To prevent users from being able to directly connect to registered
OpenSSH (Agentless) nodes, the OpenSSH CA was introduced. When
connecting to Agentless nodes, the Proxy will forward the connection
so the session can be recorded. The forwarding SSH server is configured
to authenticate to the target node with a certificate signed by OpenSSH
CA, which users do not have access to.
* Allow node to handle old and new way of client IP propagation on same listener
With addition of signed PROXY headers, node was listening on multiplexer, but because
of that it couldn't processing incoming connection from older proxies
when ProxyHelloSignature was used, because
both ends were waiting for the other side to send data first.
Here we integrate ability to handle PROXY headers into connection itself,
so we can start ssh server without waiting for multiplexer to detect connection
* Remove unneeded code
* Improve comment's wording
Co-authored-by: Michael Wilson <mike@mdwn.dev>
* Improve comment's wording
Co-authored-by: Michael Wilson <mike@mdwn.dev>
* Fix imports
* Unexport function
* Add godoc
* Remove unneeded comment
* Move ProxyHelloSignature to constants
* Check that proxyline is verified
* Use Warn() instead of Warnf()
* Move ProxyHelloSignature to api/constants
* Add timeout for getting host CA during proxyline verification.
* Rearrange conditions
Co-authored-by: Edoardo Spadolini <edoardo.spadolini@goteleport.com>
* Clarify comment.
---------
Co-authored-by: Michael Wilson <mike@mdwn.dev>
Co-authored-by: Edoardo Spadolini <edoardo.spadolini@goteleport.com>
* SCP -Change file attrs only when requested
OpenSSH sets 0644 by default and allows copy the source permissions by passing `-p` flag.
Our current implementation sets the file permissions even when client didn't use `-p` flag which can fail if the user doesn't have permissions to set it. This patch matches the OpenSSH behavior.
* Fix formatting
* sshserver: Correctly handle PuTTY winadj channel requests
Fixes#19365
* Actually send a failure
* dispatch changes
* Reimplement wantReply handling
* Also handle windadj in forwarding server
* lint: Fix typo
* lint: Invert return order to put err last
* Use nil return payload instead
* Use trace.ReplyAlreadyHandled instead
* Handle reply internally and set req.WantReply to false
* Use t.Cleanup()
* behaviour is not a misspelling but whatever makes you happy
* Suggestions from code review
* use 'path.Join' instead of 'filepath.Join' to build remote file paths
tsh on Windows when using 'filepath.Join' would create paths with forward
slashes in them, which non-Windows Nodes couldn't handle. Consistently use
'path.Join' to avoid issues.
Fixes#18919
* add comment explaining why 'path.Join' is used
* move comment to make linter happy
* Our current SFTP implementation uses a single channel to transfer data. Connections with a high latency cause very slow transfer. github.com/pkg/sftp allows transferring data using concurrent streams, which seems to solve the problem. In order to utilize the feature, the remote file must implement the WriteTo() or ReadFrom() and Stat() methods. I've moved the progress bar to relay the data from a local file, as we can still call Read() or Write() on it to update the progress.
This PR doesn't address the high CPU usage by github.com/pkg/sftp on low latency links.
Closes#20579
* Cleanup
* Fix fileTransferProgress
* Simplify interfaces
* Move helper to utils package
Add comments
* Added comments
* Change canceler implementation to return correct values from Read/Write
* Fix infinite recursive call in cancelWriter.
Introduces `limiter.Listener` to provide a consistent and reusable
mechanism for limiting incoming connections per client. The new
listener is used by `sshutils/server.go` instead of manually applying
limits in `HandleConnection`.
This is particularly important now that the Proxy SSH port multiplexes
both SSH and gRPC. Each listener is now wrapped in a `limiter.Listener`
that uses the same `limiter.ConnectionsListener` to ensure that the
connection limits for the Proxy are enforced for all traffic on the
port.
- Add a generalized client store made up of a key, profile, and trusted certs store. Each sub store can support different backends (~/.tsh, identity_file, in-memory).
- Replace custom identity file handling with in-memory client store.
- Fix issues with trusted certs handling.
* Enable nolintlint linter
* Fix nolint comments in the api package
* Fix RDP client comment
* Address review comment
Co-authored-by: Alan Parra <alan.parra@goteleport.com>
* Allow unused for nolintlint linter
* Remove redundant casting
* Add comment on why allowed unused is enabled
Co-authored-by: Alan Parra <alan.parra@goteleport.com>
Co-authored-by: Alan Parra <alan.parra@goteleport.com>
Our need for customizing our security response headers primarily exists with the Content-Security-Policy. Other headers can be applied more broadly to provide safe defaults across our service.
This commit changes httpheaders.go to allow for the CSP to be applied separate from the other headers. Then the changes to httplib.go's handlers help make sure these headers are set generally (which we were already partially doing for caching directives).
Other changes were primarily making sure these tools are configured or used. Or a removal of previous settings as this function is now being handled more centrally.
