xref: /openbsd/usr.sbin/dvmrpctl/parser.c (revision 09467b48) 
1 /*	$OpenBSD: parser.c,v 1.6 2017/07/28 13:03:23 florian 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_log[];
58 
59 static const struct token t_main[] = {
60 /*	{KEYWORD,	"reload",	RELOAD,		NULL}, */
61 	{KEYWORD,	"show",		SHOW,		t_show},
62 	{KEYWORD,	"log",		NONE,		t_log},
63 	{ENDTOKEN,	"",		NONE,		NULL}
64 };
65 
66 static const struct token t_show[] = {
67 	{NOTOKEN,	"",		NONE,		NULL},
68 	{KEYWORD,	"igmp",		SHOW_IGMP,	NULL},
69 	{KEYWORD,	"interfaces",	SHOW_IFACE,	t_show_iface},
70 	{KEYWORD,	"mfc",		SHOW_MFC,	t_show_mfc},
71 	{KEYWORD,	"neighbor",	SHOW_NBR,	t_show_nbr},
72 	{KEYWORD,	"rib",		SHOW_RIB,	t_show_rib},
73 	{KEYWORD,	"summary",	SHOW_SUM,	NULL},
74 	{ENDTOKEN,	"",		NONE,		NULL}
75 };
76 
77 static const struct token t_show_iface[] = {
78 	{NOTOKEN,	"",		NONE,		NULL},
79 	{KEYWORD,	"detail",	SHOW_IFACE_DTAIL,NULL},
80 	{IFNAME,	"",		SHOW_IFACE_DTAIL,NULL},
81 	{ENDTOKEN,	"",		NONE,		NULL}
82 };
83 
84 static const struct token t_show_mfc[] = {
85 	{NOTOKEN,	"",		NONE,		NULL},
86 	{KEYWORD,	"detail",	SHOW_MFC_DTAIL,	NULL},
87 	{ENDTOKEN,	"",		NONE,		NULL}
88 };
89 
90 static const struct token t_show_nbr[] = {
91 	{NOTOKEN,	"",		NONE,		NULL},
92 	{KEYWORD,	"detail",	SHOW_NBR_DTAIL,	NULL},
93 	{ENDTOKEN,	"",		NONE,		NULL}
94 };
95 
96 static const struct token t_show_rib[] = {
97 	{NOTOKEN,	"",		NONE,		NULL},
98 	{KEYWORD,	"detail",	SHOW_RIB_DTAIL,	NULL},
99 	{ENDTOKEN,	"",		NONE,		NULL}
100 };
101 
102 static const struct token t_log[] = {
103 	{KEYWORD,	"verbose",	LOG_VERBOSE,	NULL},
104 	{KEYWORD,	"brief",	LOG_BRIEF,	NULL},
105 	{ENDTOKEN,	"",		NONE,		NULL}
106 };
107 
108 
109 static void show_valid_args(const struct token *);
110 static const struct token *match_token(const char *, const struct token *,
111     struct parse_result *);
112 
113 struct parse_result *
114 parse(int argc, char *argv[])
115 {
116 	static struct parse_result	res;
117 	const struct token	*table = t_main;
118 	const struct token	*match;
119 
120 	bzero(&res, sizeof(res));
121 
122 	while (argc >= 0) {
123 		if ((match = match_token(argv[0], table, &res)) == NULL) {
124 			fprintf(stderr, "valid commands/args:\n");
125 			show_valid_args(table);
126 			return (NULL);
127 		}
128 
129 		argc--;
130 		argv++;
131 
132 		if (match->type == NOTOKEN || match->next == NULL)
133 			break;
134 
135 		table = match->next;
136 	}
137 
138 	if (argc > 0) {
139 		fprintf(stderr, "superfluous argument: %s\n", argv[0]);
140 		return (NULL);
141 	}
142 
143 	return (&res);
144 }
145 
146 static const struct token *
147 match_token(const char *word, const struct token *table,
148     struct parse_result *res)
149 {
150 	u_int			 i, match;
151 	const struct token	*t = NULL;
152 
153 	match = 0;
154 
155 	for (i = 0; table[i].type != ENDTOKEN; i++) {
156 		switch (table[i].type) {
157 		case NOTOKEN:
158 			if (word == NULL || strlen(word) == 0) {
159 				match++;
160 				t = &table[i];
161 			}
162 			break;
163 		case KEYWORD:
164 			if (word != NULL && strncmp(word, table[i].keyword,
