1
2%{
3/*
4 * Copyright (C) 2012 by Darren Reed.
5 *
6 * See the IPFILTER.LICENCE file for details on licencing.
7 *
8 * $Id$
9 */
10#include <stdio.h>
11#include <string.h>
12#include <sys/param.h>
13#if defined(__SVR4) || defined(__sysv__)
14#include <sys/stream.h>
15#endif
16#include <sys/types.h>
17#include <netinet/in_systm.h>
18#include <netinet/in.h>
19#include "iplang_y.h"
20#include "ipf.h"
21
22#ifndef	__P
23#  define	__P(x)	x
24#endif
25
26extern int opts;
27
28int lineNum = 0, ipproto = 0, oldipproto = 0, next = -1, laststate = 0;
29int *prstack = NULL, numpr = 0, state = 0, token = 0;
30
31void    yyerror(char *);
32void	push_proto(void);
33void	pop_proto(void);
34int	next_state(int, int);
35int	next_item(int);
36int	save_token(void);
37void	swallow(void);
38int	yylex(void);
39
40struct	lwordtab	{
41	char	*word;
42	int	state;
43	int	next;
44};
45
46struct	lwordtab	words[] = {
47	{ "interface",	IL_INTERFACE,		-1 },
48	{ "iface",	IL_INTERFACE,		-1 },
49	{ "name",	IL_IFNAME,		IL_TOKEN },
50	{ "ifname",	IL_IFNAME,		IL_TOKEN },
51	{ "router",	IL_DEFROUTER,		IL_TOKEN },
52	{ "mtu",	IL_MTU,			IL_NUMBER },
53	{ "eaddr",	IL_EADDR,		IL_TOKEN },
54	{ "v4addr",	IL_V4ADDR,		IL_TOKEN },
55	{ "ipv4",	IL_IPV4,		-1 },
56	{ "v",		IL_V4V,			IL_TOKEN },
57	{ "proto",	IL_V4PROTO,		IL_TOKEN },
58	{ "hl",		IL_V4HL,		IL_TOKEN },
59	{ "id",		IL_V4ID,		IL_TOKEN },
60	{ "ttl",	IL_V4TTL,		IL_TOKEN },
61	{ "tos",	IL_V4TOS,		IL_TOKEN },
62	{ "src",	IL_V4SRC,		IL_TOKEN },
63	{ "dst",	IL_V4DST,		IL_TOKEN },
64	{ "opt",	IL_OPT,			-1 },
65	{ "len",	IL_LEN,			IL_TOKEN },
66	{ "off",	IL_OFF,			IL_TOKEN },
67	{ "sum",	IL_SUM,			IL_TOKEN },
68	{ "tcp",	IL_TCP,			-1 },
69	{ "sport",	IL_SPORT,		IL_TOKEN },
70	{ "dport",	IL_DPORT,		IL_TOKEN },
71	{ "seq",	IL_TCPSEQ,		IL_TOKEN },
72	{ "ack",	IL_TCPACK,		IL_TOKEN },
73	{ "flags",	IL_TCPFL,		IL_TOKEN },
74	{ "urp",	IL_TCPURP,		IL_TOKEN },
75	{ "win",	IL_TCPWIN,		IL_TOKEN },
76	{ "udp",	IL_UDP,			-1 },
77	{ "send",	IL_SEND,		-1 },
78	{ "via",	IL_VIA,			IL_TOKEN },
79	{ "arp",	IL_ARP,			-1 },
80	{ "data",	IL_DATA,		-1 },
81	{ "value",	IL_DVALUE,		IL_TOKEN },
82	{ "file",	IL_DFILE,		IL_TOKEN },
83	{ "nop",	IL_IPO_NOP,		-1 },
84	{ "eol",	IL_IPO_EOL,		-1 },
85	{ "rr",		IL_IPO_RR,		-1 },
86	{ "zsu",	IL_IPO_ZSU,		-1 },
87	{ "mtup",	IL_IPO_MTUP,		-1 },
88	{ "mtur",	IL_IPO_MTUR,		-1 },
89	{ "encode",	IL_IPO_ENCODE,		-1 },
90	{ "ts",		IL_IPO_TS,		-1 },
91	{ "tr",		IL_IPO_TR,		-1 },
92	{ "sec",	IL_IPO_SEC,		-1 },
93	{ "secclass",	IL_IPO_SECCLASS,	IL_TOKEN },
94	{ "lsrr",	IL_IPO_LSRR,		-1 },
95	{ "esec",	IL_IPO_ESEC,		-1 },
96	{ "cipso",	IL_IPO_CIPSO,		-1 },
97	{ "satid",	IL_IPO_SATID,		-1 },
98	{ "ssrr",	IL_IPO_SSRR,		-1 },
99	{ "addext",	IL_IPO_ADDEXT,		-1 },
100	{ "visa",	IL_IPO_VISA,		-1 },
101	{ "imitd",	IL_IPO_IMITD,		-1 },
102	{ "eip",	IL_IPO_EIP,		-1 },
103	{ "finn",	IL_IPO_FINN,		-1 },
104	{ "mss",	IL_TCPO_MSS,		IL_TOKEN },
