1/* vi: set sw=4 ts=4: */
2/* ifconfig
3 *
4 * Similar to the standard Unix ifconfig, but with only the necessary
5 * parts for AF_INET, and without any printing of if info (for now).
6 *
7 * Bjorn Wesen, Axis Communications AB
8 *
9 *
10 * Authors of the original ifconfig was:
11 *              Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
12 *
13 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
14 */
15
16/*
17 * Heavily modified by Manuel Novoa III       Mar 6, 2001
18 *
19 * From initial port to busybox, removed most of the redundancy by
20 * converting to a table-driven approach.  Added several (optional)
21 * args missing from initial port.
22 *
23 * Still missing:  media, tunnel.
24 *
25 * 2002-04-20
26 * IPV6 support added by Bart Visscher <magick@linux-fan.com>
27 */
28
29#include <net/if.h>
30#include <net/if_arp.h>
31#include <netinet/in.h>
32#if defined(__GLIBC__) && __GLIBC__ >=2 && __GLIBC_MINOR__ >= 1
33#include <netpacket/packet.h>
34#include <net/ethernet.h>
35#else
36#include <sys/types.h>
37#include <netinet/if_ether.h>
38#endif
39#include "inet_common.h"
40#include "libbb.h"
41
42#if ENABLE_FEATURE_IFCONFIG_SLIP
43# include <net/if_slip.h>
44#endif
45
46/* I don't know if this is needed for busybox or not.  Anyone? */
47#define QUESTIONABLE_ALIAS_CASE
48
49
50/* Defines for glibc2.0 users. */
51#ifndef SIOCSIFTXQLEN
52# define SIOCSIFTXQLEN      0x8943
53# define SIOCGIFTXQLEN      0x8942
54#endif
55
56/* ifr_qlen is ifru_ivalue, but it isn't present in 2.0 kernel headers */
57#ifndef ifr_qlen
58# define ifr_qlen        ifr_ifru.ifru_mtu
59#endif
60
61#ifndef IFF_DYNAMIC
62# define IFF_DYNAMIC     0x8000	/* dialup device with changing addresses */
63#endif
64
65#if ENABLE_FEATURE_IPV6
66struct in6_ifreq {
67	struct in6_addr ifr6_addr;
68	uint32_t ifr6_prefixlen;
69	int ifr6_ifindex;
70};
71#endif
72
73/*
74 * Here are the bit masks for the "flags" member of struct options below.
75 * N_ signifies no arg prefix; M_ signifies arg prefixed by '-'.
76 * CLR clears the flag; SET sets the flag; ARG signifies (optional) arg.
77 */
78#define N_CLR            0x01
79#define M_CLR            0x02
80#define N_SET            0x04
81#define M_SET            0x08
82#define N_ARG            0x10
83#define M_ARG            0x20
84
85#define M_MASK           (M_CLR | M_SET | M_ARG)
86#define N_MASK           (N_CLR | N_SET | N_ARG)
87#define SET_MASK         (N_SET | M_SET)
88#define CLR_MASK         (N_CLR | M_CLR)
89#define SET_CLR_MASK     (SET_MASK | CLR_MASK)
90#define ARG_MASK         (M_ARG | N_ARG)
91
92/*
93 * Here are the bit masks for the "arg_flags" member of struct options below.
94 */
95
96/*
97 * cast type:
98 *   00 int
99 *   01 char *
100 *   02 HOST_COPY in_ether
101 *   03 HOST_COPY INET_resolve
102 */
103#define A_CAST_TYPE      0x03
104/*
105 * map type:
106 *   00 not a map type (mem_start, io_addr, irq)
107 *   04 memstart (unsigned long)
108 *   08 io_addr  (unsigned short)
109 *   0C irq      (unsigned char)
110 */
111#define A_MAP_TYPE       0x0C
112#define A_ARG_REQ        0x10	/* Set if an arg is required. */
113#define A_NETMASK        0x20	/* Set if netmask (check for multiple sets). */
114#define A_SET_AFTER      0x40	/* Set a flag at the end. */
115#define A_COLON_CHK      0x80	/* Is this needed?  See below. */
116#if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
117#define A_HOSTNAME      0x100	/* Set if it is ip addr. */
118#define A_BROADCAST     0x200	/* Set if it is broadcast addr. */
119#else
120#define A_HOSTNAME          0
121#define A_BROADCAST         0
122#endif
123
124/*
125 * These defines are for dealing with the A_CAST_TYPE field.
