[JENKINS-19429] SshSessionFactory.setInstance unnecessary

JGitAPIImpl. starts off by calling SshSessionFactory.setInstance(new TrileadSessionFactory()). This sets the VM-wide factory, which could be quite dangerous: it means that any other usage of JGit will not be using the standard logic in JschConfigSessionFactory to use ~/.ssh and so on.

Instead it should only set a TrileadSessionFactory directly using SshTransport.setSshSessionFactory when it calls Transport.open (and the result is an SshTransport). In some cases that is called directly; for PushCommand and similar uses that call Transport.open for you, it need only call TransportCommand.setTransportConfigCallback to configure an SshTransport with our authentication.

I can submit a pull request if you like—probably only JGitAPIImpl needs to be touched—though I am unsure how to test it. (I presume test_push does not push to a public server.)

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Originally reported by jglick, imported from: SshSessionFactory.setInstance unnecessary

• status: Open
  
• priority: Critical
  
• component(s): git-client-plugin
  
• resolution: Unresolved
  
• votes: 1
  
• watchers: 3
  
• imported: 20251211-071809
  

Raw content of original issue

JGitAPIImpl.<init> starts off by calling SshSessionFactory.setInstance(new TrileadSessionFactory()). This sets the VM-wide factory, which could be quite dangerous: it means that any other usage of JGit will not be using the standard logic in JschConfigSessionFactory to use ~/.ssh and so on.


Instead it should only set a TrileadSessionFactory directly using SshTransport.setSshSessionFactory when it calls Transport.open (and the result is an SshTransport). In some cases that is called directly; for PushCommand and similar uses that call Transport.open for you, it need only call TransportCommand.setTransportConfigCallback to configure an SshTransport with our authentication.


I can submit a pull request if you like—probably only JGitAPIImpl needs to be touched—though I am unsure how to test it. (I presume test_push does not push to a public server.)