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73 lines
1.4 KiB
C
73 lines
1.4 KiB
C
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/*
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* SHA-1 implementation.
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*
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* Copyright (C) 2005 Paul Mackerras <paulus@samba.org>
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*
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* This version assumes we are running on a big-endian machine.
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* It calls an external sha1_core() to process blocks of 64 bytes.
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*/
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#include <stdio.h>
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#include <string.h>
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#include "sha1.h"
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extern void sha1_core(uint32_t *hash, const unsigned char *p,
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unsigned int nblocks);
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int SHA1_Init(SHA_CTX *c)
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{
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c->hash[0] = 0x67452301;
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c->hash[1] = 0xEFCDAB89;
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c->hash[2] = 0x98BADCFE;
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c->hash[3] = 0x10325476;
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c->hash[4] = 0xC3D2E1F0;
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c->len = 0;
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c->cnt = 0;
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return 0;
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}
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int SHA1_Update(SHA_CTX *c, const void *ptr, unsigned long n)
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{
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unsigned long nb;
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const unsigned char *p = ptr;
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c->len += n << 3;
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while (n != 0) {
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if (c->cnt || n < 64) {
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nb = 64 - c->cnt;
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if (nb > n)
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nb = n;
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memcpy(&c->buf.b[c->cnt], p, nb);
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if ((c->cnt += nb) == 64) {
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sha1_core(c->hash, c->buf.b, 1);
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c->cnt = 0;
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}
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} else {
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nb = n >> 6;
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sha1_core(c->hash, p, nb);
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nb <<= 6;
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}
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n -= nb;
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p += nb;
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}
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return 0;
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}
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int SHA1_Final(unsigned char *hash, SHA_CTX *c)
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{
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unsigned int cnt = c->cnt;
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c->buf.b[cnt++] = 0x80;
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if (cnt > 56) {
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if (cnt < 64)
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memset(&c->buf.b[cnt], 0, 64 - cnt);
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sha1_core(c->hash, c->buf.b, 1);
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cnt = 0;
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}
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if (cnt < 56)
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memset(&c->buf.b[cnt], 0, 56 - cnt);
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c->buf.l[7] = c->len;
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sha1_core(c->hash, c->buf.b, 1);
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memcpy(hash, c->hash, 20);
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return 0;
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}
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