kernel-ark/arch/arm64/crypto/aes-modes.S
Ard Biesheuvel 49788fe2a1 arm64/crypto: AES-ECB/CBC/CTR/XTS using ARMv8 NEON and Crypto Extensions
This adds ARMv8 implementations of AES in ECB, CBC, CTR and XTS modes,
both for ARMv8 with Crypto Extensions and for plain ARMv8 NEON.

The Crypto Extensions version can only run on ARMv8 implementations that
have support for these optional extensions.

The plain NEON version is a table based yet time invariant implementation.
All S-box substitutions are performed in parallel, leveraging the wide range
of ARMv8's tbl/tbx instructions, and the huge NEON register file, which can
comfortably hold the entire S-box and still have room to spare for doing the
actual computations.

The key expansion routines were borrowed from aes_generic.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-05-14 10:04:16 -07:00

533 lines
12 KiB
ArmAsm

/*
* linux/arch/arm64/crypto/aes-modes.S - chaining mode wrappers for AES
*
* Copyright (C) 2013 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.
*/
/* included by aes-ce.S and aes-neon.S */
.text
.align 4
/*
* There are several ways to instantiate this code:
* - no interleave, all inline
* - 2-way interleave, 2x calls out of line (-DINTERLEAVE=2)
* - 2-way interleave, all inline (-DINTERLEAVE=2 -DINTERLEAVE_INLINE)
* - 4-way interleave, 4x calls out of line (-DINTERLEAVE=4)
* - 4-way interleave, all inline (-DINTERLEAVE=4 -DINTERLEAVE_INLINE)
*
* Macros imported by this code:
* - enc_prepare - setup NEON registers for encryption
* - dec_prepare - setup NEON registers for decryption
* - enc_switch_key - change to new key after having prepared for encryption
* - encrypt_block - encrypt a single block
* - decrypt block - decrypt a single block
* - encrypt_block2x - encrypt 2 blocks in parallel (if INTERLEAVE == 2)
* - decrypt_block2x - decrypt 2 blocks in parallel (if INTERLEAVE == 2)
* - encrypt_block4x - encrypt 4 blocks in parallel (if INTERLEAVE == 4)
* - decrypt_block4x - decrypt 4 blocks in parallel (if INTERLEAVE == 4)
*/
#if defined(INTERLEAVE) && !defined(INTERLEAVE_INLINE)
#define FRAME_PUSH stp x29, x30, [sp,#-16]! ; mov x29, sp
#define FRAME_POP ldp x29, x30, [sp],#16
#if INTERLEAVE == 2
aes_encrypt_block2x:
encrypt_block2x v0, v1, w3, x2, x6, w7
ret
ENDPROC(aes_encrypt_block2x)
aes_decrypt_block2x:
decrypt_block2x v0, v1, w3, x2, x6, w7
ret
ENDPROC(aes_decrypt_block2x)
#elif INTERLEAVE == 4
aes_encrypt_block4x:
encrypt_block4x v0, v1, v2, v3, w3, x2, x6, w7