126 */
127#define A_CAST_CHAR_PTR  0x01
128#define A_CAST_RESOLVE   0x01
129#define A_CAST_HOST_COPY 0x02
130#define A_CAST_HOST_COPY_IN_ETHER    A_CAST_HOST_COPY
131#define A_CAST_HOST_COPY_RESOLVE     (A_CAST_HOST_COPY | A_CAST_RESOLVE)
132
133/*
134 * These defines are for dealing with the A_MAP_TYPE field.
135 */
136#define A_MAP_ULONG      0x04	/* memstart */
137#define A_MAP_USHORT     0x08	/* io_addr */
138#define A_MAP_UCHAR      0x0C	/* irq */
139
140/*
141 * Define the bit masks signifying which operations to perform for each arg.
142 */
143
144#define ARG_METRIC       (A_ARG_REQ /*| A_CAST_INT*/)
145#define ARG_MTU          (A_ARG_REQ /*| A_CAST_INT*/)
146#define ARG_TXQUEUELEN   (A_ARG_REQ /*| A_CAST_INT*/)
147#define ARG_MEM_START    (A_ARG_REQ | A_MAP_ULONG)
148#define ARG_IO_ADDR      (A_ARG_REQ | A_MAP_ULONG)
149#define ARG_IRQ          (A_ARG_REQ | A_MAP_UCHAR)
150#define ARG_DSTADDR      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE)
151#define ARG_NETMASK      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_NETMASK)
152#define ARG_BROADCAST    (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_BROADCAST)
153#define ARG_HW           (A_ARG_REQ | A_CAST_HOST_COPY_IN_ETHER)
154#define ARG_POINTOPOINT  (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
155#define ARG_KEEPALIVE    (A_ARG_REQ | A_CAST_CHAR_PTR)
156#define ARG_OUTFILL      (A_ARG_REQ | A_CAST_CHAR_PTR)
157#define ARG_HOSTNAME     (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_COLON_CHK | A_HOSTNAME)
158#define ARG_ADD_DEL      (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
159
160
161/*
162 * Set up the tables.  Warning!  They must have corresponding order!
163 */
164
165struct arg1opt {
166	const char *name;
167	int selector;
168	unsigned short ifr_offset;
169};
170
171struct options {
172	const char *name;
173#if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
174	const unsigned int flags:6;
175	const unsigned int arg_flags:10;
176#else
177	const unsigned char flags;
178	const unsigned char arg_flags;
179#endif
180	const unsigned short selector;
181};
182
183#define ifreq_offsetof(x)  offsetof(struct ifreq, x)
184
185static const struct arg1opt Arg1Opt[] = {
186	{"SIOCSIFMETRIC",  SIOCSIFMETRIC,  ifreq_offsetof(ifr_metric)},
187	{"SIOCSIFMTU",     SIOCSIFMTU,     ifreq_offsetof(ifr_mtu)},
188	{"SIOCSIFTXQLEN",  SIOCSIFTXQLEN,  ifreq_offsetof(ifr_qlen)},
189	{"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
190	{"SIOCSIFNETMASK", SIOCSIFNETMASK, ifreq_offsetof(ifr_netmask)},
191	{"SIOCSIFBRDADDR", SIOCSIFBRDADDR, ifreq_offsetof(ifr_broadaddr)},
192#if ENABLE_FEATURE_IFCONFIG_HW
193	{"SIOCSIFHWADDR",  SIOCSIFHWADDR,  ifreq_offsetof(ifr_hwaddr)},
194#endif
195	{"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
196#ifdef SIOCSKEEPALIVE
197	{"SIOCSKEEPALIVE", SIOCSKEEPALIVE, ifreq_offsetof(ifr_data)},
198#endif
199#ifdef SIOCSOUTFILL
200	{"SIOCSOUTFILL",   SIOCSOUTFILL,   ifreq_offsetof(ifr_data)},
201#endif
202#if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
203	{"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.mem_start)},
204	{"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.base_addr)},
205	{"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.irq)},
206#endif
207	/* Last entry if for unmatched (possibly hostname) arg. */
208#if ENABLE_FEATURE_IPV6
209	{"SIOCSIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr)}, /* IPv6 version ignores the offset */
