linux-stable/arch/mips/crypto/chacha-core.S
Ard Biesheuvel 3a2f58f3ba crypto: mips/chacha - wire up accelerated 32r2 code from Zinc
This integrates the accelerated MIPS 32r2 implementation of ChaCha
into both the API and library interfaces of the kernel crypto stack.

The significance of this is that, in addition to becoming available
as an accelerated library implementation, it can also be used by
existing crypto API code such as Adiantum (for block encryption on
ultra low performance cores) or IPsec using chacha20poly1305. These
are use cases that have already opted into using the abstract crypto
API. In order to support Adiantum, the core assembler routine has
been adapted to take the round count as a function argument rather
than hardcoding it to 20.

Co-developed-by: René van Dorst <opensource@vdorst.com>
Signed-off-by: René van Dorst <opensource@vdorst.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:40 +08:00

497 lines
9.9 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 OR MIT */
/*
* Copyright (C) 2016-2018 René van Dorst <opensource@vdorst.com>. All Rights Reserved.
* Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
*/
#define MASK_U32 0x3c
#define CHACHA20_BLOCK_SIZE 64
#define STACK_SIZE 32
#define X0 $t0
#define X1 $t1
#define X2 $t2
#define X3 $t3
#define X4 $t4
#define X5 $t5
#define X6 $t6
#define X7 $t7
#define X8 $t8
#define X9 $t9
#define X10 $v1
#define X11 $s6
#define X12 $s5
#define X13 $s4
#define X14 $s3
#define X15 $s2
/* Use regs which are overwritten on exit for Tx so we don't leak clear data. */
#define T0 $s1
#define T1 $s0
#define T(n) T ## n
#define X(n) X ## n
/* Input arguments */
#define STATE $a0
#define OUT $a1
#define IN $a2
#define BYTES $a3
/* Output argument */
/* NONCE[0] is kept in a register and not in memory.
* We don't want to touch original value in memory.
* Must be incremented every loop iteration.
*/
#define NONCE_0 $v0
/* SAVED_X and SAVED_CA are set in the jump table.
* Use regs which are overwritten on exit else we don't leak clear data.
* They are used to handling the last bytes which are not multiple of 4.
*/
#define SAVED_X X15
#define SAVED_CA $s7
#define IS_UNALIGNED $s7
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
#define MSB 0
#define LSB 3
#define ROTx rotl
#define ROTR(n) rotr n, 24
#define CPU_TO_LE32(n) \
wsbh n; \
rotr n, 16;
#else
#define MSB 3
#define LSB 0
#define ROTx rotr
#define CPU_TO_LE32(n)
#define ROTR(n)
#endif
#define FOR_EACH_WORD(x) \
x( 0); \
x( 1); \
x( 2); \
x( 3); \
x( 4); \
x( 5); \
x( 6); \
x( 7); \
x( 8); \
x( 9); \
x(10); \
x(11); \
x(12); \
x(13); \
x(14); \
x(15);
#define FOR_EACH_WORD_REV(x) \
x(15); \
x(14); \
x(13); \
x(12); \
x(11); \
x(10); \
x( 9); \
x( 8); \
x( 7); \
x( 6); \
x( 5); \
x( 4); \
x( 3); \
x( 2); \
x( 1); \
x( 0);
#define PLUS_ONE_0 1
#define PLUS_ONE_1 2
#define PLUS_ONE_2 3
#define PLUS_ONE_3 4
#define PLUS_ONE_4 5
#define PLUS_ONE_5 6
#define PLUS_ONE_6 7
#define PLUS_ONE_7 8
#define PLUS_ONE_8 9
#define PLUS_ONE_9 10
#define PLUS_ONE_10 11
#define PLUS_ONE_11 12
#define PLUS_ONE_12 13
#define PLUS_ONE_13 14
#define PLUS_ONE_14 15
#define PLUS_ONE_15 16
#define PLUS_ONE(x) PLUS_ONE_ ## x
#define _CONCAT3(a,b,c) a ## b ## c
#define CONCAT3(a,b,c) _CONCAT3(a,b,c)
#define STORE_UNALIGNED(x) \
CONCAT3(.Lchacha_mips_xor_unaligned_, PLUS_ONE(x), _b: ;) \
.if (x != 12); \
lw T0, (x*4)(STATE); \
.endif; \
lwl T1, (x*4)+MSB ## (IN); \
lwr T1, (x*4)+LSB ## (IN); \
.if (x == 12); \
addu X ## x, NONCE_0; \
.else; \
addu X ## x, T0; \
.endif; \
CPU_TO_LE32(X ## x); \
xor X ## x, T1; \
swl X ## x, (x*4)+MSB ## (OUT); \
swr X ## x, (x*4)+LSB ## (OUT);
#define STORE_ALIGNED(x) \
CONCAT3(.Lchacha_mips_xor_aligned_, PLUS_ONE(x), _b: ;) \
.if (x != 12); \
lw T0, (x*4)(STATE); \
.endif; \
lw T1, (x*4) ## (IN); \
.if (x == 12); \
addu X ## x, NONCE_0; \
.else; \
addu X ## x, T0; \
.endif; \
CPU_TO_LE32(X ## x); \
xor X ## x, T1; \
sw X ## x, (x*4) ## (OUT);
/* Jump table macro.
* Used for setup and handling the last bytes, which are not multiple of 4.
* X15 is free to store Xn
* Every jumptable entry must be equal in size.
*/
#define JMPTBL_ALIGNED(x) \
.Lchacha_mips_jmptbl_aligned_ ## x: ; \
.set noreorder; \
b .Lchacha_mips_xor_aligned_ ## x ## _b; \
.if (x == 12); \
addu SAVED_X, X ## x, NONCE_0; \
.else; \
addu SAVED_X, X ## x, SAVED_CA; \
.endif; \
.set reorder
#define JMPTBL_UNALIGNED(x) \
.Lchacha_mips_jmptbl_unaligned_ ## x: ; \
.set noreorder; \
b .Lchacha_mips_xor_unaligned_ ## x ## _b; \
.if (x == 12); \
addu SAVED_X, X ## x, NONCE_0; \
.else; \
addu SAVED_X, X ## x, SAVED_CA; \
.endif; \
.set reorder
#define AXR(A, B, C, D, K, L, M, N, V, W, Y, Z, S) \
addu X(A), X(K); \
addu X(B), X(L); \
addu X(C), X(M); \
addu X(D), X(N); \
xor X(V), X(A); \
xor X(W), X(B); \
xor X(Y), X(C); \
xor X(Z), X(D); \
rotl X(V), S; \
rotl X(W), S; \
rotl X(Y), S; \
rotl X(Z), S;
.text
.set reorder
.set noat
.globl chacha_crypt_arch
.ent chacha_crypt_arch
chacha_crypt_arch:
.frame $sp, STACK_SIZE, $ra
/* Load number of rounds */
lw $at, 16($sp)
addiu $sp, -STACK_SIZE
/* Return bytes = 0. */
beqz BYTES, .Lchacha_mips_end
lw NONCE_0, 48(STATE)
/* Save s0-s7 */
sw $s0, 0($sp)
sw $s1, 4($sp)
sw $s2, 8($sp)
sw $s3, 12($sp)
sw $s4, 16($sp)
sw $s5, 20($sp)
sw $s6, 24($sp)
sw $s7, 28($sp)
/* Test IN or OUT is unaligned.
* IS_UNALIGNED = ( IN | OUT ) & 0x00000003
*/
or IS_UNALIGNED, IN, OUT
andi IS_UNALIGNED, 0x3
b .Lchacha_rounds_start
.align 4
.Loop_chacha_rounds:
addiu IN, CHACHA20_BLOCK_SIZE
addiu OUT, CHACHA20_BLOCK_SIZE
addiu NONCE_0, 1
.Lchacha_rounds_start:
lw X0, 0(STATE)
lw X1, 4(STATE)
lw X2, 8(STATE)
lw X3, 12(STATE)
lw X4, 16(STATE)
lw X5, 20(STATE)
lw X6, 24(STATE)
lw X7, 28(STATE)
lw X8, 32(STATE)
lw X9, 36(STATE)
lw X10, 40(STATE)
lw X11, 44(STATE)
move X12, NONCE_0
lw X13, 52(STATE)
lw X14, 56(STATE)
lw X15, 60(STATE)
.Loop_chacha_xor_rounds:
addiu $at, -2
AXR( 0, 1, 2, 3, 4, 5, 6, 7, 12,13,14,15, 16);
AXR( 8, 9,10,11, 12,13,14,15, 4, 5, 6, 7, 12);
AXR( 0, 1, 2, 3, 4, 5, 6, 7, 12,13,14,15, 8);
AXR( 8, 9,10,11, 12,13,14,15, 4, 5, 6, 7, 7);
AXR( 0, 1, 2, 3, 5, 6, 7, 4, 15,12,13,14, 16);
AXR(10,11, 8, 9, 15,12,13,14, 5, 6, 7, 4, 12);
AXR( 0, 1, 2, 3, 5, 6, 7, 4, 15,12,13,14, 8);
AXR(10,11, 8, 9, 15,12,13,14, 5, 6, 7, 4, 7);
bnez $at, .Loop_chacha_xor_rounds
addiu BYTES, -(CHACHA20_BLOCK_SIZE)
/* Is data src/dst unaligned? Jump */
bnez IS_UNALIGNED, .Loop_chacha_unaligned
/* Set number rounds here to fill delayslot. */
lw $at, (STACK_SIZE+16)($sp)
/* BYTES < 0, it has no full block. */
bltz BYTES, .Lchacha_mips_no_full_block_aligned
FOR_EACH_WORD_REV(STORE_ALIGNED)
/* BYTES > 0? Loop again. */
bgtz BYTES, .Loop_chacha_rounds
/* Place this here to fill delay slot */
addiu NONCE_0, 1
/* BYTES < 0? Handle last bytes */
bltz BYTES, .Lchacha_mips_xor_bytes
.Lchacha_mips_xor_done:
/* Restore used registers */
lw $s0, 0($sp)
lw $s1, 4($sp)
lw $s2, 8($sp)
lw $s3, 12($sp)
lw $s4, 16($sp)
lw $s5, 20($sp)
lw $s6, 24($sp)
lw $s7, 28($sp)
/* Write NONCE_0 back to right location in state */
sw NONCE_0, 48(STATE)
.Lchacha_mips_end:
addiu $sp, STACK_SIZE
jr $ra
.Lchacha_mips_no_full_block_aligned:
/* Restore the offset on BYTES */
addiu BYTES, CHACHA20_BLOCK_SIZE
/* Get number of full WORDS */
andi $at, BYTES, MASK_U32
/* Load upper half of jump table addr */
lui T0, %hi(.Lchacha_mips_jmptbl_aligned_0)
/* Calculate lower half jump table offset */
ins T0, $at, 1, 6
/* Add offset to STATE */
addu T1, STATE, $at
/* Add lower half jump table addr */
addiu T0, %lo(.Lchacha_mips_jmptbl_aligned_0)
/* Read value from STATE */
lw SAVED_CA, 0(T1)
/* Store remaining bytecounter as negative value */
subu BYTES, $at, BYTES
jr T0
/* Jump table */
FOR_EACH_WORD(JMPTBL_ALIGNED)
.Loop_chacha_unaligned:
/* Set number rounds here to fill delayslot. */
lw $at, (STACK_SIZE+16)($sp)
/* BYTES > 0, it has no full block. */
bltz BYTES, .Lchacha_mips_no_full_block_unaligned
FOR_EACH_WORD_REV(STORE_UNALIGNED)
/* BYTES > 0? Loop again. */
bgtz BYTES, .Loop_chacha_rounds
