xref: /freebsd/sbin/ifconfig/af_link.c (revision eba230afba4932f02a1ca44efc797cf7499a5cb0)
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 #include <sys/types.h>
33 #include <sys/ioctl.h>
34 #include <sys/socket.h>
35 #include <net/if.h>
36 
37 #include <err.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <ifaddrs.h>
42 #include <unistd.h>
43 
44 #include <net/if_dl.h>
45 #include <net/if_types.h>
46 #include <net/ethernet.h>
47 
48 #include "ifconfig.h"
49 #include "ifconfig_netlink.h"
50 
51 static struct ifreq link_ridreq;
52 
53 extern char *f_ether;
54 
55 static void
print_ether(const struct ether_addr * addr,const char * prefix)56 print_ether(const struct ether_addr *addr, const char *prefix)
57 {
58 	char *ether_format = ether_ntoa(addr);
59 
60 	if (f_ether != NULL) {
61 		if (strcmp(f_ether, "dash") == 0) {
62 			char *format_char;
63 
64 			while ((format_char = strchr(ether_format, ':')) != NULL) {
65 				*format_char = '-';
66 			}
67 		} else if (strcmp(f_ether, "dotted") == 0) {
68 			/* Indices 0 and 1 is kept as is. */
69 			ether_format[ 2] = ether_format[ 3];
70 			ether_format[ 3] = ether_format[ 4];
71 			ether_format[ 4] = '.';
72 			ether_format[ 5] = ether_format[ 6];
73 			ether_format[ 6] = ether_format[ 7];
74 			ether_format[ 7] = ether_format[ 9];
75 			ether_format[ 8] = ether_format[10];
76 			ether_format[ 9] = '.';
77 			ether_format[10] = ether_format[12];
78 			ether_format[11] = ether_format[13];
79 			ether_format[12] = ether_format[15];
80 			ether_format[13] = ether_format[16];
81 			ether_format[14] = '\0';
82 		}
83 	}
84 	printf("\t%s %s\n", prefix, ether_format);
85 }
86 
87 static void
print_lladdr(struct sockaddr_dl * sdl)88 print_lladdr(struct sockaddr_dl *sdl)
89 {
90 	if (match_ether(sdl)) {
91 		print_ether((struct ether_addr *)LLADDR(sdl), "ether");
92 	} else {
93 		int n = sdl->sdl_nlen > 0 ? sdl->sdl_nlen + 1 : 0;
94 		printf("\tlladdr %s\n", link_ntoa(sdl) + n);
95 	}
96 }
97 
98 static void
print_pcp(if_ctx * ctx)99 print_pcp(if_ctx *ctx)
100 {
101 	struct ifreq ifr = {};
102 
103 	if (ioctl_ctx_ifr(ctx, SIOCGLANPCP, &ifr) == 0 &&
104 	    ifr.ifr_lan_pcp != IFNET_PCP_NONE)
105 		printf("\tpcp %d\n", ifr.ifr_lan_pcp);
106 }
107 
108 #ifdef WITHOUT_NETLINK
109 static void
link_status(if_ctx * ctx,const struct ifaddrs * ifa)110 link_status(if_ctx *ctx, const struct ifaddrs *ifa)
111 {
112 	/* XXX no const 'cuz LLADDR is defined wrong */
113 	struct sockaddr_dl *sdl;
114 	struct ifreq ifr;
115 	int rc, sock_hw;
116 	static const u_char laggaddr[6] = {0};
117 
118 	sdl = satosdl(ifa->ifa_addr);
119 	if (sdl == NULL || sdl->sdl_alen == 0)
120 		return;
121 
122 	print_lladdr(sdl);
123 
124 	/*
125 	 * Best-effort (i.e. failures are silent) to get original
126 	 * hardware address, as read by NIC driver at attach time. Only
127 	 * applies to Ethernet NICs (IFT_ETHER). However, laggX
128 	 * interfaces claim to be IFT_ETHER, and re-type their component
129 	 * Ethernet NICs as IFT_IEEE8023ADLAG. So, check for both. If
130 	 * the MAC is zeroed, then it's actually a lagg.
131 	 */
132 	if ((sdl->sdl_type != IFT_ETHER &&
133 	    sdl->sdl_type != IFT_IEEE8023ADLAG) ||
134 	    sdl->sdl_alen != ETHER_ADDR_LEN)
135 		return;
136 
137 	strncpy(ifr.ifr_name, ifa->ifa_name, sizeof(ifr.ifr_name));
138 	memcpy(&ifr.ifr_addr, ifa->ifa_addr, sizeof(ifa->ifa_addr->sa_len));
139 	ifr.ifr_addr.sa_family = AF_LOCAL;
140 	if ((sock_hw = socket(AF_LOCAL, SOCK_DGRAM, 0)) < 0) {
141 		warn("socket(AF_LOCAL,SOCK_DGRAM)");
142 		return;
143 	}
144 	rc = ioctl(sock_hw, SIOCGHWADDR, &ifr);
145 	close(sock_hw);
146 	if (rc != 0)
147 		return;
148 
149 	/*
150 	 * If this is definitely a lagg device or the hwaddr
151 	 * matches the link addr, don't bother.
