From: Borislav Petkov <petkov@uni-muenster.de>
[linux-2.6] / security / capability.c
1 /*
2  *  Capabilities Linux Security Module
3  *
4  *      This program is free software; you can redistribute it and/or modify
5  *      it under the terms of the GNU General Public License as published by
6  *      the Free Software Foundation; either version 2 of the License, or
7  *      (at your option) any later version.
8  *
9  */
10
11 #include <linux/config.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/security.h>
16 #include <linux/file.h>
17 #include <linux/mm.h>
18 #include <linux/mman.h>
19 #include <linux/pagemap.h>
20 #include <linux/swap.h>
21 #include <linux/smp_lock.h>
22 #include <linux/skbuff.h>
23 #include <linux/netlink.h>
24 #include <linux/ptrace.h>
25 #include <linux/moduleparam.h>
26
27 static struct security_operations capability_ops = {
28         .ptrace =                       cap_ptrace,
29         .capget =                       cap_capget,
30         .capset_check =                 cap_capset_check,
31         .capset_set =                   cap_capset_set,
32         .capable =                      cap_capable,
33         .settime =                      cap_settime,
34         .netlink_send =                 cap_netlink_send,
35         .netlink_recv =                 cap_netlink_recv,
36
37         .bprm_apply_creds =             cap_bprm_apply_creds,
38         .bprm_set_security =            cap_bprm_set_security,
39         .bprm_secureexec =              cap_bprm_secureexec,
40
41         .inode_setxattr =               cap_inode_setxattr,
42         .inode_removexattr =            cap_inode_removexattr,
43
44         .task_post_setuid =             cap_task_post_setuid,
45         .task_reparent_to_init =        cap_task_reparent_to_init,
46
47         .syslog =                       cap_syslog,
48
49         .vm_enough_memory =             cap_vm_enough_memory,
50 };
51
52 /* flag to keep track of how we were registered */
53 static int secondary;
54
55 static int capability_disable;
56 module_param_named(disable, capability_disable, int, 0);
57 MODULE_PARM_DESC(disable, "To disable capabilities module set disable = 1");
58
59 static int __init capability_init (void)
60 {
61         if (capability_disable) {
62                 printk(KERN_INFO "Capabilities disabled at initialization\n");
63                 return 0;
64         }
65         /* register ourselves with the security framework */
66         if (register_security (&capability_ops)) {
67                 /* try registering with primary module */
68                 if (mod_reg_security (KBUILD_MODNAME, &capability_ops)) {
69                         printk (KERN_INFO "Failure registering capabilities "
70                                 "with primary security module.\n");
71                         return -EINVAL;
72                 }
73                 secondary = 1;
74         }
75         printk (KERN_INFO "Capability LSM initialized%s\n",
76                 secondary ? " as secondary" : "");
77         return 0;
78 }
79
80 static void __exit capability_exit (void)
81 {
82         if (capability_disable)
83                 return;
84         /* remove ourselves from the security framework */
85         if (secondary) {
86                 if (mod_unreg_security (KBUILD_MODNAME, &capability_ops))
87                         printk (KERN_INFO "Failure unregistering capabilities "
88                                 "with primary module.\n");
89                 return;
90         }
91
92         if (unregister_security (&capability_ops)) {
93                 printk (KERN_INFO
94                         "Failure unregistering capabilities with the kernel\n");
95         }
96 }
97
98 security_initcall (capability_init);
99 module_exit (capability_exit);
100
101 MODULE_DESCRIPTION("Standard Linux Capabilities Security Module");
102 MODULE_LICENSE("GPL");