int DecodeShortV3(const char* serial, bool level10, unsigned char* dest, int dest_len)
{
char keybytes_[512];
char* kb=keybytes_;
char* keybytes=keybytes_;
char* k1;
char* k2;
bool keystring=false;
int keylength;
const char* udigits="0123456789ABCDEFGHJKMNPQRTUVWXYZ";
const char* ldigits="0123456789abcdefghjkmnpqrtuvwxyz";
const char* c=serial;
const char* p;
unsigned char value=0;
unsigned char firstdigit=1;
BigInt n, n2, n3;
n=BigInt_Create();
n2=BigInt_Create();
n3=BigInt_Create();
int level=0;
if(level10)
level=10;
if(serial==0 || serial[0]==0)
{
return 0;
}
while(c[0])
{
p=strchr(udigits, c[0]); //first the current serial character in udigits
if(p)
{
value=p-udigits;
}
else
{
p=strchr(ldigits, c[0]); //first the current character in ldigits
if(p)
{
value=p-ldigits;
}
else if(c[0]=='i' || c[0]=='I' || c[0]=='l' || c[0]=='L')
{
value=1;
}
else if(c[0]=='o' || c[0]=='O')
{
value=0;
}
else if(c[0]=='s' || c[0]=='S')
{
value=5;
}
else
{
value=32;
}
}
c++;
if(value<32) //must be base32
{
if(firstdigit) //ignore the first key character
{
if(level==10)
{
/* All level 10 keys start with the digit 1. It
doesn't convey any information other than the fact
that they're level 10 keys; discard it. */
//KeyString starts with 3
if(value==3)
{
value=0;
keystring=true; //TODO: remove?
}
if(value!=0)
{
value=0;
firstdigit=0;
}
}
else
{
//KeyString starts with 3
if(value==3)
{
value=0;
keystring=true; //TODO: remove?
}
if(value!=0 && value>=16)
{
value-=16;
firstdigit=0;
}
}
}
BigInt_Shift(n, 5, n2);
BigInt_SetU(n3, value);
BigInt_Add(n2, n3, n);
}
} //end of loop
//Spit out the bytes, in reverse order.
BigInt_Set(n3, 0xFF);
if(level==10)
{
while(BigInt_Compare(n, BigInt_One())>0)
{
BigInt_And(n, n3, n2);
kb[0]=(unsigned char)BigInt_GetU(n2);
kb++;
BigInt_Shift(n, -8, n2);
BigInt_Copy(n, n2);
}
}
else
{
while(BigInt_Compare(n, BigInt_Zero())!=0)
{
BigInt_And(n, n3, n2);
kb[0]=(unsigned char)BigInt_GetU(n2);
kb++;
BigInt_Shift(n, -8, n2);
BigInt_Copy(n, n2);
}
}
if((kb-keybytes)%2) //if the length / 2 has a remainder
{
kb[0]=0; //discard last byte?
kb++;
}
/* Reverse digits in keybytes */
k1=keybytes;
k2=kb-1;
while(k1<k2)
{
char t=k1[0];
k1[0]=k2[0];
k2[0]=t;
k2--;
k1++;
}
BigInt_Destroy(n3);
BigInt_Destroy(n2);
BigInt_Destroy(n);
keylength=kb-keybytes;
memset(dest, 0, dest_len);
memcpy(dest, keybytes, keylength);
return keylength;
}
int BigInt_Divide(BigInt a, BigInt b, BigInt answer, BigInt remainder)
{
//TODO: fix something here (memleak temp1 or t)
int compare, i, signa, signb;
WORKING_DIGIT high, low, t;
BigInt temp1, temp2;
temp1=BigInt_Create();
temp2=BigInt_Create();
signa=a->negative;
a->negative=0;
signb=b->negative;
b->negative=0;
/* Check for divide-by-zero, it's not allowed */
if(b->length==1 && b->digits[0]==0) return 0;
/* Compare a and b, to see if we can take a shortcut */
compare=BigInt_Compare_SignOptional(a, b, 1);
if(compare<0)
{
BigInt_Set(answer, 0);
BigInt_Copy(remainder, a);
return 1;
}
else if(compare==0)
{
BigInt_Set(answer, 1);
BigInt_Set(remainder, 0);
return 1;
}
BigInt_Realloc(answer, a->length, 0);
BigInt_Set(remainder, 0);
for(i=1; i<=a->length; ++i)
{
/* remainder=(remainder<<BITS_PER_DIGIT)+a->digits[a->length-i]; */
BigInt_Copy(temp1, remainder);
BigInt_Shift(temp1, BITS_PER_DIGIT, remainder);
remainder->digits[0]=a->digits[a->length-i];
if(BigInt_Compare_SignOptional(remainder, b, 1)>=0)
{
high=OVERFLOW_DIGIT;
low=0;
while(low<high)
{
t=((high-low)/2)+low;
/* if ((b*t)>remainder) high=t; else low=t+1; */
BigInt_Set(temp2, t);
BigInt_Multiply(b, temp2, temp1);
if(BigInt_Compare(temp1, remainder)>0) high=t;
else low=t+1;
}
t=low-1;
answer->digits[a->length-i]=(DIGIT)(t);
/* remainder=remainder-(b*t) */
BigInt_Set(temp2, t);
BigInt_Multiply(b, temp2, temp1);
BigInt_Subtract(remainder, temp1, temp2);
BigInt_Copy(remainder, temp2);
}
else answer->digits[a->length-i]=0;
}
a->negative=signa;
b->negative=signb;
answer->negative=(a->negative ^ b->negative);
BigInt_FindMSD(answer);
BigInt_Destroy(temp2);
BigInt_Destroy(temp1);
return 1;
}
char* EncodeShortV3(unsigned char* keybytes, int keylength, bool level10)
{
char* cc;
char* shortv3digits=(char*)"0123456789ABCDEFGHJKMNPQRTUVWXYZ";
static char retval[512]="";
int level=0;
int dcount;
int nn;
if(level10)
level=29;
strcpy(retval, "");
BigInt n=BigInt_Create();
BigInt t1=BigInt_Create();
BigInt t2=BigInt_Create();
if(level==29)
BigInt_Set(n, 1);
for(int x=0; x<keylength; ++x)
{
BigInt_Shift(n, 8, t1);
BigInt_SetU(t2, keybytes[x]);
BigInt_Add(t1, t2, n);
}
cc=retval;
dcount=6;
while(BigInt_Compare(n, BigInt_Zero())!=0)
{
BigInt_SetU(t2, 32);
BigInt_Modulus(n, t2, t1);
nn=BigInt_Get(t1);
BigInt_Shift(n, -5, t2);
BigInt_Copy(n, t2);
if(level==29)
{
*cc++=shortv3digits[nn];
if(--dcount==0)
{
dcount=6;
*cc++='-';
}
}
else
{
if(BigInt_Compare(n, BigInt_Zero())==0)
{
if(nn<16)
{
*cc++=shortv3digits[nn+16];
--dcount;
}
else
{
*cc++=shortv3digits[nn];
if(--dcount==0)
{
dcount=6;
*cc++='-';
}
*cc++=shortv3digits[16];
--dcount;
}
}
else
{
*cc++=shortv3digits[nn];
if(--dcount==0)
{
dcount=6;
*cc++='-';
}
}
}
}
if(level==29)
{
*cc++='1';
--dcount;
}
while(dcount-->0)
*cc++='0';
*cc=0;
mystrrev(retval);
BigInt_Destroy(t2);
BigInt_Destroy(t1);
BigInt_Destroy(n);
return retval;
}