1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate /*
30*0Sstevel@tonic-gate  * This program does the following:
31*0Sstevel@tonic-gate  *
32*0Sstevel@tonic-gate  * a) Returns:
33*0Sstevel@tonic-gate  *	0	- if the program successfully determined the net strategy.
34*0Sstevel@tonic-gate  *	!0	- if an error occurred.
35*0Sstevel@tonic-gate  *
36*0Sstevel@tonic-gate  * b) If the program is successful, it prints three tokens to
37*0Sstevel@tonic-gate  *    stdout: <root fs type> <interface name> <net config strategy>.
38*0Sstevel@tonic-gate  *    where:
39*0Sstevel@tonic-gate  *	<root fs type>		-	"nfs" or "ufs"
40*0Sstevel@tonic-gate  *	<interface name>	-	"hme0" or "none"
41*0Sstevel@tonic-gate  *	<net config strategy>	-	"dhcp", "rarp", or "none"
42*0Sstevel@tonic-gate  *
43*0Sstevel@tonic-gate  *    Eg:
44*0Sstevel@tonic-gate  *	# /sbin/netstrategy
45*0Sstevel@tonic-gate  *	ufs hme0 dhcp
46*0Sstevel@tonic-gate  *
47*0Sstevel@tonic-gate  *    <root fs type> identifies the system's root file system type.
48*0Sstevel@tonic-gate  *
49*0Sstevel@tonic-gate  *    <interface name> is the 16 char name of the root interface, and is only
50*0Sstevel@tonic-gate  *	set if rarp/dhcp was used to configure the interface.
51*0Sstevel@tonic-gate  *
52*0Sstevel@tonic-gate  *    <net config strategy> can be either "rarp", "dhcp", or "none" depending
53*0Sstevel@tonic-gate  *	on which strategy was used to configure the interface. Is "none" if
54*0Sstevel@tonic-gate  *	no interface was configured using a net-based strategy.
55*0Sstevel@tonic-gate  *
56*0Sstevel@tonic-gate  * CAVEATS: what about autoclient systems? XXX
57*0Sstevel@tonic-gate  */
58*0Sstevel@tonic-gate 
59*0Sstevel@tonic-gate #include <stdio.h>
60*0Sstevel@tonic-gate #include <stdlib.h>
61*0Sstevel@tonic-gate #include <unistd.h>
62*0Sstevel@tonic-gate #include <string.h>
63*0Sstevel@tonic-gate #include <sys/types.h>
64*0Sstevel@tonic-gate #include <errno.h>
65*0Sstevel@tonic-gate #include <alloca.h>
66*0Sstevel@tonic-gate #include <sys/systeminfo.h>
67*0Sstevel@tonic-gate #include <sys/socket.h>
68*0Sstevel@tonic-gate #include <sys/sockio.h>
69*0Sstevel@tonic-gate #include <net/if.h>
70*0Sstevel@tonic-gate #include <sys/statvfs.h>
71*0Sstevel@tonic-gate 
72*0Sstevel@tonic-gate /* ARGSUSED */
73*0Sstevel@tonic-gate int
74*0Sstevel@tonic-gate main(int argc, char *argv[])
75*0Sstevel@tonic-gate {
76*0Sstevel@tonic-gate 	struct statvfs	vfs;
77*0Sstevel@tonic-gate 	char		*root, *interface, *strategy, dummy;
78*0Sstevel@tonic-gate 	long		len;
79*0Sstevel@tonic-gate 	int		fd, numifs;
80*0Sstevel@tonic-gate 	struct ifreq	*ifr;
81*0Sstevel@tonic-gate 	struct ifconf	ifconf;
82*0Sstevel@tonic-gate 
83*0Sstevel@tonic-gate 	/* root location */
84*0Sstevel@tonic-gate 	if (statvfs("/", &vfs) < 0)
85*0Sstevel@tonic-gate 		root = "none";
86*0Sstevel@tonic-gate 	else {
87*0Sstevel@tonic-gate 		if (strncmp(vfs.f_basetype, "nfs", sizeof ("nfs") - 1) == 0)
88*0Sstevel@tonic-gate 			vfs.f_basetype[sizeof ("nfs") - 1] = '\0';
89*0Sstevel@tonic-gate 		root = vfs.f_basetype;
90*0Sstevel@tonic-gate 	}
91*0Sstevel@tonic-gate 
92*0Sstevel@tonic-gate 	/*
93*0Sstevel@tonic-gate 	 * Handle the simple case where diskless dhcp tells us everything
94*0Sstevel@tonic-gate 	 * we need to know.
