From 080774a243f56ce2195ace96fba3d18548ee48ce Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Tue, 9 Aug 2005 19:32:58 -0700 Subject: [NETFILTER]: Add ctnetlink subsystem Add ctnetlink subsystem for userspace-access to ip_conntrack table. This allows reading and updating of existing entries, as well as creating new ones (and new expect's) via nfnetlink. Please note the 'strange' byte order: nfattr (tag+length) are in host byte order, while the payload is always guaranteed to be in network byte order. This allows a simple userspace process to encapsulate netlink messages into arch-independent udp packets by just processing/swapping the headers and not knowing anything about the actual payload. Signed-off-by: Harald Welte Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- include/linux/netfilter/nfnetlink.h | 3 +- include/linux/netfilter/nfnetlink_conntrack.h | 123 +++++++++++++++++++++ include/linux/netfilter_ipv4/ip_conntrack.h | 46 +++++++- include/linux/netfilter_ipv4/ip_conntrack_core.h | 5 + include/linux/netfilter_ipv4/ip_conntrack_helper.h | 2 + .../linux/netfilter_ipv4/ip_conntrack_protocol.h | 24 ++-- include/linux/netfilter_ipv4/ip_nat_protocol.h | 25 +++-- 7 files changed, 210 insertions(+), 18 deletions(-) create mode 100644 include/linux/netfilter/nfnetlink_conntrack.h (limited to 'include/linux') diff --git a/include/linux/netfilter/nfnetlink.h b/include/linux/netfilter/nfnetlink.h index 8f1bfb8d650..ace7a7be074 100644 --- a/include/linux/netfilter/nfnetlink.h +++ b/include/linux/netfilter/nfnetlink.h @@ -56,7 +56,7 @@ struct nfgenmsg { u_int16_t res_id; /* resource id */ } __attribute__ ((packed)); -#define NFNETLINK_V1 1 +#define NFNETLINK_V0 0 #define NFM_NFA(n) ((struct nfattr *)(((char *)(n)) \ + NLMSG_ALIGN(sizeof(struct nfgenmsg)))) @@ -81,6 +81,7 @@ enum nfnl_subsys_id { #ifdef __KERNEL__ +#include #include struct nfnl_callback diff --git a/include/linux/netfilter/nfnetlink_conntrack.h b/include/linux/netfilter/nfnetlink_conntrack.h new file mode 100644 index 00000000000..fb528e0e3bd --- /dev/null +++ b/include/linux/netfilter/nfnetlink_conntrack.h @@ -0,0 +1,123 @@ +#ifndef _IPCONNTRACK_NETLINK_H +#define _IPCONNTRACK_NETLINK_H +#include + +enum cntl_msg_types { + IPCTNL_MSG_CT_NEW, + IPCTNL_MSG_CT_GET, + IPCTNL_MSG_CT_DELETE, + IPCTNL_MSG_CT_GET_CTRZERO, + + IPCTNL_MSG_MAX +}; + +enum ctnl_exp_msg_types { + IPCTNL_MSG_EXP_NEW, + IPCTNL_MSG_EXP_GET, + IPCTNL_MSG_EXP_DELETE, + + IPCTNL_MSG_EXP_MAX +}; + + +enum ctattr_type { + CTA_UNSPEC, + CTA_TUPLE_ORIG, + CTA_TUPLE_REPLY, + CTA_STATUS, + CTA_PROTOINFO, + CTA_HELP, + CTA_NAT, + CTA_TIMEOUT, + CTA_MARK, + CTA_COUNTERS_ORIG, + CTA_COUNTERS_REPLY, + CTA_USE, + CTA_EXPECT, + CTA_ID, + __CTA_MAX +}; +#define CTA_MAX (__CTA_MAX - 1) + +enum ctattr_tuple { + CTA_TUPLE_UNSPEC, + CTA_TUPLE_IP, + CTA_TUPLE_PROTO, + __CTA_TUPLE_MAX +}; +#define CTA_TUPLE_MAX (__CTA_TUPLE_MAX - 1) + +enum ctattr_ip { + CTA_IP_UNSPEC, + CTA_IP_V4_SRC, + CTA_IP_V4_DST, + CTA_IP_V6_SRC, + CTA_IP_V6_DST, + __CTA_IP_MAX +}; +#define CTA_IP_MAX (__CTA_IP_MAX - 1) + +enum ctattr_l4proto { + CTA_PROTO_UNSPEC, + CTA_PROTO_NUM, + CTA_PROTO_SRC_PORT, + CTA_PROTO_DST_PORT, + CTA_PROTO_ICMP_ID, + CTA_PROTO_ICMP_TYPE, + CTA_PROTO_ICMP_CODE, + __CTA_PROTO_MAX +}; +#define CTA_PROTO_MAX (__CTA_PROTO_MAX - 1) + +enum ctattr_protoinfo { + CTA_PROTOINFO_UNSPEC, + CTA_PROTOINFO_TCP_STATE, + __CTA_PROTOINFO_MAX +}; +#define CTA_PROTOINFO_MAX (__CTA_PROTOINFO_MAX - 1) + +enum ctattr_counters { + CTA_COUNTERS_UNSPEC, + CTA_COUNTERS_PACKETS, + CTA_COUNTERS_BYTES, + __CTA_COUNTERS_MAX +}; +#define CTA_COUNTERS_MAX (__CTA_COUNTERS_MAX - 1) + +enum ctattr_nat { + CTA_NAT_UNSPEC, + CTA_NAT_MINIP, + CTA_NAT_MAXIP, + CTA_NAT_PROTO, + __CTA_NAT_MAX +}; +#define CTA_NAT_MAX (__CTA_NAT_MAX - 1) + +enum ctattr_protonat { + CTA_PROTONAT_UNSPEC, + CTA_PROTONAT_PORT_MIN, + CTA_PROTONAT_PORT_MAX, + __CTA_PROTONAT_MAX +}; +#define CTA_PROTONAT_MAX (__CTA_PROTONAT_MAX - 1) + +enum ctattr_expect { + CTA_EXPECT_UNSPEC, + CTA_EXPECT_TUPLE, + CTA_EXPECT_MASK, + CTA_EXPECT_TIMEOUT, + CTA_EXPECT_ID, + __CTA_EXPECT_MAX +}; +#define CTA_EXPECT_MAX (__CTA_EXPECT_MAX - 1) + +enum ctattr_help { + CTA_HELP_UNSPEC, + CTA_HELP_NAME, + __CTA_HELP_MAX +}; +#define CTA_HELP_MAX (__CTA_HELP_MAX - 1) + +#define CTA_HELP_MAXNAMESIZE 32 + +#endif /* _IPCONNTRACK_NETLINK_H */ diff --git a/include/linux/netfilter_ipv4/ip_conntrack.h b/include/linux/netfilter_ipv4/ip_conntrack.h index ae1270c97b5..ff2c1c6001f 100644 --- a/include/linux/netfilter_ipv4/ip_conntrack.h +++ b/include/linux/netfilter_ipv4/ip_conntrack.h @@ -209,6 +209,9 @@ struct ip_conntrack /* Current number of expected connections */ unsigned int expecting; + /* Unique ID that identifies this conntrack*/ + unsigned int id; + /* Helper, if any. */ struct ip_conntrack_helper *helper; @@ -257,6 +260,9 @@ struct ip_conntrack_expect /* Usage count. */ atomic_t use; + /* Unique ID */ + unsigned int id; + #ifdef CONFIG_IP_NF_NAT_NEEDED /* This is the original per-proto part, used to map the * expected connection the way the recipient expects. */ @@ -296,7 +302,12 @@ ip_conntrack_get(const struct sk_buff *skb, enum ip_conntrack_info *ctinfo) } /* decrement reference count on a conntrack */ -extern void ip_conntrack_put(struct ip_conntrack *ct); +static inline void +ip_conntrack_put(struct ip_conntrack *ct) +{ + IP_NF_ASSERT(ct); + nf_conntrack_put(&ct->ct_general); +} /* call to create an explicit dependency on ip_conntrack. */ extern void need_ip_conntrack(void); @@ -331,6 +342,39 @@ extern void ip_ct_iterate_cleanup(int (*iter)(struct ip_conntrack *i, void *data), void *data); +extern struct ip_conntrack_helper * +__ip_conntrack_helper_find_byname(const char *); +extern struct ip_conntrack_helper * +ip_conntrack_helper_find_get(const struct ip_conntrack_tuple *tuple); +extern void ip_conntrack_helper_put(struct ip_conntrack_helper *helper); + +extern struct ip_conntrack_protocol * +__ip_conntrack_proto_find(u_int8_t protocol); +extern struct ip_conntrack_protocol * +ip_conntrack_proto_find_get(u_int8_t protocol); +extern void