linux/arch/arm64/crypto/aes-ce-ccm-core.S
Ard Biesheuvel 7b67ae4d5c crypto: arm64/aes-ccm - yield NEON after every block of input
Avoid excessive scheduling delays under a preemptible kernel by
yielding the NEON after every block of input.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-05-12 00:13:07 +08:00

264 lines
6.5 KiB
ArmAsm

/*
* aesce-ccm-core.S - AES-CCM transform for ARMv8 with Crypto Extensions
*
* Copyright (C) 2013 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
.text
.arch armv8-a+crypto
/*
* void ce_aes_ccm_auth_data(u8 mac[], u8 const in[], u32 abytes,
* u32 *macp, u8 const rk[], u32 rounds);
*/
ENTRY(ce_aes_ccm_auth_data)
frame_push 7
mov x19, x0
mov x20, x1
mov x21, x2
mov x22, x3
mov x23, x4
mov x24, x5
ldr w25, [x22] /* leftover from prev round? */
ld1 {v0.16b}, [x0] /* load mac */
cbz w25, 1f
sub w25, w25, #16
eor v1.16b, v1.16b, v1.16b
0: ldrb w7, [x20], #1 /* get 1 byte of input */
subs w21, w21, #1
add w25, w25, #1
ins v1.b[0], w7
ext v1.16b, v1.16b, v1.16b, #1 /* rotate in the input bytes */
beq 8f /* out of input? */
cbnz w25, 0b
eor v0.16b, v0.16b, v1.16b
1: ld1 {v3.4s}, [x23] /* load first round key */
prfm pldl1strm, [x20]
cmp w24, #12 /* which key size? */
add x6, x23, #16
sub w7, w24, #2 /* modified # of rounds */
bmi 2f
bne 5f
mov v5.16b, v3.16b
b 4f
2: mov v4.16b, v3.16b
ld1 {v5.4s}, [x6], #16 /* load 2nd round key */
3: aese v0.16b, v4.16b
aesmc v0.16b, v0.16b
4: ld1 {v3.4s}, [x6], #16 /* load next round key */
aese v0.16b, v5.16b
aesmc v0.16b, v0.16b
5: ld1 {v4.4s}, [x6], #16 /* load next round key */
subs w7, w7, #3
aese v0.16b, v3.16b
aesmc v0.16b, v0.16b
ld1 {v5.4s}, [x6], #16 /* load next round key */
bpl 3b
aese v0.16b, v4.16b
subs w21, w21, #16 /* last data? */
eor v0.16b, v0.16b, v5.16b /* final round */
bmi 6f
ld1 {v1.16b}, [x20], #16 /* load next input block */
eor v0.16b, v0.16b, v1.16b /* xor with mac */
beq 6f
if_will_cond_yield_neon
st1 {v0.16b}, [x19] /* store mac */
do_cond_yield_neon
ld1 {v0.16b}, [x19] /* reload mac */
endif_yield_neon
b 1b
6: st1 {v0.16b}, [x19] /* store mac */
beq 10f
adds w21, w21, #16
beq 10f
mov w25, w21
7: ldrb w7, [x20], #1
umov w6, v0.b[0]
eor w6, w6, w7
strb w6, [x19], #1
subs w21, w21, #1
beq 10f
ext v0.16b, v0.16b, v0.16b, #1 /* rotate out the mac bytes */
b 7b
8: mov w7, w25
add w25, w25, #16
9: ext v1.16b, v1.16b, v1.16b, #1
adds w7, w7, #1
bne 9b
eor v0.16b, v0.16b, v1.16b
st1 {v0.16b}, [x19]
10: str w25, [x22]
frame_pop
ret
ENDPROC(ce_aes_ccm_auth_data)
/*
* void ce_aes_ccm_final(u8 mac[], u8 const ctr[], u8 const rk[],
* u32 rounds);
*/
ENTRY(ce_aes_ccm_final)
ld1 {v3.4s}, [x2], #16 /* load first round key */
ld1 {v0.16b}, [x0] /* load mac */
cmp w3, #12 /* which key size? */
sub w3, w3, #2 /* modified # of rounds */
ld1 {v1.16b}, [x1] /* load 1st ctriv */
bmi 0f
bne 3f
mov v5.16b, v3.16b
b 2f
0: mov v4.16b, v3.16b
1: ld1 {v5.4s}, [x2], #16 /* load next round key */
aese v0.16b, v4.16b
aesmc v0.16b, v0.16b
aese v1.16b, v4.16b
aesmc v1.16b, v1.16b
2: ld1 {v3.4s}, [x2], #16 /* load next round key */
aese v0.16b, v5.16b
aesmc v0.16b, v0.16b
aese v1.16b, v5.16b
aesmc v1.16b, v1.16b
3: ld1 {v4.4s}, [x2], #16 /* load next round key */
subs w3, w3, #3
