summaryrefslogtreecommitdiff
path: root/src-cryptopp/ec2n.h
diff options
context:
space:
mode:
authorMicah Anderson <micah@riseup.net>2013-08-22 16:39:52 -0400
committerMicah Anderson <micah@riseup.net>2013-08-22 16:39:52 -0400
commit5e60e0e3af85f22aa0afe8bf0ecf85619afacfeb (patch)
tree6a91a3de86fa8de0b4167cc947ab72991bf8da31 /src-cryptopp/ec2n.h
parent30e9097985656920f01a72efc1088caa2b8d41b3 (diff)
Imported Upstream version 0.6.0.12upstream/0.6.0.12
Diffstat (limited to 'src-cryptopp/ec2n.h')
-rw-r--r--src-cryptopp/ec2n.h113
1 files changed, 113 insertions, 0 deletions
diff --git a/src-cryptopp/ec2n.h b/src-cryptopp/ec2n.h
new file mode 100644
index 0000000..ae4007c
--- /dev/null
+++ b/src-cryptopp/ec2n.h
@@ -0,0 +1,113 @@
+#ifndef CRYPTOPP_EC2N_H
+#define CRYPTOPP_EC2N_H
+
+#include "gf2n.h"
+#include "eprecomp.h"
+#include "smartptr.h"
+#include "pubkey.h"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+//! Elliptic Curve Point
+struct CRYPTOPP_DLL EC2NPoint
+{
+ EC2NPoint() : identity(true) {}
+ EC2NPoint(const PolynomialMod2 &x, const PolynomialMod2 &y)
+ : identity(false), x(x), y(y) {}
+
+ bool operator==(const EC2NPoint &t) const
+ {return (identity && t.identity) || (!identity && !t.identity && x==t.x && y==t.y);}
+ bool operator< (const EC2NPoint &t) const
+ {return identity ? !t.identity : (!t.identity && (x<t.x || (x==t.x && y<t.y)));}
+
+ bool identity;
+ PolynomialMod2 x, y;
+};
+
+CRYPTOPP_DLL_TEMPLATE_CLASS AbstractGroup<EC2NPoint>;
+
+//! Elliptic Curve over GF(2^n)
+class CRYPTOPP_DLL EC2N : public AbstractGroup<EC2NPoint>
+{
+public:
+ typedef GF2NP Field;
+ typedef Field::Element FieldElement;
+ typedef EC2NPoint Point;
+
+ EC2N() {}
+ EC2N(const Field &field, const Field::Element &a, const Field::Element &b)
+ : m_field(field), m_a(a), m_b(b) {}
+ // construct from BER encoded parameters
+ // this constructor will decode and extract the the fields fieldID and curve of the sequence ECParameters
+ EC2N(BufferedTransformation &bt);
+
+ // encode the fields fieldID and curve of the sequence ECParameters
+ void DEREncode(BufferedTransformation &bt) const;
+
+ bool Equal(const Point &P, const Point &Q) const;
+ const Point& Identity() const;
+ const Point& Inverse(const Point &P) const;
+ bool InversionIsFast() const {return true;}
+ const Point& Add(const Point &P, const Point &Q) const;
+ const Point& Double(const Point &P) const;
+
+ Point Multiply(const Integer &k, const Point &P) const
+ {return ScalarMultiply(P, k);}
+ Point CascadeMultiply(const Integer &k1, const Point &P, const Integer &k2, const Point &Q) const
+ {return CascadeScalarMultiply(P, k1, Q, k2);}
+
+ bool ValidateParameters(RandomNumberGenerator &rng, unsigned int level=3) const;
+ bool VerifyPoint(const Point &P) const;
+
+ unsigned int EncodedPointSize(bool compressed = false) const
+ {return 1 + (compressed?1:2)*m_field->MaxElementByteLength();}
+ // returns false if point is compressed and not valid (doesn't check if uncompressed)
+ bool DecodePoint(Point &P, BufferedTransformation &bt, size_t len) const;
+ bool DecodePoint(Point &P, const byte *encodedPoint, size_t len) const;
+ void EncodePoint(byte *encodedPoint, const Point &P, bool compressed) const;
+ void EncodePoint(BufferedTransformation &bt, const Point &P, bool compressed) const;
+
+ Point BERDecodePoint(BufferedTransformation &bt) const;
+ void DEREncodePoint(BufferedTransformation &bt, const Point &P, bool compressed) const;
+
+ Integer FieldSize() const {return Integer::Power2(m_field->MaxElementBitLength());}
+ const Field & GetField() const {return *m_field;}
+ const FieldElement & GetA() const {return m_a;}
+ const FieldElement & GetB() const {return m_b;}
+
+ bool operator==(const EC2N &rhs) const
+ {return GetField() == rhs.GetField() && m_a == rhs.m_a && m_b == rhs.m_b;}
+
+private:
+ clonable_ptr<Field> m_field;
+ FieldElement m_a, m_b;
+ mutable Point m_R;
+};
+
+CRYPTOPP_DLL_TEMPLATE_CLASS DL_FixedBasePrecomputationImpl<EC2N::Point>;
+CRYPTOPP_DLL_TEMPLATE_CLASS DL_GroupPrecomputation<EC2N::Point>;
+
+template <class T> class EcPrecomputation;
+
+//! EC2N precomputation
+template<> class EcPrecomputation<EC2N> : public DL_GroupPrecomputation<EC2N::Point>
+{
+public:
+ typedef EC2N EllipticCurve;
+
+ // DL_GroupPrecomputation
+ const AbstractGroup<Element> & GetGroup() const {return m_ec;}
+ Element BERDecodeElement(BufferedTransformation &bt) const {return m_ec.BERDecodePoint(bt);}
+ void DEREncodeElement(BufferedTransformation &bt, const Element &v) const {m_ec.DEREncodePoint(bt, v, false);}
+
+ // non-inherited
+ void SetCurve(const EC2N &ec) {m_ec = ec;}
+ const EC2N & GetCurve() const {return m_ec;}
+
+private:
+ EC2N m_ec;
+};
+
+NAMESPACE_END
+
+#endif