fr_sha1.c   [plain text]

```/*
*  SHA-1 in C
*  By Steve Reid <steve@edmweb.com>
*  100% Public Domain
*
*  Version:	\$Id: sha1.c,v 1.13 2008/06/05 12:07:22 aland Exp \$
*/

#include "fr_sha1.h"
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#define EXTERN	__private_extern__

#define blk0(i) (block->l[i] = htonl(block->l[i]))

#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))

/* blk0() and blk() perform the initial expand. */
/* I got the idea of expanding during the round function from SSLeay */

#define blk0(i) (block->l[i] = htonl(block->l[i]))

#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
^block->l[(i+2)&15]^block->l[i&15],1))

/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);

/* Hash a single 512-bit block. This is the core of the algorithm. */
EXTERN
void fr_SHA1Transform(fr_SHA1_CTX * context, const uint8_t buffer[64])
{
uint32_t a, b, c, d, e;
typedef union {
uint8_t c[64];
uint32_t l[16];
} CHAR64LONG16;
CHAR64LONG16 *block;
CHAR64LONG16 workspace;
uint32_t * state = context->state;

block = &workspace;
memcpy(block, buffer, 64);
/* Copy context->state[] to working vars */
a = state[0];
b = state[1];
c = state[2];
d = state[3];
e = state[4];
/* 4 rounds of 20 operations each. Loop unrolled. */
R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);
R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);
R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);
R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);
R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);
R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);
/* Add the working vars back into context.state[] */
context->state[0] += a;
context->state[1] += b;
context->state[2] += c;
context->state[3] += d;
context->state[4] += e;
/* Wipe variables */
/* a = b = c = d = e = 0; */
}

/* fr_SHA1Init - Initialize new context */
EXTERN
void fr_SHA1Init(fr_SHA1_CTX* context)
{
/* SHA1 initialization constants */
context->state[0] = 0x67452301;
context->state[1] = 0xEFCDAB89;
context->state[3] = 0x10325476;
context->state[4] = 0xC3D2E1F0;
context->count[0] = context->count[1] = 0;
}

/* Run your data through this. */
#if 0
void fr_SHA1Update(fr_SHA1_CTX* context, const uint8_t* data, unsigned int len)
{
unsigned int i, j;

j = (context->count[0] >> 3) & 63;
if ((context->count[0] += len << 3) < (len << 3)) context->count[1]++;
context->count[1] += (len >> 29);
if ((j + len) > 63) {
memcpy(&context->buffer[j], data, (i = 64-j));
fr_SHA1Transform(context, context->buffer);
for ( ; i + 63 < len; i += 64) {
fr_SHA1Transform(context, &data[i]);
}
j = 0;
}
else i = 0;
memcpy(&context->buffer[j], &data[i], len - i);
}

void fr_SHA1Final(uint8_t digest[20], fr_SHA1_CTX* context)
{
uint32_t i, j;
uint8_t finalcount[8];

for (i = 0; i < 8; i++) {
finalcount[i] = (uint8_t)((context->count[(i >= 4 ? 0 : 1)]
>> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
}
fr_SHA1Update(context, (const unsigned char *) "\200", 1);
while ((context->count[0] & 504) != 448) {
fr_SHA1Update(context, (const unsigned char *) "\0", 1);
}
fr_SHA1Update(context, finalcount, 8);  /* Should cause a fr_SHA1Transform() */
for (i = 0; i < 20; i++) {
digest[i] = (uint8_t)
((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
}
/* Wipe variables */
i = j = 0;
memset(context->buffer, 0, 64);
memset(context->state, 0, 20);
memset(context->count, 0, 8);
memset(&finalcount, 0, 8);
}
#endif /* 0 */

EXTERN
void fr_SHA1FinalNoLen(uint8_t digest[20], fr_SHA1_CTX* context)
{
uint32_t i;

for (i = 0; i < 20; i++) {
digest[i] = (uint8_t)
((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
}

/* Wipe variables */
memset(context->buffer, 0, 64);
memset(context->state, 0, 20);
memset(context->count, 0, 8);
}
```