xref: /freebsd/sbin/ifconfig/af_link.c (revision 5aa839c9e2c373275091b8bf529c1311d0b84d76)
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  link_status(int s __unused, const struct ifaddrs *ifa)
61  {
62  	/* XXX no const 'cuz LLADDR is defined wrong */
63  	struct sockaddr_dl *sdl;
64  	char *ether_format, *format_char;
65  	struct ifreq ifr;
66  	int n, rc, sock_hw;
67  	static const u_char laggaddr[6] = {0};
68  
69  	sdl = (struct sockaddr_dl *) ifa->ifa_addr;
70  	if (sdl == NULL || sdl->sdl_alen == 0)
71  		return;
72  
73  	if ((sdl->sdl_type == IFT_ETHER || sdl->sdl_type == IFT_L2VLAN ||
74  	    sdl->sdl_type == IFT_BRIDGE) && sdl->sdl_alen == ETHER_ADDR_LEN) {
75  		ether_format = ether_ntoa((struct ether_addr *)LLADDR(sdl));
76  		if (f_ether != NULL && strcmp(f_ether, "dash") == 0) {
77  			while ((format_char = strchr(ether_format, ':')) !=
78  			    NULL) {
79  				*format_char = '-';
80  			}
81  		}
82  		printf("\tether %s\n", ether_format);
83  	} else {
84  		n = sdl->sdl_nlen > 0 ? sdl->sdl_nlen + 1 : 0;
85  		printf("\tlladdr %s\n", link_ntoa(sdl) + n);
86  	}
87  
88  	/*
89  	 * Best-effort (i.e. failures are silent) to get original
90  	 * hardware address, as read by NIC driver at attach time. Only
91  	 * applies to Ethernet NICs (IFT_ETHER). However, laggX
92  	 * interfaces claim to be IFT_ETHER, and re-type their component
93  	 * Ethernet NICs as IFT_IEEE8023ADLAG. So, check for both. If
94  	 * the MAC is zeroed, then it's actually a lagg.
95  	 */
96  	if ((sdl->sdl_type != IFT_ETHER &&
97  	    sdl->sdl_type != IFT_IEEE8023ADLAG) ||
98  	    sdl->sdl_alen != ETHER_ADDR_LEN)
99  		return;
100  
101  	strncpy(ifr.ifr_name, ifa->ifa_name, sizeof(ifr.ifr_name));
102  	memcpy(&ifr.ifr_addr, ifa->ifa_addr, sizeof(ifa->ifa_addr->sa_len));
103  	ifr.ifr_addr.sa_family = AF_LOCAL;
104  	if ((sock_hw = socket(AF_LOCAL, SOCK_DGRAM, 0)) < 0) {
105  		warn("socket(AF_LOCAL,SOCK_DGRAM)");
106  		return;
107  	}
108  	rc = ioctl(sock_hw, SIOCGHWADDR, &ifr);
109  	close(sock_hw);
110  	if (rc != 0)
111  		return;
112  
113  	/*
114  	 * If this is definitely a lagg device or the hwaddr
115  	 * matches the link addr, don't bother.
116  	 */
117  	if (memcmp(ifr.ifr_addr.sa_data, laggaddr, sdl->sdl_alen) == 0 ||
118  	    memcmp(ifr.ifr_addr.sa_data, LLADDR(sdl), sdl->sdl_alen) == 0)
119  		goto pcp;
120  
121  	ether_format = ether_ntoa((const struct ether_addr *)
122  	    &ifr.ifr_addr.sa_data);
123  	if (f_ether != NULL && strcmp(f_ether, "dash") == 0) {
124  		for (format_char = strchr(ether_format, ':');
125  		     format_char != NULL;
126  		     format_char = strchr(ether_format, ':'))
127  			*format_char = '-';
128  	}
129  	printf("\thwaddr %s\n", ether_format);
130  
131  pcp:
132  	if (ioctl(s, SIOCGLANPCP, (caddr_t)&ifr) == 0 &&
133  	    ifr.ifr_lan_pcp != IFNET_PCP_NONE)
134  		printf("\tpcp %d\n", ifr.ifr_lan_pcp);
135  }
136  
137  static void
138  link_getaddr(const char *addr, int which)
139  {
140  	char *temp;
141  	struct sockaddr_dl sdl;
142  	struct sockaddr *sa = &link_ridreq.ifr_addr;
143  
144  	if (which != ADDR)
145  		errx(1, "can't set link-level netmask or broadcast");
146  	if (!strcmp(addr, "random")) {
147  		sdl.sdl_len = sizeof(sdl);
148  		sdl.sdl_alen = ETHER_ADDR_LEN;
149  		sdl.sdl_nlen = 0;
150  		sdl.sdl_family = AF_LINK;
151  		arc4random_buf(&sdl.sdl_data, ETHER_ADDR_LEN);
152  		/* Non-multicast and claim it is locally administered. */
153  		sdl.sdl_data[0] &= 0xfc;
154  		sdl.sdl_data[0] |= 0x02;
155  	} else {
156  		if ((temp = malloc(strlen(addr) + 2)) == NULL)
157  			errx(1, "malloc failed");
158  		temp[0] = ':';
159  		strcpy(temp + 1, addr);
160  		sdl.sdl_len = sizeof(sdl);
161  		link_addr(temp, &sdl);
162  		free(temp);
163  	}
164  	if (sdl.sdl_alen > sizeof(sa->sa_data))
165  		errx(1, "malformed link-level address");
166  	sa->sa_family = AF_LINK;
167  	sa->sa_len = sdl.sdl_alen;
168  	bcopy(LLADDR(&sdl), sa->sa_data, sdl.sdl_alen);
169  }
170  
171  static struct afswtch af_link = {
172  	.af_name	= "link",
173  	.af_af		= AF_LINK,
174  	.af_status	= link_status,
175  	.af_getaddr	= link_getaddr,
176  	.af_aifaddr	= SIOCSIFLLADDR,
177  	.af_addreq	= &link_ridreq,
178  };
179  static struct afswtch af_ether = {
180  	.af_name	= "ether",
181  	.af_af		= AF_LINK,
182  	.af_status	= link_status,
183  	.af_getaddr	= link_getaddr,
184  	.af_aifaddr	= SIOCSIFLLADDR,
185  	.af_addreq	= &link_ridreq,
186  };
187  static struct afswtch af_lladdr = {
188  	.af_name	= "lladdr",
189  	.af_af		= AF_LINK,
190  	.af_status	= link_status,
191  	.af_getaddr	= link_getaddr,
192  	.af_aifaddr	= SIOCSIFLLADDR,
193  	.af_addreq	= &link_ridreq,
194  };
195  
196  static __constructor void
197  link_ctor(void)
198  {
199  	af_register(&af_link);
200  	af_register(&af_ether);
201  	af_register(&af_lladdr);
202  }
203