Fix SSH state machine for ssh-agent authentication #2248
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In case an identity didn't match[0], the state machine would fail in state SSH_AUTH_AGENT instead of progressing to the next identity in ssh-agent. As a result, ssh-agent authentication only worked if the identity required happened to be the first added to ssh-agent. This was introduced as part of commit c4eb10e, which stated that the "else" statement was required to prevent getting stuck in state SSH_AUTH_AGENT. Given the state machine's logic and libssh2's interface I couldn't see how this could happen or reproduce it and I also couldn't find a more detailed description of the problem which would explain a test case to reproduce the problem this was supposed to fix. [0] libssh2_agent_userauth returning LIBSSH2_ERROR_AUTHENTICATION_FAILED
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How to reproduce:
After applying the patch, 5. succeeds as expected. |
bagder
approved these changes
Jan 18, 2018
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Thanks! |
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In case an identity didn't match[0], the state machine would fail in
state SSH_AUTH_AGENT instead of progressing to the next identity in
ssh-agent. As a result, ssh-agent authentication only worked if the
identity required happened to be the first added to ssh-agent.
This was introduced as part of commit c4eb10e,
which stated that the "else" statement was required to prevent getting stuck
in state SSH_AUTH_AGENT. Given the state machine's logic and libssh2's
interface I couldn't see how this could happen or reproduce it and
I also couldn't find a more detailed description of the problem which
would explain a test case to reproduce the problem this was supposed to fix.
[0] libssh2_agent_userauth returning LIBSSH2_ERROR_AUTHENTICATION_FAILED