netfilter: ebt_ulog: add net namespace support for ebt_ulog

Add pernet support to ebt_ulog by means of the new nf_log_set
function added in (30e0c6a netfilter: nf_log: prepare net
namespace support for loggers).

This patch also make ulog_buffers and netlink socket
ebtulognl per netns.

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

1 files changed, 88 insertions, 37 deletions

diff --git a/net/bridge/netfilter/ebt_ulog.c b/net/bridge/netfilter/ebt_ulog.c
index 442b0321acb9..0ddd612787e3 100644
--- a/net/bridge/netfilter/ebt_ulog.c
+++ b/net/bridge/netfilter/ebt_ulog.c
@@ -41,6 +41,7 @@
 #include <linux/netfilter_bridge/ebtables.h>
 #include <linux/netfilter_bridge/ebt_ulog.h>
 #include <net/netfilter/nf_log.h>
+#include <net/netns/generic.h>
 #include <net/sock.h>
 #include "../br_private.h"
 
@@ -62,13 +63,22 @@ typedef struct {
         spinlock_t lock;                /* the per-queue lock */
 } ebt_ulog_buff_t;
 
-static ebt_ulog_buff_t ulog_buffers[EBT_ULOG_MAXNLGROUPS];
-static struct sock *ebtulognl;
+static int ebt_ulog_net_id __read_mostly;
+struct ebt_ulog_net {
+        unsigned int nlgroup[EBT_ULOG_MAXNLGROUPS];
+        ebt_ulog_buff_t ulog_buffers[EBT_ULOG_MAXNLGROUPS];
+        struct sock *ebtulognl;
+};
+
+static struct ebt_ulog_net *ebt_ulog_pernet(struct net *net)
+{
+        return net_generic(net, ebt_ulog_net_id);
+}
 
 /* send one ulog_buff_t to userspace */
-static void ulog_send(unsigned int nlgroup)
+static void ulog_send(struct ebt_ulog_net *ebt, unsigned int nlgroup)
 {
-        ebt_ulog_buff_t *ub = &ulog_buffers[nlgroup];
+        ebt_ulog_buff_t *ub = &ebt->ulog_buffers[nlgroup];
 
         del_timer(&ub->timer);
 
@@ -80,7 +90,7 @@ static void ulog_send(unsigned int nlgroup)
                 ub->lastnlh->nlmsg_type = NLMSG_DONE;
 
         NETLINK_CB(ub->skb).dst_group = nlgroup + 1;
-        netlink_broadcast(ebtulognl, ub->skb, 0, nlgroup + 1, GFP_ATOMIC);
+        netlink_broadcast(ebt->ebtulognl, ub->skb, 0, nlgroup + 1, GFP_ATOMIC);
 
         ub->qlen = 0;
         ub->skb = NULL;
@@ -89,10 +99,15 @@ static void ulog_send(unsigned int nlgroup)
 /* timer function to flush queue in flushtimeout time */
 static void ulog_timer(unsigned long data)
 {
-        spin_lock_bh(&ulog_buffers[data].lock);
-        if (ulog_buffers[data].skb)
-                ulog_send(data);
-        spin_unlock_bh(&ulog_buffers[data].lock);
+        struct ebt_ulog_net *ebt = container_of((void *)data,
+                                                struct ebt_ulog_net,
+                                                nlgroup[*(unsigned int *)data]);
+
+        ebt_ulog_buff_t *ub = &ebt->ulog_buffers[*(unsigned int *)data];
+        spin_lock_bh(&ub->lock);
+        if (ub->skb)
+                ulog_send(ebt, *(unsigned int *)data);
+        spin_unlock_bh(&ub->lock);
 }
 
 static struct sk_buff *ulog_alloc_skb(unsigned int size)
@@ -123,8 +138,10 @@ static void ebt_ulog_packet(unsigned int hooknr, const struct sk_buff *skb,
         ebt_ulog_packet_msg_t *pm;
         size_t size, copy_len;
         struct nlmsghdr *nlh;
+        struct net *net = dev_net(in ? in : out);
+        struct ebt_ulog_net *ebt = ebt_ulog_pernet(net);
         unsigned int group = uloginfo->nlgroup;
-        ebt_ulog_buff_t *ub = &ulog_buffers[group];
+        ebt_ulog_buff_t *ub = &ebt->ulog_buffers[group];
         spinlock_t *lock = &ub->lock;
         ktime_t kt;
 
