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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/context.h"
19#include "include/resource.h"
20#include "include/policy.h"
21
22/*
23 * Table of rlimit names: we generate it from resource.h.
24 */
25#include "rlim_names.h"
26
27struct aa_fs_entry aa_fs_entry_rlimit[] = {
28 AA_FS_FILE_STRING("mask", AA_FS_RLIMIT_MASK),
29 { }
30};
31
32/* audit callback for resource specific fields */
33static void audit_cb(struct audit_buffer *ab, void *va)
34{
35 struct common_audit_data *sa = va;
36
37 audit_log_format(ab, " rlimit=%s value=%lu",
38 rlim_names[sa->aad->rlim.rlim], sa->aad->rlim.max);
39}
40
41/**
42 * audit_resource - audit setting resource limit
43 * @profile: profile being enforced (NOT NULL)
44 * @resoure: rlimit being auditing
45 * @value: value being set
46 * @error: error value
47 *
48 * Returns: 0 or sa->error else other error code on failure
49 */
50static int audit_resource(struct aa_profile *profile, unsigned int resource,
51 unsigned long value, int error)
52{
53 struct common_audit_data sa;
54 struct apparmor_audit_data aad = {0,};
55
56 sa.type = LSM_AUDIT_DATA_NONE;
57 sa.aad = &aad;
58 aad.op = OP_SETRLIMIT,
59 aad.rlim.rlim = resource;
60 aad.rlim.max = value;
61 aad.error = error;
62 return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_KERNEL, &sa,
63 audit_cb);
64}
65
66/**
67 * aa_map_resouce - map compiled policy resource to internal #
68 * @resource: flattened policy resource number
69 *
70 * Returns: resource # for the current architecture.
71 *
72 * rlimit resource can vary based on architecture, map the compiled policy
73 * resource # to the internal representation for the architecture.
74 */
75int aa_map_resource(int resource)
76{
77 return rlim_map[resource];
78}
79
80/**
81 * aa_task_setrlimit - test permission to set an rlimit
82 * @profile - profile confining the task (NOT NULL)
83 * @task - task the resource is being set on
84 * @resource - the resource being set
85 * @new_rlim - the new resource limit (NOT NULL)
86 *
87 * Control raising the processes hard limit.
88 *
89 * Returns: 0 or error code if setting resource failed
90 */
91int aa_task_setrlimit(struct aa_profile *profile, struct task_struct *task,
92 unsigned int resource, struct rlimit *new_rlim)
93{
94 struct aa_profile *task_profile;
95 int error = 0;
96
97 rcu_read_lock();
98 task_profile = aa_get_profile(aa_cred_profile(__task_cred(task)));
99 rcu_read_unlock();
100
101 /* TODO: extend resource control to handle other (non current)
102 * profiles. AppArmor rules currently have the implicit assumption
103 * that the task is setting the resource of a task confined with
104 * the same profile.
105 */
106 if (profile != task_profile ||
107 (profile->rlimits.mask & (1 << resource) &&
108 new_rlim->rlim_max > profile->rlimits.limits[resource].rlim_max))
109 error = -EACCES;
110
111 aa_put_profile(task_profile);
112
113 return audit_resource(profile, resource, new_rlim->rlim_max, error);
114}
115
116/**
117 * __aa_transition_rlimits - apply new profile rlimits
118 * @old: old profile on task (NOT NULL)
119 * @new: new profile with rlimits to apply (NOT NULL)
120 */
121void __aa_transition_rlimits(struct aa_profile *old, struct aa_profile *new)
122{
123 unsigned int mask = 0;
124 struct rlimit *rlim, *initrlim;
125 int i;
126
127 /* for any rlimits the profile controlled reset the soft limit
128 * to the less of the tasks hard limit and the init tasks soft limit
129 */
130 if (old->rlimits.mask) {
131 for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
132 if (old->rlimits.mask & mask) {
133 rlim = current->signal->rlim + i;
134 initrlim = init_task.signal->rlim + i;
135 rlim->rlim_cur = min(rlim->rlim_max,
136 initrlim->rlim_cur);
137 }
138 }
139 }
140
141 /* set any new hard limits as dictated by the new profile */
142 if (!new->rlimits.mask)
143 return;
144 for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
145 if (!(new->rlimits.mask & mask))
146 continue;
147
148 rlim = current->signal->rlim + i;
149 rlim->rlim_max = min(rlim->rlim_max,
150 new->rlimits.limits[i].rlim_max);
151 /* soft limit should not exceed hard limit */
152 rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max);
153 }
154}
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/context.h"
19#include "include/resource.h"
20#include "include/policy.h"
21
22/*
23 * Table of rlimit names: we generate it from resource.h.
