cregit-Linux how code gets into the kernel

Release 4.12 include/net/ip_vs.h

Directory: include/net
/* IP Virtual Server
 * data structure and functionality definitions
 */

#ifndef _NET_IP_VS_H

#define _NET_IP_VS_H

#include <linux/ip_vs.h>                /* definitions shared with userland */

#include <asm/types.h>                  /* for __uXX types */

#include <linux/list.h>                 /* for struct list_head */
#include <linux/spinlock.h>             /* for struct rwlock_t */
#include <linux/atomic.h>               /* for struct atomic_t */
#include <linux/refcount.h>             /* for struct refcount_t */

#include <linux/compiler.h>
#include <linux/timer.h>
#include <linux/bug.h>

#include <net/checksum.h>
#include <linux/netfilter.h>		/* for union nf_inet_addr */
#include <linux/ip.h>
#include <linux/ipv6.h>			/* for struct ipv6hdr */
#include <net/ipv6.h>
#if IS_ENABLED(CONFIG_IP_VS_IPV6)
#include <linux/netfilter_ipv6/ip6_tables.h>
#endif
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
#include <net/netfilter/nf_conntrack.h>
#endif
#include <net/net_namespace.h>		/* Netw namespace */


#define IP_VS_HDR_INVERSE	1

#define IP_VS_HDR_ICMP		2

/* Generic access of ipvs struct */

static inline struct netns_ipvs *net_ipvs(struct net* net) { return net->ipvs; }

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/* This one needed for single_open_net since net is stored directly in * private not as a struct i.e. seq_file_net can't be used. */
static inline struct net *seq_file_single_net(struct seq_file *seq) { #ifdef CONFIG_NET_NS return (struct net *)seq->private; #else return &init_net; #endif }

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/* Connections' size value needed by ip_vs_ctl.c */ extern int ip_vs_conn_tab_size; struct ip_vs_iphdr { int hdr_flags; /* ipvs flags */ __u32 off; /* Where IP or IPv4 header starts */ __u32 len; /* IPv4 simply where L4 starts * IPv6 where L4 Transport Header starts */ __u16 fragoffs; /* IPv6 fragment offset, 0 if first frag (or not frag)*/ __s16 protocol; __s32 flags; union nf_inet_addr saddr; union nf_inet_addr daddr; };
static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset, int len, void *buffer, const struct ip_vs_iphdr *ipvsh) { return skb_header_pointer(skb, offset, len, buffer); }

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/* This function handles filling *ip_vs_iphdr, both for IPv4 and IPv6. * IPv6 requires some extra work, as finding proper header position, * depend on the IPv6 extension headers. */
static inline int ip_vs_fill_iph_skb_off(int af, const struct sk_buff *skb, int offset, int hdr_flags, struct ip_vs_iphdr *iphdr) { iphdr->hdr_flags = hdr_flags; iphdr->off = offset; #ifdef CONFIG_IP_VS_IPV6 if (af == AF_INET6) { struct ipv6hdr _iph; const struct ipv6hdr *iph = skb_header_pointer( skb, offset, sizeof(_iph), &_iph); if (!iph) return 0; iphdr->saddr.in6 = iph->saddr; iphdr->daddr.in6 = iph->daddr; /* ipv6_find_hdr() updates len, flags */ iphdr->len = offset; iphdr->flags = 0; iphdr->protocol = ipv6_find_hdr(skb, &iphdr->len, -1, &iphdr->fragoffs, &iphdr->flags); if (iphdr->protocol < 0) return 0; } else #endif { struct iphdr _iph; const struct iphdr *iph = skb_header_pointer( skb, offset, sizeof(_iph), &_iph); if (!iph) return 0; iphdr->len = offset + iph->ihl * 4; iphdr->fragoffs = 0; iphdr->protocol = iph->protocol; iphdr->saddr.ip = iph->saddr; iphdr->daddr.ip = iph->daddr; } return 1; }

