2 * Copyright (c) 1999-2006 Robert N. M. Watson
5 * This software was developed by Robert Watson for the TrustedBSD Project.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * Developed by the TrustedBSD Project.
31 * ACL system calls and other functions common across different ACL types.
32 * Type-specific routines go into subr_acl_<type>.c.
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/sysproto.h>
41 #include <sys/capability.h>
42 #include <sys/fcntl.h>
43 #include <sys/kernel.h>
44 #include <sys/malloc.h>
45 #include <sys/mount.h>
46 #include <sys/vnode.h>
48 #include <sys/mutex.h>
49 #include <sys/namei.h>
51 #include <sys/filedesc.h>
53 #include <sys/sysent.h>
56 #include <security/mac/mac_framework.h>
58 CTASSERT(ACL_MAX_ENTRIES >= OLDACL_MAX_ENTRIES);
60 MALLOC_DEFINE(M_ACL, "acl", "Access Control Lists");
62 static int vacl_set_acl(struct thread *td, struct vnode *vp,
63 acl_type_t type, struct acl *aclp);
64 static int vacl_get_acl(struct thread *td, struct vnode *vp,
65 acl_type_t type, struct acl *aclp);
66 static int vacl_aclcheck(struct thread *td, struct vnode *vp,
67 acl_type_t type, struct acl *aclp);
70 acl_copy_oldacl_into_acl(const struct oldacl *source, struct acl *dest)
74 if (source->acl_cnt < 0 || source->acl_cnt > OLDACL_MAX_ENTRIES)
77 bzero(dest, sizeof(*dest));
79 dest->acl_cnt = source->acl_cnt;
80 dest->acl_maxcnt = ACL_MAX_ENTRIES;
82 for (i = 0; i < dest->acl_cnt; i++) {
83 dest->acl_entry[i].ae_tag = source->acl_entry[i].ae_tag;
84 dest->acl_entry[i].ae_id = source->acl_entry[i].ae_id;
85 dest->acl_entry[i].ae_perm = source->acl_entry[i].ae_perm;
92 acl_copy_acl_into_oldacl(const struct acl *source, struct oldacl *dest)
96 if (source->acl_cnt > OLDACL_MAX_ENTRIES)
99 bzero(dest, sizeof(*dest));
101 dest->acl_cnt = source->acl_cnt;
103 for (i = 0; i < dest->acl_cnt; i++) {
104 dest->acl_entry[i].ae_tag = source->acl_entry[i].ae_tag;
105 dest->acl_entry[i].ae_id = source->acl_entry[i].ae_id;
106 dest->acl_entry[i].ae_perm = source->acl_entry[i].ae_perm;
113 * At one time, "struct ACL" was extended in order to add support for NFSv4
114 * ACLs. Instead of creating compatibility versions of all the ACL-related
115 * syscalls, they were left intact. It's possible to find out what the code
116 * calling these syscalls (libc) expects basing on "type" argument - if it's
117 * either ACL_TYPE_ACCESS_OLD or ACL_TYPE_DEFAULT_OLD (which previously were
118 * known as ACL_TYPE_ACCESS and ACL_TYPE_DEFAULT), then it's the "struct
119 * oldacl". If it's something else, then it's the new "struct acl". In the
120 * latter case, the routines below just copyin/copyout the contents. In the
121 * former case, they copyin the "struct oldacl" and convert it to the new
125 acl_copyin(void *user_acl, struct acl *kernel_acl, acl_type_t type)
131 case ACL_TYPE_ACCESS_OLD:
132 case ACL_TYPE_DEFAULT_OLD:
133 error = copyin(user_acl, &old, sizeof(old));
136 acl_copy_oldacl_into_acl(&old, kernel_acl);
140 error = copyin(user_acl, kernel_acl, sizeof(*kernel_acl));
141 if (kernel_acl->acl_maxcnt != ACL_MAX_ENTRIES)
149 acl_copyout(struct acl *kernel_acl, void *user_acl, acl_type_t type)
155 case ACL_TYPE_ACCESS_OLD:
156 case ACL_TYPE_DEFAULT_OLD:
157 error = acl_copy_acl_into_oldacl(kernel_acl, &old);
161 error = copyout(&old, user_acl, sizeof(old));
165 if (fuword32((char *)user_acl +
166 offsetof(struct acl, acl_maxcnt)) != ACL_MAX_ENTRIES)
169 error = copyout(kernel_acl, user_acl, sizeof(*kernel_acl));
176 * Convert "old" type - ACL_TYPE_{ACCESS,DEFAULT}_OLD - into its "new"
177 * counterpart. It's required for old (pre-NFSv4 ACLs) libc to work
178 * with new kernel. Fixing 'type' for old binaries with new libc
179 * is being done in lib/libc/posix1e/acl_support.c:_acl_type_unold().
