#include <stdlib.h>
#include <unistd.h>
-#include <values.h>
#include <errno.h>
#include <string.h>
#include <sys/stat.h>
#include <sched.h>
#include <linux/limits.h>
-#include "elf.h"
#include "capabilities.h"
+#include "elf.h"
+#include "fs.h"
+#include "jail.h"
#include "log.h"
-#include <libubox/list.h>
#include <libubox/uloop.h>
#define STACK_SIZE (1024 * 1024)
-#define OPT_ARGS "P:S:C:n:r:w:d:psulo"
+#define OPT_ARGS "S:C:n:r:w:d:psuloc"
static struct {
- char *path;
char *name;
char **jail_argv;
char *seccomp;
char *capabilities;
+ int no_new_privs;
int namespace;
int procfs;
int ronly;
int sysfs;
} opts;
-struct extra {
- struct list_head list;
-
- const char *path;
- const char *name;
- int readonly;
-};
-
-static LIST_HEAD(extras);
-
extern int pivot_root(const char *new_root, const char *put_old);
int debug = 0;
return ret;
}
-static int mount_bind(const char *root, const char *path, const char *name, int readonly, int error)
+int mount_bind(const char *root, const char *path, int readonly, int error)
{
- const char *p = path;
struct stat s;
- char old[PATH_MAX];
char new[PATH_MAX];
int fd;
- if (strstr(p, "local"))
- p = "/lib";
-
- snprintf(old, sizeof(old), "%s/%s", path, name);
- snprintf(new, sizeof(new), "%s%s", root, p);
-
- mkdir_p(new, 0755);
-
- snprintf(new, sizeof(new), "%s%s/%s", root, p, name);
-
- if (stat(old, &s)) {
- ERROR("%s does not exist\n", old);
+ if (stat(path, &s)) {
+ ERROR("stat(%s) failed: %s\n", path, strerror(errno));
return error;
}
+ snprintf(new, sizeof(new), "%s%s", root, path);
if (S_ISDIR(s.st_mode)) {
mkdir_p(new, 0755);
} else {
+ mkdir_p(dirname(new), 0755);
+ snprintf(new, sizeof(new), "%s%s", root, path);
fd = creat(new, 0644);
if (fd == -1) {
ERROR("failed to create %s: %s\n", new, strerror(errno));
close(fd);
}
- if (mount(old, new, NULL, MS_BIND, NULL)) {
- ERROR("failed to mount -B %s %s: %s\n", old, new, strerror(errno));
+ if (mount(path, new, NULL, MS_BIND, NULL)) {
+ ERROR("failed to mount -B %s %s: %s\n", path, new, strerror(errno));
return -1;
}
return -1;
}
- DEBUG("mount -B %s %s\n", old, new);
+ DEBUG("mount -B %s %s\n", path, new);
return 0;
}
static int build_jail_fs(void)
{
- struct library *l;
- struct extra *m;
+ char jail_root[] = "/tmp/ujail-XXXXXX";
+ if (mkdtemp(jail_root) == NULL) {
+ ERROR("mkdtemp(jail_root) failed: %s\n", strerror(errno));
+ return -1;
+ }
- if (mount("tmpfs", opts.path, "tmpfs", MS_NOATIME, "mode=0755")) {
+ if (mount("tmpfs", jail_root, "tmpfs", MS_NOATIME, "mode=0755")) {
ERROR("tmpfs mount failed %s\n", strerror(errno));
return -1;
}
- if (chdir(opts.path)) {
+ if (chdir(jail_root)) {
ERROR("failed to chdir() in the jail root\n");
return -1;
}
- init_library_search();
-
- if (elf_load_deps(*opts.jail_argv)) {
+ if (add_path_and_deps(*opts.jail_argv, 1, -1, 0)) {
ERROR("failed to load dependencies\n");
return -1;
}
- if (opts.seccomp && elf_load_deps("libpreload-seccomp.so")) {
+ if (opts.seccomp && add_path_and_deps("libpreload-seccomp.so", 1, -1, 1)) {
ERROR("failed to load libpreload-seccomp.so\n");
return -1;
}
- avl_for_each_element(&libraries, l, avl)
- if (mount_bind(opts.path, l->path, l->name, 1, -1))
- return -1;
-
- list_for_each_entry(m, &extras, list)
- if (mount_bind(opts.path, m->path, m->name, m->readonly, 0))
- return -1;
-
- char *mpoint;
- if (asprintf(&mpoint, "%s/old", opts.path) < 0) {
- ERROR("failed to alloc pivot path: %s\n", strerror(errno));
+ if (mount_all(jail_root)) {
+ ERROR("mount_all() failed\n");
return -1;
}
- mkdir_p(mpoint, 0755);
- if (pivot_root(opts.path, mpoint) == -1) {
- ERROR("pivot_root failed:%s\n", strerror(errno));
- free(mpoint);
+
+ char dirbuf[sizeof(jail_root) + 4];
+ snprintf(dirbuf, sizeof(dirbuf), "%s/old", jail_root);
+ mkdir(dirbuf, 0755);
+
+ if (pivot_root(jail_root, dirbuf) == -1) {
+ ERROR("pivot_root failed: %s\n", strerror(errno));
return -1;
}
- free(mpoint);
+
+ snprintf(dirbuf, sizeof(dirbuf), "/old%s", jail_root);