Many of our tests (db package, I'm looking at you) generate many RSA keys. This has two main side effects; makes our tests slow and flaky as CPU usage spikes in random moments when the tests are run in parallel.
This change pre-generates RSA keys at the beginning of each test module and reuse them in randomized order to reduce the situation that one key has been used multiple times in one test.
I had to move a few files to avoid circular dependencies.
* Ensure ssh connection rejection errors are returned
#18302 altered the connection flow which changed the communication
via ssh. Prior to the change an ssh channel was opened first, then
global requests were sent. After the change a global request is sent
prior to opening a channel. This caused users to no longer receive a
human readable rejection message a la: `ssh: rejected: administratively
prohibited (too many concurrent ssh connections for user`, instead only
an `EOF` was returned.
To ensure that the correct message is provided to users two changes are
made, although only the client side change is strictly required.
1) the tracing ssh client now returns any rejected errors cached from
opening the tracing channel
2) the ssh server now processes global requests during it's wait period
waiting for a channel to reject and send the replies to any requests
with said rejection
`TestLockInForce` was updated to include attempting to send a global
request so both scenarios are covered as order should not matter.
This change introduces a workaround for OpenSSH 7.x bug related to SHA-2 signed certificates. Teleport signs all certificates with SHA-2-512, which prevents us from connecting to older sshd. As a workaround, we will send the same certificate signed with SHA-2-512 (as we do right now) and SHA-1 if the first authentication fails. We always send the SHA-2 certificates first, so newer OpenSSH versions should always use SHA-2 certs as they do right now.
* switch underlying protocol used for 'tsh scp' to SFTP
* address TODO
* appease linter
* add method to make it easier for other callers to transfer files
* add tests
* print transfer progress with progress bar by default
Also allow a SIGINT to gracefully stop the SFTP connection. This is
necessary because the progress bar will ignore signals and prevent the
process from exiting.
* address SFTP fork issues
* make tests less flakey
* fix specifying dir for dst not copying files to correct paths
* make tests less flakey (again)
* don't check file access times, often differs when run in CI
* few small fixes from review, simplify Create method now that HTTP FS isn't needed
* create dst files and dirs with src mode
* improved error messages when doing file operations
* expand home dirs in remote paths
* addressed more feedback
* add license to get_home_dir.go
* address minor feedback of tests, add home dir expansion test
* update sftp fork to point to latest commit on master branch
* addressed feedback
* don't cache home dir lookups, only one remote path can ever be used
* Allow tsh to retrieve cluster details in one request
Prior to connecting to a node via `tsh ssh` we need two bits of
information about the cluster:
1) The session recording mode
2) Whether FIPS is enabled
In order to retrieve the information `tsh` first would send the
global ssh request `RecordingProxyReqType` to determine the
session recording mode. Later on `tsh` would Ping the auth
server to determine if the cluster was running in FIPS mode.
In an effort to reduce the number of round trips to retrieve
this data, a new global ssh request `ClusterDetailsReqType` is
introduced that returns both the session recording mode and
whether FIPS is enabled. This allows `tsh` to leverage the new
request to get all the information it needs, and is extensible
in case more information is needed` in one request which helps
reduce latency for `tsh ssh`.
Update metalinter, fix a few lint warnings and replace deprecated linters.
`deadcode`, `structcheck` and `varcheck` are abandoned and now replaced by [`unused`][1].
Since 1.19, `go fmt` reformats godocs according to https://go.dev/doc/comment. I've done a bulk-reformatting of the codebase to keep the linter happy. Backporting is mostly harmless (the exception being `lib/services/role_test.go`, that for some reason breaks the _old_ linter using the new format).
[1]: https://golangci-lint.run/usage/linters/
* Bump golangci-lint version
* Replace abandoned linters
* Fix bodyclose on lib/auth/github.com
* Fix bodyclose on lib/kube/proxy/streamproto/proto_test.go
* Fix bodyclose on lib/srv/alpnproxy/proxy_test.go
* Fix bodyclose on lib/web/conn_upgrade_test.go
* Silence staticcheck on lib/kube/proxy/forwarder_test.go
* Silence staticcheck on lib/utils/certs_test.go
* Address BuildNameToCertificate deprecation warnings
* Run `go fmt ./...`
* Run `go fmt ./...` on api/
* Ignore formatting in role_test.go
* Remove redundant initializers in lib/srv/uacc/
* Update e/
* Prevent ssh.Session SendRequest from wrapping payload twice
Payloads were inadvertently being wrapped twice by sessions making
the ssh server unable to parse the request payload. This is largely
only an issue for window-change requests, as they are the only request
being sent directly via a session that contains a payload. All window-change
requests now use ssh.Session WindowChange instead or sending the request
manually.