ip_conntrack_proto_put(struct ip_conntrack_protocol *proto); + +extern void ip_ct_remove_expectations(struct ip_conntrack *ct); + +extern struct ip_conntrack *ip_conntrack_alloc(struct ip_conntrack_tuple *, + struct ip_conntrack_tuple *); + +extern void ip_conntrack_free(struct ip_conntrack *ct); + +extern void ip_conntrack_hash_insert(struct ip_conntrack *ct); + +extern struct ip_conntrack_expect * +__ip_conntrack_expect_find(const struct ip_conntrack_tuple *tuple); + +extern struct ip_conntrack_expect * +ip_conntrack_expect_find_get(const struct ip_conntrack_tuple *tuple); + +extern struct ip_conntrack_tuple_hash * +__ip_conntrack_find(const struct ip_conntrack_tuple *tuple, + const struct ip_conntrack *ignored_conntrack); + +extern void ip_conntrack_flush(void); + /* It's confirmed if it is, or has been in the hash table. */ static inline int is_confirmed(struct ip_conntrack *ct) { diff --git a/include/linux/netfilter_ipv4/ip_conntrack_core.h b/include/linux/netfilter_ipv4/ip_conntrack_core.h index 46eeea1e273..fbf6c3e4164 100644 --- a/include/linux/netfilter_ipv4/ip_conntrack_core.h +++ b/include/linux/netfilter_ipv4/ip_conntrack_core.h @@ -2,6 +2,9 @@ #define _IP_CONNTRACK_CORE_H #include +#define MAX_IP_CT_PROTO 256 +extern struct ip_conntrack_protocol *ip_ct_protos[MAX_IP_CT_PROTO]; + /* This header is used to share core functionality between the standalone connection tracking module, and the compatibility layer's use of connection tracking. */ @@ -53,6 +56,8 @@ struct ip_conntrack_ecache; extern void __ip_ct_deliver_cached_events(struct ip_conntrack_ecache *ec); #endif +extern void __ip_ct_expect_unlink_destroy(struct ip_conntrack_expect *exp); + extern struct list_head *ip_conntrack_hash; extern struct list_head ip_conntrack_expect_list; extern rwlock_t ip_conntrack_lock; diff --git a/include/linux/netfilter_ipv4/ip_conntrack_helper.h b/include/linux/netfilter_ipv4/ip_conntrack_helper.h index 3692daa93de..8d69279ccfe 100644 --- a/include/linux/netfilter_ipv4/ip_conntrack_helper.h +++ b/include/linux/netfilter_ipv4/ip_conntrack_helper.h @@ -24,6 +24,8 @@ struct ip_conntrack_helper int (*help)(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info conntrackinfo); + + int (*to_nfattr)(struct sk_buff *skb, const struct ip_conntrack *ct); }; extern int ip_conntrack_helper_register(struct ip_conntrack_helper *); diff --git a/include/linux/netfilter_ipv4/ip_conntrack_protocol.h b/include/linux/netfilter_ipv4/ip_conntrack_protocol.h index e20b57c5e1b..b6b99be8632 100644 --- a/include/linux/netfilter_ipv4/ip_conntrack_protocol.h +++ b/include/linux/netfilter_ipv4/ip_conntrack_protocol.h @@ -2,6 +2,7 @@ #ifndef _IP_CONNTRACK_PROTOCOL_H #define _IP_CONNTRACK_PROTOCOL_H #include +#include struct seq_file; @@ -47,22 +48,22 @@ struct ip_conntrack_protocol int (*error)(struct sk_buff *skb, enum ip_conntrack_info *ctinfo, unsigned int hooknum); + /* convert protoinfo to nfnetink attributes */ + int (*to_nfattr)(struct sk_buff *skb, struct nfattr *nfa, + const struct ip_conntrack *ct); + + int (*tuple_to_nfattr)(struct