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mdfour.c

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/* 
   Unix SMB/Netbios implementation.
   Version 1.9.
   a implementation of MD4 designed for use in the SMB authentication protocol
   Copyright (C) Andrew Tridgell 1997-1998.
   
   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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "rsync.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 MASK32 (0xffffffff)

#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))&MASK32) | (((x)>>(32-(s)))&MASK32)))

#define ROUND1(a,b,c,d,k,s) a = lshift((a + F(b,c,d) + M[k])&MASK32, s)
#define ROUND2(a,b,c,d,k,s) a = lshift((a + G(b,c,d) + M[k] + 0x5A827999)&MASK32,s)
#define ROUND3(a,b,c,d,k,s) a = lshift((a + H(b,c,d) + M[k] + 0x6ED9EBA1)&MASK32,s)

/* this applies md4 to 64 byte chunks */
static void mdfour64(uint32 *M)
{
        uint32 AA, BB, CC, DD;
        uint32 A,B,C,D;

        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;
        
        A &= MASK32; B &= MASK32; 
        C &= MASK32; D &= MASK32;

        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];

        if (n == 0) mdfour_tail(in, n);

        m = md;

        while (n >= 64) {
                copy64(M, in);
                mdfour64(M);
                in += 64;
                n -= 64;
                m->totalN += 64;
        }

        if (n) 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);
}

#ifdef TEST_MDFOUR
static void file_checksum1(char *fname)
{
        int fd, i;
        struct mdfour md;
        unsigned char buf[64*1024], sum[16];
        
        fd = open(fname,O_RDONLY);
        if (fd == -1) {
                perror("fname");
                exit(1);
        }
        
        mdfour_begin(&md);

        while (1) {
                int n = read(fd, buf, sizeof(buf));
                if (n <= 0) break;
                mdfour_update(&md, buf, n);
        }

        close(fd);

        mdfour_result(&md, sum);

        for (i=0;i<16;i++)
                printf("%02X", sum[i]);
        printf("\n");
}

#if 0
#include "../md4.h"

static void file_checksum2(char *fname)
{
        int fd, i;
        MDstruct md;
        unsigned char buf[64], sum[16];

        fd = open(fname,O_RDONLY);
        if (fd == -1) {
                perror("fname");
                exit(1);
        }
        
        MDbegin(&md);

        while (1) {
                int n = read(fd, buf, sizeof(buf));
                if (n <= 0) break;
                MDupdate(&md, buf, n*8);
        }

        if (!md.done) {
                MDupdate(&md, buf, 0);
        }

        close(fd);

        memcpy(sum, md.buffer, 16);

        for (i=0;i<16;i++)
                printf("%02X", sum[i]);
        printf("\n");
}
#endif

 int main(int argc, char *argv[])
{
        file_checksum1(argv[1]);
#if 0
        file_checksum2(argv[1]);
#endif
        return 0;
}
#endif

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