- Change _connectAndLazySemaphoreInitLock to a SemaphoreSlim and use it in ConnectAsync. - Rename it to _connectLock and only use it for connecting. Replace its other usages (on SessionSemaphore and NextChannelNumber) with Interlocked operations. - Remove AuthenticationConnection semaphore. This static member placed a process-wide limit on the number of connections an application can make. I agree with the argument in https://github.com/sshnet/SSH.NET/issues/409#issuecomment-457415542 (and in several other issues/PRs) that this should not be something that the library attempts to control. The last change broke a few tests which do things like making 100 connections. I was tempted to delete these tests as I don't think they have much value, but instead I just limited their concurrency. Co-authored-by: Wojciech Nagórski <wojtpl2@gmail.com>
SSH.NET
SSH.NET is a Secure Shell (SSH-2) library for .NET, optimized for parallelism.
Introduction
This project was inspired by Sharp.SSH library which was ported from java and it seems like was not supported for quite some time. This library is a complete rewrite, without any third party dependencies, using parallelism to achieve the best performance possible.
Documentation
There is MSDN-style class documentation in a .chm file for each release, which you can find in the Assets section of the latest release page. Please note that you will need to right-click and "unblock" the CHM file after you download it.
Currently (4/18/2020), the documentation is very sparse. Fortunately, there are a large number of tests in Renci.SshNet.Tests that demonstrate usage with working code.
If the test for the functionality you would like to see documented is not complete, then you are cordially invited to read the source, Luke, and highly encouraged to generate a pull request for the implementation of the missing test once you figure things out. 🤓
Features
- Execution of SSH command using both synchronous and asynchronous methods
- Return command execution exit status and other information
- Provide SFTP functionality for both synchronous and asynchronous operations
- Provides SCP functionality
- Provide status report for upload and download sftp operations to allow accurate progress bar implementation
- Remote, dynamic and local port forwarding
- Shell/Terminal implementation
- Specify key file pass phrase
- Use multiple key files to authenticate
- Supports publickey, password and keyboard-interactive authentication methods
- Supports two-factor or higher authentication
- Supports SOCKS4, SOCKS5 and HTTP Proxy
Encryption Method
SSH.NET supports the following encryption methods:
- aes256-ctr
- 3des-cbc
- aes128-cbc
- aes192-cbc
- aes256-cbc
- blowfish-cbc
- twofish-cbc
- twofish192-cbc
- twofish128-cbc
- twofish256-cbc
- arcfour
- arcfour128
- arcfour256
- cast128-cbc
- aes128-ctr
- aes192-ctr
Key Exchange Method
SSH.NET supports the following key exchange methods:
- curve25519-sha256
- curve25519-sha256@libssh.org
- ecdh-sha2-nistp256
- ecdh-sha2-nistp384
- ecdh-sha2-nistp521
- diffie-hellman-group-exchange-sha256
- diffie-hellman-group-exchange-sha1
- diffie-hellman-group16-sha512
- diffie-hellman-group14-sha256
- diffie-hellman-group14-sha1
- diffie-hellman-group1-sha1
Public Key Authentication
SSH.NET supports the following private key formats:
- RSA in OpenSSL PEM and ssh.com format
- DSA in OpenSSL PEM and ssh.com format
- ECDSA 256/384/521 in OpenSSL PEM format
- ECDSA 256/384/521, ED25519 and RSA in OpenSSH key format
Private keys can be encrypted using one of the following cipher methods:
- DES-EDE3-CBC
- DES-EDE3-CFB
- DES-CBC
- AES-128-CBC
- AES-192-CBC
- AES-256-CBC
Host Key Algorithms
SSH.NET supports the following host key algorithms:
- ssh-ed25519
- ecdsa-sha2-nistp256
- ecdsa-sha2-nistp384
- ecdsa-sha2-nistp521
- rsa-sha2-512
- rsa-sha2-256
- ssh-rsa
- ssh-dss
Message Authentication Code
SSH.NET supports the following MAC algorithms:
- hmac-md5
- hmac-md5-96
- hmac-sha1
- hmac-sha1-96
- hmac-sha2-256
- hmac-sha2-256-96
- hmac-sha2-512
- hmac-sha2-512-96
- hmac-ripemd160
- hmac-ripemd160@openssh.com
Framework Support
SSH.NET supports the following target frameworks:
- .NETFramework 4.6.2 (and higher)
- .NET Standard 2.0 and 2.1
- .NET 6 (and higher)
Usage
Multi-factor authentication
Establish a SFTP connection using both password and public-key authentication:
var connectionInfo = new ConnectionInfo("sftp.foo.com",
"guest",
new PasswordAuthenticationMethod("guest", "pwd"),
new PrivateKeyAuthenticationMethod("rsa.key"));
using (var client = new SftpClient(connectionInfo))
{
client.Connect();
}
Verify host identify
Establish a SSH connection using user name and password, and reject the connection if the fingerprint of the server does not match the expected fingerprint:
string expectedFingerPrint = "LKOy5LvmtEe17S4lyxVXqvs7uPMy+yF79MQpHeCs/Qo";
using (var client = new SshClient("sftp.foo.com", "guest", "pwd"))
{
client.HostKeyReceived += (sender, e) =>
{
e.CanTrust = expectedFingerPrint.Equals(e.FingerPrintSHA256);
};
client.Connect();
}
Supporting SSH.NET
Do you or your company rely on SSH.NET in your projects? If you want to encourage us to keep on going and show us that you appreciate our work, please consider becoming a sponsor through GitHub Sponsors.