networking/ifconfig.c - codeaurora/busybox - Gitiles

 /* ifconfig
  *
  * Similar to the standard Unix ifconfig, but with only the necessary
  * parts for AF_INET, and without any printing of if info (for now).
  *
  * Bjorn Wesen, Axis Communications AB
  *
  *
  * Authors of the original ifconfig was:
  *              Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
  *
  * This program is free software; you can redistribute it
  * and/or  modify it under  the terms of  the GNU General
  * Public  License as  published  by  the  Free  Software
  * Foundation;  either  version 2 of the License, or  (at
  * your option) any later version.
  *
  * $Id: ifconfig.c,v 1.22 2003/01/14 08:54:07 andersen Exp $
  *
  */

 /*
  * Heavily modified by Manuel Novoa III       Mar 6, 2001
  *
  * From initial port to busybox, removed most of the redundancy by
  * converting to a table-driven approach.  Added several (optional)
  * args missing from initial port.
  *
  * Still missing:  media, tunnel.
  *
  * 2002-04-20
  * IPV6 support added by Bart Visscher <magick@linux-fan.com>
  */

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>		/* strcmp and friends */
 #include <ctype.h>		/* isdigit and friends */
 #include <stddef.h>		/* offsetof */
 #include <sys/ioctl.h>
 #include <net/if.h>
 #include <net/if_arp.h>
 #include <netinet/in.h>
 #if __GLIBC__ >=2 && __GLIBC_MINOR >= 1
 #include <netpacket/packet.h>
 #include <net/ethernet.h>
 #else
 #include <asm/types.h>
 #include <linux/if_ether.h>
 #endif
 #include "inet_common.h"
 #include "busybox.h"

 #ifdef CONFIG_FEATURE_IFCONFIG_SLIP
 # include <net/if_slip.h>
 #endif

 /* I don't know if this is needed for busybox or not.  Anyone? */
 #define QUESTIONABLE_ALIAS_CASE


 /* Defines for glibc2.0 users. */
 #ifndef SIOCSIFTXQLEN
 # define SIOCSIFTXQLEN      0x8943
 # define SIOCGIFTXQLEN      0x8942
 #endif

 /* ifr_qlen is ifru_ivalue, but it isn't present in 2.0 kernel headers */
 #ifndef ifr_qlen
 # define ifr_qlen        ifr_ifru.ifru_mtu
 #endif

 #ifndef IFF_DYNAMIC
 # define IFF_DYNAMIC     0x8000	/* dialup device with changing addresses */
 #endif

 #ifdef CONFIG_FEATURE_IPV6
 struct in6_ifreq {
 	struct in6_addr ifr6_addr;
 	uint32_t ifr6_prefixlen;
 	int ifr6_ifindex;
 };
 #endif

 /*
  * Here are the bit masks for the "flags" member of struct options below.
  * N_ signifies no arg prefix; M_ signifies arg prefixed by '-'.
  * CLR clears the flag; SET sets the flag; ARG signifies (optional) arg.
  */
 #define N_CLR            0x01
 #define M_CLR            0x02
 #define N_SET            0x04
 #define M_SET            0x08
 #define N_ARG            0x10
 #define M_ARG            0x20

 #define M_MASK           (M_CLR | M_SET | M_ARG)
 #define N_MASK           (N_CLR | N_SET | N_ARG)
 #define SET_MASK         (N_SET | M_SET)
 #define CLR_MASK         (N_CLR | M_CLR)
 #define SET_CLR_MASK     (SET_MASK | CLR_MASK)
 #define ARG_MASK         (M_ARG | N_ARG)

 /*
  * Here are the bit masks for the "arg_flags" member of struct options below.
  */

 /*
  * cast type:
  *   00 int
  *   01 char *
  *   02 HOST_COPY in_ether
  *   03 HOST_COPY INET_resolve
  */
 #define A_CAST_TYPE      0x03
 /*
  * map type:
  *   00 not a map type (mem_start, io_addr, irq)
  *   04 memstart (unsigned long)
  *   08 io_addr  (unsigned short)
  *   0C irq      (unsigned char)
  */
 #define A_MAP_TYPE       0x0C
 #define A_ARG_REQ        0x10	/* Set if an arg is required. */
 #define A_NETMASK        0x20	/* Set if netmask (check for multiple sets). */
 #define A_SET_AFTER      0x40	/* Set a flag at the end. */
 #define A_COLON_CHK      0x80	/* Is this needed?  See below. */
 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 #define A_HOSTNAME      0x100	/* Set if it is ip addr. */
 #define A_BROADCAST     0x200	/* Set if it is broadcast addr. */
 #else
 #define A_HOSTNAME          0
 #define A_BROADCAST         0
 #endif