182 acl_type_unold(int type)
185 case ACL_TYPE_ACCESS_OLD:
186 return (ACL_TYPE_ACCESS);
188 case ACL_TYPE_DEFAULT_OLD:
189 return (ACL_TYPE_DEFAULT);
197 * These calls wrap the real vnode operations, and are called by the syscall
198 * code once the syscall has converted the path or file descriptor to a vnode
199 * (unlocked). The aclp pointer is assumed still to point to userland, so
200 * this should not be consumed within the kernel except by syscall code.
201 * Other code should directly invoke VOP_{SET,GET}ACL.
205 * Given a vnode, set its ACL.
208 vacl_set_acl(struct thread *td, struct vnode *vp, acl_type_t type,
211 struct acl *inkernelacl;
215 inkernelacl = acl_alloc(M_WAITOK);
216 error = acl_copyin(aclp, inkernelacl, type);
219 error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
222 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
224 error = mac_vnode_check_setacl(td->td_ucred, vp, type, inkernelacl);
228 error = VOP_SETACL(vp, acl_type_unold(type), inkernelacl,
234 vn_finished_write(mp);
236 acl_free(inkernelacl);
241 * Given a vnode, get its ACL.
244 vacl_get_acl(struct thread *td, struct vnode *vp, acl_type_t type,
247 struct acl *inkernelacl;
250 inkernelacl = acl_alloc(M_WAITOK);
251 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
253 error = mac_vnode_check_getacl(td->td_ucred, vp, type);
257 error = VOP_GETACL(vp, acl_type_unold(type), inkernelacl,
265 error = acl_copyout(inkernelacl, aclp, type);
266 acl_free(inkernelacl);
271 * Given a vnode, delete its ACL.
274 vacl_delete(struct thread *td, struct vnode *vp, acl_type_t type)
279 error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
282 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
284 error = mac_vnode_check_deleteacl(td->td_ucred, vp, type);
288 error = VOP_SETACL(vp, acl_type_unold(type), 0, td->td_ucred, td);
293 vn_finished_write(mp);
298 * Given a vnode, check whether an ACL is appropriate for it
301 vacl_aclcheck(struct thread *td, struct vnode *vp, acl_type_t type,
304 struct acl *inkernelacl;
307 inkernelacl = acl_alloc(M_WAITOK);
308 error = acl_copyin(aclp, inkernelacl, type);
311 error = VOP_ACLCHECK(vp, acl_type_unold(type), inkernelacl,
314 acl_free(inkernelacl);
319 * syscalls -- convert the path/fd to a vnode, and call vacl_whatever. Don't
320 * need to lock, as the vacl_ code will get/release any locks required.
324 * Given a file path, get an ACL for it
327 sys___acl_get_file(struct thread *td, struct __acl_get_file_args *uap)
330 int vfslocked, error;
332 NDINIT(&nd, LOOKUP, MPSAFE|FOLLOW, UIO_USERSPACE, uap->path, td);
334 vfslocked = NDHASGIANT(&nd);
336 error = vacl_get_acl(td, nd.ni_vp, uap->type, uap->aclp);
339 VFS_UNLOCK_GIANT(vfslocked);
344 * Given a file path, get an ACL for it; don't follow links.
347 sys___acl_get_link(struct thread *td, struct __acl_get_link_args *uap)
350 int vfslocked, error;
352 NDINIT(&nd, LOOKUP, MPSAFE|NOFOLLOW, UIO_USERSPACE, uap->path, td);
354 vfslocked = NDHASGIANT(&nd);
356 error = vacl_get_acl(td, nd.ni_vp, uap->type, uap->aclp);
359 VFS_UNLOCK_GIANT(vfslocked);
364 * Given a file path, set an ACL for it.
367 sys___acl_set_file(struct thread *td, struct __acl_set_file_args *uap)
370 int vfslocked, error;
372 NDINIT(&nd, LOOKUP, MPSAFE|FOLLOW, UIO_USERSPACE, uap->path, td);
374 vfslocked = NDHASGIANT(&nd);
376 error = vacl_set_acl(td, nd.ni_vp, uap->type, uap->aclp);
379 VFS_UNLOCK_GIANT(vfslocked);
384 * Given a file path, set an ACL for it; don't follow links.
