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862aa05f64
freebsd/sys/kern/kern_acl.c
Christian S.J. Peron 42e7197fba Implement new world order in VFS locking for ACLs. This will remove the 
unconditional acquisition of Giant for ACL related operations. If the file
system is set as being MP safe and debug.mpsafevfs is 1, do not pickup
giant.

For any operations which require namei(9) lookups:

__acl_get_file
__acl_get_link
__acl_set_file
__acl_set_link
__acl_delete_file
__acl_delete_link
__acl_aclcheck_file
__acl_aclcheck_link

-Set the MPSAFE flag in NDINIT
-Initialize vfslocked variable using the NDHASGIANT macro

For functions which operate on fds, make sure the operations are locked:

__acl_get_fd
__acl_set_fd
__acl_delete_fd
__acl_aclcheck_fd

-Initialize vfslocked using VFS_LOCK_GIANT before we manipulate the vnode

Discussed with:	jeff
2005-09-17 22:01:14 +00:00

1037 lines
26 KiB
C
Raw Blame History

/*-
* Copyright (c) 1999-2003 Robert N. M. Watson
* All rights reserved.
*
* This software was developed by Robert Watson for the TrustedBSD Project.
*
* 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.
*/
/*
* Developed by the TrustedBSD Project.
* Support for POSIX.1e access control lists.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/kernel.h>
#include <sys/mac.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/namei.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/proc.h>
#include <sys/sysent.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/acl.h>
#include <vm/uma.h>
uma_zone_t acl_zone;
static int vacl_set_acl(struct thread *td, struct vnode *vp,
acl_type_t type, struct acl *aclp);
static int vacl_get_acl(struct thread *td, struct vnode *vp,
acl_type_t type, struct acl *aclp);
static int vacl_aclcheck(struct thread *td, struct vnode *vp,
acl_type_t type, struct acl *aclp);
/*
* Implement a version of vaccess() that understands POSIX.1e ACL semantics.
* Return 0 on success, else an errno value. Should be merged into
* vaccess() eventually.
*/
int
vaccess_acl_posix1e(enum vtype type, uid_t file_uid, gid_t file_gid,
struct acl *acl, mode_t acc_mode, struct ucred *cred, int *privused)
{
struct acl_entry *acl_other, *acl_mask;
mode_t dac_granted;
mode_t cap_granted;
mode_t acl_mask_granted;
int group_matched, i;
/*
* Look for a normal, non-privileged way to access the file/directory
* as requested. If it exists, go with that. Otherwise, attempt
* to use privileges granted via cap_granted. In some cases,
* which privileges to use may be ambiguous due to "best match",
* in which case fall back on first match for the time being.
*/
if (privused != NULL)
*privused = 0;
/*
* Determine privileges now, but don't apply until we've found
* a DAC entry that matches but has failed to allow access.
*/
#ifndef CAPABILITIES
if (suser_cred(cred, SUSER_ALLOWJAIL) == 0)
cap_granted = VALLPERM;
else
cap_granted = 0;
#else
cap_granted = 0;
if (type == VDIR) {
if ((acc_mode & VEXEC) && !cap_check(cred, NULL,
CAP_DAC_READ_SEARCH, SUSER_ALLOWJAIL))
cap_granted |= VEXEC;
} else {
if ((acc_mode & VEXEC) && !cap_check(cred, NULL,
CAP_DAC_EXECUTE, SUSER_ALLOWJAIL))
cap_granted |= VEXEC;
}
if ((acc_mode & VREAD) && !cap_check(cred, NULL, CAP_DAC_READ_SEARCH,
SUSER_ALLOWJAIL))
cap_granted |= VREAD;
if (((acc_mode & VWRITE) || (acc_mode & VAPPEND)) &&
!cap_check(cred, NULL, CAP_DAC_WRITE, SUSER_ALLOWJAIL))
cap_granted |= (VWRITE | VAPPEND);
if ((acc_mode & VADMIN) && !cap_check(cred, NULL, CAP_FOWNER,
SUSER_ALLOWJAIL))
cap_granted |= VADMIN;
#endif /* CAPABILITIES */
/*
* The owner matches if the effective uid associated with the
* credential matches that of the ACL_USER_OBJ entry. While we're
* doing the first scan, also cache the location of the ACL_MASK
* and ACL_OTHER entries, preventing some future iterations.
