| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * security/tomoyo/tomoyo.c |
| * |
| * Copyright (C) 2005-2011 NTT DATA CORPORATION |
| */ |
| |
| #include <linux/lsm_hooks.h> |
| #include "common.h" |
| |
| /** |
| * tomoyo_cred_alloc_blank - Target for security_cred_alloc_blank(). |
| * |
| * @new: Pointer to "struct cred". |
| * @gfp: Memory allocation flags. |
| * |
| * Returns 0. |
| */ |
| static int tomoyo_cred_alloc_blank(struct cred *new, gfp_t gfp) |
| { |
| new->security = NULL; |
| return 0; |
| } |
| |
| /** |
| * tomoyo_cred_prepare - Target for security_prepare_creds(). |
| * |
| * @new: Pointer to "struct cred". |
| * @old: Pointer to "struct cred". |
| * @gfp: Memory allocation flags. |
| * |
| * Returns 0. |
| */ |
| static int tomoyo_cred_prepare(struct cred *new, const struct cred *old, |
| gfp_t gfp) |
| { |
| struct tomoyo_domain_info *domain = old->security; |
| new->security = domain; |
| if (domain) |
| atomic_inc(&domain->users); |
| return 0; |
| } |
| |
| /** |
| * tomoyo_cred_transfer - Target for security_transfer_creds(). |
| * |
| * @new: Pointer to "struct cred". |
| * @old: Pointer to "struct cred". |
| */ |
| static void tomoyo_cred_transfer(struct cred *new, const struct cred *old) |
| { |
| tomoyo_cred_prepare(new, old, 0); |
| } |
| |
| /** |
| * tomoyo_cred_free - Target for security_cred_free(). |
| * |
| * @cred: Pointer to "struct cred". |
| */ |
| static void tomoyo_cred_free(struct cred *cred) |
| { |
| struct tomoyo_domain_info *domain = cred->security; |
| if (domain) |
| atomic_dec(&domain->users); |
| } |
| |
| /** |
| * tomoyo_bprm_set_creds - Target for security_bprm_set_creds(). |
| * |
| * @bprm: Pointer to "struct linux_binprm". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_bprm_set_creds(struct linux_binprm *bprm) |
| { |
| /* |
| * Do only if this function is called for the first time of an execve |
| * operation. |
| */ |
| if (bprm->called_set_creds) |
| return 0; |
| #ifndef CONFIG_SECURITY_TOMOYO_OMIT_USERSPACE_LOADER |
| /* |
| * Load policy if /sbin/tomoyo-init exists and /sbin/init is requested |
| * for the first time. |
| */ |
| if (!tomoyo_policy_loaded) |
| tomoyo_load_policy(bprm->filename); |
| #endif |
| /* |
| * Release reference to "struct tomoyo_domain_info" stored inside |
| * "bprm->cred->security". New reference to "struct tomoyo_domain_info" |
| * stored inside "bprm->cred->security" will be acquired later inside |
| * tomoyo_find_next_domain(). |
| */ |
| atomic_dec(&((struct tomoyo_domain_info *) |
| bprm->cred->security)->users); |
| /* |
| * Tell tomoyo_bprm_check_security() is called for the first time of an |
| * execve operation. |
| */ |
| bprm->cred->security = NULL; |
| return 0; |
| } |
| |
| /** |
| * tomoyo_bprm_check_security - Target for security_bprm_check(). |
| * |
| * @bprm: Pointer to "struct linux_binprm". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_bprm_check_security(struct linux_binprm *bprm) |
| { |
| struct tomoyo_domain_info *domain = bprm->cred->security; |
| |
| /* |
| * Execute permission is checked against pathname passed to do_execve() |
| * using current domain. |
| */ |
| if (!domain) { |
| const int idx = tomoyo_read_lock(); |
| const int err = tomoyo_find_next_domain(bprm); |
| tomoyo_read_unlock(idx); |
| return err; |
| } |
| /* |
| * Read permission is checked against interpreters using next domain. |
| */ |
| return tomoyo_check_open_permission(domain, &bprm->file->f_path, |
| O_RDONLY); |
| } |
| |
| /** |
| * tomoyo_inode_getattr - Target for security_inode_getattr(). |
| * |
| * @mnt: Pointer to "struct vfsmount". |
| * @dentry: Pointer to "struct dentry". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_inode_getattr(const struct path *path) |
| { |
| return tomoyo_path_perm(TOMOYO_TYPE_GETATTR, path, NULL); |
| } |
| |
| /** |
| * tomoyo_path_truncate - Target for security_path_truncate(). |
| * |
| * @path: Pointer to "struct path". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_truncate(const struct path *path) |