95*0Sstevel@tonic-gate 	 */
96*0Sstevel@tonic-gate 	if ((len = sysinfo(SI_DHCP_CACHE, &dummy, sizeof (dummy))) > 1) {
97*0Sstevel@tonic-gate 		/* interface is first thing in cache. */
98*0Sstevel@tonic-gate 		strategy = "dhcp";
99*0Sstevel@tonic-gate 		interface = alloca(len);
100*0Sstevel@tonic-gate 		(void) sysinfo(SI_DHCP_CACHE, interface, len);
101*0Sstevel@tonic-gate 		(void) printf("%s %s %s\n", root, interface, strategy);
102*0Sstevel@tonic-gate 		return (0);
103*0Sstevel@tonic-gate 	}
104*0Sstevel@tonic-gate 
105*0Sstevel@tonic-gate 	/*
106*0Sstevel@tonic-gate 	 * We're not "nfs dhcp", "nfs none" is impossible, and we don't handle
107*0Sstevel@tonic-gate 	 * "ufs rarp" (consumers are coded to deal with this reality), so
108*0Sstevel@tonic-gate 	 * there are three possible situations:
109*0Sstevel@tonic-gate 	 *
110*0Sstevel@tonic-gate 	 *	1. We're "ufs dhcp" if there are any interfaces which have
111*0Sstevel@tonic-gate 	 *	   obtained their addresses through DHCP.  That is, if there
112*0Sstevel@tonic-gate 	 *	   are any IFF_UP and non-IFF_VIRTUAL interfaces also have
113*0Sstevel@tonic-gate 	 *	   IFF_DHCPRUNNING set.
114*0Sstevel@tonic-gate 	 *
115*0Sstevel@tonic-gate 	 *	2. We're "ufs none" if our filesystem is local and there
116*0Sstevel@tonic-gate 	 *	   are no interfaces which have obtained their addresses
117*0Sstevel@tonic-gate 	 *	   through DHCP.
118*0Sstevel@tonic-gate 	 *
119*0Sstevel@tonic-gate 	 *	3. We're "nfs rarp" if our filesystem is remote and there's
120*0Sstevel@tonic-gate 	 *	   at least IFF_UP non-IFF_VIRTUAL interface (which there
121*0Sstevel@tonic-gate 	 *	   *must* be, since we're running over NFS somehow), then
122*0Sstevel@tonic-gate 	 *	   it must be RARP since SI_DHCP_CACHE call above failed.
123*0Sstevel@tonic-gate 	 *	   It's too bad there isn't an IFF_RARPRUNNING flag.
124*0Sstevel@tonic-gate 	 */
125*0Sstevel@tonic-gate 
126*0Sstevel@tonic-gate 	if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
127*0Sstevel@tonic-gate 		(void) fprintf(stderr, "%s: socket: %s\n", argv[0],
128*0Sstevel@tonic-gate 		    strerror(errno));
129*0Sstevel@tonic-gate 		return (2);
130*0Sstevel@tonic-gate 	}
131*0Sstevel@tonic-gate 
132*0Sstevel@tonic-gate 	if (ioctl(fd, SIOCGIFNUM, &numifs) < 0) {
133*0Sstevel@tonic-gate 		(void) fprintf(stderr, "%s: SIOCGIFNUM: %s\n", argv[0],
134*0Sstevel@tonic-gate 		    strerror(errno));
135*0Sstevel@tonic-gate 		(void) close(fd);
136*0Sstevel@tonic-gate 		return (2);
137*0Sstevel@tonic-gate 	}
138*0Sstevel@tonic-gate 
139*0Sstevel@tonic-gate 	ifconf.ifc_len = numifs * sizeof (struct ifreq);
140*0Sstevel@tonic-gate 	ifconf.ifc_buf = alloca(ifconf.ifc_len);
141*0Sstevel@tonic-gate 
142*0Sstevel@tonic-gate 	if (ioctl(fd, SIOCGIFCONF, &ifconf) < 0) {
143*0Sstevel@tonic-gate 		(void) fprintf(stderr, "%s: SIOCGIFCONF: %s\n", argv[0],
144*0Sstevel@tonic-gate 		    strerror(errno));
145*0Sstevel@tonic-gate 		(void) close(fd);
146*0Sstevel@tonic-gate 		return (2);
147*0Sstevel@tonic-gate 	}
148*0Sstevel@tonic-gate 