ret
ENDPROC(aes_encrypt_block4x)
aes_decrypt_block4x:
decrypt_block4x v0, v1, v2, v3, w3, x2, x6, w7
ret
ENDPROC(aes_decrypt_block4x)
#else
#error INTERLEAVE should equal 2 or 4
#endif
.macro do_encrypt_block2x
bl aes_encrypt_block2x
.endm
.macro do_decrypt_block2x
bl aes_decrypt_block2x
.endm
.macro do_encrypt_block4x
bl aes_encrypt_block4x
.endm
.macro do_decrypt_block4x
bl aes_decrypt_block4x
.endm
#else
#define FRAME_PUSH
#define FRAME_POP
.macro do_encrypt_block2x
encrypt_block2x v0, v1, w3, x2, x6, w7
.endm
.macro do_decrypt_block2x
decrypt_block2x v0, v1, w3, x2, x6, w7
.endm
.macro do_encrypt_block4x
encrypt_block4x v0, v1, v2, v3, w3, x2, x6, w7
.endm
.macro do_decrypt_block4x
decrypt_block4x v0, v1, v2, v3, w3, x2, x6, w7
.endm
#endif
/*
* aes_ecb_encrypt(u8 out[], u8 const in[], u8 const rk[], int rounds,
* int blocks, int first)
* aes_ecb_decrypt(u8 out[], u8 const in[], u8 const rk[], int rounds,
* int blocks, int first)
*/
AES_ENTRY(aes_ecb_encrypt)
FRAME_PUSH
cbz w5, .LecbencloopNx
enc_prepare w3, x2, x5
.LecbencloopNx:
#if INTERLEAVE >= 2
subs w4, w4, #INTERLEAVE
bmi .Lecbenc1x
#if INTERLEAVE == 2
ld1 {v0.16b-v1.16b}, [x1], #32 /* get 2 pt blocks */
do_encrypt_block2x
st1 {v0.16b-v1.16b}, [x0], #32
#else
ld1 {v0.16b-v3.16b}, [x1], #64 /* get 4 pt blocks */
do_encrypt_block4x
st1 {v0.16b-v3.16b}, [x0], #64
#endif
b .LecbencloopNx
.Lecbenc1x:
adds w4, w4, #INTERLEAVE
beq .Lecbencout
#endif
.Lecbencloop:
ld1 {v0.16b}, [x1], #16 /* get next pt block */
encrypt_block v0, w3, x2, x5, w6
st1 {v0.16b}, [x0], #16
subs w4, w4, #1
bne .Lecbencloop
.Lecbencout:
FRAME_POP
ret
AES_ENDPROC(aes_ecb_encrypt)
AES_ENTRY(aes_ecb_decrypt)
FRAME_PUSH
cbz w5, .LecbdecloopNx
dec_prepare w3, x2, x5
.LecbdecloopNx:
#if INTERLEAVE >= 2
subs w4, w4, #INTERLEAVE
bmi .Lecbdec1x
#if INTERLEAVE == 2
ld1 {v0.16b-v1.16b}, [x1], #32 /* get 2 ct blocks */
do_decrypt_block2x
st1 {v0.16b-v1.16b}, [x0], #32
#else
ld1 {v0.16b-v3.16b}, [x1], #64 /* get 4 ct blocks */
do_decrypt_block4x
st1 {v0.16b-v3.16b}, [x0], #64
#endif
b .LecbdecloopNx
.Lecbdec1x:
adds w4, w4, #INTERLEAVE
beq .Lecbdecout
#endif
.Lecbdecloop:
ld1 {v0.16b}, [x1], #16 /* get next ct block */
decrypt_block v0, w3, x2, x5, w6
st1 {v0.16b}, [x0], #16
subs w4, w4, #1
bne .Lecbdecloop
.Lecbdecout:
FRAME_POP
ret
AES_ENDPROC(aes_ecb_decrypt)
/*
* aes_cbc_encrypt(u8 out[], u8 const in[], u8 const rk[], int rounds,
* int blocks, u8 iv[], int first)
* aes_cbc_decrypt(u8 out[], u8 const in[], u8 const rk[], int rounds,
