nspawn: add new --no-net switch to turn off networking in the container

This commit is contained in:
Lennart Poettering 2011-08-02 04:49:37 +02:00
parent 72b9ed828b
commit a41fe3a293
3 changed files with 33 additions and 7 deletions

View file

@ -1341,7 +1341,8 @@ systemd_cgls_LDADD = \
systemd_nspawn_SOURCES = \
src/nspawn.c \
src/cgroup-util.c
src/cgroup-util.c \
src/loopback-setup.c
systemd_nspawn_CFLAGS = \
$(AM_CFLAGS)

View file

@ -123,6 +123,7 @@
<variablelist>
<varlistentry>
<term><option>--help</option></term>
<term><option>-h</option></term>
<listitem><para>Prints a short help
text and exits.</para></listitem>
@ -152,6 +153,16 @@
</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--no-net</option></term>
<listitem><para>Turn off networking in
the container. This makes all network
interfaces unavailable in the
container, with the exception of the
loopback device.</para></listitem>
</varlistentry>
</variablelist>
</refsect1>

View file

@ -44,9 +44,11 @@
#include "cgroup-util.h"
#include "sd-daemon.h"
#include "strv.h"
#include "loopback-setup.h"
static char *arg_directory = NULL;
static char *arg_user = NULL;
static bool arg_no_net = false;
static int help(void) {
@ -54,7 +56,8 @@ static int help(void) {
"Spawn a minimal namespace container for debugging, testing and building.\n\n"
" -h --help Show this help\n"
" -D --directory=NAME Root directory for the container\n"
" -u --user=USER Run the command under specified user or uid\n",
" -u --user=USER Run the command under specified user or uid\n"
" --no-net Disable network in container\n",
program_invocation_short_name);
return 0;
@ -62,11 +65,16 @@ static int help(void) {
static int parse_argv(int argc, char *argv[]) {
enum {
ARG_NO_NET = 0x100
};
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "directory", required_argument, NULL, 'D' },
{ "user", optional_argument, NULL, 'u' },
{ NULL, 0, NULL, 0 }
{ "help", no_argument, NULL, 'h' },
{ "directory", required_argument, NULL, 'D' },
{ "user", required_argument, NULL, 'u' },
{ "no-net", no_argument, NULL, ARG_NO_NET },
{ NULL, 0, NULL, 0 }
};
int c;
@ -100,6 +108,10 @@ static int parse_argv(int argc, char *argv[]) {
break;
case ARG_NO_NET:
arg_no_net = true;
break;
case '?':
return -EINVAL;
@ -698,7 +710,7 @@ int main(int argc, char *argv[]) {
sigset_add_many(&mask, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, -1);
assert_se(sigprocmask(SIG_BLOCK, &mask, NULL) == 0);
if ((pid = syscall(__NR_clone, SIGCHLD|CLONE_NEWIPC|CLONE_NEWNS|CLONE_NEWPID|CLONE_NEWUTS, NULL)) < 0) {
if ((pid = syscall(__NR_clone, SIGCHLD|CLONE_NEWIPC|CLONE_NEWNS|CLONE_NEWPID|CLONE_NEWUTS|(arg_no_net ? CLONE_NEWNET : 0), NULL)) < 0) {
log_error("clone() failed: %m");
goto finish;
}
@ -777,6 +789,8 @@ int main(int argc, char *argv[]) {
umask(0022);
loopback_setup();
if (drop_capabilities() < 0)
goto child_fail;