networking/libiproute/iplink.c

/* vi: set sw=4 ts=4: */
/*
 * iplink.c "ip link".
 *
 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

//#include <sys/ioctl.h>
//#include <sys/socket.h>
#include <net/if.h>
#include <net/if_packet.h>
#include <netpacket/packet.h>
#include <net/ethernet.h>

#include "ip_common.h"  /* #include "libbb.h" is inside */
#include "rt_names.h"
#include "utils.h"

/* taken from linux/sockios.h */
#define SIOCSIFNAME	0x8923		/* set interface name */

/* Exits on error */
static int get_ctl_fd(void)
{
	int fd;

	fd = socket(PF_INET, SOCK_DGRAM, 0);
	if (fd >= 0)
		return fd;
	fd = socket(PF_PACKET, SOCK_DGRAM, 0);
	if (fd >= 0)
		return fd;
	return xsocket(PF_INET6, SOCK_DGRAM, 0);
}

/* Exits on error */
static void do_chflags(char *dev, uint32_t flags, uint32_t mask)
{
	struct ifreq ifr;
	int fd;

	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
	fd = get_ctl_fd();
	xioctl(fd, SIOCGIFFLAGS, &ifr);
	if ((ifr.ifr_flags ^ flags) & mask) {
		ifr.ifr_flags &= ~mask;
		ifr.ifr_flags |= mask & flags;
		xioctl(fd, SIOCSIFFLAGS, &ifr);
	}
	close(fd);
}

/* Exits on error */
static void do_changename(char *dev, char *newdev)
{
	struct ifreq ifr;
	int fd;

	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
	strncpy(ifr.ifr_newname, newdev, sizeof(ifr.ifr_newname));
	fd = get_ctl_fd();
	xioctl(fd, SIOCSIFNAME, &ifr);
	close(fd);
}

/* Exits on error */
static void set_qlen(char *dev, int qlen)
{
	struct ifreq ifr;
	int s;

	s = get_ctl_fd();
	memset(&ifr, 0, sizeof(ifr));
	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
	ifr.ifr_qlen = qlen;
	xioctl(s, SIOCSIFTXQLEN, &ifr);
	close(s);
}

/* Exits on error */
static void set_mtu(char *dev, int mtu)
{
	struct ifreq ifr;
	int s;

	s = get_ctl_fd();
	memset(&ifr, 0, sizeof(ifr));
	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
	ifr.ifr_mtu = mtu;
	xioctl(s, SIOCSIFMTU, &ifr);
	close(s);
}

/* Exits on error */
static int get_address(char *dev, int *htype)
{
	struct ifreq ifr;
	struct sockaddr_ll me;
	socklen_t alen;
	int s;

	s = xsocket(PF_PACKET, SOCK_DGRAM, 0);

	memset(&ifr, 0, sizeof(ifr));
	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
	xioctl(s, SIOCGIFINDEX, &ifr);

	memset(&me, 0, sizeof(me));
	me.sll_family = AF_PACKET;
	me.sll_ifindex = ifr.ifr_ifindex;
	me.sll_protocol = htons(ETH_P_LOOP);
	xbind(s, (struct sockaddr*)&me, sizeof(me));

	alen = sizeof(me);
	if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
		bb_perror_msg_and_die("getsockname");
	}
	close(s);
	*htype = me.sll_hatype;
	return me.sll_halen;
}

/* Exits on error */
static void parse_address(char *dev, int hatype, int halen, char *lla, struct ifreq *ifr)
{
	int alen;

	memset(ifr, 0, sizeof(*ifr));
	strncpy(ifr->ifr_name, dev, sizeof(ifr->ifr_name));
	ifr->ifr_hwaddr.sa_family = hatype;

	alen = hatype == 1/*ARPHRD_ETHER*/ ? 14/*ETH_HLEN*/ : 19/*INFINIBAND_HLEN*/;
	alen = ll_addr_a2n((unsigned char *)(ifr->ifr_hwaddr.sa_data), alen, lla);
	if (alen < 0)
		exit(EXIT_FAILURE);
	if (alen != halen) {
		bb_error_msg_and_die("wrong address (%s) length: expected %d bytes", lla, halen);
	}
}

