* Curve25519 KEX is now based on BouncyCastle instead of Chaos.NaCl
* Abstract SecureRandom
---------
Co-authored-by: Wojciech Nagórski <wojtpl2@gmail.com>
This drops some of the algorithms long-considered legacy/insecure.
The idea is both to improve the theoretical security of the library by not offering
these algorithms, and to improve the practical security of the library by not having
hand-written, barely tested crypto code.
The overarching goal is for the library to have minimal exposure to crypto
implementation, relying firstly on the .NET base libraries, and secondly on
third-party providers, such as BouncyCastle.
This change covers deleting the cipher algorithms arcfour, blowfish, twofish, cast.
It covers deleting the MD5-based and truncated HMAC algorithms.
These were all disabled in OpenSSH server (sshd) in 2014[^1]:
> sshd(8): The default set of ciphers and MACs has been altered to
> remove unsafe algorithms. In particular, CBC ciphers and arcfour*
> are disabled by default.
>
> The full set of algorithms remains available if configured
> explicitly via the Ciphers and MACs sshd_config options.
and in the client in 2016[^2]:
> This release disables a number of legacy cryptographic algorithms
> by default in ssh:
>
> * Several ciphers blowfish-cbc, cast128-cbc, all arcfour variants
> and the rijndael-cbc aliases for AES.
>
> * MD5-based and truncated HMAC algorithms.
>
> These algorithms are already disabled by default in sshd.
This change also drops PKCS5Padding, which is a line-for-line copy of PKCS7Padding,
and StreamCipher, which is now unused (and useless anyway).
[^1]: https://www.openssh.com/txt/release-6.7
[^2]: https://www.openssh.com/txt/release-7.2
Co-authored-by: Wojciech Nagórski <wojtpl2@gmail.com>
* Replace internal BouncyCastle with NuGet package
* fix NullReference in KeyExchangeECDH
for some reason d24fe2006f introduced
its own names here which (as far as I can see) were never part
of the original BouncyCastle.
Switched to the correct names.
* Update to BouncyCastle 2.3.1
* Update to BouncyCastle 2.4.0
* fix Conflict between Zlib class and BouncyCastle namespace
CA1724: The type name Zlib conflicts in whole or in part with the namespace name 'Org.BouncyCastle.Utilities.Zlib'. Change either name to eliminate the conflict.
We can't change either, so suppress the warning.
---------
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
.NET 9 Preview 6 now also scans transitive dependencies, which
causes a build failure in the test projects:
warning NU1902: Package 'BouncyCastle.Cryptography' 2.2.1 has a known moderate severity vulnerability, https://github.com/advisories/GHSA-8xfc-gm6g-vgpv
Don't treat these as errors and update Testcontainers to fix the warning.
* Ref System.Memory for net462 and netstandard2.0.
Use System.Buffers.Binary.BinaryPrimitives instead of Renci.SshNet.Common.Pack
* Remove unnecessary `AsSpan()`
* Apply suggestions from code review
* that's what I get for being lazy
---------
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
Co-authored-by: Robert Hague <rh@johnstreetcapital.com>
* Add SshCommand.ExecuteAsync
After the previous change (#1423), this basically entails swapping out the
IAsyncResult for a TaskCompletionSource and hooking up the cancellation/timeout
logic.
As with the prior Begin/End implementation, the initiation of the command
(SendExecRequest) happens synchronously, so there's a bit of room for improvement
there, but otherwise it is the Task-based async that we know and like.
I chose to make it void (Task)- returning instead of string like in the existing
overloads, so that OutputStream is not automatically consumed (and encoded as a
string) when that may not be desired. As in #650, I was initially considering
changing the other overloads to be void-returning as well, but decided that it was
not worth the break since most people will probably want to change over to
ExecuteAsync anyway.
* Update examples
---------
Co-authored-by: Wojciech Nagórski <wojtpl2@gmail.com>
The library currently performs a DNS lookup of the desired host, takes the first
returned IP address and connects to that. Instead, we can just pass the hostname
down to System.Net.Sockets which will do the right thing, potentially trying
multiple addresses if needed.
Co-authored-by: Wojciech Nagórski <wojtpl2@gmail.com>
* On SOCKS5 proxy:
The library always resolves the hostname to the IP. Some SOCKS5 proxies don't allow you to specify the IP, they want to resolve the hostname themselves.
The patch sends the proxy the same specified value, IP, or hostname.
