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/*-
* Copyright (c) 2005 Paolo Pisati <piso@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* Alias_mod.h defines the outside world interfaces for the packet aliasing
* modular framework
*/
#ifndef _ALIAS_MOD_H_
#define _ALIAS_MOD_H_
#ifdef _KERNEL
MALLOC_DECLARE(M_ALIAS);
/* Use kernel allocator. */
#if defined(_SYS_MALLOC_H_)
#define malloc(x) malloc(x, M_ALIAS, M_NOWAIT|M_ZERO)
#define calloc(x, n) malloc(x*n)
#define free(x) free(x, M_ALIAS)
#endif
#endif
/* Protocol handlers struct & function. */
/* Packet flow direction. */
#define IN 1
#define OUT 2
/* Working protocol. */
#define IP 1
#define TCP 2
#define UDP 4
/*
* Data passed to protocol handler module, it must be filled
* right before calling find_handler() to determine which
* module is elegible to be called.
*/
struct alias_data {
struct alias_link *lnk;
struct in_addr *oaddr; /* Original address. */
struct in_addr *aaddr; /* Alias address. */
uint16_t *aport; /* Alias port. */
uint16_t *sport, *dport; /* Source & destination port */
uint16_t maxpktsize; /* Max packet size. */
};
/*
* This structure contains all the information necessary to make
* a protocol handler correctly work.
*/
struct proto_handler {
u_int pri; /* Handler priority. */
int16_t dir; /* Flow direction. */
uint8_t proto; /* Working protocol. */
int (*fingerprint)(struct libalias *, /* Fingerprint * function. */
struct alias_data *);
int (*protohandler)(struct libalias *, /* Aliasing * function. */
struct ip *, struct alias_data *);
LIST_ENTRY(proto_handler) entries;
};
/*
* Used only in userland when libalias needs to keep track of all
* module loaded. In kernel land (kld mode) we don't need to care
* care about libalias modules cause it's kld to do it for us.
*/
#define DLL_LEN 32
struct dll {
char name[DLL_LEN]; /* Name of module. */
void *handle; /*
* Ptr to shared obj obtained through
* dlopen() - use this ptr to get access
* to any symbols from a loaded module
* via dlsym().
*/
SLIST_ENTRY(dll) next;
};
/* Functions used with protocol handlers. */
void handler_chain_init(void);
void handler_chain_destroy(void);
int LibAliasAttachHandlers(struct proto_handler *);
int LibAliasDetachHandlers(struct proto_handler *);
int detach_handler(struct proto_handler *);
int find_handler(int8_t, int8_t, struct libalias *,
struct ip *, struct alias_data *);
struct proto_handler *first_handler(void);
/* Functions used with dll module. */
void dll_chain_init(void);
void dll_chain_destroy(void);
int attach_dll(struct dll *);
void *detach_dll(char *);
struct dll *walk_dll_chain(void);
/* End of handlers. */
#define EOH -1
/*
* Some defines borrowed from sys/module.h used to compile a kld
* in userland as a shared lib.
*/
#ifndef _KERNEL
typedef enum modeventtype {
MOD_LOAD,
MOD_UNLOAD,
MOD_SHUTDOWN,
MOD_QUIESCE
} modeventtype_t;
typedef struct module *module_t;
typedef int (*modeventhand_t)(module_t, int /* modeventtype_t */, void *);
/*
* Struct for registering modules statically via SYSINIT.
*/
typedef struct moduledata {
const char *name; /* module name */
modeventhand_t evhand; /* event handler */
void *priv; /* extra data */
} moduledata_t;
#endif
#endif /* !_ALIAS_MOD_H_ */
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