/**
* sha1.c: this file provides the sha1 hashing algorithm
* based in part on code in the public domain by Niyaz PK.
* -- coded by Ajandurah@Demonslair 21/02/08
*/
#include <math.h>
#ifdef LATTICE
#include "/lpc_incl.h"
#else
#include "../lpc_incl.h"
#include "../efun_protos.h"
#endif
#define rotateleft(x,n) ((x<<n) | (x>>(32-n)))
#define rotateright(x,n) ((x>>n) | (x<<(32-n)))
#ifdef F_SHA1
void f_sha1(void)
{
unsigned long int h0,h1,h2,h3,h4,a,b,c,d,e,f,k,temp;
int i, j, m;
h0 = 0x67452301;
h1 = 0xEFCDAB89;
h2 = 0x98BADCFE;
h3 = 0x10325476;
h4 = 0xC3D2E1F0;
unsigned char *str;
str = (unsigned char *)malloc(SVALUE_STRLEN(sp)+100);
strcpy((char *)str, (const char *)sp->u.string);
int current_length = strlen((const char *)str);
int original_length = current_length;
str[current_length] = 0x80;
str[current_length + 1] = '\0';
char ic = str[current_length];
current_length++;
int ib = current_length % 64;
if (ib < 56)
ib = 56 - ib;
else
ib = 120 - ib;
for (i=0; i<ib; i++)
{
str[current_length] = 0x00;
current_length++;
}
str[current_length + 1] = '\0';
for (i=0; i<6; i++)
{
str[current_length] = 0x0;
current_length++;
}
str[current_length] = (original_length * 8) / 0x100;
current_length++;
str[current_length] = (original_length * 8) % 0x100;
current_length++;
str[current_length + i] = '\0';
int number_of_chunks = current_length / 64;
unsigned long int word[80];
for (i=0; i<number_of_chunks; i++)
{
for (j=0; j<16; j++)
{
word[j] = str[i*64+j*4+0] * 0x1000000 + str[i*64+j*4+1] * 0x10000 + str[i*64+j*4+2] * 0x100 + str[i*64+j*4+3];
}
for (j=16; j<80; j++)
{
word[j] = rotateleft((word[j-3] ^ word[j-8] ^ word[j-14] ^ word[j-16]),1);
}
a = h0;
b = h1;
c = h2;
d = h3;
e = h4;
for (m=0; m<80; m++)
{
if (m <= 19)
{
f = (b & c) | ((~b) & d);
k = 0x5A827999;
}
else if (m <= 39)
{
f = b ^ c ^ d;
k = 0x6ED9EBA1;
}
else if (m <= 59)
{
f = (b & c) | (b & d) | (c & d);
k = 0x8F1BBCDC;
}
else
{
f = b ^ c ^ d;
k = 0xCA62C1D6;
}
temp = (rotateleft(a, 5) + f + e + k + word[m]) & 0xFFFFFFFF;
e = d;
d = c;
c = rotateleft(b, 30);
b = a;
a = temp;
}
h0 = h0 + a;
h1 = h1 + b;
h2 = h2 + c;
h3 = h3 + d;
h4 = h4 + e;
}
sprintf(str, "%x%x%x%x%x", h0, h1, h2, h3, h4);
pop_stack();
push_malloced_string(string_copy(str, "f_sha1"));
free(str);
}
#endif
