libgit2: fix ssh host key verification regression #771
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
aryan9600
force-pushed
the
fix-hostcallback
branch
from
3fb7441 to
198a461
Compare
aryan9600
changed the title
Earlier, host key verification could potentially fail if there were multiple entries in the known_hosts file and if the intended encryption algorithm wasn't the first entry. This happened because we used the same hasher object to compute the sum of all the public keys present in the known_hosts file, which led to invalid hashes, resulting in a mismatch when compared with the hash of the advertised public key. This is fixed, by not creating the hasher ourselves and instead delegating that to the function actually doing the matching, ensuring that a new hasher is used for each comparison. Regression introduced in v0.25.0 and reported in fluxcd/image-automation-controller#378 Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
aryan9600
force-pushed
the
fix-hostcallback
branch
from
198a461 to
4769253
Compare
pjbgf
approved these changes
Jun 8, 2022
Comment on lines
+14
to
+17
| var knownHostsFixture = `github.com ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAq2A7hRGmdnm9tUDbO9IDSwBK6TbQa+PXYPCPy6rbTrTtw7PHkccKrpp0yVhp5HdEIcKr6pLlVDBfOLX9QUsyCOV0wzfjIJNlGEYsdlLJizHhbn2mUjvSAHQqZETYP81eFzLQNnPHt4EVVUh7VfDESU84KezmD5QlWpXLmvU31/yMf+Se8xhHTvKSCZIFImWwoG6mbUoWf9nzpIoaSjB+weqqUUmpaaasXVal72J+UX2B+2RPW3RcT0eOzQgqlJL3RKrTJvdsjE3JEAvGq3lGHSZXy28G3skua2SmVi/w4yCE6gbODqnTWlg7+wC604ydGXA8VJiS5ap43JXiUFFAaQ== | ||
| github.com ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBEmKSENjQEezOmxkZMy7opKgwFB9nkt5YRrYMjNuG5N87uRgg6CLrbo5wAdT/y6v0mKV0U2w0WZ2YB/++Tpockg= | ||
| github.com ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIOMqqnkVzrm0SdG6UOoqKLsabgH5C9okWi0dh2l9GKJl | ||
| ` |
There was a problem hiding this comment.
This could fail to simulate the scenario based on external factors that may change in the future. This is OK for now, but we should consider depending on a test server when refactoring/consolidating the Git implementation.
# for free
to join this conversation on GitHub.
Already have an account?
# to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Earlier, host key verification could potentially fail if there were
multiple entries in the known_hosts file and if the intended encryption
algorithm wasn't the first entry. This happened because we used the same
hasher object to compute the sum of all the public keys present in the
known_hosts file, which led to invalid hashes, resulting in a mismatch
when compared with the hash of the advertised public key. This is fixed,
by not creating the hasher ourselves and instead delegating that to the
function actually doing the matching, ensuring that a new hasher is used
for each comparison.
Regression introduced in v0.25.0 and reported in
fluxcd/image-automation-controller#378
Signed-off-by: Sanskar Jaiswal jaiswalsanskar078@gmail.com