diff --git a/README.md b/README.md index 9ed5419..4b53054 100644 --- a/README.md +++ b/README.md @@ -1,17 +1,16 @@ ### WHAT IS IT? -NsJail is a Linux process isolation tool making use of the namespacing features, and seccomp-bpf filters of the Linux kernel +NsJail is a Linux process isolation tool, making use of the the namespacing, resource control, and seccomp-bpf syscall filter subsystems of the Linux kernel This is NOT an official Google product. ### WHAT KIND OF ISOLATION DOES IT PROVIDE? -1. Linux namespaces: UTS, MOUNT, PID, IPC, NET, USER (optional) -2. FS chroot-ing: chroot(), pivot_root() -3. Resource limits (CPU time, etc.) +1. Linux namespaces: UTS, MOUNT, PID, IPC, NET, USER +2. FS constraints: chroot(), pivot_root(), RO-remounting +3. Resource limits (Wall-time/CPU time limits, VM space limits, etc.) 4. Seccomp-bpf syscall filters -### WHAT USE-CASES DOES IT COVER? -#### Isolating networking daemons (inetd-style) - +### WHICH USE-CASES ARE COVERED? +#### Isolation of network servers (inetd-style) + Server: ``` @@ -30,7 +29,7 @@ This is NOT an official Google product. RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) ``` -#### Isolating local processes (run it once, and exit) +#### Isolation of local processes ``` $ ./nsjail -Mo --chroot /chroot/ --user 99999 --group 99999 -- /bin/sh -i / $ ifconfig -a @@ -45,7 +44,7 @@ This is NOT an official Google product. $ ``` -#### Isolating local processes (and re-running them) +#### Isolation of local processes (and re-running them) ``` $ ./nsjail -Mr --chroot /chroot/ --user 99999 --group 99999 -- /bin/sh -i BusyBox v1.21.1 (Ubuntu 1:1.21.0-1ubuntu1) built-in shell (ash) @@ -61,4 +60,85 @@ Type: ``` ./nsjail --help' ``` -the commandline options are reasonably well-documented +The commandline options are reasonably well-documented +``` +Usage: ./nsjail [options] -- path_to_command [args] +Options: + --help|-h + Help plz.. + --mode|-M [val] + Execution mode (default: l [MODE_LISTEN_TCP]): + l: Listen to connections on a TCP port (specified with --port) [MODE_LISTEN_TCP] + o: Immediately launch a single process on a console [MODE_STANDALONE_ONCE] + r: Immediately launch a single process on a console, keep doing it forever [MODE_STANDALONE_RERUN] + --chroot|-c [val] + Directory containing / of the jail (default: '/chroot') + --user|-u [val] + Username/uid of processess inside the jail (default: 'nobody') + --group|-g [val] + Groupname/gid of processess inside the jail (default: 'nogroup') + --hostname|-H [val] + UTS name (hostname) of the jail (default: 'NSJAIL') + --port|-p [val] + TCP port to bind to (only in [MODE_LISTEN_TCP]) (default: 31337) + --max_conns_per_ip|-i [val] + Maximum number of connections per one IP (default: 0 (unlimited)) + --log|-l [val] + Log file (default: stderr) + --time_limit|-t [val] + Maximum time that a jail can exist, in seconds (default: 600) + --daemon|-d + Daemonize after start? (default: false) + --verbose|-v + Verbose output (default: false) + --keep_env|-e + Should all environment variables be passed to the child? (default: false) + --keep_caps + Don't drop capabilities (DANGEROUS) (default: false) + --rlimit_as [val] + RLIMIT_AS in MB, 'max' for RLIM_INFINITY, 'def' for the current value (default: 512) + --rlimit_core [val] + RLIMIT_CORE in MB, 'max' for RLIM_INFINITY, 'def' for the current value (default: 0) + --rlimit_cpu [val] + RLIMIT_CPU, 'max' for RLIM_INFINITY, 'def' for the current value (default: 600) + --rlimit_fsize [val] + RLIMIT_FSIZE in MB, 'max' for RLIM_INFINITY, 'def' for the current value (default: 1) + --rlimit_nofile [val] + RLIMIT_NOFILE, 'max' for RLIM_INFINITY, 'def' for the current value (default: 32) + --rlimit_nproc [val] + RLIMIT_NPROC, 'max' for RLIM_INFINITY, 'def' for the current value (default: 'def') + --rlimit_stack [val] + RLIMIT_STACK in MB, 'max' for RLIM_INFINITY, 'def' for the current value (default: 'def') + --persona_addr_compat_layout + personality(ADDR_COMPAT_LAYOUT) (default: false) + --persona_mmap_page_zero + personality(MMAP_PAGE_ZERO) (default: false) + --persona_read_implies_exec + personality(READ_IMPLIES_EXEC) (default: false) + --persona_addr_limit_3gb + personality(ADDR_LIMIT_3GB) (default: false) + --persona_addr_no_randomize + personality(ADDR_NO_RANDOMIZE) (default: false) + --disable_clone_newnet|-N + Enable networking inside the jail (default: false) + --disable_clone_newuser + Don't use CLONE_NEWUSER (default: false) + --disable_clone_newns + Don't use CLONE_NEWNS (default: false) + --disable_clone_newpid + Don't use CLONE_NEWPID (default: false) + --disable_clone_newipc + Don't use CLONE_NEWIPC (default: false) + --disable_clone_newuts + Don't use CLONE_NEWUTS (default: false) + --disable_sandbox + Don't enable the seccomp-bpf sandboxing (default: false) + --rw + Mount / as RW (default: RO) + --silent + Redirect child's fd:0/1/2 to /dev/null (default: false) + --bindmount|-B [val] + List of mountpoints to be mounted --bind inside the container. Can be specified multiple times (default: none) + --tmpfsmount|-T [val] + List of mountpoints to be mounted as tmpfs inside the container. Can be specified multiple times (default: none) +```