*/
acl_mask = acl_other = NULL;
for (i = 0; i < acl->acl_cnt; i++) {
switch (acl->acl_entry[i].ae_tag) {
case ACL_USER_OBJ:
if (file_uid != cred->cr_uid)
break;
dac_granted = 0;
dac_granted |= VADMIN;
if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
dac_granted |= VEXEC;
if (acl->acl_entry[i].ae_perm & ACL_READ)
dac_granted |= VREAD;
if (acl->acl_entry[i].ae_perm & ACL_WRITE)
dac_granted |= (VWRITE | VAPPEND);
if ((acc_mode & dac_granted) == acc_mode)
return (0);
if ((acc_mode & (dac_granted | cap_granted)) ==
acc_mode) {
if (privused != NULL)
*privused = 1;
return (0);
}
goto error;
case ACL_MASK:
acl_mask = &acl->acl_entry[i];
break;
case ACL_OTHER:
acl_other = &acl->acl_entry[i];
break;
default:
break;
}
}
/*
* An ACL_OTHER entry should always exist in a valid access
* ACL. If it doesn't, then generate a serious failure. For now,
* this means a debugging message and EPERM, but in the future
* should probably be a panic.
*/
if (acl_other == NULL) {
/*
* XXX This should never happen
*/
printf("vaccess_acl_posix1e: ACL_OTHER missing\n");
return (EPERM);
}
/*
* Checks against ACL_USER, ACL_GROUP_OBJ, and ACL_GROUP fields
* are masked by an ACL_MASK entry, if any. As such, first identify
* the ACL_MASK field, then iterate through identifying potential
* user matches, then group matches. If there is no ACL_MASK,
* assume that the mask allows all requests to succeed.
*/
if (acl_mask != NULL) {
acl_mask_granted = 0;
if (acl_mask->ae_perm & ACL_EXECUTE)
acl_mask_granted |= VEXEC;
if (acl_mask->ae_perm & ACL_READ)
acl_mask_granted |= VREAD;
if (acl_mask->ae_perm & ACL_WRITE)
acl_mask_granted |= (VWRITE | VAPPEND);
} else
acl_mask_granted = VEXEC | VREAD | VWRITE | VAPPEND;
/*
* Iterate through user ACL entries. Do checks twice, first
* without privilege, and then if a match is found but failed,
* a second time with privilege.
*/
/*
* Check ACL_USER ACL entries.
*/
for (i = 0; i < acl->acl_cnt; i++) {
switch (acl->acl_entry[i].ae_tag) {
case ACL_USER:
if (acl->acl_entry[i].ae_id != cred->cr_uid)
break;
dac_granted = 0;
if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
dac_granted |= VEXEC;
if (acl->acl_entry[i].ae_perm & ACL_READ)
dac_granted |= VREAD;
if (acl->acl_entry[i].ae_perm & ACL_WRITE)
dac_granted |= (VWRITE | VAPPEND);
dac_granted &= acl_mask_granted;
if ((acc_mode & dac_granted) == acc_mode)
return (0);
if ((acc_mode & (dac_granted | cap_granted)) !=
acc_mode)
goto error;
if (privused != NULL)
*privused = 1;
return (0);
}
}
/*
* Group match is best-match, not first-match, so find a
* "best" match. Iterate across, testing each potential group
* match. Make sure we keep track of whether we found a match
* or not, so that we know if we should try again with any
* available privilege, or if we should move on to ACL_OTHER.
*/
group_matched = 0;
for (i = 0; i < acl->acl_cnt; i++) {
switch (acl->acl_entry[i].ae_tag) {
case ACL_GROUP_OBJ:
if (!groupmember(file_gid, cred))
break;
dac_granted = 0;
if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
dac_granted |= VEXEC;
if (acl->acl_entry[i].ae_perm & ACL_READ)
dac_granted |= VREAD;
if (acl->acl_entry[i].ae_perm & ACL_WRITE)
dac_granted |= (VWRITE | VAPPEND);
dac_granted &= acl_mask_granted;
if ((acc_mode & dac_granted) == acc_mode)
return (0);
group_matched = 1;
break;
case ACL_GROUP:
if (!groupmember(acl->acl_entry[i].ae_id, cred))
break;
dac_granted = 0;
if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
dac_granted |= VEXEC;
if (acl->acl_entry[i].ae_perm & ACL_READ)
dac_granted |= VREAD;
if (acl->acl_entry[i].ae_perm & ACL_WRITE)
dac_granted |= (VWRITE | VAPPEND);
dac_granted &= acl_mask_granted;
if ((acc_mode & dac_granted) == acc_mode)
return (0);
group_matched = 1;
break;
default:
break;
}
}
if (group_matched == 1) {
/*
* There was a match, but it did not grant rights via
* pure DAC. Try again, this time with privilege.
*/
for (i = 0; i < acl->acl_cnt; i++) {
switch (acl->acl_entry[i].ae_tag) {
case ACL_GROUP_OBJ:
if (!groupmember(file_gid, cred))
break;
dac_granted = 0;
if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
dac_granted |= VEXEC;
if (acl->acl_entry[i].ae_perm & ACL_READ)
dac_granted |= VREAD;
if (acl->acl_entry[i].ae_perm & ACL_WRITE)
dac_granted |= (VWRITE | VAPPEND);
dac_granted &= acl_mask_granted;
if ((acc_mode & (dac_granted | cap_granted)) !=
acc_mode)
break;
if (privused != NULL)
*privused = 1;
return (0);
case ACL_GROUP:
if (!groupmember(acl->acl_entry[i].ae_id,
cred))
break;
dac_granted = 0;
if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
dac_granted |= VEXEC;
if (acl->acl_entry[i].ae_perm & ACL_READ)
dac_granted |= VREAD;
if (acl->acl_entry[i].ae_perm & ACL_WRITE)
dac_granted |= (VWRITE | VAPPEND);
dac_granted &= acl_mask_granted;
if ((acc_mode & (dac_granted | cap_granted)) !=
acc_mode)
break;
if (privused != NULL)
*privused = 1;
return (0);
default:
break;
}
}
/*
* Even with privilege, group membership was not sufficient.
* Return failure.
*/
goto error;
}
/*
* Fall back on ACL_OTHER. ACL_MASK is not applied to ACL_OTHER.
*/
dac_granted = 0;
if (acl_other->ae_perm & ACL_EXECUTE)
dac_granted |= VEXEC;
if (acl_other->ae_perm & ACL_READ)
dac_granted |= VREAD;
if (acl_other->ae_perm & ACL_WRITE)
dac_granted |= (VWRITE | VAPPEND);
if ((acc_mode & dac_granted) == acc_mode)
return (0);
if ((acc_mode & (dac_granted | cap_granted)) == acc_mode) {
if (privused != NULL)
*privused = 1;
return (0);
}
error:
return ((acc_mode & VADMIN) ? EPERM : EACCES);
}
/*
* For the purposes of filesystems maintaining the _OBJ entries in an
* inode with a mode_t field, this routine converts a mode_t entry
* to an acl_perm_t.
*/
acl_perm_t
acl_posix1e_mode_to_perm(acl_tag_t tag, mode_t mode)
{
acl_perm_t perm = 0;
switch(tag) {
case ACL_USER_OBJ:
if (mode & S_IXUSR)
perm |= ACL_EXECUTE;
if (mode & S_IRUSR)
perm |= ACL_READ;
if (mode & S_IWUSR)
perm |= ACL_WRITE;
return (perm);
case ACL_GROUP_OBJ:
if (mode & S_IXGRP)
perm |= ACL_EXECUTE;
if (mode & S_IRGRP)
perm |= ACL_READ;
if (mode & S_IWGRP)
perm |= ACL_WRITE;
return (perm);
case ACL_OTHER:
if (mode & S_IXOTH)
perm |= ACL_EXECUTE;
if (mode & S_IROTH)
perm |= ACL_READ;
if (mode & S_IWOTH)
perm |= ACL_WRITE;
return (perm);
default:
printf("acl_posix1e_mode_to_perm: invalid tag (%d)\n", tag);
return (0);
}
}
/*
* Given inode information (uid, gid, mode), return an acl entry of the
* appropriate type.
