RosettaCodeData/Task/MD4/C/md4-1.c

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/*
*
* Author: George Mossessian
*
* The MD4 hash algorithm, as described in https://tools.ietf.org/html/rfc1320
*/
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
char *MD4(char *str, int len); //this is the prototype you want to call. Everything else is internal.
typedef struct string{
char *c;
int len;
char sign;
}string;
static uint32_t *MD4Digest(uint32_t *w, int len);
static void setMD4Registers(uint32_t AA, uint32_t BB, uint32_t CC, uint32_t DD);
static uint32_t changeEndianness(uint32_t x);
static void resetMD4Registers(void);
static string stringCat(string first, string second);
static string uint32ToString(uint32_t l);
static uint32_t stringToUint32(string s);
static const char *BASE16 = "0123456789abcdef=";
#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 LEFTROTATE(A,N) ((A)<<(N))|((A)>>(32-(N)))
#define MD4ROUND1(a,b,c,d,x,s) a += F(b,c,d) + x; a = LEFTROTATE(a, s);
#define MD4ROUND2(a,b,c,d,x,s) a += G(b,c,d) + x + (uint32_t)0x5A827999; a = LEFTROTATE(a, s);
#define MD4ROUND3(a,b,c,d,x,s) a += H(b,c,d) + x + (uint32_t)0x6ED9EBA1; a = LEFTROTATE(a, s);
static uint32_t A = 0x67452301;
static uint32_t B = 0xefcdab89;
static uint32_t C = 0x98badcfe;
static uint32_t D = 0x10325476;
string newString(char * c, int t){
string r;
int i;
if(c!=NULL){
r.len = (t<=0)?strlen(c):t;
r.c=(char *)malloc(sizeof(char)*(r.len+1));
for(i=0; i<r.len; i++) r.c[i]=c[i];
r.c[r.len]='\0';
return r;
}
r.len=t;
r.c=(char *)malloc(sizeof(char)*(r.len+1));
memset(r.c,(char)0,sizeof(char)*(t+1));
r.sign = 1;
return r;
}
string stringCat(string first, string second){
string str=newString(NULL, first.len+second.len);
int i;
for(i=0; i<first.len; i++){
str.c[i]=first.c[i];
}
for(i=first.len; i<str.len; i++){
str.c[i]=second.c[i-first.len];
}
return str;
}
string base16Encode(string in){
string out=newString(NULL, in.len*2);
int i,j;
j=0;
for(i=0; i<in.len; i++){
out.c[j++]=BASE16[((in.c[i] & 0xF0)>>4)];
out.c[j++]=BASE16[(in.c[i] & 0x0F)];
}
out.c[j]='\0';
return out;
}
string uint32ToString(uint32_t l){
string s = newString(NULL,4);
int i;
for(i=0; i<4; i++){
s.c[i] = (l >> (8*(3-i))) & 0xFF;
}
return s;
}
uint32_t stringToUint32(string s){
uint32_t l;
int i;
l=0;
for(i=0; i<4; i++){
l = l|(((uint32_t)((unsigned char)s.c[i]))<<(8*(3-i)));
}
return l;
}
char *MD4(char *str, int len){
string m=newString(str, len);
string digest;
uint32_t *w;
uint32_t *hash;
uint64_t mlen=m.len;
unsigned char oneBit = 0x80;
int i, wlen;
m=stringCat(m, newString((char *)&oneBit,1));
//append 0 ≤ k < 512 bits '0', such that the resulting message length in bits
// is congruent to 64 ≡ 448 (mod 512)4
i=((56-m.len)%64);
if(i<0) i+=64;
m=stringCat(m,newString(NULL, i));
w = malloc(sizeof(uint32_t)*(m.len/4+2));
//append length, in bits (hence <<3), least significant word first
for(i=0; i<m.len/4; i++){
w[i]=stringToUint32(newString(&(m.c[4*i]), 4));
}
w[i++] = (mlen<<3) & 0xFFFFFFFF;
w[i++] = (mlen>>29) & 0xFFFFFFFF;
wlen=i;
//change endianness, but not for the appended message length, for some reason?
