LXR RHEL4/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
  27static 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        .netlink_send =                 cap_netlink_send,
  34        .netlink_recv =                 cap_netlink_recv,
  35
  36        .bprm_apply_creds =             cap_bprm_apply_creds,
  37        .bprm_set_security =            cap_bprm_set_security,
  38        .bprm_secureexec =              cap_bprm_secureexec,
  39
  40        .inode_setxattr =               cap_inode_setxattr,
  41        .inode_removexattr =            cap_inode_removexattr,
  42
  43        .task_post_setuid =             cap_task_post_setuid,
  44        .task_reparent_to_init =        cap_task_reparent_to_init,
  45
  46        .syslog =                       cap_syslog,
  47
  48        .vm_enough_memory =             cap_vm_enough_memory,
  49};
  50
  51#define MY_NAME __stringify(KBUILD_MODNAME)
  52
  53/* flag to keep track of how we were registered */
  54static int secondary;
  55
  56static int capability_disable;
  57module_param_named(disable, capability_disable, int, 0);
  58MODULE_PARM_DESC(disable, "To disable capabilities module set disable = 1");
  59
  60static int __init capability_init (void)
  61{
  62        if (capability_disable) {
  63                printk(KERN_INFO "Capabilities disabled at initialization\n");
  64                return 0;
  65        }
  66        /* register ourselves with the security framework */
  67        if (register_security (&capability_ops)) {
  68                /* try registering with primary module */
  69                if (mod_reg_security (MY_NAME, &capability_ops)) {
  70                        printk (KERN_INFO "Failure registering capabilities "
  71                                "with primary security module.\n");
  72                        return -EINVAL;
  73                }
  74                secondary = 1;
  75        }
  76        printk (KERN_INFO "Capability LSM initialized%s\n",
  77                secondary ? " as secondary" : "");
  78        return 0;
  79}
  80
  81static void __exit capability_exit (void)
  82{
  83        if (capability_disable)
  84                return;
  85        /* remove ourselves from the security framework */
  86        if (secondary) {
  87                if (mod_unreg_security (MY_NAME, &capability_ops))
  88                        printk (KERN_INFO "Failure unregistering capabilities "
  89                                "with primary module.\n");
  90                return;
  91        }
  92
  93        if (unregister_security (&capability_ops)) {
  94                printk (KERN_INFO
  95                        "Failure unregistering capabilities with the kernel\n");
  96        }
  97}
  98
  99security_initcall (capability_init);
 100module_exit (capability_exit);
 101
 102MODULE_DESCRIPTION("Standard Linux Capabilities Security Module");
 103MODULE_LICENSE("GPL");
 104