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731 lines
18 KiB
731 lines
18 KiB
/* Netfilter messages via netlink socket. Allows for user space |
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* protocol helpers and general trouble making from userspace. |
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* |
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* (C) 2001 by Jay Schulist <[email protected]>, |
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* (C) 2002-2005 by Harald Welte <[email protected]> |
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* (C) 2005-2017 by Pablo Neira Ayuso <[email protected]> |
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* |
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* Initial netfilter messages via netlink development funded and |
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* generally made possible by Network Robots, Inc. (www.networkrobots.com) |
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* |
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* Further development of this code funded by Astaro AG (http://www.astaro.com) |
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* |
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* This software may be used and distributed according to the terms |
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* of the GNU General Public License, incorporated herein by reference. |
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*/ |
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|
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#include <linux/module.h> |
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#include <linux/types.h> |
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#include <linux/socket.h> |
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#include <linux/kernel.h> |
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#include <linux/string.h> |
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#include <linux/sockios.h> |
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#include <linux/net.h> |
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#include <linux/skbuff.h> |
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#include <linux/uaccess.h> |
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#include <net/sock.h> |
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#include <linux/init.h> |
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#include <linux/sched/signal.h> |
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|
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#include <net/netlink.h> |
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#include <net/netns/generic.h> |
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#include <linux/netfilter/nfnetlink.h> |
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|
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MODULE_LICENSE("GPL"); |
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MODULE_AUTHOR("Harald Welte <[email protected]>"); |
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MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER); |
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MODULE_DESCRIPTION("Netfilter messages via netlink socket"); |
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|
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#define nfnl_dereference_protected(id) \ |
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rcu_dereference_protected(table[(id)].subsys, \ |
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lockdep_nfnl_is_held((id))) |
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|
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#define NFNL_MAX_ATTR_COUNT 32 |
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|
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static unsigned int nfnetlink_pernet_id __read_mostly; |
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|
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struct nfnl_net { |
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struct sock *nfnl; |
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}; |
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|
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static struct { |
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struct mutex mutex; |
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const struct nfnetlink_subsystem __rcu *subsys; |
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} table[NFNL_SUBSYS_COUNT]; |
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|
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static struct lock_class_key nfnl_lockdep_keys[NFNL_SUBSYS_COUNT]; |
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|
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static const char *const nfnl_lockdep_names[NFNL_SUBSYS_COUNT] = { |
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[NFNL_SUBSYS_NONE] = "nfnl_subsys_none", |
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[NFNL_SUBSYS_CTNETLINK] = "nfnl_subsys_ctnetlink", |
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[NFNL_SUBSYS_CTNETLINK_EXP] = "nfnl_subsys_ctnetlink_exp", |
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[NFNL_SUBSYS_QUEUE] = "nfnl_subsys_queue", |
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[NFNL_SUBSYS_ULOG] = "nfnl_subsys_ulog", |
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[NFNL_SUBSYS_OSF] = "nfnl_subsys_osf", |
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[NFNL_SUBSYS_IPSET] = "nfnl_subsys_ipset", |
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[NFNL_SUBSYS_ACCT] = "nfnl_subsys_acct", |
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[NFNL_SUBSYS_CTNETLINK_TIMEOUT] = "nfnl_subsys_cttimeout", |
