+/*
+ 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 7689 2007-11-12 14:28:40Z divverent $
+*/
+
+#include <string.h> /* XoXus: needed for memset call */
+#include "md4.h"
+
+/* 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))
+#ifdef LARGE_INT32
+#define lshift(x,s) ((((x)<<(s))&0xFFFFFFFF) | (((x)>>(32-(s)))&0xFFFFFFFF))
+#else
+#define lshift(x,s) (((x)<<(s)) | ((x)>>(32-(s))))
+#endif
+
+#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 *M)
+{
+ int j;
+ uint32 AA, BB, CC, DD;
+ uint32 X[16];
+ uint32 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;
+
+#ifdef LARGE_INT32
+ A &= 0xFFFFFFFF; B &= 0xFFFFFFFF;
+ C &= 0xFFFFFFFF; D &= 0xFFFFFFFF;
+#endif
+
+ 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 *M, unsigned char *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(unsigned char *out,uint32 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(unsigned char *in, int n)
+{
+ unsigned char buf[128];
+ uint32 M[16];
+ uint32 b;
+
+ m->totalN += n;
+
+ b = m->totalN * 8;
+
+ memset(buf, 0, 128);
+ if (n) 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);
+ }
+}
+
+void mdfour_update(struct mdfour *md, unsigned char *in, int n)
+{
+ uint32 M[16];
+
+// start of edit by Forest 'LordHavoc' Hale
+// commented out to prevent crashing when length is 0
+// if (n == 0) mdfour_tail(in, n);
+// end of edit by Forest 'LordHavoc' Hale
+
+ m = md;
+
+ while (n >= 64) {
+ copy64(M, in);
+ mdfour64(M);
+ in += 64;
+ n -= 64;
+ m->totalN += 64;
+ }
+
+ mdfour_tail(in, n);
+}
+
+
+void mdfour_result(struct mdfour *md, unsigned char *out)
+{
+ m = md;
+
+ copy4(out, m->A);
+ copy4(out+4, m->B);
+ copy4(out+8, m->C);
+ copy4(out+12, m->D);
+}
+
+
+void mdfour(unsigned char *out, unsigned char *in, int n)
+{
+ struct mdfour md;
+ mdfour_begin(&md);
+ mdfour_update(&md, in, n);
+ mdfour_result(&md, out);
+}
+
+///////////////////////////////////////////////////////////////
+// MD4-based checksum utility functions
+//
+// Copyright (C) 2000 Jeff Teunissen <d2deek@pmail.net>
+//
+// Author: Jeff Teunissen <d2deek@pmail.net>
+// Date: 01 Jan 2000
+
+unsigned Com_BlockChecksum (void *buffer, int length)
+{
+ int digest[4];
+ unsigned val;
+
+ mdfour ( (unsigned char *) digest, (unsigned char *) buffer, length );
+
+ val = digest[0] ^ digest[1] ^ digest[2] ^ digest[3];
+
+ return val;
+}
+
+void Com_BlockFullChecksum (void *buffer, int len, unsigned char *outbuf)
+{
+ mdfour ( outbuf, (unsigned char *) buffer, len );
+}
+