Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/fs/xattr_acl.c
Parent Directory | Revision Log
Revision 630 -
(show annotations)
(download)
Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
File MIME type: text/plain
File size: 2379 byte(s)
Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
File MIME type: text/plain
File size: 2379 byte(s)
Tag kernel26-2.6.12-alx-r9
1 | /* |
2 | * linux/fs/xattr_acl.c |
3 | * |
4 | * Almost all from linux/fs/ext2/acl.c: |
5 | * Copyright (C) 2001 by Andreas Gruenbacher, <a.gruenbacher@computer.org> |
6 | */ |
7 | |
8 | #include <linux/module.h> |
9 | #include <linux/sched.h> |
10 | #include <linux/slab.h> |
11 | #include <linux/fs.h> |
12 | #include <linux/posix_acl_xattr.h> |
13 | |
14 | |
15 | /* |
16 | * Convert from extended attribute to in-memory representation. |
17 | */ |
18 | struct posix_acl * |
19 | posix_acl_from_xattr(const void *value, size_t size) |
20 | { |
21 | posix_acl_xattr_header *header = (posix_acl_xattr_header *)value; |
22 | posix_acl_xattr_entry *entry = (posix_acl_xattr_entry *)(header+1), *end; |
23 | int count; |
24 | struct posix_acl *acl; |
25 | struct posix_acl_entry *acl_e; |
26 | |
27 | if (!value) |
28 | return NULL; |
29 | if (size < sizeof(posix_acl_xattr_header)) |
30 | return ERR_PTR(-EINVAL); |
31 | if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION)) |
32 | return ERR_PTR(-EOPNOTSUPP); |
33 | |
34 | count = posix_acl_xattr_count(size); |
35 | if (count < 0) |
36 | return ERR_PTR(-EINVAL); |
37 | if (count == 0) |
38 | return NULL; |
39 | |
40 | acl = posix_acl_alloc(count, GFP_KERNEL); |
41 | if (!acl) |
42 | return ERR_PTR(-ENOMEM); |
43 | acl_e = acl->a_entries; |
44 | |
45 | for (end = entry + count; entry != end; acl_e++, entry++) { |
46 | acl_e->e_tag = le16_to_cpu(entry->e_tag); |
47 | acl_e->e_perm = le16_to_cpu(entry->e_perm); |
48 | |
49 | switch(acl_e->e_tag) { |
50 | case ACL_USER_OBJ: |
51 | case ACL_GROUP_OBJ: |
52 | case ACL_MASK: |
53 | case ACL_OTHER: |
54 | acl_e->e_id = ACL_UNDEFINED_ID; |
55 | break; |
56 | |
57 | case ACL_USER: |
58 | case ACL_GROUP: |
59 | acl_e->e_id = le32_to_cpu(entry->e_id); |
60 | break; |
61 | |
62 | default: |
63 | goto fail; |
64 | } |
65 | } |
66 | return acl; |
67 | |
68 | fail: |
69 | posix_acl_release(acl); |
70 | return ERR_PTR(-EINVAL); |
71 | } |
72 | EXPORT_SYMBOL (posix_acl_from_xattr); |
73 | |
74 | /* |
75 | * Convert from in-memory to extended attribute representation. |
76 | */ |
77 | int |
78 | posix_acl_to_xattr(const struct posix_acl *acl, void *buffer, size_t size) |
79 | { |
80 | posix_acl_xattr_header *ext_acl = (posix_acl_xattr_header *)buffer; |
81 | posix_acl_xattr_entry *ext_entry = ext_acl->a_entries; |
82 | int real_size, n; |
83 | |
84 | real_size = posix_acl_xattr_size(acl->a_count); |
85 | if (!buffer) |
86 | return real_size; |
87 | if (real_size > size) |
88 | return -ERANGE; |
89 | |
90 | ext_acl->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION); |
91 | |
92 | for (n=0; n < acl->a_count; n++, ext_entry++) { |
93 | ext_entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag); |
94 | ext_entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm); |
95 | ext_entry->e_id = cpu_to_le32(acl->a_entries[n].e_id); |
96 | } |
97 | return real_size; |
98 | } |
99 | EXPORT_SYMBOL (posix_acl_to_xattr); |