xref: /freebsd/lib/libc/net/getproto.c (revision 4f52dfbb)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if defined(LIBC_SCCS) && !defined(lint)
33 static char sccsid[] = "@(#)getproto.c	8.1 (Berkeley) 6/4/93";
34 #endif /* LIBC_SCCS and not lint */
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <errno.h>
39 #include <netdb.h>
40 #include <nsswitch.h>
41 #include "netdb_private.h"
42 #ifdef NS_CACHING
43 #include "nscache.h"
44 #endif
45 #include "nss_tls.h"
46 
47 static const ns_src defaultsrc[] = {
48 	{ NSSRC_FILES, NS_SUCCESS },
49 	{ NULL, 0 }
50 };
51 
52 static int
53 files_getprotobynumber(void *retval, void *mdata, va_list ap)
54 {
55 	struct protoent pe;
56 	struct protoent_data *ped;
57 	int error;
58 
59 	int number;
60 	struct protoent	*pptr;
61 	char *buffer;
62 	size_t buflen;
63 	int *errnop;
64 
65 	number = va_arg(ap, int);
66 	pptr = va_arg(ap, struct protoent *);
67 	buffer = va_arg(ap, char *);
68 	buflen = va_arg(ap, size_t);
69 	errnop = va_arg(ap, int *);
70 
71 	if ((ped = __protoent_data_init()) == NULL) {
72 		*errnop = errno;
73 		return (NS_NOTFOUND);
74 	}
75 
76 	__setprotoent_p(ped->stayopen, ped);
77 	while ((error = __getprotoent_p(&pe, ped)) == 0)
78 		if (pe.p_proto == number)
79 			break;
80 	if (!ped->stayopen)
81 		__endprotoent_p(ped);
82 	if (error != 0) {
83 		*errnop = errno;
84 		return (NS_NOTFOUND);
85 	}
86 	if (__copy_protoent(&pe, pptr, buffer, buflen) != 0) {
87 		*errnop = errno;
88 		return (NS_RETURN);
89 	}
90 
91 	*((struct protoent **)retval) = pptr;
92 	return (NS_SUCCESS);
93 }
94 
95 int
96 getprotobynumber_r(int proto, struct protoent *pptr, char *buffer,
97     size_t buflen, struct protoent **result)
98 {
99 #ifdef NS_CACHING
100 	static const nss_cache_info cache_info =
101     		NS_COMMON_CACHE_INFO_INITIALIZER(
102 		protocols, (void *)nss_lt_id,
103 		__proto_id_func, __proto_marshal_func, __proto_unmarshal_func);
104 #endif
105 
106 	static const ns_dtab dtab[] = {
107 		{ NSSRC_FILES, files_getprotobynumber, NULL },
108 #ifdef NS_CACHING
109 		NS_CACHE_CB(&cache_info)
110 #endif
111 		{ NULL, NULL, NULL }
112 	};
113 	int	rv, ret_errno;
114 
115 	ret_errno = 0;
116 	*result = NULL;
117 	rv = nsdispatch(result, dtab, NSDB_PROTOCOLS, "getprotobynumber_r",
118 		defaultsrc, proto, pptr, buffer, buflen, &ret_errno);
119 
120 	if (rv != NS_SUCCESS) {
121 		errno = ret_errno;
122 		return (ret_errno);
123 	}
124 	return (0);
125 }
126 
127 struct protoent *
128 getprotobynumber(int proto)
129 {
130 	struct protodata *pd;
131 	struct protoent *rval;
132 
133 	if ((pd = __protodata_init()) == NULL)
134 		return (NULL);
135 	if (getprotobynumber_r(proto, &pd->proto, pd->data, sizeof(pd->data),
136 	    &rval) != 0)
137 		return (NULL);
138 	return (rval);
139 }
140