+ rmdir(dirbuf);
umount2("/old", MNT_DETACH);
rmdir("/old");
+
if (opts.procfs) {
mkdir("/proc", 0755);
mount("proc", "/proc", "proc", MS_NOATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID, 0);
fprintf(stderr, " -d <num>\tshow debug log (increase num to increase verbosity)\n");
fprintf(stderr, " -S <file>\tseccomp filter config\n");
fprintf(stderr, " -C <file>\tcapabilities drop config\n");
+ fprintf(stderr, " -c\t\tset PR_SET_NO_NEW_PRIVS\n");
fprintf(stderr, " -n <name>\tthe name of the jail\n");
fprintf(stderr, "namespace jail options:\n");
- fprintf(stderr, " -P <path>\tpath where the jail will be staged\n");
fprintf(stderr, " -r <file>\treadonly files that should be staged\n");
fprintf(stderr, " -w <file>\twriteable files that should be staged\n");
fprintf(stderr, " -p\t\tjail has /proc\n");
if (opts.capabilities && drop_capabilities(opts.capabilities))
exit(EXIT_FAILURE);
+ if (opts.no_new_privs && prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
+ ERROR("prctl(PR_SET_NO_NEW_PRIVS) failed: %s\n", strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+
INFO("exec-ing %s\n", *opts.jail_argv);
execve(*opts.jail_argv, opts.jail_argv, envp);
- //we get there only if execve fails
+ /* we get there only if execve fails */
ERROR("failed to execve %s: %s\n", *opts.jail_argv, strerror(errno));
exit(EXIT_FAILURE);
}
.cb = jail_process_handler,
};
-static void add_extra(char *name, int readonly)
-{
- struct extra *f;
-
- if (*name != '/') {
- ERROR("%s is not an absolute path\n", name);
- return;
- }
-
- f = calloc(1, sizeof(struct extra));
-
- f->name = basename(name);
- f->path = dirname(strdup(name));
- f->readonly = readonly;
-
- list_add_tail(&f->list, &extras);
-}
-
int main(int argc, char **argv)
{
uid_t uid = getuid();
char log[] = "/dev/log";
char ubus[] = "/var/run/ubus.sock";
- int ret = EXIT_SUCCESS;
int ch;
if (uid) {
}
umask(022);
+ mount_list_init();
+ init_library_search();
while ((ch = getopt(argc, argv, OPT_ARGS)) != -1) {
switch (ch) {
break;
case 'S':
opts.seccomp = optarg;
- add_extra(optarg, 1);
+ add_mount(optarg, 1, -1);
break;
case 'C':
opts.capabilities = optarg;
- add_extra(optarg, 1);
+ add_mount(optarg, 1, -1);
break;
- case 'P':
- opts.namespace = 1;
- opts.path = optarg;
+ case 'c':
+ opts.no_new_privs = 1;
break;
case 'n':
opts.name = optarg;
break;
case 'r':
opts.namespace = 1;
- add_extra(optarg, 1);
+ add_path_and_deps(optarg, 1, 0, 0);
break;
case 'w':
opts.namespace = 1;
- add_extra(optarg, 0);
+ add_path_and_deps(optarg, 0, 0, 0);
break;
case 'u':
opts.namespace = 1;
- add_extra(ubus, 0);
+ add_mount(ubus, 0, -1);
break;
case 'l':
opts.namespace = 1;
- add_extra(log, 0);
+ add_mount(log, 0, -1);
break;
}
}
- //no <binary> param found
+ /* no <binary> param found */
if (argc - optind < 1) {
usage();
return EXIT_FAILURE;
if (opts.name)
prctl(PR_SET_NAME, opts.name, NULL, NULL, NULL);
- if (opts.namespace && !opts.path && asprintf(&opts.path, "/tmp/%s", basename(*opts.jail_argv)) == -1) {
- ERROR("failed to asprintf root path: %s\n", strerror(errno));
- return EXIT_FAILURE;
- }
-
- if (opts.namespace && mkdir(opts.path, 0755)) {
- ERROR("unable to create root path: %s (%s)\n", opts.path, strerror(errno));
- return EXIT_FAILURE;
- }
-
uloop_init();
if (opts.namespace) {
jail_process.pid = clone(spawn_jail,
}
if (jail_process.pid > 0) {
- //parent process
+ /* parent process */
uloop_process_add(&jail_process);
uloop_run();
uloop_done();
kill(jail_process.pid, SIGTERM);
waitpid(jail_process.pid, NULL, 0);
}
+ return jail_return_code;
} else if (jail_process.pid == 0) {
- //fork child process
+ /* fork child process */
return exec_jail();
} else {
ERROR("failed to clone/fork: %s\n", strerror(errno));
- ret = EXIT_FAILURE;
- }
-
- if (opts.namespace && rmdir(opts.path)) {
- ERROR("Unable to remove root path: %s (%s)\n", opts.path, strerror(errno));
- ret = EXIT_FAILURE;
+ return EXIT_FAILURE;
}
-
- if (ret)
- return ret;
-
- return jail_return_code;
}