#include <signal.h>
#include <sched.h>
#include <unistd.h>
+#include <attr/xattr.h>
#include <sys/types.h>
#include <sys/syscall.h>
#include <sys/mount.h>
static char *arg_user = NULL;
static char **arg_controllers = NULL;
static char *arg_uuid = NULL;
+static char *arg_machine = NULL;
static bool arg_private_network = false;
static bool arg_read_only = false;
static bool arg_boot = false;
printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
"Spawn a minimal namespace container for debugging, testing and building.\n\n"
" -h --help Show this help\n"
- " --version Print version string\n"
+ " --version Print version string\n"
" -D --directory=NAME Root directory for the container\n"
" -b --boot Boot up full system (i.e. invoke init)\n"
" -u --user=USER Run the command under specified user or uid\n"
" -C --controllers=LIST Put the container in specified comma-separated\n"
" cgroup hierarchies\n"
" --uuid=UUID Set a specific machine UUID for the container\n"
+ " -M --machine=NAME Set the machine name for the container\n"
" --private-network Disable network in container\n"
" --read-only Mount the root directory read-only\n"
" --capability=CAP In addition to the default, retain specified\n"
{ "link-journal", required_argument, NULL, ARG_LINK_JOURNAL },
{ "bind", required_argument, NULL, ARG_BIND },
{ "bind-ro", required_argument, NULL, ARG_BIND_RO },
+ { "machine", required_argument, NULL, 'M' },
{ NULL, 0, NULL, 0 }
};
case 'u':
free(arg_user);
- if (!(arg_user = strdup(optarg))) {
- log_error("Failed to duplicate user name.");
- return -ENOMEM;
- }
+ arg_user = strdup(optarg);
+ if (!arg_user)
+ return log_oom();
break;
case 'C':
strv_free(arg_controllers);
arg_controllers = strv_split(optarg, ",");
- if (!arg_controllers) {
- log_error("Failed to split controllers list.");
- return -ENOMEM;
- }
- strv_uniq(arg_controllers);
+ if (!arg_controllers)
+ return log_oom();
+ cg_shorten_controllers(arg_controllers);
break;
case ARG_PRIVATE_NETWORK:
arg_uuid = optarg;
break;
+ case 'M':
+ if (!hostname_is_valid(optarg)) {
+ log_error("Invalid machine name: %s", optarg);
+ return -EINVAL;
+ }
+
+ free(arg_machine);
+ arg_machine = strdup(optarg);
+ if (!arg_machine)
+ return log_oom();
+
+ break;
+
case ARG_READ_ONLY:
arg_read_only = true;
break;
int r = 0;
for (k = 0; k < ELEMENTSOF(mount_table); k++) {
- char _cleanup_free_ *where = NULL;
+ _cleanup_free_ char *where = NULL;
int t;
where = strjoin(dest, "/", mount_table[k].where, NULL);
}
static int setup_resolv_conf(const char *dest) {
- char *where;
+ char _cleanup_free_ *where = NULL;
+ _cleanup_close_ int fd = -1;
assert(dest);
if (!where)
return log_oom();
+ fd = open(where, O_WRONLY|O_CREAT|O_EXCL|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, 0644);
+
/* We don't really care for the results of this really. If it
* fails, it fails, but meh... */
- if (mount("/etc/resolv.conf", where, "bind", MS_BIND, NULL) >= 0)
- mount("/etc/resolv.conf", where, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL);
-
- free(where);
+ if (mount("/etc/resolv.conf", where, "bind", MS_BIND, NULL) < 0)
+ log_warning("Failed to bind mount /etc/resolv.conf: %m");
+ else
+ if (mount("/etc/resolv.conf", where, "bind",
+ MS_BIND|MS_REMOUNT|MS_RDONLY, NULL) < 0) {
+ log_error("Failed to remount /etc/resolv.conf readonly: %m");
+ return -errno;
+ }
return 0;
}
static int setup_boot_id(const char *dest) {
- char _cleanup_free_ *from = NULL, *to = NULL;
+ _cleanup_free_ char *from = NULL, *to = NULL;
sd_id128_t rnd;
char as_uuid[37];
int r;
SD_ID128_FORMAT_VAL(rnd));
char_array_0(as_uuid);
- r = write_one_line_file(from, as_uuid);
+ r = write_string_file(from, as_uuid);
if (r < 0) {
log_error("Failed to write boot id: %s", strerror(-r));
return r;
if (mount(from, to, "bind", MS_BIND, NULL) < 0) {
log_error("Failed to bind mount boot id: %m");
r = -errno;
- } else
- mount(from, to, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL);
+ } else if (mount(from, to, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL))
+ log_warning("Failed to make boot id read-only: %m");
unlink(from);
return r;
const char *d;
int r = 0;
