*
* (C) 2001 by Jay Schulist <jschlst@samba.org>,
* (C) 2002-2005 by Harald Welte <laforge@gnumonks.org>
- * (C) 2005 by Pablo Neira Ayuso <pablo@eurodev.net>
+ * (C) 2005,2007 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* Initial netfilter messages via netlink development funded and
* generally made possible by Network Robots, Inc. (www.networkrobots.com)
#include <net/sock.h>
#include <net/netlink.h>
#include <linux/init.h>
-#include <linux/spinlock.h>
-#include <linux/netfilter.h>
#include <linux/netlink.h>
#include <linux/netfilter/nfnetlink.h>
static char __initdata nfversion[] = "0.30";
-#if 0
-#define DEBUGP(format, args...) \
- printk(KERN_DEBUG "%s(%d):%s(): " format, __FILE__, \
- __LINE__, __FUNCTION__, ## args)
-#else
-#define DEBUGP(format, args...)
-#endif
-
-static struct sock *nfnl = NULL;
-static struct nfnetlink_subsystem *subsys_table[NFNL_SUBSYS_COUNT];
+static const struct nfnetlink_subsystem *subsys_table[NFNL_SUBSYS_COUNT];
static DEFINE_MUTEX(nfnl_mutex);
-static void nfnl_lock(void)
+void nfnl_lock(void)
{
mutex_lock(&nfnl_mutex);
}
+EXPORT_SYMBOL_GPL(nfnl_lock);
-static int nfnl_trylock(void)
-{
- return !mutex_trylock(&nfnl_mutex);
-}
-
-static void __nfnl_unlock(void)
+void nfnl_unlock(void)
{
mutex_unlock(&nfnl_mutex);
}
+EXPORT_SYMBOL_GPL(nfnl_unlock);
-static void nfnl_unlock(void)
+int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n)
{
- mutex_unlock(&nfnl_mutex);
- if (nfnl->sk_receive_queue.qlen)
- nfnl->sk_data_ready(nfnl, 0);
-}
-
-int nfnetlink_subsys_register(struct nfnetlink_subsystem *n)
-{
- DEBUGP("registering subsystem ID %u\n", n->subsys_id);
-
nfnl_lock();
if (subsys_table[n->subsys_id]) {
nfnl_unlock();
return 0;
}
+EXPORT_SYMBOL_GPL(nfnetlink_subsys_register);
-int nfnetlink_subsys_unregister(struct nfnetlink_subsystem *n)
+int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n)
{
- DEBUGP("unregistering subsystem ID %u\n", n->subsys_id);
-
nfnl_lock();
subsys_table[n->subsys_id] = NULL;
nfnl_unlock();
return 0;
}
+EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister);
-static inline struct nfnetlink_subsystem *nfnetlink_get_subsys(u_int16_t type)
+static inline const struct nfnetlink_subsystem *nfnetlink_get_subsys(u_int16_t type)
{
u_int8_t subsys_id = NFNL_SUBSYS_ID(type);
- if (subsys_id >= NFNL_SUBSYS_COUNT
- || subsys_table[subsys_id] == NULL)
+ if (subsys_id >= NFNL_SUBSYS_COUNT)
return NULL;
return subsys_table[subsys_id];
}
-static inline struct nfnl_callback *
-nfnetlink_find_client(u_int16_t type, struct nfnetlink_subsystem *ss)
+static inline const struct nfnl_callback *
+nfnetlink_find_client(u_int16_t type, const struct nfnetlink_subsystem *ss)
{
u_int8_t cb_id = NFNL_MSG_TYPE(type);
- if (cb_id >= ss->cb_count) {
- DEBUGP("msgtype %u >= %u, returning\n", type, ss->cb_count);
+ if (cb_id >= ss->cb_count)
return NULL;
- }
return &ss->cb[cb_id];
}
-void __nfa_fill(struct sk_buff *skb, int attrtype, int attrlen,
