Fix agent forwarding for multi-session connections #3613
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retest this please |
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retest this please |
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| c.RLock() | ||
| defer c.RUnlock() | ||
| return c.agent | ||
| if c.Parent == nil { |
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Should GetAgent and GetAgentChannel return an error? Because it could potentially segfault here.
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The fact that agent might be nil seems to be well handled, so I've opted to update the method docs to indicate that it might be nil rather than changing the method to return an error.
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@awly Can you take a look as well? |
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| @@ -1265,11 +1265,11 @@ func (s *discardServer) Stop() { | |||
| s.sshServer.Close() | |||
| } | |||
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| func (s *discardServer) HandleNewChan(conn net.Conn, sconn *ssh.ServerConn, newChannel ssh.NewChannel) { | |||
| func (s *discardServer) HandleNewChan(ccx *sshutils.ConnectionContext, newChannel ssh.NewChannel) { | |||
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I deliberately assumed the convention of referring to sshutils.ConnectionContext as ccx to handle the fact that it is frequently in-scope at the same time as srv.ServerContext, which is already conventionally called ctx.
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| if c.Parent == nil { | ||
| return nil | ||
| } |
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Shouldn't c.Parent always be set?
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Removed nil checks for methods which modify state. All the getters on the zero value of srv.ConnectionContext return zero values themselves instead of panicking (a fact that some tests rely on), so I kept the nil checks on the getters in order to preserve this behavior.
| // make sure the socket is gone after we closed the connection. | ||
| err = s.clt.Close() | ||
| c.Assert(err, IsNil) | ||
| s.clt = nil |
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nullifying clt prevents test-failure due to double-close in the suite's cleanup function. Added comment to clarify.
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| // ConnectionContext manages connection-level state. | ||
| type ConnectionContext struct { |
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Context is overloaded in Go.
How about just ServerConn or Conn?
Changes the lifetime of agent forwarding to be scoped to the underlying ssh connection, instead of the specific ssh channel which initially passed the agent forwarding request.
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Changes agent channel setup behavior to be consistent openssh by having servers lazily request agent channels when they are needed, rather than immediately starting a single connection-wide channel as soon as forwarding is requested. Fixes an issue introduced in #3613 which caused openssh clients to hang on exit due to persistent agent channel.
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May 28, 2020
Changes agent channel setup behavior to be consistent openssh by having servers lazily request agent channels when they are needed, rather than immediately starting a single connection-wide channel as soon as forwarding is requested. Fixes an issue introduced in #3613 which caused openssh clients to hang on exit due to persistent agent channel.
fspmarshall
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Jun 6, 2020
Changes agent channel setup behavior to be consistent openssh by having servers lazily request agent channels when they are needed, rather than immediately starting a single connection-wide channel as soon as forwarding is requested. Fixes an issue introduced in #3613 which caused openssh clients to hang on exit due to persistent agent channel.
fspmarshall
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Jun 10, 2020
Changes agent channel setup behavior to be consistent openssh by having servers lazily request agent channels when they are needed, rather than immediately starting a single connection-wide channel as soon as forwarding is requested. Fixes an issue introduced in #3613 which caused openssh clients to hang on exit due to persistent agent channel.
fspmarshall
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Jun 10, 2020
Changes agent channel setup behavior to be consistent openssh by having servers lazily request agent channels when they are needed, rather than immediately starting a single connection-wide channel as soon as forwarding is requested. Fixes an issue introduced in #3613 which caused openssh clients to hang on exit due to persistent agent channel.
fspmarshall
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Jun 22, 2020
Changes agent channel setup behavior to be consistent openssh by having servers lazily request agent channels when they are needed, rather than immediately starting a single connection-wide channel as soon as forwarding is requested. Fixes an issue introduced in #3613 which caused openssh clients to hang on exit due to persistent agent channel.
fspmarshall
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Jun 24, 2020
Changes agent channel setup behavior to be consistent openssh by having servers lazily request agent channels when they are needed, rather than immediately starting a single connection-wide channel as soon as forwarding is requested. Fixes an issue introduced in #3613 which caused openssh clients to hang on exit due to persistent agent channel.
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This PR changes the lifetime of agent forwarding to be scoped to the underlying ssh connection, instead of the specific ssh channel which initially passed the agent forwarding request.
Previous behavior was inconsistent with how openssh handles agent forwarding, and was causing issues with applications which rely on creating multiple separate
execsessions on a single connection.Fixes #3471