 /*
  * These defines are for dealing with the A_CAST_TYPE field.
  */
 #define A_CAST_CHAR_PTR  0x01
 #define A_CAST_RESOLVE   0x01
 #define A_CAST_HOST_COPY 0x02
 #define A_CAST_HOST_COPY_IN_ETHER    A_CAST_HOST_COPY
 #define A_CAST_HOST_COPY_RESOLVE     (A_CAST_HOST_COPY | A_CAST_RESOLVE)

 /*
  * These defines are for dealing with the A_MAP_TYPE field.
  */
 #define A_MAP_ULONG      0x04	/* memstart */
 #define A_MAP_USHORT     0x08	/* io_addr */
 #define A_MAP_UCHAR      0x0C	/* irq */

 /*
  * Define the bit masks signifying which operations to perform for each arg.
  */

 #define ARG_METRIC       (A_ARG_REQ /*| A_CAST_INT*/)
 #define ARG_MTU          (A_ARG_REQ /*| A_CAST_INT*/)
 #define ARG_TXQUEUELEN   (A_ARG_REQ /*| A_CAST_INT*/)
 #define ARG_MEM_START    (A_ARG_REQ | A_MAP_ULONG)
 #define ARG_IO_ADDR      (A_ARG_REQ | A_MAP_ULONG)
 #define ARG_IRQ          (A_ARG_REQ | A_MAP_UCHAR)
 #define ARG_DSTADDR      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE)
 #define ARG_NETMASK      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_NETMASK)
 #define ARG_BROADCAST    (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_BROADCAST)
 #define ARG_HW           (A_ARG_REQ | A_CAST_HOST_COPY_IN_ETHER)
 #define ARG_POINTOPOINT  (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
 #define ARG_KEEPALIVE    (A_ARG_REQ | A_CAST_CHAR_PTR)
 #define ARG_OUTFILL      (A_ARG_REQ | A_CAST_CHAR_PTR)
 #define ARG_HOSTNAME     (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_COLON_CHK | A_HOSTNAME)
 #define ARG_ADD_DEL      (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)


 /*
  * Set up the tables.  Warning!  They must have corresponding order!
  */

 struct arg1opt {
 	const char *name;
 	unsigned short selector;
 	unsigned short ifr_offset;
 };

 struct options {
 	const char *name;
 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 	const unsigned int flags:6;
 	const unsigned int arg_flags:10;
 #else
 	const unsigned char flags;
 	const unsigned char arg_flags;
 #endif
 	const unsigned short selector;
 };

 #define ifreq_offsetof(x)  offsetof(struct ifreq, x)

 static const struct arg1opt Arg1Opt[] = {
 	{"SIOCSIFMETRIC",  SIOCSIFMETRIC,  ifreq_offsetof(ifr_metric)},
 	{"SIOCSIFMTU",     SIOCSIFMTU,     ifreq_offsetof(ifr_mtu)},
 	{"SIOCSIFTXQLEN",  SIOCSIFTXQLEN,  ifreq_offsetof(ifr_qlen)},
 	{"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
 	{"SIOCSIFNETMASK", SIOCSIFNETMASK, ifreq_offsetof(ifr_netmask)},
 	{"SIOCSIFBRDADDR", SIOCSIFBRDADDR, ifreq_offsetof(ifr_broadaddr)},
 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 	{"SIOCSIFHWADDR",  SIOCSIFHWADDR,  ifreq_offsetof(ifr_hwaddr)},
 #endif
 	{"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
 #ifdef SIOCSKEEPALIVE
 	{"SIOCSKEEPALIVE", SIOCSKEEPALIVE, ifreq_offsetof(ifr_data)},
 #endif
 #ifdef SIOCSOUTFILL
 	{"SIOCSOUTFILL",   SIOCSOUTFILL,   ifreq_offsetof(ifr_data)},
 #endif
 #ifdef CONFIG_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 	{"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.mem_start)},
 	{"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.base_addr)},
 	{"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.irq)},
 #endif
 	/* Last entry if for unmatched (possibly hostname) arg. */
 #ifdef CONFIG_FEATURE_IPV6
 	{"SIOCSIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr)}, /* IPv6 version ignores the offset */
 	{"SIOCDIFADDR",    SIOCDIFADDR,    ifreq_offsetof(ifr_addr)}, /* IPv6 version ignores the offset */
 #endif
 	{"SIOCSIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr)},
 };