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[NFNL_SUBSYS_CTHELPER] = "nfnl_subsys_cthelper", |
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[NFNL_SUBSYS_NFTABLES] = "nfnl_subsys_nftables", |
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[NFNL_SUBSYS_NFT_COMPAT] = "nfnl_subsys_nftcompat", |
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[NFNL_SUBSYS_HOOK] = "nfnl_subsys_hook", |
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}; |
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|
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static const int nfnl_group2type[NFNLGRP_MAX+1] = { |
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[NFNLGRP_CONNTRACK_NEW] = NFNL_SUBSYS_CTNETLINK, |
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[NFNLGRP_CONNTRACK_UPDATE] = NFNL_SUBSYS_CTNETLINK, |
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[NFNLGRP_CONNTRACK_DESTROY] = NFNL_SUBSYS_CTNETLINK, |
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[NFNLGRP_CONNTRACK_EXP_NEW] = NFNL_SUBSYS_CTNETLINK_EXP, |
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[NFNLGRP_CONNTRACK_EXP_UPDATE] = NFNL_SUBSYS_CTNETLINK_EXP, |
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[NFNLGRP_CONNTRACK_EXP_DESTROY] = NFNL_SUBSYS_CTNETLINK_EXP, |
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[NFNLGRP_NFTABLES] = NFNL_SUBSYS_NFTABLES, |
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[NFNLGRP_ACCT_QUOTA] = NFNL_SUBSYS_ACCT, |
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[NFNLGRP_NFTRACE] = NFNL_SUBSYS_NFTABLES, |
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}; |
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|
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static struct nfnl_net *nfnl_pernet(struct net *net) |
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{ |
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return net_generic(net, nfnetlink_pernet_id); |
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} |
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|
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void nfnl_lock(__u8 subsys_id) |
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{ |
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mutex_lock(&table[subsys_id].mutex); |
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} |
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EXPORT_SYMBOL_GPL(nfnl_lock); |
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|
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void nfnl_unlock(__u8 subsys_id) |
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{ |
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mutex_unlock(&table[subsys_id].mutex); |
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} |
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EXPORT_SYMBOL_GPL(nfnl_unlock); |
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|
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#ifdef CONFIG_PROVE_LOCKING |
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bool lockdep_nfnl_is_held(u8 subsys_id) |
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{ |
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return lockdep_is_held(&table[subsys_id].mutex); |
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} |
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EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held); |
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#endif |
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|
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int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n) |
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{ |
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u8 cb_id; |
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|
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/* Sanity-check attr_count size to avoid stack buffer overflow. */ |
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for (cb_id = 0; cb_id < n->cb_count; cb_id++) |
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if (WARN_ON(n->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT)) |
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return -EINVAL; |
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|
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nfnl_lock(n->subsys_id); |
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if (table[n->subsys_id].subsys) { |
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nfnl_unlock(n->subsys_id); |
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return -EBUSY; |
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} |
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rcu_assign_pointer(table[n->subsys_id].subsys, n); |
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nfnl_unlock(n->subsys_id); |
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|
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return 0; |
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} |
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EXPORT_SYMBOL_GPL(nfnetlink_subsys_register); |
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|
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int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n) |
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{ |
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nfnl_lock(n->subsys_id); |
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table[n->subsys_id].subsys = NULL; |
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nfnl_unlock(n->subsys_id); |
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synchronize_rcu(); |
