/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved. * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ /* * The general pattern of use here: * 1) Construct a minijail with minijail_new() * 2) Apply the desired restrictions to it * 3) Enter it, which locks the current process inside it, or: * 3) Run a process inside it * 4) Destroy it. */ #ifndef _LIBMINIJAIL_H_ #define _LIBMINIJAIL_H_ #include #include #ifdef __cplusplus extern "C" { #endif enum { MINIJAIL_ERR_PRELOAD = 252, MINIJAIL_ERR_JAIL = 253, MINIJAIL_ERR_INIT = 254, }; struct minijail; /* Allocates a new minijail with no restrictions. */ struct minijail *minijail_new(void); /* * These functions add restrictions to the minijail. They are not applied until * minijail_enter() is called. See the documentation in minijail0.1 for * explanations in detail of what the restrictions do. */ void minijail_change_uid(struct minijail *j, uid_t uid); void minijail_change_gid(struct minijail *j, gid_t gid); /* Copies |list|. */ void minijail_set_supplementary_gids(struct minijail *j, size_t size, const gid_t *list); /* Stores user to change to and copies |user| for internal consistency. */ int minijail_change_user(struct minijail *j, const char *user); /* Does not take ownership of |group|. */ int minijail_change_group(struct minijail *j, const char *group); void minijail_use_seccomp(struct minijail *j); void minijail_no_new_privs(struct minijail *j); void minijail_use_seccomp_filter(struct minijail *j); void minijail_parse_seccomp_filters(struct minijail *j, const char *path); void minijail_log_seccomp_filter_failures(struct minijail *j); void minijail_use_caps(struct minijail *j, uint64_t capmask); void minijail_reset_signal_mask(struct minijail *j); void minijail_namespace_vfs(struct minijail *j); void minijail_namespace_enter_vfs(struct minijail *j, const char *ns_path); void minijail_namespace_ipc(struct minijail *j); void minijail_namespace_net(struct minijail *j); void minijail_namespace_enter_net(struct minijail *j, const char *ns_path); /* * Implies namespace_vfs and remount_proc_readonly. * WARNING: this is NOT THREAD SAFE. See the block comment in . */ void minijail_namespace_pids(struct minijail *j); void minijail_namespace_user(struct minijail *j); int minijail_uidmap(struct minijail *j, const char *uidmap); int minijail_gidmap(struct minijail *j, const char *gidmap); void minijail_remount_proc_readonly(struct minijail *j); void minijail_run_as_init(struct minijail *j); int minijail_write_pid_file(struct minijail *j, const char *path); void minijail_inherit_usergroups(struct minijail *j); void minijail_disable_ptrace(struct minijail *j); /* * Changes the jailed process's syscall table to the alt_syscall table * named |table|. */ int minijail_use_alt_syscall(struct minijail *j, const char *table); /* * Adds the jailed process to the cgroup given by |path|. |path| should be the * full path to the cgroups "tasks" file. * Example: /sys/fs/cgroup/cpu/jailed_procs/tasks adds to the "jailed_procs" cpu * cgroup. */ int minijail_add_to_cgroup(struct minijail *j, const char *path); /* * minijail_enter_chroot: enables chroot() restriction for @j * @j minijail to apply restriction to * @dir directory to chroot() to. Owned by caller. * * Enters @dir, binding all bind mounts specified with minijail_bind() into * place. Requires @dir to contain all necessary directories for bind mounts * (i.e., if you have requested a bind mount at /etc, /etc must exist in @dir.) * * Returns 0 on success. */ int minijail_enter_chroot(struct minijail *j, const char *dir); int minijail_enter_pivot_root(struct minijail *j, const char *dir); /* * minijail_get_original_path: returns the path of a given file outside of the * chroot. * @j minijail to obtain the path from. * @chroot_path path inside of the chroot() to. * * When executing a binary in a chroot or pivot_root, return path to the binary * outside of the chroot. * * Returns a string containing the path. This must be freed by the caller. */ char *minijail_get_original_path(struct minijail *j, const char *chroot_path); /* * minijail_mount_tmp: enables mounting