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arm: remove "optimized" SHA1 routines

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Since commit 1eb19a12bd ("lib/sha1: use the git implementation of
SHA-1"), the ARM SHA1 routines no longer work.  The reason? They
depended on the larger 320-byte workspace, and now the sha1 workspace is
just 16 words (64 bytes).  So the assembly version would overwrite the
stack randomly.

The optimized asm version is also probably slower than the new improved
C version, so there's no reason to keep it around.  At least that was
the case in git, where what appears to be the same assembly language
version was removed two years ago because the optimized C BLK_SHA1 code
was faster.

Reported-and-tested-by: Joachim Eastwood <manabian@gmail.com>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Linus Torvalds 2011-08-07 14:07:03 -07:00
parent 3295514841
commit 4d4487140d
2 changed files with 1 additions and 212 deletions
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2
arch/arm/lib/Makefile
View File

@ -12,7 +12,7 @@ lib-y := backtrace.o changebit.o csumipv6.o csumpartial.o \
strchr.o strrchr.o \
testchangebit.o testclearbit.o testsetbit.o \
ashldi3.o ashrdi3.o lshrdi3.o muldi3.o \
ucmpdi2.o lib1funcs.o div64.o sha1.o \
ucmpdi2.o lib1funcs.o div64.o \
io-readsb.o io-writesb.o io-readsl.o io-writesl.o
mmu-y := clear_user.o copy_page.o getuser.o putuser.o

211
arch/arm/lib/sha1.S
View File

@ -1,211 +0,0 @@
/*
* linux/arch/arm/lib/sha1.S
*
* SHA transform optimized for ARM
*
* Copyright: (C) 2005 by Nicolas Pitre <nico@fluxnic.net>
* 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)
.align 2
.L_sha_K:
.word 0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6
/*
* void sha_init(__u32 *buf)
*/
.align 2
.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)