//----- Microsoft PUBLICKEYBLOB format ----
public bool DecodeMSPublicKeyBlob(byte[] publickeyblob)
{
PUBKEYBLOBHEADERS pkheaders = new PUBKEYBLOBHEADERS();
int headerslength = Marshal.SizeOf(pkheaders);
IntPtr buffer = Marshal.AllocHGlobal(headerslength);
Marshal.Copy(publickeyblob, 0, buffer, headerslength);
pkheaders = (PUBKEYBLOBHEADERS)Marshal.PtrToStructure(buffer, typeof(PUBKEYBLOBHEADERS));
Marshal.FreeHGlobal(buffer);
//----- basic sanity check of PUBLICKEYBLOB fields ------------
if (pkheaders.bType != PUBLICKEYBLOB)
{
return(false);
}
if (pkheaders.bVersion != CUR_BLOB_VERSION)
{
return(false);
}
if (pkheaders.aiKeyAlg != CALG_RSA_KEYX && pkheaders.aiKeyAlg != CALG_RSA_SIGN)
{
return(false);
}
if (verbose)
{
Console.WriteLine("\n ---- PUBLICKEYBLOB headers ------");
Console.WriteLine(" btype {0}", pkheaders.bType);
Console.WriteLine(" bversion {0}", pkheaders.bVersion);
Console.WriteLine(" reserved {0}", pkheaders.reserved);
Console.WriteLine(" aiKeyAlg 0x{0:x8}", pkheaders.aiKeyAlg);
String magicstring = (new ASCIIEncoding()).GetString(BitConverter.GetBytes(pkheaders.magic));
Console.WriteLine(" magic 0x{0:x8} '{1}'", pkheaders.magic, magicstring);
Console.WriteLine(" bitlen {0}", pkheaders.bitlen);
Console.WriteLine(" pubexp {0}", pkheaders.pubexp);
Console.WriteLine(" --------------------------------");
}
//----- Get public key size in bits -------------
this.keySize = pkheaders.bitlen;
//----- Get public exponent -------------
byte[] exponent = BitConverter.GetBytes(pkheaders.pubexp); //little-endian ordered
Array.Reverse(exponent); //convert to big-endian order
this.keyExponent = exponent;
if (verbose)
{
showBytes("\nPublic key exponent (big-endian order):", exponent);
}
//----- Get modulus -------------
int modulusbytes = (int)pkheaders.bitlen / 8;
byte[] modulus = new byte[modulusbytes];
try
{
Array.Copy(publickeyblob, headerslength, modulus, 0, modulusbytes);
Array.Reverse(modulus); //convert from little to big-endian ordering.
this.keyModulus = modulus;
if (verbose)
{
showBytes("\nPublic key modulus (big-endian order):", modulus);
}
}
catch (Exception)
{
Console.WriteLine("Problem getting modulus from publickeyblob");
return(false);
}
return(true);
}
//----- Microsoft PUBLICKEYBLOB format ----
public bool DecodeMSPublicKeyBlob(byte[] publickeyblob)
{
PUBKEYBLOBHEADERS pkheaders = new PUBKEYBLOBHEADERS() ;
int headerslength = Marshal.SizeOf(pkheaders);
IntPtr buffer = Marshal.AllocHGlobal( headerslength);
Marshal.Copy( publickeyblob, 0, buffer, headerslength );
pkheaders = (PUBKEYBLOBHEADERS) Marshal.PtrToStructure( buffer, typeof(PUBKEYBLOBHEADERS) );
Marshal.FreeHGlobal( buffer );
//----- basic sanity check of PUBLICKEYBLOB fields ------------
if(pkheaders.bType != PUBLICKEYBLOB)
return false;
if(pkheaders.bVersion != CUR_BLOB_VERSION)
return false;
if(pkheaders.aiKeyAlg != CALG_RSA_KEYX && pkheaders.aiKeyAlg != CALG_RSA_SIGN)
return false;
if(verbose)
{
Console.WriteLine("\n ---- PUBLICKEYBLOB headers ------");
Console.WriteLine(" btype {0}", pkheaders.bType);
Console.WriteLine(" bversion {0}", pkheaders.bVersion);
Console.WriteLine(" reserved {0}", pkheaders.reserved);
Console.WriteLine(" aiKeyAlg 0x{0:x8}", pkheaders.aiKeyAlg);
String magicstring = (new ASCIIEncoding()).GetString(BitConverter.GetBytes(pkheaders.magic)) ;
Console.WriteLine(" magic 0x{0:x8} '{1}'", pkheaders.magic, magicstring);
Console.WriteLine(" bitlen {0}", pkheaders.bitlen);
Console.WriteLine(" pubexp {0}", pkheaders.pubexp);
Console.WriteLine(" --------------------------------");
}
//----- Get public key size in bits -------------
this.keySize = pkheaders.bitlen;
//----- Get public exponent -------------
byte[] exponent = BitConverter.GetBytes(pkheaders.pubexp); //little-endian ordered
Array.Reverse(exponent); //convert to big-endian order
this.keyExponent = exponent;
if(verbose)
showBytes("\nPublic key exponent (big-endian order):", exponent);
//----- Get modulus -------------
int modulusbytes = (int)pkheaders.bitlen/8 ;
byte[] modulus = new byte[modulusbytes];
try
{
Array.Copy(publickeyblob, headerslength, modulus, 0, modulusbytes);
Array.Reverse(modulus); //convert from little to big-endian ordering.
this.keyModulus = modulus;
if(verbose)
showBytes("\nPublic key modulus (big-endian order):", modulus);
}
catch(Exception)
{
Console.WriteLine("Problem getting modulus from publickeyblob");
return false;
}
return true;
}
