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Diffstat (limited to 'code/qcommon/md4.c')
| -rw-r--r-- | code/qcommon/md4.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/code/qcommon/md4.c b/code/qcommon/md4.c new file mode 100644 index 0000000..838b062 --- /dev/null +++ b/code/qcommon/md4.c @@ -0,0 +1,208 @@ +/* + mdfour.c + + An implementation of MD4 designed for use in the samba SMB + authentication protocol + + Copyright (C) 1997-1998 Andrew Tridgell + + 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: + + Free Software Foundation, Inc. + 59 Temple Place - Suite 330 + Boston, MA 02111-1307, USA + + $Id: mdfour.c,v 1.1 2002/08/23 22:03:27 abster Exp $ +*/ + +#include "q_shared.h" +#include "qcommon.h" + +struct mdfour { + uint32_t A, B, C, D; + uint32_t totalN; +}; + + +/* NOTE: This code makes no attempt to be fast! + + It assumes that a int is at least 32 bits long +*/ + +static struct mdfour *m; + +#define F(X,Y,Z) (((X)&(Y)) | ((~(X))&(Z))) +#define G(X,Y,Z) (((X)&(Y)) | ((X)&(Z)) | ((Y)&(Z))) +#define H(X,Y,Z) ((X)^(Y)^(Z)) +#define lshift(x,s) (((x)<<(s)) | ((x)>>(32-(s)))) + +#define ROUND1(a,b,c,d,k,s) a = lshift(a + F(b,c,d) + X[k], s) +#define ROUND2(a,b,c,d,k,s) a = lshift(a + G(b,c,d) + X[k] + 0x5A827999,s) +#define ROUND3(a,b,c,d,k,s) a = lshift(a + H(b,c,d) + X[k] + 0x6ED9EBA1,s) + +/* this applies md4 to 64 byte chunks */ +static void mdfour64(uint32_t *M) +{ + int j; + uint32_t AA, BB, CC, DD; + uint32_t X[16]; + uint32_t A,B,C,D; + + for (j=0;j<16;j++) + X[j] = M[j]; + + A = m->A; B = m->B; C = m->C; D = m->D; + AA = A; BB = B; CC = C; DD = D; + + ROUND1(A,B,C,D, 0, 3); ROUND1(D,A,B,C, 1, 7); + ROUND1(C,D,A,B, 2, 11); ROUND1(B,C,D,A, 3, 19); + ROUND1(A,B,C,D, 4, 3); ROUND1(D,A,B,C, 5, 7); + ROUND1(C,D,A,B, 6, 11); ROUND1(B,C,D,A, 7, 19); + ROUND1(A,B,C,D, 8, 3); ROUND1(D,A,B,C, 9, 7); + ROUND1(C,D,A,B, 10, 11); ROUND1(B,C,D,A, 11, 19); + ROUND1(A,B,C,D, 12, 3); ROUND1(D,A,B,C, 13, 7); + ROUND1(C,D,A,B, 14, 11); ROUND1(B,C,D,A, 15, 19); + + ROUND2(A,B,C,D, 0, 3); ROUND2(D,A,B,C, 4, 5); + ROUND2(C,D,A,B, 8, 9); ROUND2(B,C,D,A, 12, 13); + ROUND2(A,B,C,D, 1, 3); ROUND2(D,A,B,C, 5, 5); + ROUND2(C,D,A,B, 9, 9); ROUND2(B,C,D,A, 13, 13); + ROUND2(A,B,C,D, 2, 3); ROUND2(D,A,B,C, 6, 5); + ROUND2(C,D,A,B, 10, 9); ROUND2(B,C,D,A, 14, 13); + ROUND2(A,B,C,D, 3, 3); ROUND2(D,A,B,C, 7, 5); + ROUND2(C,D,A,B, 11, 9); ROUND2(B,C,D,A, 15, 13); + + ROUND3(A,B,C,D, 0, 3); ROUND3(D,A,B,C, 8, 9); + ROUND3(C,D,A,B, 4, 11); ROUND3(B,C,D,A, 12, 15); + ROUND3(A,B,C,D, 2, 3); ROUND3(D,A,B,C, 10, 9); + ROUND3(C,D,A,B, 6, 11); ROUND3(B,C,D,A, 14, 15); + ROUND3(A,B,C,D, 1, 3); ROUND3(D,A,B,C, 9, 9); + ROUND3(C,D,A,B, 5, 11); ROUND3(B,C,D,A, 13, 15); + ROUND3(A,B,C,D, 3, 3); ROUND3(D,A,B,C, 11, 9); + ROUND3(C,D,A,B, 7, 11); ROUND3(B,C,D,A, 15, 15); + + A += AA; B += BB; C += CC; D += DD; + + for (j=0;j<16;j++) + X[j] = 0; + + m->A = A; m->B = B; m->C = C; m->D = D; +} + +static void copy64(uint32_t *M, byte *in) +{ + int i; + + for (i=0;i<16;i++) + M[i] = (in[i*4+3]<<24) | (in[i*4+2]<<16) | + (in[i*4+1]<<8) | (in[i*4+0]<<0); +} + +static void copy4(byte *out,uint32_t x) +{ + out[0] = x&0xFF; + out[1] = (x>>8)&0xFF; + out[2] = (x>>16)&0xFF; + out[3] = (x>>24)&0xFF; +} + +void mdfour_begin(struct mdfour *md) +{ + md->A = 0x67452301; + md->B = 0xefcdab89; + md->C = 0x98badcfe; + md->D = 0x10325476; + md->totalN = 0; +} + + +static void mdfour_tail(byte *in, int n) +{ + byte buf[128]; + uint32_t M[16]; + uint32_t b; + + m->totalN += n; + + b = m->totalN * 8; + + Com_Memset(buf, 0, 128); + if (n) Com_Memcpy(buf, in, n); + buf[n] = 0x80; + + if (n <= 55) { + copy4(buf+56, b); + copy64(M, buf); + mdfour64(M); + } else { + copy4(buf+120, b); + copy64(M, buf); + mdfour64(M); + copy64(M, buf+64); + mdfour64(M); + } +} + +static void mdfour_update(struct mdfour *md, byte *in, int n) +{ + uint32_t M[16]; + + m = md; + + if (n == 0) mdfour_tail(in, n); + + while (n >= 64) { + copy64(M, in); + mdfour64(M); + in += 64; + n -= 64; + m->totalN += 64; + } + + mdfour_tail(in, n); +} + + +static void mdfour_result(struct mdfour *md, byte *out) +{ + m = md; + + copy4(out, m->A); + copy4(out+4, m->B); + copy4(out+8, m->C); + copy4(out+12, m->D); +} + +static void mdfour(byte *out, byte *in, int n) +{ + struct mdfour md; + mdfour_begin(&md); + mdfour_update(&md, in, n); + mdfour_result(&md, out); +} + +//=================================================================== + +unsigned Com_BlockChecksum (const void *buffer, int length) +{ + int digest[4]; + unsigned val; + + mdfour( (byte *)digest, (byte *)buffer, length ); + + val = digest[0] ^ digest[1] ^ digest[2] ^ digest[3]; + + return val; +} |