busybox/coreutils/sha1sum.c
2003-03-19 09:13:01 +00:00

225 lines
5.1 KiB
C

/*
* Based on shasum from http://www.netsw.org/crypto/hash/
*
* shasum fixed with reference to coreutils and the nist fip180-1 document
* which is incorrect, in section 5
* - ft(B,C,D) = (B AND C) OR ((NOT B) AND D) ( 0 <= t <= 19)
* + ft(B,C,D) = (D XOR (B AND (C XOR S))) ( 0 <= t <= 19)
*
* Copyright (C) 1999 Scott G. Miller
* Copyright (C) 2003 Glenn L. McGrath
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <stdio.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <endian.h>
#include "busybox.h"
#if __BYTE_ORDER == __BIG_ENDIAN
# define SWAP(n) (n)
#else
# define SWAP(n) \
(((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
#endif
#define f1(X,Y,Z) (Z ^ (X & (Y ^ Z)))
#define f2(X,Y,Z) (X ^ Y ^ Z)
#define f3(X,Y,Z) ((X & Y) | (Z & (X | Y)))
#define rol1(x) (x<<1) | ((x>>31) & 1)
#define rol5(x) ((x<<5) | ((x>>27) & 0x1f))
#define rol30(x) (x<<30) | ((x>>2) & 0x3fffffff)
static void sha_hash(unsigned int *data, int *hash)
{
RESERVE_CONFIG_BUFFER(word, 80 * sizeof(unsigned int));
int *W = (unsigned int *) &word;
int a = hash[0];
int b = hash[1];
int c = hash[2];
int d = hash[3];
int e = hash[4];
int t;
int TEMP;
for (t = 0; t < 16; t++) {
W[t] = SWAP(data[t]);
}
/** Data expansion from 16 to 80 blocks **/
for (t = 16; t < 80; t++) {
int x = W[t - 3] ^ W[t - 8] ^ W[t - 14] ^ W[t - 16];
W[t] = rol1(x);
}
/** Main loops **/
for (t = 0; t < 20; t++) {
TEMP = rol5(a) + f1(b, c, d) + e + W[t] + 0x5a827999;
e = d;
d = c;
c = rol30(b);
b = a;
a = TEMP;
}
for (; t < 40; t++) {
TEMP = rol5(a) + f2(b, c, d) + e + W[t] + 0x6ed9eba1;
e = d;
d = c;
c = rol30(b);
b = a;
a = TEMP;
}
for (; t < 60; t++) {
TEMP = rol5(a) + f3(b, c, d) + e + W[t] + 0x8f1bbcdc;
e = d;
d = c;
c = rol30(b);
b = a;
a = TEMP;
}
for (; t < 80; t++) {
TEMP = rol5(a) + f2(b, c, d) + e + W[t] + 0xca62c1d6;
e = d;
d = c;
c = rol30(b);
b = a;
a = TEMP;
}
RELEASE_CONFIG_BUFFER(word);
hash[0] += a;
hash[1] += b;
hash[2] += c;
hash[3] += d;
hash[4] += e;
}
static void sha1sum_stream(FILE * fd, unsigned int *hashval)
{
RESERVE_CONFIG_BUFFER(buffer, 64);
int length = 0;
hashval[0] = 0x67452301;
hashval[1] = 0xefcdab89;
hashval[2] = 0x98badcfe;
hashval[3] = 0x10325476;
hashval[4] = 0xc3d2e1f0;
while (!feof(fd) && !ferror(fd)) {
int c = fread(&buffer, 1, 64, fd);
length += c;
if (feof(fd) || ferror(fd)) {
int i;
/* If reading from stdin we need to get rid of a tailing character */
if (fd == stdin) {
c--;
length--;
}
for (i = c; i < 61; i++) {
if (i == c) {
buffer[i] = 0x80;
}
else if (i == 60) {
/* This ends up being swaped twice */
((unsigned int *) &buffer)[15] = SWAP(length * 8);
} else {
buffer[i] = 0;
}
}
}
sha_hash((unsigned int *) &buffer, hashval);
}
RELEASE_CONFIG_BUFFER(buffer);
return;
}
static void print_hash(unsigned short hash_length, unsigned int *hash_val, char *filename)
{
int x;
for (x = 0; x < hash_length; x++) {
printf("%08x", hash_val[x]);
}
if (filename != NULL) {
putchar(' ');
putchar(' ');
puts(filename);
}
putchar('\n');
}
/* This should become a common function used by sha1sum and md5sum,
* it needs extra functionality first
*/
extern int authenticate(const int argc, char **argv, void (*hash_ptr)(FILE *stream, unsigned int *hashval), const unsigned short hash_length)
{
int opt;
unsigned int *hashval;
while ((opt = getopt(argc, argv, "sc:w")) != -1) {
switch (opt) {
#if 0
case 's': /* Dont output anything, status code shows success */
break;
case 'c': /* Check a list of checksums against stored values */
break;
case 'w': /* Warn of bad formatting when checking files */
break;
#endif
default:
bb_show_usage();
}
}
hashval = xmalloc(hash_length * sizeof(unsigned int));
if (argc == optind) {
hash_ptr(stdin, hashval);
print_hash(hash_length, hashval, NULL);
} else {
int i;
for (i = optind; i < argc; i++) {
if (!strcmp(argv[i], "-")) {
hash_ptr(stdin, hashval);
print_hash(hash_length, hashval, NULL);
} else {
FILE *stream = bb_xfopen(argv[i], "r");
hash_ptr(stream, hashval);
fclose(stream);
print_hash(hash_length, hashval, argv[i]);
}
}
}
free(hashval);
return 0;
}
extern int sha1sum_main(int argc, char **argv)
{
/* sha1 length is 5 nibbles */
return (authenticate(argc, argv, sha1sum_stream, 5));
}