for(i=0; i<wlen-2; i++){
w[i]=changeEndianness(w[i]);
}
hash = MD4Digest(w,wlen);
digest=newString(NULL,0);
for(i=0; i<4; i++){
hash[i]=changeEndianness(hash[i]);
digest=stringCat(digest,uint32ToString(hash[i]));
}
return base16Encode(digest).c;
}
uint32_t *MD4Digest(uint32_t *w, int len){
//assumes message.len is a multiple of 64 bytes.
int i,j;
uint32_t X[16];
uint32_t *digest = malloc(sizeof(uint32_t)*4);
uint32_t AA, BB, CC, DD;
for(i=0; i<len/16; i++){
for(j=0; j<16; j++){
X[j]=w[i*16+j];
}
AA=A;
BB=B;
CC=C;
DD=D;
MD4ROUND1(A,B,C,D,X[0],3);
MD4ROUND1(D,A,B,C,X[1],7);
MD4ROUND1(C,D,A,B,X[2],11);
MD4ROUND1(B,C,D,A,X[3],19);
MD4ROUND1(A,B,C,D,X[4],3);
MD4ROUND1(D,A,B,C,X[5],7);
MD4ROUND1(C,D,A,B,X[6],11);
MD4ROUND1(B,C,D,A,X[7],19);
MD4ROUND1(A,B,C,D,X[8],3);
MD4ROUND1(D,A,B,C,X[9],7);
MD4ROUND1(C,D,A,B,X[10],11);
MD4ROUND1(B,C,D,A,X[11],19);
MD4ROUND1(A,B,C,D,X[12],3);
MD4ROUND1(D,A,B,C,X[13],7);
MD4ROUND1(C,D,A,B,X[14],11);
MD4ROUND1(B,C,D,A,X[15],19);
MD4ROUND2(A,B,C,D,X[0],3);
MD4ROUND2(D,A,B,C,X[4],5);
MD4ROUND2(C,D,A,B,X[8],9);
MD4ROUND2(B,C,D,A,X[12],13);
MD4ROUND2(A,B,C,D,X[1],3);
MD4ROUND2(D,A,B,C,X[5],5);
MD4ROUND2(C,D,A,B,X[9],9);
MD4ROUND2(B,C,D,A,X[13],13);
MD4ROUND2(A,B,C,D,X[2],3);
MD4ROUND2(D,A,B,C,X[6],5);
MD4ROUND2(C,D,A,B,X[10],9);
MD4ROUND2(B,C,D,A,X[14],13);
MD4ROUND2(A,B,C,D,X[3],3);
MD4ROUND2(D,A,B,C,X[7],5);
MD4ROUND2(C,D,A,B,X[11],9);
MD4ROUND2(B,C,D,A,X[15],13);
MD4ROUND3(A,B,C,D,X[0],3);
MD4ROUND3(D,A,B,C,X[8],9);
MD4ROUND3(C,D,A,B,X[4],11);
MD4ROUND3(B,C,D,A,X[12],15);
MD4ROUND3(A,B,C,D,X[2],3);
MD4ROUND3(D,A,B,C,X[10],9);
MD4ROUND3(C,D,A,B,X[6],11);
MD4ROUND3(B,C,D,A,X[14],15);
MD4ROUND3(A,B,C,D,X[1],3);
MD4ROUND3(D,A,B,C,X[9],9);
MD4ROUND3(C,D,A,B,X[5],11);
MD4ROUND3(B,C,D,A,X[13],15);
MD4ROUND3(A,B,C,D,X[3],3);
MD4ROUND3(D,A,B,C,X[11],9);
MD4ROUND3(C,D,A,B,X[7],11);
MD4ROUND3(B,C,D,A,X[15],15);
A+=AA;
B+=BB;
C+=CC;
D+=DD;
}
digest[0]=A;
digest[1]=B;
digest[2]=C;
digest[3]=D;
resetMD4Registers();
return digest;
}
uint32_t changeEndianness(uint32_t x){
return ((x & 0xFF) << 24) | ((x & 0xFF00) << 8) | ((x & 0xFF0000) >> 8) | ((x & 0xFF000000) >> 24);
}
void setMD4Registers(uint32_t AA, uint32_t BB, uint32_t CC, uint32_t DD){
A=AA;
B=BB;
C=CC;
D=DD;
}
void resetMD4Registers(void){
setMD4Registers(0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476);
}