*/
struct acl_entry
acl_posix1e_mode_to_entry(acl_tag_t tag, uid_t uid, gid_t gid, mode_t mode)
{
struct acl_entry acl_entry;
acl_entry.ae_tag = tag;
acl_entry.ae_perm = acl_posix1e_mode_to_perm(tag, mode);
switch(tag) {
case ACL_USER_OBJ:
acl_entry.ae_id = uid;
break;
case ACL_GROUP_OBJ:
acl_entry.ae_id = gid;
break;
case ACL_OTHER:
acl_entry.ae_id = ACL_UNDEFINED_ID;
break;
default:
acl_entry.ae_id = ACL_UNDEFINED_ID;
printf("acl_posix1e_mode_to_entry: invalid tag (%d)\n", tag);
}
return (acl_entry);
}
/*
* Utility function to generate a file mode given appropriate ACL entries.
*/
mode_t
acl_posix1e_perms_to_mode(struct acl_entry *acl_user_obj_entry,
struct acl_entry *acl_group_obj_entry, struct acl_entry *acl_other_entry)
{
mode_t mode;
mode = 0;
if (acl_user_obj_entry->ae_perm & ACL_EXECUTE)
mode |= S_IXUSR;
if (acl_user_obj_entry->ae_perm & ACL_READ)
mode |= S_IRUSR;
if (acl_user_obj_entry->ae_perm & ACL_WRITE)
mode |= S_IWUSR;
if (acl_group_obj_entry->ae_perm & ACL_EXECUTE)
mode |= S_IXGRP;
if (acl_group_obj_entry->ae_perm & ACL_READ)
mode |= S_IRGRP;
if (acl_group_obj_entry->ae_perm & ACL_WRITE)
mode |= S_IWGRP;
if (acl_other_entry->ae_perm & ACL_EXECUTE)
mode |= S_IXOTH;
if (acl_other_entry->ae_perm & ACL_READ)
mode |= S_IROTH;
if (acl_other_entry->ae_perm & ACL_WRITE)
mode |= S_IWOTH;
return (mode);
}
/*
* Utility function to generate a file mode given a complete POSIX.1e
* access ACL. Note that if the ACL is improperly formed, this may
* result in a panic.
*/
mode_t
acl_posix1e_acl_to_mode(struct acl *acl)
{
struct acl_entry *acl_mask, *acl_user_obj, *acl_group_obj, *acl_other;
int i;
/*
* Find the ACL entries relevant to a POSIX permission mode.
*/
acl_user_obj = acl_group_obj = acl_other = acl_mask = NULL;
for (i = 0; i < acl->acl_cnt; i++) {
switch (acl->acl_entry[i].ae_tag) {
case ACL_USER_OBJ:
acl_user_obj = &acl->acl_entry[i];
break;
case ACL_GROUP_OBJ:
acl_group_obj = &acl->acl_entry[i];
break;
case ACL_OTHER:
acl_other = &acl->acl_entry[i];
break;
case ACL_MASK:
acl_mask = &acl->acl_entry[i];
break;
case ACL_USER:
case ACL_GROUP:
break;
default:
panic("acl_posix1e_acl_to_mode: bad ae_tag");
}
}
if (acl_user_obj == NULL || acl_group_obj == NULL || acl_other == NULL)
panic("acl_posix1e_acl_to_mode: missing base ae_tags");
/*
* POSIX.1e specifies that if there is an ACL_MASK entry, we replace
* the mode "group" bits with its permissions. If there isn't, we
* use the ACL_GROUP_OBJ permissions.
*/
if (acl_mask != NULL)
return (acl_posix1e_perms_to_mode(acl_user_obj, acl_mask,
acl_other));
else
return (acl_posix1e_perms_to_mode(acl_user_obj, acl_group_obj,
acl_other));
}
/*
* Perform a syntactic check of the ACL, sufficient to allow an
* implementing filesystem to determine if it should accept this and
* rely on the POSIX.1e ACL properties.
