PFC::PFC(int s)
{
int t,u,v,b,words,mod_bits;
if (s!=80 && s!=128)
{
cout << "No suitable curve available" << endl;
exit(0);
}
if (s==80) mod_bits=379;
if (s==128) mod_bits=1223;
words=(mod_bits/MIRACL)+1;
#ifdef MR_SIMPLE_BASE
miracl *mip=mirsys((MIRACL/4)*words,16);
#else
miracl *mip=mirsys(words,0);
mip->IOBASE=16;
#endif
ord=new Big;
S=s;
M=mod_bits;
if (s==80)
{
t=253; u=251; v=59; B=1; CF=1;
*ord=pow((Big)2,M)+pow((Big)2,(M+1)/2)+1; //TYPE=1
}
if (s==128)
{
t=255; u=0; v=0; B=0; CF=5;
*ord=pow((Big)2,M)+pow((Big)2,(M+1)/2)+1; //TYPE=1
}
*ord/=CF;
#ifdef MR_AFFINE_ONLY
ecurve2(-M,t,u,v,(Big)1,(Big)B,TRUE,MR_AFFINE);
#else
ecurve2(-M,t,u,v,(Big)1,(Big)B,TRUE,MR_PROJECTIVE);
#endif
}
int main()
{
ifstream common("common2.ecs"); /* construct file I/O streams */
ifstream private_key("private.ecs");
ifstream message;
ofstream signature;
char ifname[13],ofname[13];
EC2 G;
Big a2,a6,q,x,y,h,r,s,d,k;
long seed;
int m,a,b,c,cf;
miracl *mip=&precision;
/* randomise */
cout << "Enter 9 digit random number seed = ";
cin >> seed;
irand(seed);
/* get common data */
common >> m;
mip->IOBASE=16;
common >> a2 >> a6 >> q >> x >> y;
mip->IOBASE=10;
common >> a >> b >> c;
/* calculate r - this can be done off-line,
and hence amortized to almost nothing */
ecurve2(m,a,b,c,a2,a6,FALSE,MR_PROJECTIVE);
G=EC2(x,y);
k=rand(q);
G*=k; /* see brick.cpp for technique to speed this up */
G.get(r);
r%=q;
/* get private key of recipient */
private_key >> d;
/* get message */
cout << "file to be signed = " ;
cin >> ifname;
strcpy(ofname,ifname);
strip(ofname);
strcat(ofname,".ecs");
message.open(ifname,ios::binary|ios::in|ios::nocreate);
if (!message)
{
cout << "Unable to open file " << ifname << "\n";
return 0;
}
h=hash(message);
/* calculate s */
k=inverse(k,q);
s=((h+d*r)*k)%q;
signature.open(ofname);
mip->IOBASE=10;
signature << r << endl;
signature << s << endl;
return 0;
}