210	{"SIOCDIFADDR",    SIOCDIFADDR,    ifreq_offsetof(ifr_addr)}, /* IPv6 version ignores the offset */
211#endif
212	{"SIOCSIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr)},
213};
214
215static const struct options OptArray[] = {
216	{"metric",      N_ARG,         ARG_METRIC,      0},
217	{"mtu",         N_ARG,         ARG_MTU,         0},
218	{"txqueuelen",  N_ARG,         ARG_TXQUEUELEN,  0},
219	{"dstaddr",     N_ARG,         ARG_DSTADDR,     0},
220	{"netmask",     N_ARG,         ARG_NETMASK,     0},
221	{"broadcast",   N_ARG | M_CLR, ARG_BROADCAST,   IFF_BROADCAST},
222#if ENABLE_FEATURE_IFCONFIG_HW
223	{"hw",          N_ARG, ARG_HW,                  0},
224#endif
225	{"pointopoint", N_ARG | M_CLR, ARG_POINTOPOINT, IFF_POINTOPOINT},
226#ifdef SIOCSKEEPALIVE
227	{"keepalive",   N_ARG,         ARG_KEEPALIVE,   0},
228#endif
229#ifdef SIOCSOUTFILL
230	{"outfill",     N_ARG,         ARG_OUTFILL,     0},
231#endif
232#if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
233	{"mem_start",   N_ARG,         ARG_MEM_START,   0},
234	{"io_addr",     N_ARG,         ARG_IO_ADDR,     0},
235	{"irq",         N_ARG,         ARG_IRQ,         0},
236#endif
237#if ENABLE_FEATURE_IPV6
238	{"add",         N_ARG,         ARG_ADD_DEL,     0},
239	{"del",         N_ARG,         ARG_ADD_DEL,     0},
240#endif
241	{"arp",         N_CLR | M_SET, 0,               IFF_NOARP},
242	{"trailers",    N_CLR | M_SET, 0,               IFF_NOTRAILERS},
243	{"promisc",     N_SET | M_CLR, 0,               IFF_PROMISC},
244	{"multicast",   N_SET | M_CLR, 0,               IFF_MULTICAST},
245	{"allmulti",    N_SET | M_CLR, 0,               IFF_ALLMULTI},
246	{"dynamic",     N_SET | M_CLR, 0,               IFF_DYNAMIC},
247	{"up",          N_SET,         0,               (IFF_UP | IFF_RUNNING)},
248	{"down",        N_CLR,         0,               IFF_UP},
249	{NULL,          0,             ARG_HOSTNAME,    (IFF_UP | IFF_RUNNING)}
250};
251
252/*
253 * A couple of prototypes.
254 */
255
256#if ENABLE_FEATURE_IFCONFIG_HW
257static int in_ether(const char *bufp, struct sockaddr *sap);
258#endif
259
260/*
261 * Our main function.
262 */
263
264int ifconfig_main(int argc, char **argv);
265int ifconfig_main(int argc, char **argv)
266{
267	struct ifreq ifr;
268	struct sockaddr_in sai;
269#if ENABLE_FEATURE_IFCONFIG_HW
270	struct sockaddr sa;
271#endif
272	const struct arg1opt *a1op;
273	const struct options *op;
274	int sockfd;			/* socket fd we use to manipulate stuff with */
275	int selector;
276#if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
277	unsigned int mask;
278	unsigned int did_flags;
279	unsigned int sai_hostname, sai_netmask;
280#else
281	unsigned char mask;
282	unsigned char did_flags;
283#endif
284	char *p;
285	/*char host[128];*/
286	const char *host = NULL; /* make gcc happy */
287
288	did_flags = 0;
289#if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
290	sai_hostname = 0;
291	sai_netmask = 0;
292#endif
293
294	/* skip argv[0] */
295	++argv;
296	--argc;
297
298#if ENABLE_FEATURE_IFCONFIG_STATUS
299	if (argc > 0 && (argv[0][0] == '-' && argv[0][1] == 'a' && !argv[0][2])) {
300		interface_opt_a = 1;
301		--argc;
302		++argv;
303	}
304#endif
305
306	if (argc <= 1) {
307#if ENABLE_FEATURE_IFCONFIG_STATUS
308		return display_interfaces(argc ? *argv : NULL);
309#else
310		bb_error_msg_and_die("no support for status display");
311#endif
312	}
313
314	/* Create a channel to the NET kernel. */