387 sys___acl_set_link(struct thread *td, struct __acl_set_link_args *uap)
390 int vfslocked, error;
392 NDINIT(&nd, LOOKUP, MPSAFE|NOFOLLOW, UIO_USERSPACE, uap->path, td);
394 vfslocked = NDHASGIANT(&nd);
396 error = vacl_set_acl(td, nd.ni_vp, uap->type, uap->aclp);
399 VFS_UNLOCK_GIANT(vfslocked);
404 * Given a file descriptor, get an ACL for it.
407 sys___acl_get_fd(struct thread *td, struct __acl_get_fd_args *uap)
410 int vfslocked, error;
412 error = getvnode(td->td_proc->p_fd, uap->filedes, CAP_ACL_GET, &fp);
414 vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
415 error = vacl_get_acl(td, fp->f_vnode, uap->type, uap->aclp);
417 VFS_UNLOCK_GIANT(vfslocked);
423 * Given a file descriptor, set an ACL for it.
426 sys___acl_set_fd(struct thread *td, struct __acl_set_fd_args *uap)
429 int vfslocked, error;
431 error = getvnode(td->td_proc->p_fd, uap->filedes, CAP_ACL_SET, &fp);
433 vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
434 error = vacl_set_acl(td, fp->f_vnode, uap->type, uap->aclp);
436 VFS_UNLOCK_GIANT(vfslocked);
442 * Given a file path, delete an ACL from it.
445 sys___acl_delete_file(struct thread *td, struct __acl_delete_file_args *uap)
448 int vfslocked, error;
450 NDINIT(&nd, LOOKUP, MPSAFE|FOLLOW, UIO_USERSPACE, uap->path, td);
452 vfslocked = NDHASGIANT(&nd);
454 error = vacl_delete(td, nd.ni_vp, uap->type);
457 VFS_UNLOCK_GIANT(vfslocked);
462 * Given a file path, delete an ACL from it; don't follow links.
465 sys___acl_delete_link(struct thread *td, struct __acl_delete_link_args *uap)
468 int vfslocked, error;
470 NDINIT(&nd, LOOKUP, MPSAFE|NOFOLLOW, UIO_USERSPACE, uap->path, td);
472 vfslocked = NDHASGIANT(&nd);
474 error = vacl_delete(td, nd.ni_vp, uap->type);
477 VFS_UNLOCK_GIANT(vfslocked);
482 * Given a file path, delete an ACL from it.
485 sys___acl_delete_fd(struct thread *td, struct __acl_delete_fd_args *uap)
488 int vfslocked, error;
490 error = getvnode(td->td_proc->p_fd, uap->filedes, CAP_ACL_DELETE,
493 vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
494 error = vacl_delete(td, fp->f_vnode, uap->type);
496 VFS_UNLOCK_GIANT(vfslocked);
502 * Given a file path, check an ACL for it.
505 sys___acl_aclcheck_file(struct thread *td, struct __acl_aclcheck_file_args *uap)
508 int vfslocked, error;
510 NDINIT(&nd, LOOKUP, MPSAFE|FOLLOW, UIO_USERSPACE, uap->path, td);
512 vfslocked = NDHASGIANT(&nd);
514 error = vacl_aclcheck(td, nd.ni_vp, uap->type, uap->aclp);
517 VFS_UNLOCK_GIANT(vfslocked);
522 * Given a file path, check an ACL for it; don't follow links.
525 sys___acl_aclcheck_link(struct thread *td, struct __acl_aclcheck_link_args *uap)
528 int vfslocked, error;
530 NDINIT(&nd, LOOKUP, MPSAFE|NOFOLLOW, UIO_USERSPACE, uap->path, td);
532 vfslocked = NDHASGIANT(&nd);
534 error = vacl_aclcheck(td, nd.ni_vp, uap->type, uap->aclp);
537 VFS_UNLOCK_GIANT(vfslocked);
542 * Given a file descriptor, check an ACL for it.
545 sys___acl_aclcheck_fd(struct thread *td, struct __acl_aclcheck_fd_args *uap)
548 int vfslocked, error;
550 error = getvnode(td->td_proc->p_fd, uap->filedes, CAP_ACL_CHECK,
553 vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
554 error = vacl_aclcheck(td, fp->f_vnode, uap->type, uap->aclp);
556 VFS_UNLOCK_GIANT(vfslocked);
566 aclp = malloc(sizeof(*aclp), M_ACL, flags);
567 aclp->acl_maxcnt = ACL_MAX_ENTRIES;
573 acl_free(struct acl *aclp)