Fix ECP leakage in Add() and Double() (GH #869, PR #871)

This check-in provides the fix for leaks in ECP's Add() and Double(). The fixes were taken from Joost Renes, Craig Costello, and Lejla Batina's [Complete addition formulas for prime order elliptic curves](https://eprint.iacr.org/2015/1060.pdf).

The Pull Request includes two additional changes that were related to testing the primary fix. First, an `AuthenticatedKeyAgreementWithRolesValidate` interface was added. It allows us to test key agreement when roles are involved. Roles are "client", "server", "initiator", "recipient", etc.

Second, `SetGlobalSeed` was added to `test.cpp` to help with reproducible results. We had code in two different places that set the seed value for the random number generator. But it was sloppy and doing a poor job since results could not be reproduced under some circumstances.

1 files changed, 38 insertions, 8 deletions

diff --git a/validat7.cpp b/validat7.cpp
index 97f1f81b..3567b3c8 100644
--- a/validat7.cpp
+++ b/validat7.cpp
@@ -76,7 +76,7 @@ bool ValidateMQV()
 bool ValidateHMQV()

 {

 	std::cout << "\nHMQV validation suite running...\n\n";

-	bool success = true;

+	bool success = true, fail;

 

 	FileSource f256(DataDir("TestData/hmqv256.dat").c_str(), true, new HexDecoder);

 	FileSource f384(DataDir("TestData/hmqv384.dat").c_str(), true, new HexDecoder);

@@ -91,7 +91,12 @@ bool ValidateHMQV()
 	const OID oid = ASN1::secp256r1();

 	ECHMQV< ECP >::Domain hmqvA256(oid, true /*client*/);

 

-	success = AuthenticatedKeyAgreementWithRolesValidate(hmqvA256, hmqvB256) && success;

+	fail = !AuthenticatedKeyAgreementWithRolesValidate(hmqvA256, hmqvB256);

+	success = !fail && success;

+	if (fail == false)

+		std::cout << "passed    authenticated key agreement" << std::endl;

+	else

+		std::cout << "FAILED    authenticated key agreement" << std::endl;

 

 	/////////////////////////

 

@@ -102,7 +107,12 @@ bool ValidateHMQV()
 	const OID oid384 = ASN1::secp384r1();

 	ECHMQV384 hmqvA384(oid384, true /*client*/);

 

-	success = AuthenticatedKeyAgreementWithRolesValidate(hmqvA384, hmqvB384) && success;

+	fail = !AuthenticatedKeyAgreementWithRolesValidate(hmqvA384, hmqvB384);

+	success = !fail && success;

+	if (fail == false)

+		std::cout << "passed    authenticated key agreement" << std::endl;

+	else

+		std::cout << "FAILED    authenticated key agreement" << std::endl;

 

 	/////////////////////////

 

@@ -113,7 +123,12 @@ bool ValidateHMQV()
 	const OID oid521 = ASN1::secp521r1();

 	ECHMQV512 hmqvA521(oid521, true /*client*/);

 

-	success = AuthenticatedKeyAgreementWithRolesValidate(hmqvA521, hmqvB521) && success;

+	fail = !AuthenticatedKeyAgreementWithRolesValidate(hmqvA521, hmqvB521);

+	success = !fail && success;

+	if (fail == false)

+		std::cout << "passed    authenticated key agreement" << std::endl;

+	else

+		std::cout << "FAILED    authenticated key agreement" << std::endl;

 

 	return success;

 }

@@ -121,7 +136,7 @@ bool ValidateHMQV()
 bool ValidateFHMQV()

 {

 	std::cout << "\nFHMQV validation suite running...\n\n";

-	bool success = true;

+	bool success = true, fail;

 

 	FileSource f256(DataDir("TestData/fhmqv256.dat").c_str(), true, new HexDecoder);

 	FileSource f384(DataDir("TestData/fhmqv384.dat").c_str(), true, new HexDecoder);

@@ -136,7 +151,12 @@ bool ValidateFHMQV()
 	const OID oid = ASN1::secp256r1();

 	ECFHMQV< ECP >::Domain fhmqvA256(oid, true /*client*/);

 

-	success = AuthenticatedKeyAgreementWithRolesValidate(fhmqvA256, fhmqvB256) && success;

+	fail = !AuthenticatedKeyAgreementWithRolesValidate(fhmqvA256, fhmqvB256);

+	success = !fail && success;

+	if (fail == false)

+		std::cout << "passed    authenticated key agreement" << std::endl;

+	else

+		std::cout << "FAILED    authenticated key agreement" << std::endl;

 

 	/////////////////////////

 

@@ -147,7 +167,12 @@ bool ValidateFHMQV()
 	const OID oid384 = ASN1::secp384r1();

 	ECHMQV384 fhmqvA384(oid384, true /*client*/);

 

-	success = AuthenticatedKeyAgreementWithRolesValidate(fhmqvA384, fhmqvB384) && success;

+	fail = !AuthenticatedKeyAgreementWithRolesValidate(fhmqvA384, fhmqvB384);

+	success = !fail && success;

+	if (fail == false)

+		std::cout << "passed    authenticated key agreement" << std::endl;

+	else

+		std::cout << "FAILED    authenticated key agreement" << std::endl;

 

 	/////////////////////////

 

@@ -158,7 +183,12 @@ bool ValidateFHMQV()
 	const OID oid521 = ASN1::secp521r1();

 	ECHMQV512 fhmqvA521(oid521, true /*client*/);

 

-	success = AuthenticatedKeyAgreementWithRolesValidate(fhmqvA521, fhmqvB521) && success;

+	fail = !AuthenticatedKeyAgreementWithRolesValidate(fhmqvA521, fhmqvB521);

+	success = !fail && success;

+	if (fail == false)

+		std::cout << "passed    authenticated key agreement" << std::endl;

+	else

+		std::cout << "FAILED    authenticated key agreement" << std::endl;

 

 	return success;

 }