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SimpleeBPF-based exec snooping on Linux packaged as a Golibrary.

exectrace loads a pre-compiledeBPF program into the runningkernel to receive details about theexec family of syscalls.

exectrace provides workspace process logging for Coder v1 andCoder v2 (aka. Coder OSS).

Documentation for how to setup workspace process logging for Coder v1 users canbe foundhere.

Documentation for Coder v2 users can be found inenterprise/README.md.

exectrace only supports Go 1.16+ and Linux kernel 5.8+ (due to the use ofBPF_MAP_TYPE_RINGBUF). Additionally, the kernel configCONFIG_DEBUG_INFO_BTF=y is required.

To validate this config is enabled, run either of the following commandsdirectly on the system:

$cat /proc/config.gz| gunzip| grep CONFIG_DEBUG_INFO_BTF

$cat"/boot/config-$(uname -r)"| grep CONFIG_DEBUG_INFO_BTF

$go get -u github.com/coder/exectrace

You will need root access,CAP_SYS_ADMIN orCAP_BPF, to run eBPF programs onyour system.

Usego run -exec sudo ./cmd/program to compile a program and start it withsudo

$go install -u github.com/coder/exectrace/cmd/exectrace$exectrace --help...$sudo exectrace2021/12/01 16:42:02 Waiting for events..[1188921, comm="node", uid=1002, gid=1003, filename=/bin/sh] /bin/sh -c 'which ps'[1188922, comm="sh", uid=1002, gid=1003, filename=/usr/bin/which] which ps

exectrace exposes a minimal API surface. Callexectrace.New(nil) and then youcan start reading events from the returnedTracer.

It is important that you close the tracer to avoid leaking kernel resources, sowe recommend implementing a simple signal handler like the one in this example:

package mainimport ("fmt""os""os/signal""syscall""github.com/coder/exectrace")funcmain() {tracer,err:=exectrace.New(nil)iferr!=nil {panic(err)}defertracer.Close()gofunc() {sigs:=make(chan os.Signal,1)signal.Notify(sigs,syscall.SIGINT,syscall.SIGTERM)<-sigstracer.Close()}()for {event,err:=tracer.Read()iferr!=nil {panic(err)}fmt.Printf("%+v\n",event)}}

For a full usage example, refer to thiscomprehensive program that uses the library.

You will need the following:

• Docker (the Makefile runs clang within a Docker container for reproducibility)
• Golang 1.20+
• golangci-lint
• prettier
• shellcheck

Since the eBPF program is packaged usinggo:embed, you will need to compilethe program and include it in the repo.

If you change the files in thebpf directory, runmake and ensure that youinclude the.o files you changed in your commit (CI will verify that you'vedone this correctly).

This library is ready to use as-is. It has been used in production for years andhas received minimal maintenance over that time period.

In April 2024, a system to send logs from the kernel to userspace was addedwhich can make discovering potential issues in production/development mucheasier.

The API will likely not be further modified as we have no need for additionalfields/features. We will continue to maintain the library as needed.

• canonical/etrace - Go binary thatuses ptrace and tracks the processes that a command launches for debugging andanalysis
• shirou/gopsutil - Go library that hasmethods for listing process details and getting information about the system

Dual licensed under the MIT and GPL 2.0 licenses. SeeLICENSE.

Code in the enterprise directory has a different license. SeeLICENSE.enterprise.