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+#ifndef CRYPTOPP_INTEGER_H
+#define CRYPTOPP_INTEGER_H
+
+/** \file */
+
+#include "cryptlib.h"
+#include "secblock.h"
+
+#include <iosfwd>
+#include <algorithm>
+
+NAMESPACE_BEGIN(CryptoPP)
+
+struct InitializeInteger // used to initialize static variables
+{
+ InitializeInteger();
+};
+
+typedef SecBlock<word, AllocatorWithCleanup<word, CRYPTOPP_BOOL_X86> > IntegerSecBlock;
+
+//! multiple precision integer and basic arithmetics
+/*! This class can represent positive and negative integers
+ with absolute value less than (256**sizeof(word)) ** (256**sizeof(int)).
+ \nosubgrouping
+*/
+class CRYPTOPP_DLL Integer : private InitializeInteger, public ASN1Object
+{
+public:
+ //! \name ENUMS, EXCEPTIONS, and TYPEDEFS
+ //@{
+ //! division by zero exception
+ class DivideByZero : public Exception
+ {
+ public:
+ DivideByZero() : Exception(OTHER_ERROR, "Integer: division by zero") {}
+ };
+
+ //!
+ class RandomNumberNotFound : public Exception
+ {
+ public:
+ RandomNumberNotFound() : Exception(OTHER_ERROR, "Integer: no integer satisfies the given parameters") {}
+ };
+
+ //!
+ enum Sign {POSITIVE=0, NEGATIVE=1};
+
+ //!
+ enum Signedness {
+ //!
+ UNSIGNED,
+ //!
+ SIGNED};
+
+ //!
+ enum RandomNumberType {
+ //!
+ ANY,
+ //!
+ PRIME};
+ //@}
+
+ //! \name CREATORS
+ //@{
+ //! creates the zero integer
+ Integer();
+
+ //! copy constructor
+ Integer(const Integer& t);
+
+ //! convert from signed long
+ Integer(signed long value);
+
+ //! convert from lword
+ Integer(Sign s, lword value);
+
+ //! convert from two words
+ Integer(Sign s, word highWord, word lowWord);
+
+ //! convert from string
+ /*! str can be in base 2, 8, 10, or 16. Base is determined by a
+ case insensitive suffix of 'h', 'o', or 'b'. No suffix means base 10.
+ */
+ explicit Integer(const char *str);
+ explicit Integer(const wchar_t *str);
+
+ //! convert from big-endian byte array
+ Integer(const byte *encodedInteger, size_t byteCount, Signedness s=UNSIGNED);
+
+ //! convert from big-endian form stored in a BufferedTransformation
+ Integer(BufferedTransformation &bt, size_t byteCount, Signedness s=UNSIGNED);
+
+ //! convert from BER encoded byte array stored in a BufferedTransformation object
+ explicit Integer(BufferedTransformation &bt);
+
+ //! create a random integer
+ /*! The random integer created is uniformly distributed over [0, 2**bitcount). */
+ Integer(RandomNumberGenerator &rng, size_t bitcount);
+
+ //! avoid calling constructors for these frequently used integers
+ static const Integer & CRYPTOPP_API Zero();
+ //! avoid calling constructors for these frequently used integers
+ static const Integer & CRYPTOPP_API One();
+ //! avoid calling constructors for these frequently used integers
+ static const Integer & CRYPTOPP_API Two();
+
+ //! create a random integer of special type
+ /*! Ideally, the random integer created should be uniformly distributed
+ over {x | min <= x <= max and x is of rnType and x % mod == equiv}.
+ However the actual distribution may not be uniform because sequential
+ search is used to find an appropriate number from a random starting
+ point.
+ May return (with very small probability) a pseudoprime when a prime
+ is requested and max > lastSmallPrime*lastSmallPrime (lastSmallPrime
+ is declared in nbtheory.h).
+ \throw RandomNumberNotFound if the set is empty.