sk_buff *skb, + const struct ip_conntrack_tuple *t); + int (*nfattr_to_tuple)(struct nfattr *tb[], + struct ip_conntrack_tuple *t); + /* Module (if any) which this is connected to. */ struct module *me; }; -#define MAX_IP_CT_PROTO 256 -extern struct ip_conntrack_protocol *ip_ct_protos[MAX_IP_CT_PROTO]; - /* Protocol registration. */ extern int ip_conntrack_protocol_register(struct ip_conntrack_protocol *proto); extern void ip_conntrack_protocol_unregister(struct ip_conntrack_protocol *proto); - -static inline struct ip_conntrack_protocol *ip_ct_find_proto(u_int8_t protocol) -{ - return ip_ct_protos[protocol]; -} - /* Existing built-in protocols */ extern struct ip_conntrack_protocol ip_conntrack_protocol_tcp; extern struct ip_conntrack_protocol ip_conntrack_protocol_udp; @@ -73,6 +74,11 @@ extern int ip_conntrack_protocol_tcp_init(void); /* Log invalid packets */ extern unsigned int ip_ct_log_invalid; +extern int ip_ct_port_tuple_to_nfattr(struct sk_buff *, + const struct ip_conntrack_tuple *); +extern int ip_ct_port_nfattr_to_tuple(struct nfattr *tb[], + struct ip_conntrack_tuple *); + #ifdef CONFIG_SYSCTL #ifdef DEBUG_INVALID_PACKETS #define LOG_INVALID(proto) \ diff --git a/include/linux/netfilter_ipv4/ip_nat_protocol.h b/include/linux/netfilter_ipv4/ip_nat_protocol.h index 129708c2238..ef63aa991a0 100644 --- a/include/linux/netfilter_ipv4/ip_nat_protocol.h +++ b/include/linux/netfilter_ipv4/ip_nat_protocol.h @@ -4,6 +4,9 @@ #include #include +#include +#include + struct iphdr; struct ip_nat_range; @@ -15,6 +18,8 @@ struct ip_nat_protocol /* Protocol number. */ unsigned int protonum; + struct module *me; + /* Translate a packet to the target according to manip type. Return true if succeeded. */ int (*manip_pkt)(struct sk_buff **pskb, @@ -43,19 +48,20 @@ struct ip_nat_protocol unsigned int (*print_range)(char *buffer, const struct ip_nat_range *range); -}; -#define MAX_IP_NAT_PROTO 256 -extern struct ip_nat_protocol *ip_nat_protos[MAX_IP_NAT_PROTO]; + int (*range_to_nfattr)(struct sk_buff *skb, + const struct ip_nat_range *range); + + int (*nfattr_to_range)(struct nfattr *tb[], + struct ip_nat_range *range); +}; /* Protocol registration. */ extern int ip_nat_protocol_register(struct ip_nat_protocol *proto); extern void ip_nat_protocol_unregister(struct ip_nat_protocol *proto); -static inline struct ip_nat_protocol *ip_nat_find_proto(u_int8_t protocol) -{ - return ip_nat_protos[protocol]; -} +extern struct ip_nat_protocol *ip_nat_proto_find_get(u_int8_t protocol); +extern void ip_nat_proto_put(struct ip_nat_protocol *proto); /* Built-in protocols. */ extern struct ip_nat_protocol ip_nat_protocol_tcp; @@ -67,4 +73,9 @@ extern int init_protocols(void) __init; extern void cleanup_protocols(void); extern struct ip_nat_protocol *find_nat_proto(u_int16_t protonum); +extern int ip_nat_port_range_to_nfattr(struct sk_buff *skb, + const struct ip_nat_range *range); +extern int ip_nat_port_nfattr_to_range(struct nfattr *tb[], + struct ip_nat_range *range); + #endif /*_IP_NAT_PROTO_H*/ -- cgit v1.2.3