/// <summary>
/// Decrypts the encrypted message if it is a symmetrically encrypted
/// message with the passphrase given as argument.
/// </summary>
/// <param name="strPassphrase">The passphrase that was used to encrypt
/// the message</param>
/// <returns>Returns the message that was encrypted. Usually this is
/// an compressed or literal message.</returns>
/// <remarks>No remarks</remarks>
public Message Decrypt(string strPassphrase)
{
if (esKeys.SymKeys.Count == 0)
{
throw new Exception("This message is not symmetrically encrypted. Please provide a keyring rather than a passphrase!");
}
Packet[] pContent = new Packet[0];
Packet[] pReturn = new Packet[0];
IEnumerator ieKeys = esKeys.SymKeys.GetEnumerator();
while (ieKeys.MoveNext())
{
SymSessionKeyPacket skpKey = (SymSessionKeyPacket)ieKeys.Current;
byte[] key = skpKey.S2KSpecifier.GetKey(strPassphrase, CipherHelper.CipherKeySize(skpKey.Algorithm));
try {
SymmetricAlgorithm saAlgo = CipherHelper.CreateSymAlgorithm(skpKey.Algorithm);
pContent = sepData.Decrypt(key, saAlgo);
} catch (System.Security.Cryptography.CryptographicException) {}
if (pContent.Length > 0)
{
pReturn = pContent;
}
}
if (pReturn.Length == 0)
{
throw new System.Security.Cryptography.CryptographicException("Wrong passphrase!");
}
// now we need to look what kind of message was hidden in the
// encrypted data
// it can be either a literal message
LiteralMessage lmLiteral = new LiteralMessage();
try {
int iPos = lmLiteral.ParseMessage(pReturn);
return(lmLiteral);
} catch (Exception) {}
// or an compressed Message
CompressedMessage cmCompressed = new CompressedMessage();
try {
int iPos = cmCompressed.ParseMessage(pReturn);
return(cmCompressed);
} catch (Exception) {}
throw new System.ArgumentException("Encrypted package content is not a valid message!");
}
/// <summary>
/// Method handling decrypting and verifying
/// </summary>
/// <param name="bData">data to be decrypted</param>
/// <param name="strPassphrase">passphrase</param>
/// <param name="fileOut">the decrypted file location if one produced</param>
/// <returns>verifying process result</returns>
private string DecryptAndVerify(byte[] bData, string strPassphrase, string fileOut)
{
string strMessage = System.Text.Encoding.UTF8.GetString(bData);
ArmorTypes atType = new ArmorTypes();
string strRest = "";
string strRadix64 = Armor.RemoveArmor(strMessage, ref atType, ref strRest);
if (strRadix64.Length > 0)
bData = Radix64.Decode(strRadix64);
SharpPrivacy.SharpPrivacyLib.OpenPGP.Messages.Message mContent = null;
if (atType == ArmorTypes.OpenPGPSignedMessage) {
string strSignature = "";
string strSignedMessage = Armor.RemoveClearSignatureArmor(strMessage, ref atType, ref strSignature);
strSignedMessage = Radix64.DashUnescape(strSignedMessage);
strSignedMessage = Radix64.TrimMessage(strSignedMessage);
SignedMessage smMessage = new SignedMessage();
Packet[] pPackets;
pPackets = Packet.ParsePackets(strSignature);
if (!(pPackets[0] is SignaturePacket)) {
throw new Exception("Not a valid cleartext signature!");
}
smMessage.Signature = (SignaturePacket)pPackets[0];
LiteralMessage lmMessage = new LiteralMessage(DataFormatTypes.Text);
lmMessage.Text = strSignedMessage;
smMessage.MessageSigned = lmMessage;
mContent = smMessage;
} else {
// let us see what kind of message this is
EncryptedMessage emMessage = new EncryptedMessage();
Packet[] pPackets;
try {
pPackets = Packet.ParsePackets(bData);
try {
emMessage.ParseMessage(pPackets);
if (emMessage.SymmetricallyEncrypted) {
// Query passphrase for symmetrically encrypted message
mContent = emMessage.Decrypt(strPassphrase);
} else {
ulong lKeyID = emMessage.GetFittingKeyID(skrSecretKeyRing);
mContent = emMessage.Decrypt(skrSecretKeyRing, strPassphrase);
}
} catch (Exception) {
mContent = new CompressedMessage();
mContent.ParseMessage(pPackets);
}
while ((!(mContent is LiteralMessage)) && (!(mContent is SignedMessage))) {
if (mContent is CompressedMessage) {
mContent = ((CompressedMessage)mContent).Uncompress();
} else {
throw new Exception("This is not a valid OpenPGP message!");
}
}
} catch (Exception ee) {
throw new Exception("There was an error decrypting your message: " + ee.Message);
