netfilter: nf_log: prepare net namespace support for loggers

This patch adds netns support to nf_log and it prepares netns
support for existing loggers. It is composed of four major
changes.

1) nf_log_register has been split to two functions: nf_log_register
   and nf_log_set. The new nf_log_register is used to globally
   register the nf_logger and nf_log_set is used for enabling
   pernet support from nf_loggers.

   Per netns is not yet complete after this patch, it comes in
   separate follow up patches.

2) Add net as a parameter of nf_log_bind_pf. Per netns is not
   yet complete after this patch, it only allows to bind the
   nf_logger to the protocol family from init_net and it skips
   other cases.

3) Adapt all nf_log_packet callers to pass netns as parameter.
   After this patch, this function only works for init_net.

4) Make the sysctl net/netfilter/nf_log pernet.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

include/net/netfilter/nf_log.h

@@ -49,12 +49,18 @@ struct nf_logger {
 int nf_log_register(u_int8_t pf, struct nf_logger *logger);
 void nf_log_unregister(struct nf_logger *logger);
 
-int nf_log_bind_pf(u_int8_t pf, const struct nf_logger *logger);
-void nf_log_unbind_pf(u_int8_t pf);
+void nf_log_set(struct net *net, u_int8_t pf,
+		const struct nf_logger *logger);
+void nf_log_unset(struct net *net, const struct nf_logger *logger);
+
+int nf_log_bind_pf(struct net *net, u_int8_t pf,
+		   const struct nf_logger *logger);
+void nf_log_unbind_pf(struct net *net, u_int8_t pf);
 
 /* Calls the registered backend logging function */
-__printf(7, 8)
-void nf_log_packet(u_int8_t pf,
+__printf(8, 9)
+void nf_log_packet(struct net *net,
+		   u_int8_t pf,
 		   unsigned int hooknum,
 		   const struct sk_buff *skb,
 		   const struct net_device *in,

include/net/netns/netfilter.h

@@ -2,10 +2,17 @@
 #define __NETNS_NETFILTER_H
 
 #include <linux/proc_fs.h>
+#include <linux/netfilter.h>
+
+struct nf_logger;
 
 struct netns_nf {
 #if defined CONFIG_PROC_FS
 	struct proc_dir_entry *proc_netfilter;
+#endif
+	const struct nf_logger __rcu *nf_loggers[NFPROTO_NUMPROTO];
+#ifdef CONFIG_SYSCTL
+	struct ctl_table_header *nf_log_dir_header;
 #endif
 };
 #endif

net/bridge/netfilter/ebt_log.c

@@ -176,17 +176,18 @@ ebt_log_tg(struct sk_buff *skb, const struct xt_action_param *par)
 {
 	const struct ebt_log_info *info = par->targinfo;
 	struct nf_loginfo li;
+	struct net *net = dev_net(par->in ? par->in : par->out);
 
 	li.type = NF_LOG_TYPE_LOG;
 	li.u.log.level = info->loglevel;
 	li.u.log.logflags = info->bitmask;
 
 	if (info->bitmask & EBT_LOG_NFLOG)
-		nf_log_packet(NFPROTO_BRIDGE, par->hooknum, skb, par->in,
-		              par->out, &li, "%s", info->prefix);
+		nf_log_packet(net, NFPROTO_BRIDGE, par->hooknum, skb,
+			      par->in, par->out, &li, "%s", info->prefix);
 	else
 		ebt_log_packet(NFPROTO_BRIDGE, par->hooknum, skb, par->in,
-		               par->out, &li, info->prefix);
+			       par->out, &li, info->prefix);
 	return EBT_CONTINUE;
 }
 

net/bridge/netfilter/ebt_nflog.c

@@ -24,14 +24,15 @@ ebt_nflog_tg(struct sk_buff *skb, const struct xt_action_param *par)
 {
 	const struct ebt_nflog_info *info = par->targinfo;
 	struct nf_loginfo li;
+	struct net *net = dev_net(par->in ? par->in : par->out);
 
 	li.type = NF_LOG_TYPE_ULOG;
 	li.u.ulog.copy_len = info->len;
 	li.u.ulog.group = info->group;
 	li.u.ulog.qthreshold = info->threshold;
 
