xref: /illumos-gate/usr/src/lib/libsocket/socket/_soutil.c (revision fb2a9bae0030340ad72b9c26ba1ffee2ee3cafec)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2010 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 #include <sys/types.h>
36 #include <sys/socket.h>
37 #include <sys/stat.h>
38 #include <netinet/in.h>
39 #include <errno.h>
40 #include <unistd.h>
41 #include <stdlib.h>
42 #include <string.h>
43 
44 /*
45  * XXX The functions in this file are only needed to support transport
46  * providers that have not yet been converted to use /etc/sock2path.
47  * Once all transport providers have been converted this file can be
48  * removed.
49  */
50 
51 static struct netconfig *_s_match_netconf(int family, int type, int proto,
52 		void **nethandle);
53 
54 /*
55  * The following two string arrays map a number as specified
56  * by a user of sockets, to the string as would be returned
57  * by a call to getnetconfig().
58  *
59  * They are used by _s_match_netconf();
60  *
61  * proto_sw contains protocol entries for which there is a corresponding
62  * /dev device. All others would presumably use raw IP and download the
63  * desired protocol.
64  */
65 static char *proto_sw[] = {
66 	"",
67 	"icmp",		/* 1 = ICMP */
68 	"",
69 	"",
70 	"",
71 	"",
72 	"tcp",		/* 6 = TCP */
73 	"",
74 	"",
75 	"",
76 	"",
77 	"",
78 	"",
79 	"",
80 	"",
81 	"",
82 	"",
83 	"udp",		/* 17 = UDP */
84 };
85 
86 static char *family_sw[] = {
87 	"-",		/* 0 = AF_UNSPEC */
88 	"loopback",	/* 1 = AF_UNIX */
89 	"inet",		/* 2 = AF_INET */
90 	"implink",	/* 3 = AF_IMPLINK */
91 	"pup",		/* 4 = AF_PUP */
92 	"chaos",	/* 5 = AF_CHAOS */
93 	"ns",		/* 6 = AF_NS */
94 	"nbs",		/* 7 = AF_NBS */
95 	"ecma",		/* 8 = AF_ECMA */
96 	"datakit",	/* 9 = AF_DATAKIT */
97 	"ccitt",	/* 10 = AF_CCITT */
98 	"sna",		/* 11 = AF_SNA */
99 	"decnet",	/* 12 = AF_DECnet */
100 	"dli",		/* 13 = AF_DLI */
101 	"lat",		/* 14 = AF_LAT */
102 	"hylink",	/* 15 = AF_HYLINK */
103 	"appletalk",	/* 16 = AF_APPLETALK */
104 	"nit",		/* 17 = AF_NIT */
105 	"ieee802",	/* 18 = AF_802 */
106 	"osi",		/* 19 = AF_OSI */
107 	"x25",		/* 20 = AF_X25 */
108 	"osinet",	/* 21 = AF_OSINET */
109 	"gosip",	/* 22 = AF_GOSIP */
110 	"ipx",		/* 23 = AF_IPX */
111 	"route",	/* 24 = AF_ROUTE */
112 	"link",		/* 25 = AF_LINK */
113 	"inet6",	/* 26 = AF_INET6 */
114 	"key",		/* 27 = AF_KEY */
115 };
116 
117 /*
118  * Lookup family/type/protocol in /etc/netconfig.
119  * Returns the pathname and a prototype value (to be passed into SO_PROTOTYPE)
120  * The path is malloc'ed and has to be freed by the caller.