Adds a wrapper around `ssh.Session` which injects tracing context
in a similar manner to the `ssh.Client` wrapper. All usages of
`ssh.Session` have now been replaced and have the appropriate
`context.Context` passed along
Part of #12241
* Add additional debug logging for instantiation of ssh server conn
* Rough out introducing mux to ssh listener
* Catch errors from multiplexer serve
* Adapt multiplexer to support ProxyHelloSignature
* Adjust logging for ssh conn creation
* Adjust tests to use semantically correct assert/require helpers
* Address PR comments
* Check Client addr is properly propagated in mux test
* SSH request tracing
Add tracing support for ssh global requests and channels. Wrappers
for `ssh.Client`, `ssh.Channel`, and `ssh.NewChannel` provide a
mechanism for tracing context to be propagated via a `context.Context`.
In order to maintain backwards compatibility the ssh.Client wrapper
tries to open a TracingChannel when constructed. Any servers that
don't support tracing will reject the unknown channel. The client
will only provide tracing context to servers which do NOT reject
the TracingChannel request.
In order to include pass tracing context along all ssh payloads
are wrapped in an Envelope that includes the original payload
AND any tracing context. Servers now try to unmarshal all payloads
into said Envelope when processing messages. If there is an Envelope
provided, a new span will be created and the original payload will
be pass along to handlers.
Part of #12241
* configure golangci-lint misspell to check for anglicized spellings
* Americanize spellings
* fix aws constant value with british spelling 🇬🇧
* update api types with americanized spellings
* use american spellings .cloudbuild/scripts
* Update api/types/fuzz_test.go
* do not fail if the file is missing
* missing go-118-fuzz-build fix
Co-authored-by: Zac Bergquist <zac.bergquist@goteleport.com>
This change adds IP-based validation for SSH certificates.
There's new option in role definition:
kind: role
metadata:
name: dev
spec:
options:
pin_source_ip: true
When that is set to true client IP must be the same when generating certificates and using them. It uses source_address critical option that should be supported by both teleport and sshd and only applies to certificates we send to user (like in tsh login), we don't pin IP in certificates issued for web UI as they can't leak.
This change also omits machine ID (it uses different code path) - it will be added in separate PR.
Most of the lines changed are from regenerating types.proto, change itself is not that big
Relates #11719
After the merge of https://github.com/gravitational/teleport/pull/12674 we no longer use the following configuration:
```yaml
teleport:
ca_signature_algo: "rsa-sha2-512"
```
As we now rely upon the `x/crypto` package to choose the signing algorithm (it defaults to `rsa-sha2-512`)
**Demo**
If we set `ca_signature_algo` (the value is irrelevant) and start `teleport` we get:
```shell
root@marco:/workspace# teleport start --debug
2022-06-02T09:33:58Z WARN ca_signing_algo config option is deprecated and will be ignored, we'll always default to rsa-sha2-512. config/configuration.go:348
2022-06-02T09:33:58Z INFO Generating new host UUID: b001159a-10e0-49a7-b4dc-61c73fbe9e42. service/service.go:726
...
```
Fixes#12905
This adds proxy peering support. A configurable setting that allows for agents
to connect to a subset of proxies and be reachable through any proxy in the
cluster. This is achieved by creating grpc connections between each proxy
server. Client connections can then be passed between proxies to the desired
agent.
This commit upgrades the version of x/crypto we use, to the current latest
`go get -u golang.org/x/crypto`
We also replaced the deprecated variables and updated the tests to match the
current default KEX Algos
The x/crypto didn't support RSA-SHA2 algos, so we developed our own algorithm
signer. This is no longer the case, and after upgrading x/crypto to 20220518 we
can safely remove the custom code we have.
From OpenSSH 8.8+, it works if we explicitly add the older algorithm
Somthing like this: `./ssh -vvv -oPubkeyAcceptedAlgorithms=+ssh-rsa-cert-v01@openssh.comteleportadmin@moon.marco.mydemo`
* Add tracing instrumentation for ssh clients/servers
Add tracing context to the existing ProxyHelloSignature to provide
span information across ssh connections. To add span context per
ssh session on top of new connections, the same tracing context is
passed in the first global request of the session.
In order to ensure that tracing context is pulled from and inserted
into the proper context.Context, some interfaces and methods were
changed to take one as the first argument.
When proxying connections, PuTTY automatically requests the 'simple@putty.projects.tartarus.org' channel
type to indicate that this is a "simple" connection which will not be requesting other channel formats.
A request to Teleport for this channel currently results in the connection being terminated. A better
idea is just to ignore this request.
* Remove unused backend wrapper from Cache
* Remove double printShutdownStatus
* Fix readyz race condition
* Test coverage for the readyz.monitor fix
* Close listeners immediately in proxy.shutdown
* Use and handle net.ErrClosed correctly
This adapts utils.IsUseOfClosedNetworkError to check for net.ErrClosed
even inside trace.Aggregate errors, makes it so that we always return
something that would pass errors.Is(err, net.ErrClosed) when returning
from a (net.Listener).Accept(), and handles closed listeners within our
various Serve() loops so that we don't hit spurious backoff waits while
shutting down.
* Close listeners early and emitters late
* Test coverage for the proxy listener changes
* Revert some errors back to trace.ConnectionProblem
* Reduce PR scope to just the proxy, add comments
* Improve error logging.
Andrew LeFevre