-	nf_log_packet(PF_BRIDGE, par->hooknum, skb, par->in, par->out,
-	              &li, "%s", info->prefix);
+	nf_log_packet(net, PF_BRIDGE, par->hooknum, skb, par->in,
+		      par->out, &li, "%s", info->prefix);
 	return EBT_CONTINUE;
 }
 

net/ipv4/netfilter/ip_tables.c

@@ -258,6 +258,7 @@ static void trace_packet(const struct sk_buff *skb,
 	const char *hookname, *chainname, *comment;
 	const struct ipt_entry *iter;
 	unsigned int rulenum = 0;
+	struct net *net = dev_net(in ? in : out);
 
 	table_base = private->entries[smp_processor_id()];
 	root = get_entry(table_base, private->hook_entry[hook]);
@@ -270,7 +271,7 @@ static void trace_packet(const struct sk_buff *skb,
 		    &chainname, &comment, &rulenum) != 0)
 			break;
 
-	nf_log_packet(AF_INET, hook, skb, in, out, &trace_loginfo,
+	nf_log_packet(net, AF_INET, hook, skb, in, out, &trace_loginfo,
 		      "TRACE: %s:%s:%s:%u ",
 		      tablename, chainname, comment, rulenum);
 }

net/ipv4/netfilter/nf_conntrack_proto_icmp.c

@@ -187,16 +187,16 @@ icmp_error(struct net *net, struct nf_conn *tmpl,
 	icmph = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_ih), &_ih);
 	if (icmph == NULL) {
 		if (LOG_INVALID(net, IPPROTO_ICMP))
-			nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
-				      "nf_ct_icmp: short packet ");
+			nf_log_packet(net, PF_INET, 0, skb, NULL, NULL,
+				      NULL, "nf_ct_icmp: short packet ");
 		return -NF_ACCEPT;
 	}
 
 	/* See ip_conntrack_proto_tcp.c */
 	if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
 	    nf_ip_checksum(skb, hooknum, dataoff, 0)) {
 		if (LOG_INVALID(net, IPPROTO_ICMP))
-			nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, PF_INET, 0, skb, NULL, NULL, NULL,
 				      "nf_ct_icmp: bad HW ICMP checksum ");
 		return -NF_ACCEPT;
 	}
@@ -209,7 +209,7 @@ icmp_error(struct net *net, struct nf_conn *tmpl,
 	 */
 	if (icmph->type > NR_ICMP_TYPES) {
 		if (LOG_INVALID(net, IPPROTO_ICMP))
-			nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, PF_INET, 0, skb, NULL, NULL, NULL,
 				      "nf_ct_icmp: invalid ICMP type ");
 		return -NF_ACCEPT;
 	}

net/ipv6/netfilter/ip6_tables.c

@@ -284,6 +284,7 @@ static void trace_packet(const struct sk_buff *skb,
 	const char *hookname, *chainname, *comment;
 	const struct ip6t_entry *iter;
 	unsigned int rulenum = 0;
+	struct net *net = dev_net(in ? in : out);
 
 	table_base = private->entries[smp_processor_id()];
 	root = get_entry(table_base, private->hook_entry[hook]);
@@ -296,7 +297,7 @@ static void trace_packet(const struct sk_buff *skb,
 		    &chainname, &comment, &rulenum) != 0)
 			break;
 
-	nf_log_packet(AF_INET6, hook, skb, in, out, &trace_loginfo,
+	nf_log_packet(net, AF_INET6, hook, skb, in, out, &trace_loginfo,
 		      "TRACE: %s:%s:%s:%u ",
 		      tablename, chainname, comment, rulenum);
 }

net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c

@@ -131,7 +131,8 @@ static bool icmpv6_new(struct nf_conn *ct, const struct sk_buff *skb,
 			 type + 128);
 		nf_ct_dump_tuple_ipv6(&ct->tuplehash[0].tuple);
 		if (LOG_INVALID(nf_ct_net(ct), IPPROTO_ICMPV6))
-			nf_log_packet(PF_INET6, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(nf_ct_net(ct), PF_INET6, 0, skb, NULL,
+				      NULL, NULL,
 				      "nf_ct_icmpv6: invalid new with type %d ",
 				      type + 128);
 		return false;
@@ -203,15 +204,15 @@ icmpv6_error(struct net *net, struct nf_conn *tmpl,
 	icmp6h = skb_header_pointer(skb, dataoff, sizeof(_ih), &_ih);
 	if (icmp6h == NULL) {
 		if (LOG_INVALID(net, IPPROTO_ICMPV6))
-		nf_log_packet(PF_INET6, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, PF_INET6, 0, skb, NULL, NULL, NULL,
 			      "nf_ct_icmpv6: short packet ");
 		return -NF_ACCEPT;
 	}
 