 static const struct options OptArray[] = {
 	{"metric",      N_ARG,         ARG_METRIC,      0},
 	{"mtu",         N_ARG,         ARG_MTU,         0},
 	{"txqueuelen",  N_ARG,         ARG_TXQUEUELEN,  0},
 	{"dstaddr",     N_ARG,         ARG_DSTADDR,     0},
 	{"netmask",     N_ARG,         ARG_NETMASK,     0},
 	{"broadcast",   N_ARG | M_CLR, ARG_BROADCAST,   IFF_BROADCAST},
 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 	{"hw",          N_ARG, ARG_HW,                  0},
 #endif
 	{"pointopoint", N_ARG | M_CLR, ARG_POINTOPOINT, IFF_POINTOPOINT},
 #ifdef SIOCSKEEPALIVE
 	{"keepalive",   N_ARG,         ARG_KEEPALIVE,   0},
 #endif
 #ifdef SIOCSOUTFILL
 	{"outfill",     N_ARG,         ARG_OUTFILL,     0},
 #endif
 #ifdef CONFIG_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 	{"mem_start",   N_ARG,         ARG_MEM_START,   0},
 	{"io_addr",     N_ARG,         ARG_IO_ADDR,     0},
 	{"irq",         N_ARG,         ARG_IRQ,         0},
 #endif
 #ifdef CONFIG_FEATURE_IPV6
 	{"add",         N_ARG,         ARG_ADD_DEL,     0},
 	{"del",         N_ARG,         ARG_ADD_DEL,     0},
 #endif
 	{"arp",         N_CLR | M_SET, 0,               IFF_NOARP},
 	{"trailers",    N_CLR | M_SET, 0,               IFF_NOTRAILERS},
 	{"promisc",     N_SET | M_CLR, 0,               IFF_PROMISC},
 	{"multicast",   N_SET | M_CLR, 0,               IFF_MULTICAST},
 	{"allmulti",    N_SET | M_CLR, 0,               IFF_ALLMULTI},
 	{"dynamic",     N_SET | M_CLR, 0,               IFF_DYNAMIC},
 	{"up",          N_SET,         0,               (IFF_UP | IFF_RUNNING)},
 	{"down",        N_CLR,         0,               IFF_UP},
 	{NULL,          0,             ARG_HOSTNAME,    (IFF_UP | IFF_RUNNING)}
 };

 /*
  * A couple of prototypes.
  */

 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 static int in_ether(char *bufp, struct sockaddr *sap);
 #endif

 #ifdef CONFIG_FEATURE_IFCONFIG_STATUS
 extern int interface_opt_a;
 extern int display_interfaces(char *ifname);
 #endif

 /*
  * Our main function.
  */

 int ifconfig_main(int argc, char **argv)
 {
 	struct ifreq ifr;
 	struct sockaddr_in sai;
 #ifdef CONFIG_FEATURE_IPV6
 	struct sockaddr_in6 sai6;
 #endif
 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 	struct sockaddr sa;
 #endif
 	const struct arg1opt *a1op;
 	const struct options *op;
 	int sockfd;			/* socket fd we use to manipulate stuff with */
 	int goterr;
 	int selector;
 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 	unsigned int mask;
 	unsigned int did_flags;
 	in_addr_t sai_hostname, sai_netmask;
 #else
 	unsigned char mask;
 	unsigned char did_flags;
 #endif
 	char *p;
 	char host[128];

 	goterr = 0;
 	did_flags = 0;

 	/* skip argv[0] */
 	++argv;
 	--argc;

 #ifdef CONFIG_FEATURE_IFCONFIG_STATUS
 	if ((argc > 0) && (((*argv)[0] == '-') && ((*argv)[1] == 'a') && !(*argv)[2])) {
 		interface_opt_a = 1;
 		--argc;
 		++argv;
 	}
 #endif

 	if (argc <= 1) {
 #ifdef CONFIG_FEATURE_IFCONFIG_STATUS
 		return display_interfaces(argc ? *argv : NULL);
 #else
 		error_msg_and_die
 			("ifconfig was not compiled with interface status display support.");
 #endif
 	}

 	/* Create a channel to the NET kernel. */
 	if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
 		perror_msg_and_die("socket");
 	}

 	/* get interface name */
 	safe_strncpy(ifr.ifr_name, *argv, IFNAMSIZ);

 	/* Process the remaining arguments. */
 	while (*++argv != (char *) NULL) {
 		p = *argv;
 		mask = N_MASK;
 		if (*p == '-') {	/* If the arg starts with '-'... */
 			++p;		/*    advance past it and */
 			mask = M_MASK;	/*    set the appropriate mask. */
 		}
 		for (op = OptArray; op->name; op++) {	/* Find table entry. */
 			if (strcmp(p, op->name) == 0) {	/* If name matches... */
 				if ((mask &= op->flags)) {	/* set the mask and go. */
 					goto FOUND_ARG;;
 				}
 				/* If we get here, there was a valid arg with an */
 				/* invalid '-' prefix. */
 				++goterr;
 				goto LOOP;
 			}
 		}

 		/* We fell through, so treat as possible hostname. */
 		a1op = Arg1Opt + (sizeof(Arg1Opt) / sizeof(Arg1Opt[0])) - 1;
 		mask = op->arg_flags;
 		goto HOSTNAME;

