Implementation of Shamir's trick (working in progress).

[crypto_lab3.git] / src / RsaCrtShamirsTrick.h

diff --git a/src/RsaCrtShamirsTrick.h b/src/RsaCrtShamirsTrick.h
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+++ b/src/RsaCrtShamirsTrick.h
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+#ifndef RSACRT_SHAMIRS_TRICK_H
+#define RSACRT_SHAMIRS_TRICK_H
+
+#include <utility>
+#include <exception>
+
+#include <gmpxx.h>
+
+#include "Rsa.h"
+
+class RsaCrtShamirsTrick
+{
+public:
+   class UnableToSignWithShamirsTrick : public std::exception {};
+
+   struct KeyPriv {
+      mpz_class p;
+      mpz_class q;
+      mpz_class d;
+      mpz_class qInv;
+   };
+
+   /**
+    * Generate a pair of keys (public, private).
+    */
+   static std::pair<Rsa::KeyPub, KeyPriv> generateRSAKeys(uint exponent, uint keySizeBits);
+
+   /**
+    * m must not be greater or equal than kPriv.n.
+    * Use the Shamir's trick to test if a fault has been created during the computation of Sp and Sq.
+    * If so it throws 'UnableToSignWithShamirsTrick'.
+    * @param m the message to sign. No padding is used.
+    */
+   static mpz_class sign(const mpz_class& m, const KeyPriv& kPriv);
+
+   /**
+    * Sp is altered by flipping its 42nd bit.
+    * @param m the message to sign. No padding is used.
+    */
+   static mpz_class signWithFaultySp(const mpz_class& m, const KeyPriv& kPriv);
+};
+
+#endif