/* Exits on error */
static void set_address(struct ifreq *ifr, int brd)
{
	int s;

	s = get_ctl_fd();
	if (brd)
		xioctl(s, SIOCSIFHWBROADCAST, ifr);
	else
		xioctl(s, SIOCSIFHWADDR, ifr);
	close(s);
}


static void die_must_be_on_off(const char *msg) NORETURN;
static void die_must_be_on_off(const char *msg)
{
	bb_error_msg_and_die("argument of \"%s\" must be \"on\" or \"off\"", msg);
}

/* Return value becomes exitcode. It's okay to not return at all */
static int do_set(char **argv)
{
	char *dev = NULL;
	uint32_t mask = 0;
	uint32_t flags = 0;
	int qlen = -1;
	int mtu = -1;
	char *newaddr = NULL;
	char *newbrd = NULL;
	struct ifreq ifr0, ifr1;
	char *newname = NULL;
	int htype, halen;
	static const char keywords[] ALIGN1 =
		"up\0""down\0""name\0""mtu\0""multicast\0"
		"arp\0""address\0""dev\0";
	enum { ARG_up = 0, ARG_down, ARG_name, ARG_mtu, ARG_multicast,
		ARG_arp, ARG_addr, ARG_dev };
	static const char str_on_off[] ALIGN1 = "on\0""off\0";
	enum { PARM_on = 0, PARM_off };
	smalluint key;

	while (*argv) {
		/* substring search ensures that e.g. "addr" and "address"
		 * are both accepted */
		key = index_in_substrings(keywords, *argv);
		if (key == ARG_up) {
			mask |= IFF_UP;
			flags |= IFF_UP;
		}
		if (key == ARG_down) {
			mask |= IFF_UP;
			flags &= ~IFF_UP;
		}
		if (key == ARG_name) {
			NEXT_ARG();
			newname = *argv;
		}
		if (key == ARG_mtu) {
			NEXT_ARG();
			if (mtu != -1)
				duparg("mtu", *argv);
			if (get_integer(&mtu, *argv, 0))
				invarg(*argv, "mtu");
		}
		if (key == ARG_multicast) {
			int param;
			NEXT_ARG();
			mask |= IFF_MULTICAST;
			param = index_in_strings(str_on_off, *argv);
			if (param < 0)
				die_must_be_on_off("multicast");
			if (param == PARM_on)
				flags |= IFF_MULTICAST;
			else
				flags &= ~IFF_MULTICAST;
		}
		if (key == ARG_arp) {
			int param;
			NEXT_ARG();
			mask |= IFF_NOARP;
			param = index_in_strings(str_on_off, *argv);
			if (param < 0)
				die_must_be_on_off("arp");
			if (param == PARM_on)
				flags &= ~IFF_NOARP;
			else
				flags |= IFF_NOARP;
		}
		if (key == ARG_addr) {
			NEXT_ARG();
			newaddr = *argv;
		}
		if (key >= ARG_dev) {
			if (key == ARG_dev) {
				NEXT_ARG();
			}
			if (dev)
				duparg2("dev", *argv);
			dev = *argv;
		}
		argv++;
	}

	if (!dev) {
		bb_error_msg_and_die(bb_msg_requires_arg, "\"dev\"");
	}

	if (newaddr || newbrd) {
		halen = get_address(dev, &htype);
		if (newaddr) {
			parse_address(dev, htype, halen, newaddr, &ifr0);
		}
		if (newbrd) {
			parse_address(dev, htype, halen, newbrd, &ifr1);
		}
	}

	if (newname && strcmp(dev, newname)) {
		do_changename(dev, newname);
		dev = newname;
	}
	if (qlen != -1) {
		set_qlen(dev, qlen);
	}
	if (mtu != -1) {
		set_mtu(dev, mtu);
	}
	if (newaddr || newbrd) {
		if (newbrd) {
			set_address(&ifr1, 1);
		}
		if (newaddr) {
			set_address(&ifr0, 0);
		}
	}
	if (mask)
		do_chflags(dev, flags, mask);
	return 0;
}

static int ipaddr_list_link(char **argv)
{
	preferred_family = AF_PACKET;
	return ipaddr_list_or_flush(argv, 0);
}