 	if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
 	    nf_ip6_checksum(skb, hooknum, dataoff, IPPROTO_ICMPV6)) {
 		if (LOG_INVALID(net, IPPROTO_ICMPV6))
-			nf_log_packet(PF_INET6, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, PF_INET6, 0, skb, NULL, NULL, NULL,
 				      "nf_ct_icmpv6: ICMPv6 checksum failed ");
 		return -NF_ACCEPT;
 	}

net/netfilter/nf_conntrack_helper.c

@@ -353,7 +353,7 @@ void nf_ct_helper_log(struct sk_buff *skb, const struct nf_conn *ct,
 	/* rcu_read_lock()ed by nf_hook_slow */
 	helper = rcu_dereference(help->helper);
 
-	nf_log_packet(nf_ct_l3num(ct), 0, skb, NULL, NULL, NULL,
+	nf_log_packet(nf_ct_net(ct), nf_ct_l3num(ct), 0, skb, NULL, NULL, NULL,
 		      "nf_ct_%s: dropping packet: %pV ", helper->name, &vaf);
 
 	va_end(args);

net/netfilter/nf_conntrack_proto_dccp.c

@@ -456,7 +456,8 @@ static bool dccp_new(struct nf_conn *ct, const struct sk_buff *skb,
 
 out_invalid:
 	if (LOG_INVALID(net, IPPROTO_DCCP))
-		nf_log_packet(nf_ct_l3num(ct), 0, skb, NULL, NULL, NULL, msg);
+		nf_log_packet(net, nf_ct_l3num(ct), 0, skb, NULL, NULL,
+			      NULL, msg);
 	return false;
 }
 
@@ -542,13 +543,13 @@ static int dccp_packet(struct nf_conn *ct, const struct sk_buff *skb,
 
 		spin_unlock_bh(&ct->lock);
 		if (LOG_INVALID(net, IPPROTO_DCCP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				      "nf_ct_dccp: invalid packet ignored ");
 		return NF_ACCEPT;
 	case CT_DCCP_INVALID:
 		spin_unlock_bh(&ct->lock);
 		if (LOG_INVALID(net, IPPROTO_DCCP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				      "nf_ct_dccp: invalid state transition ");
 		return -NF_ACCEPT;
 	}
@@ -613,7 +614,7 @@ static int dccp_error(struct net *net, struct nf_conn *tmpl,
 
 out_invalid:
 	if (LOG_INVALID(net, IPPROTO_DCCP))
-		nf_log_packet(pf, 0, skb, NULL, NULL, NULL, msg);
+		nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, msg);
 	return -NF_ACCEPT;
 }
 

net/netfilter/nf_conntrack_proto_tcp.c

@@ -720,7 +720,7 @@ static bool tcp_in_window(const struct nf_conn *ct,
 		    tn->tcp_be_liberal)
 			res = true;
 		if (!res && LOG_INVALID(net, IPPROTO_TCP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 			"nf_ct_tcp: %s ",
 			before(seq, sender->td_maxend + 1) ?
 			after(end, sender->td_end - receiver->td_maxwin - 1) ?
@@ -772,15 +772,15 @@ static int tcp_error(struct net *net, struct nf_conn *tmpl,
 	th = skb_header_pointer(skb, dataoff, sizeof(_tcph), &_tcph);
 	if (th == NULL) {
 		if (LOG_INVALID(net, IPPROTO_TCP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				"nf_ct_tcp: short packet ");
 		return -NF_ACCEPT;
 	}
 