 	  FOUND_ARG:
 		if (mask & ARG_MASK) {
 			mask = op->arg_flags;
 			a1op = Arg1Opt + (op - OptArray);
 			if (mask & A_NETMASK & did_flags) {
 				show_usage();
 			}
 			if (*++argv == NULL) {
 				if (mask & A_ARG_REQ) {
 					show_usage();
 				} else {
 					--argv;
 					mask &= A_SET_AFTER;	/* just for broadcast */
 				}
 			} else {	/* got an arg so process it */
 			  HOSTNAME:
 				did_flags |= (mask & (A_NETMASK|A_HOSTNAME));
 				if (mask & A_CAST_HOST_COPY) {
 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 					if (mask & A_CAST_RESOLVE) {
 #endif
 #ifdef CONFIG_FEATURE_IPV6
 						char *prefix;
 						int prefix_len = 0;
 #endif

 						safe_strncpy(host, *argv, (sizeof host));
 #ifdef CONFIG_FEATURE_IPV6
 						if ((prefix = strchr(host, '/'))) {
 							prefix_len = atol(prefix + 1);
 							if ((prefix_len < 0) || (prefix_len > 128)) {
 								++goterr;
 								goto LOOP;
 							}
 							*prefix = 0;
 						}
 #endif

 						sai.sin_family = AF_INET;
 						sai.sin_port = 0;
 						if (!strcmp(host, bb_INET_default)) {
 							/* Default is special, meaning 0.0.0.0. */
 							sai.sin_addr.s_addr = INADDR_ANY;
 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 						} else if (((host[0] == '+') && !host[1]) && (mask & A_BROADCAST) &&
 								   (did_flags & (A_NETMASK|A_HOSTNAME)) == (A_NETMASK|A_HOSTNAME)) {
 							/* + is special, meaning broadcast is derived. */
 							sai.sin_addr.s_addr = (~sai_netmask) | (sai_hostname & sai_netmask);
 #endif
 #ifdef CONFIG_FEATURE_IPV6
 						} else if (inet_pton(AF_INET6, host, &sai6.sin6_addr) > 0) {
 							int sockfd6;
 							struct in6_ifreq ifr6;

 							memcpy((char *) &ifr6.ifr6_addr,
 								   (char *) &sai6.sin6_addr,
 								   sizeof(struct in6_addr));

 							/* Create a channel to the NET kernel. */
 							if ((sockfd6 = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
 								perror_msg_and_die("socket6");
 							}
 							if (ioctl(sockfd6, SIOGIFINDEX, &ifr) < 0) {
 								perror("SIOGIFINDEX");
 								++goterr;
 								continue;
 							}
 							ifr6.ifr6_ifindex = ifr.ifr_ifindex;
 							ifr6.ifr6_prefixlen = prefix_len;
 							if (ioctl(sockfd6, a1op->selector, &ifr6) < 0) {
 								perror(a1op->name);
 								++goterr;
 							}
 							continue;
 #endif
 						} else if (inet_aton(host, &sai.sin_addr) == 0) {
 							/* It's not a dotted quad. */
 							++goterr;
 							continue;
 						}
 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 						if (mask & A_HOSTNAME) {
 							sai_hostname = sai.sin_addr.s_addr;
 						}
 						if (mask & A_NETMASK) {
 							sai_netmask = sai.sin_addr.s_addr;
 						}
 #endif
 						p = (char *) &sai;
 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 					} else {	/* A_CAST_HOST_COPY_IN_ETHER */
 						/* This is the "hw" arg case. */
 						if (strcmp("ether", *argv) || (*++argv == NULL)) {
 							show_usage();
 						}
 						safe_strncpy(host, *argv, (sizeof host));
 						if (in_ether(host, &sa)) {
 							error_msg("invalid hw-addr %s", host);
 							++goterr;
 							continue;
 						}
 						p = (char *) &sa;
 					}
 #endif
 					memcpy((((char *) (&ifr)) + a1op->ifr_offset),
 						   p, sizeof(struct sockaddr));
 				} else {
 					unsigned int i = strtoul(*argv, NULL, 0);

 					p = ((char *) (&ifr)) + a1op->ifr_offset;
 #ifdef CONFIG_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 					if (mask & A_MAP_TYPE) {
 						if (ioctl(sockfd, SIOCGIFMAP, &ifr) < 0) {
 							++goterr;
 							continue;
 						}
 						if ((mask & A_MAP_UCHAR) == A_MAP_UCHAR) {
 							*((unsigned char *) p) = i;
 						} else if (mask & A_MAP_USHORT) {
 							*((unsigned short *) p) = i;
 						} else {
 							*((unsigned long *) p) = i;
 						}
 					} else
 #endif
 					if (mask & A_CAST_CHAR_PTR) {
 						*((caddr_t *) p) = (caddr_t) i;
 					} else {	/* A_CAST_INT */
 						*((int *) p) = i;
 					}
 				}