+ */
+ Integer(RandomNumberGenerator &rng, const Integer &min, const Integer &max, RandomNumberType rnType=ANY, const Integer &equiv=Zero(), const Integer &mod=One());
+
+ //! return the integer 2**e
+ static Integer CRYPTOPP_API Power2(size_t e);
+ //@}
+
+ //! \name ENCODE/DECODE
+ //@{
+ //! minimum number of bytes to encode this integer
+ /*! MinEncodedSize of 0 is 1 */
+ size_t MinEncodedSize(Signedness=UNSIGNED) const;
+ //! encode in big-endian format
+ /*! unsigned means encode absolute value, signed means encode two's complement if negative.
+ if outputLen < MinEncodedSize, the most significant bytes will be dropped
+ if outputLen > MinEncodedSize, the most significant bytes will be padded
+ */
+ void Encode(byte *output, size_t outputLen, Signedness=UNSIGNED) const;
+ //!
+ void Encode(BufferedTransformation &bt, size_t outputLen, Signedness=UNSIGNED) const;
+
+ //! encode using Distinguished Encoding Rules, put result into a BufferedTransformation object
+ void DEREncode(BufferedTransformation &bt) const;
+
+ //! encode absolute value as big-endian octet string
+ void DEREncodeAsOctetString(BufferedTransformation &bt, size_t length) const;
+
+ //! encode absolute value in OpenPGP format, return length of output
+ size_t OpenPGPEncode(byte *output, size_t bufferSize) const;
+ //! encode absolute value in OpenPGP format, put result into a BufferedTransformation object
+ size_t OpenPGPEncode(BufferedTransformation &bt) const;
+
+ //!
+ void Decode(const byte *input, size_t inputLen, Signedness=UNSIGNED);
+ //!
+ //* Precondition: bt.MaxRetrievable() >= inputLen
+ void Decode(BufferedTransformation &bt, size_t inputLen, Signedness=UNSIGNED);
+
+ //!
+ void BERDecode(const byte *input, size_t inputLen);
+ //!
+ void BERDecode(BufferedTransformation &bt);
+
+ //! decode nonnegative value as big-endian octet string
+ void BERDecodeAsOctetString(BufferedTransformation &bt, size_t length);
+
+ class OpenPGPDecodeErr : public Exception
+ {
+ public:
+ OpenPGPDecodeErr() : Exception(INVALID_DATA_FORMAT, "OpenPGP decode error") {}
+ };
+
+ //!
+ void OpenPGPDecode(const byte *input, size_t inputLen);
+ //!
+ void OpenPGPDecode(BufferedTransformation &bt);
+ //@}
+
+ //! \name ACCESSORS
+ //@{
+ //! return true if *this can be represented as a signed long
+ bool IsConvertableToLong() const;
+ //! return equivalent signed long if possible, otherwise undefined
+ signed long ConvertToLong() const;
+
+ //! number of significant bits = floor(log2(abs(*this))) + 1
+ unsigned int BitCount() const;
+ //! number of significant bytes = ceiling(BitCount()/8)
+ unsigned int ByteCount() const;
+ //! number of significant words = ceiling(ByteCount()/sizeof(word))
+ unsigned int WordCount() const;
+
+ //! return the i-th bit, i=0 being the least significant bit
+ bool GetBit(size_t i) const;
+ //! return the i-th byte
+ byte GetByte(size_t i) const;
+ //! return n lowest bits of *this >> i
+ lword GetBits(size_t i, size_t n) const;
+
+ //!
+ bool IsZero() const {return !*this;}
+ //!
+ bool NotZero() const {return !IsZero();}
+ //!
+ bool IsNegative() const {return sign == NEGATIVE;}
+ //!
+ bool NotNegative() const {return !IsNegative();}
+ //!
+ bool IsPositive() const {return NotNegative() && NotZero();}
+ //!
+ bool NotPositive() const {return !IsPositive();}
+ //!
+ bool IsEven() const {return GetBit(0) == 0;}
+ //!