}
}
LiteralMessage lmContent = new LiteralMessage();
string strDisplay = "";
if (mContent is SignedMessage) {
SignedMessage smContent = (SignedMessage)mContent;
lmContent = smContent.MessageSigned;
strDisplay += "*** OpenPGP Signed Message ***\r\n";
strDisplay += "*** Signature Status: " + smContent.Verify(pkrPublicKeyRing) + " ***\r\n";
strDisplay += "*** Signing Key Dec: " + smContent.Signature.KeyID.ToString() + " ***\r\n";
strDisplay += "*** Signing Key Hex: " + smContent.Signature.KeyID.ToString("x") + " ***\r\n";
try {
try {
strDisplay += "*** Signing Key Expiration: " + pkrPublicKeyRing.Find(smContent.Signature.KeyID,true).KeyExpirationTime + " ***\r\n";
} catch(Exception e) {
if(e.Message.Equals("never"))
strDisplay += "*** Signing Key Expiration: "+e.Message+" ***\r\n";
else
throw new Exception("Signing_Key_Not_Available");
}
try {
strDisplay += "*** Signing Key Revoked: "+ this.pkrPublicKeyRing.isRevoked(smContent.Signature.KeyID) +" ***\r\n";
} catch(Exception e) {
string msg = e.Message;
strDisplay += "*** Signing Key Revoked: Revocation_Key_Not_Available ***\r\n";
}
} catch (Exception e) {
string warn = e.Message;
strDisplay += "*** Signing Key Expiration: " + SignatureStatusTypes.Signing_Key_Not_Available + " ***\r\n";
}
strDisplay += "*** Signing Date: " + smContent.Signature.TimeCreated.ToString() + "***\r\n\r\n";
} else if (mContent is LiteralMessage) {
lmContent = (LiteralMessage)mContent;
strDisplay += "*** OpenPGP Encrypted Message ***\r\n\r\n";
} else {
throw new Exception("An error occured: Could not find an encrypted or signed message!");
}
if (lmContent.DataFormat == DataFormatTypes.Text) {
strDisplay += lmContent.Text;
strDisplay += "\r\n\r\n*** End OpenPGP Message ***\r\n";
if(fileOut != null && fileOut != "") {
System.IO.FileStream fsOut = new FileStream(fileOut, FileMode.Create);
System.IO.BinaryWriter bwOut = new BinaryWriter(fsOut);
bwOut.Write(lmContent.Binary);
bwOut.Close();
fsOut.Close();
}
} else {
System.IO.FileStream fsOut = new FileStream(fileOut, FileMode.Create);
System.IO.BinaryWriter bwOut = new BinaryWriter(fsOut);
bwOut.Write(lmContent.Binary);
bwOut.Close();
fsOut.Close();
}
return strDisplay;
}
/// <summary>
/// Decrypts the encrypted message if it is a symmetrically encrypted
/// message with the passphrase given as argument.
/// </summary>
/// <param name="strPassphrase">The passphrase that was used to encrypt
/// the message</param>
/// <returns>Returns the message that was encrypted. Usually this is
/// an compressed or literal message.</returns>
/// <remarks>No remarks</remarks>
public Message Decrypt(string strPassphrase)
{
if (esKeys.SymKeys.Count == 0)
throw new Exception("This message is not symmetrically encrypted. Please provide a keyring rather than a passphrase!");
Packet[] pContent = new Packet[0];
Packet[] pReturn = new Packet[0];
IEnumerator ieKeys = esKeys.SymKeys.GetEnumerator();
while (ieKeys.MoveNext()) {
SymSessionKeyPacket skpKey = (SymSessionKeyPacket)ieKeys.Current;
byte[] key = skpKey.S2KSpecifier.GetKey(strPassphrase, CipherHelper.CipherKeySize(skpKey.Algorithm));
try {
SymmetricAlgorithm saAlgo = CipherHelper.CreateSymAlgorithm(skpKey.Algorithm);
pContent = sepData.Decrypt(key, saAlgo);
} catch (System.Security.Cryptography.CryptographicException) {}
if (pContent.Length > 0) {
pReturn = pContent;
}
}
if (pReturn.Length == 0)
throw new System.Security.Cryptography.CryptographicException("Wrong passphrase!");
// now we need to look what kind of message was hidden in the
// encrypted data
// it can be either a literal message
LiteralMessage lmLiteral = new LiteralMessage();
try {
int iPos = lmLiteral.ParseMessage(pReturn);
return lmLiteral;
} catch (Exception) {}
// or an compressed Message
CompressedMessage cmCompressed = new CompressedMessage();
try {
int iPos = cmCompressed.ParseMessage(pReturn);
return cmCompressed;
} catch (Exception) {}
throw new System.ArgumentException("Encrypted package content is not a valid message!");
}
/// <summary>
/// Decrypts the current encrypted message using the secret keys
/// in skrKeyRing and the given passphrase.
