1/* ifconfig
2 *
3 * Similar to the standard Unix ifconfig, but with only the necessary
4 * parts for AF_INET, and without any printing of if info (for now).
5 *
6 * Bjorn Wesen, Axis Communications AB
7 *
8 *
9 * Authors of the original ifconfig was:
10 *              Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
11 *
12 * This program is free software; you can redistribute it
13 * and/or  modify it under  the terms of  the GNU General
14 * Public  License as  published  by  the  Free  Software
15 * Foundation;  either  version 2 of the License, or  (at
16 * your option) any later version.
17 *
18 * $Id: ifconfig.c,v 1.1.1.1 2008/10/15 03:28:32 james26_jang Exp $
19 *
20 */
21
22/*
23 * Heavily modified by Manuel Novoa III       Mar 6, 2001
24 *
25 * From initial port to busybox, removed most of the redundancy by
26 * converting to a table-driven approach.  Added several (optional)
27 * args missing from initial port.
28 *
29 * Still missing:  media, tunnel.
30 */
31
32#include <stdio.h>
33#include <stdlib.h>
34#include <string.h>   // strcmp and friends
35#include <ctype.h>    // isdigit and friends
36#include <stddef.h>				/* offsetof */
37#include <sys/types.h>
38#include <sys/socket.h>
39#include <sys/ioctl.h>
40#include <netinet/in.h>
41#include <arpa/inet.h>
42#include <net/if.h>
43#include <net/if_arp.h>
44#include <linux/if_ether.h>
45#include "busybox.h"
46
47#ifdef BB_FEATURE_IFCONFIG_SLIP
48#include <linux/if_slip.h>
49#endif
50
51/* I don't know if this is needed for busybox or not.  Anyone? */
52#define QUESTIONABLE_ALIAS_CASE
53
54
55/* Defines for glibc2.0 users. */
56#ifndef SIOCSIFTXQLEN
57#define SIOCSIFTXQLEN      0x8943
58#define SIOCGIFTXQLEN      0x8942
59#endif
60
61/* ifr_qlen is ifru_ivalue, but it isn't present in 2.0 kernel headers */
62#ifndef ifr_qlen
63#define ifr_qlen        ifr_ifru.ifru_mtu
64#endif
65
66#ifndef IFF_DYNAMIC
67#define IFF_DYNAMIC     0x8000  /* dialup device with changing addresses */
68#endif
69
70/*
71 * Here are the bit masks for the "flags" member of struct options below.
72 * N_ signifies no arg prefix; M_ signifies arg prefixed by '-'.
73 * CLR clears the flag; SET sets the flag; ARG signifies (optional) arg.
74 */
75#define N_CLR            0x01
76#define M_CLR            0x02
77#define N_SET            0x04
78#define M_SET            0x08
79#define N_ARG            0x10
80#define M_ARG            0x20
81
82#define M_MASK           (M_CLR | M_SET | M_ARG)
83#define N_MASK           (N_CLR | N_SET | N_ARG)
84#define SET_MASK         (N_SET | M_SET)
85#define CLR_MASK         (N_CLR | M_CLR)
86#define SET_CLR_MASK     (SET_MASK | CLR_MASK)
87#define ARG_MASK         (M_ARG | N_ARG)
88
89/*
90 * Here are the bit masks for the "arg_flags" member of struct options below.
91 */
92
93/*
94 * cast type:
95 *   00 int
96 *   01 char *
97 *   02 HOST_COPY in_ether
98 *   03 HOST_COPY INET_resolve
99 */
100#define A_CAST_TYPE      0x03
101/*
102 * map type:
103 *   00 not a map type (mem_start, io_addr, irq)
104 *   04 memstart (unsigned long)
105 *   08 io_addr  (unsigned short)
106 *   0C irq      (unsigned char)
107 */
108#define A_MAP_TYPE       0x0C
109#define A_ARG_REQ        0x10	/* Set if an arg is required. */
110#define A_NETMASK        0x20	/* Set if netmask (check for multiple sets). */
111#define A_SET_AFTER      0x40	/* Set a flag at the end. */
112#define A_COLON_CHK      0x80	/* Is this needed?  See below. */
113#define A_HOSTNAME      0x100	/* Set if it is ip addr. */
114#define A_BROADCAST     0x200	/* Set if it is broadcast addr. */
115
116/*
117 * These defines are for dealing with the A_CAST_TYPE field.
