1/*	$OpenBSD: getservent.c,v 1.15 2015/09/14 07:38:38 guenther Exp $ */
2/*
3 * Copyright (c) 1983, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 *    may be used to endorse or promote products derived from this software
16 *    without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31#include <sys/types.h>
32#include <sys/socket.h>
33
34#include <errno.h>
35#include <limits.h>
36#include <netdb.h>
37#include <stdio.h>
38#include <string.h>
39#include <stdlib.h>
40
41void
42setservent_r(int f, struct servent_data *sd)
43{
44	if (sd->fp == NULL)
45		sd->fp = fopen(_PATH_SERVICES, "re" );
46	else
47		rewind(sd->fp);
48	sd->stayopen |= f;
49}
50DEF_WEAK(setservent_r);
51
52void
53endservent_r(struct servent_data *sd)
54{
55	if (sd->fp) {
56		fclose(sd->fp);
57		sd->fp = NULL;
58	}
59	free(sd->aliases);
60	sd->aliases = NULL;
61	sd->maxaliases = 0;
62	free(sd->line);
63	sd->line = NULL;
64	sd->stayopen = 0;
65}
66DEF_WEAK(endservent_r);
67
68int
69getservent_r(struct servent *se, struct servent_data *sd)
70{
71	char *p, *cp, **q, *endp;
72	size_t len;
73	long l;
74	int serrno;
75
76	if (sd->fp == NULL && (sd->fp = fopen(_PATH_SERVICES, "re" )) == NULL)
77		return (-1);
78again:
79	if ((p = fgetln(sd->fp, &len)) == NULL)
80		return (-1);
81	if (len == 0 || *p == '#' || *p == '\n')
82		goto again;
83	if (p[len-1] == '\n')
84		len--;
85	if ((cp = memchr(p, '#', len)) != NULL)
86		len = cp - p;
87	cp = realloc(sd->line, len + 1);
88	if (cp == NULL)
89		return (-1);
90	sd->line = se->s_name = memcpy(cp, p, len);
91	cp[len] = '\0';
92	p = strpbrk(cp, " \t");
93	if (p == NULL)
94		goto again;
95	*p++ = '\0';
96	while (*p == ' ' || *p == '\t')
97		p++;
98	cp = strpbrk(p, ",/");
99	if (cp == NULL)
100		goto again;
101	*cp++ = '\0';
102	l = strtol(p, &endp, 10);
103	if (endp == p || *endp != '\0' || l < 0 || l > USHRT_MAX)
104		goto again;
105	se->s_port = htons((in_port_t)l);
106	se->s_proto = cp;
107	if (sd->aliases == NULL) {
108		sd->maxaliases = 10;
109		sd->aliases = calloc(sd->maxaliases, sizeof(char *));
110		if (sd->aliases == NULL) {
111			serrno = errno;
112			endservent_r(sd);
113			errno = serrno;
114			return (-1);
115		}
116	}
117	q = se->s_aliases = sd->aliases;
118	cp = strpbrk(cp, " \t");
119	if (cp != NULL)
120		*cp++ = '\0';
121	while (cp && *cp) {
122		if (*cp == ' ' || *cp == '\t') {
123			cp++;
124			continue;
125		}
126		if (q == &se->s_aliases[sd->maxaliases - 1]) {
127			p = reallocarray(se->s_aliases, sd->maxaliases,
128			    2 * sizeof(char *));
129			if (p == NULL) {
130				serrno = errno;
131				endservent_r(sd);
132				errno = serrno;
133				return (-1);
134			}
135			sd->maxaliases *= 2;
136			q = (char **)p + (q - se->s_aliases);
137			se->s_aliases = sd->aliases = (char **)p;
138		}
139		*q++ = cp;
140		cp = strpbrk(cp, " \t");
141		if (cp != NULL)
142			*cp++ = '\0';
143	}
144	*q = NULL;
145	return (0);
146}
147DEF_WEAK(getservent_r);
148
149struct servent_data _servent_data;	/* shared with getservby{name,port}.c */
150
151void
152setservent(int f)
153{
154	setservent_r(f, &_servent_data);
155}
156
157void
158endservent(void)
159{
160	endservent_r(&_servent_data);
161}
162
163struct servent *
164getservent(void)
165{
166	static struct servent serv;
167
168	if (getservent_r(&serv, &_servent_data) != 0)
169		return (NULL);
170	return (&serv);
171}
172