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Jiri Pirko10.41%116.67%
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static inline int ip_vs_fill_iph_skb_icmp(int af, const struct sk_buff *skb, int offset, bool inverse, struct ip_vs_iphdr *iphdr) { int hdr_flags = IP_VS_HDR_ICMP; if (inverse) hdr_flags |= IP_VS_HDR_INVERSE; return ip_vs_fill_iph_skb_off(af, skb, offset, hdr_flags, iphdr); }

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static inline int ip_vs_fill_iph_skb(int af, const struct sk_buff *skb, bool inverse, struct ip_vs_iphdr *iphdr) { int hdr_flags = 0; if (inverse) hdr_flags |= IP_VS_HDR_INVERSE; return ip_vs_fill_iph_skb_off(af, skb, skb_network_offset(skb), hdr_flags, iphdr); }

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Jesper Dangaard Brouer11.85%133.33%
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static inline bool ip_vs_iph_inverse(const struct ip_vs_iphdr *iph) { return !!(iph->hdr_flags & IP_VS_HDR_INVERSE); }

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static inline bool ip_vs_iph_icmp(const struct ip_vs_iphdr *iph) { return !!(iph->hdr_flags & IP_VS_HDR_ICMP); }

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static inline void ip_vs_addr_copy(int af, union nf_inet_addr *dst, const union nf_inet_addr *src) { #ifdef CONFIG_IP_VS_IPV6 if (af == AF_INET6) dst->in6 = src->in6; else #endif dst->ip = src->ip; }

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static inline void ip_vs_addr_set(int af, union nf_inet_addr *dst, const union nf_inet_addr *src) { #ifdef CONFIG_IP_VS_IPV6 if (af == AF_INET6) { dst->in6 = src->in6; return; } #endif dst->ip = src->ip; dst->all[1] = 0; dst->all[2] = 0; dst->all[3] = 0; }

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static inline int ip_vs_addr_equal(int af, const union nf_inet_addr *a, const union nf_inet_addr *b) { #ifdef CONFIG_IP_VS_IPV6 if (af == AF_INET6) return ipv6_addr_equal(&a->in6, &b->in6); #endif return a->ip == b->ip; }

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#ifdef CONFIG_IP_VS_DEBUG #include <linux/net.h> int ip_vs_get_debug_level(void);
static inline const char *ip_vs_dbg_addr(int af, char *buf, size_t buf_len, const union nf_inet_addr *addr, int *idx) { int len; #ifdef CONFIG_IP_VS_IPV6 if (af == AF_INET6) len = snprintf(&buf[*idx], buf_len - *idx, "[%pI6c]", &addr->in6) + 1; else #endif len = snprintf(&buf[*idx], buf_len - *idx, "%pI4", &addr->ip) + 1; *idx += len; BUG_ON(*idx > buf_len + 1); return &buf[*idx - len]; }

