xref: /openbsd-src/usr.sbin/dvmrpctl/parser.c (revision 2b0358df1d88d06ef4139321dd05bd5e05d91eaf)
1 /*	$OpenBSD: parser.c,v 1.2 2007/01/26 09:55:02 claudio Exp $ */
2 
3 /*
4  * Copyright (c) 2004, 2005, 2006 Esben Norby <norby@openbsd.org>
5  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/types.h>
21 #include <sys/socket.h>
22 #include <netinet/in.h>
23 #include <arpa/inet.h>
24 #include <err.h>
25 #include <errno.h>
26 #include <limits.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 
31 #include "dvmrpd.h"
32 #include "parser.h"
33 
34 enum token_type {
35 	NOTOKEN,
36 	ENDTOKEN,
37 	KEYWORD,
38 	ADDRESS,
39 	FLAG,
40 	PREFIX,
41 	IFNAME
42 };
43 
44 struct token {
45 	enum token_type		 type;
46 	const char		*keyword;
47 	int			 value;
48 	const struct token	*next;
49 };
50 
51 static const struct token t_main[];
52 static const struct token t_show[];
53 static const struct token t_show_iface[];
54 static const struct token t_show_nbr[];
55 static const struct token t_show_mfc[];
56 static const struct token t_show_rib[];
57 static const struct token t_show_fib[];
58 
59 static const struct token t_main[] = {
60 /*	{KEYWORD,	"reload",	RELOAD,		NULL}, */
61 	{KEYWORD,	"show",		SHOW,		t_show},
62 	{ENDTOKEN,	"",		NONE,		NULL}
63 };
64 
65 static const struct token t_show[] = {
66 	{NOTOKEN,	"",		NONE,		NULL},
67 	{KEYWORD,	"igmp",		SHOW_IGMP,	NULL},
68 	{KEYWORD,	"interfaces",	SHOW_IFACE,	t_show_iface},
69 	{KEYWORD,	"mfc",		SHOW_MFC,	t_show_mfc},
70 	{KEYWORD,	"neighbor",	SHOW_NBR,	t_show_nbr},
71 	{KEYWORD,	"rib",		SHOW_RIB,	t_show_rib},
72 	{KEYWORD,	"summary",	SHOW_SUM,	NULL},
73 	{ENDTOKEN,	"",		NONE,		NULL}
74 };
75 
76 static const struct token t_show_iface[] = {
77 	{NOTOKEN,	"",		NONE,		NULL},
78 	{KEYWORD,	"detail",	SHOW_IFACE_DTAIL,NULL},
79 	{IFNAME,	"",		SHOW_IFACE_DTAIL,NULL},
80 	{ENDTOKEN,	"",		NONE,		NULL}
81 };
82 
83 static const struct token t_show_mfc[] = {
84 	{NOTOKEN,	"",		NONE,		NULL},
85 	{KEYWORD,	"detail",	SHOW_MFC_DTAIL,	NULL},
86 	{ENDTOKEN,	"",		NONE,		NULL}
87 };
88 
89 static const struct token t_show_nbr[] = {
90 	{NOTOKEN,	"",		NONE,		NULL},
91 	{KEYWORD,	"detail",	SHOW_NBR_DTAIL,	NULL},
92 	{ENDTOKEN,	"",		NONE,		NULL}
93 };
94 
95 static const struct token t_show_rib[] = {
96 	{NOTOKEN,	"",		NONE,		NULL},
97 	{KEYWORD,	"detail",	SHOW_RIB_DTAIL,	NULL},
98 	{ENDTOKEN,	"",		NONE,		NULL}
99 };
100 
101 static struct parse_result	res;
102 
103 struct parse_result *
104 parse(int argc, char *argv[])
105 {
106 	const struct token	*table = t_main;
107 	const struct token	*match;
108 
109 	bzero(&res, sizeof(res));
110 
111 	while (argc >= 0) {
112 		if ((match = match_token(argv[0], table)) == NULL) {
113 			fprintf(stderr, "valid commands/args:\n");
114 			show_valid_args(table);
115 			return (NULL);
116 		}
117 
118 		argc--;
119 		argv++;
120 
121 		if (match->type == NOTOKEN || match->next == NULL)
122 			break;
123 
124 		table = match->next;
125 	}
126 
127 	if (argc > 0) {
128 		fprintf(stderr, "superfluous argument: %s\n", argv[0]);
129 		return (NULL);
130 	}
131 
132 	return (&res);
133 }
134 
135 const struct token *
136 match_token(const char *word, const struct token table[])
137 {
138 	u_int			 i, match;
139 	const struct token	*t = NULL;
140 
141 	match = 0;
142 
143 	for (i = 0; table[i].type != ENDTOKEN; i++) {