 				if (ioctl(sockfd, a1op->selector, &ifr) < 0) {
 					perror(a1op->name);
 					++goterr;
 					continue;
 				}
 #ifdef QUESTIONABLE_ALIAS_CASE
 				if (mask & A_COLON_CHK) {
 					/*
 					 * Don't do the set_flag() if the address is an alias with
 					 * a - at the end, since it's deleted already! - Roman
 					 *
 					 * Should really use regex.h here, not sure though how well
 					 * it'll go with the cross-platform support etc.
 					 */
 					char *ptr;
 					short int found_colon = 0;

 					for (ptr = ifr.ifr_name; *ptr; ptr++) {
 						if (*ptr == ':') {
 							found_colon++;
 						}
 					}

 					if (found_colon && *(ptr - 1) == '-') {
 						continue;
 					}
 				}
 #endif
 			}
 			if (!(mask & A_SET_AFTER)) {
 				continue;
 			}
 			mask = N_SET;
 		}

 		if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) < 0) {
 			perror("SIOCGIFFLAGS");
 			++goterr;
 		} else {
 			selector = op->selector;
 			if (mask & SET_MASK) {
 				ifr.ifr_flags |= selector;
 			} else {
 				ifr.ifr_flags &= ~selector;
 			}
 			if (ioctl(sockfd, SIOCSIFFLAGS, &ifr) < 0) {
 				perror("SIOCSIFFLAGS");
 				++goterr;
 			}
 		}
 	  LOOP:
 		continue;
 	}					/* end of while-loop */

 	return goterr;
 }

 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 /* Input an Ethernet address and convert to binary. */
 static int in_ether(char *bufp, struct sockaddr *sap)
 {
 	unsigned char *ptr;
 	int i, j;
 	unsigned char val;
 	unsigned char c;

 	sap->sa_family = ARPHRD_ETHER;
 	ptr = sap->sa_data;

 	i = 0;
 	do {
 		j = val = 0;

 		/* We might get a semicolon here - not required. */
 		if (i && (*bufp == ':')) {
 			bufp++;
 		}

 		do {
 			c = *bufp;
 			if (((unsigned char)(c - '0')) <= 9) {
 				c -= '0';
 			} else if (((unsigned char)((c|0x20) - 'a')) <= 5) {
 				c = (c|0x20) - ('a'-10);
 			} else if (j && (c == ':' || c == 0)) {
 				break;
 			} else {
 				return -1;
 			}
 			++bufp;
 			val <<= 4;
 			val += c;
 		} while (++j < 2);
 		*ptr++ = val;
 	} while (++i < ETH_ALEN);

 	return (int) (*bufp);	/* Error if we don't end at end of string. */
 }
 #endif
	/* ifconfig
	*
	* Similar to the standard Unix ifconfig, but with only the necessary
	* parts for AF_INET, and without any printing of if info (for now).
	*
	* Bjorn Wesen, Axis Communications AB
	*
	*
	* Authors of the original ifconfig was:
	* Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
	*
	* This program is free software; you can redistribute it
	* and/or modify it under the terms of the GNU General
	* Public License as published by the Free Software
	* Foundation; either version 2 of the License, or (at
	* your option) any later version.
	*
	* $Id: ifconfig.c,v 1.22 2003/01/14 08:54:07 andersen Exp $
	*
	*/

	/*
	* Heavily modified by Manuel Novoa III Mar 6, 2001
	*
	* From initial port to busybox, removed most of the redundancy by
	* converting to a table-driven approach. Added several (optional)
	* args missing from initial port.
	*
	* Still missing: media, tunnel.
	*
	* 2002-04-20
	* IPV6 support added by Bart Visscher <magick@linux-fan.com>
	*/

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h> /* strcmp and friends */
	#include <ctype.h> /* isdigit and friends */
	#include <stddef.h> /* offsetof */
	#include <sys/ioctl.h>
	#include <net/if.h>
	#include <net/if_arp.h>
	#include <netinet/in.h>
	#if __GLIBC__ >=2 && __GLIBC_MINOR >= 1
	#include <netpacket/packet.h>
	#include <net/ethernet.h>
	#else
	#include <asm/types.h>
	#include <linux/if_ether.h>
	#endif
	#include "inet_common.h"
	#include "busybox.h"

	#ifdef CONFIG_FEATURE_IFCONFIG_SLIP
	# include <net/if_slip.h>
	#endif

	/* I don't know if this is needed for busybox or not. Anyone? */
	#define QUESTIONABLE_ALIAS_CASE


	/* Defines for glibc2.0 users. */
	#ifndef SIOCSIFTXQLEN
	# define SIOCSIFTXQLEN 0x8943
	# define SIOCGIFTXQLEN 0x8942
	#endif

	/* ifr_qlen is ifru_ivalue, but it isn't present in 2.0 kernel headers */
	#ifndef ifr_qlen
	# define ifr_qlen ifr_ifru.ifru_mtu
	#endif

	#ifndef IFF_DYNAMIC
	# define IFF_DYNAMIC 0x8000 /* dialup device with changing addresses */
	#endif