* int blocks, u8 iv[], int first)
*/
AES_ENTRY(aes_cbc_encrypt)
cbz w6, .Lcbcencloop
ld1 {v0.16b}, [x5] /* get iv */
enc_prepare w3, x2, x5
.Lcbcencloop:
ld1 {v1.16b}, [x1], #16 /* get next pt block */
eor v0.16b, v0.16b, v1.16b /* ..and xor with iv */
encrypt_block v0, w3, x2, x5, w6
st1 {v0.16b}, [x0], #16
subs w4, w4, #1
bne .Lcbcencloop
ret
AES_ENDPROC(aes_cbc_encrypt)
AES_ENTRY(aes_cbc_decrypt)
FRAME_PUSH
cbz w6, .LcbcdecloopNx
ld1 {v7.16b}, [x5] /* get iv */
dec_prepare w3, x2, x5
.LcbcdecloopNx:
#if INTERLEAVE >= 2
subs w4, w4, #INTERLEAVE
bmi .Lcbcdec1x
#if INTERLEAVE == 2
ld1 {v0.16b-v1.16b}, [x1], #32 /* get 2 ct blocks */
mov v2.16b, v0.16b
mov v3.16b, v1.16b
do_decrypt_block2x
eor v0.16b, v0.16b, v7.16b
eor v1.16b, v1.16b, v2.16b
mov v7.16b, v3.16b
st1 {v0.16b-v1.16b}, [x0], #32
#else
ld1 {v0.16b-v3.16b}, [x1], #64 /* get 4 ct blocks */
mov v4.16b, v0.16b
mov v5.16b, v1.16b
mov v6.16b, v2.16b
do_decrypt_block4x
sub x1, x1, #16
eor v0.16b, v0.16b, v7.16b
eor v1.16b, v1.16b, v4.16b
ld1 {v7.16b}, [x1], #16 /* reload 1 ct block */
eor v2.16b, v2.16b, v5.16b
eor v3.16b, v3.16b, v6.16b
st1 {v0.16b-v3.16b}, [x0], #64
#endif
b .LcbcdecloopNx
.Lcbcdec1x:
adds w4, w4, #INTERLEAVE
beq .Lcbcdecout
#endif
.Lcbcdecloop:
ld1 {v1.16b}, [x1], #16 /* get next ct block */
mov v0.16b, v1.16b /* ...and copy to v0 */
decrypt_block v0, w3, x2, x5, w6
eor v0.16b, v0.16b, v7.16b /* xor with iv => pt */
mov v7.16b, v1.16b /* ct is next iv */
st1 {v0.16b}, [x0], #16
subs w4, w4, #1
bne .Lcbcdecloop
.Lcbcdecout:
FRAME_POP
ret
AES_ENDPROC(aes_cbc_decrypt)
/*
* aes_ctr_encrypt(u8 out[], u8 const in[], u8 const rk[], int rounds,
* int blocks, u8 ctr[], int first)
*/
AES_ENTRY(aes_ctr_encrypt)
FRAME_PUSH
cbnz w6, .Lctrfirst /* 1st time around? */
umov x5, v4.d[1] /* keep swabbed ctr in reg */
rev x5, x5
#if INTERLEAVE >= 2
cmn w5, w4 /* 32 bit overflow? */
bcs .Lctrinc
add x5, x5, #1 /* increment BE ctr */
b .LctrincNx
#else
b .Lctrinc
#endif
.Lctrfirst:
enc_prepare w3, x2, x6
ld1 {v4.16b}, [x5]
umov x5, v4.d[1] /* keep swabbed ctr in reg */
rev x5, x5
#if INTERLEAVE >= 2
cmn w5, w4 /* 32 bit overflow? */
bcs .Lctrloop
.LctrloopNx:
subs w4, w4, #INTERLEAVE
bmi .Lctr1x
#if INTERLEAVE == 2
mov v0.8b, v4.8b
mov v1.8b, v4.8b
rev x7, x5
add x5, x5, #1
ins v0.d[1], x7
rev x7, x5
add x5, x5, #1
ins v1.d[1], x7
ld1 {v2.16b-v3.16b}, [x1], #32 /* get 2 input blocks */
do_encrypt_block2x
eor v0.16b, v0.16b, v2.16b
eor v1.16b, v1.16b, v3.16b
