mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-26 15:05:24 +07:00
b36d8c09e7
Instead of falling back to the generic ChaCha skcipher driver for non-SIMD cases, use a fast scalar implementation for ARM authored by Eric Biggers. This removes the module dependency on chacha-generic altogether, which also simplifies things when we expose the ChaCha library interface from this module. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
461 lines
11 KiB
ArmAsm
461 lines
11 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Copyright (C) 2018 Google, Inc.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/assembler.h>
|
|
|
|
/*
|
|
* Design notes:
|
|
*
|
|
* 16 registers would be needed to hold the state matrix, but only 14 are
|
|
* available because 'sp' and 'pc' cannot be used. So we spill the elements
|
|
* (x8, x9) to the stack and swap them out with (x10, x11). This adds one
|
|
* 'ldrd' and one 'strd' instruction per round.
|
|
*
|
|
* All rotates are performed using the implicit rotate operand accepted by the
|
|
* 'add' and 'eor' instructions. This is faster than using explicit rotate
|
|
* instructions. To make this work, we allow the values in the second and last
|
|
* rows of the ChaCha state matrix (rows 'b' and 'd') to temporarily have the
|
|
* wrong rotation amount. The rotation amount is then fixed up just in time
|
|
* when the values are used. 'brot' is the number of bits the values in row 'b'
|
|
* need to be rotated right to arrive at the correct values, and 'drot'
|
|
* similarly for row 'd'. (brot, drot) start out as (0, 0) but we make it such
|
|
* that they end up as (25, 24) after every round.
|
|
*/
|
|
|
|
// ChaCha state registers
|
|
X0 .req r0
|
|
X1 .req r1
|
|
X2 .req r2
|
|
X3 .req r3
|
|
X4 .req r4
|
|
X5 .req r5
|
|
X6 .req r6
|
|
X7 .req r7
|
|
X8_X10 .req r8 // shared by x8 and x10
|
|
X9_X11 .req r9 // shared by x9 and x11
|
|
X12 .req r10
|
|
X13 .req r11
|
|
X14 .req r12
|
|
X15 .req r14
|
|
|
|
.macro __rev out, in, t0, t1, t2
|
|
.if __LINUX_ARM_ARCH__ >= 6
|
|
rev \out, \in
|
|
.else
|
|
lsl \t0, \in, #24
|
|
and \t1, \in, #0xff00
|
|
and \t2, \in, #0xff0000
|
|
orr \out, \t0, \in, lsr #24
|
|
orr \out, \out, \t1, lsl #8
|
|
orr \out, \out, \t2, lsr #8
|
|
.endif
|
|
.endm
|
|
|
|
.macro _le32_bswap x, t0, t1, t2
|
|
#ifdef __ARMEB__
|
|
__rev \x, \x, \t0, \t1, \t2
|
|
#endif
|
|
.endm
|
|
|
|
.macro _le32_bswap_4x a, b, c, d, t0, t1, t2
|
|
_le32_bswap \a, \t0, \t1, \t2
|
|
_le32_bswap \b, \t0, \t1, \t2
|
|
_le32_bswap \c, \t0, \t1, \t2
|
|
_le32_bswap \d, \t0, \t1, \t2
|
|
.endm
|
|
|
|
.macro __ldrd a, b, src, offset
|
|
#if __LINUX_ARM_ARCH__ >= 6
|
|
ldrd \a, \b, [\src, #\offset]
|
|
#else
|
|
ldr \a, [\src, #\offset]
|
|
ldr \b, [\src, #\offset + 4]
|
|
#endif