/* Return value becomes exitcode. It's okay to not return at all */
int do_iplink(char **argv)
{
	static const char keywords[] ALIGN1 =
		"set\0""show\0""lst\0""list\0";
	int key;
	if (!*argv)
		return ipaddr_list_link(argv);
	key = index_in_substrings(keywords, *argv);
	if (key < 0)
		bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
	argv++;
	if (key == 0) /* set */
		return do_set(argv);
	/* show, lst, list */
	return ipaddr_list_link(argv);
}
1	niro	532	/* vi: set sw=4 ts=4: */
2			/*
3			* iplink.c "ip link".
4			*
5			* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6			*
7			* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
8			*/
9
10	niro	816	//#include <sys/ioctl.h>
11			//#include <sys/socket.h>
12	niro	532	#include <net/if.h>
13			#include <net/if_packet.h>
14			#include <netpacket/packet.h>
15			#include <net/ethernet.h>
16
17	niro	816	#include "ip_common.h" /* #include "libbb.h" is inside */
18	niro	532	#include "rt_names.h"
19			#include "utils.h"
20
21	niro	816	/* taken from linux/sockios.h */
22	niro	532	#define SIOCSIFNAME 0x8923 /* set interface name */
23
24	niro	816	/* Exits on error */
25	niro	532	static int get_ctl_fd(void)
26			{
27			int fd;
28
29			fd = socket(PF_INET, SOCK_DGRAM, 0);
30			if (fd >= 0)
31			return fd;
32			fd = socket(PF_PACKET, SOCK_DGRAM, 0);
33			if (fd >= 0)
34			return fd;
35	niro	816	return xsocket(PF_INET6, SOCK_DGRAM, 0);
36	niro	532	}
37
38	niro	816	/* Exits on error */
39			static void do_chflags(char *dev, uint32_t flags, uint32_t mask)
40	niro	532	{
41			struct ifreq ifr;
42			int fd;
43
44			strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
45			fd = get_ctl_fd();
46	niro	816	xioctl(fd, SIOCGIFFLAGS, &ifr);
47			if ((ifr.ifr_flags ^ flags) & mask) {
48	niro	532	ifr.ifr_flags &= ~mask;
49	niro	816	ifr.ifr_flags \|= mask & flags;
50			xioctl(fd, SIOCSIFFLAGS, &ifr);
51	niro	532	}
52			close(fd);
53			}
54
55	niro	816	/* Exits on error */
56			static void do_changename(char dev, char newdev)
57	niro	532	{
58			struct ifreq ifr;
59			int fd;
60
61			strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
62			strncpy(ifr.ifr_newname, newdev, sizeof(ifr.ifr_newname));
63			fd = get_ctl_fd();
64	niro	816	xioctl(fd, SIOCSIFNAME, &ifr);
65	niro	532	close(fd);
66			}
67
68	niro	816	/* Exits on error */
69			static void set_qlen(char *dev, int qlen)
70	niro	532	{
71			struct ifreq ifr;
72			int s;
73
74			s = get_ctl_fd();
75			memset(&ifr, 0, sizeof(ifr));
76			strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
77			ifr.ifr_qlen = qlen;
78	niro	816	xioctl(s, SIOCSIFTXQLEN, &ifr);
79	niro	532	close(s);
80			}
81
82	niro	816	/* Exits on error */
83			static void set_mtu(char *dev, int mtu)
84	niro	532	{
85			struct ifreq ifr;
86			int s;
87
88			s = get_ctl_fd();
89			memset(&ifr, 0, sizeof(ifr));
90			strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
91			ifr.ifr_mtu = mtu;
92	niro	816	xioctl(s, SIOCSIFMTU, &ifr);
93	niro	532	close(s);
94			}
95
96	niro	816	/* Exits on error */
97	niro	532	static int get_address(char dev, int htype)
