xref: /illumos-gate/usr/src/lib/libsocket/socket/_soutil.c (revision 711890bc9379ceea66272dc8d4981812224ea86e)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 1989 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
28 /*	  All Rights Reserved   */
29 
30 /*
31  * Portions of this source code were derived from Berkeley 4.3 BSD
32  * under license from the Regents of the University of California.
33  */
34 
35 #pragma ident	"%Z%%M%	%I%	%E% SMI"
36 
37 #include <sys/types.h>
38 #include <sys/socket.h>
39 #include <sys/stat.h>
40 #include <netinet/in.h>
41 #include <errno.h>
42 #include <unistd.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 extern int _stat();
47 
48 /*
49  * XXX The functions in this file are only needed to support transport
50  * providers that have not yet been converted to use /etc/sock2path.
51  * Once all transport providers have been converted this file can be
52  * removed.
53  */
54 
55 static struct netconfig *_s_match_netconf(int family, int type, int proto,
56 		void **nethandle);
57 
58 /*
59  * The following two string arrays map a number as specified
60  * by a user of sockets, to the string as would be returned
61  * by a call to getnetconfig().
62  *
63  * They are used by _s_match_netconf();
64  *
65  * proto_sw contains protocol entries for which there is a corresponding
66  * /dev device. All others would presumably use raw IP and download the
67  * desired protocol.
68  */
69 static char *proto_sw[] = {
70 	"",
71 	"icmp",		/* 1 = ICMP */
72 	"",
73 	"",
74 	"",
75 	"",
76 	"tcp",		/* 6 = TCP */
77 	"",
78 	"",
79 	"",
80 	"",
81 	"",
82 	"",
83 	"",
84 	"",
85 	"",
86 	"",
87 	"udp",		/* 17 = UDP */
88 };
89 
90 static char *family_sw[] = {
91 	"-",		/* 0 = AF_UNSPEC */
92 	"loopback",	/* 1 = AF_UNIX */
93 	"inet",		/* 2 = AF_INET */
94 	"implink",	/* 3 = AF_IMPLINK */
95 	"pup",		/* 4 = AF_PUP */
96 	"chaos",	/* 5 = AF_CHAOS */
97 	"ns",		/* 6 = AF_NS */
98 	"nbs",		/* 7 = AF_NBS */
99 	"ecma",		/* 8 = AF_ECMA */
100 	"datakit",	/* 9 = AF_DATAKIT */
101 	"ccitt",	/* 10 = AF_CCITT */
102 	"sna",		/* 11 = AF_SNA */
103 	"decnet",	/* 12 = AF_DECnet */
104 	"dli",		/* 13 = AF_DLI */
105 	"lat",		/* 14 = AF_LAT */
106 	"hylink",	/* 15 = AF_HYLINK */
107 	"appletalk",	/* 16 = AF_APPLETALK */
108 	"nit",		/* 17 = AF_NIT */
109 	"ieee802",	/* 18 = AF_802 */
110 	"osi",		/* 19 = AF_OSI */
111 	"x25",		/* 20 = AF_X25 */
112 	"osinet",	/* 21 = AF_OSINET */
113 	"gosip",	/* 22 = AF_GOSIP */
114 	"ipx",		/* 23 = AF_IPX */
115 	"route",	/* 24 = AF_ROUTE */
116 	"link",		/* 25 = AF_LINK */
117 	"inet6",	/* 26 = AF_INET6 */
118 	"key",		/* 27 = AF_KEY */
119 };
120 
121 /*
122  * Lookup family/type/protocol in /etc/netconfig.
123  * Returns the pathname and a prototype value (to be passed into SO_PROTOTYPE)
124  * The path is malloc'ed and has to be freed by the caller.
