mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
137 lines
4.4 KiB
137 lines
4.4 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* SHA1 routine optimized to do word accesses rather than byte accesses, |
|
* and to avoid unnecessary copies into the context array. |
|
* |
|
* This was based on the git SHA1 implementation. |
|
*/ |
|
|
|
#include <linux/kernel.h> |
|
#include <linux/export.h> |
|
#include <linux/bitops.h> |
|
#include <linux/string.h> |
|
#include <crypto/sha1.h> |
|
#include <asm/unaligned.h> |
|
|
|
/* |
|
* If you have 32 registers or more, the compiler can (and should) |
|
* try to change the array[] accesses into registers. However, on |
|
* machines with less than ~25 registers, that won't really work, |
|
* and at least gcc will make an unholy mess of it. |
|
* |
|
* So to avoid that mess which just slows things down, we force |
|
* the stores to memory to actually happen (we might be better off |
|
* with a 'W(t)=(val);asm("":"+m" (W(t))' there instead, as |
|
* suggested by Artur Skawina - that will also make gcc unable to |
|
* try to do the silly "optimize away loads" part because it won't |
|
* see what the value will be). |
|
* |
|
* Ben Herrenschmidt reports that on PPC, the C version comes close |
|
* to the optimized asm with this (ie on PPC you don't want that |
|
* 'volatile', since there are lots of registers). |
|
* |
|
* On ARM we get the best code generation by forcing a full memory barrier |
|
* between each SHA_ROUND, otherwise gcc happily get wild with spilling and |
|
* the stack frame size simply explode and performance goes down the drain. |
|
*/ |
|
|
|
#ifdef CONFIG_X86 |
|
#define setW(x, val) (*(volatile __u32 *)&W(x) = (val)) |
|
#elif defined(CONFIG_ARM) |
|
#define setW(x, val) do { W(x) = (val); __asm__("":::"memory"); } while (0) |
|
#else |
|
#define setW(x, val) (W(x) = (val)) |
|
#endif |
|
|
|
/* This "rolls" over the 512-bit array */ |
|
#define W(x) (array[(x)&15]) |
|
|
|
/* |
|
* Where do we get the source from? The first 16 iterations get it from |
|
* the input data, the next mix it from the 512-bit array. |
|
*/ |
|
#define SHA_SRC(t) get_unaligned_be32((__u32 *)data + t) |
|
#define SHA_MIX(t) rol32(W(t+13) ^ W(t+8) ^ W(t+2) ^ W(t), 1) |
|
|
|
#define SHA_ROUND(t, input, fn, constant, A, B, C, D, E) do { \ |
|
__u32 TEMP = input(t); setW(t, TEMP); \ |
|
E += TEMP + rol32(A,5) + (fn) + (constant); \ |
|
B = ror32(B, 2); \ |
|
TEMP = E; E = D; D = C; C = B; B = A; A = TEMP; } while (0) |
|
|
|
#define T_0_15(t, A, B, C, D, E) SHA_ROUND(t, SHA_SRC, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E ) |
|
#define T_16_19(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E ) |
|
#define T_20_39(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) , 0x6ed9eba1, A, B, C, D, E ) |
|
#define T_40_59(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, ((B&C)+(D&(B^C))) , 0x8f1bbcdc, A, B, C, D, E ) |
|
#define T_60_79(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) , 0xca62c1d6, A, B, C, D, E ) |
|
|
|
/** |
|
* sha1_transform - single block SHA1 transform (deprecated) |
|
* |
|
* @digest: 160 bit digest to update |
|
* @data: 512 bits of data to hash |
|
* @array: 16 words of workspace (see note) |
|
* |
|
* This function executes SHA-1's internal compression function. It updates the |
|
* 160-bit internal state (@digest) with a single 512-bit data block (@data). |
|
* |
|
* Don't use this function. SHA-1 is no longer considered secure. And even if |
|
* you do have to use SHA-1, this isn't the correct way to hash something with |
|
* SHA-1 as this doesn't handle padding and finalization. |
|
* |
|
* Note: If the hash is security sensitive, the caller should be sure |
|
* to clear the workspace. This is left to the caller to avoid |
|
* unnecessary clears between chained hashing operations. |
|
*/ |
|
void sha1_transform(__u32 *digest, const char *data, __u32 *array) |
|
{ |
|
__u32 A, B, C, D, E; |
|
unsigned int i = 0; |
|
|
|
A = digest[0]; |
|
B = digest[1]; |
|
C = digest[2]; |
|
D = digest[3]; |
|
E = digest[4]; |
|
|
|
/* Round 1 - iterations 0-16 take their input from 'data' */ |
|
for (; i < 16; ++i) |
|
T_0_15(i, A, B, C, D, E); |
|
|
|
/* Round 1 - tail. Input from 512-bit mixing array */ |
|
for (; i < 20; ++i) |
|
T_16_19(i, A, B, C, D, E); |
|
|
|
/* Round 2 */ |
|
for (; i < 40; ++i) |
|
T_20_39(i, A, B, C, D, E); |
|
|
|
/* Round 3 */ |
|
for (; i < 60; ++i) |
|
T_40_59(i, A, B, C, D, E); |
|
|
|
/* Round 4 */ |
|
for (; i < 80; ++i) |
|
T_60_79(i, A, B, C, D, E); |
|
|
|
digest[0] += A; |
|
digest[1] += B; |
|
digest[2] += C; |
|
digest[3] += D; |
|
digest[4] += E; |
|
} |
|
EXPORT_SYMBOL(sha1_transform); |
|
|
|
/** |
|
* sha1_init - initialize the vectors for a SHA1 digest |
|
* @buf: vector to initialize |
|
*/ |
|
void sha1_init(__u32 *buf) |
|
{ |
|
buf[0] = 0x67452301; |
|
buf[1] = 0xefcdab89; |
|
buf[2] = 0x98badcfe; |
|
buf[3] = 0x10325476; |
|
buf[4] = 0xc3d2e1f0; |
|
} |
|
EXPORT_SYMBOL(sha1_init);
|
|
|