Commit Graph

98 Commits

Author SHA1 Message Date
Sanskar Jaiswal 590aa325b0 libgit2: fix managed transport enabled flag updation
Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-06-10 18:12:58 +05:30
Sanskar Jaiswal 45ee564e27 assert state of managed transport acc for each test
Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-06-09 22:21:10 +05:30
Sanskar Jaiswal 4ce31319ee libgit2: refactor tests to use managed and unmanaged transport cleanly
Refactors libgit2 checkout tests to test managed and unmanaged
transport by making sure the tests requiring unmanaged transport are run
before, any tests that require managed transport (since disabling
managed transport isn't possible). This is done via arranging the tests
carefully in alphabetically sorted names, i.e. the tests with unmanaged
transport go in `checkout_test.go`, which forces golang to run the tests
in that file before any other tests.

Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-06-09 21:01:17 +05:30
Paulo Gomes bfa4e38b84
libgit2: dispose connections in SubTransport.Close
The average SubTransport lifecycle encompass two Actions calls. Previously,
it was attempted to share the same connection across both calls. That did
not work as some Git Servers do not support multiple sessions from the same
connection. The implementation was not fully transitioned into the
"one connection per action" model, which led to connection being leaked.

The transition to RW mutex was to avoid the unnecessary blocking in the
goroutine at the start of the second action call.

It is worth mentioning that now when the context is done,  the client level
resources (connection) will also be freed. This ensures that SSH connections
will not outlive the subtransport.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-06-08 19:39:50 +01:00
Paulo Gomes 23b337f6be
libgit2: Improve HTTP redirection observability
Git repositories may be redirected to different URLs
when they are accessed via HTTP. The two most obvious
scenarios are from HTTP to HTTPS and when the .git suffix
is missing.
By improving the logging on this process users can identify
changes required to their GitRepository objects.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-06-08 09:46:28 +01:00
Sanskar Jaiswal 47692530d7 libgit2: fix ssh host key verification regression
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
https://github.com/fluxcd/image-automation-controller/issues/378

Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-06-08 13:59:32 +05:30
Paulo Gomes b764bdbeaa
libgit2: fix gitlab redirection for HTTP
Gitlab only supports HTTP redirection for GET operations,
and fails POST operations targeting a repository without
the .git suffix.

Fixes: https://github.com/fluxcd/image-automation-controller/issues/379
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-06-07 15:11:16 +01:00
Sanskar Jaiswal c341ac3364 libgit2: return CheckoutTag with LastRevision
Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-06-03 14:00:23 +05:30
Sunny 7f7490ebf0
libgit2/managed: fix race issues in ssh transport
Race conditions in ssh smart subtransport caused some goroutines to
panic, resulting in crashing the whole controller, mostly evident in
image-automation-controller CI runs. Panic recovery in the main thread
do not handle goroutine panics. So, the existing panic recovery code in
libgit2 Checkout() methods weren't able to handle it.

This change groups the fields in ssh smart subtransport that may be
accessed by multiple goroutines into a new struct with a mutex. Also
adds panic recovery in the created goroutine to handle any other
possible panics.

Signed-off-by: Sunny <darkowlzz@protonmail.com>
2022-06-03 01:45:18 +05:30
Sanskar Jaiswal ae27f9ec69 libgit2: fix checkout logic for CheckoutBranch
Use the target commit, to checkout tree and set the head to the desired
branch instead of doing a hard reset to the target commit.

Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-06-01 14:14:28 +05:30
Sunny 86610667b1
libgit2: Enable tests
TestMain() without m.Run() resulted in none of the tests being run.

This libgit2 package contains tests for both managed and unmanaged
transports, enabling it in TestMain() for everything results in the
unmanaged transport tests to not run. Add managed transport
initialization call to all the managed transport tests to allow
unmanaged transport tests to run.

Signed-off-by: Sunny <darkowlzz@protonmail.com>
2022-05-29 15:28:08 +05:30
Sunny e0883ffb20
libgit2: Pass ctx to all the transport opts
The context passed to Checkout() has a timeout. Pass it forward to
the transport in the option for all the checkouts.

Signed-off-by: Sunny <darkowlzz@protonmail.com>
2022-05-28 22:14:21 +05:30
Paulo Gomes 978148ea71
libgit2: enforce context timeout
Some scenarios could lead a goroutine to be running indefinetely within managed ssh.
Previously between the two git operations, the reconciliation
could take twice the timeout set for the Flux object.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-27 13:59:50 +01:00
Sanskar Jaiswal 972d1cac2a fix docs, error handling and managed proxy auth
Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-05-27 14:01:23 +05:30
Sanskar Jaiswal ec45a612b1 enable managed transport for controller tests
Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-05-27 14:01:23 +05:30
Sanskar Jaiswal 5152721ae0 factor out unmanaged checkout into its own functions
Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-05-27 14:01:23 +05:30
Sanskar Jaiswal 94c50fa3a8 remvoe support for sha1 and md5 hashing for public keys
Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-05-27 14:01:23 +05:30
Sanskar Jaiswal 7d2bc64f47 fix panics on unmanaged http and proxy on managed http
Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-05-27 14:01:23 +05:30
Sanskar Jaiswal d4beacb6ad Remove dependency on libgit2 credentials callback
Injects transport and auth options at the transport level directly to
bypass the inbuilt credentials callback because of it's several
shortcomings. Moves some of the pre-existing logic from the reconciler
to the checkout implementation.

Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-05-27 14:01:23 +05:30
Paulo Gomes a0d0a6312d
libgit2: enable managed transport by default
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-24 10:46:32 +01:00
Sunny 749068e9c3
pkg/git: introduce concrete and partial commit
Introduce concrete and partial commits. Concrete commits have all the
information from remote including the hash and commit content. Partial
commits are based on locally available copy of a repo, they may only
contain the commit hash and reference.

IsConcreteCommit() can be used to find out if a given commit is based on
local information or full remote repo information.

Update go-git and libgit2 branch/tag clone optimization to return a
partial commit and no error.

Update and simplify the go-git and libgit2 tests for the same.

Signed-off-by: Sunny <darkowlzz@protonmail.com>
2022-05-20 19:52:18 +05:30
Paulo Gomes 8b50367849
libgit2: Add support for hashed known_hosts
Hashed known_hosts was previously only supported when using
go-git. Now both Git implementations benefit from this
features, and the code coverage across them can ensure no
future regression.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-16 16:57:22 +01:00
Paulo Gomes 6a407704a3
libgit2: remove redundant test
Both libgit2 and go-git now have tests that confirms
support for the supported authentication algorithms.
This test was created previously and is no longer
needed.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-13 15:00:10 +01:00
Paulo Gomes ce92881013
libgit2: remove connection caching
Connection caching was a feature created to resolve
upstream issues raised from concurrent ssh connections.
Some scenarios were based on multiple key exchange
operations happening at the same time.

This PR removes the connection caching, and instead:
- Services Session.StdoutPipe() as soon as possible,
  as it is a known source of blocking SSH connections.
- Reuse SSH connection within the same subtransport,
  eliminating the need for new handshakes when talking
  with the same server.
- Simplifies the entire transport logic for better
  maintainability.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-13 11:09:02 +01:00
Paulo Gomes 90ef278797
libgit2: return func to help callers free git2go objects
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-11 13:02:27 +01:00
Paulo Gomes 44e166e576
libgit2: dispose git2go objects when error != nil
getBlankRepoAndRemote's callers are responsible for the disposal
of the returned objects. However, the caller does not expect to
need to dispose objects when err != nil, which may result to memory
leaks.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-11 11:40:09 +01:00
Paulo Gomes 54e07d8783
libgit2: recover from panic in short-circuited clones
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-11 11:40:08 +01:00
Sanskar Jaiswal 6a793a55f6
Optimize libgit2 checkout tag strategy through condition no-ops
Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-05-11 11:40:05 +01:00
Paulo Gomes 860d7051da
libgit2: optimise checkout branch clones
No-op reconciliations are very inefficient, as they carry out
a full clone operation of the target repository even when
no changes have taken place.

This change will execute a remote-ls operation, and cancel
the clone operation if the remote tip commit is still the same
as the one observed on the last reconcilation. In such cases,
an git.NoChangesError is returned.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-11 11:40:04 +01:00
Paulo Gomes 2b59150fbe
tests: algorithms test coverage for go-git and libgit2
Assures support for:
- Authentication Key Types
  - rsa
  - ecdsa P256
  - ecdsa P384
  - ecdsa P521
  - ed25519
- Key Exchange Algoritms:
  - diffie-hellman-group14-sha1
  - diffie-hellman-group14-sha256
  - curve25519-sha256
  - ecdh-sha2-nistp256
  - ecdh-sha2-nistp384
  - ecdh-sha2-nistp521
  - curve25519-sha256@libssh.org
- HostKey Algoritms:
  - ssh-rsa
  - rsa-sha2-256
  - rsa-sha2-512
  - ecdsa-sha2-nistp256
  - ecdsa-sha2-nistp384
  - ecdsa-sha2-nistp521
  - ssh-ed25519

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-09 13:31:54 +01:00
Paulo Gomes 4e3e62923b
git: Add git.HostKeyAlgos
Enables the setting of HostKey algorithms to be used from
a client perspective. This implementation supports go-git
and libgit2 when in ManagedTransport.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-06 17:58:09 +01:00
Paulo Gomes c0c5046e5f
libgit2: recover from git2go panic
Some specific scenarios may lead libgit2 or git2go to panic.
Adding a recovery logic, ensures a predictable execution path
for callers, and safeguards the controller's stability.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-05-06 08:39:00 +01:00
Eng Zer Jun 10b92da433
test: use `T.TempDir` to create temporary test directory
This commit replaces `os.MkdirTemp` with `t.TempDir` in tests. The
directory created by `t.TempDir` is automatically removed when the test
and all its subtests complete.