	#ifdef CONFIG_FEATURE_IPV6
	struct in6_ifreq {
	struct in6_addr ifr6_addr;
	uint32_t ifr6_prefixlen;
	int ifr6_ifindex;
	};
	#endif

	/*
	* Here are the bit masks for the "flags" member of struct options below.
	* N_ signifies no arg prefix; M_ signifies arg prefixed by '-'.
	* CLR clears the flag; SET sets the flag; ARG signifies (optional) arg.
	*/
	#define N_CLR 0x01
	#define M_CLR 0x02
	#define N_SET 0x04
	#define M_SET 0x08
	#define N_ARG 0x10
	#define M_ARG 0x20

	#define M_MASK (M_CLR \| M_SET \| M_ARG)
	#define N_MASK (N_CLR \| N_SET \| N_ARG)
	#define SET_MASK (N_SET \| M_SET)
	#define CLR_MASK (N_CLR \| M_CLR)
	#define SET_CLR_MASK (SET_MASK \| CLR_MASK)
	#define ARG_MASK (M_ARG \| N_ARG)

	/*
	* Here are the bit masks for the "arg_flags" member of struct options below.
	*/

	/*
	* cast type:
	* 00 int
	* 01 char *
	* 02 HOST_COPY in_ether
	* 03 HOST_COPY INET_resolve
	*/
	#define A_CAST_TYPE 0x03
	/*
	* map type:
	* 00 not a map type (mem_start, io_addr, irq)
	* 04 memstart (unsigned long)
	* 08 io_addr (unsigned short)
	* 0C irq (unsigned char)
	*/
	#define A_MAP_TYPE 0x0C
	#define A_ARG_REQ 0x10 /* Set if an arg is required. */
	#define A_NETMASK 0x20 /* Set if netmask (check for multiple sets). */
	#define A_SET_AFTER 0x40 /* Set a flag at the end. */
	#define A_COLON_CHK 0x80 /* Is this needed? See below. */
	#ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
	#define A_HOSTNAME 0x100 /* Set if it is ip addr. */
	#define A_BROADCAST 0x200 /* Set if it is broadcast addr. */
	#else
	#define A_HOSTNAME 0
	#define A_BROADCAST 0
	#endif

	/*
	* These defines are for dealing with the A_CAST_TYPE field.
	*/
	#define A_CAST_CHAR_PTR 0x01
	#define A_CAST_RESOLVE 0x01
	#define A_CAST_HOST_COPY 0x02
	#define A_CAST_HOST_COPY_IN_ETHER A_CAST_HOST_COPY
	#define A_CAST_HOST_COPY_RESOLVE (A_CAST_HOST_COPY \| A_CAST_RESOLVE)

	/*
	* These defines are for dealing with the A_MAP_TYPE field.
	*/
	#define A_MAP_ULONG 0x04 /* memstart */
	#define A_MAP_USHORT 0x08 /* io_addr */
	#define A_MAP_UCHAR 0x0C /* irq */

	/*
	* Define the bit masks signifying which operations to perform for each arg.
	*/

	#define ARG_METRIC (A_ARG_REQ /\| A_CAST_INT/)
	#define ARG_MTU (A_ARG_REQ /\| A_CAST_INT/)
	#define ARG_TXQUEUELEN (A_ARG_REQ /\| A_CAST_INT/)
	#define ARG_MEM_START (A_ARG_REQ \| A_MAP_ULONG)
	#define ARG_IO_ADDR (A_ARG_REQ \| A_MAP_ULONG)
	#define ARG_IRQ (A_ARG_REQ \| A_MAP_UCHAR)
	#define ARG_DSTADDR (A_ARG_REQ \| A_CAST_HOST_COPY_RESOLVE)
	#define ARG_NETMASK (A_ARG_REQ \| A_CAST_HOST_COPY_RESOLVE \| A_NETMASK)
	#define ARG_BROADCAST (A_ARG_REQ \| A_CAST_HOST_COPY_RESOLVE \| A_SET_AFTER \| A_BROADCAST)
	#define ARG_HW (A_ARG_REQ \| A_CAST_HOST_COPY_IN_ETHER)
	#define ARG_POINTOPOINT (A_CAST_HOST_COPY_RESOLVE \| A_SET_AFTER)
	#define ARG_KEEPALIVE (A_ARG_REQ \| A_CAST_CHAR_PTR)
	#define ARG_OUTFILL (A_ARG_REQ \| A_CAST_CHAR_PTR)
	#define ARG_HOSTNAME (A_CAST_HOST_COPY_RESOLVE \| A_SET_AFTER \| A_COLON_CHK \| A_HOSTNAME)
	#define ARG_ADD_DEL (A_CAST_HOST_COPY_RESOLVE \| A_SET_AFTER)