+ bool IsOdd() const {return GetBit(0) == 1;}
+ //@}
+
+ //! \name MANIPULATORS
+ //@{
+ //!
+ Integer& operator=(const Integer& t);
+
+ //!
+ Integer& operator+=(const Integer& t);
+ //!
+ Integer& operator-=(const Integer& t);
+ //!
+ Integer& operator*=(const Integer& t) {return *this = Times(t);}
+ //!
+ Integer& operator/=(const Integer& t) {return *this = DividedBy(t);}
+ //!
+ Integer& operator%=(const Integer& t) {return *this = Modulo(t);}
+ //!
+ Integer& operator/=(word t) {return *this = DividedBy(t);}
+ //!
+ Integer& operator%=(word t) {return *this = Integer(POSITIVE, 0, Modulo(t));}
+
+ //!
+ Integer& operator<<=(size_t);
+ //!
+ Integer& operator>>=(size_t);
+
+ //!
+ void Randomize(RandomNumberGenerator &rng, size_t bitcount);
+ //!
+ void Randomize(RandomNumberGenerator &rng, const Integer &min, const Integer &max);
+ //! set this Integer to a random element of {x | min <= x <= max and x is of rnType and x % mod == equiv}
+ /*! returns false if the set is empty */
+ bool Randomize(RandomNumberGenerator &rng, const Integer &min, const Integer &max, RandomNumberType rnType, const Integer &equiv=Zero(), const Integer &mod=One());
+
+ bool GenerateRandomNoThrow(RandomNumberGenerator &rng, const NameValuePairs &params = g_nullNameValuePairs);
+ void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &params = g_nullNameValuePairs)
+ {
+ if (!GenerateRandomNoThrow(rng, params))
+ throw RandomNumberNotFound();
+ }
+
+ //! set the n-th bit to value
+ void SetBit(size_t n, bool value=1);
+ //! set the n-th byte to value
+ void SetByte(size_t n, byte value);
+
+ //!
+ void Negate();
+ //!
+ void SetPositive() {sign = POSITIVE;}
+ //!
+ void SetNegative() {if (!!(*this)) sign = NEGATIVE;}
+
+ //!
+ void swap(Integer &a);
+ //@}
+
+ //! \name UNARY OPERATORS
+ //@{
+ //!
+ bool operator!() const;
+ //!
+ Integer operator+() const {return *this;}
+ //!
+ Integer operator-() const;
+ //!
+ Integer& operator++();
+ //!
+ Integer& operator--();
+ //!
+ Integer operator++(int) {Integer temp = *this; ++*this; return temp;}
+ //!
+ Integer operator--(int) {Integer temp = *this; --*this; return temp;}
+ //@}
+
+ //! \name BINARY OPERATORS
+ //@{
+ //! signed comparison
+ /*! \retval -1 if *this < a
+ \retval 0 if *this = a
+ \retval 1 if *this > a
+ */
+ int Compare(const Integer& a) const;
+
+ //!
+ Integer Plus(const Integer &b) const;
+ //!
+ Integer Minus(const Integer &b) const;
+ //!
+ Integer Times(const Integer &b) const;
+ //!
+ Integer DividedBy(const Integer &b) const;
+ //!
+ Integer Modulo(const Integer &b) const;
+ //!
+ Integer DividedBy(word b) const;
+ //!
+ word Modulo(word b) const;
+
+ //!
+ Integer operator>>(size_t n) const {return Integer(*this)>>=n;}
+ //!
+ Integer operator<<(size_t n) const {return Integer(*this)<<=n;}
+ //@}
+
+ //! \name OTHER ARITHMETIC FUNCTIONS
+ //@{
+ //!
+ Integer AbsoluteValue() const;
+ //!
+ Integer Doubled() const {return Plus(*this);}
+ //!
