SKALE-4472 change api to receive only string as input

skalenetwork · Aug 18, 2021 · 00c75c6 · 00c75c6
1 parent 2d5635c
commit 00c75c6
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Showing 5 changed files with 51 additions and 24 deletions.
diff --git a/test/unit_tests_te.cpp b/test/unit_tests_te.cpp
@@ -247,7 +247,16 @@ BOOST_AUTO_TEST_CASE( EncryptionCipherToString ) {
 
     libff::alt_bn128_G2 public_key = secret_key * libff::alt_bn128_G2::one();
 
-    auto ciphertext_string = te_instance.encryptMessage( message, public_key );
+    auto str = crypto::ThresholdUtils::G2ToString( public_key, 16 );
+    std::string common_public_str = "";
+    for ( auto& elem : str ) {
+        while ( elem.size() < 64 ) {
+            elem = "0" + elem;
+        }
+        common_public_str += elem;
+    }
+
+    auto ciphertext_string = te_instance.encryptMessage( message, common_public_str );
 
     auto ciphertext_with_aes = te_instance.aesCiphertextFromString( ciphertext_string );
 

diff --git a/threshold_encryption/threshold_encryption.cpp b/threshold_encryption/threshold_encryption.cpp
@@ -145,7 +145,8 @@ std::pair< Ciphertext, std::vector< uint8_t > > TE::encryptWithAES(
 }
 
 std::string TE::encryptMessage(
-    const std::string& message, const libff::alt_bn128_G2& common_public ) {
+    const std::string& message, const std::string& common_public_str ) {
+    libff::alt_bn128_G2 common_public = ThresholdUtils::stringToG2( common_public_str );
     auto ciphertext_with_aes = encryptWithAES( message, common_public );
     return aesCiphertextToString( ciphertext_with_aes.first, ciphertext_with_aes.second );
 }
@@ -338,27 +339,9 @@ std::pair< Ciphertext, std::vector< uint8_t > > TE::aesCiphertextFromString(
         throw ThresholdUtils::IncorrectInput( "Bad aes_cipher provided" );
     }
 
-    std::vector< std::string > coords_u( 4 );
-    coords_u[0] = u_str.substr( 0, 64 );
-    coords_u[1] = u_str.substr( 64, 64 );
-    coords_u[2] = u_str.substr( 128, 64 );
-    coords_u[3] = u_str.substr( 192, std::string::npos );
-
-    libff::alt_bn128_G2 U;
-    U.Z = libff::alt_bn128_Fq2::one();
-    U.X.c0 = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( coords_u[0] ).c_str() );
-    U.X.c1 = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( coords_u[1] ).c_str() );
-    U.Y.c0 = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( coords_u[2] ).c_str() );
-    U.Y.c1 = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( coords_u[3] ).c_str() );
-
-    std::vector< std::string > coords_w( 2 );
-    coords_w[0] = w_str.substr( 0, 64 );
-    coords_w[1] = w_str.substr( 64, std::string::npos );
-
-    libff::alt_bn128_G1 W;
-    W.Z = libff::alt_bn128_Fq::one();
-    W.X = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( coords_w[0] ).c_str() );
-    W.Y = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( coords_w[1] ).c_str() );
+    libff::alt_bn128_G2 U = ThresholdUtils::stringToG2( u_str );
+
+    libff::alt_bn128_G1 W = ThresholdUtils::stringToG1( w_str );
 
     std::string V;
     V.resize( ( v_str.size() - 1 ) / 2 );

diff --git a/threshold_encryption/threshold_encryption.h b/threshold_encryption/threshold_encryption.h
@@ -49,7 +49,7 @@ class TE {
         const std::string& message, const libff::alt_bn128_G2& common_public );
 
     static std::string encryptMessage(
-        const std::string& message, const libff::alt_bn128_G2& common_public );
+        const std::string& message, const std::string& common_public );
 
     static libff::alt_bn128_G2 getDecryptionShare(
         const Ciphertext& ciphertext, const libff::alt_bn128_Fr& secret_key );

diff --git a/tools/utils.cpp b/tools/utils.cpp
@@ -100,6 +100,37 @@ std::string ThresholdUtils::convertHexToDec( const std::string& hex_str ) {
     return output;
 }
 
+libff::alt_bn128_G2 ThresholdUtils::stringToG2( const std::string& str ) {
+    if ( str.size() != 256 ) {
+        throw IncorrectInput("Wrong string size to convert to G2");
+    }
+
+    libff::alt_bn128_G2 ret;
+
+    ret.Z = libff::alt_bn128_Fq2::one();
+
+    ret.X.c0 = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( str.substr( 0, 64 ) ).c_str() );
+    ret.X.c1 = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( str.substr( 64, 64 ) ).c_str() );
+    ret.Y.c0 = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( str.substr( 128, 64 ) ).c_str() );
+    ret.Y.c1 = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( str.substr( 192, std::string::npos ) ).c_str() );
+
+    return ret;
+}
+
+libff::alt_bn128_G1 ThresholdUtils::stringToG1( const std::string& str ) {
+    if ( str.size() != 128 ) {
+        throw IncorrectInput("Wrong string size to convert to G1");
+    }
+
+    libff::alt_bn128_G1 ret;
+
+    ret.Z = libff::alt_bn128_Fq::one();
+    ret.X = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( str.substr( 0, 64 ) ).c_str() );
+    ret.Y = libff::alt_bn128_Fq( ThresholdUtils::convertHexToDec( str.substr( 64, 64 ) ).c_str() );
+
+    return ret;
+}
+
 std::vector< libff::alt_bn128_Fr > ThresholdUtils::LagrangeCoeffs(
     const std::vector< size_t >& idx, size_t t ) {
     if ( idx.size() < t ) {

diff --git a/tools/utils.h b/tools/utils.h
@@ -109,6 +109,10 @@ class ThresholdUtils {
 
     static std::vector< std::string > G2ToString( libff::alt_bn128_G2 elem, int base = 10 );
 
+    static libff::alt_bn128_G2 stringToG2( const std::string& str );
+
+    static libff::alt_bn128_G1 stringToG1( const std::string& str );
+
     static std::string convertHexToDec( const std::string& hex_str );
 
     static bool checkHex( const std::string& hex );