tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Simplified MAC Kernel (smack) security module
4 *
5 * This file contains the Smack netfilter implementation
6 *
7 * Author:
8 * Casey Schaufler <casey@schaufler-ca.com>
9 *
10 * Copyright (C) 2014 Casey Schaufler <casey@schaufler-ca.com>
11 * Copyright (C) 2014 Intel Corporation.
12 */
13
14#include <linux/netfilter_ipv4.h>
15#include <linux/netfilter_ipv6.h>
16#include <linux/netdevice.h>
17#include <net/inet_sock.h>
18#include <net/net_namespace.h>
19#include "smack.h"
20
21#if IS_ENABLED(CONFIG_IPV6)
22
23static unsigned int smack_ipv6_output(void *priv,
24 struct sk_buff *skb,
25 const struct nf_hook_state *state)
26{
27 struct sock *sk = skb_to_full_sk(skb);
28 struct socket_smack *ssp;
29 struct smack_known *skp;
30
31 if (sk && sk->sk_security) {
32 ssp = sk->sk_security;
33 skp = ssp->smk_out;
34 skb->secmark = skp->smk_secid;
35 }
36
37 return NF_ACCEPT;
38}
39#endif /* IPV6 */
40
41static unsigned int smack_ipv4_output(void *priv,
42 struct sk_buff *skb,
43 const struct nf_hook_state *state)
44{
45 struct sock *sk = skb_to_full_sk(skb);
46 struct socket_smack *ssp;
47 struct smack_known *skp;
48
49 if (sk && sk->sk_security) {
50 ssp = sk->sk_security;
51 skp = ssp->smk_out;
52 skb->secmark = skp->smk_secid;
53 }
54
55 return NF_ACCEPT;
56}
57
58static const struct nf_hook_ops smack_nf_ops[] = {
59 {
60 .hook = smack_ipv4_output,
61 .pf = NFPROTO_IPV4,
62 .hooknum = NF_INET_LOCAL_OUT,
63 .priority = NF_IP_PRI_SELINUX_FIRST,
64 },
65#if IS_ENABLED(CONFIG_IPV6)
66 {
67 .hook = smack_ipv6_output,
68 .pf = NFPROTO_IPV6,
69 .hooknum = NF_INET_LOCAL_OUT,
70 .priority = NF_IP6_PRI_SELINUX_FIRST,
71 },
72#endif /* IPV6 */
73};
74
75static int __net_init smack_nf_register(struct net *net)
76{
77 return nf_register_net_hooks(net, smack_nf_ops,
78 ARRAY_SIZE(smack_nf_ops));
79}
80
81static void __net_exit smack_nf_unregister(struct net *net)
82{
83 nf_unregister_net_hooks(net, smack_nf_ops, ARRAY_SIZE(smack_nf_ops));
84}
85
86static struct pernet_operations smack_net_ops = {
87 .init = smack_nf_register,
88 .exit = smack_nf_unregister,
89};
90
91static int __init smack_nf_ip_init(void)
92{
93 if (smack_enabled == 0)
94 return 0;
95
96 printk(KERN_DEBUG "Smack: Registering netfilter hooks\n");
97 return register_pernet_subsys(&smack_net_ops);
98}
99
100__initcall(smack_nf_ip_init);