@@ -146,7 +163,7 @@ static void ebt_ulog_packet(unsigned int hooknr, const struct sk_buff *skb,
                 if (!(ub->skb = ulog_alloc_skb(size)))
                         goto unlock;
         } else if (size > skb_tailroom(ub->skb)) {
-                ulog_send(group);
+                ulog_send(ebt, group);
 
                 if (!(ub->skb = ulog_alloc_skb(size)))
                         goto unlock;
@@ -205,7 +222,7 @@ static void ebt_ulog_packet(unsigned int hooknr, const struct sk_buff *skb,
         ub->lastnlh = nlh;
 
         if (ub->qlen >= uloginfo->qthreshold)
-                ulog_send(group);
+                ulog_send(ebt, group);
         else if (!timer_pending(&ub->timer)) {
                 ub->timer.expires = jiffies + flushtimeout * HZ / 100;
                 add_timer(&ub->timer);
@@ -277,47 +294,39 @@ static struct nf_logger ebt_ulog_logger __read_mostly = {
         .me             = THIS_MODULE,
 };
 
-static int __init ebt_ulog_init(void)
+static int __net_init ebt_ulog_net_init(struct net *net)
 {
-        int ret;
         int i;
+        struct ebt_ulog_net *ebt = ebt_ulog_pernet(net);
+
         struct netlink_kernel_cfg cfg = {
                 .groups = EBT_ULOG_MAXNLGROUPS,
         };
 
-        if (nlbufsiz >= 128*1024) {
-                pr_warning("Netlink buffer has to be <= 128kB,"
-                           " please try a smaller nlbufsiz parameter.\n");
-                return -EINVAL;
-        }
-
         /* initialize ulog_buffers */
         for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) {
-                setup_timer(&ulog_buffers[i].timer, ulog_timer, i);
-                spin_lock_init(&ulog_buffers[i].lock);
+                ebt->nlgroup[i] = i;
+                setup_timer(&ebt->ulog_buffers[i].timer, ulog_timer,
+                            (unsigned long)&ebt->nlgroup[i]);
+                spin_lock_init(&ebt->ulog_buffers[i].lock);
         }
 
-        ebtulognl = netlink_kernel_create(&init_net, NETLINK_NFLOG, &cfg);
-        if (!ebtulognl)
-                ret = -ENOMEM;
-        else if ((ret = xt_register_target(&ebt_ulog_tg_reg)) != 0)
-                netlink_kernel_release(ebtulognl);
+        ebt->ebtulognl = netlink_kernel_create(net, NETLINK_NFLOG, &cfg);
+        if (!ebt->ebtulognl)
+                return -ENOMEM;
 
-        if (ret == 0)
-                nf_log_register(NFPROTO_BRIDGE, &ebt_ulog_logger);
-
-        return ret;
+        nf_log_set(net, NFPROTO_BRIDGE, &ebt_ulog_logger);
+        return 0;
 }
 
-static void __exit ebt_ulog_fini(void)
+static void __net_exit ebt_ulog_net_fini(struct net *net)
 {
-        ebt_ulog_buff_t *ub;
         int i;
+        struct ebt_ulog_net *ebt = ebt_ulog_pernet(net);
 
-        nf_log_unregister(&ebt_ulog_logger);
-        xt_unregister_target(&ebt_ulog_tg_reg);
+        nf_log_unset(net, &ebt_ulog_logger);
         for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) {
-                ub = &ulog_buffers[i];
+                ebt_ulog_buff_t *ub = &ebt->ulog_buffers[i];
                 del_timer(&ub->timer);
 
                 if (ub->skb) {
@@ -325,7 +334,49 @@ static void __exit ebt_ulog_fini(void)
                         ub->skb = NULL;
                 }
         }
-        netlink_kernel_release(ebtulognl);
+        netlink_kernel_release(ebt->ebtulognl);
+}
+
+static struct pernet_operations ebt_ulog_net_ops = {
+        .init = ebt_ulog_net_init,
+        .exit = ebt_ulog_net_fini,
+        .id   = &ebt_ulog_net_id,
+        .size = sizeof(struct ebt_ulog_net),
+};
+
+static int __init ebt_ulog_init(void)
+{
+        int ret;
+
+        if (nlbufsiz >= 128*1024) {
+                pr_warn("Netlink buffer has to be <= 128kB,"
+                        "please try a smaller nlbufsiz parameter.\n");
+                return -EINVAL;
+        }
+
+        ret = register_pernet_subsys(&ebt_ulog_net_ops);
+        if (ret)
+                goto out_pernet;
+
+        ret = xt_register_target(&ebt_ulog_tg_reg);
+        if (ret)
+                goto out_target;
+
+        nf_log_register(NFPROTO_BRIDGE, &ebt_ulog_logger);
+
+        return 0;
+
+out_target:
+        unregister_pernet_subsys(&ebt_ulog_net_ops);
+out_pernet:
+        return ret;
+}
+
+static void __exit ebt_ulog_fini(void)
+{
+        nf_log_unregister(&ebt_ulog_logger);
+        xt_unregister_target(&ebt_ulog_tg_reg);
+        unregister_pernet_subsys(&ebt_ulog_net_ops);
 }
 
 module_init(ebt_ulog_init);