*/
int
acl_posix1e_check(struct acl *acl)
{
int num_acl_user_obj, num_acl_user, num_acl_group_obj, num_acl_group;
int num_acl_mask, num_acl_other, i;
/*
* Verify that the number of entries does not exceed the maximum
* defined for acl_t.
* Verify that the correct number of various sorts of ae_tags are
* present:
* Exactly one ACL_USER_OBJ
* Exactly one ACL_GROUP_OBJ
* Exactly one ACL_OTHER
* If any ACL_USER or ACL_GROUP entries appear, then exactly one
* ACL_MASK entry must also appear.
* Verify that all ae_perm entries are in ACL_PERM_BITS.
* Verify all ae_tag entries are understood by this implementation.
* Note: Does not check for uniqueness of qualifier (ae_id) field.
*/
num_acl_user_obj = num_acl_user = num_acl_group_obj = num_acl_group =
num_acl_mask = num_acl_other = 0;
if (acl->acl_cnt > ACL_MAX_ENTRIES || acl->acl_cnt < 0)
return (EINVAL);
for (i = 0; i < acl->acl_cnt; i++) {
/*
* Check for a valid tag.
*/
switch(acl->acl_entry[i].ae_tag) {
case ACL_USER_OBJ:
acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
return (EINVAL);
num_acl_user_obj++;
break;
case ACL_GROUP_OBJ:
acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
return (EINVAL);
num_acl_group_obj++;
break;
case ACL_USER:
if (acl->acl_entry[i].ae_id == ACL_UNDEFINED_ID)
return (EINVAL);
num_acl_user++;
break;
case ACL_GROUP:
if (acl->acl_entry[i].ae_id == ACL_UNDEFINED_ID)
return (EINVAL);
num_acl_group++;
break;
case ACL_OTHER:
acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
return (EINVAL);
num_acl_other++;
break;
case ACL_MASK:
acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
return (EINVAL);
num_acl_mask++;
break;
default:
return (EINVAL);
}
/*
* Check for valid perm entries.
*/
if ((acl->acl_entry[i].ae_perm | ACL_PERM_BITS) !=
ACL_PERM_BITS)
return (EINVAL);
}
if ((num_acl_user_obj != 1) || (num_acl_group_obj != 1) ||
(num_acl_other != 1) || (num_acl_mask != 0 && num_acl_mask != 1))
return (EINVAL);
if (((num_acl_group != 0) || (num_acl_user != 0)) &&
(num_acl_mask != 1))
return (EINVAL);
return (0);
}
/*
* Given a requested mode for a new object, and a default ACL, combine
* the two to produce a new mode. Be careful not to clear any bits that
* aren't intended to be affected by the POSIX.1e ACL. Eventually,
* this might also take the cmask as an argument, if we push that down
* into per-filesystem-code.
*/
mode_t
acl_posix1e_newfilemode(mode_t cmode, struct acl *dacl)
{
mode_t mode;
mode = cmode;
/*
* The current composition policy is that a permission bit must
* be set in *both* the ACL and the requested creation mode for
* it to appear in the resulting mode/ACL. First clear any
* possibly effected bits, then reconstruct.
*/
mode &= ACL_PRESERVE_MASK;
mode |= (ACL_OVERRIDE_MASK & cmode & acl_posix1e_acl_to_mode(dacl));
return (mode);
}
/*
* 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 thread *td, struct vnode *vp, acl_type_t type,
struct acl *aclp)
{
struct acl inkernacl;
struct mount *mp;
int error;
error = copyin(aclp, &inkernacl, sizeof(struct acl));
if (error)
return(error);
error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
if (error != 0)
return (error);
VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
#ifdef MAC
error = mac_check_vnode_setacl(td->td_ucred, vp, type, &inkernacl);
if (error != 0)
goto out;
#endif
error = VOP_SETACL(vp, type, &inkernacl, td->td_ucred, td);
#ifdef MAC
out:
#endif
VOP_UNLOCK(vp, 0, td);
vn_finished_write(mp);
return(error);
}
/*
* Given a vnode, get its ACL.