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return 0; |
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} |
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EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister); |
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|
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static inline const struct nfnetlink_subsystem *nfnetlink_get_subsys(u16 type) |
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{ |
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u8 subsys_id = NFNL_SUBSYS_ID(type); |
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|
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if (subsys_id >= NFNL_SUBSYS_COUNT) |
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return NULL; |
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|
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return rcu_dereference(table[subsys_id].subsys); |
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} |
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|
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static inline const struct nfnl_callback * |
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nfnetlink_find_client(u16 type, const struct nfnetlink_subsystem *ss) |
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{ |
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u8 cb_id = NFNL_MSG_TYPE(type); |
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|
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if (cb_id >= ss->cb_count) |
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return NULL; |
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|
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return &ss->cb[cb_id]; |
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} |
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|
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int nfnetlink_has_listeners(struct net *net, unsigned int group) |
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{ |
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struct nfnl_net *nfnlnet = nfnl_pernet(net); |
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|
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return netlink_has_listeners(nfnlnet->nfnl, group); |
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} |
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EXPORT_SYMBOL_GPL(nfnetlink_has_listeners); |
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|
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int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid, |
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unsigned int group, int echo, gfp_t flags) |
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{ |
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struct nfnl_net *nfnlnet = nfnl_pernet(net); |
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|
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return nlmsg_notify(nfnlnet->nfnl, skb, portid, group, echo, flags); |
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} |
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EXPORT_SYMBOL_GPL(nfnetlink_send); |
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|
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int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error) |
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{ |
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struct nfnl_net *nfnlnet = nfnl_pernet(net); |
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|
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return netlink_set_err(nfnlnet->nfnl, portid, group, error); |
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} |
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EXPORT_SYMBOL_GPL(nfnetlink_set_err); |
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int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid) |
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{ |
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struct nfnl_net *nfnlnet = nfnl_pernet(net); |
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int err; |
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|
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err = nlmsg_unicast(nfnlnet->nfnl, skb, portid); |
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if (err == -EAGAIN) |
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err = -ENOBUFS; |
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|
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return err; |
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} |
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EXPORT_SYMBOL_GPL(nfnetlink_unicast); |
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|
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void nfnetlink_broadcast(struct net *net, struct sk_buff *skb, __u32 portid, |
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__u32 group, gfp_t allocation) |
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{ |
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struct nfnl_net *nfnlnet = nfnl_pernet(net); |
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|
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netlink_broadcast(nfnlnet->nfnl, skb, portid, group, allocation); |
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} |
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EXPORT_SYMBOL_GPL(nfnetlink_broadcast); |
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|
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/* Process one complete nfnetlink message. */ |
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static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, |