- mode_t _cleanup_umask_ u;
+ _cleanup_umask_ mode_t u;
assert(dest);
NULSTR_FOREACH(d, devnodes) {
struct stat st;
- char _cleanup_free_ *from = NULL, *to = NULL;
+ _cleanup_free_ char *from = NULL, *to = NULL;
asprintf(&from, "/dev/%s", d);
asprintf(&to, "%s/dev/%s", dest, d);
static int setup_dev_console(const char *dest, const char *console) {
struct stat st;
- char _cleanup_free_ *to = NULL;
+ _cleanup_free_ char *to = NULL;
int r;
- mode_t _cleanup_umask_ u;
+ _cleanup_umask_ mode_t u;
assert(dest);
assert(console);
}
static int setup_kmsg(const char *dest, int kmsg_socket) {
- char _cleanup_free_ *from = NULL, *to = NULL;
+ _cleanup_free_ char *from = NULL, *to = NULL;
int r, fd, k;
- mode_t _cleanup_umask_ u;
+ _cleanup_umask_ mode_t u;
union {
struct cmsghdr cmsghdr;
uint8_t buf[CMSG_SPACE(sizeof(int))];
- } control;
- struct msghdr mh;
+ } control = {};
+ struct msghdr mh = {
+ .msg_control = &control,
+ .msg_controllen = sizeof(control),
+ };
struct cmsghdr *cmsg;
assert(dest);
return -errno;
}
- zero(mh);
- zero(control);
-
- mh.msg_control = &control;
- mh.msg_controllen = sizeof(control);
-
cmsg = CMSG_FIRSTHDR(&mh);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
}
static int setup_hostname(void) {
- char *hn;
- int r = 0;
-
- hn = path_get_file_name(arg_directory);
- if (hn) {
- hn = strdup(hn);
- if (!hn)
- return -ENOMEM;
-
- hostname_cleanup(hn);
- if (!isempty(hn))
- if (sethostname(hn, strlen(hn)) < 0)
- r = -errno;
-
- free(hn);
- }
+ if (sethostname(arg_machine, strlen(arg_machine)) < 0)
+ return -errno;
- return r;
+ return 0;
}
static int setup_journal(const char *directory) {
sd_id128_t machine_id;
- char _cleanup_free_ *p = NULL, *b = NULL, *q = NULL, *d = NULL;
+ _cleanup_free_ char *p = NULL, *b = NULL, *q = NULL, *d = NULL;
char *id;
int r;
return 0;
}
-static int drop_capabilities(void) {
- return capability_bounding_set_drop(~arg_retain, false);
+static int setup_cgroup(const char *path) {
+ char **c;
+ int r;
+
+ r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, path, 1);
+ if (r < 0) {
+ log_error("Failed to create cgroup: %s", strerror(-r));
+ return r;
+ }
+
+ STRV_FOREACH(c, arg_controllers) {
+ r = cg_create_and_attach(*c, path, 1);
+ if (r < 0)
+ log_warning("Failed to create cgroup in controller %s: %s", *c, strerror(-r));
+ }
+
+ return 0;
}
-static int is_os_tree(const char *path) {
- int r;
- char *p;
- /* We use /bin/sh as flag file if something is an OS */
+static int save_attributes(const char *cgroup, pid_t pid, const char *uuid, const char *directory) {
+ _cleanup_free_ char *path = NULL;
+ char buf[DECIMAL_STR_MAX(pid_t)];
+ int r = 0, k;
- if (asprintf(&p, "%s/bin/sh", path) < 0)
- return -ENOMEM;
+ assert(cgroup);
+ assert(pid >= 0);
+ assert(arg_directory);
- r = access(p, F_OK);
- free(p);
+#ifdef HAVE_XATTR
+ assert_se(snprintf(buf, sizeof(buf), "%lu", (unsigned long) pid) < (int) sizeof(buf));
+
+ r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, cgroup, NULL, &path);
+ if (r < 0) {
+ log_error("Failed to get path: %s", strerror(-r));
+ return r;
+ }
+
+ r = setxattr(path, "trusted.init_pid", buf, strlen(buf), XATTR_CREATE);
+ if (r < 0)
+ log_warning("Failed to set %s attribute on %s: %m", "trusted.init_pid", path);
+
+ if (uuid) {
+ k = setxattr(path, "trusted.machine_id", uuid, strlen(uuid), XATTR_CREATE);
+ if (k < 0) {
+ log_warning("Failed to set %s attribute on %s: %m", "trusted.machine_id", path);
+ if (r == 0)
+ r = k;
+ }
+ }
- return r < 0 ? 0 : 1;
+ k = setxattr(path, "trusted.root_directory", directory, strlen(directory), XATTR_CREATE);
+ if (k < 0) {
+ log_warning("Failed to set %s attribute on %s: %m", "trusted.root_directory", path);
+ if (r == 0)
+ r = k;
+ }
+#endif
+ return r;
+}
+
+static int drop_capabilities(void) {
+ return capability_bounding_set_drop(~arg_retain, false);
}
static int process_pty(int master, pid_t pid, sigset_t *mask) {
int main(int argc, char *argv[]) {
pid_t pid = 0;
int r = EXIT_FAILURE, k;
- char *oldcg = NULL, *newcg = NULL;
- char **controller = NULL;
- int master = -1, n_fd_passed;
+ _cleanup_free_ char *machine_root = NULL, *newcg = NULL;
