From ceceae1b1555a9afcb8dacf90df5fa1f20fd5466 Mon Sep 17 00:00:00 2001 From: Yasuyuki Kozakai Date: Sat, 7 Jul 2007 22:23:42 -0700 Subject: [PATCH] [NETFILTER]: nf_conntrack: use extension infrastructure for helper Signed-off-by: Yasuyuki Kozakai Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- include/net/netfilter/nf_conntrack.h | 26 ------- include/net/netfilter/nf_conntrack_core.h | 3 + include/net/netfilter/nf_conntrack_extend.h | 3 + include/net/netfilter/nf_conntrack_helper.h | 5 ++ net/ipv4/netfilter/nf_nat_standalone.c | 10 --- net/netfilter/nf_conntrack_core.c | 80 +++++++++++++-------- net/netfilter/nf_conntrack_helper.c | 27 ++++--- net/netfilter/nf_conntrack_netlink.c | 37 +++++----- 8 files changed, 99 insertions(+), 92 deletions(-) diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h index c31382d3ef1..f1e0fee9aa9 100644 --- a/include/net/netfilter/nf_conntrack.h +++ b/include/net/netfilter/nf_conntrack.h @@ -294,32 +294,6 @@ static inline struct nf_conn_nat *nfct_nat(const struct nf_conn *ct) offset = ALIGN(offset, __alignof__(struct nf_conn_nat)); return (struct nf_conn_nat *) ((void *)ct + offset); } - -static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct) -{ - unsigned int offset = sizeof(struct nf_conn); - - if (!(ct->features & NF_CT_F_HELP)) - return NULL; - if (ct->features & NF_CT_F_NAT) { - offset = ALIGN(offset, __alignof__(struct nf_conn_nat)); - offset += sizeof(struct nf_conn_nat); - } - - offset = ALIGN(offset, __alignof__(struct nf_conn_help)); - return (struct nf_conn_help *) ((void *)ct + offset); -} -#else /* No NAT */ -static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct) -{ - unsigned int offset = sizeof(struct nf_conn); - - if (!(ct->features & NF_CT_F_HELP)) - return NULL; - - offset = ALIGN(offset, __alignof__(struct nf_conn_help)); - return (struct nf_conn_help *) ((void *)ct + offset); -} #endif /* CONFIG_NF_NAT_NEEDED */ #endif /* __KERNEL__ */ #endif /* _NF_CONNTRACK_H */ diff --git a/include/net/netfilter/nf_conntrack_core.h b/include/net/netfilter/nf_conntrack_core.h index 9fb906688ff..3bf7d05ea64 100644 --- a/include/net/netfilter/nf_conntrack_core.h +++ b/include/net/netfilter/nf_conntrack_core.h @@ -30,6 +30,9 @@ extern void nf_conntrack_cleanup(void); extern int nf_conntrack_proto_init(void); extern void nf_conntrack_proto_fini(void); +extern int nf_conntrack_helper_init(void); +extern void nf_conntrack_helper_fini(void); + struct nf_conntrack_l3proto; extern struct nf_conntrack_l3proto *nf_ct_find_l3proto(u_int16_t pf); /* Like above, but you already have conntrack read lock. */ diff --git a/include/net/netfilter/nf_conntrack_extend.h b/include/net/netfilter/nf_conntrack_extend.h index 8a988d13646..05357dc5d2d 100644 --- a/include/net/netfilter/nf_conntrack_extend.h +++ b/include/net/netfilter/nf_conntrack_extend.h @@ -5,9 +5,12 @@ enum nf_ct_ext_id { + NF_CT_EXT_HELPER, NF_CT_EXT_NUM, }; +#define NF_CT_EXT_HELPER_TYPE struct nf_conn_help + /* Extensions: optional stuff which isn't permanently in struct. */ struct nf_ct_ext { u8 offset[NF_CT_EXT_NUM]; diff --git a/include/net/netfilter/nf_conntrack_helper.h b/include/net/netfilter/nf_conntrack_helper.h index 8c72ac9f0ab..b43a75ba44a 100644 --- a/include/net/netfilter/nf_conntrack_helper.h +++ b/include/net/netfilter/nf_conntrack_helper.h @@ -10,6 +10,7 @@ #ifndef _NF_CONNTRACK_HELPER_H #define _NF_CONNTRACK_HELPER_H #include +#include struct module; @@ -52,4 +53,8 @@ extern void nf_ct_helper_put(struct nf_conntrack_helper *helper); extern int nf_conntrack_helper_register(struct nf_conntrack_helper *); extern void nf_conntrack_helper_unregister(struct nf_conntrack_helper *); +static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct) +{ + return nf_ct_ext_find(ct, NF_CT_EXT_HELPER); +} #endif /*_NF_CONNTRACK_HELPER_H*/ diff --git a/net/ipv4/netfilter/nf_nat_standalone.c b/net/ipv4/netfilter/nf_nat_standalone.c index 55dac36dbc8..0b2f0c33f7c 100644 --- a/net/ipv4/netfilter/nf_nat_standalone.c +++ b/net/ipv4/netfilter/nf_nat_standalone.c @@ -338,14 +338,6 @@ static int __init nf_nat_standalone_init(void) return ret; } - size = ALIGN(size, __alignof__(struct nf_conn_help)) + - sizeof(struct nf_conn_help); - ret = nf_conntrack_register_cache(NF_CT_F_NAT|NF_CT_F_HELP, - "nf_nat:help", size); - if (ret < 0) { - printk(KERN_ERR "nf_nat_init: Unable to create slab cache\n"); - goto cleanup_register_cache; - } #ifdef CONFIG_XFRM BUG_ON(ip_nat_decode_session != NULL); ip_nat_decode_session = nat_decode_session; @@ -370,8 +362,6 @@ static int __init nf_nat_standalone_init(void) ip_nat_decode_session = NULL; synchronize_net(); #endif - nf_conntrack_unregister_cache(NF_CT_F_NAT|NF_CT_F_HELP); - cleanup_register_cache: nf_conntrack_unregister_cache(NF_CT_F_NAT); return ret; } diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index b56f954895b..914506e6c78 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -566,7 +566,6 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig, u_int32_t features) { struct nf_conn *conntrack = NULL; - struct nf_conntrack_helper *helper; if (unlikely(!nf_conntrack_hash_rnd_initted)) { get_random_bytes(&nf_conntrack_hash_rnd, 4); @@ -593,14 +592,6 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig, /* find features needed by this conntrack. */ features |= l3proto->get_features(orig); - /* FIXME: protect helper list per RCU */ - read_lock_bh(&nf_conntrack_lock); - helper = __nf_ct_helper_find(repl); - /* NAT might want to assign a helper later */ - if (helper || features & NF_CT_F_NAT) - features |= NF_CT_F_HELP; - read_unlock_bh(&nf_conntrack_lock); - DEBUGP("nf_conntrack_alloc: features=0x%x\n", features); read_lock_bh(&nf_ct_cache_lock); @@ -681,12 +672,6 @@ init_conntrack(const struct nf_conntrack_tuple *tuple, return NULL; } - read_lock_bh(&nf_conntrack_lock); - exp = __nf_conntrack_expect_find(tuple); - if (exp && exp->helper) - features = NF_CT_F_HELP; - read_unlock_bh(&nf_conntrack_lock); - conntrack = __nf_conntrack_alloc(tuple, &repl_tuple, l3proto, features); if (conntrack == NULL || IS_ERR(conntrack)) { DEBUGP("Can't allocate conntrack.\n"); @@ -701,16 +686,21 @@ init_conntrack(const struct nf_conntrack_tuple *tuple, write_lock_bh(&nf_conntrack_lock); exp = find_expectation(tuple); - - help = nfct_help(conntrack); if (exp) { DEBUGP("conntrack: expectation arrives ct=%p exp=%p\n", conntrack, exp); /* Welcome, Mr. Bond. We've been expecting you... */ __set_bit(IPS_EXPECTED_BIT, &conntrack->status); conntrack->master = exp->master; - if (exp->helper) - rcu_assign_pointer(help->helper, exp->helper); + if (exp->helper) { + help = nf_ct_ext_add(conntrack, NF_CT_EXT_HELPER, + GFP_ATOMIC); + if (help) + rcu_assign_pointer(help->helper, exp->helper); + else + DEBUGP("failed to add helper extension area"); + } + #ifdef CONFIG_NF_CONNTRACK_MARK conntrack->mark = exp->master->mark; #endif @@ -720,10 +710,18 @@ init_conntrack(const struct nf_conntrack_tuple *tuple, nf_conntrack_get(&conntrack->master->ct_general); NF_CT_STAT_INC(expect_new); } else { - if (help) { - /* not in hash table yet, so not strictly necessary */ - rcu_assign_pointer(help->helper, - __nf_ct_helper_find(&repl_tuple)); + struct nf_conntrack_helper *helper; + + helper = __nf_ct_helper_find(&repl_tuple); + if (helper) { + help = nf_ct_ext_add(conntrack, NF_CT_EXT_HELPER, + GFP_ATOMIC); + if (help) + /* not in hash table yet, so not strictly + necessary */ + rcu_assign_pointer(help->helper, helper); + else + DEBUGP("failed to add helper extension area"); } NF_CT_STAT_INC(new); } @@ -892,6 +890,7 @@ void nf_conntrack_alter_reply(struct nf_conn *ct, const struct nf_conntrack_tuple *newreply) { struct nf_conn_help *help = nfct_help(ct); + struct nf_conntrack_helper *helper; write_lock_bh(&nf_conntrack_lock); /* Should be unconfirmed, so not in hash table yet */ @@ -901,14 +900,28 @@ void nf_conntrack_alter_reply(struct nf_conn *ct, NF_CT_DUMP_TUPLE(newreply); ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply; - if (!ct->master && help && help->expecting == 0) { - struct nf_conntrack_helper *helper; - helper = __nf_ct_helper_find(newreply); - if (helper) - memset(&help->help, 0, sizeof(help->help)); - /* not in hash table yet, so not strictly necessary */ - rcu_assign_pointer(help->helper, helper); + if (ct->master || (help && help->expecting != 0)) + goto out; + + helper = __nf_ct_helper_find(newreply); + if (helper == NULL) { + if (help) + rcu_assign_pointer(help->helper, NULL); + goto out; } + + if (help == NULL) { + help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, GFP_ATOMIC); + if (help == NULL) { + DEBUGP("failed to add helper extension area"); + goto out; + } + } else { + memset(&help->help, 0, sizeof(help->help)); + } + + rcu_assign_pointer(help->helper, helper); +out: write_unlock_bh(&nf_conntrack_lock); } EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply); @@ -1150,6 +1163,7 @@ void nf_conntrack_cleanup(void) nf_conntrack_htable_size); nf_conntrack_proto_fini(); + nf_conntrack_helper_fini(); } static struct list_head *alloc_hashtable(int size, int *vmalloced) @@ -1272,6 +1286,10 @@ int __init nf_conntrack_init(void) if (ret < 0) goto out_free_expect_slab; + ret = nf_conntrack_helper_init(); + if (ret < 0) + goto out_fini_proto; + /* For use by REJECT target */ rcu_assign_pointer(ip_ct_attach, __nf_conntrack_attach); rcu_assign_pointer(nf_ct_destroy, destroy_conntrack); @@ -1284,6 +1302,8 @@ int __init nf_conntrack_init(void) return ret; +out_fini_proto: + nf_conntrack_proto_fini(); out_free_expect_slab: kmem_cache_destroy(nf_conntrack_expect_cachep); err_free_conntrack_slab: diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c index f868b7fbd9b..6d32399d64e 100644 --- a/net/netfilter/nf_conntrack_helper.c +++ b/net/netfilter/nf_conntrack_helper.c @@ -26,6 +26,7 @@ #include #include #include +#include static __read_mostly LIST_HEAD(helpers); @@ -100,18 +101,8 @@ static inline int unhelp(struct nf_conntrack_tuple_hash *i, int nf_conntrack_helper_register(struct nf_conntrack_helper *me) { - int size, ret; - BUG_ON(me->timeout == 0); - size = ALIGN(sizeof(struct nf_conn), __alignof__(struct nf_conn_help)) + - sizeof(struct nf_conn_help); - ret = nf_conntrack_register_cache(NF_CT_F_HELP, "nf_conntrack:help", - size); - if (ret < 0) { - printk(KERN_ERR "nf_conntrack_helper_register: Unable to create slab cache for conntracks\n"); - return ret; - } write_lock_bh(&nf_conntrack_lock); list_add(&me->list, &helpers); write_unlock_bh(&nf_conntrack_lock); @@ -153,3 +144,19 @@ void nf_conntrack_helper_unregister(struct nf_conntrack_helper *me) synchronize_net(); } EXPORT_SYMBOL_GPL(nf_conntrack_helper_unregister); + +struct nf_ct_ext_type helper_extend = { + .len = sizeof(struct nf_conn_help), + .align = __alignof__(struct nf_conn_help), + .id = NF_CT_EXT_HELPER, +}; + +int nf_conntrack_helper_init() +{ + return nf_ct_extend_register(&helper_extend); +} + +void nf_conntrack_helper_fini() +{ + nf_ct_extend_unregister(&helper_extend); +} diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index d0fe3d76982..3d56f36074f 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -856,23 +856,23 @@ ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[]) return 0; } - if (!help) { - /* FIXME: we need to reallocate and rehash */ - return -EBUSY; - } - helper = __nf_conntrack_helper_find_byname(helpname); if (helper == NULL) return -EINVAL; - if (help->helper == helper) - return 0; - - if (help->helper) - return -EBUSY; + if (help) { + if (help->helper == helper) + return 0; + if (help->helper) + return -EBUSY; + /* need to zero data of old helper */ + memset(&help->help, 0, sizeof(help->help)); + } else { + help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, GFP_KERNEL); + if (help == NULL) + return -ENOMEM; + } - /* need to zero data of old helper */ - memset(&help->help, 0, sizeof(help->help)); rcu_assign_pointer(help->helper, helper); return 0; @@ -957,7 +957,7 @@ ctnetlink_create_conntrack(struct nfattr *cda[], struct nf_conn *ct; int err = -EINVAL; struct nf_conn_help *help; - struct nf_conntrack_helper *helper = NULL; + struct nf_conntrack_helper *helper; ct = nf_conntrack_alloc(otuple, rtuple); if (ct == NULL || IS_ERR(ct)) @@ -987,9 +987,14 @@ ctnetlink_create_conntrack(struct nfattr *cda[], ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1])); #endif - help = nfct_help(ct); - if (help) { - helper = nf_ct_helper_find_get(rtuple); + helper = nf_ct_helper_find_get(rtuple); + if (helper) { + help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, GFP_KERNEL); + if (help == NULL) { + nf_ct_helper_put(helper); + err = -ENOMEM; + goto err; + } /* not in hash table yet so not strictly necessary */ rcu_assign_pointer(help->helper, helper); } -- 2.41.1