118 */
119#define A_CAST_CHAR_PTR  0x01
120#define A_CAST_RESOLVE   0x01
121#define A_CAST_HOST_COPY 0x02
122#define A_CAST_HOST_COPY_IN_ETHER    A_CAST_HOST_COPY
123#define A_CAST_HOST_COPY_RESOLVE     (A_CAST_HOST_COPY | A_CAST_RESOLVE)
124
125/*
126 * These defines are for dealing with the A_MAP_TYPE field.
127 */
128#define A_MAP_ULONG      0x04	/* memstart */
129#define A_MAP_USHORT     0x08	/* io_addr */
130#define A_MAP_UCHAR      0x0C	/* irq */
131
132/*
133 * Define the bit masks signifying which operations to perform for each arg.
134 */
135
136#define ARG_METRIC       (A_ARG_REQ /*| A_CAST_INT*/)
137#define ARG_MTU          (A_ARG_REQ /*| A_CAST_INT*/)
138#define ARG_TXQUEUELEN   (A_ARG_REQ /*| A_CAST_INT*/)
139#define ARG_MEM_START    (A_ARG_REQ | A_MAP_ULONG)
140#define ARG_IO_ADDR      (A_ARG_REQ | A_MAP_USHORT)
141#define ARG_IRQ          (A_ARG_REQ | A_MAP_UCHAR)
142#define ARG_DSTADDR      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE)
143#define ARG_NETMASK      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_NETMASK)
144#define ARG_BROADCAST    (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_BROADCAST)
145#define ARG_HW           (A_ARG_REQ | A_CAST_HOST_COPY_IN_ETHER)
146#define ARG_POINTOPOINT  (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
147#define ARG_KEEPALIVE    (A_ARG_REQ | A_CAST_CHAR_PTR)
148#define ARG_OUTFILL      (A_ARG_REQ | A_CAST_CHAR_PTR)
149#define ARG_HOSTNAME     (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_COLON_CHK | A_HOSTNAME)
150
151
152/*
153 * Set up the tables.  Warning!  They must have corresponding order!
154 */
155
156struct arg1opt {
157	const char *name;
158	unsigned short selector;
159	unsigned short ifr_offset;
160};
161
162struct options {
163	const char *name;
164	const unsigned char flags;
165	const unsigned int arg_flags;
166	const unsigned short selector;
167};
168
169#define ifreq_offsetof(x)  offsetof(struct ifreq, x)
170
171static const struct arg1opt Arg1Opt[] = {
172	{"SIOCSIFMETRIC",  SIOCSIFMETRIC,  ifreq_offsetof(ifr_metric)},
173	{"SIOCSIFMTU",     SIOCSIFMTU,     ifreq_offsetof(ifr_mtu)},
174	{"SIOCSIFTXQLEN",  SIOCSIFTXQLEN,  ifreq_offsetof(ifr_qlen)},
175	{"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
176	{"SIOCSIFNETMASK", SIOCSIFNETMASK, ifreq_offsetof(ifr_netmask)},
177	{"SIOCSIFBRDADDR", SIOCSIFBRDADDR, ifreq_offsetof(ifr_broadaddr)},
178#ifdef BB_FEATURE_IFCONFIG_HW
179	{"SIOCSIFHWADDR",  SIOCSIFHWADDR,  ifreq_offsetof(ifr_hwaddr)},
180#endif
181	{"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