105	{ "wscale",	IL_TCPO_WSCALE,		IL_TOKEN },
106	{ "reserv-4",	IL_IPS_RESERV4,		-1 },
107	{ "topsecret",	IL_IPS_TOPSECRET,	-1 },
108	{ "secret",	IL_IPS_SECRET,		-1 },
109	{ "reserv-3",	IL_IPS_RESERV3,		-1 },
110	{ "confid",	IL_IPS_CONFID,		-1 },
111	{ "unclass",	IL_IPS_UNCLASS,		-1 },
112	{ "reserv-2",	IL_IPS_RESERV2,		-1 },
113	{ "reserv-1",	IL_IPS_RESERV1,		-1 },
114	{ "icmp",	IL_ICMP,		-1 },
115	{ "type",	IL_ICMPTYPE,		-1 },
116	{ "code",	IL_ICMPCODE,		-1 },
117	{ "echorep",	IL_ICMP_ECHOREPLY,	-1 },
118	{ "unreach",	IL_ICMP_UNREACH,	-1 },
119	{ "squench",	IL_ICMP_SOURCEQUENCH,	-1 },
120	{ "redir",	IL_ICMP_REDIRECT,	-1 },
121	{ "echo",	IL_ICMP_ECHO,		-1 },
122	{ "routerad",	IL_ICMP_ROUTERADVERT,	-1 },
123	{ "routersol",	IL_ICMP_ROUTERSOLICIT,	-1 },
124	{ "timex",	IL_ICMP_TIMXCEED,	-1 },
125	{ "paramprob",	IL_ICMP_PARAMPROB,	-1 },
126	{ "timest",	IL_ICMP_TSTAMP,		-1 },
127	{ "timestrep",	IL_ICMP_TSTAMPREPLY,	-1 },
128	{ "inforeq",	IL_ICMP_IREQ,		-1 },
129	{ "inforep",	IL_ICMP_IREQREPLY,	-1 },
130	{ "maskreq",	IL_ICMP_MASKREQ,	-1 },
131	{ "maskrep",	IL_ICMP_MASKREPLY,	-1 },
132	{ "net-unr",	IL_ICMP_UNREACH_NET,	-1 },
133	{ "host-unr",	IL_ICMP_UNREACH_HOST,	-1 },
134	{ "proto-unr",	IL_ICMP_UNREACH_PROTOCOL,	-1 },
135	{ "port-unr",	IL_ICMP_UNREACH_PORT,	-1 },
136	{ "needfrag",	IL_ICMP_UNREACH_NEEDFRAG,	-1 },
137	{ "srcfail",	IL_ICMP_UNREACH_SRCFAIL,	-1 },
138	{ "net-unk",	IL_ICMP_UNREACH_NET_UNKNOWN,	-1 },
139	{ "host-unk",	IL_ICMP_UNREACH_HOST_UNKNOWN,	-1 },
140	{ "isolate",	IL_ICMP_UNREACH_ISOLATED,	-1 },
141	{ "net-prohib",	IL_ICMP_UNREACH_NET_PROHIB,	-1 },
142	{ "host-prohib",	IL_ICMP_UNREACH_HOST_PROHIB,	-1 },
143	{ "net-tos",	IL_ICMP_UNREACH_TOSNET,	-1 },
144	{ "host-tos",	IL_ICMP_UNREACH_TOSHOST,	-1 },
145	{ "filter-prohib",	IL_ICMP_UNREACH_FILTER_PROHIB,	-1 },
146	{ "host-preced",	IL_ICMP_UNREACH_HOST_PRECEDENCE,	-1 },
147	{ "cutoff-preced",	IL_ICMP_UNREACH_PRECEDENCE_CUTOFF,	-1 },
148	{ "net-redir",	IL_ICMP_REDIRECT_NET,	-1 },
149	{ "host-redir",	IL_ICMP_REDIRECT_HOST,	-1 },
150	{ "tos-net-redir",	IL_ICMP_REDIRECT_TOSNET,	-1 },
151	{ "tos-host-redir",	IL_ICMP_REDIRECT_TOSHOST,	-1 },
152	{ "intrans",	IL_ICMP_TIMXCEED_INTRANS,	-1 },
153	{ "reass",	IL_ICMP_TIMXCEED_REASS,	-1 },
154	{ "optabsent",	IL_ICMP_PARAMPROB_OPTABSENT,	-1 },
155	{ "otime",	IL_ICMP_OTIME,		-1 },
156	{ "rtime",	IL_ICMP_RTIME,		-1 },
157	{ "ttime",	IL_ICMP_TTIME,		-1 },
158	{ "icmpseq",	IL_ICMP_SEQ,		-1 },
159	{ "icmpid",	IL_ICMP_SEQ,		-1 },
160	{ ".",		IL_DOT,			-1 },
161	{ NULL, 0, 0 }
162};
163%}
164white	[ \t\r]+
165%%
166{white}	;
167\n	{ lineNum++; swallow(); }
168\{	{( push_proto(); return next_item('{'); });
169\}	{( pop_proto(); return next_item('}'); });
170;	{( return next_item(';'); });
171[0-9]+	{( return next_item(IL_NUMBER); });
172[0-9a-fA-F]	{( return next_item(IL_HEXDIGIT); });
173:	{( return next_item(IL_COLON); });
