mirror of http://galexander.org/git/simplesshd.git
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.
132 lines
2.7 KiB
132 lines
2.7 KiB
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
|
|
*
|
|
* LibTomCrypt is a library that provides various cryptographic
|
|
* algorithms in a highly modular and flexible manner.
|
|
*
|
|
* The library is free for all purposes without any express
|
|
* guarantee it works.
|
|
*/
|
|
#include "tomcrypt.h"
|
|
|
|
/**
|
|
@file adler32.c
|
|
Adler-32 checksum algorithm
|
|
Written and placed in the public domain by Wei Dai
|
|
Adapted for libtomcrypt by Steffen Jaeckel
|
|
*/
|
|
#ifdef LTC_ADLER32
|
|
|
|
static const unsigned long _adler32_base = 65521;
|
|
|
|
void adler32_init(adler32_state *ctx)
|
|
{
|
|
LTC_ARGCHKVD(ctx != NULL);
|
|
ctx->s[0] = 1;
|
|
ctx->s[1] = 0;
|
|
}
|
|
|
|
void adler32_update(adler32_state *ctx, const unsigned char *input, unsigned long length)
|
|
{
|
|
unsigned long s1, s2;
|
|
|
|
LTC_ARGCHKVD(ctx != NULL);
|
|
LTC_ARGCHKVD(input != NULL);
|
|
s1 = ctx->s[0];
|
|
s2 = ctx->s[1];
|
|
|
|
if (length % 8 != 0) {
|
|
do {
|
|
s1 += *input++;
|
|
s2 += s1;
|
|
length--;
|
|
} while (length % 8 != 0);
|
|
|
|
if (s1 >= _adler32_base)
|
|
s1 -= _adler32_base;
|
|
s2 %= _adler32_base;
|
|
}
|
|
|
|
while (length > 0) {
|
|
s1 += input[0];
|
|
s2 += s1;
|
|
s1 += input[1];
|
|
s2 += s1;
|
|
s1 += input[2];
|
|
s2 += s1;
|
|
s1 += input[3];
|
|
s2 += s1;
|
|
s1 += input[4];
|
|
s2 += s1;
|
|
s1 += input[5];
|
|
s2 += s1;
|
|
s1 += input[6];
|
|
s2 += s1;
|
|
s1 += input[7];
|
|
s2 += s1;
|
|
|
|
length -= 8;
|
|
input += 8;
|
|
|
|
if (s1 >= _adler32_base)
|
|
s1 -= _adler32_base;
|
|
s2 %= _adler32_base;
|
|
}
|
|
|
|
LTC_ARGCHKVD(s1 < _adler32_base);
|
|
LTC_ARGCHKVD(s2 < _adler32_base);
|
|
|
|
ctx->s[0] = (unsigned short)s1;
|
|
ctx->s[1] = (unsigned short)s2;
|
|
}
|
|
|
|
void adler32_finish(adler32_state *ctx, void *hash, unsigned long size)
|
|
{
|
|
unsigned char* h;
|
|
|
|
LTC_ARGCHKVD(ctx != NULL);
|
|
LTC_ARGCHKVD(hash != NULL);
|
|
|
|
h = hash;
|
|
|
|
switch (size) {
|
|
default:
|
|
h[3] = ctx->s[0] & 0x0ff;
|
|
/* FALLTHROUGH */
|
|
case 3:
|
|
h[2] = (ctx->s[0] >> 8) & 0x0ff;
|
|
/* FALLTHROUGH */
|
|
case 2:
|
|
h[1] = ctx->s[1] & 0x0ff;
|
|
/* FALLTHROUGH */
|
|
case 1:
|
|
h[0] = (ctx->s[1] >> 8) & 0x0ff;
|
|
/* FALLTHROUGH */
|
|
case 0:
|
|
;
|
|
}
|
|
}
|
|
|
|
int adler32_test(void)
|
|
{
|
|
#ifndef LTC_TEST
|
|
return CRYPT_NOP;
|
|
#else
|
|
const void* in = "libtomcrypt";
|
|
const unsigned char adler32[] = { 0x1b, 0xe8, 0x04, 0xba };
|
|
unsigned char out[4];
|
|
adler32_state ctx;
|
|
adler32_init(&ctx);
|
|
adler32_update(&ctx, in, strlen(in));
|
|
adler32_finish(&ctx, out, 4);
|
|
if (compare_testvector(adler32, 4, out, 4, "adler32", 0)) {
|
|
return CRYPT_FAIL_TESTVECTOR;
|
|
}
|
|
return CRYPT_OK;
|
|
#endif
|
|
}
|
|
#endif
|
|
|
|
/* ref: $Format:%D$ */
|
|
/* git commit: $Format:%H$ */
|
|
/* commit time: $Format:%ai$ */
|