+ _cleanup_close_ int master = -1;
+ int n_fd_passed;
const char *console = NULL;
struct termios saved_attr, raw_attr;
sigset_t mask;
arg_directory = get_current_dir_name();
if (!arg_directory) {
- log_error("Failed to determine path");
+ log_error("Failed to determine path, please use -D.");
goto finish;
}
path_kill_slashes(arg_directory);
+ if (!arg_machine) {
+ arg_machine = strdup(path_get_file_name(arg_directory));
+ if (!arg_machine) {
+ log_oom();
+ goto finish;
+ }
+
+ hostname_cleanup(arg_machine);
+ if (isempty(arg_machine)) {
+ log_error("Failed to determine machine name automatically, please use -M.");
+ goto finish;
+ }
+ }
+
if (geteuid() != 0) {
log_error("Need to be root.");
goto finish;
goto finish;
}
- if (is_os_tree(arg_directory) <= 0) {
+ if (path_is_os_tree(arg_directory) <= 0) {
log_error("Directory %s doesn't look like an OS root directory. Refusing.", arg_directory);
goto finish;
}
fdset_close_others(fds);
log_open();
- k = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, &oldcg);
+ k = cg_get_machine_path(&machine_root);
if (k < 0) {
- log_error("Failed to determine current cgroup: %s", strerror(-k));
+ log_error("Failed to determine machine cgroup path: %s", strerror(-k));
goto finish;
}
- if (asprintf(&newcg, "%s/nspawn-%lu", oldcg, (unsigned long) getpid()) < 0) {
+ newcg = strjoin(machine_root, "/", arg_machine, NULL);
+ if (!newcg) {
log_error("Failed to allocate cgroup path.");
goto finish;
}
- k = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, newcg, 0);
- if (k < 0) {
- log_error("Failed to create cgroup: %s", strerror(-k));
- goto finish;
- }
+ r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, newcg, false);
+ if (r <= 0 && r != -ENOENT) {
+ log_error("Container already running.");
+
+ free(newcg);
+ newcg = NULL;
- STRV_FOREACH(controller, arg_controllers) {
- k = cg_create_and_attach(*controller, newcg, 0);
- if (k < 0)
- log_warning("Failed to create cgroup in controller %s: %s", *controller, strerror(-k));
+ goto finish;
}
master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY);
}
if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) {
- log_error("Failed to create kmsg socket pair");
+ log_error("Failed to create kmsg socket pair.");
goto finish;
}
for (;;) {
siginfo_t status;
- int pipefd[2];
+ int pipefd[2], pipefd2[2];
if (pipe2(pipefd, O_NONBLOCK|O_CLOEXEC) < 0) {
log_error("pipe2(): %m");
goto finish;
}
+ if (pipe2(pipefd2, O_NONBLOCK|O_CLOEXEC) < 0) {
+ log_error("pipe2(): %m");
+ close_pipe(pipefd);
+ goto finish;
+ }
+
pid = syscall(__NR_clone, SIGCHLD|CLONE_NEWIPC|CLONE_NEWNS|CLONE_NEWPID|CLONE_NEWUTS|(arg_private_network ? CLONE_NEWNET : 0), NULL);
if (pid < 0) {
if (errno == EINVAL)
if (envp[n_env])
n_env ++;
+ /* Wait for the parent process to log our PID */
close_nointr_nofail(pipefd[1]);
fd_wait_for_event(pipefd[0], POLLHUP, -1);
close_nointr_nofail(pipefd[0]);
goto child_fail;
}
+ if (setup_cgroup(newcg) < 0)
+ goto child_fail;
+
+ close_pipe(pipefd2);
+
/* Mark everything as slave, so that we still
* receive mounts from the real root, but don't
* propagate mounts to the real root. */
}
if ((asprintf((char **)(envp + n_env++), "LISTEN_FDS=%u", n_fd_passed) < 0) ||
- (asprintf((char **)(envp + n_env++), "LISTEN_PID=%lu", (unsigned long) getpid()) < 0)) {
+ (asprintf((char **)(envp + n_env++), "LISTEN_PID=%lu", (unsigned long) 1) < 0)) {
log_oom();
goto child_fail;
}
close_nointr_nofail(pipefd[0]);
close_nointr_nofail(pipefd[1]);
+ /* Wait for the child process to establish cgroup hierarchy */
+ close_nointr_nofail(pipefd2[1]);
+ fd_wait_for_event(pipefd2[0], POLLHUP, -1);
+ close_nointr_nofail(pipefd2[0]);
+
+ save_attributes(newcg, pid, arg_uuid, arg_directory);
+
fdset_free(fds);
fds = NULL;
if (saved_attr_valid)
tcsetattr(STDIN_FILENO, TCSANOW, &saved_attr);
- if (master >= 0)
- close_nointr_nofail(master);
-
close_pipe(kmsg_socket_pair);
- if (oldcg)
- cg_attach(SYSTEMD_CGROUP_CONTROLLER, oldcg, 0);
-
if (newcg)
cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, newcg, true);
free(arg_directory);
+ free(arg_machine);
strv_free(arg_controllers);
- free(oldcg);
- free(newcg);
fdset_free(fds);