149*0Sstevel@tonic-gate 	strategy = NULL;
150*0Sstevel@tonic-gate 	interface = NULL;
151*0Sstevel@tonic-gate 
152*0Sstevel@tonic-gate 	for (ifr = ifconf.ifc_req; ifr < &ifconf.ifc_req[ifconf.ifc_len /
153*0Sstevel@tonic-gate 	    sizeof (struct ifreq)]; ifr++) {
154*0Sstevel@tonic-gate 
155*0Sstevel@tonic-gate 		if (strchr(ifr->ifr_name, ':') != NULL)
156*0Sstevel@tonic-gate 			continue;	/* skip virtual interfaces */
157*0Sstevel@tonic-gate 
158*0Sstevel@tonic-gate 		if (ioctl(fd, SIOCGIFFLAGS, ifr) < 0) {
159*0Sstevel@tonic-gate 			(void) fprintf(stderr, "%s: SIOCGIFFLAGS: %s\n",
160*0Sstevel@tonic-gate 			    argv[0], strerror(errno));
161*0Sstevel@tonic-gate 			continue;
162*0Sstevel@tonic-gate 		}
163*0Sstevel@tonic-gate 
164*0Sstevel@tonic-gate 		if (ifr->ifr_flags & (IFF_VIRTUAL|IFF_POINTOPOINT))
165*0Sstevel@tonic-gate 			continue;
166*0Sstevel@tonic-gate 
167*0Sstevel@tonic-gate 		if (ifr->ifr_flags & IFF_UP) {
168*0Sstevel@tonic-gate 			/*
169*0Sstevel@tonic-gate 			 * For the "nfs rarp" case, we assume that the first
170*0Sstevel@tonic-gate 			 * IFF_UP interface is the one using RARP, so stash
171*0Sstevel@tonic-gate 			 * away the first interface in case we need it.
172*0Sstevel@tonic-gate 			 *
173*0Sstevel@tonic-gate 			 * Since the order of the interfaces retrieved via
174*0Sstevel@tonic-gate 			 * SIOCGLIFCONF is not deterministic, this is largely
175*0Sstevel@tonic-gate 			 * silliness, but (a) "it's always been this way", (b)
176*0Sstevel@tonic-gate 			 * machines booted via diskless RARP typically only
177*0Sstevel@tonic-gate 			 * have one interface, and (c) no one consumes the
178*0Sstevel@tonic-gate 			 * interface name in the RARP case anyway.
179*0Sstevel@tonic-gate 			 */
180*0Sstevel@tonic-gate 			if (interface == NULL)
181*0Sstevel@tonic-gate 				interface = ifr->ifr_name;
182*0Sstevel@tonic-gate 
183*0Sstevel@tonic-gate 			if (ifr->ifr_flags & IFF_DHCPRUNNING) {
184*0Sstevel@tonic-gate 				interface = ifr->ifr_name;
185*0Sstevel@tonic-gate 				strategy = "dhcp";
186*0Sstevel@tonic-gate 				break;
187*0Sstevel@tonic-gate 			}
188*0Sstevel@tonic-gate 		}
189*0Sstevel@tonic-gate 	}
190*0Sstevel@tonic-gate 
191*0Sstevel@tonic-gate 	(void) close(fd);
192*0Sstevel@tonic-gate 
193*0Sstevel@tonic-gate 	if (strcmp(root, "nfs") == 0 || strcmp(root, "cachefs") == 0) {
194*0Sstevel@tonic-gate 		if (interface == NULL) {
195*0Sstevel@tonic-gate 			(void) fprintf(stderr,
196*0Sstevel@tonic-gate 			    "%s: cannot identify root interface.\n", argv[0]);
197*0Sstevel@tonic-gate 			return (2);
198*0Sstevel@tonic-gate 		}
199*0Sstevel@tonic-gate 		if (strategy == NULL)
200*0Sstevel@tonic-gate 			strategy = "rarp";	/*  must be rarp/bootparams */
201*0Sstevel@tonic-gate 	} else {
202*0Sstevel@tonic-gate 		if (interface == NULL || strategy == NULL)
203*0Sstevel@tonic-gate 			interface = strategy = "none";
204*0Sstevel@tonic-gate 	}
205*0Sstevel@tonic-gate 
206*0Sstevel@tonic-gate 	(void) printf("%s %s %s\n", root, interface, strategy);
207*0Sstevel@tonic-gate 	return (0);
208*0Sstevel@tonic-gate }
209