144 		switch (table[i].type) {
145 		case NOTOKEN:
146 			if (word == NULL || strlen(word) == 0) {
147 				match++;
148 				t = &table[i];
149 			}
150 			break;
151 		case KEYWORD:
152 			if (word != NULL && strncmp(word, table[i].keyword,
153 			    strlen(word)) == 0) {
154 				match++;
155 				t = &table[i];
156 				if (t->value)
157 					res.action = t->value;
158 			}
159 			break;
160 		case FLAG:
161 			if (word != NULL && strncmp(word, table[i].keyword,
162 			    strlen(word)) == 0) {
163 				match++;
164 				t = &table[i];
165 				res.flags |= t->value;
166 			}
167 			break;
168 		case ADDRESS:
169 			if (parse_addr(word, &res.addr)) {
170 				match++;
171 				t = &table[i];
172 				if (t->value)
173 					res.action = t->value;
174 			}
175 			break;
176 		case PREFIX:
177 			if (parse_prefix(word, &res.addr, &res.prefixlen)) {
178 				match++;
179 				t = &table[i];
180 				if (t->value)
181 					res.action = t->value;
182 			}
183 			break;
184 		case IFNAME:
185 			if (!match && word != NULL && strlen(word) > 0) {
186 				if (strlcpy(res.ifname, word,
187 				    sizeof(res.ifname)) >=
188 				    sizeof(res.ifname))
189 					err(1, "interface name too long");
190 				match++;
191 				t = &table[i];
192 				if (t->value)
193 					res.action = t->value;
194 			}
195 			break;
196 
197 		case ENDTOKEN:
198 			break;
199 		}
200 	}
201 
202 	if (match != 1) {
203 		if (word == NULL)
204 			fprintf(stderr, "missing argument:\n");
205 		else if (match > 1)
206 			fprintf(stderr, "ambiguous argument: %s\n", word);
207 		else if (match < 1)
208 			fprintf(stderr, "unknown argument: %s\n", word);
209 		return (NULL);
210 	}
211 
212 	return (t);
213 }
214 
215 void
216 show_valid_args(const struct token table[])
217 {
218 	int	i;
219 
220 	for (i = 0; table[i].type != ENDTOKEN; i++) {
221 		switch (table[i].type) {
222 		case NOTOKEN:
223 			fprintf(stderr, "  <cr>\n");
224 			break;
225 		case KEYWORD:
226 		case FLAG:
227 			fprintf(stderr, "  %s\n", table[i].keyword);
228 			break;
229 		case ADDRESS:
230 			fprintf(stderr, "  <address>\n");
231 			break;
232 		case PREFIX:
233 			fprintf(stderr, "  <address>[/<len>]\n");
234 			break;
235 		case IFNAME:
236 			fprintf(stderr, "  <interface>\n");
237 		case ENDTOKEN:
238 			break;
239 		}
240 	}
241 }
242 
243 int
244 parse_addr(const char *word, struct in_addr *addr)
245 {
246 	struct in_addr	ina;
247 
248 	if (word == NULL)
249 		return (0);
250 
251 	bzero(addr, sizeof(struct in_addr));
252 	bzero(&ina, sizeof(ina));
253 
254 	if (inet_pton(AF_INET, word, &ina)) {
255 		addr->s_addr = ina.s_addr;
256 		return (1);
257 	}
258 
259 	return (0);
260 }
261 
262 int
263 parse_prefix(const char *word, struct in_addr *addr, u_int8_t *prefixlen)
264 {
265 	struct in_addr	 ina;
266 	int		 bits = 32;
267 
268 	if (word == NULL)
269 		return (0);
270 
271 	bzero(addr, sizeof(struct in_addr));
272 	bzero(&ina, sizeof(ina));
273 
274 	if (strrchr(word, '/') != NULL) {
275 		if ((bits = inet_net_pton(AF_INET, word,
276 		    &ina, sizeof(ina))) == -1)
277 			return (0);
278 		addr->s_addr = ina.s_addr & htonl(0xffffffff << (32 - bits));
279 		*prefixlen = bits;
280 		return (1);
281 	} else {
282 		*prefixlen = 32;
283 		return (parse_addr(word, addr));
284 	}
285 
286 	return (0);
287 }
288