parser.c revision 1.21 
1/*	$OpenBSD: parser.c,v 1.21 2009/08/17 11:36:01 reyk Exp $	*/
2
3/*
4 * Copyright (c) 2006 Pierre-Yves Ritschard <pyr@openbsd.org>
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 <sys/queue.h>
24
25#include <net/if.h>
26#include <netinet/in.h>
27#include <arpa/inet.h>
28
29#include <err.h>
30#include <errno.h>
31#include <limits.h>
32#include <stdio.h>
33#include <stdlib.h>
34#include <string.h>
35#include <event.h>
36
37#include <openssl/ssl.h>
38
39#include "relayd.h"
40
41#include "parser.h"
42
43enum token_type {
44	NOTOKEN,
45	ENDTOKEN,
46	HOSTID,
47	TABLEID,
48	RDRID,
49	KEYWORD
50};
51
52struct token {
53	enum token_type		 type;
54	const char		*keyword;
55	int			 value;
56	const struct token	*next;
57};
58
59static const struct token t_main[];
60static const struct token t_show[];
61static const struct token t_rdr[];
62static const struct token t_table[];
63static const struct token t_host[];
64static const struct token t_rdr_id[];
65static const struct token t_table_id[];
66static const struct token t_host_id[];
67
68static const struct token t_main[] = {
69	{KEYWORD,	"monitor",	MONITOR,	NULL},
70	{KEYWORD,	"show",		NONE,		t_show},
71	{KEYWORD,	"poll",		POLL,		NULL},
72	{KEYWORD,	"reload",	RELOAD,		NULL},
73	{KEYWORD,	"stop",		SHUTDOWN,	NULL},
74	{KEYWORD,	"redirect",	NONE,		t_rdr},
75	{KEYWORD,	"table",	NONE,		t_table},
76	{KEYWORD,	"host",		NONE,		t_host},
77	{ENDTOKEN,	"",		NONE,		NULL}
78};
79
80static const struct token t_show[] = {
81	{KEYWORD,	"summary",	SHOW_SUM,	NULL},
82	{KEYWORD,	"hosts",	SHOW_HOSTS,	NULL},
83	{KEYWORD,	"redirects",	SHOW_RDRS,	NULL},
84	{KEYWORD,	"relays",	SHOW_RELAYS,	NULL},
85	{KEYWORD,	"routers",	SHOW_ROUTERS,	NULL},
86	{KEYWORD,	"sessions",	SHOW_SESSIONS,	NULL},
87	{ENDTOKEN,	"",		NONE,		NULL}
88};
89
90static const struct token t_rdr[] = {
91	{NOTOKEN,	"",		NONE,		NULL},
92	{KEYWORD,	"disable",	RDR_DISABLE,	t_rdr_id},
93	{KEYWORD,	"enable",	RDR_ENABLE,	t_rdr_id},
94	{ENDTOKEN,	"",		NONE,		NULL}
95};
96
97static const struct token t_table[] = {
98	{NOTOKEN,	"",		NONE,		NULL},
99	{KEYWORD,	"disable",	TABLE_DISABLE,	t_table_id},
100	{KEYWORD,	"enable",	TABLE_ENABLE,	t_table_id},
101	{ENDTOKEN,	"",		NONE,		NULL}
102};
103
104static const struct token t_host[] = {
105	{NOTOKEN,	"",		NONE,		NULL},
106	{KEYWORD,	"disable",	HOST_DISABLE,	t_host_id},
107	{KEYWORD,	"enable",	HOST_ENABLE,	t_host_id},
108	{ENDTOKEN,	"",		NONE,		NULL}
109};
110
111static const struct token t_rdr_id[] = {
112	{RDRID,		"",		NONE,		NULL},
113	{ENDTOKEN,	"",		NONE,		NULL}
114};
115
116static const struct token t_table_id[] = {
117	{TABLEID,	"",		NONE,		NULL},
118	{ENDTOKEN,	"",		NONE,		NULL}
119};
120
121static const struct token t_host_id[] = {
122	{HOSTID,	"",		NONE,		NULL},
123	{ENDTOKEN,	"",		NONE,		NULL}
124};
125
126static struct parse_result	res;
127
128struct parse_result *
129parse(int argc, char *argv[])
130{
131	const struct token	*table = t_main;