165 			    strlen(word)) == 0) {
166 				match++;
167 				t = &table[i];
168 				if (t->value)
169 					res->action = t->value;
170 			}
171 			break;
172 		case FLAG:
173 			if (word != NULL && strncmp(word, table[i].keyword,
174 			    strlen(word)) == 0) {
175 				match++;
176 				t = &table[i];
177 				res->flags |= t->value;
178 			}
179 			break;
180 		case ADDRESS:
181 			if (parse_addr(word, &res->addr)) {
182 				match++;
183 				t = &table[i];
184 				if (t->value)
185 					res->action = t->value;
186 			}
187 			break;
188 		case PREFIX:
189 			if (parse_prefix(word, &res->addr, &res->prefixlen)) {
190 				match++;
191 				t = &table[i];
192 				if (t->value)
193 					res->action = t->value;
194 			}
195 			break;
196 		case IFNAME:
197 			if (!match && word != NULL && strlen(word) > 0) {
198 				if (strlcpy(res->ifname, word,
199 				    sizeof(res->ifname)) >=
200 				    sizeof(res->ifname))
201 					err(1, "interface name too long");
202 				match++;
203 				t = &table[i];
204 				if (t->value)
205 					res->action = t->value;
206 			}
207 			break;
208 
209 		case ENDTOKEN:
210 			break;
211 		}
212 	}
213 
214 	if (match != 1) {
215 		if (word == NULL)
216 			fprintf(stderr, "missing argument:\n");
217 		else if (match > 1)
218 			fprintf(stderr, "ambiguous argument: %s\n", word);
219 		else if (match < 1)
220 			fprintf(stderr, "unknown argument: %s\n", word);
221 		return (NULL);
222 	}
223 
224 	return (t);
225 }
226 
227 static void
228 show_valid_args(const struct token *table)
229 {
230 	int	i;
231 
232 	for (i = 0; table[i].type != ENDTOKEN; i++) {
233 		switch (table[i].type) {
234 		case NOTOKEN:
235 			fprintf(stderr, "  <cr>\n");
236 			break;
237 		case KEYWORD:
238 		case FLAG:
239 			fprintf(stderr, "  %s\n", table[i].keyword);
240 			break;
241 		case ADDRESS:
242 			fprintf(stderr, "  <address>\n");
243 			break;
244 		case PREFIX:
245 			fprintf(stderr, "  <address>[/<len>]\n");
246 			break;
247 		case IFNAME:
248 			fprintf(stderr, "  <interface>\n");
249 		case ENDTOKEN:
250 			break;
251 		}
252 	}
253 }
254 
255 int
256 parse_addr(const char *word, struct in_addr *addr)
257 {
258 	struct in_addr	ina;
259 
260 	if (word == NULL)
261 		return (0);
262 
263 	bzero(addr, sizeof(struct in_addr));
264 	bzero(&ina, sizeof(ina));
265 
266 	if (inet_pton(AF_INET, word, &ina)) {
267 		addr->s_addr = ina.s_addr;
268 		return (1);
269 	}
270 
271 	return (0);
272 }
273 
274 int
275 parse_prefix(const char *word, struct in_addr *addr, u_int8_t *prefixlen)
276 {
277 	struct in_addr	 ina;
278 	int		 bits = 32;
279 
280 	if (word == NULL)
281 		return (0);
282 
283 	bzero(addr, sizeof(struct in_addr));
284 	bzero(&ina, sizeof(ina));
285 
286 	if (strrchr(word, '/') != NULL) {
287 		if ((bits = inet_net_pton(AF_INET, word,
288 		    &ina, sizeof(ina))) == -1)
289 			return (0);
290 		addr->s_addr = ina.s_addr & htonl(0xffffffff << (32 - bits));
291 		*prefixlen = bits;
292 		return (1);
293 	} else {
294 		*prefixlen = 32;
295 		return (parse_addr(word, addr));
296 	}
297 
298 	return (0);
299 }
300