24 */
25#include "rlim_names.h"
26
27struct aa_fs_entry aa_fs_entry_rlimit[] = {
28 AA_FS_FILE_STRING("mask", AA_FS_RLIMIT_MASK),
29 { }
30};
31
32/* audit callback for resource specific fields */
33static void audit_cb(struct audit_buffer *ab, void *va)
34{
35 struct common_audit_data *sa = va;
36
37 audit_log_format(ab, " rlimit=%s value=%lu",
38 rlim_names[sa->aad->rlim.rlim], sa->aad->rlim.max);
39}
40
41/**
42 * audit_resource - audit setting resource limit
43 * @profile: profile being enforced (NOT NULL)
44 * @resoure: rlimit being auditing
45 * @value: value being set
46 * @error: error value
47 *
48 * Returns: 0 or sa->error else other error code on failure
49 */
50static int audit_resource(struct aa_profile *profile, unsigned int resource,
51 unsigned long value, int error)
52{
53 struct common_audit_data sa;
54 struct apparmor_audit_data aad = {0,};
55
56 sa.type = LSM_AUDIT_DATA_NONE;
57 sa.aad = &aad;
58 aad.op = OP_SETRLIMIT,
59 aad.rlim.rlim = resource;
60 aad.rlim.max = value;
61 aad.error = error;
62 return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_KERNEL, &sa,
63 audit_cb);
64}
65
66/**
67 * aa_map_resouce - map compiled policy resource to internal #
68 * @resource: flattened policy resource number
69 *
70 * Returns: resource # for the current architecture.
71 *
72 * rlimit resource can vary based on architecture, map the compiled policy
73 * resource # to the internal representation for the architecture.
74 */
75int aa_map_resource(int resource)
76{
77 return rlim_map[resource];
78}
79
80/**
81 * aa_task_setrlimit - test permission to set an rlimit
82 * @profile - profile confining the task (NOT NULL)
83 * @task - task the resource is being set on
84 * @resource - the resource being set
85 * @new_rlim - the new resource limit (NOT NULL)
86 *
87 * Control raising the processes hard limit.
88 *
89 * Returns: 0 or error code if setting resource failed
90 */
91int aa_task_setrlimit(struct aa_profile *profile, struct task_struct *task,
92 unsigned int resource, struct rlimit *new_rlim)
93{
94 struct aa_profile *task_profile;
95 int error = 0;
96
97 rcu_read_lock();
98 task_profile = aa_get_profile(aa_cred_profile(__task_cred(task)));
99 rcu_read_unlock();
100
101 /* TODO: extend resource control to handle other (non current)
102 * profiles. AppArmor rules currently have the implicit assumption
103 * that the task is setting the resource of a task confined with
104 * the same profile.
105 */
106 if (profile != task_profile ||
107 (profile->rlimits.mask & (1 << resource) &&
108 new_rlim->rlim_max > profile->rlimits.limits[resource].rlim_max))
109 error = -EACCES;
110
111 aa_put_profile(task_profile);
112
113 return audit_resource(profile, resource, new_rlim->rlim_max, error);
114}
115
116/**
117 * __aa_transition_rlimits - apply new profile rlimits
118 * @old: old profile on task (NOT NULL)
119 * @new: new profile with rlimits to apply (NOT NULL)
120 */
121void __aa_transition_rlimits(struct aa_profile *old, struct aa_profile *new)
122{
123 unsigned int mask = 0;
124 struct rlimit *rlim, *initrlim;
125 int i;
126
127 /* for any rlimits the profile controlled reset the soft limit
128 * to the less of the tasks hard limit and the init tasks soft limit
129 */
130 if (old->rlimits.mask) {
131 for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
132 if (old->rlimits.mask & mask) {
133 rlim = current->signal->rlim + i;
134 initrlim = init_task.signal->rlim + i;
135 rlim->rlim_cur = min(rlim->rlim_max,
136 initrlim->rlim_cur);
137 }
138 }
139 }
140
141 /* set any new hard limits as dictated by the new profile */
142 if (!new->rlimits.mask)
143 return;
144 for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
145 if (!(new->rlimits.mask & mask))
146 continue;
147
148 rlim = current->signal->rlim + i;
149 rlim->rlim_max = min(rlim->rlim_max,
150 new->rlimits.limits[i].rlim_max);
151 /* soft limit should not exceed hard limit */
152 rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max);
153 }
154}