| { |
| return tomoyo_path_perm(TOMOYO_TYPE_TRUNCATE, path, NULL); |
| } |
| |
| /** |
| * tomoyo_path_unlink - Target for security_path_unlink(). |
| * |
| * @parent: Pointer to "struct path". |
| * @dentry: Pointer to "struct dentry". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_unlink(const struct path *parent, struct dentry *dentry) |
| { |
| struct path path = { .mnt = parent->mnt, .dentry = dentry }; |
| return tomoyo_path_perm(TOMOYO_TYPE_UNLINK, &path, NULL); |
| } |
| |
| /** |
| * tomoyo_path_mkdir - Target for security_path_mkdir(). |
| * |
| * @parent: Pointer to "struct path". |
| * @dentry: Pointer to "struct dentry". |
| * @mode: DAC permission mode. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_mkdir(const struct path *parent, struct dentry *dentry, |
| umode_t mode) |
| { |
| struct path path = { .mnt = parent->mnt, .dentry = dentry }; |
| return tomoyo_path_number_perm(TOMOYO_TYPE_MKDIR, &path, |
| mode & S_IALLUGO); |
| } |
| |
| /** |
| * tomoyo_path_rmdir - Target for security_path_rmdir(). |
| * |
| * @parent: Pointer to "struct path". |
| * @dentry: Pointer to "struct dentry". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_rmdir(const struct path *parent, struct dentry *dentry) |
| { |
| struct path path = { .mnt = parent->mnt, .dentry = dentry }; |
| return tomoyo_path_perm(TOMOYO_TYPE_RMDIR, &path, NULL); |
| } |
| |
| /** |
| * tomoyo_path_symlink - Target for security_path_symlink(). |
| * |
| * @parent: Pointer to "struct path". |
| * @dentry: Pointer to "struct dentry". |
| * @old_name: Symlink's content. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_symlink(const struct path *parent, struct dentry *dentry, |
| const char *old_name) |
| { |
| struct path path = { .mnt = parent->mnt, .dentry = dentry }; |
| return tomoyo_path_perm(TOMOYO_TYPE_SYMLINK, &path, old_name); |
| } |
| |
| /** |
| * tomoyo_path_mknod - Target for security_path_mknod(). |
| * |
| * @parent: Pointer to "struct path". |
| * @dentry: Pointer to "struct dentry". |
| * @mode: DAC permission mode. |
| * @dev: Device attributes. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_mknod(const struct path *parent, struct dentry *dentry, |
| umode_t mode, unsigned int dev) |
| { |
| struct path path = { .mnt = parent->mnt, .dentry = dentry }; |
| int type = TOMOYO_TYPE_CREATE; |
| const unsigned int perm = mode & S_IALLUGO; |
| |
| switch (mode & S_IFMT) { |
| case S_IFCHR: |
| type = TOMOYO_TYPE_MKCHAR; |
| break; |
| case S_IFBLK: |
| type = TOMOYO_TYPE_MKBLOCK; |
| break; |
| default: |
| goto no_dev; |
| } |
| return tomoyo_mkdev_perm(type, &path, perm, dev); |
| no_dev: |
| switch (mode & S_IFMT) { |
| case S_IFIFO: |
| type = TOMOYO_TYPE_MKFIFO; |
| break; |
| case S_IFSOCK: |
| type = TOMOYO_TYPE_MKSOCK; |
| break; |
| } |
| return tomoyo_path_number_perm(type, &path, perm); |
| } |
| |
| /** |
| * tomoyo_path_link - Target for security_path_link(). |
| * |
| * @old_dentry: Pointer to "struct dentry". |
| * @new_dir: Pointer to "struct path". |
| * @new_dentry: Pointer to "struct dentry". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_link(struct dentry *old_dentry, const struct path *new_dir, |
| struct dentry *new_dentry) |
| { |
| struct path path1 = { .mnt = new_dir->mnt, .dentry = old_dentry }; |
| struct path path2 = { .mnt = new_dir->mnt, .dentry = new_dentry }; |
| return tomoyo_path2_perm(TOMOYO_TYPE_LINK, &path1, &path2); |
| } |
| |
| /** |
| * tomoyo_path_rename - Target for security_path_rename(). |
| * |
| * @old_parent: Pointer to "struct path". |
| * @old_dentry: Pointer to "struct dentry". |
| * @new_parent: Pointer to "struct path". |
| * @new_dentry: Pointer to "struct dentry". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_rename(const struct path *old_parent, |
| struct dentry *old_dentry, |
| const struct path *new_parent, |
| struct dentry *new_dentry) |
| { |
