summaryrefslogtreecommitdiff
path: root/ANDROID_3.4.5/fs/posix_acl.c
diff options
context:
space:
mode:
Diffstat (limited to 'ANDROID_3.4.5/fs/posix_acl.c')
-rw-r--r--ANDROID_3.4.5/fs/posix_acl.c420
1 files changed, 0 insertions, 420 deletions
diff --git a/ANDROID_3.4.5/fs/posix_acl.c b/ANDROID_3.4.5/fs/posix_acl.c
deleted file mode 100644
index 5e325a42..00000000
--- a/ANDROID_3.4.5/fs/posix_acl.c
+++ /dev/null
@@ -1,420 +0,0 @@
-/*
- * linux/fs/posix_acl.c
- *
- * Copyright (C) 2002 by Andreas Gruenbacher <a.gruenbacher@computer.org>
- *
- * Fixes from William Schumacher incorporated on 15 March 2001.
- * (Reported by Charles Bertsch, <CBertsch@microtest.com>).
- */
-
-/*
- * This file contains generic functions for manipulating
- * POSIX 1003.1e draft standard 17 ACLs.
- */
-
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/atomic.h>
-#include <linux/fs.h>
-#include <linux/sched.h>
-#include <linux/posix_acl.h>
-#include <linux/export.h>
-
-#include <linux/errno.h>
-
-EXPORT_SYMBOL(posix_acl_init);
-EXPORT_SYMBOL(posix_acl_alloc);
-EXPORT_SYMBOL(posix_acl_valid);
-EXPORT_SYMBOL(posix_acl_equiv_mode);
-EXPORT_SYMBOL(posix_acl_from_mode);
-
-/*
- * Init a fresh posix_acl
- */
-void
-posix_acl_init(struct posix_acl *acl, int count)
-{
- atomic_set(&acl->a_refcount, 1);
- acl->a_count = count;
-}
-
-/*
- * Allocate a new ACL with the specified number of entries.
- */
-struct posix_acl *
-posix_acl_alloc(int count, gfp_t flags)
-{
- const size_t size = sizeof(struct posix_acl) +
- count * sizeof(struct posix_acl_entry);
- struct posix_acl *acl = kmalloc(size, flags);
- if (acl)
- posix_acl_init(acl, count);
- return acl;
-}
-
-/*
- * Clone an ACL.
- */
-static struct posix_acl *
-posix_acl_clone(const struct posix_acl *acl, gfp_t flags)
-{
- struct posix_acl *clone = NULL;
-
- if (acl) {
- int size = sizeof(struct posix_acl) + acl->a_count *
- sizeof(struct posix_acl_entry);
- clone = kmemdup(acl, size, flags);
- if (clone)
- atomic_set(&clone->a_refcount, 1);
- }
- return clone;
-}
-
-/*
- * Check if an acl is valid. Returns 0 if it is, or -E... otherwise.
- */
-int
-posix_acl_valid(const struct posix_acl *acl)
-{
- const struct posix_acl_entry *pa, *pe;
- int state = ACL_USER_OBJ;
- unsigned int id = 0; /* keep gcc happy */
- int needs_mask = 0;
-
- FOREACH_ACL_ENTRY(pa, acl, pe) {
- if (pa->e_perm & ~(ACL_READ|ACL_WRITE|ACL_EXECUTE))
- return -EINVAL;
- switch (pa->e_tag) {
- case ACL_USER_OBJ:
- if (state == ACL_USER_OBJ) {
- id = 0;
- state = ACL_USER;
- break;
- }
- return -EINVAL;
-
- case ACL_USER:
- if (state != ACL_USER)
- return -EINVAL;
- if (pa->e_id == ACL_UNDEFINED_ID ||
- pa->e_id < id)
- return -EINVAL;
- id = pa->e_id + 1;
- needs_mask = 1;
- break;
-
- case ACL_GROUP_OBJ:
- if (state == ACL_USER) {
- id = 0;
- state = ACL_GROUP;
- break;
- }
- return -EINVAL;
-
- case ACL_GROUP:
- if (state != ACL_GROUP)
- return -EINVAL;
- if (pa->e_id == ACL_UNDEFINED_ID ||
- pa->e_id < id)
- return -EINVAL;
- id = pa->e_id + 1;
- needs_mask = 1;
- break;
-
- case ACL_MASK:
- if (state != ACL_GROUP)
- return -EINVAL;
- state = ACL_OTHER;
- break;
-
- case ACL_OTHER:
- if (state == ACL_OTHER ||
- (state == ACL_GROUP && !needs_mask)) {
- state = 0;
- break;
- }
- return -EINVAL;
-
- default:
- return -EINVAL;
- }
- }
- if (state == 0)
- return 0;
- return -EINVAL;
-}
-
-/*
- * Returns 0 if the acl can be exactly represented in the traditional
- * file mode permission bits, or else 1. Returns -E... on error.