98			{
99			struct ifreq ifr;
100			struct sockaddr_ll me;
101			socklen_t alen;
102			int s;
103
104	niro	816	s = xsocket(PF_PACKET, SOCK_DGRAM, 0);
105	niro	532
106			memset(&ifr, 0, sizeof(ifr));
107			strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
108	niro	816	xioctl(s, SIOCGIFINDEX, &ifr);
109	niro	532
110			memset(&me, 0, sizeof(me));
111			me.sll_family = AF_PACKET;
112			me.sll_ifindex = ifr.ifr_ifindex;
113			me.sll_protocol = htons(ETH_P_LOOP);
114	niro	816	xbind(s, (struct sockaddr*)&me, sizeof(me));
115	niro	532
116			alen = sizeof(me);
117			if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
118	niro	816	bb_perror_msg_and_die("getsockname");
119	niro	532	}
120			close(s);
121			*htype = me.sll_hatype;
122			return me.sll_halen;
123			}
124
125	niro	816	/* Exits on error */
126			static void parse_address(char dev, int hatype, int halen, char lla, struct ifreq *ifr)
127	niro	532	{
128			int alen;
129
130			memset(ifr, 0, sizeof(*ifr));
131			strncpy(ifr->ifr_name, dev, sizeof(ifr->ifr_name));
132			ifr->ifr_hwaddr.sa_family = hatype;
133	niro	816
134			alen = hatype == 1/ARPHRD_ETHER/ ? 14/ETH_HLEN/ : 19/INFINIBAND_HLEN/;
135			alen = ll_addr_a2n((unsigned char *)(ifr->ifr_hwaddr.sa_data), alen, lla);
136	niro	532	if (alen < 0)
137	niro	816	exit(EXIT_FAILURE);
138	niro	532	if (alen != halen) {
139	niro	816	bb_error_msg_and_die("wrong address (%s) length: expected %d bytes", lla, halen);
140	niro	532	}
141			}
142
143	niro	816	/* Exits on error */
144			static void set_address(struct ifreq *ifr, int brd)
145	niro	532	{
146			int s;
147
148			s = get_ctl_fd();
149	niro	816	if (brd)
150			xioctl(s, SIOCSIFHWBROADCAST, ifr);
151			else
152			xioctl(s, SIOCSIFHWADDR, ifr);
153	niro	532	close(s);
154			}
155
156
157	niro	816	static void die_must_be_on_off(const char *msg) NORETURN;
158			static void die_must_be_on_off(const char *msg)
159	niro	532	{
160	niro	816	bb_error_msg_and_die("argument of \"%s\" must be \"on\" or \"off\"", msg);
161			}
162
163			/* Return value becomes exitcode. It's okay to not return at all */
164			static int do_set(char **argv)
165			{
166	niro	532	char *dev = NULL;
167			uint32_t mask = 0;
168			uint32_t flags = 0;
169			int qlen = -1;
170			int mtu = -1;
171			char *newaddr = NULL;
172			char *newbrd = NULL;
173			struct ifreq ifr0, ifr1;
174			char *newname = NULL;
175			int htype, halen;
176	niro	816	static const char keywords[] ALIGN1 =
177			"up\0""down\0""name\0""mtu\0""multicast\0"
178			"arp\0""address\0""dev\0";
179			enum { ARG_up = 0, ARG_down, ARG_name, ARG_mtu, ARG_multicast,
180			ARG_arp, ARG_addr, ARG_dev };
181			static const char str_on_off[] ALIGN1 = "on\0""off\0";
182			enum { PARM_on = 0, PARM_off };
183			smalluint key;
184	niro	532
185	niro	816	while (*argv) {
186			/* substring search ensures that e.g. "addr" and "address"
187			* are both accepted */
188			key = index_in_substrings(keywords, *argv);
189			if (key == ARG_up) {
190	niro	532	mask \|= IFF_UP;
191			flags \|= IFF_UP;
192	niro	816	}