| struct path path1 = { .mnt = old_parent->mnt, .dentry = old_dentry }; |
| struct path path2 = { .mnt = new_parent->mnt, .dentry = new_dentry }; |
| return tomoyo_path2_perm(TOMOYO_TYPE_RENAME, &path1, &path2); |
| } |
| |
| /** |
| * tomoyo_file_fcntl - Target for security_file_fcntl(). |
| * |
| * @file: Pointer to "struct file". |
| * @cmd: Command for fcntl(). |
| * @arg: Argument for @cmd. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_file_fcntl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| if (!(cmd == F_SETFL && ((arg ^ file->f_flags) & O_APPEND))) |
| return 0; |
| return tomoyo_check_open_permission(tomoyo_domain(), &file->f_path, |
| O_WRONLY | (arg & O_APPEND)); |
| } |
| |
| /** |
| * tomoyo_file_open - Target for security_file_open(). |
| * |
| * @f: Pointer to "struct file". |
| * @cred: Pointer to "struct cred". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_file_open(struct file *f, const struct cred *cred) |
| { |
| int flags = f->f_flags; |
| /* Don't check read permission here if called from do_execve(). */ |
| if (current->in_execve) |
| return 0; |
| return tomoyo_check_open_permission(tomoyo_domain(), &f->f_path, flags); |
| } |
| |
| /** |
| * tomoyo_file_ioctl - Target for security_file_ioctl(). |
| * |
| * @file: Pointer to "struct file". |
| * @cmd: Command for ioctl(). |
| * @arg: Argument for @cmd. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_file_ioctl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| return tomoyo_path_number_perm(TOMOYO_TYPE_IOCTL, &file->f_path, cmd); |
| } |
| |
| /** |
| * tomoyo_path_chmod - Target for security_path_chmod(). |
| * |
| * @path: Pointer to "struct path". |
| * @mode: DAC permission mode. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_chmod(const struct path *path, umode_t mode) |
| { |
| return tomoyo_path_number_perm(TOMOYO_TYPE_CHMOD, path, |
| mode & S_IALLUGO); |
| } |
| |
| /** |
| * tomoyo_path_chown - Target for security_path_chown(). |
| * |
| * @path: Pointer to "struct path". |
| * @uid: Owner ID. |
| * @gid: Group ID. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_chown(const struct path *path, kuid_t uid, kgid_t gid) |
| { |
| int error = 0; |
| if (uid_valid(uid)) |
| error = tomoyo_path_number_perm(TOMOYO_TYPE_CHOWN, path, |
| from_kuid(&init_user_ns, uid)); |
| if (!error && gid_valid(gid)) |
| error = tomoyo_path_number_perm(TOMOYO_TYPE_CHGRP, path, |
| from_kgid(&init_user_ns, gid)); |
| return error; |
| } |
| |
| /** |
| * tomoyo_path_chroot - Target for security_path_chroot(). |
| * |
| * @path: Pointer to "struct path". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_path_chroot(const struct path *path) |
| { |
| return tomoyo_path_perm(TOMOYO_TYPE_CHROOT, path, NULL); |
| } |
| |
| /** |
| * tomoyo_sb_mount - Target for security_sb_mount(). |
| * |
| * @dev_name: Name of device file. Maybe NULL. |
| * @path: Pointer to "struct path". |
| * @type: Name of filesystem type. Maybe NULL. |
| * @flags: Mount options. |
| * @data: Optional data. Maybe NULL. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_sb_mount(const char *dev_name, const struct path *path, |
| const char *type, unsigned long flags, void *data) |
| { |
| return tomoyo_mount_permission(dev_name, path, type, flags, data); |
| } |
| |
| /** |
| * tomoyo_sb_umount - Target for security_sb_umount(). |
| * |
| * @mnt: Pointer to "struct vfsmount". |
| * @flags: Unmount options. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_sb_umount(struct vfsmount *mnt, int flags) |
| { |
| struct path path = { .mnt = mnt, .dentry = mnt->mnt_root }; |
| return tomoyo_path_perm(TOMOYO_TYPE_UMOUNT, &path, NULL); |
| } |
| |
| /** |
| * tomoyo_sb_pivotroot - Target for security_sb_pivotroot(). |
| * |
| * @old_path: Pointer to "struct path". |
| * @new_path: Pointer to "struct path". |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_sb_pivotroot(const struct path *old_path, const struct path *new_path) |
| { |