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struct netlink_ext_ack *extack) |
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{ |
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struct net *net = sock_net(skb->sk); |
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const struct nfnl_callback *nc; |
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const struct nfnetlink_subsystem *ss; |
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int type, err; |
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|
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/* All the messages must at least contain nfgenmsg */ |
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if (nlmsg_len(nlh) < sizeof(struct nfgenmsg)) |
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return 0; |
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type = nlh->nlmsg_type; |
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replay: |
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rcu_read_lock(); |
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ss = nfnetlink_get_subsys(type); |
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if (!ss) { |
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#ifdef CONFIG_MODULES |
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rcu_read_unlock(); |
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request_module("nfnetlink-subsys-%d", NFNL_SUBSYS_ID(type)); |
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rcu_read_lock(); |
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ss = nfnetlink_get_subsys(type); |
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if (!ss) |
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#endif |
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{ |
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rcu_read_unlock(); |
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return -EINVAL; |
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} |
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} |
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nc = nfnetlink_find_client(type, ss); |
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if (!nc) { |
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rcu_read_unlock(); |
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return -EINVAL; |
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} |
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|
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{ |
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int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
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struct nfnl_net *nfnlnet = nfnl_pernet(net); |
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u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); |
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struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; |
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struct nlattr *attr = (void *)nlh + min_len; |
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int attrlen = nlh->nlmsg_len - min_len; |
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__u8 subsys_id = NFNL_SUBSYS_ID(type); |
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struct nfnl_info info = { |
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.net = net, |
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.sk = nfnlnet->nfnl, |
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.nlh = nlh, |
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.nfmsg = nlmsg_data(nlh), |
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.extack = extack, |
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}; |
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|
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/* Sanity-check NFNL_MAX_ATTR_COUNT */ |
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if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { |
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rcu_read_unlock(); |
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return -ENOMEM; |
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} |
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|
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err = nla_parse_deprecated(cda, ss->cb[cb_id].attr_count, |
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attr, attrlen, |
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ss->cb[cb_id].policy, extack); |
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if (err < 0) { |
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rcu_read_unlock(); |
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return err; |
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} |
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|
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if (!nc->call) { |
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rcu_read_unlock(); |
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return -EINVAL; |
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} |
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switch (nc->type) { |
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case NFNL_CB_RCU: |
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err = nc->call(skb, &info, (const struct nlattr **)cda); |
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rcu_read_unlock(); |
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break; |
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case NFNL_CB_MUTEX: |
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rcu_read_unlock(); |
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nfnl_lock(subsys_id); |
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if (nfnl_dereference_protected(subsys_id) != ss || |