*/
static int
vacl_get_acl(struct thread *td, struct vnode *vp, acl_type_t type,
struct acl *aclp)
{
struct acl inkernelacl;
int error;
VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
#ifdef MAC
error = mac_check_vnode_getacl(td->td_ucred, vp, type);
if (error != 0)
goto out;
#endif
error = VOP_GETACL(vp, type, &inkernelacl, td->td_ucred, td);
#ifdef MAC
out:
#endif
VOP_UNLOCK(vp, 0, td);
if (error == 0)
error = copyout(&inkernelacl, aclp, sizeof(struct acl));
return (error);
}
/*
* Given a vnode, delete its ACL.
*/
static int
vacl_delete(struct thread *td, struct vnode *vp, acl_type_t type)
{
struct mount *mp;
int error;
error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
if (error)
return (error);
VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
#ifdef MAC
error = mac_check_vnode_deleteacl(td->td_ucred, vp, type);
if (error)
goto out;
#endif
error = VOP_SETACL(vp, type, 0, td->td_ucred, td);
#ifdef MAC
out:
#endif
VOP_UNLOCK(vp, 0, td);
vn_finished_write(mp);
return (error);
}
/*
* Given a vnode, check whether an ACL is appropriate for it
*/
static int
vacl_aclcheck(struct thread *td, 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, td->td_ucred, td);
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
*
* MPSAFE
*/
int
__acl_get_file(struct thread *td, struct __acl_get_file_args *uap)
{
struct nameidata nd;
int vfslocked, error;
NDINIT(&nd, LOOKUP, MPSAFE|FOLLOW, UIO_USERSPACE, uap->path, td);
error = namei(&nd);
vfslocked = NDHASGIANT(&nd);
if (error == 0) {
error = vacl_get_acl(td, nd.ni_vp, uap->type, uap->aclp);
NDFREE(&nd, 0);
}
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Given a file path, get an ACL for it; don't follow links.
*
* MPSAFE
*/
int
__acl_get_link(struct thread *td, struct __acl_get_link_args *uap)
{
struct nameidata nd;
int vfslocked, error;
NDINIT(&nd, LOOKUP, MPSAFE|NOFOLLOW, UIO_USERSPACE, uap->path, td);
error = namei(&nd);
vfslocked = NDHASGIANT(&nd);
if (error == 0) {
error = vacl_get_acl(td, nd.ni_vp, uap->type, uap->aclp);
NDFREE(&nd, 0);
}
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Given a file path, set an ACL for it
*
* MPSAFE
*/
int
__acl_set_file(struct thread *td, struct __acl_set_file_args *uap)
{
struct nameidata nd;
int vfslocked, error;
NDINIT(&nd, LOOKUP, MPSAFE|FOLLOW, UIO_USERSPACE, uap->path, td);
error = namei(&nd);
vfslocked = NDHASGIANT(&nd);
if (error == 0) {
error = vacl_set_acl(td, nd.ni_vp, uap->type, uap->aclp);
NDFREE(&nd, 0);
}
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Given a file path, set an ACL for it; don't follow links.
*
* MPSAFE
*/
int
__acl_set_link(struct thread *td, struct __acl_set_link_args *uap)
{
struct nameidata nd;
int vfslocked, error;
NDINIT(&nd, LOOKUP, MPSAFE|NOFOLLOW, UIO_USERSPACE, uap->path, td);
error = namei(&nd);
vfslocked = NDHASGIANT(&nd);
if (error == 0) {
error = vacl_set_acl(td, nd.ni_vp, uap->type, uap->aclp);
NDFREE(&nd, 0);
}
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Given a file descriptor, get an ACL for it
*
* MPSAFE
*/
int
__acl_get_fd(struct thread *td, struct __acl_get_fd_args *uap)
{
struct file *fp;
int vfslocked, error;
error = getvnode(td->td_proc->p_fd, uap->filedes, &fp);
if (error == 0) {
vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
error = vacl_get_acl(td, fp->f_vnode, uap->type, uap->aclp);
fdrop(fp, td);
VFS_UNLOCK_GIANT(vfslocked);
}
return (error);
}
/*
* Given a file descriptor, set an ACL for it
*
* MPSAFE
*/
int
__acl_set_fd(struct thread *td, struct __acl_set_fd_args *uap)
{
struct file *fp;
int vfslocked, error;
error = getvnode(td->td_proc->p_fd, uap->filedes, &fp);
if (error == 0) {
vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
error = vacl_set_acl(td, fp->f_vnode, uap->type, uap->aclp);
fdrop(fp, td);
VFS_UNLOCK_GIANT(vfslocked);
}
return (error);
}
/*
* Given a file path, delete an ACL from it.
