xref: /freebsd/sbin/ipf/iplang/iplang_l.l (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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 
26 extern int opts;
27 
28 int lineNum = 0, ipproto = 0, oldipproto = 0, next = -1, laststate = 0;
29 int *prstack = NULL, numpr = 0, state = 0, token = 0;
30 
31 void    yyerror(char *);
32 void	push_proto(void);
33 void	pop_proto(void);
34 int	next_state(int, int);
35 int	next_item(int);
36 int	save_token(void);
37 void	swallow(void);
38 int	yylex(void);
39 
40 struct	lwordtab	{
41 	char	*word;
42 	int	state;
43 	int	next;
44 };
45 
46 struct	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 %}
164 white	[ \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 %%
178 void    yyerror(msg)
179 char    *msg;
180 {
181 	fprintf(stderr, "%s error at \"%s\", line %d\n", msg, yytext,
182 		lineNum + 1);
183 	exit(1);
184 }
185 
186 
187 void 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 
199 void 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 
212 int save_token(void)
213 {
214 
215 	yylval.str = strdup((char *)yytext);
216 	return(IL_TOKEN);
217 }
218 
219 
220 int 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 
245 int 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 
304 void 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