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nfnetlink_find_client(type, ss) != nc) { |
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err = -EAGAIN; |
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break; |
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} |
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err = nc->call(skb, &info, (const struct nlattr **)cda); |
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nfnl_unlock(subsys_id); |
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break; |
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default: |
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rcu_read_unlock(); |
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err = -EINVAL; |
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break; |
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} |
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if (err == -EAGAIN) |
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goto replay; |
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return err; |
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} |
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} |
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|
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struct nfnl_err { |
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struct list_head head; |
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struct nlmsghdr *nlh; |
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int err; |
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struct netlink_ext_ack extack; |
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}; |
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|
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static int nfnl_err_add(struct list_head *list, struct nlmsghdr *nlh, int err, |
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const struct netlink_ext_ack *extack) |
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{ |
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struct nfnl_err *nfnl_err; |
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|
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nfnl_err = kmalloc(sizeof(struct nfnl_err), GFP_KERNEL); |
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if (nfnl_err == NULL) |
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return -ENOMEM; |
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|
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nfnl_err->nlh = nlh; |
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nfnl_err->err = err; |
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nfnl_err->extack = *extack; |
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list_add_tail(&nfnl_err->head, list); |
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|
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return 0; |
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} |
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|
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static void nfnl_err_del(struct nfnl_err *nfnl_err) |
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{ |
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list_del(&nfnl_err->head); |
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kfree(nfnl_err); |
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} |
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|
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static void nfnl_err_reset(struct list_head *err_list) |
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{ |
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struct nfnl_err *nfnl_err, *next; |
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|
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list_for_each_entry_safe(nfnl_err, next, err_list, head) |
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nfnl_err_del(nfnl_err); |
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} |
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|
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static void nfnl_err_deliver(struct list_head *err_list, struct sk_buff *skb) |
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{ |
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struct nfnl_err *nfnl_err, *next; |
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|
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list_for_each_entry_safe(nfnl_err, next, err_list, head) { |
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netlink_ack(skb, nfnl_err->nlh, nfnl_err->err, |
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&nfnl_err->extack); |
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nfnl_err_del(nfnl_err); |
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} |
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} |
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|
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enum { |
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NFNL_BATCH_FAILURE = (1 << 0), |
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NFNL_BATCH_DONE = (1 << 1), |
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NFNL_BATCH_REPLAY = (1 << 2), |
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}; |
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|
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static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh, |
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u16 subsys_id, u32 genid) |
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{ |
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struct sk_buff *oskb = skb; |
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struct net *net = sock_net(skb->sk); |
