- Don't assume an explicit $GOPATH is set
- Remove golint from linters - it's been deprecated for over a year
and golangci-lint prints a warning instead of running it.
Updated how BPF assets are embedded. Missing object files will now be a
runtime error instead of a build time error. However, this will allow
teleport/lib to used as a module because tools like "go mod vendor" were
failing when attempting to vendor teleport/lib due to the missing object
files.
Added bytecode directory with README.md so "go:embed" does not complain
about missing assets. This allow developers to checkout Teleport and
work on it without needing libbpf or any other BPF tooling.
Adds the ability to block network traffic on SSH sessions.
The deny/allow lists of IPs are specified in teleport.yaml file.
Supports both IPv4 and IPv6 communication.
This feature currently relies on enhanced recording for
cgroup management so that needs to be enabled as well.
-- Design rationale:
This patch uses Linux Security Module (LSM) hooks, specifically
security_socket_connect and security_socket_sendmsg, to control
egress traffic. The LSM provides two advantages over socket filtering
program types.
- It's executed early enough that the task information is available.
This makes it easy to report PID, COMM, etc.
- It becomes a model for extending restrictions beyond networking.
The set of enforced cgroups is stored in a BPF hash map and the
deny/allow lists are stored in BPF trie maps. An IP address is
first checked against the allow list. If found, it's checked for
an override in the deny list. The policy is default deny. However,
the absence of the NetworkRestrictions API object is allow all.
IPv4 addresses are additionally registered in IPv6 trie (as mapped)
to account for dual stacks. However it is unclear if this is sufficient
as 4-to-6 transition methods utilize a multitude of translation and
tunneling methods.
If the page size for an enhanced event is 0, then don't attempt to load
that BPF program. This is helpful for BPF programs that generate massive
amounts of events (like disk events).
Added package cgroup to orchestrate cgroups. Only support for cgroup2
was added to utilize because cgroup2 cgroups have unique IDs that can be
used correlated with BPF events.
Added bpf package that contains three BPF programs: execsnoop,
opensnoop, and tcpconnect. The bpf package starts and stops these
programs as well correlating their output with Teleport sessions
and emitting them to the audit log.
Added support for Teleport to re-exec itself before launching a shell.
This allows Teleport to start a child process, capture it's PID, place
the PID in a cgroup, and then continue to process. Once the process is
continued it can be tracked by it's cgroup ID.
Reduced the total number of connections to a host so Teleport does not
quickly exhaust all file descriptors. Exhausting all file descriptors
happens very quickly when disk events are emitted to the audit log which
are emitted at a very high rate.
Added tarballs for exec sessions. Updated session.start and session.end
events with additional metadata. Updated the format of session tarballs
to include enhanced events.
Added file configuration for enhanced session recording. Added code to
startup enhanced session recording and pass package to SSH nodes.