* refactor
---------
Co-authored-by: Jordi Vaca <jjvaca@indra.es>
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Updated NETCONF framing protocol detection to check both client & server capabilities
This fixes an issue where the NetConfSession would expect the
framing protocol to be used if ServerCapabilities contained 1.1,
however the server would actually be using the legacy protocol as
the client only advertises support for 1.0.
* fix NETCONF to comply with RFC6242 for framing protocol
* netcconf client - fix null ptr exception on dispose
* netcconf client - provide example usage in xml doc
* add comment
---------
Co-authored-by: Jason Larke <jason.larke@curtin.edu.au>
Co-authored-by: Todd Schavey <todd.schavey@ge.com>
Co-authored-by: Robert Hague <rh@johnstreetcapital.com>
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Updated NETCONF framing protocol detection to check both client & server capabilities
This fixes an issue where the NetConfSession would expect the
framing protocol to be used if ServerCapabilities contained 1.1,
however the server would actually be using the legacy protocol as
the client only advertises support for 1.0.
* add comment
---------
Co-authored-by: Jason Larke <jason.larke@curtin.edu.au>
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Support creating Shell(Stream) without PTY
Fixes https://github.com/sshnet/SSH.NET/issues/1418
* Add integration test for "PermitTTY no"
* Fix Integration Test
* Remove duplicate shell request
* Put common operations in a shared constructor. Update xml doc comments.
* Update comments and method overriding
* Update per code review
* Update integration tests
* Renaming
* Make `bufferSize` optional
* Try fix the test
* Update per code review
* try agian
* try again
* docs
* doc
---------
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* fix flaky SFTP file time tests
These asserts currently assume that DateTime.Now and the
creation timestamp on the server happen within the same second.
Note that I didn't change the asserts below where an explicit
timestamp is set. From my understanding, these should not be affected.
example: https://ci.appveyor.com/project/drieseng/ssh-net/builds/49850731/job/u6lk0cyipbxkp4jd
* remove asserts
Apply similar treatment to PipeStream as #1322 did to ShellStream
PipeStream now behaves much more Stream-like. In particular, it performs partial
reads (instead of blocking until a certain amount of data is available), blocks
until data is available (instead of returning 0 prematurely) and removes the
Stream-unlike properties `BlockLastReadBuffer` and `MaxBufferLength`.
Sadly I gave up trying to make a benchmark compatible with all the quirks of the
previous implementation, but a dumb throughput test (reading and writing simultaneously)
shows about 5.2GB/s with this implementation compared to 140MB/s previously.
Some cleanup of its usage in the library followed.
Co-authored-by: Wojciech Nagórski <wojtpl2@gmail.com>
* Enable nullable on NetConf/Scp/SshClient
* fix formatting
* improve directoryCounter check
* disable nullable warnings on old frameworks
since the libraries are missing a lot of nullable attributes
in the old frameworks, this causes a lot of false positive
nullable warnings.
Simply disable these warnings for old frameworks.
* fix flaky Sftp_BeginUploadFile test
this test can randomly fail because it assumes that the callback
has been called when the AsyncWaitHandle was set. But this is not
necessarily the case because AsyncResult.SetAsCompleted does it
the other way around.
example: https://ci.appveyor.com/project/drieseng/ssh-net/builds/49831002/job/1237d4lg46j22pf0
* use ManualResetEventSlim
---------
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* fix flaky ReceiveOnServerSocketShouldReturnZero test
ReceiveOnServerSocketShouldReturnZero assumed that the disconnect
already happened on the server side, but it never waits for this.
This could cause ServerSocket.Receive to still return valid data
and fail the test.
example: https://ci.appveyor.com/project/drieseng/ssh-net/builds/49836561/job/wen5tjd1c7wgxrfh
* Update test/Renci.SshNet.Tests/Classes/SessionTest_Connected_Disconnect.cs
---------
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Preparation to enforce formatting and style in CI
- enabled IDE0055 to enforce formatting on build
- disabled SA1137 and SA1025 because they are already
covered by IDE0055
- disabled SA1021 because it conflicts with csharp_space_after_cast
* Cleanup formatting and style on codebase
This commit has no manual changes, it is the result
of running "dotnet format whitespace" and "dotnet format style"
* new formatting fixes after merge
* appveyor: set git autocrlf
as suggested by sharwell to hopefully fix Windows CI.
* use autocrlf input
to hopefully fix Linux tests
* fix formatting
* use autocrlf input for Linux only
* set csharp_space_after_cast to false
* Revert SA1021 suppression
---------
Co-authored-by: Robert Hague <rh@johnstreetcapital.com>
- Update README to point to https://sshnet.github.io/SSH.NET rather than the CHM file
- Add a CONTRIBUTING.md with some how-tos
For https://sshnet.github.io/SSH.NET:
- Use the repo README as the landing page to keep them in sync
- Combine the API-per-TFM pages to just one "API" page
- Add a couple more examples
- Add a GitHub link in the header.
