Does SSH.NET only support the OpenSSH private key? If not, what are the limitations?

Question

This is not indicated in the manual, but some Googling have returned pages from the end of the decade (for example, this ), suggesting that at least this was the case. We have a code like this:

var privateKeyAuthenticationMethod =
    new PrivateKeyAuthenticationMethod(userName, new PrivateKeyFile(privateKeyLocation));
var connInfo =
    new ConnectionInfo(
        ftpSettings.HostAddress, ftpSettings.UserName, privateKeyAuthenticationMethod);
using (var client = new SftpClient(connInfo))
{
    client.Connect();
    client.UploadFile(memStreamData, destination);
}

This intercepts the private key that we successfully used through SCP2 (Secure Copy 2, as described in detail here ) - this is the 2048 DSA, which is listed as valid in the SSH.NET documentation. The key uses the ssh.com format, for example:

---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----
Subject: <FID name>
Comment: "2048-bit dsa, <FID name>@<Server name>, Mon Apr 24 201\
 7 15:49:36 +0100"
<ENCRYPTED KEY>
---- END SSH2 ENCRYPTED PRIVATE KEY ----

However, in the part of processing the SSH.NET secret key, there is Regexone that does not match our private key and therefore throws an exception:

ERROR 2017-05-10 15:31:43 UTC [T: 474] – Invalid private key file.
ERROR 2017-05-10 15:31:43 UTC [T: 474] – at Renci.SshNet.PrivateKeyFile.Open(Stream privateKey, String passPhrase)

, OpenSSH, , , - .

- , Private Key SSH.NET, ? , , SSH.NET - SFTP, .

Answer 1

PrivateKeyFile:

RSA DSA OpenSSH, ssh.com.

---

ssh.com:

---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----
Comment: "dsa-key-20170511"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---- END SSH2 ENCRYPTED PRIVATE KEY ----

SSH.NET 2016.0.0 PrivateKeyFile .

---

, PrivateKeyFile, - Subject:. .

, " ", :

string key = File.ReadAllText(@"C:\path\key");
Regex removeSubjectRegex = new Regex("Subject:.*[\r\n]+", RegexOptions.IgnoreCase);
key = removeSubjectRegex.Replace(key, "");
MemoryStream buf = new MemoryStream(Encoding.UTF8.GetBytes(key));
PrivateKeyFile privateKeyFile = new PrivateKeyFile(buf);