st1 {v0.16b-v1.16b}, [x0], #32
#else
ldr q8, =0x30000000200000001 /* addends 1,2,3[,0] */
dup v7.4s, w5
mov v0.16b, v4.16b
add v7.4s, v7.4s, v8.4s
mov v1.16b, v4.16b
rev32 v8.16b, v7.16b
mov v2.16b, v4.16b
mov v3.16b, v4.16b
mov v1.s[3], v8.s[0]
mov v2.s[3], v8.s[1]
mov v3.s[3], v8.s[2]
ld1 {v5.16b-v7.16b}, [x1], #48 /* get 3 input blocks */
do_encrypt_block4x
eor v0.16b, v5.16b, v0.16b
ld1 {v5.16b}, [x1], #16 /* get 1 input block */
eor v1.16b, v6.16b, v1.16b
eor v2.16b, v7.16b, v2.16b
eor v3.16b, v5.16b, v3.16b
st1 {v0.16b-v3.16b}, [x0], #64
add x5, x5, #INTERLEAVE
#endif
cbz w4, .LctroutNx
.LctrincNx:
rev x7, x5
ins v4.d[1], x7
b .LctrloopNx
.LctroutNx:
sub x5, x5, #1
rev x7, x5
ins v4.d[1], x7
b .Lctrout
.Lctr1x:
adds w4, w4, #INTERLEAVE
beq .Lctrout
#endif
.Lctrloop:
mov v0.16b, v4.16b
encrypt_block v0, w3, x2, x6, w7
subs w4, w4, #1
bmi .Lctrhalfblock /* blocks < 0 means 1/2 block */
ld1 {v3.16b}, [x1], #16
eor v3.16b, v0.16b, v3.16b
st1 {v3.16b}, [x0], #16
beq .Lctrout
.Lctrinc:
adds x5, x5, #1 /* increment BE ctr */
rev x7, x5
ins v4.d[1], x7
bcc .Lctrloop /* no overflow? */
umov x7, v4.d[0] /* load upper word of ctr */
rev x7, x7 /* ... to handle the carry */
add x7, x7, #1
rev x7, x7
ins v4.d[0], x7
b .Lctrloop
.Lctrhalfblock:
ld1 {v3.8b}, [x1]
eor v3.8b, v0.8b, v3.8b
st1 {v3.8b}, [x0]
.Lctrout:
FRAME_POP
ret
AES_ENDPROC(aes_ctr_encrypt)
.ltorg
/*
* aes_xts_decrypt(u8 out[], u8 const in[], u8 const rk1[], int rounds,
* int blocks, u8 const rk2[], u8 iv[], int first)
* aes_xts_decrypt(u8 out[], u8 const in[], u8 const rk1[], int rounds,
* int blocks, u8 const rk2[], u8 iv[], int first)
*/
.macro next_tweak, out, in, const, tmp
sshr \tmp\().2d, \in\().2d, #63
and \tmp\().16b, \tmp\().16b, \const\().16b
add \out\().2d, \in\().2d, \in\().2d
ext \tmp\().16b, \tmp\().16b, \tmp\().16b, #8
eor \out\().16b, \out\().16b, \tmp\().16b
.endm
.Lxts_mul_x:
.word 1, 0, 0x87, 0
AES_ENTRY(aes_xts_encrypt)
FRAME_PUSH
cbz w7, .LxtsencloopNx
ld1 {v4.16b}, [x6]
enc_prepare w3, x5, x6
encrypt_block v4, w3, x5, x6, w7 /* first tweak */
enc_switch_key w3, x2, x6
ldr q7, .Lxts_mul_x
b .LxtsencNx
.LxtsencloopNx:
ldr q7, .Lxts_mul_x
next_tweak v4, v4, v7, v8
.LxtsencNx:
#if INTERLEAVE >= 2
subs w4, w4, #INTERLEAVE
bmi .Lxtsenc1x
#if INTERLEAVE == 2
ld1 {v0.16b-v1.16b}, [x1], #32 /* get 2 pt blocks */
next_tweak v5, v4, v7, v8
eor v0.16b, v0.16b, v4.16b
eor v1.16b, v1.16b, v5.16b
do_encrypt_block2x
eor v0.16b, v0.16b, v4.16b