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const struct nfnetlink_subsystem *ss; |
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const struct nfnl_callback *nc; |
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struct netlink_ext_ack extack; |
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LIST_HEAD(err_list); |
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u32 status; |
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int err; |
|
|
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if (subsys_id >= NFNL_SUBSYS_COUNT) |
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return netlink_ack(skb, nlh, -EINVAL, NULL); |
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replay: |
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status = 0; |
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replay_abort: |
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skb = netlink_skb_clone(oskb, GFP_KERNEL); |
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if (!skb) |
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return netlink_ack(oskb, nlh, -ENOMEM, NULL); |
|
|
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nfnl_lock(subsys_id); |
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ss = nfnl_dereference_protected(subsys_id); |
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if (!ss) { |
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#ifdef CONFIG_MODULES |
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nfnl_unlock(subsys_id); |
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request_module("nfnetlink-subsys-%d", subsys_id); |
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nfnl_lock(subsys_id); |
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ss = nfnl_dereference_protected(subsys_id); |
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if (!ss) |
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#endif |
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{ |
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nfnl_unlock(subsys_id); |
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netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); |
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return kfree_skb(skb); |
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} |
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} |
|
|
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if (!ss->valid_genid || !ss->commit || !ss->abort) { |
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nfnl_unlock(subsys_id); |
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netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); |
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return kfree_skb(skb); |
|
} |
|
|
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if (!try_module_get(ss->owner)) { |
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nfnl_unlock(subsys_id); |
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netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); |
|
return kfree_skb(skb); |
|
} |
|
|
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if (!ss->valid_genid(net, genid)) { |
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module_put(ss->owner); |
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nfnl_unlock(subsys_id); |
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netlink_ack(oskb, nlh, -ERESTART, NULL); |
|
return kfree_skb(skb); |
|
} |
|
|
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nfnl_unlock(subsys_id); |
|
|
|
while (skb->len >= nlmsg_total_size(0)) { |
|
int msglen, type; |
|
|
|
if (fatal_signal_pending(current)) { |
|
nfnl_err_reset(&err_list); |
|
err = -EINTR; |
|
status = NFNL_BATCH_FAILURE; |
|
goto done; |
|
} |
|
|
|
memset(&extack, 0, sizeof(extack)); |
|
nlh = nlmsg_hdr(skb); |
|
err = 0; |
|
|
|
if (nlh->nlmsg_len < NLMSG_HDRLEN || |
|
skb->len < nlh->nlmsg_len || |
|
nlmsg_len(nlh) < sizeof(struct nfgenmsg)) { |
|
nfnl_err_reset(&err_list); |
|
status |= NFNL_BATCH_FAILURE; |
|
goto done; |
|
} |
|
|
|
/* Only requests are handled by the kernel */ |
|
if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) { |
|
err = -EINVAL; |
|
goto ack; |
|
} |
|
|
|
type = nlh->nlmsg_type; |
|
if (type == NFNL_MSG_BATCH_BEGIN) { |
|
/* Malformed: Batch begin twice */ |
|
nfnl_err_reset(&err_list); |
|
status |= NFNL_BATCH_FAILURE; |
|
goto done; |
|
} else if (type == NFNL_MSG_BATCH_END) { |
|
status |= NFNL_BATCH_DONE; |
|
goto done; |
|
} else if (type < NLMSG_MIN_TYPE) { |
|
err = -EINVAL; |
|
goto ack; |
|
} |
|
|
|
/* We only accept a batch with messages for the same |
|
* subsystem. |
|
*/ |
|
if (NFNL_SUBSYS_ID(type) != subsys_id) { |
|
err = -EINVAL; |
|
goto ack; |
|
} |
|
|
|
nc = nfnetlink_find_client(type, ss); |
|
if (!nc) { |
|
err = -EINVAL; |
|
goto ack; |
|
} |
|
|
|
if (nc->type != NFNL_CB_BATCH) { |
|
err = -EINVAL; |
|
goto ack; |
|
} |
|
|
|
{ |
|
int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
|
struct nfnl_net *nfnlnet = nfnl_pernet(net); |
|
struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; |
|
struct nlattr *attr = (void *)nlh + min_len; |
|
u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); |
|
int attrlen = nlh->nlmsg_len - min_len; |
|
struct nfnl_info info = { |
|
.net = net, |
|
.sk = nfnlnet->nfnl, |
|
.nlh = nlh, |
|
.nfmsg = nlmsg_data(nlh), |
|
.extack = &extack, |
|
}; |
|
|
|
/* Sanity-check NFTA_MAX_ATTR */ |
|
if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { |
|
err = -ENOMEM; |
|
goto ack; |
|
} |
|
|
|
err = nla_parse_deprecated(cda, |
|
ss->cb[cb_id].attr_count, |
|
attr, attrlen, |
|
ss->cb[cb_id].policy, NULL); |
|
if (err < 0) |
|
goto ack; |
|
|
|
err = nc->call(skb, &info, (const struct nlattr **)cda); |
|
|
|