125  */
126 int
127 _s_netconfig_path(int family, int type, int protocol,
128 	char **pathp, int *prototype)
129 {
130 	struct netconfig	*net;
131 	void				*nethandle;
132 	struct stat			stats;
133 
134 	net = _s_match_netconf(family, type, protocol, &nethandle);
135 	if (net == NULL)
136 		return (-1);
137 
138 	if (strcmp(net->nc_proto, NC_NOPROTO) != 0)
139 		*prototype = 0;
140 	else
141 		*prototype = protocol;
142 
143 retry:
144 #if defined(i386)
145 	if (_xstat(_STAT_VER, net->nc_device, &stats) < 0) {
146 #else
147 	if (_stat(net->nc_device, &stats) < 0) {
148 #endif
149 		switch (errno) {
150 		case EINTR:
151 			goto retry;
152 
153 		case ENOENT:
154 		case ENOLINK:
155 		case ELOOP:
156 		case EMULTIHOP:
157 		case ENOTDIR:
158 			errno = EPFNOSUPPORT;
159 			break;
160 		}
161 		endnetconfig(nethandle); /* finished with netconfig struct */
162 		return (-1);
163 	}
164 	if (!S_ISCHR(stats.st_mode)) {
165 		errno = EPFNOSUPPORT;
166 		endnetconfig(nethandle); /* finished with netconfig struct */
167 		return (-1);
168 	}
169 	*pathp = malloc(strlen(net->nc_device) + 1);
170 	if (*pathp == NULL) {
171 		endnetconfig(nethandle);
172 		errno = ENOMEM;
173 		return (-1);
174 	}
175 	(void) strcpy(*pathp, net->nc_device);
176 	endnetconfig(nethandle); /* finished with netconfig struct */
177 	return (0);
178 }
179 
180 /*
181  * Match config entry for protocol
182  * requested.
183  */
184 static struct netconfig *
185 _s_match_netconf(int family, int type, int proto, void **nethandle)
186 {
187 	struct netconfig	*net;
188 	struct netconfig	*maybe;
189 	char			*oproto;
190 
191 	if (family < 0 ||
192 		family >= (int)sizeof (family_sw) / (int)sizeof (char *) ||
193 		proto < 0 || proto >= IPPROTO_MAX)  {
194 			errno = EPROTONOSUPPORT;
195 			return (NULL);
196 	}
197 	if (proto) {
198 		if (proto >= (int)sizeof (proto_sw) / (int)sizeof (char *))
199 			oproto = "";
200 		else	oproto = proto_sw[proto];
201 	}
202 
203 	/*
204 	 * Loop through each entry in netconfig
205 	 * until one matches or we reach the end.
206 	 */
207 	if ((*nethandle = setnetconfig()) == NULL) {
208 		return (NULL);
209 	}
210 
211 	maybe = NULL;
212 	while ((net = getnetconfig(*nethandle)) != NULL) {
213 		/*
214 		 * We make a copy of net->nc_semantics rather than modifying
215 		 * it in place because the network selection code shares the
216 		 * structures returned by getnetconfig() among all its callers.
217 		 * See bug #1160886 for more details.
218 		 */
219 		unsigned int semantics = net->nc_semantics;
220 
221 		if (semantics == NC_TPI_COTS_ORD)
222 			semantics = NC_TPI_COTS;
223 		if (proto) {
224 			if (strcmp(net->nc_protofmly, family_sw[family]) == 0 &&
225 			    semantics == type &&
226 			    strcmp(net->nc_proto, oproto) == 0)
227 				break;
228 
229 			if (strcmp(net->nc_protofmly, family_sw[family]) == 0 &&
230 			    type == SOCK_RAW &&
231 			    semantics == SOCK_RAW &&
232 			    strcmp(net->nc_proto, NC_NOPROTO) == 0 &&
233 			    maybe == NULL)
234 				maybe = net;	/* in case no exact match */
235 
236 			continue;
237 		} else	{
238 			if (strcmp(net->nc_protofmly, family_sw[family]) == 0 &&
239 					semantics == type) {
240 				break;
241 			}
242 		}
243 	}
244 	if (net == NULL && maybe)
245 		net = maybe;
246 
247 	if (net == NULL) {
248 		endnetconfig(*nethandle);
249 		errno = EPROTONOSUPPORT;
250 		return (NULL);
251 	}
252 
253 	return (net);
254 }
255