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#define IP_VS_DBG_BUF(level, msg, ...) \ do { \ char ip_vs_dbg_buf[160]; \ int ip_vs_dbg_idx = 0; \ if (level <= ip_vs_get_debug_level()) \ printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__); \ } while (0) #define IP_VS_ERR_BUF(msg...) \ do { \ char ip_vs_dbg_buf[160]; \ int ip_vs_dbg_idx = 0; \ pr_err(msg); \ } while (0) /* Only use from within IP_VS_DBG_BUF() or IP_VS_ERR_BUF macros */ #define IP_VS_DBG_ADDR(af, addr) \ ip_vs_dbg_addr(af, ip_vs_dbg_buf, \ sizeof(ip_vs_dbg_buf), addr, \ &ip_vs_dbg_idx) #define IP_VS_DBG(level, msg, ...) \ do { \ if (level <= ip_vs_get_debug_level()) \ printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__); \ } while (0) #define IP_VS_DBG_RL(msg, ...) \ do { \ if (net_ratelimit()) \ printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__); \ } while (0) #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg) \ do { \ if (level <= ip_vs_get_debug_level()) \ pp->debug_packet(af, pp, skb, ofs, msg); \ } while (0) #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg) \ do { \ if (level <= ip_vs_get_debug_level() && \ net_ratelimit()) \ pp->debug_packet(af, pp, skb, ofs, msg); \ } while (0) #else /* NO DEBUGGING at ALL */ #define IP_VS_DBG_BUF(level, msg...) do {} while (0) #define IP_VS_ERR_BUF(msg...) do {} while (0) #define IP_VS_DBG(level, msg...) do {} while (0) #define IP_VS_DBG_RL(msg...) do {} while (0) #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg) do {} while (0) #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg) do {} while (0) #endif #define IP_VS_BUG() BUG() #define IP_VS_ERR_RL(msg, ...) \ do { \ if (net_ratelimit()) \ pr_err(msg, ##__VA_ARGS__); \ } while (0) #ifdef CONFIG_IP_VS_DEBUG #define EnterFunction(level) \ do { \ if (level <= ip_vs_get_debug_level()) \ printk(KERN_DEBUG \ pr_fmt("Enter: %s, %s line %i\n"), \ __func__, __FILE__, __LINE__); \ } while (0) #define LeaveFunction(level) \ do { \ if (level <= ip_vs_get_debug_level()) \ printk(KERN_DEBUG \ pr_fmt("Leave: %s, %s line %i\n"), \ __func__, __FILE__, __LINE__); \ } while (0) #else #define EnterFunction(level) do {} while (0) #define LeaveFunction(level) do {} while (0) #endif /* The port number of FTP service (in network order). */ #define FTPPORT cpu_to_be16(21) #define FTPDATA cpu_to_be16(20) /* TCP State Values */ enum { IP_VS_TCP_S_NONE = 0, IP_VS_TCP_S_ESTABLISHED, IP_VS_TCP_S_SYN_SENT, IP_VS_TCP_S_SYN_RECV, IP_VS_TCP_S_FIN_WAIT, IP_VS_TCP_S_TIME_WAIT, IP_VS_TCP_S_CLOSE, IP_VS_TCP_S_CLOSE_WAIT, IP_VS_TCP_S_LAST_ACK, IP_VS_TCP_S_LISTEN, IP_VS_TCP_S_SYNACK, IP_VS_TCP_S_LAST }; /* UDP State Values */ enum { IP_VS_UDP_S_NORMAL, IP_VS_UDP_S_LAST, }; /* ICMP State Values */ enum { IP_VS_ICMP_S_NORMAL, IP_VS_ICMP_S_LAST, }; /* SCTP State Values */ enum ip_vs_sctp_states { IP_VS_SCTP_S_NONE, IP_VS_SCTP_S_INIT1, IP_VS_SCTP_S_INIT, IP_VS_SCTP_S_COOKIE_SENT, IP_VS_SCTP_S_COOKIE_REPLIED, IP_VS_SCTP_S_COOKIE_WAIT, IP_VS_SCTP_S_COOKIE, IP_VS_SCTP_S_COOKIE_ECHOED, IP_VS_SCTP_S_ESTABLISHED, IP_VS_SCTP_S_SHUTDOWN_SENT, IP_VS_SCTP_S_SHUTDOWN_RECEIVED, IP_VS_SCTP_S_SHUTDOWN_ACK_SENT, IP_VS_SCTP_S_REJECTED, IP_VS_SCTP_S_CLOSED, IP_VS_SCTP_S_LAST }; /* Delta sequence info structure * Each ip_vs_conn has 2 (output AND input seq. changes). * Only used in the VS/NAT. */ struct ip_vs_seq { __u32 init_seq; /* Add delta from this seq */ __u32 delta; /* Delta in sequence numbers */ __u32 previous_delta; /* Delta in sequence numbers * before last resized pkt */ }; /* counters per cpu */ struct ip_vs_counters { __u64 conns; /* connections scheduled */ __u64 inpkts; /* incoming packets */ __u64 outpkts; /* outgoing packets */ __u64 inbytes; /* incoming bytes */ __u64 outbytes; /* outgoing bytes */ }; /* Stats per cpu */ struct ip_vs_cpu_stats { struct ip_vs_counters cnt; struct u64_stats_sync syncp; }; /* IPVS statistics objects */ struct ip_vs_estimator { struct list_head list; u64 last_inbytes; u64 last_outbytes; u64 last_conns; u64 last_inpkts; u64 last_outpkts; u64 cps; u64 inpps; u64 outpps; u64 inbps; u64 outbps; }; /* * IPVS statistics object, 64-bit kernel version of struct ip_vs_stats_user */ struct ip_vs_kstats { u64 conns; /* connections scheduled */ u64 inpkts; /* incoming packets */ u64 outpkts; /* outgoing packets */ u64 inbytes; /* incoming bytes */ u64 outbytes; /* outgoing bytes */ u64 cps; /* current connection rate */ u64 inpps; /* current in packet rate */ u64 outpps; /* current out packet rate */ u64 inbps; /* current in byte rate */ u64 outbps; /* current out byte rate */ }; struct ip_vs_stats { struct ip_vs_kstats kstats; /* kernel statistics */ struct ip_vs_estimator est; /* estimator */ struct ip_vs_cpu_stats __percpu *cpustats; /* per cpu counters */ spinlock_t lock; /* spin lock */ struct ip_vs_kstats kstats0; /* reset values */ }; struct dst_entry; struct iphdr; struct ip_vs_conn; struct ip_vs_app; struct sk_buff; struct ip_vs_proto_data; struct ip_vs_protocol { struct ip_vs_protocol *next; char *name; u16 protocol; u16 num_states; int dont_defrag; void (*init)(struct ip_vs_protocol *pp); void (*exit)(struct ip_vs_protocol *pp); int (*init_netns)(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd); void (*exit_netns)(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd); int (*conn_schedule)(struct netns_ipvs *ipvs, int af, struct sk_buff *skb, struct ip_vs_proto_data *pd, int *verdict, struct ip_vs_conn **cpp, struct ip_vs_iphdr *iph); struct ip_vs_conn * (*conn_in_get)(struct netns_ipvs *ipvs, int af, const struct sk_buff *skb, const struct ip_vs_iphdr *iph); struct ip_vs_conn * (*conn_out_get)(struct netns_ipvs *ipvs, int af, const struct sk_buff *skb, const struct ip_vs_iphdr *iph); int (*snat_handler)(struct sk_buff *skb, struct ip_vs_protocol *pp, struct ip_vs_conn *cp, struct ip_vs_iphdr *iph); int (*dnat_handler)(struct sk_buff *skb, struct ip_vs_protocol *pp, struct ip_vs_conn *cp, struct ip_vs_iphdr *iph); int (*csum_check)(int af, struct sk_buff *skb, struct ip_vs_protocol *pp); const char *(*state_name)(int state); void (*state_transition)(struct ip_vs_conn *cp, int direction, const struct sk_buff *skb, struct ip_vs_proto_data *pd); int (*register_app)(struct netns_ipvs *ipvs, struct ip_vs_app *inc); void (*unregister_app)(struct netns_ipvs *ipvs, struct ip_vs_app *inc); int (*app_conn_bind)(struct ip_vs_conn *cp); void (*debug_packet)(int af, struct ip_vs_protocol *pp, const struct sk_buff *skb, int offset, const char *msg); void (*timeout_change)(struct ip_vs_proto_data *pd, int flags); }; /* protocol data per netns */ struct ip_vs_proto_data { struct ip_vs_proto_data *next; struct ip_vs_protocol *pp; int *timeout_table; /* protocol timeout table */ atomic_t appcnt; /* counter of proto app incs. */ struct tcp_states_t *tcp_state_table; }; struct ip_vs_protocol *ip_vs_proto_get(unsigned short proto); struct ip_vs_proto_data *ip_vs_proto_data_get(struct netns_ipvs *ipvs, unsigned short proto); struct ip_vs_conn_param { struct netns_ipvs *ipvs; const union nf_inet_addr *caddr; const union nf_inet_addr *vaddr; __be16 cport; __be16 vport; __u16 protocol; u16 af; const struct ip_vs_pe *pe; char *pe_data; __u8 pe_data_len; }; /* IP_VS structure allocated for each dynamically scheduled connection */ struct ip_vs_conn { struct hlist_node c_list; /* hashed list heads */ /* Protocol, addresses and port numbers */ __be16 cport; __be16 dport; __be16 vport; u16 af; /* address family */ union nf_inet_addr caddr; /* client address */ union nf_inet_addr vaddr; /* virtual address */ union nf_inet_addr daddr; /* destination address */ volatile __u32 flags; /* status flags */ __u16 protocol; /* Which protocol (TCP/UDP) */ __u16 daf; /* Address family of the dest */ struct netns_ipvs *ipvs; /* counter and timer */ refcount_t refcnt; /* reference count */ struct timer_list timer; /* Expiration timer */ volatile unsigned long timeout; /* timeout */ /* Flags and state transition */ spinlock_t lock; /* lock for state transition */ volatile __u16 state; /* state info */ volatile __u16 old_state; /* old state, to be used for * state transition triggerd * synchronization */ __u32 fwmark; /* Fire wall mark from skb */ unsigned long sync_endtime; /* jiffies + sent_retries */ /* Control members */ struct ip_vs_conn *control; /* Master control connection */ atomic_t n_control; /* Number of controlled ones */ struct ip_vs_dest *dest; /* real server */ atomic_t in_pkts; /* incoming packet counter */ /* Packet transmitter for different forwarding methods. If it * mangles the packet, it must return NF_DROP or better NF_STOLEN, * otherwise this must be changed to a sk_buff **. * NF_ACCEPT can be returned when destination is local. */ int (*packet_xmit)(struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph); /* Note: we can group the following members into a structure, * in order to save more space, and the following members are * only used in VS/NAT anyway */ struct ip_vs_app *app; /* bound ip_vs_app object */ void *app_data; /* Application private data */ struct ip_vs_seq in_seq; /* incoming seq. struct */ struct ip_vs_seq out_seq; /* outgoing seq. struct */ const struct ip_vs_pe *pe; char *pe_data; __u8 pe_data_len; struct rcu_head rcu_head; }; /* Extended internal versions of struct ip_vs_service_user and ip_vs_dest_user * for IPv6 support. * * We need these to conveniently pass around service and destination * options, but unfortunately, we also need to keep the old definitions to * maintain userspace backwards compatibility for the setsockopt interface. */ struct ip_vs_service_user_kern { /* virtual service addresses */ u16 af; u16 protocol; union nf_inet_addr addr; /* virtual ip address */ __be16 port; u32 fwmark; /* firwall mark of service */ /* virtual service options */ char *sched_name; char *pe_name; unsigned int flags; /* virtual service flags */ unsigned int timeout; /* persistent timeout in sec */ __be32 netmask; /* persistent netmask or plen */ }; struct ip_vs_dest_user_kern { /* destination server address */ union nf_inet_addr addr; __be16 port; /* real server options */ unsigned int conn_flags; /* connection flags */ int weight; /* destination weight */ /* thresholds for active connections */ u32 u_threshold; /* upper threshold */ u32 l_threshold; /* lower threshold */ /* Address family of addr */ u16 af; }; /* * The information about the virtual service offered to the net and the * forwarding entries. */ struct ip_vs_service { struct hlist_node s_list; /* for normal service table */ struct hlist_node f_list; /* for fwmark-based service table */ atomic_t refcnt; /* reference counter */ u16 af; /* address family */ __u16 protocol; /* which protocol (TCP/UDP) */ union nf_inet_addr addr; /* IP address for virtual service */ __be16 port; /* port number for the service */ __u32 fwmark; /* firewall mark of the service */ unsigned int flags; /* service status