/*
* linux/arch/arm/lib/sha1.S
*
* SHA transform optimized for ARM
*
* Copyright: (C) 2005 by Nicolas Pitre <nico@cam.org>
* Created: September 17, 2005
*
* 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.
*
* The reference implementation for this code is linux/lib/sha1.c
*/
#include <linux/linkage.h>
.text
/*
* void sha_transform(__u32 *digest, const char *in, __u32 *W)
*
* Note: the "in" ptr may be unaligned.
*/
ENTRY(sha_transform)
stmfd sp!, {r4 - r8, lr}
@ for (i = 0; i < 16; i++)
@ W[i] = be32_to_cpu(in[i]);
#ifdef __ARMEB__
mov r4, r0
mov r0, r2
mov r2, #64
bl memcpy
mov r2, r0
mov r0, r4
#else
mov r3, r2
mov lr, #16
1: ldrb r4, [r1], #1
ldrb r5, [r1], #1
ldrb r6, [r1], #1
ldrb r7, [r1], #1
subs lr, lr, #1
orr r5, r5, r4, lsl #8
orr r6, r6, r5, lsl #8
orr r7, r7, r6, lsl #8
str r7, [r3], #4
bne 1b
#endif
@ for (i = 0; i < 64; i++)
@ W[i+16] = ror(W[i+13] ^ W[i+8] ^ W[i+2] ^ W[i], 31);
sub r3, r2, #4
mov lr, #64
2: ldr r4, [r3, #4]!
subs lr, lr, #1
ldr r5, [r3, #8]
ldr r6, [r3, #32]
ldr r7, [r3, #52]
eor r4, r4, r5
eor r4, r4, r6
eor r4, r4, r7
mov r4, r4, ror #31
str r4, [r3, #64]
bne 2b
/*
* The SHA functions are:
*
* f1(B,C,D) = (D ^ (B & (C ^ D)))
* f2(B,C,D) = (B ^ C ^ D)
* f3(B,C,D) = ((B & C) | (D & (B | C)))
*
* Then the sub-blocks are processed as follows:
*
* A' = ror(A, 27) + f(B,C,D) + E + K + *W++
* B' = A
* C' = ror(B, 2)
* D' = C
* E' = D
*
* We therefore unroll each loop 5 times to avoid register shuffling.
* Also the ror for C (and also D and E which are successivelyderived
* from it) is applied in place to cut on an additional mov insn for
* each round.
*/
.macro sha_f1, A, B, C, D, E
ldr r3, [r2], #4
eor ip, \C, \D
add \E, r1, \E, ror #2
and ip, \B, ip, ror #2
add \E, \E, \A, ror #27
eor ip, ip, \D, ror #2
add \E, \E, r3
add \E, \E, ip
.endm
.macro sha_f2, A, B, C, D, E
ldr r3, [r2], #4
add \E, r1, \E, ror #2
eor ip, \B, \C, ror #2
add \E, \E, \A, ror #27
eor ip, ip, \D, ror #2
add \E, \E, r3
add \E, \E, ip
.endm
.macro sha_f3, A, B, C, D, E
ldr r3, [r2], #4
add \E, r1, \E, ror #2
orr ip, \B, \C, ror #2
add \E, \E, \A, ror #27
and ip, ip, \D, ror #2
add \E, \E, r3
and r3, \B, \C, ror #2
orr ip, ip, r3
add \E, \E, ip
.endm
ldmia r0, {r4 - r8}
mov lr, #4
ldr r1, .L_sha_K + 0
/* adjust initial values */
mov r6, r6, ror #30
mov r7, r7, ror #30
mov r8, r8, ror #30
3: subs lr, lr, #1
sha_f1 r4, r5, r6, r7, r8
sha_f1 r8, r4, r5, r6, r7
sha_f1 r7, r8, r4, r5, r6
sha_f1 r6, r7, r8, r4, r5
sha_f1 r5, r6, r7, r8, r4
bne 3b
ldr r1, .L_sha_K + 4
mov lr, #4
4: subs lr, lr, #1
sha_f2 r4, r5, r6, r7, r8
sha_f2 r8, r4, r5, r6, r7
sha_f2 r7, r8, r4, r5, r6
sha_f2 r6, r7, r8, r4, r5
sha_f2 r5, r6, r7, r8, r4
bne 4b
ldr r1, .L_sha_K + 8
mov lr, #4
5: subs lr, lr, #1
sha_f3 r4, r5, r6, r7, r8
sha_f3 r8, r4, r5, r6, r7
sha_f3 r7, r8, r4, r5, r6
sha_f3 r6, r7, r8, r4, r5
sha_f3 r5, r6, r7, r8, r4
bne 5b
ldr r1, .L_sha_K + 12
mov lr, #4
6: subs lr, lr, #1
sha_f2 r4, r5, r6, r7, r8
sha_f2 r8, r4, r5, r6, r7
sha_f2 r7, r8, r4, r5, r6
sha_f2 r6, r7, r8, r4, r5
sha_f2 r5, r6, r7, r8, r4
bne 6b
ldmia r0, {r1, r2, r3, ip, lr}
add r4, r1, r4
add r5, r2, r5
add r6, r3, r6, ror #2
add r7, ip, r7, ror #2
add r8, lr, r8, ror #2
stmia r0, {r4 - r8}
ldmfd sp!, {r4 - r8, pc}
ENDPROC(sha_transform)
.L_sha_K:
.word 0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6
/*
* void sha_init(__u32 *buf)
*/
.L_sha_initial_digest:
.word 0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0
ENTRY(sha_init)
str lr, [sp, #-4]!
adr r1, .L_sha_initial_digest
ldmia r1, {r1, r2, r3, ip, lr}
stmia r0, {r1, r2, r3, ip, lr}
ldr pc, [sp], #4
ENDPROC(sha_init)