Prior to this commit, temporary directory created using `os.MkdirTemp`
needs to be removed manually by calling `os.RemoveAll`, which is omitted
in some tests. The error handling boilerplate e.g.
	defer func() {
		if err := os.RemoveAll(dir); err != nil {
			t.Fatal(err)
		}
	}
is also tedious, but `t.TempDir` handles this for us nicely.

Reference: https://pkg.go.dev/testing#T.TempDir
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
2022-04-29 23:01:39 +08:00
Paulo Gomes 68eece48fb
libgit2: optimise mutex on cached connections
Previously the mutex.Lock was acquired before creating
a new connection. The lock would then hold until the
process was finished, and all network latency would be
absorbed by other goroutines trying to establish a new
connection.

Now the lock is acquired after the connection has been
created. The downside of this approach is that concurrent
goroutine may be trying to open a connection to the same
target. The loser in the race will then have to Close the
connection and use the winner's instead.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-04-07 19:10:54 +01:00
Paulo Gomes b264a3513d
libgit2: refactor max length values into constants
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-04-07 19:10:50 +01:00
Paulo Gomes 3ab95a4bf0
libgit2: close discarded connections
Cached connections can be shared across concurrent
operations, and their disposal must take that into
account to avoid closing a connection that is stale for
one goroutine, but is still valid for another.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-04-07 18:37:40 +01:00
Paulo Gomes add07745f3
libgit2: restrict smart creds to Type SSH Memory
Avoid asking for SSH credential in files, as they won't be
used. The cacheKeyAndConfig func already enforces this
behaviour.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-04-07 18:37:39 +01:00
Paulo Gomes d86f0a280a
libgit2: validate URL max length
The major Git SaaS providers have repository URLs
for both HTTP and SSH that tops around 250
characters in length.

The limits chosen were a lot higher to align with use
cases in which users may have on-premise servers with
long domain names and paths.

For SSH the validation is around path length only,
which is now limited to 4096 characters, which is
at the higher end of the range in Linux.

For HTTP the validation is around the full URL
provided by the caller.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-04-07 18:37:38 +01:00
Paulo Gomes 54d0794d19
libgit2: handle the closing of stale connections
Internal and upstream calls to sshSmartSubtransport.Close()
when dealing with an stale connection, may lead to misleading
errors.

Focus should instead be redirected to ensuring that Close()
releases resources and ensures that a new SubTransport can be
created, so new operations can succeed.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-04-07 18:37:38 +01:00
Paulo Gomes 69c3f00172
libgit2: retry on stale connections
SSH servers that block the reuse of SSH connections for
multiple SSH sessions may lead to EOF when a new session
is being created.

This fixes the issue of long-running connections resulting
in EOF for GitLab servers.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-04-07 18:37:37 +01:00
Sanskar Jaiswal 5c84ea7e96 add flag to allow configuration of SSH kex algos
Adds a flag `ssh-kex-algos` which configures the gogit and libgit2
managed clients to use the specified list of kex algos for ssh. If not
used the default list in `golang/x/crypto/ssh` is used.

Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>
2022-04-07 16:43:15 +05:30
Paulo Gomes 36fcdeeb5e
libgit2: fix access to nil t.stdin and improve observability
All errors that were previously not handled are now logged through
traceLog, to further help during transport investigations.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-03-30 14:44:41 +01:00
Paulo Gomes 92ad1f813b
Cache SSH connections
The underlying SSH connections are kept open and are reused
across several SSH sessions. This is due to upstream issues in
which concurrent/parallel SSH connections may lead to instability.

https://github.com/golang/go/issues/51926
https://github.com/golang/go/issues/27140
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-03-28 11:58:10 +01:00
Paulo Gomes 017707a71c
Improve managed transport observability
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-03-25 19:08:54 +00:00
Paulo Gomes 5091b69ad5
Force ssh.Dial timeout
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-03-25 19:08:52 +00:00
Paulo Gomes a860ebee04
Reuse HTTP connections in managed transport
Ensure all requests are completely processed and closed,
to prove odds of the underlying connections to be reused.

The transport now is pooled and reused whenever possible.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-03-25 19:08:51 +00:00
Paulo Gomes 45641b17c7 Fix dpanic issue when logging odd number of args
Info was receiving odd number of arguments leading to:
odd number of arguments passed as key-value pairs for logging

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-03-25 14:27:04 +01:00
Paulo Gomes 115040e9ea
Support redirects for libgit2 managed transport
For backwards compatibility, support for HTTP redirection is enabled when targeting
the same host, and no TLS downgrade took place.

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-03-16 16:22:21 +05:30
Paulo Gomes 43661dd15e
Enforce effective URL on error messages
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-03-16 16:22:21 +05:30
Paulo Gomes d1a7e5d609
Fix race condition on httpSmartSubTransport
Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>
2022-03-16 16:22:21 +05:30