*
* MPSAFE
*/
int
__acl_delete_file(struct thread *td, struct __acl_delete_file_args *uap)
{
struct nameidata nd;
int vfslocked, error;
NDINIT(&nd, LOOKUP, MPSAFE|FOLLOW, UIO_USERSPACE, uap->path, td);
error = namei(&nd);
vfslocked = NDHASGIANT(&nd);
if (error == 0) {
error = vacl_delete(td, nd.ni_vp, uap->type);
NDFREE(&nd, 0);
}
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Given a file path, delete an ACL from it; don't follow links.
*
* MPSAFE
*/
int
__acl_delete_link(struct thread *td, struct __acl_delete_link_args *uap)
{
struct nameidata nd;
int vfslocked, error;
NDINIT(&nd, LOOKUP, MPSAFE|NOFOLLOW, UIO_USERSPACE, uap->path, td);
error = namei(&nd);
vfslocked = NDHASGIANT(&nd);
if (error == 0) {
error = vacl_delete(td, nd.ni_vp, uap->type);
NDFREE(&nd, 0);
}
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Given a file path, delete an ACL from it.
*
* MPSAFE
*/
int
__acl_delete_fd(struct thread *td, struct __acl_delete_fd_args *uap)
{
struct file *fp;
int vfslocked, error;
error = getvnode(td->td_proc->p_fd, uap->filedes, &fp);
if (error == 0) {
vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
error = vacl_delete(td, fp->f_vnode, uap->type);
fdrop(fp, td);
VFS_UNLOCK_GIANT(vfslocked);
}
return (error);
}
/*
* Given a file path, check an ACL for it
*
* MPSAFE
*/
int
__acl_aclcheck_file(struct thread *td, struct __acl_aclcheck_file_args *uap)
{
struct nameidata nd;
int vfslocked, error;
NDINIT(&nd, LOOKUP, MPSAFE|FOLLOW, UIO_USERSPACE, uap->path, td);
error = namei(&nd);
vfslocked = NDHASGIANT(&nd);
if (error == 0) {
error = vacl_aclcheck(td, nd.ni_vp, uap->type, uap->aclp);
NDFREE(&nd, 0);
}
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Given a file path, check an ACL for it; don't follow links.
*
* MPSAFE
*/
int
__acl_aclcheck_link(struct thread *td, struct __acl_aclcheck_link_args *uap)
{
struct nameidata nd;
int vfslocked, error;
NDINIT(&nd, LOOKUP, MPSAFE|NOFOLLOW, UIO_USERSPACE, uap->path, td);
error = namei(&nd);
vfslocked = NDHASGIANT(&nd);
if (error == 0) {
error = vacl_aclcheck(td, nd.ni_vp, uap->type, uap->aclp);
NDFREE(&nd, 0);
}
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Given a file descriptor, check an ACL for it
*
* MPSAFE
*/
int
__acl_aclcheck_fd(struct thread *td, struct __acl_aclcheck_fd_args *uap)
{
struct file *fp;
int vfslocked, error;
error = getvnode(td->td_proc->p_fd, uap->filedes, &fp);
if (error == 0) {
vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
error = vacl_aclcheck(td, fp->f_vnode, uap->type, uap->aclp);
fdrop(fp, td);
VFS_UNLOCK_GIANT(vfslocked);
}
return (error);
}
/* ARGUSED */
static void
aclinit(void *dummy __unused)
{
acl_zone = uma_zcreate("ACL UMA zone", sizeof(struct acl),
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
}
SYSINIT(acls, SI_SUB_ACL, SI_ORDER_FIRST, aclinit, NULL)
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