xref: /illumos-gate/usr/src/lib/libsocket/socket/_soutil.c (revision 0250c53ad267726f2438e3c6556199a0bbf588a2)
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 (c) 1995, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
27 /*	  All Rights Reserved   */
28 
29 /*
30  * Portions of this source code were derived from Berkeley 4.3 BSD
31  * under license from the Regents of the University of California.
32  */
33 
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <sys/stat.h>
37 #include <netinet/in.h>
38 #include <errno.h>
39 #include <unistd.h>
40 #include <stdlib.h>
41 #include <string.h>
42 
43 /*
44  * XXX The functions in this file are only needed to support transport
45  * providers that have not yet been converted to use /etc/sock2path.d.
46  * Once all transport providers have been converted this file can be
47  * removed.
48  */
49 
50 static struct netconfig *_s_match_netconf(int family, int type, int proto,
51 		void **nethandle);
52 
53 /*
54  * The following two string arrays map a number as specified
55  * by a user of sockets, to the string as would be returned
56  * by a call to getnetconfig().
57  *
58  * They are used by _s_match_netconf();
59  *
60  * proto_sw contains protocol entries for which there is a corresponding
61  * /dev device. All others would presumably use raw IP and download the
62  * desired protocol.
63  */
64 static char *proto_sw[] = {
65 	"",
66 	"icmp",		/* 1 = ICMP */
67 	"",
68 	"",
69 	"",
70 	"",
71 	"tcp",		/* 6 = TCP */
72 	"",
73 	"",
74 	"",
75 	"",
76 	"",
77 	"",
78 	"",
79 	"",
80 	"",
81 	"",
82 	"udp",		/* 17 = UDP */
83 };
84 
85 static char *family_sw[] = {
86 	"-",		/* 0 = AF_UNSPEC */
87 	"loopback",	/* 1 = AF_UNIX */
88 	"inet",		/* 2 = AF_INET */
89 	"implink",	/* 3 = AF_IMPLINK */
90 	"pup",		/* 4 = AF_PUP */
91 	"chaos",	/* 5 = AF_CHAOS */
92 	"ns",		/* 6 = AF_NS */
93 	"nbs",		/* 7 = AF_NBS */
94 	"ecma",		/* 8 = AF_ECMA */
95 	"datakit",	/* 9 = AF_DATAKIT */
96 	"ccitt",	/* 10 = AF_CCITT */
97 	"sna",		/* 11 = AF_SNA */
98 	"decnet",	/* 12 = AF_DECnet */
99 	"dli",		/* 13 = AF_DLI */
100 	"lat",		/* 14 = AF_LAT */
101 	"hylink",	/* 15 = AF_HYLINK */
102 	"appletalk",	/* 16 = AF_APPLETALK */
103 	"nit",		/* 17 = AF_NIT */
104 	"ieee802",	/* 18 = AF_802 */
105 	"osi",		/* 19 = AF_OSI */
106 	"x25",		/* 20 = AF_X25 */
107 	"osinet",	/* 21 = AF_OSINET */
108 	"gosip",	/* 22 = AF_GOSIP */
109 	"ipx",		/* 23 = AF_IPX */
110 	"route",	/* 24 = AF_ROUTE */
111 	"link",		/* 25 = AF_LINK */
112 	"inet6",	/* 26 = AF_INET6 */
113 	"key",		/* 27 = AF_KEY */
114 };
115 
116 /*
117  * Lookup family/type/protocol in /etc/netconfig.
118  * Returns the pathname and a prototype value (to be passed into SO_PROTOTYPE)
119  * The path is malloc'ed and has to be freed by the caller.