	/*
	* Set up the tables. Warning! They must have corresponding order!
	*/

	struct arg1opt {
	const char *name;
	unsigned short selector;
	unsigned short ifr_offset;
	};

	struct options {
	const char *name;
	#ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
	const unsigned int flags:6;
	const unsigned int arg_flags:10;
	#else
	const unsigned char flags;
	const unsigned char arg_flags;
	#endif
	const unsigned short selector;
	};

	#define ifreq_offsetof(x) offsetof(struct ifreq, x)

	static const struct arg1opt Arg1Opt[] = {
	{"SIOCSIFMETRIC", SIOCSIFMETRIC, ifreq_offsetof(ifr_metric)},
	{"SIOCSIFMTU", SIOCSIFMTU, ifreq_offsetof(ifr_mtu)},
	{"SIOCSIFTXQLEN", SIOCSIFTXQLEN, ifreq_offsetof(ifr_qlen)},
	{"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
	{"SIOCSIFNETMASK", SIOCSIFNETMASK, ifreq_offsetof(ifr_netmask)},
	{"SIOCSIFBRDADDR", SIOCSIFBRDADDR, ifreq_offsetof(ifr_broadaddr)},
	#ifdef CONFIG_FEATURE_IFCONFIG_HW
	{"SIOCSIFHWADDR", SIOCSIFHWADDR, ifreq_offsetof(ifr_hwaddr)},
	#endif
	{"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
	#ifdef SIOCSKEEPALIVE
	{"SIOCSKEEPALIVE", SIOCSKEEPALIVE, ifreq_offsetof(ifr_data)},
	#endif
	#ifdef SIOCSOUTFILL
	{"SIOCSOUTFILL", SIOCSOUTFILL, ifreq_offsetof(ifr_data)},
	#endif
	#ifdef CONFIG_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
	{"SIOCSIFMAP", SIOCSIFMAP, ifreq_offsetof(ifr_map.mem_start)},
	{"SIOCSIFMAP", SIOCSIFMAP, ifreq_offsetof(ifr_map.base_addr)},
	{"SIOCSIFMAP", SIOCSIFMAP, ifreq_offsetof(ifr_map.irq)},
	#endif
	/* Last entry if for unmatched (possibly hostname) arg. */
	#ifdef CONFIG_FEATURE_IPV6
	{"SIOCSIFADDR", SIOCSIFADDR, ifreq_offsetof(ifr_addr)}, /* IPv6 version ignores the offset */
	{"SIOCDIFADDR", SIOCDIFADDR, ifreq_offsetof(ifr_addr)}, /* IPv6 version ignores the offset */
	#endif
	{"SIOCSIFADDR", SIOCSIFADDR, ifreq_offsetof(ifr_addr)},
	};

	static const struct options OptArray[] = {
	{"metric", N_ARG, ARG_METRIC, 0},
	{"mtu", N_ARG, ARG_MTU, 0},
	{"txqueuelen", N_ARG, ARG_TXQUEUELEN, 0},
	{"dstaddr", N_ARG, ARG_DSTADDR, 0},
	{"netmask", N_ARG, ARG_NETMASK, 0},
	{"broadcast", N_ARG \| M_CLR, ARG_BROADCAST, IFF_BROADCAST},
	#ifdef CONFIG_FEATURE_IFCONFIG_HW
	{"hw", N_ARG, ARG_HW, 0},
	#endif
	{"pointopoint", N_ARG \| M_CLR, ARG_POINTOPOINT, IFF_POINTOPOINT},
	#ifdef SIOCSKEEPALIVE
	{"keepalive", N_ARG, ARG_KEEPALIVE, 0},
	#endif
	#ifdef SIOCSOUTFILL
	{"outfill", N_ARG, ARG_OUTFILL, 0},
	#endif
	#ifdef CONFIG_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
	{"mem_start", N_ARG, ARG_MEM_START, 0},
	{"io_addr", N_ARG, ARG_IO_ADDR, 0},
	{"irq", N_ARG, ARG_IRQ, 0},
	#endif
	#ifdef CONFIG_FEATURE_IPV6
	{"add", N_ARG, ARG_ADD_DEL, 0},
	{"del", N_ARG, ARG_ADD_DEL, 0},
	#endif
	{"arp", N_CLR \| M_SET, 0, IFF_NOARP},
	{"trailers", N_CLR \| M_SET, 0, IFF_NOTRAILERS},
	{"promisc", N_SET \| M_CLR, 0, IFF_PROMISC},
	{"multicast", N_SET \| M_CLR, 0, IFF_MULTICAST},
	{"allmulti", N_SET \| M_CLR, 0, IFF_ALLMULTI},
	{"dynamic", N_SET \| M_CLR, 0, IFF_DYNAMIC},
	{"up", N_SET, 0, (IFF_UP \| IFF_RUNNING)},
	{"down", N_CLR, 0, IFF_UP},
	{NULL, 0, ARG_HOSTNAME, (IFF_UP \| IFF_RUNNING)}
	};

