xref: /openbsd-src/usr.sbin/ripctl/parser.c (revision 33a9ef426717cea0731f7d9607264e1db814a61a)
1 /*	$OpenBSD: parser.c,v 1.7 2017/07/28 13:02:35 florian Exp $ */
2 
3 /*
4  * Copyright (c) 2006 Michele Marchetto <mydecay@openbeer.it>
5  * Copyright (c) 2004 Esben Norby <norby@openbsd.org>
6  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
7  *
8  * Permission to use, copy, modify, and distribute this software for any
9  * purpose with or without fee is hereby granted, provided that the above
10  * copyright notice and this permission notice appear in all copies.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19  */
20 
21 #include <sys/types.h>
22 #include <sys/socket.h>
23 #include <netinet/in.h>
24 #include <arpa/inet.h>
25 #include <err.h>
26 #include <errno.h>
27 #include <limits.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 
32 #include "ripd.h"
33 
34 #include "parser.h"
35 
36 enum token_type {
37 	NOTOKEN,
38 	ENDTOKEN,
39 	KEYWORD,
40 	ADDRESS,
41 	FLAG,
42 	PREFIX,
43 	IFNAME
44 };
45 
46 struct token {
47 	enum token_type		 type;
48 	const char		*keyword;
49 	int			 value;
50 	const struct token	*next;
51 };
52 
53 static const struct token t_main[];
54 static const struct token t_fib[];
55 static const struct token t_show[];
56 static const struct token t_show_iface[];
57 static const struct token t_show_nbr[];
58 static const struct token t_show_rib[];
59 static const struct token t_show_fib[];
60 static const struct token t_log[];
61 
62 static const struct token t_main[] = {
63 /*	{KEYWORD,	"reload",	RELOAD,		NULL}, */
64 	{KEYWORD,	"fib",		FIB,		t_fib},
65 	{KEYWORD,	"show",		SHOW,		t_show},
66 	{KEYWORD,	"log",		NONE,		t_log},
67 	{ENDTOKEN,	"",		NONE,		NULL}
68 };
69 
70 static const struct token t_fib[] = {
71 	{ KEYWORD,	"couple",	FIB_COUPLE,	NULL},
72 	{ KEYWORD,	"decouple",	FIB_DECOUPLE,	NULL},
73 	{ ENDTOKEN,	"",		NONE,		NULL}
74 };
75 
76 static const struct token t_show[] = {
77 	{NOTOKEN,	"",		NONE,		NULL},
78 	{KEYWORD,	"interfaces",	SHOW_IFACE,	t_show_iface},
79 	{KEYWORD,	"neighbor",	SHOW_NBR,	t_show_nbr},
80 	{KEYWORD,	"rib",		SHOW_RIB,	t_show_rib},
81 	{KEYWORD,	"fib",		SHOW_FIB,	t_show_fib},
82 	{ENDTOKEN,	"",		NONE,		NULL}
83 };
84 
85 static const struct token t_show_iface[] = {
86 	{NOTOKEN,	"",		NONE,			NULL},
87 	{ENDTOKEN,	"",		NONE,			NULL}
88 };
89 
90 static const struct token t_show_nbr[] = {
91 	{NOTOKEN,	"",		NONE,		NULL},
92 	{ENDTOKEN,	"",		NONE,		NULL}
93 };
94 
95 static const struct token t_show_rib[] = {
96 	{NOTOKEN,	"",		NONE,		NULL},
97 	{ENDTOKEN,	"",		NONE,		NULL}
98 };
99 
100 static const struct token t_show_fib[] = {
101 	{NOTOKEN,	"",		NONE,			NULL},
102 	{KEYWORD,	"interface",	SHOW_FIB_IFACE,		t_show_iface},
103 	{FLAG,		"connected",	F_CONNECTED,		t_show_fib},
104 	{FLAG,		"static",	F_STATIC,		t_show_fib},
105 	{FLAG,		"rip",		F_RIPD_INSERTED,	t_show_fib},
106 	{ADDRESS,	"",		NONE,			NULL},
107 	{ENDTOKEN,	"",		NONE,			NULL}
108 };
109 
110 static const struct token t_log[] = {
111 	{KEYWORD,	"verbose",	LOG_VERBOSE,		NULL},
112 	{KEYWORD,	"brief",	LOG_BRIEF,		NULL},
113 	{ENDTOKEN,	"",		NONE,			NULL}
114 };
115 
116 static const struct token *match_token(const char *, const struct token *,
117     struct parse_result *);
118 static void show_valid_args(const struct token *table);
119 
120 struct parse_result *
parse(int argc,char * argv[])121 parse(int argc, char *argv[])
122 {
123 	static struct parse_result res;
124 	const struct token	*table = t_main;
125 	const struct token	*match;
126 
127 	bzero(&res, sizeof(res));
128 
129 	while (argc >= 0) {
130 		if ((match = match_token(argv[0], table, &res)) == NULL) {
131 			fprintf(stderr, "valid commands/args:\n");
132 			show_valid_args(table);
133 			return (NULL);
134 		}
135 
136 		argc--;
137 		argv++;
138 
139 		if (match->type == NOTOKEN || match->next == NULL)
140 			break;
141 
142 		table = match->next;
143 	}
144 
145 	if (argc > 0) {
146 		fprintf(stderr, "superfluous argument: %s\n", argv[0]);
147 		return (NULL);
148 	}
149 
150 	return (&res);
151 }
152 