/* The lock was released to autoload some module, we |
|
* have to abort and start from scratch using the |
|
* original skb. |
|
*/ |
|
if (err == -EAGAIN) { |
|
status |= NFNL_BATCH_REPLAY; |
|
goto done; |
|
} |
|
} |
|
ack: |
|
if (nlh->nlmsg_flags & NLM_F_ACK || err) { |
|
/* Errors are delivered once the full batch has been |
|
* processed, this avoids that the same error is |
|
* reported several times when replaying the batch. |
|
*/ |
|
if (nfnl_err_add(&err_list, nlh, err, &extack) < 0) { |
|
/* We failed to enqueue an error, reset the |
|
* list of errors and send OOM to userspace |
|
* pointing to the batch header. |
|
*/ |
|
nfnl_err_reset(&err_list); |
|
netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM, |
|
NULL); |
|
status |= NFNL_BATCH_FAILURE; |
|
goto done; |
|
} |
|
/* We don't stop processing the batch on errors, thus, |
|
* userspace gets all the errors that the batch |
|
* triggers. |
|
*/ |
|
if (err) |
|
status |= NFNL_BATCH_FAILURE; |
|
} |
|
|
|
msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
|
if (msglen > skb->len) |
|
msglen = skb->len; |
|
skb_pull(skb, msglen); |
|
} |
|
done: |
|
if (status & NFNL_BATCH_REPLAY) { |
|
ss->abort(net, oskb, NFNL_ABORT_AUTOLOAD); |
|
nfnl_err_reset(&err_list); |
|
kfree_skb(skb); |
|
module_put(ss->owner); |
|
goto replay; |
|
} else if (status == NFNL_BATCH_DONE) { |
|
err = ss->commit(net, oskb); |
|
if (err == -EAGAIN) { |
|
status |= NFNL_BATCH_REPLAY; |
|
goto done; |
|
} else if (err) { |
|
ss->abort(net, oskb, NFNL_ABORT_NONE); |
|
netlink_ack(oskb, nlmsg_hdr(oskb), err, NULL); |
|
} |
|
} else { |
|
enum nfnl_abort_action abort_action; |
|
|
|
if (status & NFNL_BATCH_FAILURE) |
|
abort_action = NFNL_ABORT_NONE; |
|
else |
|
abort_action = NFNL_ABORT_VALIDATE; |
|
|
|
err = ss->abort(net, oskb, abort_action); |
|
if (err == -EAGAIN) { |
|
nfnl_err_reset(&err_list); |
|
kfree_skb(skb); |
|
module_put(ss->owner); |
|
status |= NFNL_BATCH_FAILURE; |
|
goto replay_abort; |
|
} |
|
} |
|
if (ss->cleanup) |
|
ss->cleanup(net); |
|
|
|
nfnl_err_deliver(&err_list, oskb); |
|
kfree_skb(skb); |
|
module_put(ss->owner); |
|
} |
|
|
|
static const struct nla_policy nfnl_batch_policy[NFNL_BATCH_MAX + 1] = { |
|
[NFNL_BATCH_GENID] = { .type = NLA_U32 }, |
|
}; |
|
|
|
static void nfnetlink_rcv_skb_batch(struct sk_buff *skb, struct nlmsghdr *nlh) |
|
{ |
|
int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
|
struct nlattr *attr = (void *)nlh + min_len; |
|
struct nlattr *cda[NFNL_BATCH_MAX + 1]; |
|
int attrlen = nlh->nlmsg_len - min_len; |
|
struct nfgenmsg *nfgenmsg; |
|
int msglen, err; |
|
u32 gen_id = 0; |
|
u16 res_id; |
|
|
|
msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
|
if (msglen > skb->len) |
|
msglen = skb->len; |
|
|
|
if (skb->len < NLMSG_HDRLEN + sizeof(struct nfgenmsg)) |
|
return; |
|
|
|
err = nla_parse_deprecated(cda, NFNL_BATCH_MAX, attr, attrlen, |
|
nfnl_batch_policy, NULL); |
|
if (err < 0) { |
|
netlink_ack(skb, nlh, err, NULL); |
|
return; |
|
} |
|
if (cda[NFNL_BATCH_GENID]) |
|
gen_id = ntohl(nla_get_be32(cda[NFNL_BATCH_GENID])); |
|
|
|
nfgenmsg = nlmsg_data(nlh); |
|
skb_pull(skb, msglen); |
|
/* Work around old nft using host byte order */ |
|
if (nfgenmsg->res_id == NFNL_SUBSYS_NFTABLES) |
|
res_id = NFNL_SUBSYS_NFTABLES; |
|
else |
|
res_id = ntohs(nfgenmsg->res_id); |
|
|
|
nfnetlink_rcv_batch(skb, nlh, res_id, gen_id); |
|
} |
|
|
|
static void nfnetlink_rcv(struct sk_buff *skb) |
|
{ |
|
struct nlmsghdr *nlh = nlmsg_hdr(skb); |
|
|
|
if (skb->len < NLMSG_HDRLEN || |
|
nlh->nlmsg_len < NLMSG_HDRLEN || |
|
skb->len < nlh->nlmsg_len) |
|
return; |
|
|
|
if (!netlink_net_capable(skb, CAP_NET_ADMIN)) { |
|
netlink_ack(skb, nlh, -EPERM, NULL); |
|
return; |
|
} |
|
|
|
if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN) |
|
nfnetlink_rcv_skb_batch(skb, nlh); |
|
else |
|
netlink_rcv_skb(skb, nfnetlink_rcv_msg); |
|
} |
|
|
|
#ifdef CONFIG_MODULES |
|
static int nfnetlink_bind(struct net *net, int group) |
|
{ |
|
const struct nfnetlink_subsystem *ss; |
|
int type; |
|
|
|
if (group <= NFNLGRP_NONE || group > NFNLGRP_MAX) |
|
return 0; |
|
|
|
type = nfnl_group2type[group]; |
|
|
|
rcu_read_lock(); |
|
ss = nfnetlink_get_subsys(type << 8); |
|
rcu_read_unlock(); |
|
if (!ss) |
|
request_module_nowait("nfnetlink-subsys-%d", type); |
|
return 0; |
|
} |
|
#endif |
|
|
|
static int __net_init nfnetlink_net_init(struct net *net) |
|
{ |
|
struct nfnl_net *nfnlnet = nfnl_pernet(net); |
|
struct netlink_kernel_cfg cfg = { |
|
.groups = NFNLGRP_MAX, |
|
.input = nfnetlink_rcv, |
|
#ifdef CONFIG_MODULES |
|
.bind = nfnetlink_bind, |
|
#endif |
|
}; |
|
|
|
nfnlnet->nfnl = netlink_kernel_create(net, NETLINK_NETFILTER, &cfg); |
|
if (!nfnlnet->nfnl) |
|
return -ENOMEM; |
|
return 0; |
|
} |
|
|
|
static void __net_exit nfnetlink_net_exit_batch(struct list_head *net_exit_list) |
|
{ |
|
struct nfnl_net *nfnlnet; |
|
struct net *net; |
|
|
|
list_for_each_entry(net, net_exit_list, exit_list) { |
|
nfnlnet = nfnl_pernet(net); |
|
|
|
netlink_kernel_release(nfnlnet->nfnl); |
|
} |
|
} |
|
|
|
static struct pernet_operations nfnetlink_net_ops = { |
|
.init = nfnetlink_net_init, |
|
.exit_batch = nfnetlink_net_exit_batch, |
|
.id = &nfnetlink_pernet_id, |
|
.size = sizeof(struct nfnl_net), |
|
}; |
|
|
|
static int __init nfnetlink_init(void) |
|
{ |
|
int i; |
|
|
|
for (i = NFNLGRP_NONE + 1; i <= NFNLGRP_MAX; i++) |
|
BUG_ON(nfnl_group2type[i] == NFNL_SUBSYS_NONE); |
|
|
|
for (i=0; i<NFNL_SUBSYS_COUNT; i++) |
|
__mutex_init(&table[i].mutex, nfnl_lockdep_names[i], &nfnl_lockdep_keys[i]); |
|
|
|
return register_pernet_subsys(&nfnetlink_net_ops); |
|
} |
|
|
|
static void __exit nfnetlink_exit(void) |
|
{ |
|
unregister_pernet_subsys(&nfnetlink_net_ops); |
|
} |
|
module_init(nfnetlink_init); |
|
module_exit(nfnetlink_exit);
|
|
|