- const void *data)
+int nfnetlink_has_listeners(struct net *net, unsigned int group)
{
- struct nfattr *nfa;
- int size = NFA_LENGTH(attrlen);
-
- nfa = (struct nfattr *)skb_put(skb, NFA_ALIGN(size));
- nfa->nfa_type = attrtype;
- nfa->nfa_len = size;
- memcpy(NFA_DATA(nfa), data, attrlen);
- memset(NFA_DATA(nfa) + attrlen, 0, NFA_ALIGN(size) - size);
-}
-
-void nfattr_parse(struct nfattr *tb[], int maxattr, struct nfattr *nfa, int len)
-{
- memset(tb, 0, sizeof(struct nfattr *) * maxattr);
-
- while (NFA_OK(nfa, len)) {
- unsigned flavor = NFA_TYPE(nfa);
- if (flavor && flavor <= maxattr)
- tb[flavor-1] = nfa;
- nfa = NFA_NEXT(nfa, len);
- }
-}
-
-/**
- * nfnetlink_check_attributes - check and parse nfnetlink attributes
- *
- * subsys: nfnl subsystem for which this message is to be parsed
- * nlmsghdr: netlink message to be checked/parsed
- * cda: array of pointers, needs to be at least subsys->attr_count big
- *
- */
-static int
-nfnetlink_check_attributes(struct nfnetlink_subsystem *subsys,
- struct nlmsghdr *nlh, struct nfattr *cda[])
-{
- int min_len;
- u_int16_t attr_count;
- u_int8_t cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
-
- if (unlikely(cb_id >= subsys->cb_count)) {
- DEBUGP("msgtype %u >= %u, returning\n",
- cb_id, subsys->cb_count);
- return -EINVAL;
- }
-
- min_len = NLMSG_SPACE(sizeof(struct nfgenmsg));
- if (unlikely(nlh->nlmsg_len < min_len))
- return -EINVAL;
-
- attr_count = subsys->cb[cb_id].attr_count;
- memset(cda, 0, sizeof(struct nfattr *) * attr_count);
-
- /* check attribute lengths. */
- if (likely(nlh->nlmsg_len > min_len)) {
- struct nfattr *attr = NFM_NFA(NLMSG_DATA(nlh));
- int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
-
- while (NFA_OK(attr, attrlen)) {
- unsigned flavor = NFA_TYPE(attr);
- if (flavor) {
- if (flavor > attr_count)
- return -EINVAL;
- cda[flavor - 1] = attr;
- }
- attr = NFA_NEXT(attr, attrlen);
- }
- }
-
- /* implicit: if nlmsg_len == min_len, we return 0, and an empty
- * (zeroed) cda[] array. The message is valid, but empty. */
-
- return 0;
+ return netlink_has_listeners(net->nfnl, group);
}
+EXPORT_SYMBOL_GPL(nfnetlink_has_listeners);
-int nfnetlink_has_listeners(unsigned int group)
+int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 pid,
+ unsigned group, int echo, gfp_t flags)
{
- return netlink_has_listeners(nfnl, group);
+ return nlmsg_notify(net->nfnl, skb, pid, group, echo, flags);
}
-EXPORT_SYMBOL_GPL(nfnetlink_has_listeners);
+EXPORT_SYMBOL_GPL(nfnetlink_send);
-int nfnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
+void nfnetlink_set_err(struct net *net, u32 pid, u32 group, int error)
{
- int err = 0;
-
- NETLINK_CB(skb).dst_group = group;
- if (echo)
- atomic_inc(&skb->users);
- netlink_broadcast(nfnl, skb, pid, group, gfp_any());
- if (echo)
- err = netlink_unicast(nfnl, skb, pid, MSG_DONTWAIT);
-
- return err;
+ netlink_set_err(net->nfnl, pid, group, error);
}
+EXPORT_SYMBOL_GPL(nfnetlink_set_err);
