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mirror of https://gitlab.nic.cz/labs/bird.git synced 2024-12-23 10:11:53 +00:00
bird/lib/sha1.c
2015-04-28 16:58:44 +02:00

341 lines
8.5 KiB
C

/*
* BIRD -- SHA-1 Hash Function (FIPS 180-1, RFC 3174)
*
* (c) 2015 CZ.NIC z.s.p.o.
*
* Based on the code from libucw-6.4
* (c) 2008--2009 Martin Mares <mj@ucw.cz>
*
* Based on the code from libgcrypt-1.2.3, which is
* (c) 1998, 2001, 2002, 2003 Free Software Foundation, Inc.
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include <string.h>
#include "lib/null.h"
#include "lib/sha1.h"
#include "lib/unaligned.h"
void
sha1_init(sha1_context *hd)
{
hd->h0 = 0x67452301;
hd->h1 = 0xefcdab89;
hd->h2 = 0x98badcfe;
hd->h3 = 0x10325476;
hd->h4 = 0xc3d2e1f0;
hd->nblocks = 0;
hd->count = 0;
}
/*
* Transform the message X which consists of 16 32-bit-words
*/
static void
transform(sha1_context *hd, const byte *data)
{
u32 a,b,c,d,e,tm;
u32 x[16];
/* Get values from the chaining vars. */
a = hd->h0;
b = hd->h1;
c = hd->h2;
d = hd->h3;
e = hd->h4;
#ifdef CPU_BIG_ENDIAN
memcpy(x, data, 64);
#else
int i;
for (i = 0; i < 16; i++)
x[i] = get_u32(data+4*i);
#endif
#define K1 0x5A827999L
#define K2 0x6ED9EBA1L
#define K3 0x8F1BBCDCL
#define K4 0xCA62C1D6L
#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 F4(x,y,z) ( x ^ y ^ z )
#define M(i) (tm = x[i&0x0f] ^ x[(i-14)&0x0f] ^ x[(i-8)&0x0f] ^ x[(i-3)&0x0f], (x[i&0x0f] = ROL(tm, 1)))
/** Bitwise rotation of an unsigned int to the left **/
#define ROL(x, bits) (((x) << (bits)) | ((uint)(x) >> (sizeof(uint)*8 - (bits))))
#define R(a, b, c, d, e, f, k, m) \
do \
{ \
e += ROL(a, 5) + f(b, c, d) + k + m; \
b = ROL( b, 30 ); \
} while(0)
R( a, b, c, d, e, F1, K1, x[ 0] );
R( e, a, b, c, d, F1, K1, x[ 1] );
R( d, e, a, b, c, F1, K1, x[ 2] );
R( c, d, e, a, b, F1, K1, x[ 3] );
R( b, c, d, e, a, F1, K1, x[ 4] );
R( a, b, c, d, e, F1, K1, x[ 5] );
R( e, a, b, c, d, F1, K1, x[ 6] );
R( d, e, a, b, c, F1, K1, x[ 7] );
R( c, d, e, a, b, F1, K1, x[ 8] );
R( b, c, d, e, a, F1, K1, x[ 9] );
R( a, b, c, d, e, F1, K1, x[10] );
R( e, a, b, c, d, F1, K1, x[11] );
R( d, e, a, b, c, F1, K1, x[12] );
R( c, d, e, a, b, F1, K1, x[13] );
R( b, c, d, e, a, F1, K1, x[14] );
R( a, b, c, d, e, F1, K1, x[15] );
R( e, a, b, c, d, F1, K1, M(16) );
R( d, e, a, b, c, F1, K1, M(17) );
R( c, d, e, a, b, F1, K1, M(18) );
R( b, c, d, e, a, F1, K1, M(19) );
R( a, b, c, d, e, F2, K2, M(20) );
R( e, a, b, c, d, F2, K2, M(21) );
R( d, e, a, b, c, F2, K2, M(22) );
R( c, d, e, a, b, F2, K2, M(23) );
R( b, c, d, e, a, F2, K2, M(24) );
R( a, b, c, d, e, F2, K2, M(25) );
R( e, a, b, c, d, F2, K2, M(26) );