182#ifdef SIOCSKEEPALIVE
183	{"SIOCSKEEPALIVE", SIOCSKEEPALIVE, ifreq_offsetof(ifr_data)},
184#endif
185#ifdef SIOCSOUTFILL
186	{"SIOCSOUTFILL",   SIOCSOUTFILL,   ifreq_offsetof(ifr_data)},
187#endif
188#ifdef BB_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
189	{"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.mem_start)},
190	{"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.base_addr)},
191	{"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.irq)},
192#endif
193	/* Last entry if for unmatched (possibly hostname) arg. */
194	{"SIOCSIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr)},
195};
196
197static const struct options OptArray[] = {
198	{"metric",       N_ARG,         ARG_METRIC,      0},
199    {"mtu",          N_ARG,         ARG_MTU,         0},
200	{"txqueuelen",   N_ARG,         ARG_TXQUEUELEN,  0},
201	{"dstaddr",      N_ARG,         ARG_DSTADDR,     0},
202	{"netmask",      N_ARG,         ARG_NETMASK,     0},
203	{"broadcast",    N_ARG | M_CLR, ARG_BROADCAST,   IFF_BROADCAST},
204#ifdef BB_FEATURE_IFCONFIG_HW
205	{"hw",           N_ARG,         ARG_HW,          0},
206#endif
207	{"pointopoint",  N_ARG | M_CLR, ARG_POINTOPOINT, IFF_POINTOPOINT},
208#ifdef SIOCSKEEPALIVE
209	{"keepalive",    N_ARG,         ARG_KEEPALIVE,   0},
210#endif
211#ifdef SIOCSOUTFILL
212	{"outfill",      N_ARG,         ARG_OUTFILL,     0},
213#endif
214#ifdef BB_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
215	{"mem_start",    N_ARG,         ARG_MEM_START,   0},
216	{"io_addr",      N_ARG,         ARG_IO_ADDR,     0},
217	{"irq",          N_ARG,         ARG_IRQ,         0},
218#endif
219	{"arp",          N_CLR | M_SET, 0,               IFF_NOARP},
220	{"trailers",     N_CLR | M_SET, 0,               IFF_NOTRAILERS},
221	{"promisc",      N_SET | M_CLR, 0,               IFF_PROMISC},
222	{"multicast",    N_SET | M_CLR, 0,               IFF_MULTICAST},
223	{"allmulti",     N_SET | M_CLR, 0,               IFF_ALLMULTI},
224	{"dynamic",      N_SET | M_CLR, 0,               IFF_DYNAMIC},
225	{"up",           N_SET        , 0,               (IFF_UP | IFF_RUNNING)},
226	{"down",         N_CLR        , 0,               IFF_UP},
227	{ NULL,          0,             ARG_HOSTNAME,    (IFF_UP | IFF_RUNNING)}
228};
229
230/*
231 * A couple of prototypes.
232 */
233
234#ifdef BB_FEATURE_IFCONFIG_HW
235static int in_ether(char *bufp, struct sockaddr *sap);
236#endif
237
238#ifdef BB_FEATURE_IFCONFIG_STATUS
239extern int interface_opt_a;
240extern int display_interfaces(char *ifname);
241#endif
242
243/*
244 * Our main function.
