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17#include <linux/netfilter_ipv4.h>
18#include <linux/netfilter_ipv6.h>
19#include <linux/netdevice.h>
20#include <net/inet_sock.h>
21#include <net/net_namespace.h>
22#include "smack.h"
23
24#if IS_ENABLED(CONFIG_IPV6)
25
26static unsigned int smack_ipv6_output(void *priv,
27 struct sk_buff *skb,
28 const struct nf_hook_state *state)
29{
30 struct sock *sk = skb_to_full_sk(skb);
31 struct socket_smack *ssp;
32 struct smack_known *skp;
33
34 if (sk && sk->sk_security) {
35 ssp = sk->sk_security;
36 skp = ssp->smk_out;
37 skb->secmark = skp->smk_secid;
38 }
39
40 return NF_ACCEPT;
41}
42#endif
43
44static unsigned int smack_ipv4_output(void *priv,
45 struct sk_buff *skb,
46 const struct nf_hook_state *state)
47{
48 struct sock *sk = skb_to_full_sk(skb);
49 struct socket_smack *ssp;
50 struct smack_known *skp;
51
52 if (sk && sk->sk_security) {
53 ssp = sk->sk_security;
54 skp = ssp->smk_out;
55 skb->secmark = skp->smk_secid;
56 }
57
58 return NF_ACCEPT;
59}
60
61static const struct nf_hook_ops smack_nf_ops[] = {
62 {
63 .hook = smack_ipv4_output,
64 .pf = NFPROTO_IPV4,
65 .hooknum = NF_INET_LOCAL_OUT,
66 .priority = NF_IP_PRI_SELINUX_FIRST,
67 },
68#if IS_ENABLED(CONFIG_IPV6)
69 {
70 .hook = smack_ipv6_output,
71 .pf = NFPROTO_IPV6,
72 .hooknum = NF_INET_LOCAL_OUT,
73 .priority = NF_IP6_PRI_SELINUX_FIRST,
74 },
75#endif
76};
77
78static int __net_init smack_nf_register(struct net *net)
79{
80 return nf_register_net_hooks(net, smack_nf_ops,
81 ARRAY_SIZE(smack_nf_ops));
82}
83
84static void __net_exit smack_nf_unregister(struct net *net)
85{
86 nf_unregister_net_hooks(net, smack_nf_ops, ARRAY_SIZE(smack_nf_ops));
87}
88
89static struct pernet_operations smack_net_ops = {
90 .init = smack_nf_register,
91 .exit = smack_nf_unregister,
92};
93
94static int __init smack_nf_ip_init(void)
95{
96 if (smack_enabled == 0)
97 return 0;
98
99 printk(KERN_DEBUG "Smack: Registering netfilter hooks\n");
100 return register_pernet_subsys(&smack_net_ops);
101}
102
103__initcall(smack_nf_ip_init);
104