flags */ unsigned int timeout; /* persistent timeout in ticks */ __be32 netmask; /* grouping granularity, mask/plen */ struct netns_ipvs *ipvs; struct list_head destinations; /* real server d-linked list */ __u32 num_dests; /* number of servers */ struct ip_vs_stats stats; /* statistics for the service */ /* for scheduling */ struct ip_vs_scheduler __rcu *scheduler; /* bound scheduler object */ spinlock_t sched_lock; /* lock sched_data */ void *sched_data; /* scheduler application data */ /* alternate persistence engine */ struct ip_vs_pe __rcu *pe; struct rcu_head rcu_head; }; /* Information for cached dst */ struct ip_vs_dest_dst { struct dst_entry *dst_cache; /* destination cache entry */ u32 dst_cookie; union nf_inet_addr dst_saddr; struct rcu_head rcu_head; }; /* The real server destination forwarding entry with ip address, port number, * and so on. */ struct ip_vs_dest { struct list_head n_list; /* for the dests in the service */ struct hlist_node d_list; /* for table with all the dests */ u16 af; /* address family */ __be16 port; /* port number of the server */ union nf_inet_addr addr; /* IP address of the server */ volatile unsigned int flags; /* dest status flags */ atomic_t conn_flags; /* flags to copy to conn */ atomic_t weight; /* server weight */ refcount_t refcnt; /* reference counter */ struct ip_vs_stats stats; /* statistics */ unsigned long idle_start; /* start time, jiffies */ /* connection counters and thresholds */ atomic_t activeconns; /* active connections */ atomic_t inactconns; /* inactive connections */ atomic_t persistconns; /* persistent connections */ __u32 u_threshold; /* upper threshold */ __u32 l_threshold; /* lower threshold */ /* for destination cache */ spinlock_t dst_lock; /* lock of dst_cache */ struct ip_vs_dest_dst __rcu *dest_dst; /* cached dst info */ /* for virtual service */ struct ip_vs_service __rcu *svc; /* service it belongs to */ __u16 protocol; /* which protocol (TCP/UDP) */ __be16 vport; /* virtual port number */ union nf_inet_addr vaddr; /* virtual IP address */ __u32 vfwmark; /* firewall mark of service */ struct list_head t_list; /* in dest_trash */ unsigned int in_rs_table:1; /* we are in rs_table */ }; /* The scheduler object */ struct ip_vs_scheduler { struct list_head n_list; /* d-linked list head */ char *name; /* scheduler name */ atomic_t refcnt; /* reference counter */ struct module *module; /* THIS_MODULE/NULL */ /* scheduler initializing service */ int (*init_service)(struct ip_vs_service *svc); /* scheduling service finish */ void (*done_service)(struct ip_vs_service *svc); /* dest is linked */ int (*add_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest); /* dest is unlinked */ int (*del_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest); /* dest is updated */ int (*upd_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest); /* selecting a server from the given service */ struct ip_vs_dest* (*schedule)(struct ip_vs_service *svc, const struct sk_buff *skb, struct ip_vs_iphdr *iph); }; /* The persistence engine object */ struct ip_vs_pe { struct list_head n_list; /* d-linked list head */ char *name; /* scheduler name */ atomic_t refcnt; /* reference counter */ struct module *module; /* THIS_MODULE/NULL */ /* get the connection template, if any */ int (*fill_param)(struct ip_vs_conn_param *p, struct sk_buff *skb); bool (*ct_match)(const struct ip_vs_conn_param *p, struct ip_vs_conn *ct); u32 (*hashkey_raw)(const struct ip_vs_conn_param *p, u32 initval, bool inverse); int (*show_pe_data)(const struct ip_vs_conn *cp, char *buf); /* create connections for real-server outgoing packets */