-int nfnetlink_unicast(struct sk_buff *skb, u_int32_t pid, int flags)
+int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u_int32_t pid, int flags)
{
- return netlink_unicast(nfnl, skb, pid, flags);
+ return netlink_unicast(net->nfnl, skb, pid, flags);
}
+EXPORT_SYMBOL_GPL(nfnetlink_unicast);
/* Process one complete nfnetlink message. */
-static int nfnetlink_rcv_msg(struct sk_buff *skb,
- struct nlmsghdr *nlh, int *errp)
+static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
{
- struct nfnl_callback *nc;
- struct nfnetlink_subsystem *ss;
- int type, err = 0;
-
- DEBUGP("entered; subsys=%u, msgtype=%u\n",
- NFNL_SUBSYS_ID(nlh->nlmsg_type),
- NFNL_MSG_TYPE(nlh->nlmsg_type));
-
- if (security_netlink_recv(skb, CAP_NET_ADMIN)) {
- DEBUGP("missing CAP_NET_ADMIN\n");
- *errp = -EPERM;
- return -1;
- }
+ struct net *net = sock_net(skb->sk);
+ const struct nfnl_callback *nc;
+ const struct nfnetlink_subsystem *ss;
+ int type, err;
- /* Only requests are handled by kernel now. */
- if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) {
- DEBUGP("received non-request message\n");
- return 0;
- }
+ if (security_netlink_recv(skb, CAP_NET_ADMIN))
+ return -EPERM;
/* All the messages must at least contain nfgenmsg */
- if (nlh->nlmsg_len < NLMSG_SPACE(sizeof(struct nfgenmsg))) {
- DEBUGP("received message was too short\n");
+ if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct nfgenmsg)))
return 0;
- }
type = nlh->nlmsg_type;
+replay:
ss = nfnetlink_get_subsys(type);
if (!ss) {
-#ifdef CONFIG_KMOD
- /* don't call nfnl_unlock, since it would reenter
- * with further packet processing */
- __nfnl_unlock();
+#ifdef CONFIG_MODULES
+ nfnl_unlock();
request_module("nfnetlink-subsys-%d", NFNL_SUBSYS_ID(type));
nfnl_lock();
ss = nfnetlink_get_subsys(type);
if (!ss)
#endif
- goto err_inval;
+ return -EINVAL;
}
nc = nfnetlink_find_client(type, ss);
- if (!nc) {
- DEBUGP("unable to find client for type %d\n", type);
- goto err_inval;
- }
+ if (!nc)
+ return -EINVAL;
{
- u_int16_t attr_count =
- ss->cb[NFNL_MSG_TYPE(nlh->nlmsg_type)].attr_count;
- struct nfattr *cda[attr_count];
-
- memset(cda, 0, sizeof(struct nfattr *) * attr_count);
-
- err = nfnetlink_check_attributes(ss, nlh, cda);
+ int min_len = NLMSG_SPACE(sizeof(struct nfgenmsg));
+ u_int8_t cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
+ struct nlattr *cda[ss->cb[cb_id].attr_count + 1];
+ struct nlattr *attr = (void *)nlh + min_len;
+ int attrlen = nlh->nlmsg_len - min_len;
+
+ err = nla_parse(cda, ss->cb[cb_id].attr_count,
+ attr, attrlen, ss->cb[cb_id].policy);
if (err < 0)
- goto err_inval;
+ return err;
- DEBUGP("calling handler\n");
- err = nc->call(nfnl, skb, nlh, cda, errp);
- *errp = err;
+ err = nc->call(net->nfnl, skb, nlh, (const struct nlattr **)cda);
+ if (err == -EAGAIN)
+ goto replay;
return err;
}
+}
-err_inval:
- DEBUGP("returning -EINVAL\n");
- *errp = -EINVAL;
- return -1;