aese v0.16b, v3.16b
aesmc v0.16b, v0.16b
aese v1.16b, v3.16b
aesmc v1.16b, v1.16b
bpl 1b
aese v0.16b, v4.16b
aese v1.16b, v4.16b
/* final round key cancels out */
eor v0.16b, v0.16b, v1.16b /* en-/decrypt the mac */
st1 {v0.16b}, [x0] /* store result */
ret
ENDPROC(ce_aes_ccm_final)
.macro aes_ccm_do_crypt,enc
frame_push 8
mov x19, x0
mov x20, x1
mov x21, x2
mov x22, x3
mov x23, x4
mov x24, x5
mov x25, x6
ldr x26, [x25, #8] /* load lower ctr */
ld1 {v0.16b}, [x24] /* load mac */
CPU_LE( rev x26, x26 ) /* keep swabbed ctr in reg */
0: /* outer loop */
ld1 {v1.8b}, [x25] /* load upper ctr */
prfm pldl1strm, [x20]
add x26, x26, #1
rev x9, x26
cmp w23, #12 /* which key size? */
sub w7, w23, #2 /* get modified # of rounds */
ins v1.d[1], x9 /* no carry in lower ctr */
ld1 {v3.4s}, [x22] /* load first round key */
add x10, x22, #16
bmi 1f
bne 4f
mov v5.16b, v3.16b
b 3f
1: mov v4.16b, v3.16b
ld1 {v5.4s}, [x10], #16 /* load 2nd round key */
2: /* inner loop: 3 rounds, 2x interleaved */
aese v0.16b, v4.16b
aesmc v0.16b, v0.16b
aese v1.16b, v4.16b
aesmc v1.16b, v1.16b
3: ld1 {v3.4s}, [x10], #16 /* load next round key */
aese v0.16b, v5.16b
aesmc v0.16b, v0.16b
aese v1.16b, v5.16b
aesmc v1.16b, v1.16b
4: ld1 {v4.4s}, [x10], #16 /* load next round key */
subs w7, w7, #3
aese v0.16b, v3.16b
aesmc v0.16b, v0.16b
aese v1.16b, v3.16b
aesmc v1.16b, v1.16b
ld1 {v5.4s}, [x10], #16 /* load next round key */
bpl 2b
aese v0.16b, v4.16b
aese v1.16b, v4.16b
subs w21, w21, #16
bmi 7f /* partial block? */
ld1 {v2.16b}, [x20], #16 /* load next input block */
.if \enc == 1
eor v2.16b, v2.16b, v5.16b /* final round enc+mac */
eor v1.16b, v1.16b, v2.16b /* xor with crypted ctr */
.else
eor v2.16b, v2.16b, v1.16b /* xor with crypted ctr */
eor v1.16b, v2.16b, v5.16b /* final round enc */
.endif
eor v0.16b, v0.16b, v2.16b /* xor mac with pt ^ rk[last] */
st1 {v1.16b}, [x19], #16 /* write output block */
beq 5f
if_will_cond_yield_neon
st1 {v0.16b}, [x24] /* store mac */
do_cond_yield_neon
ld1 {v0.16b}, [x24] /* reload mac */
endif_yield_neon
b 0b
5:
CPU_LE( rev x26, x26 )
st1 {v0.16b}, [x24] /* store mac */
str x26, [x25, #8] /* store lsb end of ctr (BE) */
6: frame_pop
ret
7: eor v0.16b, v0.16b, v5.16b /* final round mac */
eor v1.16b, v1.16b, v5.16b /* final round enc */
st1 {v0.16b}, [x24] /* store mac */
add w21, w21, #16 /* process partial tail block */
8: ldrb w9, [x20], #1 /* get 1 byte of input */
umov w6, v1.b[0] /* get top crypted ctr byte */
umov w7, v0.b[0] /* get top mac byte */
.if \enc == 1
eor w7, w7, w9
eor w9, w9, w6
.else
eor w9, w9, w6
eor w7, w7, w9
.endif
strb w9, [x19], #1 /* store out byte */
strb w7, [x24], #1 /* store mac byte */
subs w21, w21, #1
beq 6b
ext v0.16b, v0.16b, v0.16b, #1 /* shift out mac byte */
ext v1.16b, v1.16b, v1.16b, #1 /* shift out ctr byte */
b 8b
.endm
/*
* void ce_aes_ccm_encrypt(u8 out[], u8 const in[], u32 cbytes,
* u8 const rk[], u32 rounds, u8 mac[],
* u8 ctr[]);
* void ce_aes_ccm_decrypt(u8 out[], u8 const in[], u32 cbytes,
* u8 const rk[], u32 rounds, u8 mac[],
* u8 ctr[]);
*/
ENTRY(ce_aes_ccm_encrypt)
aes_ccm_do_crypt 1
ENDPROC(ce_aes_ccm_encrypt)
ENTRY(ce_aes_ccm_decrypt)
aes_ccm_do_crypt 0
ENDPROC(ce_aes_ccm_decrypt)