| Casey Schaufler | 69f287a | 2014-12-12 17:08:40 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * Simplified MAC Kernel (smack) security module |
| 3 | * |
| 4 | * This file contains the Smack netfilter implementation |
| 5 | * |
| 6 | * Author: |
| 7 | * Casey Schaufler <casey@schaufler-ca.com> |
| 8 | * |
| 9 | * Copyright (C) 2014 Casey Schaufler <casey@schaufler-ca.com> |
| 10 | * Copyright (C) 2014 Intel Corporation. |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU General Public License version 2, |
| 14 | * as published by the Free Software Foundation. |
| 15 | */ |
| 16 | |
| 17 | #include <linux/netfilter_ipv4.h> |
| 18 | #include <linux/netfilter_ipv6.h> |
| 19 | #include <linux/netdevice.h> |
| 20 | #include "smack.h" |
| 21 | |
| 22 | #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| 23 | |
| 24 | static unsigned int smack_ipv6_output(const struct nf_hook_ops *ops, |
| 25 | struct sk_buff *skb, |
| 26 | const struct net_device *in, |
| 27 | const struct net_device *out, |
| 28 | int (*okfn)(struct sk_buff *)) |
| 29 | { |
| 30 | struct socket_smack *ssp; |
| 31 | struct smack_known *skp; |
| 32 | |
| 33 | if (skb && skb->sk && skb->sk->sk_security) { |
| 34 | ssp = skb->sk->sk_security; |
| 35 | skp = ssp->smk_out; |
| 36 | skb->secmark = skp->smk_secid; |
| 37 | } |
| 38 | |
| 39 | return NF_ACCEPT; |
| 40 | } |
| 41 | #endif /* IPV6 */ |
| 42 | |
| 43 | static unsigned int smack_ipv4_output(const struct nf_hook_ops *ops, |
| 44 | struct sk_buff *skb, |
| 45 | const struct net_device *in, |
| 46 | const struct net_device *out, |
| 47 | int (*okfn)(struct sk_buff *)) |
| 48 | { |
| 49 | struct socket_smack *ssp; |
| 50 | struct smack_known *skp; |
| 51 | |
| 52 | if (skb && skb->sk && skb->sk->sk_security) { |
| 53 | ssp = skb->sk->sk_security; |
| 54 | skp = ssp->smk_out; |
| 55 | skb->secmark = skp->smk_secid; |
| 56 | } |
| 57 | |
| 58 | return NF_ACCEPT; |
| 59 | } |
| 60 | |
| 61 | static struct nf_hook_ops smack_nf_ops[] = { |
| 62 | { |
| 63 | .hook = smack_ipv4_output, |
| 64 | .owner = THIS_MODULE, |
| 65 | .pf = NFPROTO_IPV4, |
| 66 | .hooknum = NF_INET_LOCAL_OUT, |
| 67 | .priority = NF_IP_PRI_SELINUX_FIRST, |
| 68 | }, |
| 69 | #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| 70 | { |
| 71 | .hook = smack_ipv6_output, |
| 72 | .owner = THIS_MODULE, |
| 73 | .pf = NFPROTO_IPV6, |
| 74 | .hooknum = NF_INET_LOCAL_OUT, |
| 75 | .priority = NF_IP6_PRI_SELINUX_FIRST, |
| 76 | }, |
| 77 | #endif /* IPV6 */ |
| 78 | }; |
| 79 | |
| 80 | static int __init smack_nf_ip_init(void) |
| 81 | { |
| 82 | int err; |
| 83 | |
| 84 | if (smack_enabled == 0) |
| 85 | return 0; |
| 86 | |
| 87 | printk(KERN_DEBUG "Smack: Registering netfilter hooks\n"); |
| 88 | |
| 89 | err = nf_register_hooks(smack_nf_ops, ARRAY_SIZE(smack_nf_ops)); |
| 90 | if (err) |
| 91 | pr_info("Smack: nf_register_hooks: error %d\n", err); |
| 92 | |
| 93 | return 0; |
| 94 | } |
| 95 | |
| 96 | __initcall(smack_nf_ip_init); |