROC(chacha20_2block_xor_avx2)
ENTRY(chacha20_8block_xor_avx2) ENTRY(chacha20_8block_xor_avx2)
# %rdi: Input state matrix, s # %rdi: Input state matrix, s
# %rsi: up to 8 data blocks output, o # %rsi: up to 8 data blocks output, o
......
...@@ -24,6 +24,8 @@ asmlinkage void chacha20_block_xor_ssse3(u32 *state, u8 *dst, const u8 *src, ...@@ -24,6 +24,8 @@ asmlinkage void chacha20_block_xor_ssse3(u32 *state, u8 *dst, const u8 *src,
asmlinkage void chacha20_4block_xor_ssse3(u32 *state, u8 *dst, const u8 *src, asmlinkage void chacha20_4block_xor_ssse3(u32 *state, u8 *dst, const u8 *src,
unsigned int len); unsigned int len);
#ifdef CONFIG_AS_AVX2 #ifdef CONFIG_AS_AVX2
asmlinkage void chacha20_2block_xor_avx2(u32 *state, u8 *dst, const u8 *src,
unsigned int len);
asmlinkage void chacha20_8block_xor_avx2(u32 *state, u8 *dst, const u8 *src, asmlinkage void chacha20_8block_xor_avx2(u32 *state, u8 *dst, const u8 *src,
unsigned int len); unsigned int len);
static bool chacha20_use_avx2; static bool chacha20_use_avx2;
...@@ -52,6 +54,11 @@ static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src, ...@@ -52,6 +54,11 @@ static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src,
state[12] += chacha20_advance(bytes, 8); state[12] += chacha20_advance(bytes, 8);
return; return;
} }
if (bytes > CHACHA20_BLOCK_SIZE) {
chacha20_2block_xor_avx2(state, dst, src, bytes);
state[12] += chacha20_advance(bytes, 2);
return;
}
} }
#endif #endif
while (bytes >= CHACHA20_BLOCK_SIZE * 4) { while (bytes >= CHACHA20_BLOCK_SIZE * 4) {
......
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