eor v1.16b, v1.16b, v5.16b
st1 {v0.16b-v1.16b}, [x0], #32
cbz w4, .LxtsencoutNx
next_tweak v4, v5, v7, v8
b .LxtsencNx
.LxtsencoutNx:
mov v4.16b, v5.16b
b .Lxtsencout
#else
ld1 {v0.16b-v3.16b}, [x1], #64 /* get 4 pt blocks */
next_tweak v5, v4, v7, v8
eor v0.16b, v0.16b, v4.16b
next_tweak v6, v5, v7, v8
eor v1.16b, v1.16b, v5.16b
eor v2.16b, v2.16b, v6.16b
next_tweak v7, v6, v7, v8
eor v3.16b, v3.16b, v7.16b
do_encrypt_block4x
eor v3.16b, v3.16b, v7.16b
eor v0.16b, v0.16b, v4.16b
eor v1.16b, v1.16b, v5.16b
eor v2.16b, v2.16b, v6.16b
st1 {v0.16b-v3.16b}, [x0], #64
mov v4.16b, v7.16b
cbz w4, .Lxtsencout
b .LxtsencloopNx
#endif
.Lxtsenc1x:
adds w4, w4, #INTERLEAVE
beq .Lxtsencout
#endif
.Lxtsencloop:
ld1 {v1.16b}, [x1], #16
eor v0.16b, v1.16b, v4.16b
encrypt_block v0, w3, x2, x6, w7
eor v0.16b, v0.16b, v4.16b
st1 {v0.16b}, [x0], #16
subs w4, w4, #1
beq .Lxtsencout
next_tweak v4, v4, v7, v8
b .Lxtsencloop
.Lxtsencout:
FRAME_POP
ret
AES_ENDPROC(aes_xts_encrypt)
AES_ENTRY(aes_xts_decrypt)
FRAME_PUSH
cbz w7, .LxtsdecloopNx
ld1 {v4.16b}, [x6]
enc_prepare w3, x5, x6
encrypt_block v4, w3, x5, x6, w7 /* first tweak */
dec_prepare w3, x2, x6
ldr q7, .Lxts_mul_x
b .LxtsdecNx
.LxtsdecloopNx:
ldr q7, .Lxts_mul_x
next_tweak v4, v4, v7, v8
.LxtsdecNx:
#if INTERLEAVE >= 2
subs w4, w4, #INTERLEAVE
bmi .Lxtsdec1x
#if INTERLEAVE == 2
ld1 {v0.16b-v1.16b}, [x1], #32 /* get 2 ct blocks */
next_tweak v5, v4, v7, v8
eor v0.16b, v0.16b, v4.16b
eor v1.16b, v1.16b, v5.16b
do_decrypt_block2x
eor v0.16b, v0.16b, v4.16b
eor v1.16b, v1.16b, v5.16b
st1 {v0.16b-v1.16b}, [x0], #32
cbz w4, .LxtsdecoutNx
next_tweak v4, v5, v7, v8
b .LxtsdecNx
.LxtsdecoutNx:
mov v4.16b, v5.16b
b .Lxtsdecout
#else
ld1 {v0.16b-v3.16b}, [x1], #64 /* get 4 ct blocks */
next_tweak v5, v4, v7, v8
eor v0.16b, v0.16b, v4.16b
next_tweak v6, v5, v7, v8
eor v1.16b, v1.16b, v5.16b
eor v2.16b, v2.16b, v6.16b
next_tweak v7, v6, v7, v8
eor v3.16b, v3.16b, v7.16b
do_decrypt_block4x
eor v3.16b, v3.16b, v7.16b
eor v0.16b, v0.16b, v4.16b
eor v1.16b, v1.16b, v5.16b
eor v2.16b, v2.16b, v6.16b
st1 {v0.16b-v3.16b}, [x0], #64
mov v4.16b, v7.16b
cbz w4, .Lxtsdecout
b .LxtsdecloopNx
#endif
.Lxtsdec1x:
adds w4, w4, #INTERLEAVE
beq .Lxtsdecout
#endif
.Lxtsdecloop:
ld1 {v1.16b}, [x1], #16
eor v0.16b, v1.16b, v4.16b
decrypt_block v0, w3, x2, x6, w7
eor v0.16b, v0.16b, v4.16b
st1 {v0.16b}, [x0], #16
subs w4, w4, #1
beq .Lxtsdecout
next_tweak v4, v4, v7, v8
b .Lxtsdecloop
.Lxtsdecout:
FRAME_POP
ret
AES_ENDPROC(aes_xts_decrypt)