Files
agent-sandbox/src/sandbox.rs

142 lines
4.0 KiB
Rust

use std::path::Path;
use std::process::Command;
use crate::agents;
use crate::blacklist;
use crate::{SandboxConfig, SandboxError, SandboxMode};
pub fn build_command(config: &SandboxConfig) -> Result<Command, SandboxError> {
let mut cmd = Command::new("bwrap");
let hardened = config.hardened || matches!(config.mode, SandboxMode::Whitelist);
if hardened {
cmd.args(["--unshare-ipc", "--unshare-pid", "--unshare-uts"]);
cmd.args(["--hostname", "sandbox"]);
}
if config.no_net {
cmd.arg("--unshare-net");
}
match config.mode {
SandboxMode::Blacklist => add_blacklist_mode(&mut cmd)?,
SandboxMode::Whitelist => add_whitelist_mode(&mut cmd)?,
}
if matches!(config.mode, SandboxMode::Whitelist) {
cmd.args(["--tmpfs", "/tmp"]);
cmd.args(["--tmpfs", "/var/tmp"]);
cmd.args(["--dev", "/dev"]);
cmd.args(["--tmpfs", "/dev/shm"]);
cmd.args(["--tmpfs", "/run"]);
cmd.args(["--proc", "/proc"]);
}
for path in agents::agent_rw_paths() {
cmd.arg("--bind-try").arg(&path).arg(&path);
}
add_rw_bind(&mut cmd, &config.chdir)?;
for path in &config.extra_rw {
add_rw_bind(&mut cmd, path)?;
}
for path in &config.extra_ro {
add_ro_bind(&mut cmd, path)?;
}
cmd.arg("--die-with-parent");
cmd.arg("--chdir").arg(&config.chdir);
cmd.arg("--")
.arg(&config.command)
.args(&config.command_args);
Ok(cmd)
}
fn add_blacklist_mode(cmd: &mut Command) -> Result<(), SandboxError> {
let ctx = blacklist::resolve_path_context()?;
cmd.args(["--ro-bind", "/", "/"]);
let overlays = blacklist::resolve_overlays(&ctx)?;
for dir in &overlays.tmpfs_dirs {
cmd.arg("--tmpfs").arg(dir);
}
for file in &overlays.null_bind_files {
cmd.arg("--ro-bind").arg("/dev/null").arg(file);
}
cmd.args(["--dev-bind", "/dev", "/dev"]);
cmd.args(["--proc", "/proc"]);
cmd.args(["--bind", "/tmp", "/tmp"]);
cmd.args(["--bind", "/var/tmp", "/var/tmp"]);
cmd.args(["--bind", "/run", "/run"]);
Ok(())
}
fn add_whitelist_mode(cmd: &mut Command) -> Result<(), SandboxError> {
let home = std::env::var("HOME").map_err(|_| SandboxError::HomeNotSet)?;
cmd.args(["--ro-bind", "/usr", "/usr"]);
for path in ["/lib", "/lib64", "/lib32", "/bin", "/sbin"] {
cmd.args(["--ro-bind-try", path, path]);
}
for path in [
"/etc/ld.so.cache",
"/etc/ld.so.conf",
"/etc/ld.so.conf.d",
"/etc/alternatives",
] {
cmd.args(["--ro-bind-try", path, path]);
}
cmd.args(["--ro-bind-try", "/etc/ssl", "/etc/ssl"]);
cmd.args([
"--ro-bind-try",
"/etc/ca-certificates",
"/etc/ca-certificates",
]);
cmd.args(["--ro-bind-try", "/etc/resolv.conf", "/etc/resolv.conf"]);
cmd.args(["--ro-bind-try", "/etc/nsswitch.conf", "/etc/nsswitch.conf"]);
cmd.args(["--ro-bind-try", "/etc/passwd", "/etc/passwd"]);
cmd.args(["--ro-bind-try", "/etc/group", "/etc/group"]);
for path in [
"/etc/hosts",
"/etc/gai.conf",
"/etc/services",
"/etc/protocols",
] {
cmd.args(["--ro-bind-try", path, path]);
}
for path in ["/etc/hostname", "/etc/localtime", "/etc/machine-id"] {
cmd.args(["--ro-bind-try", path, path]);
}
let local_bin = format!("{home}/.local/bin");
cmd.arg("--ro-bind-try").arg(&local_bin).arg(&local_bin);
let cache_dir = format!("{home}/.cache");
cmd.arg("--tmpfs").arg(&cache_dir);
Ok(())
}
fn add_rw_bind(cmd: &mut Command, path: &Path) -> Result<(), SandboxError> {
if !path.exists() {
return Err(SandboxError::RwPathMissing(path.to_path_buf()));
}
cmd.arg("--bind").arg(path).arg(path);
Ok(())
}
fn add_ro_bind(cmd: &mut Command, path: &Path) -> Result<(), SandboxError> {
if !path.exists() {
return Err(SandboxError::RoPathMissing(path.to_path_buf()));
}
cmd.arg("--ro-bind").arg(path).arg(path);
Ok(())
}