193			if (key == ARG_down) {
194	niro	532	mask \|= IFF_UP;
195			flags &= ~IFF_UP;
196	niro	816	}
197			if (key == ARG_name) {
198	niro	532	NEXT_ARG();
199			newname = *argv;
200	niro	816	}
201			if (key == ARG_mtu) {
202	niro	532	NEXT_ARG();
203			if (mtu != -1)
204			duparg("mtu", *argv);
205			if (get_integer(&mtu, *argv, 0))
206			invarg(*argv, "mtu");
207	niro	816	}
208			if (key == ARG_multicast) {
209			int param;
210	niro	532	NEXT_ARG();
211			mask \|= IFF_MULTICAST;
212	niro	816	param = index_in_strings(str_on_off, *argv);
213			if (param < 0)
214			die_must_be_on_off("multicast");
215			if (param == PARM_on)
216	niro	532	flags \|= IFF_MULTICAST;
217	niro	816	else
218	niro	532	flags &= ~IFF_MULTICAST;
219	niro	816	}
220			if (key == ARG_arp) {
221			int param;
222	niro	532	NEXT_ARG();
223			mask \|= IFF_NOARP;
224	niro	816	param = index_in_strings(str_on_off, *argv);
225			if (param < 0)
226			die_must_be_on_off("arp");
227			if (param == PARM_on)
228	niro	532	flags &= ~IFF_NOARP;
229	niro	816	else
230	niro	532	flags \|= IFF_NOARP;
231	niro	816	}
232			if (key == ARG_addr) {
233	niro	532	NEXT_ARG();
234			newaddr = *argv;
235	niro	816	}
236			if (key >= ARG_dev) {
237			if (key == ARG_dev) {
238	niro	532	NEXT_ARG();
239			}
240			if (dev)
241			duparg2("dev", *argv);
242			dev = *argv;
243			}
244	niro	816	argv++;
245	niro	532	}
246
247			if (!dev) {
248	niro	816	bb_error_msg_and_die(bb_msg_requires_arg, "\"dev\"");
249	niro	532	}
250
251			if (newaddr \|\| newbrd) {
252			halen = get_address(dev, &htype);
253			if (newaddr) {
254	niro	816	parse_address(dev, htype, halen, newaddr, &ifr0);
255	niro	532	}
256			if (newbrd) {
257	niro	816	parse_address(dev, htype, halen, newbrd, &ifr1);
258	niro	532	}
259			}
260
261			if (newname && strcmp(dev, newname)) {
262	niro	816	do_changename(dev, newname);
263	niro	532	dev = newname;
264			}
265			if (qlen != -1) {
266	niro	816	set_qlen(dev, qlen);
267	niro	532	}
268			if (mtu != -1) {
269	niro	816	set_mtu(dev, mtu);
270	niro	532	}
271			if (newaddr \|\| newbrd) {
272			if (newbrd) {
273	niro	816	set_address(&ifr1, 1);
274	niro	532	}
275			if (newaddr) {
276	niro	816	set_address(&ifr0, 0);
277	niro	532	}
278			}
279			if (mask)
280	niro	816	do_chflags(dev, flags, mask);
281	niro	532	return 0;
282			}
283
284	niro	816	static int ipaddr_list_link(char **argv)
285	niro	532	{
286			preferred_family = AF_PACKET;
287	niro	816	return ipaddr_list_or_flush(argv, 0);
288	niro	532	}
289
290	niro	816	/* Return value becomes exitcode. It's okay to not return at all */
291			int do_iplink(char **argv)
292	niro	532	{
293	niro	816	static const char keywords[] ALIGN1 =
294			"set\0""show\0""lst\0""list\0";
295			int key;
296			if (!*argv)
297			return ipaddr_list_link(argv);
298			key = index_in_substrings(keywords, *argv);
299			if (key < 0)
300			bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
301			argv++;
302			if (key == 0) /* set */
303			return do_set(argv);
304			/* show, lst, list */
305			return ipaddr_list_link(argv);
306	niro	532	}