|
|
.endm
|
|
|
|
.macro __strd a, b, dst, offset
|
|
#if __LINUX_ARM_ARCH__ >= 6
|
|
strd \a, \b, [\dst, #\offset]
|
|
#else
|
|
str \a, [\dst, #\offset]
|
|
str \b, [\dst, #\offset + 4]
|
|
#endif
|
|
.endm
|
|
|
|
.macro _halfround a1, b1, c1, d1, a2, b2, c2, d2
|
|
|
|
// a += b; d ^= a; d = rol(d, 16);
|
|
add \a1, \a1, \b1, ror #brot
|
|
add \a2, \a2, \b2, ror #brot
|
|
eor \d1, \a1, \d1, ror #drot
|
|
eor \d2, \a2, \d2, ror #drot
|
|
// drot == 32 - 16 == 16
|
|
|
|
// c += d; b ^= c; b = rol(b, 12);
|
|
add \c1, \c1, \d1, ror #16
|
|
add \c2, \c2, \d2, ror #16
|
|
eor \b1, \c1, \b1, ror #brot
|
|
eor \b2, \c2, \b2, ror #brot
|
|
// brot == 32 - 12 == 20
|
|
|
|
// a += b; d ^= a; d = rol(d, 8);
|
|
add \a1, \a1, \b1, ror #20
|
|
add \a2, \a2, \b2, ror #20
|
|
eor \d1, \a1, \d1, ror #16
|
|
eor \d2, \a2, \d2, ror #16
|
|
// drot == 32 - 8 == 24
|
|
|
|
// c += d; b ^= c; b = rol(b, 7);
|
|
add \c1, \c1, \d1, ror #24
|
|
add \c2, \c2, \d2, ror #24
|
|
eor \b1, \c1, \b1, ror #20
|
|
eor \b2, \c2, \b2, ror #20
|
|
// brot == 32 - 7 == 25
|
|
.endm
|
|
|
|
.macro _doubleround
|
|
|
|
// column round
|
|
|
|
// quarterrounds: (x0, x4, x8, x12) and (x1, x5, x9, x13)
|
|
_halfround X0, X4, X8_X10, X12, X1, X5, X9_X11, X13
|
|
|
|
// save (x8, x9); restore (x10, x11)
|
|
__strd X8_X10, X9_X11, sp, 0
|
|
__ldrd X8_X10, X9_X11, sp, 8
|
|
|
|
// quarterrounds: (x2, x6, x10, x14) and (x3, x7, x11, x15)
|
|
_halfround X2, X6, X8_X10, X14, X3, X7, X9_X11, X15
|
|
|
|
.set brot, 25
|
|
.set drot, 24
|
|
|
|
// diagonal round
|
|
|
|
// quarterrounds: (x0, x5, x10, x15) and (x1, x6, x11, x12)
|
|
_halfround X0, X5, X8_X10, X15, X1, X6, X9_X11, X12
|
|
|
|
// save (x10, x11); restore (x8, x9)
|
|
__strd X8_X10, X9_X11, sp, 8
|
|
__ldrd X8_X10, X9_X11, sp, 0
|
|
|
|
// quarterrounds: (x2, x7, x8, x13) and (x3, x4, x9, x14)
|
|
_halfround X2, X7, X8_X10, X13, X3, X4, X9_X11, X14
|
|
.endm
|
|
|
|
.macro _chacha_permute nrounds
|
|
.set brot, 0
|
|
.set drot, 0
|
|
.rept \nrounds / 2
|
|
_doubleround
|
|
.endr
|
|
.endm
|
|
|
|
.macro _chacha nrounds
|
|
|
|
.Lnext_block\@:
|
|
// Stack: unused0-unused1 x10-x11 x0-x15 OUT IN LEN
|
|
// Registers contain x0-x9,x12-x15.
|
|
|
|
// Do the core ChaCha permutation to update x0-x15.
|
|
_chacha_permute \nrounds
|
|
|
|
add sp, #8
|
|
// Stack: x10-x11 orig_x0-orig_x15 OUT IN LEN
|
|
// Registers contain x0-x9,x12-x15.
|
|
// x4-x7 are rotated by 'brot'; x12-x15 are rotated by 'drot'.
|
|
|
|
// Free up some registers (r8-r12,r14) by pushing (x8-x9,x12-x15).
|
|
push {X8_X10, X9_X11, X12, X13, X14, X15}
|
|
|
|
// Load (OUT, IN, LEN).
|
|
ldr r14, [sp, #96]
|
|
ldr r12, [sp, #100]
|
|
ldr r11, [sp, #104]
|
|
|
|
orr r10, r14, r12
|
|
|
|
// Use slow path if fewer than 64 bytes remain.