- */
-int
-posix_acl_equiv_mode(const struct posix_acl *acl, umode_t *mode_p)
-{
- const struct posix_acl_entry *pa, *pe;
- umode_t mode = 0;
- int not_equiv = 0;
-
- FOREACH_ACL_ENTRY(pa, acl, pe) {
- switch (pa->e_tag) {
- case ACL_USER_OBJ:
- mode |= (pa->e_perm & S_IRWXO) << 6;
- break;
- case ACL_GROUP_OBJ:
- mode |= (pa->e_perm & S_IRWXO) << 3;
- break;
- case ACL_OTHER:
- mode |= pa->e_perm & S_IRWXO;
- break;
- case ACL_MASK:
- mode = (mode & ~S_IRWXG) |
- ((pa->e_perm & S_IRWXO) << 3);
- not_equiv = 1;
- break;
- case ACL_USER:
- case ACL_GROUP:
- not_equiv = 1;
- break;
- default:
- return -EINVAL;
- }
- }
- if (mode_p)
- *mode_p = (*mode_p & ~S_IRWXUGO) | mode;
- return not_equiv;
-}
-
-/*
- * Create an ACL representing the file mode permission bits of an inode.
- */
-struct posix_acl *
-posix_acl_from_mode(umode_t mode, gfp_t flags)
-{
- struct posix_acl *acl = posix_acl_alloc(3, flags);
- if (!acl)
- return ERR_PTR(-ENOMEM);
-
- acl->a_entries[0].e_tag = ACL_USER_OBJ;
- acl->a_entries[0].e_id = ACL_UNDEFINED_ID;
- acl->a_entries[0].e_perm = (mode & S_IRWXU) >> 6;
-
- acl->a_entries[1].e_tag = ACL_GROUP_OBJ;
- acl->a_entries[1].e_id = ACL_UNDEFINED_ID;
- acl->a_entries[1].e_perm = (mode & S_IRWXG) >> 3;
-
- acl->a_entries[2].e_tag = ACL_OTHER;
- acl->a_entries[2].e_id = ACL_UNDEFINED_ID;
- acl->a_entries[2].e_perm = (mode & S_IRWXO);
- return acl;
-}
-
-/*
- * Return 0 if current is granted want access to the inode
- * by the acl. Returns -E... otherwise.
- */
-int
-posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
-{
- const struct posix_acl_entry *pa, *pe, *mask_obj;
- int found = 0;
-
- want &= MAY_READ | MAY_WRITE | MAY_EXEC | MAY_NOT_BLOCK;
-
- FOREACH_ACL_ENTRY(pa, acl, pe) {
- switch(pa->e_tag) {
- case ACL_USER_OBJ:
- /* (May have been checked already) */
- if (inode->i_uid == current_fsuid())
- goto check_perm;
- break;
- case ACL_USER:
- if (pa->e_id == current_fsuid())
- goto mask;
- break;
- case ACL_GROUP_OBJ:
- if (in_group_p(inode->i_gid)) {
- found = 1;
- if ((pa->e_perm & want) == want)
- goto mask;
- }
- break;
- case ACL_GROUP:
- if (in_group_p(pa->e_id)) {
- found = 1;
- if ((pa->e_perm & want) == want)
- goto mask;
- }
- break;
- case ACL_MASK:
- break;
- case ACL_OTHER:
- if (found)
- return -EACCES;
- else
- goto check_perm;
- default:
- return -EIO;
- }
- }
- return -EIO;
-
-mask:
- for (mask_obj = pa+1; mask_obj != pe; mask_obj++) {
- if (mask_obj->e_tag == ACL_MASK) {
- if ((pa->e_perm & mask_obj->e_perm & want) == want)
- return 0;
- return -EACCES;
- }
- }
-
-check_perm:
- if ((pa->e_perm & want) == want)
- return 0;
- return -EACCES;
-}
-
-/*
- * Modify acl when creating a new inode. The caller must ensure the acl is
- * only referenced once.