315	sockfd = xsocket(AF_INET, SOCK_DGRAM, 0);
316
317	/* get interface name */
318	safe_strncpy(ifr.ifr_name, *argv, IFNAMSIZ);
319
320	/* Process the remaining arguments. */
321	while (*++argv != (char *) NULL) {
322		p = *argv;
323		mask = N_MASK;
324		if (*p == '-') {	/* If the arg starts with '-'... */
325			++p;		/*    advance past it and */
326			mask = M_MASK;	/*    set the appropriate mask. */
327		}
328		for (op = OptArray; op->name; op++) {	/* Find table entry. */
329			if (strcmp(p, op->name) == 0) {	/* If name matches... */
330				mask &= op->flags;
331				if (mask)	/* set the mask and go. */
332					goto FOUND_ARG;
333				/* If we get here, there was a valid arg with an */
334				/* invalid '-' prefix. */
335				bb_error_msg_and_die("bad: '%s'", p-1);
336			}
337		}
338
339		/* We fell through, so treat as possible hostname. */
340		a1op = Arg1Opt + ARRAY_SIZE(Arg1Opt) - 1;
341		mask = op->arg_flags;
342		goto HOSTNAME;
343
344 FOUND_ARG:
345		if (mask & ARG_MASK) {
346			mask = op->arg_flags;
347			a1op = Arg1Opt + (op - OptArray);
348			if (mask & A_NETMASK & did_flags)
349				bb_show_usage();
350			if (*++argv == NULL) {
351				if (mask & A_ARG_REQ)
352					bb_show_usage();
353				--argv;
354				mask &= A_SET_AFTER;	/* just for broadcast */
355			} else {	/* got an arg so process it */
356 HOSTNAME:
357				did_flags |= (mask & (A_NETMASK|A_HOSTNAME));
358				if (mask & A_CAST_HOST_COPY) {
359#if ENABLE_FEATURE_IFCONFIG_HW
360					if (mask & A_CAST_RESOLVE) {
361#endif
362#if ENABLE_FEATURE_IPV6
363						char *prefix;
364						int prefix_len = 0;
365#endif
366						/*safe_strncpy(host, *argv, (sizeof host));*/
367						host = *argv;
368#if ENABLE_FEATURE_IPV6
369						prefix = strchr(host, '/');
370						if (prefix) {
371							prefix_len = xatou_range(prefix + 1, 0, 128);
372							*prefix = '\0';
373						}
374#endif
375						sai.sin_family = AF_INET;
376						sai.sin_port = 0;
377						if (!strcmp(host, bb_str_default)) {
378							/* Default is special, meaning 0.0.0.0. */
379							sai.sin_addr.s_addr = INADDR_ANY;
380						}
381#if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
382						else if ((host[0] == '+' && !host[1]) && (mask & A_BROADCAST)
383						 && (did_flags & (A_NETMASK|A_HOSTNAME)) == (A_NETMASK|A_HOSTNAME)
384						) {
385							/* + is special, meaning broadcast is derived. */
386							sai.sin_addr.s_addr = (~sai_netmask) | (sai_hostname & sai_netmask);
387						}
388#endif
389						else {
390							len_and_sockaddr *lsa;
391							if (strcmp(host, "inet") == 0)
392								continue; /* compat stuff */
393							lsa = xhost2sockaddr(host, 0);
394#if ENABLE_FEATURE_IPV6
395							if (lsa->sa.sa_family == AF_INET6) {
396								int sockfd6;
397								struct in6_ifreq ifr6;
398
399								memcpy((char *) &ifr6.ifr6_addr,
400										(char *) &(lsa->sin6.sin6_addr),
401										sizeof(struct in6_addr));
402
403								/* Create a channel to the NET kernel. */
404								sockfd6 = xsocket(AF_INET6, SOCK_DGRAM, 0);
405								xioctl(sockfd6, SIOGIFINDEX, &ifr);
406								ifr6.ifr6_ifindex = ifr.ifr_ifindex;
407								ifr6.ifr6_prefixlen = prefix_len;
408								ioctl_or_perror_and_die(sockfd6, a1op->selector, &ifr6, "%s", a1op->name);
409								if (ENABLE_FEATURE_CLEAN_UP)
410									free(lsa);
411								continue;
412							}
413#endif
414							sai.sin_addr = lsa->sin.sin_addr;
415							if (ENABLE_FEATURE_CLEAN_UP)