153 static const struct token *
match_token(const char * word,const struct token * table,struct parse_result * res)154 match_token(const char *word, const struct token *table,
155     struct parse_result *res)
156 {
157 	u_int			 i, match;
158 	const struct token	*t = NULL;
159 
160 	match = 0;
161 
162 	for (i = 0; table[i].type != ENDTOKEN; i++) {
163 		switch (table[i].type) {
164 		case NOTOKEN:
165 			if (word == NULL || strlen(word) == 0) {
166 				match++;
167 				t = &table[i];
168 			}
169 			break;
170 		case KEYWORD:
171 			if (word != NULL && strncmp(word, table[i].keyword,
172 			    strlen(word)) == 0) {
173 				match++;
174 				t = &table[i];
175 				if (t->value)
176 					res->action = t->value;
177 			}
178 			break;
179 		case FLAG:
180 			if (word != NULL && strncmp(word, table[i].keyword,
181 			    strlen(word)) == 0) {
182 				match++;
183 				t = &table[i];
184 				res->flags |= t->value;
185 			}
186 			break;
187 		case ADDRESS:
188 			if (parse_addr(word, &res->addr)) {
189 				match++;
190 				t = &table[i];
191 				if (t->value)
192 					res->action = t->value;
193 			}
194 			break;
195 		case PREFIX:
196 			if (parse_prefix(word, &res->addr, &res->prefixlen)) {
197 				match++;
198 				t = &table[i];
199 				if (t->value)
200 					res->action = t->value;
201 			}
202 			break;
203 		case IFNAME:
204 			if (!match && word != NULL && strlen(word) > 0) {
205 				if (strlcpy(res->ifname, word,
206 				    sizeof(res->ifname)) >=
207 				    sizeof(res->ifname))
208 					err(1, "interface name too long");
209 				match++;
210 				t = &table[i];
211 				if (t->value)
212 					res->action = t->value;
213 			}
214 			break;
215 
216 		case ENDTOKEN:
217 			break;
218 		}
219 	}
220 
221 	if (match != 1) {
222 		if (word == NULL)
223 			fprintf(stderr, "missing argument:\n");
224 		else if (match > 1)
225 			fprintf(stderr, "ambiguous argument: %s\n", word);
226 		else if (match < 1)
227 			fprintf(stderr, "unknown argument: %s\n", word);
228 		return (NULL);
229 	}
230 
231 	return (t);
232 }
233 
234 static void
show_valid_args(const struct token * table)235 show_valid_args(const struct token *table)
236 {
237 	int	i;
238 
239 	for (i = 0; table[i].type != ENDTOKEN; i++) {
240 		switch (table[i].type) {
241 		case NOTOKEN:
242 			fprintf(stderr, "  <cr>\n");
243 			break;
244 		case KEYWORD:
245 		case FLAG:
246 			fprintf(stderr, "  %s\n", table[i].keyword);
247 			break;
248 		case ADDRESS:
249 			fprintf(stderr, "  <address>\n");
250 			break;
251 		case PREFIX:
252 			fprintf(stderr, "  <address>[/<len>]\n");
253 			break;
254 		case IFNAME:
255 			fprintf(stderr, "  <interface>\n");
256 		case ENDTOKEN:
257 			break;
258 		}
259 	}
260 }
261 
262 int
parse_addr(const char * word,struct in_addr * addr)263 parse_addr(const char *word, struct in_addr *addr)
264 {
265 	struct in_addr	ina;
266 
267 	if (word == NULL)
268 		return (0);
269 
270 	bzero(addr, sizeof(struct in_addr));
271 	bzero(&ina, sizeof(ina));
272 
273 	if (inet_pton(AF_INET, word, &ina)) {
274 		addr->s_addr = ina.s_addr;
275 		return (1);
276 	}
277 
278 	return (0);
279 }
280 
281 int
parse_prefix(const char * word,struct in_addr * addr,u_int8_t * prefixlen)282 parse_prefix(const char *word, struct in_addr *addr, u_int8_t *prefixlen)
283 {
284 	struct in_addr	 ina;
285 	int		 bits = 32;
286 
287 	if (word == NULL)
288 		return (0);
289 
290 	bzero(addr, sizeof(struct in_addr));
291 	bzero(&ina, sizeof(ina));
292 
293 	if (strrchr(word, '/') != NULL) {
294 		if ((bits = inet_net_pton(AF_INET, word,
295 		    &ina, sizeof(ina))) == -1)
296 			return (0);
297 		addr->s_addr = ina.s_addr & htonl(prefixlen2mask(bits));
298 		*prefixlen = bits;
299 		return (1);
300 	} else {
301 		*prefixlen = 32;
302 		return (parse_addr(word, addr));
303 	}
304 
305 	return (0);
306 }
307 
308 /* XXX local copy from kroute.c, should go to shared file */
309 in_addr_t
prefixlen2mask(u_int8_t prefixlen)310 prefixlen2mask(u_int8_t prefixlen)
311 {
312 	if (prefixlen == 0)
313 		return (0);
314 
315 	return (0xffffffff << (32 - prefixlen));
316 }
317