174#[^\n]*	{( return next_item(IL_COMMENT); });
175[^( \{\}\n\t;:{}]*	{ return next_item(IL_TOKEN); });
176\"[^\"]*\"	{( return next_item(IL_TOKEN); });
177%%
178void    yyerror(msg)
179char    *msg;
180{
181	fprintf(stderr, "%s error at \"%s\", line %d\n", msg, yytext,
182		lineNum + 1);
183	exit(1);
184}
185
186
187void push_proto(void)
188{
189	numpr++;
190	if (!prstack)
191		prstack = (int *)malloc(sizeof(int));
192	else
193		prstack = (int *)reallocarray((char *)prstack, numpr,
194		    sizeof(int));
195	prstack[numpr - 1] = oldipproto;
196}
197
198
199void pop_proto(void)
200{
201	numpr--;
202	ipproto = prstack[numpr];
203	if (!numpr) {
204		free(prstack);
205		prstack = NULL;
206		return;
207	}
208	prstack = (int *)realloc((char *)prstack, numpr * sizeof(int));
209}
210
211
212int save_token(void)
213{
214
215	yylval.str = strdup((char *)yytext);
216	return(IL_TOKEN);
217}
218
219
220int next_item(int nstate)
221{
222	struct	lwordtab	*wt;
223
224	if (opts & OPT_DEBUG)
225		printf("text=[%s] id=%d next=%d\n", yytext, nstate, next);
226	if (next == IL_TOKEN) {
227		next = -1;
228		return(save_token());
229	}
230	token++;
231
232	for (wt = words; wt->word; wt++)
233		if (!strcasecmp(wt->word, (char *)yytext))
234			return(next_state(wt->state, wt->next));
235	if (opts & OPT_DEBUG)
236		printf("unknown keyword=[%s]\n", yytext);
237	next = -1;
238	if (nstate == IL_NUMBER)
239		yylval.num = atoi((char *)yytext);
240	token++;
241	return(nstate);
242}
243
244
245int next_state(int nstate, int fornext)
246{
247	next = fornext;
248
249	switch (nstate)
250	{
251	case IL_IPV4 :
252	case IL_TCP :
253	case IL_UDP :
254	case IL_ICMP :
255	case IL_DATA :
256	case IL_INTERFACE :
257	case IL_ARP :
258		oldipproto = ipproto;
259		ipproto = nstate;
260		break;
261	case IL_SUM :
262		if (ipproto == IL_IPV4)
263			nstate = IL_V4SUM;
264		else if (ipproto == IL_TCP)
265			nstate = IL_TCPSUM;
266		else if (ipproto == IL_UDP)
267			nstate = IL_UDPSUM;
268		break;
269	case IL_OPT :
270		if (ipproto == IL_IPV4)
271			nstate = IL_V4OPT;
272		else if (ipproto == IL_TCP)
273			nstate = IL_TCPOPT;
274		break;
275	case IL_IPO_NOP :
276		if (ipproto == IL_TCP)
277			nstate = IL_TCPO_NOP;
278		break;
279	case IL_IPO_EOL :
280		if (ipproto == IL_TCP)
281			nstate = IL_TCPO_EOL;
282		break;
283	case IL_IPO_TS :
284		if (ipproto == IL_TCP)
285			nstate = IL_TCPO_TS;
286		break;
287	case IL_OFF :
288		if (ipproto == IL_IPV4)
289			nstate = IL_V4OFF;
290		else if (ipproto == IL_TCP)
291			nstate = IL_TCPOFF;
292		break;
293	case IL_LEN :
294		if (ipproto == IL_IPV4)
295			nstate = IL_V4LEN;
296		else if (ipproto == IL_UDP)
297			nstate = IL_UDPLEN;
298		break;
299	}
300	return(nstate);
301}
302
303
304void swallow(void)
305{
306	int c;
307
308	c = input();
309
310	if (c == '#') {
311		while ((c != '\n') && (c != EOF))
312			c = input();
313	}
314	if (c != EOF)
315		unput(c);
316}
317