120  */
121 int
122 _s_netconfig_path(int family, int type, int protocol,
123 	char **pathp, int *prototype)
124 {
125 	struct netconfig	*net;
126 	void				*nethandle;
127 	struct stat			stats;
128 
129 	net = _s_match_netconf(family, type, protocol, &nethandle);
130 	if (net == NULL)
131 		return (-1);
132 
133 	if (strcmp(net->nc_proto, NC_NOPROTO) != 0)
134 		*prototype = 0;
135 	else
136 		*prototype = protocol;
137 
138 retry:
139 	if (stat(net->nc_device, &stats) < 0) {
140 		switch (errno) {
141 		case EINTR:
142 			goto retry;
143 
144 		case ENOENT:
145 		case ENOLINK:
146 		case ELOOP:
147 		case EMULTIHOP:
148 		case ENOTDIR:
149 			errno = EPFNOSUPPORT;
150 			break;
151 		}
152 		endnetconfig(nethandle); /* finished with netconfig struct */
153 		return (-1);
154 	}
155 	if (!S_ISCHR(stats.st_mode)) {
156 		errno = EPFNOSUPPORT;
157 		endnetconfig(nethandle); /* finished with netconfig struct */
158 		return (-1);
159 	}
160 	*pathp = malloc(strlen(net->nc_device) + 1);
161 	if (*pathp == NULL) {
162 		endnetconfig(nethandle);
163 		errno = ENOMEM;
164 		return (-1);
165 	}
166 	(void) strcpy(*pathp, net->nc_device);
167 	endnetconfig(nethandle); /* finished with netconfig struct */
168 	return (0);
169 }
170 
171 /*
172  * Match config entry for protocol
173  * requested.
174  */
175 static struct netconfig *
176 _s_match_netconf(int family, int type, int proto, void **nethandle)
177 {
178 	struct netconfig	*net;
179 	struct netconfig	*maybe;
180 	char			*oproto;
181 
182 	if (family < 0 ||
183 	    family >= (int)sizeof (family_sw) / (int)sizeof (char *) ||
184 	    proto < 0 || proto >= IPPROTO_MAX)  {
185 		errno = EPROTONOSUPPORT;
186 		return (NULL);
187 	}
188 	if (proto) {
189 		if (proto >= (int)sizeof (proto_sw) / (int)sizeof (char *))
190 			oproto = "";
191 		else
192 			oproto = proto_sw[proto];
193 	}
194 
195 	/*
196 	 * Loop through each entry in netconfig
197 	 * until one matches or we reach the end.
198 	 */
199 	if ((*nethandle = setnetconfig()) == NULL) {
200 		return (NULL);
201 	}
202 
203 	maybe = NULL;
204 	while ((net = getnetconfig(*nethandle)) != NULL) {
205 		/*
206 		 * We make a copy of net->nc_semantics rather than modifying
207 		 * it in place because the network selection code shares the
208 		 * structures returned by getnetconfig() among all its callers.
209 		 * See bug #1160886 for more details.
210 		 */
211 		unsigned int semantics = net->nc_semantics;
212 
213 		if (semantics == NC_TPI_COTS_ORD)
214 			semantics = NC_TPI_COTS;
215 		if (proto) {
216 			if (strcmp(net->nc_protofmly, family_sw[family]) == 0 &&
217 			    semantics == type &&
218 			    strcmp(net->nc_proto, oproto) == 0)
219 				break;
220 
221 			if (strcmp(net->nc_protofmly, family_sw[family]) == 0 &&
222 			    type == SOCK_RAW &&
223 			    semantics == SOCK_RAW &&
224 			    strcmp(net->nc_proto, NC_NOPROTO) == 0 &&
225 			    maybe == NULL)
226 				maybe = net;	/* in case no exact match */
227 
228 			continue;
229 		} else	{
230 			if (strcmp(net->nc_protofmly, family_sw[family]) == 0 &&
231 			    semantics == type) {
232 				break;
233 			}
234 		}
235 	}
236 	if (net == NULL && maybe)
237 		net = maybe;
238 
239 	if (net == NULL) {
240 		endnetconfig(*nethandle);
241 		errno = EPROTONOSUPPORT;
242 		return (NULL);
243 	}
244 
245 	return (net);
246 }
247