245 */
246
247int ifconfig_main(int argc, char **argv)
248{
249	struct ifreq ifr;
250	struct sockaddr_in sai;
251	struct sockaddr_in sai_hostname, sai_netmask;
252#ifdef BB_FEATURE_IFCONFIG_HW
253	struct sockaddr sa;
254#endif
255	const struct arg1opt *a1op;
256	const struct options *op;
257	int sockfd;  /* socket fd we use to manipulate stuff with */
258	int goterr;
259	int selector;
260	char *p;
261	char host[128];
262	unsigned int mask;
263	unsigned int did_flags;
264
265	goterr = 0;
266	did_flags = 0;
267
268	/* skip argv[0] */
269	++argv;
270	--argc;
271
272#ifdef BB_FEATURE_IFCONFIG_STATUS
273	if ((argc > 0) && (strcmp(*argv,"-a") == 0)) {
274		interface_opt_a = 1;
275		--argc;
276		++argv;
277	}
278#endif
279
280	if(argc <= 1) {
281#ifdef BB_FEATURE_IFCONFIG_STATUS
282		return display_interfaces(argc ? *argv : NULL);
283#else
284		error_msg_and_die( "ifconfig was not compiled with interface status display support.");
285#endif
286	}
287
288	/* Create a channel to the NET kernel. */
289	if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
290		perror_msg_and_die("socket");
291	}
292
293	/* get interface name */
294	safe_strncpy(ifr.ifr_name, *argv, IFNAMSIZ);
295
296	/* Process the remaining arguments. */
297	while (*++argv != (char *) NULL) {
298		p = *argv;
299		mask = N_MASK;
300		if (*p == '-') {		/* If the arg starts with '-'... */
301			++p;				/*    advance past it and */
302			mask = M_MASK;		/*    set the appropriate mask. */
303		}
304		for (op = OptArray ; op->name ; op++) {	/* Find table entry. */
305			if (strcmp(p,op->name) == 0) { /* If name matches... */
306				if ((mask &= op->flags)) { /* set the mask and go. */
307				    goto FOUND_ARG;;
308				}
309				/* If we get here, there was a valid arg with an */
310				/* invalid '-' prefix. */
311				++goterr;
312				goto LOOP;
313			}
314		}
315
316		/* We fell through, so treat as possible hostname. */
317		a1op = Arg1Opt + (sizeof(Arg1Opt) / sizeof(Arg1Opt[0])) - 1;
318		mask = op->arg_flags;
319		goto HOSTNAME;
320
321	FOUND_ARG:
322		if (mask & ARG_MASK) {
323			mask = op->arg_flags;
324			a1op = Arg1Opt + (op - OptArray);
325			if (mask & A_NETMASK & did_flags) {
326				show_usage();
327			}
328			if (*++argv == NULL) {
329				if (mask & A_ARG_REQ) {
330					show_usage();
331				} else {
332					--argv;
333					mask &= A_SET_AFTER; /* just for broadcast */
334				}
335			} else {			/* got an arg so process it */
336			HOSTNAME:
337				did_flags |= (mask & (A_NETMASK|A_HOSTNAME));
338				if (mask & A_CAST_HOST_COPY) {
339#ifdef BB_FEATURE_IFCONFIG_HW
340					if (mask & A_CAST_RESOLVE) {
341#endif
342						safe_strncpy(host, *argv, (sizeof host));
343						sai.sin_family = AF_INET;
344						sai.sin_port = 0;
345						if (!strcmp(host, "default")) {
346							/* Default is special, meaning 0.0.0.0. */
347							sai.sin_addr.s_addr = INADDR_ANY;
348						} else if ((!strcmp(host, "+")) && (mask & A_BROADCAST) &&
349								 (did_flags & (A_NETMASK|A_HOSTNAME))) {
350							/* + is special, meaning broadcast is derived. */
351							sai.sin_addr.s_addr = (~sai_netmask.sin_addr.s_addr) |
352								(sai_hostname.sin_addr.s_addr & sai_netmask.sin_addr.s_addr);
353						} else if (inet_aton(host, &sai.sin_addr) == 0) {
354							/* It's not a dotted quad. */
355							++goterr;
356							continue;
357						}
358						if(mask & A_HOSTNAME)
359							sai_hostname = sai;
360						if(mask & A_NETMASK)
361							sai_netmask = sai;
362						p = (char *) &sai;
363#ifdef BB_FEATURE_IFCONFIG_HW
364					} else { /* A_CAST_HOST_COPY_IN_ETHER */