121  */
122 int
123 _s_netconfig_path(int family, int type, int protocol,
124 	char **pathp, int *prototype)
125 {
126 	struct netconfig	*net;
127 	void				*nethandle;
128 	struct stat			stats;
129 
130 	net = _s_match_netconf(family, type, protocol, &nethandle);
131 	if (net == NULL)
132 		return (-1);
133 
134 	if (strcmp(net->nc_proto, NC_NOPROTO) != 0)
135 		*prototype = 0;
136 	else
137 		*prototype = protocol;
138 
139 retry:
140 	if (stat(net->nc_device, &stats) < 0) {
141 		switch (errno) {
142 		case EINTR:
143 			goto retry;
144 
145 		case ENOENT:
146 		case ENOLINK:
147 		case ELOOP:
148 		case EMULTIHOP:
149 		case ENOTDIR:
150 			errno = EPFNOSUPPORT;
151 			break;
152 		}
153 		endnetconfig(nethandle); /* finished with netconfig struct */
154 		return (-1);
155 	}
156 	if (!S_ISCHR(stats.st_mode)) {
157 		errno = EPFNOSUPPORT;
158 		endnetconfig(nethandle); /* finished with netconfig struct */
159 		return (-1);
160 	}
161 	*pathp = malloc(strlen(net->nc_device) + 1);
162 	if (*pathp == NULL) {
163 		endnetconfig(nethandle);
164 		errno = ENOMEM;
165 		return (-1);
166 	}
167 	(void) strcpy(*pathp, net->nc_device);
168 	endnetconfig(nethandle); /* finished with netconfig struct */
169 	return (0);
170 }
171 
172 /*
173  * Match config entry for protocol
174  * requested.
175  */
176 static struct netconfig *
177 _s_match_netconf(int family, int type, int proto, void **nethandle)
178 {
179 	struct netconfig	*net;
180 	struct netconfig	*maybe;
181 	char			*oproto;
182 
183 	if (family < 0 ||
184 	    family >= (int)sizeof (family_sw) / (int)sizeof (char *) ||
185 	    proto < 0 || proto >= IPPROTO_MAX)  {
186 		errno = EPROTONOSUPPORT;
187 		return (NULL);
188 	}
189 	if (proto) {
190 		if (proto >= (int)sizeof (proto_sw) / (int)sizeof (char *))
191 			oproto = "";
192 		else
193 			oproto = proto_sw[proto];
194 	}
195 
196 	/*
197 	 * Loop through each entry in netconfig
198 	 * until one matches or we reach the end.
199 	 */
200 	if ((*nethandle = setnetconfig()) == NULL) {
201 		return (NULL);
202 	}
203 
204 	maybe = NULL;
205 	while ((net = getnetconfig(*nethandle)) != NULL) {
206 		/*
207 		 * We make a copy of net->nc_semantics rather than modifying
208 		 * it in place because the network selection code shares the
209 		 * structures returned by getnetconfig() among all its callers.
210 		 * See bug #1160886 for more details.
211 		 */
212 		unsigned int semantics = net->nc_semantics;
213 
214 		if (semantics == NC_TPI_COTS_ORD)
215 			semantics = NC_TPI_COTS;
216 		if (proto) {
217 			if (strcmp(net->nc_protofmly, family_sw[family]) == 0 &&
218 			    semantics == type &&
219 			    strcmp(net->nc_proto, oproto) == 0)
220 				break;
221 
222 			if (strcmp(net->nc_protofmly, family_sw[family]) == 0 &&
223 			    type == SOCK_RAW &&
224 			    semantics == SOCK_RAW &&
225 			    strcmp(net->nc_proto, NC_NOPROTO) == 0 &&
226 			    maybe == NULL)
227 				maybe = net;	/* in case no exact match */
228 
229 			continue;
230 		} else	{
231 			if (strcmp(net->nc_protofmly, family_sw[family]) == 0 &&
232 			    semantics == type) {
233 				break;
234 			}
235 		}
236 	}
237 	if (net == NULL && maybe)
238 		net = maybe;
239 
240 	if (net == NULL) {
241 		endnetconfig(*nethandle);
242 		errno = EPROTONOSUPPORT;
243 		return (NULL);
244 	}
245 
246 	return (net);
247 }
248