/// </summary>
/// <param name="skrKeyRing">The secret keyring containing all the
/// secret keys know to the sytem.</param>
/// <param name="strPassphrase">The passphrase that was used to
/// encrypt the secret key material in the key that decrypts
/// the message.</param>
/// <returns>Returns the message that was encrypted. Usually this is
/// an compressed or literal message.</returns>
/// <remarks>No remarks</remarks>
public Message Decrypt(SecretKeyRing skrKeyRing, string strPassphrase)
{
TransportableSecretKey tskSecretKey = new TransportableSecretKey();
AsymSessionKeyPacket askpSessionKey = new AsymSessionKeyPacket();
bool bFound = false;
// let's see, if we can find a fitting Sessionkey packet
IEnumerator ieSessionkeys = esKeys.AsymKeys.GetEnumerator();
while (ieSessionkeys.MoveNext())
{
if (!(ieSessionkeys.Current is AsymSessionKeyPacket))
{
throw new Exception("Strange Error!");
}
AsymSessionKeyPacket askpKey = (AsymSessionKeyPacket)ieSessionkeys.Current;
ulong lKeyID = askpKey.KeyID;
TransportableSecretKey tskKey = skrKeyRing.Find(lKeyID);
if (tskKey != null)
{
bFound = true;
tskSecretKey = tskKey;
askpSessionKey = askpKey;
}
}
if (!bFound)
{
throw new Exception("No fitting secret key was found to decrypt the message!");
}
askpSessionKey.DecryptSessionKey(tskSecretKey, strPassphrase);
byte[] bKey = askpSessionKey.SessionKey;
Packet[] pContent = new Packet[0];
try {
SymmetricAlgorithm saAlgo = CipherHelper.CreateSymAlgorithm(askpSessionKey.SymmetricAlgorithm);
pContent = sepData.Decrypt(bKey, saAlgo);
} catch (Exception e) {
throw new System.Exception("Decryption of the Message failed: " + e.Message);
}
// now we need to look what kind of message was hidden in the
// encrypted data
// it can be either a literal message
LiteralMessage lmLiteral = new LiteralMessage();
try {
int iPos = lmLiteral.ParseMessage(pContent);
return(lmLiteral);
} catch (Exception) {}
// or an compressed Message
CompressedMessage cmCompressed = new CompressedMessage();
try {
int iPos = cmCompressed.ParseMessage(pContent);
return(cmCompressed);
} catch (Exception) {}
throw new System.ArgumentException("Encrypted package content is not a valid message!");
}
/// <summary>
/// Decrypts the current encrypted message using the secret keys
/// in skrKeyRing and the given passphrase.
/// </summary>
/// <param name="skrKeyRing">The secret keyring containing all the
/// secret keys know to the sytem.</param>
/// <param name="strPassphrase">The passphrase that was used to
/// encrypt the secret key material in the key that decrypts
/// the message.</param>
/// <returns>Returns the message that was encrypted. Usually this is
/// an compressed or literal message.</returns>
/// <remarks>No remarks</remarks>
public Message Decrypt(SecretKeyRing skrKeyRing, string strPassphrase)
{
TransportableSecretKey tskSecretKey = new TransportableSecretKey();
AsymSessionKeyPacket askpSessionKey = new AsymSessionKeyPacket();
bool bFound = false;
// let's see, if we can find a fitting Sessionkey packet
IEnumerator ieSessionkeys = esKeys.AsymKeys.GetEnumerator();
while (ieSessionkeys.MoveNext()) {
if (!(ieSessionkeys.Current is AsymSessionKeyPacket))
throw new Exception("Strange Error!");
AsymSessionKeyPacket askpKey = (AsymSessionKeyPacket)ieSessionkeys.Current;
ulong lKeyID = askpKey.KeyID;
TransportableSecretKey tskKey = skrKeyRing.Find(lKeyID);
if (tskKey != null) {
bFound = true;
tskSecretKey = tskKey;
askpSessionKey = askpKey;
}
}
if (!bFound)
throw new Exception("No fitting secret key was found to decrypt the message!");
askpSessionKey.DecryptSessionKey(tskSecretKey, strPassphrase);
byte[] bKey = askpSessionKey.SessionKey;
Packet[] pContent = new Packet[0];
try {
SymmetricAlgorithm saAlgo = CipherHelper.CreateSymAlgorithm(askpSessionKey.SymmetricAlgorithm);
pContent = sepData.Decrypt(bKey, saAlgo);
} catch (Exception e) {
throw new System.Exception("Decryption of the Message failed: " + e.Message);
}
// now we need to look what kind of message was hidden in the
// encrypted data
// it can be either a literal message
LiteralMessage lmLiteral = new LiteralMessage();
try {
int iPos = lmLiteral.ParseMessage(pContent);
return lmLiteral;
} catch (Exception) {}
// or an compressed Message
CompressedMessage cmCompressed = new CompressedMessage();
try {
int iPos = cmCompressed.ParseMessage(pContent);
return cmCompressed;
} catch (Exception) {}
throw new System.ArgumentException("Encrypted package content is not a valid message!");
}