365						/* This is the "hw" arg case. */
366						if (strcmp("ether", *argv) || (*++argv == NULL)) {
367							show_usage();
368						}
369						safe_strncpy(host, *argv, (sizeof host));
370						if (in_ether(host, &sa)) {
371							fprintf(stderr, "invalid hw-addr %s\n", host);
372							++goterr;
373							continue;
374						}
375						p = (char *) &sa;
376					}
377#endif
378					memcpy((((char *)(&ifr)) + a1op->ifr_offset),
379						   p, sizeof(struct sockaddr));
380				} else {
381					unsigned int i = strtoul(*argv,NULL,0);
382					p = ((char *)(&ifr)) + a1op->ifr_offset;
383#ifdef BB_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
384					if (mask & A_MAP_TYPE) {
385						if (ioctl(sockfd, SIOCGIFMAP, &ifr) < 0) {
386							++goterr;
387							continue;
388						}
389						if ((mask & A_MAP_UCHAR) == A_MAP_UCHAR) {
390							*((unsigned char *) p) = i;
391						} else if (mask & A_MAP_USHORT) {
392							*((unsigned short *) p) = i;
393						} else {
394							*((unsigned long *) p) = i;
395						}
396					} else
397#endif
398					if (mask & A_CAST_CHAR_PTR) {
399						*((caddr_t *) p) = (caddr_t) i;
400					} else { /* A_CAST_INT */
401						*((int *) p) = i;
402					}
403				}
404
405				if (ioctl(sockfd, a1op->selector, &ifr) < 0) {
406					perror(a1op->name);
407					++goterr;
408					continue;
409				}
410
411#ifdef QUESTIONABLE_ALIAS_CASE
412				if (mask & A_COLON_CHK) {
413					/*
414					 * Don't do the set_flag() if the address is an alias with
415					 * a - at the end, since it's deleted already! - Roman
416					 *
417					 * Should really use regex.h here, not sure though how well
418					 * it'll go with the cross-platform support etc.
419					 */
420					char *ptr;
421					short int found_colon = 0;
422					for (ptr = ifr.ifr_name; *ptr; ptr++ ) {
423						if (*ptr == ':') {
424							found_colon++;
425						}
426					}
427
428					if (found_colon && *(ptr - 1) == '-') {
429						continue;
430					}
431				}
432#endif
433			}
434			if (!(mask & A_SET_AFTER)) {
435				continue;
436			}
437			mask = N_SET;
438		}
439
440		if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) < 0) {
441			perror("SIOCGIFFLAGS");
442			++goterr;
443		} else {
444			selector = op->selector;
445			if (mask & SET_MASK) {
446				ifr.ifr_flags |= selector;
447			} else {
448				ifr.ifr_flags &= ~selector;
449			}
450			if (ioctl(sockfd, SIOCSIFFLAGS, &ifr) < 0) {
451				perror("SIOCSIFFLAGS");
452				++goterr;
453			}
454		}
455	LOOP:
456	} /* end of while-loop */
457
458	return goterr;
459}
460
461#ifdef BB_FEATURE_IFCONFIG_HW
462/* Input an Ethernet address and convert to binary. */
463static int
464in_ether(char *bufp, struct sockaddr *sap)
465{
466	unsigned char *ptr;
467	int i, j;
468	unsigned char val;
469	unsigned char c;
470
471	sap->sa_family = ARPHRD_ETHER;
472	ptr = sap->sa_data;
473
474	for (i = 0 ; i < ETH_ALEN ; i++) {
475		val = 0;
476
477		/* We might get a semicolon here - not required. */
478		if (i && (*bufp == ':')) {
479			bufp++;
480		}
481
482		for (j=0 ; j<2 ; j++) {
483			c = *bufp;
484			if (c >= '0' && c <= '9') {
485				c -= '0';
486			} else if (c >= 'a' && c <= 'f') {
487				c -= ('a' - 10);
488			} else if (c >= 'A' && c <= 'F') {
489				c -= ('A' - 10);
490			} else if (j && (c == ':' || c == 0)) {
491				break;
492			} else {
493				return -1;
494			}
495			++bufp;
496			val <<= 4;
497			val += c;
498		}
499		*ptr++ = val;
500	}
501
502	return (int) (*bufp);		/* Error if we don't end at end of string. */
503}
504#endif
505