/* Write NONCE_0 back to right location in state */
sw NONCE_0, 48(STATE)
.set noreorder
/* Fall through to byte handling */
bgez BYTES, .Lchacha_mips_xor_done
.Lchacha_mips_xor_unaligned_0_b:
.Lchacha_mips_xor_aligned_0_b:
/* Place this here to fill delay slot */
addiu NONCE_0, 1
.set reorder
.Lchacha_mips_xor_bytes:
addu IN, $at
addu OUT, $at
/* First byte */
lbu T1, 0(IN)
addiu $at, BYTES, 1
CPU_TO_LE32(SAVED_X)
ROTR(SAVED_X)
xor T1, SAVED_X
sb T1, 0(OUT)
beqz $at, .Lchacha_mips_xor_done
/* Second byte */
lbu T1, 1(IN)
addiu $at, BYTES, 2
ROTx SAVED_X, 8
xor T1, SAVED_X
sb T1, 1(OUT)
beqz $at, .Lchacha_mips_xor_done
/* Third byte */
lbu T1, 2(IN)
ROTx SAVED_X, 8
xor T1, SAVED_X
sb T1, 2(OUT)
b .Lchacha_mips_xor_done
.Lchacha_mips_no_full_block_unaligned:
/* Restore the offset on BYTES */
addiu BYTES, CHACHA20_BLOCK_SIZE
/* Get number of full WORDS */
andi $at, BYTES, MASK_U32
/* Load upper half of jump table addr */
lui T0, %hi(.Lchacha_mips_jmptbl_unaligned_0)
/* Calculate lower half jump table offset */
ins T0, $at, 1, 6
/* Add offset to STATE */
addu T1, STATE, $at
/* Add lower half jump table addr */
addiu T0, %lo(.Lchacha_mips_jmptbl_unaligned_0)
/* Read value from STATE */
lw SAVED_CA, 0(T1)
/* Store remaining bytecounter as negative value */
subu BYTES, $at, BYTES
jr T0
/* Jump table */
FOR_EACH_WORD(JMPTBL_UNALIGNED)
.end chacha_crypt_arch
.set at
/* Input arguments
* STATE $a0
* OUT $a1
* NROUND $a2
*/
#undef X12
#undef X13
#undef X14
#undef X15
#define X12 $a3
#define X13 $at
#define X14 $v0
#define X15 STATE
.set noat
.globl hchacha_block_arch
.ent hchacha_block_arch
hchacha_block_arch:
.frame $sp, STACK_SIZE, $ra
addiu $sp, -STACK_SIZE
/* Save X11(s6) */
sw X11, 0($sp)
lw X0, 0(STATE)
lw X1, 4(STATE)
lw X2, 8(STATE)
lw X3, 12(STATE)
lw X4, 16(STATE)
lw X5, 20(STATE)
lw X6, 24(STATE)
lw X7, 28(STATE)
lw X8, 32(STATE)
lw X9, 36(STATE)
lw X10, 40(STATE)
lw X11, 44(STATE)
lw X12, 48(STATE)
lw X13, 52(STATE)
lw X14, 56(STATE)
lw X15, 60(STATE)
.Loop_hchacha_xor_rounds:
addiu $a2, -2
AXR( 0, 1, 2, 3, 4, 5, 6, 7, 12,13,14,15, 16);
AXR( 8, 9,10,11, 12,13,14,15, 4, 5, 6, 7, 12);
AXR( 0, 1, 2, 3, 4, 5, 6, 7, 12,13,14,15, 8);
AXR( 8, 9,10,11, 12,13,14,15, 4, 5, 6, 7, 7);
AXR( 0, 1, 2, 3, 5, 6, 7, 4, 15,12,13,14, 16);
AXR(10,11, 8, 9, 15,12,13,14, 5, 6, 7, 4, 12);
AXR( 0, 1, 2, 3, 5, 6, 7, 4, 15,12,13,14, 8);
AXR(10,11, 8, 9, 15,12,13,14, 5, 6, 7, 4, 7);
bnez $a2, .Loop_hchacha_xor_rounds
/* Restore used register */
lw X11, 0($sp)
sw X0, 0(OUT)
sw X1, 4(OUT)
sw X2, 8(OUT)
sw X3, 12(OUT)
sw X12, 16(OUT)
sw X13, 20(OUT)
sw X14, 24(OUT)
sw X15, 28(OUT)
addiu $sp, STACK_SIZE
jr $ra
.end hchacha_block_arch
.set at