1 /* 2 * (C) 2010 Pablo Neira Ayuso <pablo@netfilter.org> 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 version 2 as 6 * published by the Free Software Foundation (or any later at your option). 7 */ 8 9 #include <linux/netfilter.h> 10 #include <linux/slab.h> 11 #include <linux/kernel.h> 12 #include <linux/moduleparam.h> 13 14 #include <net/netfilter/nf_conntrack.h> 15 #include <net/netfilter/nf_conntrack_extend.h> 16 #include <net/netfilter/nf_conntrack_timestamp.h> 17 18 static bool nf_ct_tstamp __read_mostly; 19 20 module_param_named(tstamp, nf_ct_tstamp, bool, 0644); 21 MODULE_PARM_DESC(tstamp, "Enable connection tracking flow timestamping."); 22 23 #ifdef CONFIG_SYSCTL 24 static struct ctl_table tstamp_sysctl_table[] = { 25 { 26 .procname = "nf_conntrack_timestamp", 27 .data = &init_net.ct.sysctl_tstamp, 28 .maxlen = sizeof(unsigned int), 29 .mode = 0644, 30 .proc_handler = proc_dointvec, 31 }, 32 {} 33 }; 34 #endif /* CONFIG_SYSCTL */ 35 36 static struct nf_ct_ext_type tstamp_extend __read_mostly = { 37 .len = sizeof(struct nf_conn_tstamp), 38 .align = __alignof__(struct nf_conn_tstamp), 39 .id = NF_CT_EXT_TSTAMP, 40 }; 41 42 #ifdef CONFIG_SYSCTL 43 static int nf_conntrack_tstamp_init_sysctl(struct net *net) 44 { 45 struct ctl_table *table; 46 47 table = kmemdup(tstamp_sysctl_table, sizeof(tstamp_sysctl_table), 48 GFP_KERNEL); 49 if (!table) 50 goto out; 51 52 table[0].data = &net->ct.sysctl_tstamp; 53 54 /* Don't export sysctls to unprivileged users */ 55 if (net->user_ns != &init_user_ns) 56 table[0].procname = NULL; 57 58 net->ct.tstamp_sysctl_header = register_net_sysctl(net, "net/netfilter", 59 table); 60 if (!net->ct.tstamp_sysctl_header) { 61 printk(KERN_ERR "nf_ct_tstamp: can't register to sysctl.\n"); 62 goto out_register; 63 } 64 return 0; 65 66 out_register: 67 kfree(table); 68 out: 69 return -ENOMEM; 70 } 71 72 static void nf_conntrack_tstamp_fini_sysctl(struct net *net) 73 { 74 struct ctl_table *table; 75 76 table = net->ct.tstamp_sysctl_header->ctl_table_arg; 77 unregister_net_sysctl_table(net->ct.tstamp_sysctl_header); 78 kfree(table); 79 } 80 #else 81 static int nf_conntrack_tstamp_init_sysctl(struct net *net) 82 { 83 return 0; 84 } 85 86 static void nf_conntrack_tstamp_fini_sysctl(struct net *net) 87 { 88 } 89 #endif 90 91 int nf_conntrack_tstamp_pernet_init(struct net *net) 92 { 93 net->ct.sysctl_tstamp = nf_ct_tstamp; 94 return nf_conntrack_tstamp_init_sysctl(net); 95 } 96 97 void nf_conntrack_tstamp_pernet_fini(struct net *net) 98 { 99 nf_conntrack_tstamp_fini_sysctl(net); 100 } 101 102 int nf_conntrack_tstamp_init(void) 103 { 104 int ret; 105 ret = nf_ct_extend_register(&tstamp_extend); 106 if (ret < 0) 107 pr_err("nf_ct_tstamp: Unable to register extension\n"); 108 return ret; 109 } 110 111 void nf_conntrack_tstamp_fini(void) 112 { 113 nf_ct_extend_unregister(&tstamp_extend); 114 } 115