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/*-
* Copyright (c) 1999, 2000 Robert N. M. Watson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* Generic routines to support file system ACLs, at a syntactic level
* Semantics are the responsibility of the underlying file system
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/lock.h>
#include <sys/namei.h>
#include <sys/file.h>
#include <sys/proc.h>
#include <sys/sysent.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/acl.h>
static MALLOC_DEFINE(M_ACL, "acl", "access control list");
static int vacl_set_acl(struct proc *p, struct vnode *vp, acl_type_t type,
struct acl *aclp);
static int vacl_get_acl(struct proc *p, struct vnode *vp, acl_type_t type,
struct acl *aclp);
static int vacl_aclcheck(struct proc *p, struct vnode *vp, acl_type_t type,
struct acl *aclp);
/*
* These calls wrap the real vnode operations, and are called by the
* syscall code once the syscall has converted the path or file
* descriptor to a vnode (unlocked). The aclp pointer is assumed
* still to point to userland, so this should not be consumed within
* the kernel except by syscall code. Other code should directly
* invoke VOP_{SET,GET}ACL.
*/
/*
* Given a vnode, set its ACL.
*/
static int
vacl_set_acl(struct proc *p, struct vnode *vp, acl_type_t type,
struct acl *aclp)
{
struct acl inkernacl;
int error;
error = copyin(aclp, &inkernacl, sizeof(struct acl));
if (error)
return(error);
VOP_LEASE(vp, p, p->p_ucred, LEASE_WRITE);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
error = VOP_SETACL(vp, type, &inkernacl, p->p_ucred, p);
VOP_UNLOCK(vp, 0, p);
return(error);
}
/*
* Given a vnode, get its ACL.
*/
static int
vacl_get_acl(struct proc *p, struct vnode *vp, acl_type_t type,
struct acl *aclp)
{
struct acl inkernelacl;
int error;
error = VOP_GETACL(vp, type, &inkernelacl, p->p_ucred, p);
if (error == 0)
error = copyout(&inkernelacl, aclp, sizeof(struct acl));
return (error);
}
/*
* Given a vnode, delete its ACL.
*/
static int
vacl_delete(struct proc *p, struct vnode *vp, acl_type_t type)
{
int error;
VOP_LEASE(vp, p, p->p_ucred, LEASE_WRITE);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
error = VOP_SETACL(vp, ACL_TYPE_DEFAULT, 0, p->p_ucred, p);
VOP_UNLOCK(vp, 0, p);
return (error);
}
/*
* Given a vnode, check whether an ACL is appropriate for it
*/
static int
vacl_aclcheck(struct proc *p, struct vnode *vp, acl_type_t type,
struct acl *aclp)
{
struct acl inkernelacl;
int error;
error = copyin(aclp, &inkernelacl, sizeof(struct acl));
if (error)
return(error);
error = VOP_ACLCHECK(vp, type, &inkernelacl, p->p_ucred, p);
return (error);
}
/*
* syscalls -- convert the path/fd to a vnode, and call vacl_whatever.
* Don't need to lock, as the vacl_ code will get/release any locks
* required.
*/
/*
* Given a file path, get an ACL for it
*/
int
__acl_get_file(struct proc *p, struct __acl_get_file_args *uap)
{
struct nameidata nd;
int error;
/* what flags are required here -- possible not LOCKLEAF? */
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), p);
error = namei(&nd);
if (error)
return(error);
error = vacl_get_acl(p, nd.ni_vp, SCARG(uap, type), SCARG(uap, aclp));
NDFREE(&nd, 0);
return (error);
}
/*
* Given a file path, set an ACL for it
*/
int
__acl_set_file(struct proc *p, struct __acl_set_file_args *uap)
{
struct nameidata nd;
int error;
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), p);
error = namei(&nd);
if (error)
return(error);
error = vacl_set_acl(p, nd.ni_vp, SCARG(uap, type), SCARG(uap, aclp));
NDFREE(&nd, 0);
return (error);
}
/*
* Given a file descriptor, get an ACL for it
*/
int
__acl_get_fd(struct proc *p, struct __acl_get_fd_args *uap)
{
struct file *fp;
int error;
error = getvnode(p->p_fd, SCARG(uap, filedes), &fp);
if (error)
return(error);
return vacl_get_acl(p, (struct vnode *)fp->f_data, SCARG(uap, type),
SCARG(uap, aclp));
}
/*
* Given a file descriptor, set an ACL for it
*/
int
__acl_set_fd(struct proc *p, struct __acl_set_fd_args *uap)
{
struct file *fp;
int error;
error = getvnode(p->p_fd, SCARG(uap, filedes), &fp);
if (error)
return(error);
return vacl_set_acl(p, (struct vnode *)fp->f_data, SCARG(uap, type),
SCARG(uap, aclp));
}
/*
* Given a file path, delete an ACL from it.
*/
int
__acl_delete_file(struct proc *p, struct __acl_delete_file_args *uap)
{
struct nameidata nd;
int error;
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), p);
error = namei(&nd);
if (error)
return(error);
error = vacl_delete(p, nd.ni_vp, SCARG(uap, type));
NDFREE(&nd, 0);
return (error);
}
/*
* Given a file path, delete an ACL from it.
*/
int
__acl_delete_fd(struct proc *p, struct __acl_delete_fd_args *uap)
{
struct file *fp;
int error;
error = getvnode(p->p_fd, SCARG(uap, filedes), &fp);
if (error)
return(error);
error = vacl_delete(p, (struct vnode *)fp->f_data, SCARG(uap, type));
return (error);
}
/*
* Given a file path, check an ACL for it
*/
int
__acl_aclcheck_file(struct proc *p, struct __acl_aclcheck_file_args *uap)
{
struct nameidata nd;
int error;
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), p);
error = namei(&nd);
if (error)
return(error);
error = vacl_aclcheck(p, nd.ni_vp, SCARG(uap, type), SCARG(uap, aclp));
NDFREE(&nd, 0);
return (error);
}
/*
* Given a file descriptor, check an ACL for it
*/
int
__acl_aclcheck_fd(struct proc *p, struct __acl_aclcheck_fd_args *uap)
{
struct file *fp;
int error;
error = getvnode(p->p_fd, SCARG(uap, filedes), &fp);
if (error)
return(error);
return vacl_aclcheck(p, (struct vnode *)fp->f_data, SCARG(uap, type),
SCARG(uap, aclp));
}
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