|
|
cmp r11, #64
|
|
blt .Lxor_slowpath\@
|
|
|
|
// Use slow path if IN and/or OUT isn't 4-byte aligned. Needed even on
|
|
// ARMv6+, since ldmia and stmia (used below) still require alignment.
|
|
tst r10, #3
|
|
bne .Lxor_slowpath\@
|
|
|
|
// Fast path: XOR 64 bytes of aligned data.
|
|
|
|
// Stack: x8-x9 x12-x15 x10-x11 orig_x0-orig_x15 OUT IN LEN
|
|
// Registers: r0-r7 are x0-x7; r8-r11 are free; r12 is IN; r14 is OUT.
|
|
// x4-x7 are rotated by 'brot'; x12-x15 are rotated by 'drot'.
|
|
|
|
// x0-x3
|
|
__ldrd r8, r9, sp, 32
|
|
__ldrd r10, r11, sp, 40
|
|
add X0, X0, r8
|
|
add X1, X1, r9
|
|
add X2, X2, r10
|
|
add X3, X3, r11
|
|
_le32_bswap_4x X0, X1, X2, X3, r8, r9, r10
|
|
ldmia r12!, {r8-r11}
|
|
eor X0, X0, r8
|
|
eor X1, X1, r9
|
|
eor X2, X2, r10
|
|
eor X3, X3, r11
|
|
stmia r14!, {X0-X3}
|
|
|
|
// x4-x7
|
|
__ldrd r8, r9, sp, 48
|
|
__ldrd r10, r11, sp, 56
|
|
add X4, r8, X4, ror #brot
|
|
add X5, r9, X5, ror #brot
|
|
ldmia r12!, {X0-X3}
|
|
add X6, r10, X6, ror #brot
|
|
add X7, r11, X7, ror #brot
|
|
_le32_bswap_4x X4, X5, X6, X7, r8, r9, r10
|
|
eor X4, X4, X0
|
|
eor X5, X5, X1
|
|
eor X6, X6, X2
|
|
eor X7, X7, X3
|
|
stmia r14!, {X4-X7}
|
|
|
|
// x8-x15
|
|
pop {r0-r7} // (x8-x9,x12-x15,x10-x11)
|
|
__ldrd r8, r9, sp, 32
|
|
__ldrd r10, r11, sp, 40
|
|
add r0, r0, r8 // x8
|
|
add r1, r1, r9 // x9
|
|
add r6, r6, r10 // x10
|
|
add r7, r7, r11 // x11
|
|
_le32_bswap_4x r0, r1, r6, r7, r8, r9, r10
|
|
ldmia r12!, {r8-r11}
|
|
eor r0, r0, r8 // x8
|
|
eor r1, r1, r9 // x9
|
|
eor r6, r6, r10 // x10
|
|
eor r7, r7, r11 // x11
|
|
stmia r14!, {r0,r1,r6,r7}
|
|
ldmia r12!, {r0,r1,r6,r7}
|
|
__ldrd r8, r9, sp, 48
|
|
__ldrd r10, r11, sp, 56
|
|
add r2, r8, r2, ror #drot // x12
|
|
add r3, r9, r3, ror #drot // x13
|
|
add r4, r10, r4, ror #drot // x14
|
|
add r5, r11, r5, ror #drot // x15
|
|
_le32_bswap_4x r2, r3, r4, r5, r9, r10, r11
|
|
ldr r9, [sp, #72] // load LEN
|
|
eor r2, r2, r0 // x12
|
|
eor r3, r3, r1 // x13
|
|
eor r4, r4, r6 // x14
|
|
eor r5, r5, r7 // x15
|
|
subs r9, #64 // decrement and check LEN
|
|
stmia r14!, {r2-r5}
|
|
|
|
beq .Ldone\@
|
|
|
|
.Lprepare_for_next_block\@:
|
|
|
|
// Stack: x0-x15 OUT IN LEN
|
|
|
|
// Increment block counter (x12)
|
|
add r8, #1
|
|
|
|
// Store updated (OUT, IN, LEN)
|
|
str r14, [sp, #64]
|
|
str r12, [sp, #68]
|
|
str r9, [sp, #72]
|
|
|
|
mov r14, sp
|
|
|
|
// Store updated block counter (x12)
|
|
str r8, [sp, #48]
|
|
|
|
sub sp, #16
|
|
|
|
// Reload state and do next block
|
|
ldmia r14!, {r0-r11} // load x0-x11
|
|
__strd r10, r11, sp, 8 // store x10-x11 before state
|
|
ldmia r14, {r10-r12,r14} // load x12-x15
|
|
b .Lnext_block\@
|
|
|
|
.Lxor_slowpath\@:
|
|
// Slow path: < 64 bytes remaining, or unaligned input or output buffer.