+ Integer Squared() const {return Times(*this);}
+ //! extract square root, if negative return 0, else return floor of square root
+ Integer SquareRoot() const;
+ //! return whether this integer is a perfect square
+ bool IsSquare() const;
+
+ //! is 1 or -1
+ bool IsUnit() const;
+ //! return inverse if 1 or -1, otherwise return 0
+ Integer MultiplicativeInverse() const;
+
+ //! modular multiplication
+ CRYPTOPP_DLL friend Integer CRYPTOPP_API a_times_b_mod_c(const Integer &x, const Integer& y, const Integer& m);
+ //! modular exponentiation
+ CRYPTOPP_DLL friend Integer CRYPTOPP_API a_exp_b_mod_c(const Integer &x, const Integer& e, const Integer& m);
+
+ //! calculate r and q such that (a == d*q + r) && (0 <= r < abs(d))
+ static void CRYPTOPP_API Divide(Integer &r, Integer &q, const Integer &a, const Integer &d);
+ //! use a faster division algorithm when divisor is short
+ static void CRYPTOPP_API Divide(word &r, Integer &q, const Integer &a, word d);
+
+ //! returns same result as Divide(r, q, a, Power2(n)), but faster
+ static void CRYPTOPP_API DivideByPowerOf2(Integer &r, Integer &q, const Integer &a, unsigned int n);
+
+ //! greatest common divisor
+ static Integer CRYPTOPP_API Gcd(const Integer &a, const Integer &n);
+ //! calculate multiplicative inverse of *this mod n
+ Integer InverseMod(const Integer &n) const;
+ //!
+ word InverseMod(word n) const;
+ //@}
+
+ //! \name INPUT/OUTPUT
+ //@{
+ //!
+ friend CRYPTOPP_DLL std::istream& CRYPTOPP_API operator>>(std::istream& in, Integer &a);
+ //!
+ friend CRYPTOPP_DLL std::ostream& CRYPTOPP_API operator<<(std::ostream& out, const Integer &a);
+ //@}
+
+private:
+ friend class ModularArithmetic;
+ friend class MontgomeryRepresentation;
+ friend class HalfMontgomeryRepresentation;
+
+ Integer(word value, size_t length);
+
+ int PositiveCompare(const Integer &t) const;
+ friend void PositiveAdd(Integer &sum, const Integer &a, const Integer &b);
+ friend void PositiveSubtract(Integer &diff, const Integer &a, const Integer &b);
+ friend void PositiveMultiply(Integer &product, const Integer &a, const Integer &b);
+ friend void PositiveDivide(Integer &remainder, Integer &quotient, const Integer &dividend, const Integer &divisor);
+
+ IntegerSecBlock reg;
+ Sign sign;
+};
+
+//!
+inline bool operator==(const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)==0;}
+//!
+inline bool operator!=(const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)!=0;}
+//!
+inline bool operator> (const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)> 0;}
+//!
+inline bool operator>=(const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)>=0;}
+//!
+inline bool operator< (const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)< 0;}
+//!
+inline bool operator<=(const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)<=0;}
+//!
+inline CryptoPP::Integer operator+(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.Plus(b);}
+//!
+inline CryptoPP::Integer operator-(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.Minus(b);}
+//!
+inline CryptoPP::Integer operator*(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.Times(b);}
+//!
+inline CryptoPP::Integer operator/(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.DividedBy(b);}
+//!
+inline CryptoPP::Integer operator%(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.Modulo(b);}
+//!
+inline CryptoPP::Integer operator/(const CryptoPP::Integer &a, CryptoPP::word b) {return a.DividedBy(b);}
+//!
+inline CryptoPP::word operator%(const CryptoPP::Integer &a, CryptoPP::word b) {return a.Modulo(b);}
+
+NAMESPACE_END
+
+#ifndef __BORLANDC__
+NAMESPACE_BEGIN(std)
+inline void swap(CryptoPP::Integer &a, CryptoPP::Integer &b)
+{
+ a.swap(b);
+}
+NAMESPACE_END
+#endif
+
+#endif