| return tomoyo_path2_perm(TOMOYO_TYPE_PIVOT_ROOT, new_path, old_path); |
| } |
| |
| /** |
| * tomoyo_socket_listen - Check permission for listen(). |
| * |
| * @sock: Pointer to "struct socket". |
| * @backlog: Backlog parameter. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_socket_listen(struct socket *sock, int backlog) |
| { |
| return tomoyo_socket_listen_permission(sock); |
| } |
| |
| /** |
| * tomoyo_socket_connect - Check permission for connect(). |
| * |
| * @sock: Pointer to "struct socket". |
| * @addr: Pointer to "struct sockaddr". |
| * @addr_len: Size of @addr. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_socket_connect(struct socket *sock, struct sockaddr *addr, |
| int addr_len) |
| { |
| return tomoyo_socket_connect_permission(sock, addr, addr_len); |
| } |
| |
| /** |
| * tomoyo_socket_bind - Check permission for bind(). |
| * |
| * @sock: Pointer to "struct socket". |
| * @addr: Pointer to "struct sockaddr". |
| * @addr_len: Size of @addr. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_socket_bind(struct socket *sock, struct sockaddr *addr, |
| int addr_len) |
| { |
| return tomoyo_socket_bind_permission(sock, addr, addr_len); |
| } |
| |
| /** |
| * tomoyo_socket_sendmsg - Check permission for sendmsg(). |
| * |
| * @sock: Pointer to "struct socket". |
| * @msg: Pointer to "struct msghdr". |
| * @size: Size of message. |
| * |
| * Returns 0 on success, negative value otherwise. |
| */ |
| static int tomoyo_socket_sendmsg(struct socket *sock, struct msghdr *msg, |
| int size) |
| { |
| return tomoyo_socket_sendmsg_permission(sock, msg, size); |
| } |
| |
| /* |
| * tomoyo_security_ops is a "struct security_operations" which is used for |
| * registering TOMOYO. |
| */ |
| static struct security_hook_list tomoyo_hooks[] __lsm_ro_after_init = { |
| LSM_HOOK_INIT(cred_alloc_blank, tomoyo_cred_alloc_blank), |
| LSM_HOOK_INIT(cred_prepare, tomoyo_cred_prepare), |
| LSM_HOOK_INIT(cred_transfer, tomoyo_cred_transfer), |
| LSM_HOOK_INIT(cred_free, tomoyo_cred_free), |
| LSM_HOOK_INIT(bprm_set_creds, tomoyo_bprm_set_creds), |
| LSM_HOOK_INIT(bprm_check_security, tomoyo_bprm_check_security), |
| LSM_HOOK_INIT(file_fcntl, tomoyo_file_fcntl), |
| LSM_HOOK_INIT(file_open, tomoyo_file_open), |
| LSM_HOOK_INIT(path_truncate, tomoyo_path_truncate), |
| LSM_HOOK_INIT(path_unlink, tomoyo_path_unlink), |
| LSM_HOOK_INIT(path_mkdir, tomoyo_path_mkdir), |
| LSM_HOOK_INIT(path_rmdir, tomoyo_path_rmdir), |
| LSM_HOOK_INIT(path_symlink, tomoyo_path_symlink), |
| LSM_HOOK_INIT(path_mknod, tomoyo_path_mknod), |
| LSM_HOOK_INIT(path_link, tomoyo_path_link), |
| LSM_HOOK_INIT(path_rename, tomoyo_path_rename), |
| LSM_HOOK_INIT(inode_getattr, tomoyo_inode_getattr), |
| LSM_HOOK_INIT(file_ioctl, tomoyo_file_ioctl), |
| LSM_HOOK_INIT(file_ioctl_compat, tomoyo_file_ioctl), |
| LSM_HOOK_INIT(path_chmod, tomoyo_path_chmod), |
| LSM_HOOK_INIT(path_chown, tomoyo_path_chown), |
| LSM_HOOK_INIT(path_chroot, tomoyo_path_chroot), |
| LSM_HOOK_INIT(sb_mount, tomoyo_sb_mount), |
| LSM_HOOK_INIT(sb_umount, tomoyo_sb_umount), |
| LSM_HOOK_INIT(sb_pivotroot, tomoyo_sb_pivotroot), |
| LSM_HOOK_INIT(socket_bind, tomoyo_socket_bind), |
| LSM_HOOK_INIT(socket_connect, tomoyo_socket_connect), |
| LSM_HOOK_INIT(socket_listen, tomoyo_socket_listen), |
| LSM_HOOK_INIT(socket_sendmsg, tomoyo_socket_sendmsg), |
| }; |
| |
| /* Lock for GC. */ |
| DEFINE_SRCU(tomoyo_ss); |
| |
| /** |
| * tomoyo_init - Register TOMOYO Linux as a LSM module. |
| * |
| * Returns 0. |
| */ |
| static int __init tomoyo_init(void) |
| { |
| struct cred *cred = (struct cred *) current_cred(); |
| |
| if (!security_module_enable("tomoyo")) |
| return 0; |
| /* register ourselves with the security framework */ |
| security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks), "tomoyo"); |
| printk(KERN_INFO "TOMOYO Linux initialized\n"); |
| cred->security = &tomoyo_kernel_domain; |
| tomoyo_mm_init(); |
| return 0; |
| } |
| |
| security_initcall(tomoyo_init); |