xref: /openbsd-src/usr.sbin/smtpd/parser.c (revision 43003dfe3ad45d1698bed8a37f2b0f5b14f20d4f)
1 /*	$OpenBSD: parser.c,v 1.8 2009/08/08 00:16:49 gilles 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 #include <sys/tree.h>
25 #include <sys/param.h>
26 
27 #include <net/if.h>
28 #include <netinet/in.h>
29 #include <arpa/inet.h>
30 
31 #include <err.h>
32 #include <errno.h>
33 #include <limits.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <event.h>
38 
39 #include <openssl/ssl.h>
40 
41 #include "smtpd.h"
42 
43 #include "parser.h"
44 
45 enum token_type {
46 	NOTOKEN,
47 	ENDTOKEN,
48 	KEYWORD,
49 	VARIABLE
50 };
51 
52 struct token {
53 	enum token_type		 type;
54 	const char		*keyword;
55 	int			 value;
56 	const struct token	*next;
57 };
58 
59 static const struct token t_main[];
60 static const struct token t_show[];
61 static const struct token t_pause[];
62 static const struct token t_resume[];
63 static const struct token t_schedule[];
64 
65 static const struct token t_main[] = {
66 	{KEYWORD,	"show",		NONE,		t_show},
67 	{KEYWORD,	"monitor",	MONITOR,	NULL},
68 	{KEYWORD,	"pause",	NONE,      	t_pause},
69 	{KEYWORD,	"reload",	RELOAD,		NULL},
70 	{KEYWORD,	"resume",	NONE,      	t_resume},
71 	{KEYWORD,	"stop",		SHUTDOWN,      	NULL},
72 	{KEYWORD,	"schedule",    	SCHEDULE,      	t_schedule},
73 	{ENDTOKEN,	"",		NONE,		NULL}
74 };
75 
76 static const struct token t_show[] = {
77 	{KEYWORD,	"queue",	SHOW_QUEUE,	NULL},
78 	{KEYWORD,	"runqueue",	SHOW_RUNQUEUE,	NULL},
79 	{KEYWORD,	"stats",	SHOW_STATS,	NULL},
80 	{ENDTOKEN,	"",		NONE,		NULL}
81 };
82 
83 static const struct token t_pause[] = {
84 	{KEYWORD,	"local",		PAUSE_MDA,	NULL},
85 	{KEYWORD,	"outgoing",	        PAUSE_MTA,	NULL},
86 	{KEYWORD,	"incoming",	        PAUSE_SMTP,	NULL},
87 	{ENDTOKEN,	"",			NONE,      	NULL}
88 };
89 
90 static const struct token t_resume[] = {
91 	{KEYWORD,	"local",		RESUME_MDA,	NULL},
92 	{KEYWORD,	"outgoing",	        RESUME_MTA,	NULL},
93 	{KEYWORD,	"incoming",	        RESUME_SMTP,	NULL},
94 	{ENDTOKEN,	"",			NONE,      	NULL}
95 };
96 
97 static const struct token t_schedule[] = {
98 	{VARIABLE,	"message id/uid",      	SCHEDULE,	NULL},
99 	{ENDTOKEN,	"",			NONE,      	NULL}
100 };
101 
102 static struct parse_result	res;
103 
104 struct parse_result *
105 parse(int argc, char *argv[])
106 {
107 	const struct token	*table = t_main;
108 	const struct token	*match;
109 
110 	bzero(&res, sizeof(res));
111 
112 	while (argc >= 0) {
113 		if ((match = match_token(argv[0], table)) == NULL) {
114 			fprintf(stderr, "valid commands/args:\n");
115 			show_valid_args(table);
116 			return (NULL);
117 		}
118 
119 		argc--;
120 		argv++;
121 
122 		if (match->type == NOTOKEN || match->next == NULL)
123 			break;
124 
125 		table = match->next;
126 	}
127 
128 	if (argc > 0) {
129 		fprintf(stderr, "superfluous argument: %s\n", argv[0]);
130 		return (NULL);
131 	}
132 
133 	return (&res);
134 }
135 
136 const struct token *
137 match_token(const char *word, const struct token table[])
138 {
139 	u_int			 i, match;
140 	const struct token	*t = NULL;
141 
142 	match = 0;
143 
144 	for (i = 0; table[i].type != ENDTOKEN; i++) {
145 		switch (table[i].type) {
146 		case NOTOKEN:
147 			if (word == NULL || strlen(word) == 0) {
148 				match++;
149 				t = &table[i];
150 			}
151 			break;
152 		case KEYWORD:
153 			if (word != NULL && strncmp(word, table[i].keyword,
154 			    strlen(word)) == 0) {
155 				match++;
156 				t = &table[i];
157 				if (t->value)
158 					res.action = t->value;
159 			}
160 			break;
161 		case VARIABLE:
162 			if (word != NULL && strlen(word) != 0) {
163 				match++;
164 				t = &table[i];
165 				if (t->value) {
166 					res.action = t->value;
167 					res.data = word;
168 				}
169 			}
170 			break;
171 		case ENDTOKEN:
172 			break;
173 		}
174 	}
175 
176 	if (match != 1) {
177 		if (word == NULL)
178 			fprintf(stderr, "missing argument:\n");
179 		else if (match > 1)
180 			fprintf(stderr, "ambiguous argument: %s\n", word);
181 		else if (match < 1)
182 			fprintf(stderr, "unknown argument: %s\n", word);
183 		return (NULL);
184 	}
185 
186 	return (t);
187 }
188 
189 void
190 show_valid_args(const struct token table[])
191 {
192 	int	i;
193 
194 	for (i = 0; table[i].type != ENDTOKEN; i++) {
195 		switch (table[i].type) {
196 		case NOTOKEN:
197 			fprintf(stderr, "  <cr>\n");
198 			break;
199 		case KEYWORD:
200 			fprintf(stderr, "  %s\n", table[i].keyword);
201 			break;
202 		case VARIABLE:
203 			fprintf(stderr, "  %s\n", table[i].keyword);
204 			break;
205 		case ENDTOKEN:
206 			break;
207 		}
208 	}
209 }
210