/*
* aesce-ccm-core.S - AES-CCM transform for ARMv8 with Crypto Extensions
*
* Copyright (C) 2013 - 2014 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>
.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)
ldr w8, [x3] /* leftover from prev round? */
ld1 {v0.2d}, [x0] /* load mac */
cbz w8, 1f
sub w8, w8, #16
eor v1.16b, v1.16b, v1.16b
0: ldrb w7, [x1], #1 /* get 1 byte of input */
subs w2, w2, #1
add w8, w8, #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 w8, 0b
eor v0.16b, v0.16b, v1.16b
1: ld1 {v3.2d}, [x4] /* load first round key */
prfm pldl1strm, [x1]
cmp w5, #12 /* which key size? */
add x6, x4, #16
sub w7, w5, #2 /* modified # of rounds */
bmi 2f
bne 5f
mov v5.16b, v3.16b
b 4f
2: mov v4.16b, v3.16b
ld1 {v5.2d}, [x6], #16 /* load 2nd round key */
3: aese v0.16b, v4.16b
aesmc v0.16b, v0.16b
4: ld1 {v3.2d}, [x6], #16 /* load next round key */
aese v0.16b, v5.16b
aesmc v0.16b, v0.16b
5: ld1 {v4.2d}, [x6], #16 /* load next round key */
subs w7, w7, #3
aese v0.16b, v3.16b
aesmc v0.16b, v0.16b
ld1 {v5.2d}, [x6], #16 /* load next round key */
bpl 3b
aese v0.16b, v4.16b
subs w2, w2, #16 /* last data? */
eor v0.16b, v0.16b, v5.16b /* final round */
bmi 6f
ld1 {v1.16b}, [x1], #16 /* load next input block */
eor v0.16b, v0.16b, v1.16b /* xor with mac */
bne 1b
6: st1 {v0.2d}, [x0] /* store mac */
beq 10f
adds w2, w2, #16
beq 10f
mov w8, w2
7: ldrb w7, [x1], #1
umov w6, v0.b[0]
eor w6, w6, w7
strb w6, [x0], #1
subs w2, w2, #1
beq 10f
ext v0.16b, v0.16b, v0.16b, #1 /* rotate out the mac bytes */
b 7b
8: mov w7, w8
add w8, w8, #16
9: ext v1.16b, v1.16b, v1.16b, #1
adds w7, w7, #1
bne 9b
eor v0.16b, v0.16b, v1.16b
st1 {v0.2d}, [x0]
10: str w8, [x3]
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 {v3.2d}, [x2], #16 /* load first round key */
ld1 {v0.2d}, [x0] /* load mac */
cmp w3, #12 /* which key size? */
sub w3, w3, #2 /* modified # of rounds */
ld1 {v1.2d}, [x1] /* load 1st ctriv */
bmi 0f
bne 3f
mov v5.16b, v3.16b
b 2f
0: mov v4.16b, v3.16b
1: ld1 {v5.2d}, [x2], #16 /* load next round key */
aese v0.16b, v4.16b
aese v1.16b, v4.16b
aesmc v0.16b, v0.16b
aesmc v1.16b, v1.16b
2: ld1 {v3.2d}, [x2], #16 /* load next round key */
aese v0.16b, v5.16b
aese v1.16b, v5.16b
aesmc v0.16b, v0.16b
aesmc v1.16b, v1.16b
3: ld1 {v4.2d}, [x2], #16 /* load next round key */
subs w3, w3, #3
aese v0.16b, v3.16b
aese v1.16b, v3.16b
aesmc v0.16b, v0.16b
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 {v0.2d}, [x0] /* store result */
ret
ENDPROC(ce_aes_ccm_final)
.macro aes_ccm_do_crypt,enc
ldr x8, [x6, #8] /* load lower ctr */
ld1 {v0.2d}, [x5] /* load mac */
rev x8, x8 /* keep swabbed ctr in reg */
0: /* outer loop */
ld1 {v1.1d}, [x6] /* load upper ctr */
prfm pldl1strm, [x1]
add x8, x8, #1
rev x9, x8
cmp w4, #12 /* which key size? */
sub w7, w4, #2 /* get modified # of rounds */
ins v1.d[1], x9 /* no carry in lower ctr */
ld1 {v3.2d}, [x3] /* load first round key */
add x10, x3, #16
bmi 1f
bne 4f
mov v5.16b, v3.16b
b 3f
1: mov v4.16b, v3.16b
ld1 {v5.2d}, [x10], #16 /* load 2nd round key */
2: /* inner loop: 3 rounds, 2x interleaved */
aese v0.16b, v4.16b
aese v1.16b, v4.16b
aesmc v0.16b, v0.16b
aesmc v1.16b, v1.16b
3: ld1 {v3.2d}, [x10], #16 /* load next round key */
aese v0.16b, v5.16b
aese v1.16b, v5.16b
aesmc v0.16b, v0.16b
aesmc v1.16b, v1.16b
4: ld1 {v4.2d}, [x10], #16 /* load next round key */
subs w7, w7, #3
aese v0.16b, v3.16b
aese v1.16b, v3.16b
aesmc v0.16b, v0.16b
aesmc v1.16b, v1.16b
ld1 {v5.2d}, [x10], #16 /* load next round key */
bpl 2b
aese v0.16b, v4.16b
aese v1.16b, v4.16b
subs w2, w2, #16
bmi 6f /* partial block? */
ld1 {v2.16b}, [x1], #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}, [x0], #16 /* write output block */
bne 0b
rev x8, x8
st1 {v0.2d}, [x5] /* store mac */
str x8, [x6, #8] /* store lsb end of ctr (BE) */
5: ret
6: eor v0.16b, v0.16b, v5.16b /* final round mac */
eor v1.16b, v1.16b, v5.16b /* final round enc */
st1 {v0.2d}, [x5] /* store mac */
add w2, w2, #16 /* process partial tail block */
7: ldrb w9, [x1], #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, [x0], #1 /* store out byte */
strb w7, [x5], #1 /* store mac byte */
subs w2, w2, #1
beq 5b
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 7b
.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)