* Tweak AsyncSocketListener in tests
Some CI runs have been crashing lately from within AsyncSocketListener.
This moves a bit of disconnection & exception handling around. It probably won't
fix the underlying tests which would have otherwise failed, but it might stop the
process from outright crashing.
Also reference the same code for the integration tests.
* Simplify the diff
* Stabilise a couple of tests
* Use BCL for RSA
* Restore benchmark (with quirks for old code)
* Fixup benchmark (remove compatibility with old code)
* cosmetic tweaks
* Add a regression test for #1388
* Fix SocketAsyncEventArgsAwaitable calling continuation multiple times
* Use Interlocked.Exchange
---------
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Add timeouts when reading from sockets in Socks5Connector
* Add a Socks5 timeout test for a connection reply
---------
Co-authored-by: Wojciech Nagórski <wojtpl2@gmail.com>
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Implement OpenSSH strict key exchange extension
* The pseudo-algorithm
is only valid in the initial SSH2_MSG_KEXINIT and MUST be ignored
if they are present in subsequent SSH2_MSG_KEXINIT packets.
* Only send strict kex pseudo algorithm for the first kex.
Strictly disable non-kex massages in strict kex mode.
* Unit tests for strict kex
* More unit tests
* More unit tests
* Correct file name
* Update SessionTest_ConnectingBase.cs
* More unit tests
* Delete SessionTest_Connecting_ServerSendsMaxIgnoreMessagesBeforeKexInit.cs
* Add a comment about throwing exception when inbound sequence number is about to wrap during init kex.
* Delete SessionTest_Connecting_ServerSendsDebugMessageAfterKexInit_NoStrictKex.cs
* Fix build
* Update test/Renci.SshNet.Tests/Classes/SessionTest_Connected.cs
---------
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Init AeadCipher
* Move AeadCipher to parent folder. Move EncryptBlock/DecryptBlock from SymmetricCipher to BlockCipher
* simplify parameter name
* Implement AesGcmCipher
* Update README
* Remove protected IV from AeadCipher; Set offset to outbound sequence just like other ciphers
* Rename associatedData to packetLengthField
* Use Span<byte> to avoid unnecessary allocations
* Use `Span` to improve performance when `IncrementCounter()`
* Add `IsAead` property to `CipherInfo`. Include packet length field and tag field in offset and length when call AesGcm's `Decrypt(...)` method. Do not determine HMAC if cipher is AesGcm during kex.
* Fix build
* Fix UT
* Check `AesGcm.IsSupported` before add to the `Encryptions` collection.
Guard AES-GCM with `NET6_0_OR_GREATER`.
Insert AES-GCM ciphers right after AES-CTR ciphers but before AES-CBC ciphers, which is similar with OpenSSH:
```
debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
```
Although Dictionary's order is not defined, from observation, it is in the same order with add. Anyway that would be another topic.
* Suppress CA1859 "Use concrete types when possible for improved performance" for `ConnectionInfo.Encryptions`.
Test `Aes128Gcm` and `Aes256Gcm` only when `NET6_0_OR_GREATER`
* Update xml doc comments. Do not treat AesGcmCipher separately in Session.cs
* Fix build
* Fix build
* Update the comment as ChaCha20Poly1305 uses a separated key to encypt the packet length and the size it 4.
* Update src/Renci.SshNet/Security/Cryptography/Cipher.cs
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Make `AesGcmCipher` internal.
Assert offset when decrypt.
* Fix nullable error in build
* typos
---------
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Integrate `ZLibStream` from .NET 6.0+ with SSH.NET.
* OpenSSH server does not support zlib (pre-auth); OpenSSH client still supports zlib (pre-auth)
* Correct compression algorithm name; Update README.md
* Integrate `ZLibStream` from .NET 6.0+ with SSH.NET.
* OpenSSH server does not support zlib (pre-auth); OpenSSH client still supports zlib (pre-auth)
* Correct compression algorithm name; Update README.md
* Test the compression by upload/download file
* Refactor compression.
* Move delayed compression logic to base class.
* seal Zlib
* update unit test
* update unit test to see if it can trigger integration test
* Flush zlibStream
* Fix integration test
* update test
* Update ConnectionInfo.cs
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
* Update README.md
---------
Co-authored-by: Rob Hague <rob.hague00@gmail.com>