of a tmpfs filesystem on /tmp. * As be rules of bind mounts, /tmp must exist in chroot. */ void minijail_mount_tmp(struct minijail *j); /* * minijail_mount: when entering minijail @j, mounts @src at @dst with @flags * @j minijail to bind inside * @src source to bind * @dest location to bind (inside chroot) * @type type of filesystem * @flags flags passed to mount * * This may be called multiple times; all bindings will be applied in the order * of minijail_mount() calls. */ int minijail_mount(struct minijail *j, const char *src, const char *dest, const char *type, unsigned long flags); /* * minijail_bind: bind-mounts @src into @j as @dest, optionally writeable * @j minijail to bind inside * @src source to bind * @dest location to bind (inside chroot) * @writeable 1 if the bind mount should be writeable * * This may be called multiple times; all bindings will be applied in the order * of minijail_bind() calls. */ int minijail_bind(struct minijail *j, const char *src, const char *dest, int writeable); /* * Lock this process into the given minijail. Note that this procedure cannot fail, * since there is no way to undo privilege-dropping; therefore, if any part of * the privilege-drop fails, minijail_enter() will abort the entire process. * * Some restrictions cannot be enabled this way (pid namespaces) and attempting * to do so will cause an abort. */ void minijail_enter(const struct minijail *j); /* * Run the specified command in the given minijail, execve(2)-style. This is * required if minijail_namespace_pids() was used. */ int minijail_run(struct minijail *j, const char *filename, char *const argv[]); /* * Run the specified command in the given minijail, execve(2)-style. * Used with static binaries, or on systems without support for LD_PRELOAD. */ int minijail_run_no_preload(struct minijail *j, const char *filename, char *const argv[]); /* * Run the specified command in the given minijail, execve(2)-style. * Update |*pchild_pid| with the pid of the child. */ int minijail_run_pid(struct minijail *j, const char *filename, char *const argv[], pid_t *pchild_pid); /* * Run the specified command in the given minijail, execve(2)-style. * Update |*pstdin_fd| with a fd that allows writing to the child's * standard input. */ int minijail_run_pipe(struct minijail *j, const char *filename, char *const argv[], int *pstdin_fd); /* * Run the specified command in the given minijail, execve(2)-style. * Update |*pchild_pid| with the pid of the child. * Update |*pstdin_fd| with a fd that allows writing to the child's * standard input. * Update |*pstdout_fd| with a fd that allows reading from the child's * standard output. * Update |*pstderr_fd| with a fd that allows reading from the child's * standard error. */ int minijail_run_pid_pipes(struct minijail *j, const char *filename, char *const argv[], pid_t *pchild_pid, int *pstdin_fd, int *pstdout_fd, int *pstderr_fd); /* * Run the specified command in the given minijail, execve(2)-style. * Update |*pchild_pid| with the pid of the child. * Update |*pstdin_fd| with a fd that allows writing to the child's * standard input. * Update |*pstdout_fd| with a fd that allows reading from the child's * standard output. * Update |*pstderr_fd| with a fd that allows reading from the child's * standard error. * Used with static binaries, or on systems without support for LD_PRELOAD. */ int minijail_run_pid_pipes_no_preload(struct minijail *j, const char *filename, char *const argv[], pid_t *pchild_pid, int *pstdin_fd, int *pstdout_fd, int *pstderr_fd); /* * Kill the specified minijail. The minijail must have been created with pid * namespacing; if it was, all processes inside it are atomically killed. */ int minijail_kill(struct minijail *j); /* * Wait for all processed in the specified minijail to exit. Returns the exit * status of the _first_ process spawned in the jail. */ int minijail_wait(struct minijail *j); /* * Frees the given minijail. It does not matter if the process is inside the minijail or * not. */ void minijail_destroy(struct minijail *j); #ifdef __cplusplus }; /* extern "C" */ #endif #endif /* !_LIBMINIJAIL_H_ */