diff options
Diffstat (limited to 'security/apparmor/resource.c')
-rw-r--r-- | security/apparmor/resource.c | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/security/apparmor/resource.c b/security/apparmor/resource.c new file mode 100644 index 00000000000..4a368f1fd36 --- /dev/null +++ b/security/apparmor/resource.c | |||
@@ -0,0 +1,134 @@ | |||
1 | /* | ||
2 | * AppArmor security module | ||
3 | * | ||
4 | * This file contains AppArmor resource mediation and attachment | ||
5 | * | ||
6 | * Copyright (C) 1998-2008 Novell/SUSE | ||
7 | * Copyright 2009-2010 Canonical Ltd. | ||
8 | * | ||
9 | * This program is free software; you can redistribute it and/or | ||
10 | * modify it under the terms of the GNU General Public License as | ||
11 | * published by the Free Software Foundation, version 2 of the | ||
12 | * License. | ||
13 | */ | ||
14 | |||
15 | #include <linux/audit.h> | ||
16 | |||
17 | #include "include/audit.h" | ||
18 | #include "include/resource.h" | ||
19 | #include "include/policy.h" | ||
20 | |||
21 | /* | ||
22 | * Table of rlimit names: we generate it from resource.h. | ||
23 | */ | ||
24 | #include "rlim_names.h" | ||
25 | |||
26 | /* audit callback for resource specific fields */ | ||
27 | static void audit_cb(struct audit_buffer *ab, void *va) | ||
28 | { | ||
29 | struct common_audit_data *sa = va; | ||
30 | |||
31 | audit_log_format(ab, " rlimit=%s value=%lu", | ||
32 | rlim_names[sa->aad.rlim.rlim], sa->aad.rlim.max); | ||
33 | } | ||
34 | |||
35 | /** | ||
36 | * audit_resource - audit setting resource limit | ||
37 | * @profile: profile being enforced (NOT NULL) | ||
38 | * @resoure: rlimit being auditing | ||
39 | * @value: value being set | ||
40 | * @error: error value | ||
41 | * | ||
42 | * Returns: 0 or sa->error else other error code on failure | ||
43 | */ | ||
44 | static int audit_resource(struct aa_profile *profile, unsigned int resource, | ||
45 | unsigned long value, int error) | ||
46 | { | ||
47 | struct common_audit_data sa; | ||
48 | |||
49 | COMMON_AUDIT_DATA_INIT(&sa, NONE); | ||
50 | sa.aad.op = OP_SETRLIMIT, | ||
51 | sa.aad.rlim.rlim = resource; | ||
52 | sa.aad.rlim.max = value; | ||
53 | sa.aad.error = error; | ||
54 | return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_KERNEL, &sa, | ||
55 | audit_cb); | ||
56 | } | ||
57 | |||
58 | /** | ||
59 | * aa_map_resouce - map compiled policy resource to internal # | ||
60 | * @resource: flattened policy resource number | ||
61 | * | ||
62 | * Returns: resource # for the current architecture. | ||
63 | * | ||
64 | * rlimit resource can vary based on architecture, map the compiled policy | ||
65 | * resource # to the internal representation for the architecture. | ||
66 | */ | ||
67 | int aa_map_resource(int resource) | ||
68 | { | ||
69 | return rlim_map[resource]; | ||
70 | } | ||
71 | |||
72 | /** | ||
73 | * aa_task_setrlimit - test permission to set an rlimit | ||
74 | * @profile - profile confining the task (NOT NULL) | ||
75 | * @resource - the resource being set | ||
76 | * @new_rlim - the new resource limit (NOT NULL) | ||
77 | * | ||
78 | * Control raising the processes hard limit. | ||
79 | * | ||
80 | * Returns: 0 or error code if setting resource failed | ||
81 | */ | ||
82 | int aa_task_setrlimit(struct aa_profile *profile, unsigned int resource, | ||
83 | struct rlimit *new_rlim) | ||
84 | { | ||
85 | int error = 0; | ||
86 | |||
87 | if (profile->rlimits.mask & (1 << resource) && | ||
88 | new_rlim->rlim_max > profile->rlimits.limits[resource].rlim_max) | ||
89 | |||
90 | error = audit_resource(profile, resource, new_rlim->rlim_max, | ||
91 | -EACCES); | ||
92 | |||
93 | return error; | ||
94 | } | ||
95 | |||
96 | /** | ||
97 | * __aa_transition_rlimits - apply new profile rlimits | ||
98 | * @old: old profile on task (NOT NULL) | ||
99 | * @new: new profile with rlimits to apply (NOT NULL) | ||
100 | */ | ||
101 | void __aa_transition_rlimits(struct aa_profile *old, struct aa_profile *new) | ||
102 | { | ||
103 | unsigned int mask = 0; | ||
104 | struct rlimit *rlim, *initrlim; | ||
105 | int i; | ||
106 | |||
107 | /* for any rlimits the profile controlled reset the soft limit | ||
108 | * to the less of the tasks hard limit and the init tasks soft limit | ||
109 | */ | ||
110 | if (old->rlimits.mask) { | ||
111 | for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) { | ||
112 | if (old->rlimits.mask & mask) { | ||
113 | rlim = current->signal->rlim + i; | ||
114 | initrlim = init_task.signal->rlim + i; | ||
115 | rlim->rlim_cur = min(rlim->rlim_max, | ||
116 | initrlim->rlim_cur); | ||
117 | } | ||
118 | } | ||
119 | } | ||
120 | |||
121 | /* set any new hard limits as dictated by the new profile */ | ||
122 | if (!new->rlimits.mask) | ||
123 | return; | ||
124 | for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) { | ||
125 | if (!(new->rlimits.mask & mask)) | ||
126 | continue; | ||
127 | |||
128 | rlim = current->signal->rlim + i; | ||
129 | rlim->rlim_max = min(rlim->rlim_max, | ||
130 | new->rlimits.limits[i].rlim_max); | ||
131 | /* soft limit should not exceed hard limit */ | ||
132 | rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max); | ||
133 | } | ||
134 | } | ||