 	/* Not whole TCP header or malformed packet */
 	if (th->doff*4 < sizeof(struct tcphdr) || tcplen < th->doff*4) {
 		if (LOG_INVALID(net, IPPROTO_TCP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				"nf_ct_tcp: truncated/malformed packet ");
 		return -NF_ACCEPT;
 	}
@@ -793,7 +793,7 @@ static int tcp_error(struct net *net, struct nf_conn *tmpl,
 	if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
 	    nf_checksum(skb, hooknum, dataoff, IPPROTO_TCP, pf)) {
 		if (LOG_INVALID(net, IPPROTO_TCP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				  "nf_ct_tcp: bad TCP checksum ");
 		return -NF_ACCEPT;
 	}
@@ -802,7 +802,7 @@ static int tcp_error(struct net *net, struct nf_conn *tmpl,
 	tcpflags = (tcp_flag_byte(th) & ~(TCPHDR_ECE|TCPHDR_CWR|TCPHDR_PSH));
 	if (!tcp_valid_flags[tcpflags]) {
 		if (LOG_INVALID(net, IPPROTO_TCP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				  "nf_ct_tcp: invalid TCP flag combination ");
 		return -NF_ACCEPT;
 	}
@@ -949,7 +949,7 @@ static int tcp_packet(struct nf_conn *ct,
 		}
 		spin_unlock_bh(&ct->lock);
 		if (LOG_INVALID(net, IPPROTO_TCP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				  "nf_ct_tcp: invalid packet ignored in "
 				  "state %s ", tcp_conntrack_names[old_state]);
 		return NF_ACCEPT;
@@ -959,7 +959,7 @@ static int tcp_packet(struct nf_conn *ct,
 			 dir, get_conntrack_index(th), old_state);
 		spin_unlock_bh(&ct->lock);
 		if (LOG_INVALID(net, IPPROTO_TCP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				  "nf_ct_tcp: invalid state ");
 		return -NF_ACCEPT;
 	case TCP_CONNTRACK_CLOSE:
@@ -969,8 +969,8 @@ static int tcp_packet(struct nf_conn *ct,
 			/* Invalid RST  */
 			spin_unlock_bh(&ct->lock);
 			if (LOG_INVALID(net, IPPROTO_TCP))
-				nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
-					  "nf_ct_tcp: invalid RST ");
+				nf_log_packet(net, pf, 0, skb, NULL, NULL,
+					      NULL, "nf_ct_tcp: invalid RST ");
 			return -NF_ACCEPT;
 		}
 		if (index == TCP_RST_SET

net/netfilter/nf_conntrack_proto_udp.c

@@ -119,15 +119,15 @@ static int udp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb,
 	hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
 	if (hdr == NULL) {
 		if (LOG_INVALID(net, IPPROTO_UDP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				      "nf_ct_udp: short packet ");
 		return -NF_ACCEPT;
 	}
 
 	/* Truncated/malformed packets */
 	if (ntohs(hdr->len) > udplen || ntohs(hdr->len) < sizeof(*hdr)) {
 		if (LOG_INVALID(net, IPPROTO_UDP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				"nf_ct_udp: truncated/malformed packet ");
 		return -NF_ACCEPT;
 	}
@@ -143,7 +143,7 @@ static int udp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb,
 	if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
 	    nf_checksum(skb, hooknum, dataoff, IPPROTO_UDP, pf)) {
 		if (LOG_INVALID(net, IPPROTO_UDP))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				"nf_ct_udp: bad UDP checksum ");
 		return -NF_ACCEPT;
 	}

net/netfilter/nf_conntrack_proto_udplite.c

@@ -131,7 +131,7 @@ static int udplite_error(struct net *net, struct nf_conn *tmpl,
 	hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
 	if (hdr == NULL) {
 		if (LOG_INVALID(net, IPPROTO_UDPLITE))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				      "nf_ct_udplite: short packet ");
 		return -NF_ACCEPT;
 	}
@@ -141,15 +141,15 @@ static int udplite_error(struct net *net, struct nf_conn *tmpl,
 		cscov = udplen;
 	else if (cscov < sizeof(*hdr) || cscov > udplen) {
 		if (LOG_INVALID(net, IPPROTO_UDPLITE))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				"nf_ct_udplite: invalid checksum coverage ");
 		return -NF_ACCEPT;
 	}
 
 	/* UDPLITE mandates checksums */
 	if (!hdr->check) {
 		if (LOG_INVALID(net, IPPROTO_UDPLITE))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				      "nf_ct_udplite: checksum missing ");
 		return -NF_ACCEPT;
 	}
@@ -159,7 +159,7 @@ static int udplite_error(struct net *net, struct nf_conn *tmpl,
 	    nf_checksum_partial(skb, hooknum, dataoff, cscov, IPPROTO_UDP,
 	    			pf)) {
 		if (LOG_INVALID(net, IPPROTO_UDPLITE))
-			nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
 				      "nf_ct_udplite: bad UDPLite checksum ");
 		return -NF_ACCEPT;
 	}