132	const struct token	*match;
133
134	bzero(&res, sizeof(res));
135
136	while (argc >= 0) {
137		if ((match = match_token(argv[0], table)) == NULL) {
138			fprintf(stderr, "valid commands/args:\n");
139			show_valid_args(table);
140			return (NULL);
141		}
142
143		argc--;
144		argv++;
145
146		if (match->type == NOTOKEN || match->next == NULL)
147			break;
148
149		table = match->next;
150	}
151
152	if (argc > 0) {
153		fprintf(stderr, "superfluous argument: %s\n", argv[0]);
154		return (NULL);
155	}
156
157	return (&res);
158}
159
160const struct token *
161match_token(const char *word, const struct token table[])
162{
163	u_int			 i, match;
164	const struct token	*t = NULL;
165	const char		*errstr;
166
167	match = 0;
168
169	for (i = 0; table[i].type != ENDTOKEN; i++) {
170		switch (table[i].type) {
171		case NOTOKEN:
172			if (word == NULL || strlen(word) == 0) {
173				match++;
174				t = &table[i];
175			}
176			break;
177		case KEYWORD:
178			if (word != NULL && strncmp(word, table[i].keyword,
179			    strlen(word)) == 0) {
180				match++;
181				t = &table[i];
182				if (t->value)
183					res.action = t->value;
184			}
185			break;
186		case HOSTID:
187			if (word == NULL)
188				break;
189			res.id.id = strtonum(word, 0, UINT_MAX, &errstr);
190			if (errstr) {
191				strlcpy(res.id.name, word, sizeof(res.id.name));
192				res.id.id = EMPTY_ID;
193			}
194			t = &table[i];
195			match++;
196			break;
197		case TABLEID:
198			if (word == NULL)
199				break;
200			res.id.id = strtonum(word, 0, UINT_MAX, &errstr);
201			if (errstr) {
202				strlcpy(res.id.name, word, sizeof(res.id.name));
203				res.id.id = EMPTY_ID;
204			}
205			t = &table[i];
206			match++;
207			break;
208		case RDRID:
209			if (word == NULL)
210				break;
211			res.id.id = strtonum(word, 0, UINT_MAX, &errstr);
212			if (errstr) {
213				strlcpy(res.id.name, word, sizeof(res.id.name));
214				res.id.id = EMPTY_ID;
215			}
216			t = &table[i];
217			match++;
218			break;
219		case ENDTOKEN:
220			break;
221		}
222	}
223
224	if (match != 1) {
225		if (word == NULL)
226			fprintf(stderr, "missing argument:\n");
227		else if (match > 1)
228			fprintf(stderr, "ambiguous argument: %s\n", word);
229		else if (match < 1)
230			fprintf(stderr, "unknown argument: %s\n", word);
231		return (NULL);
232	}
233
234	return (t);
235}
236
237void
238show_valid_args(const struct token table[])
239{
240	int	i;
241
242	for (i = 0; table[i].type != ENDTOKEN; i++) {
243		switch (table[i].type) {
244		case NOTOKEN:
245			fprintf(stderr, "  <cr>\n");
246			break;
247		case KEYWORD:
248			fprintf(stderr, "  %s\n", table[i].keyword);
249			break;
250		case RDRID:
251			fprintf(stderr, "  <redirectid>\n");
252			break;
253		case TABLEID:
254			fprintf(stderr, "  <tableid>\n");
255			break;
256		case HOSTID:
257			fprintf(stderr, "  <hostid>\n");
258			break;
259		case ENDTOKEN:
260			break;
261		}
262	}
263}
264