bignum.h

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/*
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Copyright (c) 2022, Stable Cloud Computing, Inc.
 
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
 
1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.
 
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   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.
 
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   contributors may be used to endorse or promote products derived from
   this software without specific prior written permission.
 
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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*/
#ifndef _SCC_CRYPTO_BIGNUM_H
#define _SCC_CRYPTO_BIGNUM_H
 
#include <string>
#include <ostream>
#include <memory>
 
class BignumCtx;        // forward declaration
 
namespace scc::crypto {
 
class Bignum
{
    std::unique_ptr<BignumCtx> m_bnctx;
 
public:
    Bignum();
 
    Bignum(Bignum&& other) : Bignum()
    {
        move(other);
    }
    Bignum& operator =(Bignum&& other)
    {
        move(other);
        return *this;
    }
 
    Bignum(const Bignum& other) : Bignum()
    {
        copy(other);
    }
    Bignum& operator =(const Bignum& other)
    {
        copy(other);
        return *this;
    }
 
    Bignum(uint32_t w) : Bignum()
    {
        set(w);
    }
    Bignum& operator =(uint32_t w)
    {
        set(w);
        return *this;
    }
 
    Bignum(const void * loc, int len) : Bignum()
    {
        set(loc, len);
    }
 
    virtual ~Bignum();
 
    void* bn();
    const void* const_bn() const;
 
    void set_width(int);
 
    void set(uint32_t);
    
    void set(const void *, int);
 
    void set_2sc(const void *, int);
 
    int len() const;
    
    void get(void *, int) const;
    
    int len_2sc() const;
 
    void get_2sc(void *, int) const;
    
    void copy(const Bignum&);
 
    void move(Bignum&);
 
    void clear();
 
    int width() const;
    
    void exp(const Bignum&);
    void exp(uint32_t b)
    {
        Bignum bn(b);
        exp(bn);
    }
 
    void gcd(const Bignum&);
 
    void gen_rand(int, bool = false, bool = false);
 
    bool is_prime(int = -1);
 
    void gen_prime(int);
    
    void lshift(int);
    void rshift(int);
    void add(const Bignum&);
    void add(uint32_t b)
    {
        Bignum bn(b);
        add(bn);
    }
    void sub(const Bignum&);
    void sub(uint32_t b)
    {
        Bignum bn(b);
        sub(bn);
    }
    void mul(const Bignum&);
    void mul(uint32_t b)
    {
        Bignum bn(b);
        mul(bn);
    }
    void div(const Bignum&, Bignum*);
    void div(uint32_t b, Bignum* rem)
    {
        Bignum bn(b);
        div(bn, rem);
    }
    void mod(const Bignum&);
    void mod(uint32_t b)
    {
        Bignum bn(b);
        mod(bn);
    }
    void negate();
 
    void bit_not()
    {
        for (int i = 0; i < width(); i++)
        {
            if (is_bit_set(i))
            {
                clear_bit(i);
            }
            else
            {
                set_bit(i);
            }
        }
    }
    void bit_and(const Bignum& b)
    {
        for (int i = 0; i < std::max(width(), b.width()); i++)
        {
            if (is_bit_set(i) && b.is_bit_set(i))
            {
                set_bit(i);
            }
            else
            {
                clear_bit(i);
            }
        }
    }
    void bit_or(const Bignum& b)
    {
        for (int i = 0; i < std::max(width(), b.width()); i++)
        {
            if (is_bit_set(i) || b.is_bit_set(i))
            {
                set_bit(i);
            }
            else
            {
                clear_bit(i);
            }
        }
    }
    void bit_xor(const Bignum& b)
    {
        for (int i = 0; i < std::max(width(), b.width()); i++)
        {
            if ((is_bit_set(i) && !b.is_bit_set(i)) || (!is_bit_set(i) && b.is_bit_set(i)))
            {
                set_bit(i);
            }
            else
            {
                clear_bit(i);
            }
        }
    }
 
    bool is_bit_set(int) const;
 
    void set_bit(int);
 
    void clear_bit(int);
 
    void gcd(uint32_t b)
    {
        Bignum bn(b);
        gcd(bn);
    }
 
    static bool is_prime(uint32_t w)
    {
        Bignum bn(w);
        return bn.is_prime();
    }
 
    bool is_negative() const;
 
    int cmp(uint32_t w) const;
 
    int cmp(const Bignum&) const;
 
    bool operator ==(const Bignum& o) const { return cmp(o) == 0; }
    bool operator !=(const Bignum& o) const { return cmp(o) != 0; }
    bool operator <(const Bignum& o) const { return cmp(o) < 0; }
    bool operator >(const Bignum& o) const { return cmp(o) > 0; }
    bool operator <=(const Bignum& o) const { return cmp(o) <= 0; }
    bool operator >=(const Bignum& o) const { return cmp(o) >= 0; }
    bool operator ==(uint32_t o) const { return cmp(o) == 0; }
    bool operator !=(uint32_t o) const { return cmp(o) != 0; }
    bool operator <(uint32_t o) const { return cmp(o) < 0; }
    bool operator >(uint32_t o) const { return cmp(o) > 0; }
    bool operator <=(uint32_t o) const { return cmp(o) <= 0; }
    bool operator >=(uint32_t o) const { return cmp(o) >= 0; }
 