|
|
// We handle it by storing the 64 bytes of keystream to the stack, then
|
|
// XOR-ing the needed portion with the data.
|
|
|
|
// Allocate keystream buffer
|
|
sub sp, #64
|
|
mov r14, sp
|
|
|
|
// Stack: ks0-ks15 x8-x9 x12-x15 x10-x11 orig_x0-orig_x15 OUT IN LEN
|
|
// Registers: r0-r7 are x0-x7; r8-r11 are free; r12 is IN; r14 is &ks0.
|
|
// x4-x7 are rotated by 'brot'; x12-x15 are rotated by 'drot'.
|
|
|
|
// Save keystream for x0-x3
|
|
__ldrd r8, r9, sp, 96
|
|
__ldrd r10, r11, sp, 104
|
|
add X0, X0, r8
|
|
add X1, X1, r9
|
|
add X2, X2, r10
|
|
add X3, X3, r11
|
|
_le32_bswap_4x X0, X1, X2, X3, r8, r9, r10
|
|
stmia r14!, {X0-X3}
|
|
|
|
// Save keystream for x4-x7
|
|
__ldrd r8, r9, sp, 112
|
|
__ldrd r10, r11, sp, 120
|
|
add X4, r8, X4, ror #brot
|
|
add X5, r9, X5, ror #brot
|
|
add X6, r10, X6, ror #brot
|
|
add X7, r11, X7, ror #brot
|
|
_le32_bswap_4x X4, X5, X6, X7, r8, r9, r10
|
|
add r8, sp, #64
|
|
stmia r14!, {X4-X7}
|
|
|
|
// Save keystream for x8-x15
|
|
ldm r8, {r0-r7} // (x8-x9,x12-x15,x10-x11)
|
|
__ldrd r8, r9, sp, 128
|
|
__ldrd r10, r11, sp, 136
|
|
add r0, r0, r8 // x8
|
|
add r1, r1, r9 // x9
|
|
add r6, r6, r10 // x10
|
|
add r7, r7, r11 // x11
|
|
_le32_bswap_4x r0, r1, r6, r7, r8, r9, r10
|
|
stmia r14!, {r0,r1,r6,r7}
|
|
__ldrd r8, r9, sp, 144
|
|
__ldrd r10, r11, sp, 152
|
|
add r2, r8, r2, ror #drot // x12
|
|
add r3, r9, r3, ror #drot // x13
|
|
add r4, r10, r4, ror #drot // x14
|
|
add r5, r11, r5, ror #drot // x15
|
|
_le32_bswap_4x r2, r3, r4, r5, r9, r10, r11
|
|
stmia r14, {r2-r5}
|
|
|
|
// Stack: ks0-ks15 unused0-unused7 x0-x15 OUT IN LEN
|
|
// Registers: r8 is block counter, r12 is IN.
|
|
|
|
ldr r9, [sp, #168] // LEN
|
|
ldr r14, [sp, #160] // OUT
|
|
cmp r9, #64
|
|
mov r0, sp
|
|
movle r1, r9
|
|
movgt r1, #64
|
|
// r1 is number of bytes to XOR, in range [1, 64]
|
|
|
|
.if __LINUX_ARM_ARCH__ < 6
|
|
orr r2, r12, r14
|
|
tst r2, #3 // IN or OUT misaligned?
