/*
* security/tomoyo/tomoyo.c
*
* Copyright (C) 2005-2011 NTT DATA CORPORATION
*/
#include <linux/security.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)
{
int rc;
rc = cap_bprm_set_creds(bprm);
if (rc)
return rc;
/*
* Do only if this function is called for the first time of an execve
* operation.
*/
if (bprm->cred_prepared)
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(struct vfsmount *mnt, struct dentry *dentry)
{
struct path path = { mnt, dentry };
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(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(struct path *parent, struct dentry *dentry)
{
struct path path = { parent->mnt, 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(struct path *parent, struct dentry *dentry,
umode_t mode)
{
struct path path = { parent->mnt, 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(struct path *parent, struct dentry *dentry)
{
struct path path = { parent->mnt, 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(struct path *parent, struct dentry *dentry,
const char *old_name)
{
struct path path = { parent->mnt, 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(struct path *parent, struct dentry *dentry,
umode_t mode, unsigned int dev)
{
struct path path = { parent->mnt, 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, struct path *new_dir,
struct dentry *new_dentry)
{
struct path path1 = { new_dir->mnt, old_dentry };
struct path path2 = { new_dir->mnt, 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(struct path *old_parent,
struct dentry *old_dentry,
struct path *new_parent,
struct dentry *new_dentry)
{
struct path path1 = { old_parent->mnt, old_dentry };
struct path path2 = { new_parent->mnt, 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(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(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(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, 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->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(struct path *old_path, 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_operations tomoyo_security_ops = {
.name = "tomoyo",
.cred_alloc_blank = tomoyo_cred_alloc_blank,
.cred_prepare = tomoyo_cred_prepare,
.cred_transfer = tomoyo_cred_transfer,
.cred_free = tomoyo_cred_free,
.bprm_set_creds = tomoyo_bprm_set_creds,
.bprm_check_security = tomoyo_bprm_check_security,
.file_fcntl = tomoyo_file_fcntl,
.file_open = tomoyo_file_open,
.path_truncate = tomoyo_path_truncate,
.path_unlink = tomoyo_path_unlink,
.path_mkdir = tomoyo_path_mkdir,
.path_rmdir = tomoyo_path_rmdir,
.path_symlink = tomoyo_path_symlink,
.path_mknod = tomoyo_path_mknod,
.path_link = tomoyo_path_link,
.path_rename = tomoyo_path_rename,
.inode_getattr = tomoyo_inode_getattr,
.file_ioctl = tomoyo_file_ioctl,
.path_chmod = tomoyo_path_chmod,
.path_chown = tomoyo_path_chown,
.path_chroot = tomoyo_path_chroot,
.sb_mount = tomoyo_sb_mount,
.sb_umount = tomoyo_sb_umount,
.sb_pivotroot = tomoyo_sb_pivotroot,
.socket_bind = tomoyo_socket_bind,
.socket_connect = tomoyo_socket_connect,
.socket_listen = tomoyo_socket_listen,
.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_security_ops))
return 0;
/* register ourselves with the security framework */
if (register_security(&tomoyo_security_ops))
panic("Failure registering TOMOYO Linux");
printk(KERN_INFO "TOMOYO Linux initialized\n");
cred->security = &tomoyo_kernel_domain;
tomoyo_mm_init();
return 0;
}
security_initcall(tomoyo_init);