    Bignum operator <<(int shift) const
    {
        Bignum b(*this);
        b.lshift(shift);
        return b;
    }
    Bignum& operator <<=(int shift)
    {
        lshift(shift);
        return *this;
    }
    Bignum operator >>(int shift) const
    {
        Bignum b(*this);
        b.rshift(shift);
        return b;
    }
    Bignum& operator >>=(int shift)
    {
        rshift(shift);
        return *this;
    }
    Bignum operator +(const Bignum& a) const
    {
        Bignum r(*this);
        r.add(a);
        return r;
    }
    Bignum operator +=(const Bignum& a)
    {
        add(a);
        return *this;
    }
    Bignum operator +(uint32_t a) const
    {
        Bignum r(*this);
        r.add(a);
        return r;
    }
    Bignum operator +=(uint32_t a)
    {
        add(a);
        return *this;
    }
    Bignum& operator ++()
    {
        add(1); // prefix
        return *this;
    }
    Bignum operator ++(int d)
    {
        Bignum r(*this);
        add(1); // postfix
        return r;
    }
    Bignum operator -()
    {
        negate();
        return *this;
    }
    Bignum operator -(const Bignum& a) const
    {
        Bignum r(*this);
        r.sub(a);
        return r;
    }
    Bignum operator -=(const Bignum& a)
    {
        sub(a);
        return *this;
    }
    Bignum operator -(uint32_t a) const
    {
        Bignum r(*this);
        r.sub(a);
        return r;
    }
    Bignum operator -=(uint32_t a)
    {
        sub(a);
        return *this;
    }
    Bignum& operator --()
    {
        sub(1); // prefix
        return *this;
    }
    Bignum operator --(int d)
    {
        Bignum r(*this);
        sub(1); // postfix
        return r;
    }
    Bignum operator *(const Bignum& a) const
    {
        Bignum r(*this);
        r.mul(a);
        return r;
    }
    Bignum operator *=(const Bignum& a)
    {
        mul(a);
        return *this;
    }
    Bignum operator *(uint32_t a) const
    {
        Bignum r(*this);
        r.mul(a);
        return r;
    }
    Bignum operator *=(uint32_t a)
    {
        mul(a);
        return *this;
    }
    Bignum operator /(const Bignum& a) const
    {
        Bignum r(*this);
        r.div(a, nullptr);
        return r;
    }
    Bignum operator /=(const Bignum& a)
    {
        div(a, nullptr);
        return *this;
    }
    Bignum operator /(uint32_t a) const
    {
        Bignum r(*this);
        r.div(a, nullptr);
        return r;
    }
    Bignum operator /=(uint32_t a)
    {
        div(a, nullptr);
        return *this;
    }
    Bignum operator %(const Bignum& a) const
    {
        Bignum r(*this);
        r.mod(a);
        return r;
    }
    Bignum operator %=(const Bignum& a)
    {
        mod(a);
        return *this;
    }
    Bignum operator %(uint32_t a) const
    {
        Bignum r(*this);
        r.mod(a);
        return r;
    }
    Bignum operator %=(uint32_t a)
    {
        mod(a);
        return *this;
    }
    Bignum operator &(const Bignum& a) const
    {
        Bignum r(*this);
        r.bit_and(a);
        return r;
    }
    Bignum operator &=(const Bignum& a)
    {
        bit_and(a);
        return *this;
    }
    Bignum operator &(uint32_t a) const
    {
        Bignum r(*this);
        Bignum b(a);
        r.bit_and(b);
        return r;
    }
    Bignum operator &=(uint32_t a)
    {
        Bignum b(a);
        bit_and(b);
        return *this;
    }
    Bignum operator |(const Bignum& a) const
    {
        Bignum r(*this);
        r.bit_or(a);
        return r;
    }
    Bignum operator |=(const Bignum& a)
    {
        bit_or(a);
        return *this;
    }
    Bignum operator |(uint32_t a) const
    {
        Bignum r(*this);
        Bignum b(a);
        r.bit_or(b);
        return r;
    }
    Bignum operator |=(uint32_t a)
    {
        Bignum b(a);
        bit_or(b);
        return *this;
    }
    Bignum operator ^(const Bignum& a) const
    {
        Bignum r(*this);
        r.bit_xor(a);
        return r;
    }
    Bignum operator ^=(const Bignum& a)
    {
        bit_xor(a);
        return *this;
    }
    Bignum operator ^(uint32_t a) const
    {
        Bignum r(*this);
        Bignum b(a);
        r.bit_xor(b);
        return r;
    }
    Bignum operator ^=(uint32_t a)
    {
        Bignum b(a);
        bit_xor(b);
        return *this;
    }
    Bignum operator ~() const
    {
        Bignum r(*this);
        r.bit_not();
        return r;
    }
 
    std::string str(bool=false) const;
};
 
void PrintTo(const Bignum&, std::ostream*);
 
}
 
std::ostream& operator <<(std::ostream&, const scc::crypto::Bignum&);
scc::crypto::Bignum exp(const scc::crypto::Bignum&, const scc::crypto::Bignum&);
scc::crypto::Bignum exp(const scc::crypto::Bignum&, uint32_t);
scc::crypto::Bignum gcd(const scc::crypto::Bignum&, const scc::crypto::Bignum&);
scc::crypto::Bignum gcd(const scc::crypto::Bignum&, uint32_t);
 
#endif