+static void nfnetlink_rcv(struct sk_buff *skb)
+{
+ nfnl_lock();
+ netlink_rcv_skb(skb, &nfnetlink_rcv_msg);
+ nfnl_unlock();
}
-/* Process one packet of messages. */
-static inline int nfnetlink_rcv_skb(struct sk_buff *skb)
+static int __net_init nfnetlink_net_init(struct net *net)
{
- int err;
- struct nlmsghdr *nlh;
-
- while (skb->len >= NLMSG_SPACE(0)) {
- u32 rlen;
-
- nlh = (struct nlmsghdr *)skb->data;
- if (nlh->nlmsg_len < sizeof(struct nlmsghdr)
- || skb->len < nlh->nlmsg_len)
- return 0;
- rlen = NLMSG_ALIGN(nlh->nlmsg_len);
- if (rlen > skb->len)
- rlen = skb->len;
- if (nfnetlink_rcv_msg(skb, nlh, &err)) {
- if (!err)
- return -1;
- netlink_ack(skb, nlh, err);
- } else
- if (nlh->nlmsg_flags & NLM_F_ACK)
- netlink_ack(skb, nlh, 0);
- skb_pull(skb, rlen);
- }
+ struct sock *nfnl;
+ nfnl = netlink_kernel_create(net, NETLINK_NETFILTER, NFNLGRP_MAX,
+ nfnetlink_rcv, NULL, THIS_MODULE);
+ if (!nfnl)
+ return -ENOMEM;
+ net->nfnl_stash = nfnl;
+ rcu_assign_pointer(net->nfnl, nfnl);
return 0;
}
-static void nfnetlink_rcv(struct sock *sk, int len)
+static void __net_exit nfnetlink_net_exit_batch(struct list_head *net_exit_list)
{
- do {
- struct sk_buff *skb;
-
- if (nfnl_trylock())
- return;
-
- while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
- if (nfnetlink_rcv_skb(skb)) {
- if (skb->len)
- skb_queue_head(&sk->sk_receive_queue,
- skb);
- else
- kfree_skb(skb);
- break;
- }
- kfree_skb(skb);
- }
-
- /* don't call nfnl_unlock, since it would reenter
- * with further packet processing */
- __nfnl_unlock();
- } while(nfnl && nfnl->sk_receive_queue.qlen);
-}
+ struct net *net;
-static void __exit nfnetlink_exit(void)
-{
- printk("Removing netfilter NETLINK layer.\n");
- sock_release(nfnl->sk_socket);
- return;
+ list_for_each_entry(net, net_exit_list, exit_list)
+ rcu_assign_pointer(net->nfnl, NULL);
+ synchronize_net();
+ list_for_each_entry(net, net_exit_list, exit_list)
+ netlink_kernel_release(net->nfnl_stash);
}
+static struct pernet_operations nfnetlink_net_ops = {
+ .init = nfnetlink_net_init,
+ .exit_batch = nfnetlink_net_exit_batch,
+};
+
static int __init nfnetlink_init(void)
{
printk("Netfilter messages via NETLINK v%s.\n", nfversion);
-
- nfnl = netlink_kernel_create(NETLINK_NETFILTER, NFNLGRP_MAX,
- nfnetlink_rcv, THIS_MODULE);
- if (!nfnl) {
- printk(KERN_ERR "cannot initialize nfnetlink!\n");
- return -1;
- }
-
- return 0;
+ return register_pernet_subsys(&nfnetlink_net_ops);
}
+static void __exit nfnetlink_exit(void)
+{
+ printk("Removing netfilter NETLINK layer.\n");
+ unregister_pernet_subsys(&nfnetlink_net_ops);
+}
module_init(nfnetlink_init);
module_exit(nfnetlink_exit);
-
-EXPORT_SYMBOL_GPL(nfnetlink_subsys_register);
-EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister);
-EXPORT_SYMBOL_GPL(nfnetlink_send);
-EXPORT_SYMBOL_GPL(nfnetlink_unicast);
-EXPORT_SYMBOL_GPL(nfattr_parse);
-EXPORT_SYMBOL_GPL(__nfa_fill);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff