xref: /freebsd/lib/libc/net/getservent.c (revision 8e537d168674d6b65869f73c20813001af875738)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char sccsid[] = "@(#)getservent.c	8.1 (Berkeley) 6/4/93";
36 #endif /* LIBC_SCCS and not lint */
37 
38 #include <sys/types.h>
39 #include <sys/socket.h>
40 #include <netdb.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <stdlib.h>
44 #ifdef YP
45 #include <rpc/rpc.h>
46 #include <rpcsvc/yp_prot.h>
47 #include <rpcsvc/ypclnt.h>
48 static int serv_stepping_yp = 0;
49 #endif
50 
51 extern int _yp_check __P(( char ** ));
52 
53 #define	MAXALIASES	35
54 
55 static FILE *servf = NULL;
56 static char line[BUFSIZ+1];
57 static struct servent serv;
58 static char *serv_aliases[MAXALIASES];
59 int _serv_stayopen;
60 
61 #ifdef YP
62 char *___getservbyname_yp = NULL;
63 char *___getservbyproto_yp = NULL;
64 int ___getservbyport_yp = 0;
65 static char *yp_domain = NULL;
66 
67 static int
68 _getservbyport_yp(line)
69 	char *line;
70 {
71 	char *result;
72 	int resultlen;
73 	char buf[YPMAXRECORD];
74 	int rv;
75 
76 	snprintf(buf, sizeof(buf), "%d/%s", ntohs(___getservbyport_yp),
77 						___getservbyproto_yp);
78 
79 	___getservbyport_yp = 0;
80 	___getservbyproto_yp = NULL;
81 
82 	if(!yp_domain) {
83 		if(yp_get_default_domain(&yp_domain))
84 			return (0);
85 	}
86 
87 	/*
88 	 * We have to be a little flexible here. Ideally you're supposed
89 	 * to have both a services.byname and a services.byport map, but
90 	 * some systems have only services.byname. FreeBSD cheats a little
91 	 * by putting the services.byport information in the same map as
92 	 * services.byname so that either case will work. We allow for both
93 	 * possibilities here: if there is no services.byport map, we try
94 	 * services.byname instead.
95 	 */
96 	if ((rv = yp_match(yp_domain, "services.byport", buf, strlen(buf),
97 						&result, &resultlen))) {
98 		if (rv == YPERR_MAP) {
99 			if (yp_match(yp_domain, "services.byname", buf,
100 					strlen(buf), &result, &resultlen))
101 			return(0);
102 		} else
103 			return(0);
104 	}
105 
106 	/* getservent() expects lines terminated with \n -- make it happy */
107 	snprintf(line, BUFSIZ, "%.*s\n", resultlen, result);
108 
109 	free(result);
110 	return(1);
111 }
112 
113 static int
114 _getservbyname_yp(line)
115 	char *line;
116 {
117 	char *result;
118 	int resultlen;
119 	char buf[YPMAXRECORD];
120 
121 	if(!yp_domain) {
122 		if(yp_get_default_domain(&yp_domain))
123 			return (0);
124 	}
125 
126 	snprintf(buf, sizeof(buf), "%s/%s", ___getservbyname_yp,
127 						___getservbyproto_yp);
128 
129 	___getservbyname_yp = 0;
130 	___getservbyproto_yp = NULL;
131 
132 	if (yp_match(yp_domain, "services.byname", buf, strlen(buf),
133 						&result, &resultlen)) {
134 		return(0);
135 	}
136 
137 	/* getservent() expects lines terminated with \n -- make it happy */
138 	snprintf(line, BUFSIZ, "%.*s\n", resultlen, result);
139 
140 	free(result);
141 	return(1);
142 }
143 
144 static int
145 _getservent_yp(line)
146 	char *line;
147 {
148 	static char *key = NULL;
149 	static int keylen;
150 	char *lastkey, *result;
151 	int resultlen;
152 	int rv;
153 
154 	if(!yp_domain) {
155 		if(yp_get_default_domain(&yp_domain))
156 			return (0);
157 	}
158 
159 	if (!serv_stepping_yp) {
160 		if (key)
161 			free(key);
162 		if ((rv = yp_first(yp_domain, "services.byname", &key, &keylen,
163 			     &result, &resultlen))) {
164 			serv_stepping_yp = 0;
165 			return(0);
166 		}
167 		serv_stepping_yp = 1;
168 	} else {
169 		lastkey = key;
170 		rv = yp_next(yp_domain, "services.byname", key, keylen, &key,
171 			     &keylen, &result, &resultlen);
172 		free(lastkey);
173 		if (rv) {
174 			serv_stepping_yp = 0;
175 			return (0);
176 		}
177 	}
178 
179 	/* getservent() expects lines terminated with \n -- make it happy */
180 	snprintf(line, BUFSIZ, "%.*s\n", resultlen, result);
181 
182 	free(result);
183 
184 	return(1);
185 }
186 #endif
187 
188 void
189 setservent(f)
190 	int f;
191 {
192 	if (servf == NULL)
193 		servf = fopen(_PATH_SERVICES, "r" );
194 	else
195 		rewind(servf);
196 	_serv_stayopen |= f;
197 }
198 
199 void
200 endservent()
201 {
202 	if (servf) {
203 		fclose(servf);
204 		servf = NULL;
205 	}
206 	_serv_stayopen = 0;
207 }
208 
209 struct servent *
210 getservent()
211 {
212 	char *p;
213 	register char *cp, **q;
214 
215 #ifdef YP
216 	if (serv_stepping_yp && _getservent_yp(line)) {
217 		p = (char *)&line;
218 		goto unpack;
219 	}
220 tryagain:
221 #endif
222 	if (servf == NULL && (servf = fopen(_PATH_SERVICES, "r" )) == NULL)
223 		return (NULL);
224 again:
225 	if ((p = fgets(line, BUFSIZ, servf)) == NULL)
226 		return (NULL);
227 #ifdef YP
228 	if (*p == '+' && _yp_check(NULL)) {
229 		if (___getservbyname_yp != NULL) {
230 			if (!_getservbyname_yp(&line))
231 				goto tryagain;
232 		}
233 		else if (___getservbyport_yp != 0) {
234 			if (!_getservbyport_yp(&line))
235 				goto tryagain;
236 		}
237 		else if (!_getservent_yp(&line))
238 			goto tryagain;
239 	}
240 unpack:
241 #endif
242 	if (*p == '#')
243 		goto again;
244 	cp = strpbrk(p, "#\n");
245 	if (cp == NULL)
246 		goto again;
247 	*cp = '\0';
248 	serv.s_name = p;
249 	p = strpbrk(p, " \t");
250 	if (p == NULL)
251 		goto again;
252 	*p++ = '\0';
253 	while (*p == ' ' || *p == '\t')
254 		p++;
255 	cp = strpbrk(p, ",/");
256 	if (cp == NULL)
257 		goto again;
258 	*cp++ = '\0';
259 	serv.s_port = htons((u_short)atoi(p));
260 	serv.s_proto = cp;
261 	q = serv.s_aliases = serv_aliases;
262 	cp = strpbrk(cp, " \t");
263 	if (cp != NULL)
264 		*cp++ = '\0';
265 	while (cp && *cp) {
266 		if (*cp == ' ' || *cp == '\t') {
267 			cp++;
268 			continue;
269 		}
270 		if (q < &serv_aliases[MAXALIASES - 1])
271 			*q++ = cp;
272 		cp = strpbrk(cp, " \t");
273 		if (cp != NULL)
274 			*cp++ = '\0';
275 	}
276 	*q = NULL;
277 	return (&serv);
278 }
279