(Mono C#) Get PuTTY Public Key from Private PPK

Demonstrates how to get a PuTTY public key from the PPK private key.

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// Load a .ppk PuTTY private key.
Chilkat.SshKey puttyKey = new Chilkat.SshKey();
string ppkText = puttyKey.LoadText("qa_data/ppk/putty_private_secret.ppk");

// The ppkText contains this content:

// 	PuTTY-User-Key-File-2: ssh-rsa
// 	Encryption: aes256-cbc
// 	Comment: rsa-key-20170126
// 	Public-Lines: 6
// 	AAAAB3NzaC1yc2EAAAABJQAAAQEAx+52s7vvaZ8rT2UdFZWlSUVDHDQ+5ZRFvgRW
// 	6nm2sO1c9WqNg7u2PQL4jeKSDX2XWcMnpleALz2x8Rr4rMy5E1iZzvWov8VtFd8l
// 	fa9HOkgEeJB3VFuYR3NlnD3eyCoYJYPVpHJHrIeui2WZs5vQ76HDe+th8+z5Ald4
// 	zPw3p2c6ZJpBrkSBM67hWokoBDi23c7NhszDHhJBrv+B98cQxnagI1PUKqN7E8Vg
// 	bNtBI8beIMHyI69up9G1AXSEi0cGIjYNx9RNUPau1mRk/SvfqxgWkAjM005lj7hc
// 	bOsjbdKK3T2NtrKTaYjEiXlEXcj1iGuApsD/m73pYaEJB3Nd7w==
// 	Private-Lines: 14
// 	MoaDbq0owouN/7Z9Pga0favDhM2bSEgMErJBxdDmNUXIVVcUoLiD/Ps1RA+BeBBX
// 	wxqKUt9PqLy/pnafPR/i2xjJiQtQ0CWkPxND16Gi1dqLzmbQYYl1ev4+LzuG0zNX
// 	HDGMvRiwagY7mY+F1tUjBYfOL6z8XHw4m40YcY1QorOO+0MMzAVT5Hkg8YyXW209
// 	B/V/LRADFMVA2BlL39y11cb5ZpFStPH/waYUMY+2w1ZmJZ7dcRoMjuKmY+YE/tUx
// 	n9X3P0qTNSbw6e6sMG3Dhr1vfoJUQWApUliD6GpUiCeIvXBcVqG8Vsfq9XADsPl0
// 	+nFAwjSZflywcB7/FwhGb7q5UmcJK06SzoMl7Og5e3g7NCs3yNNQIv+qCpDjhxrA
// 	hpT03mbipu7OXCZDeUwUhMGJAmYHE5iqm1rPCsSVbaMgpxhCWf01Cx4gLx3aMvn4
// 	MdylA31GuL3wSxcWTslrOI8+449lZN/qZEnGEZkYTrnlu123jTqsAWMMtuHSz2Ig
// 	6GA89oTdlppkNflhNH3OJ85kMUrc3p/ZBMdndz8jTDTljmJjHR5oNMoShFof115A
// 	nWjUHqBwCgcubLYyH3afDvBTOhtl0tJ9Oby0wJlOAGnCXiPSDbF/y7J7xml/PS9t
// 	XlSVNxtAY15NDO6Fp96sBVfKuJsfJ90PzdBom4ikIuf7sMwtElrHHLuYfcXJQYLp
// 	G5jBmqDgnirosVPEBIxlxFzz/HCRmdU+tsYg46gqI4R5UpKUe8WSaJoZkDGsrqhm
// 	e+1SJaBuafR4v2bx/bV414Hg7LGQosK2S3crxH4UgZl+g02vWznZfBH+9CmHvKDR
// 	AxfcKOTzsaILKJtQPV81lmJ45sARYMcB5jMiE4kBg56hiXouChsvKkm55WVcW1E+
// 	Private-MAC: 17512c9f7582c1d9c3ae2b01b4d67a6b1dbd1d0e

// "secret" is the actual password for the above PPK.
puttyKey.Password = "secret";
bool success = puttyKey.FromPuttyPrivateKey(ppkText);
if (success != true) {
    Debug.WriteLine(puttyKey.LastErrorText);
    return;
}

// There are two common SSH public key formats.
// This example will convert to both.

// 1) Convert to an OpenSSH public key
// 
string strPubKey1 = puttyKey.ToOpenSshPublicKey();
Debug.WriteLine(strPubKey1);

// strPubKey1 contains:
// 
// ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAQEAx+52s7vvaZ8rT2UdFZWlSUVDHDQ+5ZRFvgRW6nm2sO1c9WqNg7u2PQL4jeKSDX2XWcMnpleALz2x8Rr4rMy5E1iZzvWov8VtFd8lfa9HOkgEeJB3VFuYR3NlnD3eyCoYJYPVpHJHrIeui2WZs5vQ76HDe+th8+z5Ald4zPw3p2c6ZJpBrkSBM67hWokoBDi23c7NhszDHhJBrv+B98cQxnagI1PUKqN7E8VgbNtBI8beIMHyI69up9G1AXSEi0cGIjYNx9RNUPau1mRk/SvfqxgWkAjM005lj7hcbOsjbdKK3T2NtrKTaYjEiXlEXcj1iGuApsD/m73pYaEJB3Nd7w== rsa-key-20170126

// 2) Convert to an RFC 4716 SSH public key PEM
// 
string strPubKey2 = puttyKey.ToRfc4716PublicKey();
Debug.WriteLine(strPubKey2);

// strPubKey2 contains:
// 
// ---- BEGIN SSH2 PUBLIC KEY ----
// Comment: "rsa-key-20170126"
// AAAAB3NzaC1yc2EAAAABJQAAAQEAx+52s7vvaZ8rT2UdFZWlSUVDHDQ+5ZRFvgRW
// 6nm2sO1c9WqNg7u2PQL4jeKSDX2XWcMnpleALz2x8Rr4rMy5E1iZzvWov8VtFd8l
// fa9HOkgEeJB3VFuYR3NlnD3eyCoYJYPVpHJHrIeui2WZs5vQ76HDe+th8+z5Ald4
// zPw3p2c6ZJpBrkSBM67hWokoBDi23c7NhszDHhJBrv+B98cQxnagI1PUKqN7E8Vg
// bNtBI8beIMHyI69up9G1AXSEi0cGIjYNx9RNUPau1mRk/SvfqxgWkAjM005lj7hc
// bOsjbdKK3T2NtrKTaYjEiXlEXcj1iGuApsD/m73pYaEJB3Nd7w==
// ---- END SSH2 PUBLIC KEY ----