2 * Copyright (c) 2005 Paolo Pisati <piso@FreeBSD.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * $FreeBSD: src/sys/netinet/libalias/alias_mod.h,v 1.1.6.1 2008/11/25 02:59:29 kensmith Exp $
30 * Alias_mod.h defines the outside world interfaces for the packet aliasing
38 /* Protocol handlers struct & function. */
40 /* Packet flow direction. */
44 /* Working protocol. */
50 * Data passed to protocol handler module, it must be filled
51 * right before calling find_handler() to determine which
52 * module is elegible to be called.
56 struct alias_link *lnk;
57 struct in_addr *oaddr; /* Original address. */
58 struct in_addr *aaddr; /* Alias address. */
59 uint16_t *aport; /* Alias port. */
60 uint16_t *sport, *dport; /* Source & destination port */
61 uint16_t maxpktsize; /* Max packet size. */
65 * This structure contains all the information necessary to make
66 * a protocol handler correctly work.
69 struct proto_handler {
70 u_int pri; /* Handler priority. */
71 int16_t dir; /* Flow direction. */
72 uint8_t proto; /* Working protocol. */
73 int (*fingerprint)(struct libalias *la, /* Fingerprint * function. */
74 struct ip *pip, struct alias_data *ah);
75 int (*protohandler)(struct libalias *la, /* Aliasing * function. */
76 struct ip *pip, struct alias_data *ah);
77 LIST_ENTRY(proto_handler) entries;
82 * Used only in userland when libalias needs to keep track of all
83 * module loaded. In kernel land (kld mode) we don't need to care
84 * care about libalias modules cause it's kld to do it for us.
89 char name[DLL_LEN]; /* Name of module. */
91 * Ptr to shared obj obtained through
92 * dlopen() - use this ptr to get access
93 * to any symbols from a loaded module
96 SLIST_ENTRY(dll) next;
99 /* Functions used with protocol handlers. */
101 void handler_chain_init(void);
102 void handler_chain_destroy(void);
103 int LibAliasAttachHandlers(struct proto_handler *);
104 int LibAliasDetachHandlers(struct proto_handler *);
105 int detach_handler(struct proto_handler *);
106 int find_handler(int8_t, int8_t, struct libalias *,
107 struct ip *, struct alias_data *);
108 struct proto_handler *first_handler(void);
110 /* Functions used with dll module. */
112 void dll_chain_init(void);
113 void dll_chain_destroy(void);
114 int attach_dll(struct dll *);
115 void *detach_dll(char *);
116 struct dll *walk_dll_chain(void);
118 /* End of handlers. */
122 * Some defines borrowed from sys/module.h used to compile a kld
123 * in userland as a shared lib.
129 typedef enum modeventtype {
136 typedef struct module *module_t;
137 typedef int (*modeventhand_t)(module_t, int /* modeventtype_t */, void *);
140 * Struct for registering modules statically via SYSINIT.
142 typedef struct moduledata {
143 const char *name; /* module name */
144 modeventhand_t evhand; /* event handler */
145 void *priv; /* extra data */
149 #endif /* !_ALIAS_MOD_H_ */