Dropping Privileges in Go
2 days ago
- #Go programming
- #security
- #privilege dropping
- Computer programs inherit user privileges, which can lead to unintended access to resources like private keys if exploited.
- The principle of least privilege advocates restricting software to only necessary privileges to mitigate damage from exploits.
- Software can self-restrict by dropping privileges early, such as after acquiring needed resources like network ports.
- Classic POSIX methods include chroot to change root directory and setresuid/setresgid to switch to unprivileged users.
- setrlimit can limit resources like CPU time and memory to prevent abuse (e.g., via RLIMIT_CPU and RLIMIT_DATA).
- OpenBSD offers pledge to restrict syscalls and unveil to allow-list file system paths, enhancing security simply.
- Linux provides Seccomp BPF for syscall filtering and Landlock for file system and network access restrictions.
- Go libraries like syscallset-go and go-landlock simplify implementing these restrictions in Go programs.
- Developers should integrate these mechanisms to reduce attack surfaces, as vulnerabilities are often a matter of time.
- Examples and code are available in a repository for practical implementation.