152 	 */
153 	if (memcmp(ifr.ifr_addr.sa_data, laggaddr, sdl->sdl_alen) == 0 ||
154 	    memcmp(ifr.ifr_addr.sa_data, LLADDR(sdl), sdl->sdl_alen) == 0)
155 		goto pcp;
156 
157 	print_ether((const struct ether_addr *)&ifr.ifr_addr.sa_data, "hwaddr");
158 pcp:
159 	print_pcp(ctx);
160 }
161 
162 #else
163 
164 static void
link_status_nl(if_ctx * ctx,if_link_t * link,if_addr_t * ifa __unused)165 link_status_nl(if_ctx *ctx, if_link_t *link, if_addr_t *ifa __unused)
166 {
167 	if (link->ifla_address != NULL) {
168 		struct sockaddr_dl sdl = {
169 			.sdl_len = sizeof(struct sockaddr_dl),
170 			.sdl_family = AF_LINK,
171 			.sdl_type = convert_iftype(link->ifi_type),
172 			.sdl_alen = NLA_DATA_LEN(link->ifla_address),
173 		};
174 		memcpy(LLADDR(&sdl), NLA_DATA(link->ifla_address), sdl.sdl_alen);
175 		print_lladdr(&sdl);
176 
177 		if (link->iflaf_orig_hwaddr != NULL) {
178 			struct nlattr *hwaddr = link->iflaf_orig_hwaddr;
179 
180 			if (memcmp(NLA_DATA(hwaddr), NLA_DATA(link->ifla_address), sdl.sdl_alen))
181 				print_ether((struct ether_addr *)NLA_DATA(hwaddr), "hwaddr");
182 		}
183 	}
184 	if (convert_iftype(link->ifi_type) == IFT_ETHER)
185 		print_pcp(ctx);
186 }
187 #endif
188 
189 static void
link_getaddr(const char * addr,int which)190 link_getaddr(const char *addr, int which)
191 {
192 	char *temp;
193 	struct sockaddr_dl sdl;
194 	struct sockaddr *sa = &link_ridreq.ifr_addr;
195 
196 	if (which != ADDR)
197 		errx(1, "can't set link-level netmask or broadcast");
198 	if (!strcmp(addr, "random")) {
199 		sdl.sdl_len = sizeof(sdl);
200 		sdl.sdl_alen = ETHER_ADDR_LEN;
201 		sdl.sdl_nlen = 0;
202 		sdl.sdl_family = AF_LINK;
203 		arc4random_buf(&sdl.sdl_data, ETHER_ADDR_LEN);
204 		/* Non-multicast and claim it is locally administered. */
205 		sdl.sdl_data[0] &= 0xfc;
206 		sdl.sdl_data[0] |= 0x02;
207 	} else {
208 		if ((temp = malloc(strlen(addr) + 2)) == NULL)
209 			errx(1, "malloc failed");
210 		temp[0] = ':';
211 		strcpy(temp + 1, addr);
212 		sdl.sdl_len = sizeof(sdl);
213 		link_addr(temp, &sdl);
214 		free(temp);
215 	}
216 	if (sdl.sdl_alen > sizeof(sa->sa_data))
217 		errx(1, "malformed link-level address");
218 	sa->sa_family = AF_LINK;
219 	sa->sa_len = sdl.sdl_alen;
220 	bcopy(LLADDR(&sdl), sa->sa_data, sdl.sdl_alen);
221 }
222 
223 static struct afswtch af_link = {
224 	.af_name	= "link",
225 	.af_af		= AF_LINK,
226 #ifdef WITHOUT_NETLINK
227 	.af_status	= link_status,
228 #else
229 	.af_status	= link_status_nl,
230 #endif
231 	.af_getaddr	= link_getaddr,
232 	.af_aifaddr	= SIOCSIFLLADDR,
233 	.af_addreq	= &link_ridreq,
234 	.af_exec	= af_exec_ioctl,
235 };
236 static struct afswtch af_ether = {
237 	.af_name	= "ether",
238 	.af_af		= AF_LINK,
239 #ifdef WITHOUT_NETLINK
240 	.af_status	= link_status,
241 #else
242 	.af_status	= link_status_nl,
243 #endif
244 	.af_getaddr	= link_getaddr,
245 	.af_aifaddr	= SIOCSIFLLADDR,
246 	.af_addreq	= &link_ridreq,
247 	.af_exec	= af_exec_ioctl,
248 };
249 static struct afswtch af_lladdr = {
250 	.af_name	= "lladdr",
251 	.af_af		= AF_LINK,
252 #ifdef WITHOUT_NETLINK
253 	.af_status	= link_status,
254 #else
255 	.af_status	= link_status_nl,
256 #endif
257 	.af_getaddr	= link_getaddr,
258 	.af_aifaddr	= SIOCSIFLLADDR,
259 	.af_addreq	= &link_ridreq,
260 	.af_exec	= af_exec_ioctl,
261 };
262 
263 static __constructor void
link_ctor(void)264 link_ctor(void)
265 {
266 	af_register(&af_link);
267 	af_register(&af_ether);
268 	af_register(&af_lladdr);
269 }
270