|
|
bne .Lxor_next_byte\@
|
|
.endif
|
|
|
|
// XOR a word at a time
|
|
.rept 16
|
|
subs r1, #4
|
|
blt .Lxor_words_done\@
|
|
ldr r2, [r12], #4
|
|
ldr r3, [r0], #4
|
|
eor r2, r2, r3
|
|
str r2, [r14], #4
|
|
.endr
|
|
b .Lxor_slowpath_done\@
|
|
.Lxor_words_done\@:
|
|
ands r1, r1, #3
|
|
beq .Lxor_slowpath_done\@
|
|
|
|
// XOR a byte at a time
|
|
.Lxor_next_byte\@:
|
|
ldrb r2, [r12], #1
|
|
ldrb r3, [r0], #1
|
|
eor r2, r2, r3
|
|
strb r2, [r14], #1
|
|
subs r1, #1
|
|
bne .Lxor_next_byte\@
|
|
|
|
.Lxor_slowpath_done\@:
|
|
subs r9, #64
|
|
add sp, #96
|
|
bgt .Lprepare_for_next_block\@
|
|
|
|
.Ldone\@:
|
|
.endm // _chacha
|
|
|
|
/*
|
|
* void chacha_doarm(u8 *dst, const u8 *src, unsigned int bytes,
|
|
* const u32 *state, int nrounds);
|
|
*/
|
|
ENTRY(chacha_doarm)
|
|
cmp r2, #0 // len == 0?
|
|
reteq lr
|
|
|
|
ldr ip, [sp]
|
|
cmp ip, #12
|
|
|
|
push {r0-r2,r4-r11,lr}
|
|
|
|
// Push state x0-x15 onto stack.
|
|
// Also store an extra copy of x10-x11 just before the state.
|
|
|
|
add X12, r3, #48
|
|
ldm X12, {X12,X13,X14,X15}
|
|
push {X12,X13,X14,X15}
|
|
sub sp, sp, #64
|
|
|
|
__ldrd X8_X10, X9_X11, r3, 40
|
|
__strd X8_X10, X9_X11, sp, 8
|
|
__strd X8_X10, X9_X11, sp, 56
|
|
ldm r3, {X0-X9_X11}
|
|
__strd X0, X1, sp, 16
|
|
__strd X2, X3, sp, 24
|
|
__strd X4, X5, sp, 32
|
|
__strd X6, X7, sp, 40
|
|
__strd X8_X10, X9_X11, sp, 48
|
|
|
|
beq 1f
|
|
_chacha 20
|
|
|
|
0: add sp, #76
|
|
pop {r4-r11, pc}
|
|
|
|
1: _chacha 12
|
|
b 0b
|
|
ENDPROC(chacha_doarm)
|
|
|
|
/*
|
|
* void hchacha_block_arm(const u32 state[16], u32 out[8], int nrounds);
|
|
*/
|
|
ENTRY(hchacha_block_arm)
|
|
push {r1,r4-r11,lr}
|
|
|
|
cmp r2, #12 // ChaCha12 ?
|
|
|
|
mov r14, r0
|
|
ldmia r14!, {r0-r11} // load x0-x11
|
|
push {r10-r11} // store x10-x11 to stack
|
|
ldm r14, {r10-r12,r14} // load x12-x15
|
|
sub sp, #8
|
|
|
|
beq 1f
|
|
_chacha_permute 20
|
|
|
|
// Skip over (unused0-unused1, x10-x11)
|
|
0: add sp, #16
|
|
|
|
// Fix up rotations of x12-x15
|
|
ror X12, X12, #drot
|
|
ror X13, X13, #drot
|
|
pop {r4} // load 'out'
|
|
ror X14, X14, #drot
|
|
ror X15, X15, #drot
|
|
|
|
// Store (x0-x3,x12-x15) to 'out'
|
|
stm r4, {X0,X1,X2,X3,X12,X13,X14,X15}
|
|
|
|
pop {r4-r11,pc}
|
|
|
|
1: _chacha_permute 12
|
|
b 0b
|
|
ENDPROC(hchacha_block_arm)
|