xref: /freebsd/lib/libc/net/getproto.c (revision 1db64f89363c97858961c4df0b7d02f3223723cf)
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 #include <errno.h>
33 #include <netdb.h>
34 #include <nsswitch.h>
35 #include "netdb_private.h"
36 #ifdef NS_CACHING
37 #include "nscache.h"
38 #endif
39 #include "nss_tls.h"
40 
41 static const ns_src defaultsrc[] = {
42 	{ NSSRC_FILES, NS_SUCCESS },
43 	{ NULL, 0 }
44 };
45 
46 static int
47 files_getprotobynumber(void *retval, void *mdata, va_list ap)
48 {
49 	struct protoent pe;
50 	struct protoent_data *ped;
51 	int error;
52 
53 	int number;
54 	struct protoent	*pptr;
55 	char *buffer;
56 	size_t buflen;
57 	int *errnop;
58 
59 	number = va_arg(ap, int);
60 	pptr = va_arg(ap, struct protoent *);
61 	buffer = va_arg(ap, char *);
62 	buflen = va_arg(ap, size_t);
63 	errnop = va_arg(ap, int *);
64 
65 	if ((ped = __protoent_data_init()) == NULL) {
66 		*errnop = errno;
67 		return (NS_NOTFOUND);
68 	}
69 
70 	__setprotoent_p(ped->stayopen, ped);
71 	while ((error = __getprotoent_p(&pe, ped)) == 0)
72 		if (pe.p_proto == number)
73 			break;
74 	if (!ped->stayopen)
75 		__endprotoent_p(ped);
76 	if (error != 0) {
77 		*errnop = errno;
78 		return (NS_NOTFOUND);
79 	}
80 	if (__copy_protoent(&pe, pptr, buffer, buflen) != 0) {
81 		*errnop = errno;
82 		return (NS_RETURN);
83 	}
84 
85 	*((struct protoent **)retval) = pptr;
86 	return (NS_SUCCESS);
87 }
88 
89 int
90 getprotobynumber_r(int proto, struct protoent *pptr, char *buffer,
91     size_t buflen, struct protoent **result)
92 {
93 #ifdef NS_CACHING
94 	static const nss_cache_info cache_info =
95     		NS_COMMON_CACHE_INFO_INITIALIZER(
96 		protocols, (void *)nss_lt_id,
97 		__proto_id_func, __proto_marshal_func, __proto_unmarshal_func);
98 #endif
99 
100 	static const ns_dtab dtab[] = {
101 		{ NSSRC_FILES, files_getprotobynumber, NULL },
102 #ifdef NS_CACHING
103 		NS_CACHE_CB(&cache_info)
104 #endif
105 		{ NULL, NULL, NULL }
106 	};
107 	int	rv, ret_errno;
108 
109 	ret_errno = 0;
110 	*result = NULL;
111 	rv = nsdispatch(result, dtab, NSDB_PROTOCOLS, "getprotobynumber_r",
112 		defaultsrc, proto, pptr, buffer, buflen, &ret_errno);
113 
114 	if (rv != NS_SUCCESS) {
115 		errno = ret_errno;
116 		return (ret_errno);
117 	}
118 	return (0);
119 }
120 
121 struct protoent *
122 getprotobynumber(int proto)
123 {
124 	struct protodata *pd;
125 	struct protoent *rval;
126 
127 	if ((pd = __protodata_init()) == NULL)
128 		return (NULL);
129 	if (getprotobynumber_r(proto, &pd->proto, pd->data, sizeof(pd->data),
130 	    &rval) != 0)
131 		return (NULL);
132 	return (rval);
133 }
134