R( d, e, a, b, c, F2, K2, M(27) );
R( c, d, e, a, b, F2, K2, M(28) );
R( b, c, d, e, a, F2, K2, M(29) );
R( a, b, c, d, e, F2, K2, M(30) );
R( e, a, b, c, d, F2, K2, M(31) );
R( d, e, a, b, c, F2, K2, M(32) );
R( c, d, e, a, b, F2, K2, M(33) );
R( b, c, d, e, a, F2, K2, M(34) );
R( a, b, c, d, e, F2, K2, M(35) );
R( e, a, b, c, d, F2, K2, M(36) );
R( d, e, a, b, c, F2, K2, M(37) );
R( c, d, e, a, b, F2, K2, M(38) );
R( b, c, d, e, a, F2, K2, M(39) );
R( a, b, c, d, e, F3, K3, M(40) );
R( e, a, b, c, d, F3, K3, M(41) );
R( d, e, a, b, c, F3, K3, M(42) );
R( c, d, e, a, b, F3, K3, M(43) );
R( b, c, d, e, a, F3, K3, M(44) );
R( a, b, c, d, e, F3, K3, M(45) );
R( e, a, b, c, d, F3, K3, M(46) );
R( d, e, a, b, c, F3, K3, M(47) );
R( c, d, e, a, b, F3, K3, M(48) );
R( b, c, d, e, a, F3, K3, M(49) );
R( a, b, c, d, e, F3, K3, M(50) );
R( e, a, b, c, d, F3, K3, M(51) );
R( d, e, a, b, c, F3, K3, M(52) );
R( c, d, e, a, b, F3, K3, M(53) );
R( b, c, d, e, a, F3, K3, M(54) );
R( a, b, c, d, e, F3, K3, M(55) );
R( e, a, b, c, d, F3, K3, M(56) );
R( d, e, a, b, c, F3, K3, M(57) );
R( c, d, e, a, b, F3, K3, M(58) );
R( b, c, d, e, a, F3, K3, M(59) );
R( a, b, c, d, e, F4, K4, M(60) );
R( e, a, b, c, d, F4, K4, M(61) );
R( d, e, a, b, c, F4, K4, M(62) );
R( c, d, e, a, b, F4, K4, M(63) );
R( b, c, d, e, a, F4, K4, M(64) );
R( a, b, c, d, e, F4, K4, M(65) );
R( e, a, b, c, d, F4, K4, M(66) );
R( d, e, a, b, c, F4, K4, M(67) );
R( c, d, e, a, b, F4, K4, M(68) );
R( b, c, d, e, a, F4, K4, M(69) );
R( a, b, c, d, e, F4, K4, M(70) );
R( e, a, b, c, d, F4, K4, M(71) );
R( d, e, a, b, c, F4, K4, M(72) );
R( c, d, e, a, b, F4, K4, M(73) );
R( b, c, d, e, a, F4, K4, M(74) );
R( a, b, c, d, e, F4, K4, M(75) );
R( e, a, b, c, d, F4, K4, M(76) );
R( d, e, a, b, c, F4, K4, M(77) );
R( c, d, e, a, b, F4, K4, M(78) );
R( b, c, d, e, a, F4, K4, M(79) );
/* Update chaining vars. */
hd->h0 += a;
hd->h1 += b;
hd->h2 += c;
hd->h3 += d;
hd->h4 += e;
}
/*
* Update the message digest with the contents
* of INBUF with length INLEN.
*/
void
sha1_update(sha1_context *hd, const byte *inbuf, uint inlen)
{
if (hd->count == 64) /* flush the buffer */
{
transform(hd, hd->buf);
hd->count = 0;
hd->nblocks++;
}
if (!inbuf)
return;
if (hd->count)
{
for (; inlen && hd->count < 64; inlen--)
hd->buf[hd->count++] = *inbuf++;
sha1_update( hd, NULL, 0 );
if(!inlen)
return;
}
while (inlen >= 64)
{
transform(hd, inbuf);
hd->count = 0;
hd->nblocks++;
inlen -= 64;
inbuf += 64;
}
for (; inlen && hd->count < 64; inlen--)
hd->buf[hd->count++] = *inbuf++;
}
/*
* The routine final terminates the computation and
* returns the digest.
