xref: /freebsd/sbin/ifconfig/af_link.c (revision 10b94e406444d65af99d344f87d1de320b6cd87e)
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 #ifndef lint
33 static const char rcsid[] =
34   "$FreeBSD$";
35 #endif /* not lint */
36 
37 #include <sys/types.h>
38 #include <sys/ioctl.h>
39 #include <sys/socket.h>
40 #include <net/if.h>
41 
42 #include <err.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <ifaddrs.h>
47 #include <unistd.h>
48 
49 #include <net/if_dl.h>
50 #include <net/if_types.h>
51 #include <net/ethernet.h>
52 
53 #include "ifconfig.h"
54 
55 static struct ifreq link_ridreq;
56 
57 extern char *f_ether;
58 
59 static void
60 print_ether(const struct ether_addr *addr, const char *prefix)
61 {
62 	char *ether_format = ether_ntoa(addr);
63 
64 	if (f_ether != NULL && strcmp(f_ether, "dash") == 0) {
65 		char *format_char;
66 
67 		while ((format_char = strchr(ether_format, ':')) != NULL) {
68 			*format_char = '-';
69 		}
70 	}
71 	printf("\t%s %s\n", prefix, ether_format);
72 }
73 
74 static void
75 print_lladdr(struct sockaddr_dl *sdl)
76 {
77 	if (match_ether(sdl)) {
78 		print_ether((struct ether_addr *)LLADDR(sdl), "ether");
79 	} else {
80 		int n = sdl->sdl_nlen > 0 ? sdl->sdl_nlen + 1 : 0;
81 		printf("\tlladdr %s\n", link_ntoa(sdl) + n);
82 	}
83 }
84 
85 static void
86 print_pcp(int s)
87 {
88 	if (ioctl(s, SIOCGLANPCP, (caddr_t)&ifr) == 0 &&
89 	    ifr.ifr_lan_pcp != IFNET_PCP_NONE)
90 		printf("\tpcp %d\n", ifr.ifr_lan_pcp);
91 }
92 
93 static void
94 link_status(int s __unused, const struct ifaddrs *ifa)
95 {
96 	/* XXX no const 'cuz LLADDR is defined wrong */
97 	struct sockaddr_dl *sdl;
98 	struct ifreq ifr;
99 	int rc, sock_hw;
100 	static const u_char laggaddr[6] = {0};
101 
102 	sdl = (struct sockaddr_dl *) ifa->ifa_addr;
103 	if (sdl == NULL || sdl->sdl_alen == 0)
104 		return;
105 
106 	print_lladdr(sdl);
107 
108 	/*
109 	 * Best-effort (i.e. failures are silent) to get original
110 	 * hardware address, as read by NIC driver at attach time. Only
111 	 * applies to Ethernet NICs (IFT_ETHER). However, laggX
112 	 * interfaces claim to be IFT_ETHER, and re-type their component
113 	 * Ethernet NICs as IFT_IEEE8023ADLAG. So, check for both. If
114 	 * the MAC is zeroed, then it's actually a lagg.
115 	 */
116 	if ((sdl->sdl_type != IFT_ETHER &&
117 	    sdl->sdl_type != IFT_IEEE8023ADLAG) ||
118 	    sdl->sdl_alen != ETHER_ADDR_LEN)
119 		return;
120 
121 	strncpy(ifr.ifr_name, ifa->ifa_name, sizeof(ifr.ifr_name));
122 	memcpy(&ifr.ifr_addr, ifa->ifa_addr, sizeof(ifa->ifa_addr->sa_len));
123 	ifr.ifr_addr.sa_family = AF_LOCAL;
124 	if ((sock_hw = socket(AF_LOCAL, SOCK_DGRAM, 0)) < 0) {
125 		warn("socket(AF_LOCAL,SOCK_DGRAM)");
126 		return;
127 	}
128 	rc = ioctl(sock_hw, SIOCGHWADDR, &ifr);
129 	close(sock_hw);
130 	if (rc != 0)
131 		return;
132 
133 	/*
134 	 * If this is definitely a lagg device or the hwaddr
135 	 * matches the link addr, don't bother.
136 	 */
137 	if (memcmp(ifr.ifr_addr.sa_data, laggaddr, sdl->sdl_alen) == 0 ||
138 	    memcmp(ifr.ifr_addr.sa_data, LLADDR(sdl), sdl->sdl_alen) == 0)
139 		goto pcp;
140 
141 	print_ether((const struct ether_addr *)&ifr.ifr_addr.sa_data, "hwaddr");
142 pcp:
143 	print_pcp(s);
144 }
145 
146 static void
147 link_getaddr(const char *addr, int which)
148 {
149 	char *temp;
150 	struct sockaddr_dl sdl;
151 	struct sockaddr *sa = &link_ridreq.ifr_addr;
152 
153 	if (which != ADDR)
154 		errx(1, "can't set link-level netmask or broadcast");
155 	if (!strcmp(addr, "random")) {
156 		sdl.sdl_len = sizeof(sdl);
157 		sdl.sdl_alen = ETHER_ADDR_LEN;
158 		sdl.sdl_nlen = 0;
159 		sdl.sdl_family = AF_LINK;
160 		arc4random_buf(&sdl.sdl_data, ETHER_ADDR_LEN);
161 		/* Non-multicast and claim it is locally administered. */
162 		sdl.sdl_data[0] &= 0xfc;
163 		sdl.sdl_data[0] |= 0x02;
164 	} else {
165 		if ((temp = malloc(strlen(addr) + 2)) == NULL)
166 			errx(1, "malloc failed");
167 		temp[0] = ':';
168 		strcpy(temp + 1, addr);
169 		sdl.sdl_len = sizeof(sdl);
170 		link_addr(temp, &sdl);
171 		free(temp);
172 	}
173 	if (sdl.sdl_alen > sizeof(sa->sa_data))
174 		errx(1, "malformed link-level address");
175 	sa->sa_family = AF_LINK;
176 	sa->sa_len = sdl.sdl_alen;
177 	bcopy(LLADDR(&sdl), sa->sa_data, sdl.sdl_alen);
178 }
179 
180 static struct afswtch af_link = {
181 	.af_name	= "link",
182 	.af_af		= AF_LINK,
183 	.af_status	= link_status,
184 	.af_getaddr	= link_getaddr,
185 	.af_aifaddr	= SIOCSIFLLADDR,
186 	.af_addreq	= &link_ridreq,
187 };
188 static struct afswtch af_ether = {
189 	.af_name	= "ether",
190 	.af_af		= AF_LINK,
191 	.af_status	= link_status,
192 	.af_getaddr	= link_getaddr,
193 	.af_aifaddr	= SIOCSIFLLADDR,
194 	.af_addreq	= &link_ridreq,
195 };
196 static struct afswtch af_lladdr = {
197 	.af_name	= "lladdr",
198 	.af_af		= AF_LINK,
199 	.af_status	= link_status,
200 	.af_getaddr	= link_getaddr,
201 	.af_aifaddr	= SIOCSIFLLADDR,
202 	.af_addreq	= &link_ridreq,
203 };
204 
205 static __constructor void
206 link_ctor(void)
207 {
208 	af_register(&af_link);
209 	af_register(&af_ether);
210 	af_register(&af_lladdr);
211 }
212