- *
- * mode_p initially must contain the mode parameter to the open() / creat()
- * system calls. All permissions that are not granted by the acl are removed.
- * The permissions in the acl are changed to reflect the mode_p parameter.
- */
-static int posix_acl_create_masq(struct posix_acl *acl, umode_t *mode_p)
-{
- struct posix_acl_entry *pa, *pe;
- struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL;
- umode_t mode = *mode_p;
- int not_equiv = 0;
-
- /* assert(atomic_read(acl->a_refcount) == 1); */
-
- FOREACH_ACL_ENTRY(pa, acl, pe) {
- switch(pa->e_tag) {
- case ACL_USER_OBJ:
- pa->e_perm &= (mode >> 6) | ~S_IRWXO;
- mode &= (pa->e_perm << 6) | ~S_IRWXU;
- break;
-
- case ACL_USER:
- case ACL_GROUP:
- not_equiv = 1;
- break;
-
- case ACL_GROUP_OBJ:
- group_obj = pa;
- break;
-
- case ACL_OTHER:
- pa->e_perm &= mode | ~S_IRWXO;
- mode &= pa->e_perm | ~S_IRWXO;
- break;
-
- case ACL_MASK:
- mask_obj = pa;
- not_equiv = 1;
- break;
-
- default:
- return -EIO;
- }
- }
-
- if (mask_obj) {
- mask_obj->e_perm &= (mode >> 3) | ~S_IRWXO;
- mode &= (mask_obj->e_perm << 3) | ~S_IRWXG;
- } else {
- if (!group_obj)
- return -EIO;
- group_obj->e_perm &= (mode >> 3) | ~S_IRWXO;
- mode &= (group_obj->e_perm << 3) | ~S_IRWXG;
- }
-
- *mode_p = (*mode_p & ~S_IRWXUGO) | mode;
- return not_equiv;
-}
-
-/*
- * Modify the ACL for the chmod syscall.
- */
-static int posix_acl_chmod_masq(struct posix_acl *acl, umode_t mode)
-{
- struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL;
- struct posix_acl_entry *pa, *pe;
-
- /* assert(atomic_read(acl->a_refcount) == 1); */
-
- FOREACH_ACL_ENTRY(pa, acl, pe) {
- switch(pa->e_tag) {
- case ACL_USER_OBJ:
- pa->e_perm = (mode & S_IRWXU) >> 6;
- break;
-
- case ACL_USER:
- case ACL_GROUP:
- break;
-
- case ACL_GROUP_OBJ:
- group_obj = pa;
- break;
-
- case ACL_MASK:
- mask_obj = pa;
- break;
-
- case ACL_OTHER:
- pa->e_perm = (mode & S_IRWXO);
- break;
-
- default:
- return -EIO;
- }
- }
-
- if (mask_obj) {
- mask_obj->e_perm = (mode & S_IRWXG) >> 3;
- } else {
- if (!group_obj)
- return -EIO;
- group_obj->e_perm = (mode & S_IRWXG) >> 3;
- }
-
- return 0;
-}
-
-int
-posix_acl_create(struct posix_acl **acl, gfp_t gfp, umode_t *mode_p)
-{
- struct posix_acl *clone = posix_acl_clone(*acl, gfp);
- int err = -ENOMEM;
- if (clone) {
- err = posix_acl_create_masq(clone, mode_p);
- if (err < 0) {
- posix_acl_release(clone);
- clone = NULL;
- }
- }
- posix_acl_release(*acl);
- *acl = clone;
- return err;
-}
-EXPORT_SYMBOL(posix_acl_create);
-
-int
-posix_acl_chmod(struct posix_acl **acl, gfp_t gfp, umode_t mode)
-{
- struct posix_acl *clone = posix_acl_clone(*acl, gfp);
- int err = -ENOMEM;
- if (clone) {
- err = posix_acl_chmod_masq(clone, mode);
- if (err) {
- posix_acl_release(clone);
- clone = NULL;
- }
- }
- posix_acl_release(*acl);
- *acl = clone;
- return err;
-}
-EXPORT_SYMBOL(posix_acl_chmod);
generated by cgit (git 2.34.1) at 2024-12-20 14:32:56 +0000