* The handle is prepared for a new cycle, but adding bytes to the
* handle will the destroy the returned buffer.
* Returns: 20 bytes representing the digest.
*/
byte *
sha1_final(sha1_context *hd)
{
u32 t, msb, lsb;
u32 *p;
sha1_update(hd, NULL, 0); /* flush */;
t = hd->nblocks;
/* multiply by 64 to make a byte count */
lsb = t << 6;
msb = t >> 26;
/* add the count */
t = lsb;
if ((lsb += hd->count) < t)
msb++;
/* multiply by 8 to make a bit count */
t = lsb;
lsb <<= 3;
msb <<= 3;
msb |= t >> 29;
if (hd->count < 56) /* enough room */
{
hd->buf[hd->count++] = 0x80; /* pad */
while (hd->count < 56)
hd->buf[hd->count++] = 0; /* pad */
}
else /* need one extra block */
{
hd->buf[hd->count++] = 0x80; /* pad character */
while (hd->count < 64)
hd->buf[hd->count++] = 0;
sha1_update(hd, NULL, 0); /* flush */;
memset(hd->buf, 0, 56 ); /* fill next block with zeroes */
}
/* append the 64 bit count */
hd->buf[56] = msb >> 24;
hd->buf[57] = msb >> 16;
hd->buf[58] = msb >> 8;
hd->buf[59] = msb ;
hd->buf[60] = lsb >> 24;
hd->buf[61] = lsb >> 16;
hd->buf[62] = lsb >> 8;
hd->buf[63] = lsb ;
transform(hd, hd->buf);
p = (u32*) hd->buf;
#define X(a) do { put_u32(p, hd->h##a); p++; } while(0)
X(0);
X(1);
X(2);
X(3);
X(4);
#undef X
return hd->buf;
}
/*
* Shortcut function which puts the hash value of the supplied buffer
* into outbuf which must have a size of 20 bytes.
*/
void
sha1_hash_buffer(byte *outbuf, const byte *buffer, uint length)
{
sha1_context hd;
sha1_init(&hd);
sha1_update(&hd, buffer, length);
memcpy(outbuf, sha1_final(&hd), SHA1_SIZE);
}
void
sha1_hmac_init(sha1_hmac_context *hd, const byte *key, uint keylen)
{
byte keybuf[SHA1_BLOCK_SIZE], buf[SHA1_BLOCK_SIZE];
// Hash the key if necessary
if (keylen <= SHA1_BLOCK_SIZE)
{
memcpy(keybuf, key, keylen);
bzero(keybuf + keylen, SHA1_BLOCK_SIZE - keylen);
}
else
{
sha1_hash_buffer(keybuf, key, keylen);
bzero(keybuf + SHA1_SIZE, SHA1_BLOCK_SIZE - SHA1_SIZE);
}
// Initialize the inner digest
sha1_init(&hd->ictx);
int i;
for (i = 0; i < SHA1_BLOCK_SIZE; i++)
buf[i] = keybuf[i] ^ 0x36;
sha1_update(&hd->ictx, buf, SHA1_BLOCK_SIZE);
// Initialize the outer digest
sha1_init(&hd->octx);
for (i = 0; i < SHA1_BLOCK_SIZE; i++)
buf[i] = keybuf[i] ^ 0x5c;
sha1_update(&hd->octx, buf, SHA1_BLOCK_SIZE);
}
void
sha1_hmac_update(sha1_hmac_context *hd, const byte *data, uint datalen)
{
// Just update the inner digest
sha1_update(&hd->ictx, data, datalen);
}
byte *sha1_hmac_final(sha1_hmac_context *hd)
{
// Finish the inner digest
byte *isha = sha1_final(&hd->ictx);
// Finish the outer digest
sha1_update(&hd->octx, isha, SHA1_SIZE);
return sha1_final(&hd->octx);
}
void
sha1_hmac(byte *outbuf, const byte *key, uint keylen, const byte *data, uint datalen)
{
sha1_hmac_context hd;
sha1_hmac_init(&hd, key, keylen);
sha1_hmac_update(&hd, data, datalen);
byte *osha = sha1_hmac_final(&hd);
memcpy(outbuf, osha, SHA1_SIZE);
}