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/* types and functions used throughout filtergen
*
* Copyright (c) 2002 Matthew Kirkwood
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _FK_FILTER_H
#define _FK_FILTER_H
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#ifdef __GNUC__
#define _PRINTF_ATTR(s,e) __attribute__ ((__format__(__printf__, (s), (e))))
#else
#define _PRINTF_ATTR(s,e)
#endif
/*
* If it doesn't begin with "F_", it's a simple token, not an
* filter type
*/
enum filtertype {
YYEOF = 0,
F_DIRECTION, F_TARGET,
F_SOURCE, F_DEST, F_SPORT, F_DPORT,
F_ICMPTYPE,
F_PROTO,
F_NEG, F_SIBLIST, F_SUBGROUP,
F_LOG,
F_RTYPE,
F_ONEWAY,
/* this must be the last real filter type */
F_FILTER_MAX,
/* parser use only */
INPUT, OUTPUT,
/* lex uses "ACCEPT" and "REJECT" */
T_ACCEPT, DROP, T_REJECT,
MASQ, REDIRECT,
OPENBRACE, CLOSEBRACE,
OPENBRACKET, CLOSEBRACKET,
SEMICOLON, STRING,
INCLUDE,
LOCALONLY, ROUTEDONLY, /* for F_RTYPE */
TEXT, /* for F_LOG */
};
/* Structures which appear in both the parse tree and the output rule */
struct proto_spec {
int num;
char *name;
};
struct addr_spec {
struct in_addr addr, mask;
char *addrstr, *maskstr;
};
struct port_spec {
int min, max;
char *minstr, *maxstr;
};
/* This is basically just a parse tree */
struct filter {
enum filtertype type;
union {
struct {
enum filtertype direction;
char *iface;
} ifinfo;
enum filtertype target;
char *logmsg;
enum filtertype rtype;
struct addr_spec addrs;
struct port_spec ports;
char *icmp;
struct proto_spec proto;
struct filter *neg;
struct filter *sib;
struct {
char *name;
struct filter *list;
} sub;
} u;
struct filter *child, *next;
/* infernal use only */
int negate;
};
/* from filter.c */
typedef struct filter *filter_tctor(enum filtertype);
filter_tctor new_filter_target, new_filter_rtype;
struct filter *new_filter_neg(struct filter *sub);
struct filter *new_filter_sibs(struct filter *list);
struct filter *new_filter_subgroup(char *name, struct filter *list);
typedef struct filter *filter_ctor(enum filtertype, const char*);
filter_ctor new_filter_device, new_filter_host, new_filter_ports, new_filter_icmp, new_filter_proto, new_filter_log;
struct filter *new_filter_oneway(void);
/* filter manipulations */
void filter_unroll(struct filter **f);
void filter_nogroup(struct filter *f);
void filter_noneg(struct filter **f);
void filter_apply_flags(struct filter *f, long flags);
/* from generated lexer and parer in filterlex.l */
int filter_fopen(const char *filename);
struct filter *filter_parse_list(void);
/* from gen.c */
#define ESET(e,f) (e->whats_set & (1 << F_ ##f))
struct filterent {
/* Either direction+iface or groupname must be set */
enum filtertype direction;
char *iface;
char *groupname;
/* One of these must be set */
enum filtertype target;
char *subgroup;
/* These may or may not be set */
int whats_set:F_FILTER_MAX;
int whats_negated:F_FILTER_MAX;
struct addr_spec srcaddr, dstaddr;
enum filtertype rtype;
struct proto_spec proto;
char *logmsg;
int oneway;
/* We need this not to be a union, for error-checking reasons */
struct {
struct {
struct port_spec src, dst;
} ports;
char *icmp;
} u;
};
struct fg_misc {
int flags;
void *misc;
};
typedef int fg_cb_rule(const struct filterent *ent, struct fg_misc *misc);
typedef int fg_cb_group(const char *name);
typedef struct {
fg_cb_rule *rule;
fg_cb_group *group;
} fg_callback;
int filtergen_cprod(struct filter *filter, fg_callback *cb, struct fg_misc *misc);
/* fg-util.c */
char *strapp(char *s, const char *n);
#define strapp2(s,n1,n2) strapp(strapp(s,n1),n2)
int str_to_int(const char *s, int *i);
char *int_to_str_dup(int i);
/* various drivers */
typedef int filtergen(struct filter *filter, int flags);
filtergen fg_iptables, fg_ipchains, fg_ipfilter, fg_cisco;
typedef int filter_flush(enum filtertype policy);
filter_flush flush_iptables, flush_ipchains;
/* ("flags" arguments) */
#define FF_NOSKEL (1 << 0) /* omit any "skeleton" rules */
#define FF_LSTATE (1 << 1) /* lightweight state matching */
#define FF_LOCAL (1 << 2) /* assume packets are local only */
#define FF_ROUTE (1 << 3) /* assume packets are forwarded */
#define FF_LOOKUP (1 << 4) /* translate host and service names into
* IP addresses and port numbers */
#define FF_FLUSH (1 << 5) /* just flush the ruleset instead */
/* filtergen.c */
int oputs(const char *s);
int oprintf(const char *fmt, ...) _PRINTF_ATTR(1,2);
#endif /* _FK_FILTER_H */
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