summaryrefslogtreecommitdiffstats
path: root/freebsd/sys/netinet/libalias/alias_mod.h
blob: a894b6def71a79eac7fd287ef4c1b86196bc7bc3 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * 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_)
#undef malloc
#ifndef __rtems__
#define	malloc(x)	malloc(x, M_ALIAS, M_NOWAIT|M_ZERO)
#define	calloc(n, x)	mallocarray((n), (x), M_ALIAS, M_NOWAIT|M_ZERO)
#define	free(x)		free(x, M_ALIAS)
#else /* __rtems__ */
#undef calloc
#undef free
#define malloc(x)	_bsd_malloc(x, M_ALIAS, M_NOWAIT|M_ZERO)
#define	calloc(n, x)	mallocarray((n), (x), M_ALIAS, M_NOWAIT|M_ZERO)
#define free(x)		_bsd_free(x, M_ALIAS)
#endif /* __rtems__ */
#endif
#endif

/* Packet flow direction flags. */
#define IN	0x0001
#define OUT	0x0002
#define	NODIR	0x4000

/* Working protocol flags. */
#define IP	0x01
#define TCP	0x02
#define UDP	0x04

/*
 * 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. */
	/* Fingerprint * function. */
	int (*fingerprint)(struct libalias *, struct alias_data *);
	/* Aliasing * function. */
	int (*protohandler)(struct libalias *, struct ip *,
	    struct alias_data *);
	TAILQ_ENTRY(proto_handler) link;
};

/* End of handlers. */
#define EOH	.dir = NODIR

/* Functions used with protocol handlers. */
int LibAliasAttachHandlers(struct proto_handler *);
int LibAliasDetachHandlers(struct proto_handler *);
int find_handler(int8_t, int8_t, struct libalias *, struct ip *,
    struct alias_data *);
struct proto_handler *first_handler(void);

#ifndef _KERNEL
/*
 * 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 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);

/*
 * Some defines borrowed from sys/module.h used to compile a kld
 * in userland as a shared lib.
 */
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 /* !_KERNEL */

#endif /* !_ALIAS_MOD_H_ */