416								free(lsa);
417						}
418#if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
419						if (mask & A_HOSTNAME)
420							sai_hostname = sai.sin_addr.s_addr;
421						if (mask & A_NETMASK)
422							sai_netmask = sai.sin_addr.s_addr;
423#endif
424						p = (char *) &sai;
425#if ENABLE_FEATURE_IFCONFIG_HW
426					} else {	/* A_CAST_HOST_COPY_IN_ETHER */
427						/* This is the "hw" arg case. */
428						if (strcmp("ether", *argv) || !*++argv)
429							bb_show_usage();
430						/*safe_strncpy(host, *argv, sizeof(host));*/
431						host = *argv;
432						if (in_ether(host, &sa))
433							bb_error_msg_and_die("invalid hw-addr %s", host);
434						p = (char *) &sa;
435					}
436#endif
437					memcpy( (((char *)&ifr) + a1op->ifr_offset),
438						   p, sizeof(struct sockaddr));
439				} else {
440					unsigned long i = strtoul(*argv, NULL, 0);
441					p = ((char *)&ifr) + a1op->ifr_offset;
442#if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
443					if (mask & A_MAP_TYPE) {
444						xioctl(sockfd, SIOCGIFMAP, &ifr);
445						if ((mask & A_MAP_UCHAR) == A_MAP_UCHAR)
446							*((unsigned char *) p) = i;
447						else if (mask & A_MAP_USHORT)
448							*((unsigned short *) p) = i;
449						else
450							*((unsigned long *) p) = i;
451					} else
452#endif
453					if (mask & A_CAST_CHAR_PTR)
454						*((caddr_t *) p) = (caddr_t) i;
455					else	/* A_CAST_INT */
456						*((int *) p) = i;
457				}
458
459				ioctl_or_perror_and_die(sockfd, a1op->selector, &ifr, "%s", a1op->name);
460#ifdef QUESTIONABLE_ALIAS_CASE
461				if (mask & A_COLON_CHK) {
462					/*
463					 * Don't do the set_flag() if the address is an alias with
464					 * a '-' at the end, since it's deleted already! - Roman
465					 *
466					 * Should really use regex.h here, not sure though how well
467					 * it'll go with the cross-platform support etc.
468					 */
469					char *ptr;
470					short int found_colon = 0;
471					for (ptr = ifr.ifr_name; *ptr; ptr++)
472						if (*ptr == ':')
473							found_colon++;
474					if (found_colon && ptr[-1] == '-')
475						continue;
476				}
477#endif
478			}
479			if (!(mask & A_SET_AFTER))
480				continue;
481			mask = N_SET;
482		}
483
484		xioctl(sockfd, SIOCGIFFLAGS, &ifr);
485		selector = op->selector;
486		if (mask & SET_MASK)
487			ifr.ifr_flags |= selector;
488		else
489			ifr.ifr_flags &= ~selector;
490		xioctl(sockfd, SIOCSIFFLAGS, &ifr);
491	} /* while () */
492
493	if (ENABLE_FEATURE_CLEAN_UP)
494		close(sockfd);
495	return 0;
496}
497
498#if ENABLE_FEATURE_IFCONFIG_HW
499/* Input an Ethernet address and convert to binary. */
500static int in_ether(const char *bufp, struct sockaddr *sap)
501{
502	char *ptr;
503	int i, j;
504	unsigned char val;
505	unsigned char c;
506
507	sap->sa_family = ARPHRD_ETHER;
508	ptr = sap->sa_data;
509
510	i = 0;
511	do {
512		j = val = 0;
513
514		/* We might get a semicolon here - not required. */
515		if (i && (*bufp == ':')) {
516			bufp++;
517		}
518
519		do {
520			c = *bufp;
521			if (((unsigned char)(c - '0')) <= 9) {
522				c -= '0';
523			} else if (((unsigned char)((c|0x20) - 'a')) <= 5) {
524				c = (c|0x20) - ('a'-10);
525			} else if (j && (c == ':' || c == 0)) {
526				break;
527			} else {
528				return -1;
529			}
530			++bufp;
531			val <<= 4;
532			val += c;
533		} while (++j < 2);
534		*ptr++ = val;
535	} while (++i < ETH_ALEN);
536
537	return *bufp; /* Error if we don't end at end of string. */
538}
539#endif
540