	/*
	* A couple of prototypes.
	*/

	#ifdef CONFIG_FEATURE_IFCONFIG_HW
	static int in_ether(char bufp, struct sockaddr sap);
	#endif

	#ifdef CONFIG_FEATURE_IFCONFIG_STATUS
	extern int interface_opt_a;
	extern int display_interfaces(char *ifname);
	#endif

	/*
	* Our main function.
	*/

	int ifconfig_main(int argc, char **argv)
	{
	struct ifreq ifr;
	struct sockaddr_in sai;
	#ifdef CONFIG_FEATURE_IPV6
	struct sockaddr_in6 sai6;
	#endif
	#ifdef CONFIG_FEATURE_IFCONFIG_HW
	struct sockaddr sa;
	#endif
	const struct arg1opt *a1op;
	const struct options *op;
	int sockfd; /* socket fd we use to manipulate stuff with */
	int goterr;
	int selector;
	#ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
	unsigned int mask;
	unsigned int did_flags;
	in_addr_t sai_hostname, sai_netmask;
	#else
	unsigned char mask;
	unsigned char did_flags;
	#endif
	char *p;
	char host[128];

	goterr = 0;
	did_flags = 0;

	/* skip argv[0] */
	++argv;
	--argc;

	#ifdef CONFIG_FEATURE_IFCONFIG_STATUS
	if ((argc > 0) && (((argv)[0] == '-') && ((argv)[1] == 'a') && !(*argv)[2])) {
	interface_opt_a = 1;
	--argc;
	++argv;
	}
	#endif

	if (argc <= 1) {
	#ifdef CONFIG_FEATURE_IFCONFIG_STATUS
	return display_interfaces(argc ? *argv : NULL);
	#else
	error_msg_and_die
	("ifconfig was not compiled with interface status display support.");
	#endif
	}

	/* Create a channel to the NET kernel. */
	if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
	perror_msg_and_die("socket");
	}

	/* get interface name */
	safe_strncpy(ifr.ifr_name, *argv, IFNAMSIZ);

	/* Process the remaining arguments. */
	while (++argv != (char ) NULL) {
	p = *argv;
	mask = N_MASK;
	if (p == '-') { / If the arg starts with '-'... */
	++p; /* advance past it and */
	mask = M_MASK; /* set the appropriate mask. */
	}
	for (op = OptArray; op->name; op++) { /* Find table entry. */
	if (strcmp(p, op->name) == 0) { /* If name matches... */
	if ((mask &= op->flags)) { /* set the mask and go. */
	goto FOUND_ARG;;
	}
	/* If we get here, there was a valid arg with an */
	/* invalid '-' prefix. */
	++goterr;
	goto LOOP;
	}
	}

	/* We fell through, so treat as possible hostname. */
	a1op = Arg1Opt + (sizeof(Arg1Opt) / sizeof(Arg1Opt[0])) - 1;
	mask = op->arg_flags;
	goto HOSTNAME;

	FOUND_ARG:
	if (mask & ARG_MASK) {
	mask = op->arg_flags;
	a1op = Arg1Opt + (op - OptArray);
	if (mask & A_NETMASK & did_flags) {
	show_usage();
	}
	if (*++argv == NULL) {
	if (mask & A_ARG_REQ) {
	show_usage();
	} else {
	--argv;
	mask &= A_SET_AFTER; /* just for broadcast */
	}
	} else { /* got an arg so process it */
	HOSTNAME:
	did_flags \|= (mask & (A_NETMASK\|A_HOSTNAME));
	if (mask & A_CAST_HOST_COPY) {
	#ifdef CONFIG_FEATURE_IFCONFIG_HW
	if (mask & A_CAST_RESOLVE) {
	#endif
	#ifdef CONFIG_FEATURE_IPV6
	char *prefix;
	int prefix_len = 0;
	#endif

	safe_strncpy(host, *argv, (sizeof host));
	#ifdef CONFIG_FEATURE_IPV6
	if ((prefix = strchr(host, '/'))) {
	prefix_len = atol(prefix + 1);
	if ((prefix_len < 0) \|\| (prefix_len > 128)) {
	++goterr;
	goto LOOP;
	}
	*prefix = 0;
	}
	#endif

	sai.sin_family = AF_INET;
	sai.sin_port = 0;
	if (!strcmp(host, bb_INET_default)) {
	/* Default is special, meaning 0.0.0.0. */
	sai.sin_addr.s_addr = INADDR_ANY;
	#ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
	} else if (((host[0] == '+') && !host[1]) && (mask & A_BROADCAST) &&
	(did_flags & (A_NETMASK\|A_HOSTNAME)) == (A_NETMASK\|A_HOSTNAME)) {
	/* + is special, meaning broadcast is derived. */
	sai.sin_addr.s_addr = (~sai_netmask) \| (sai_hostname & sai_netmask);
	#endif
	#ifdef CONFIG_FEATURE_IPV6
	} else if (inet_pton(AF_INET6, host, &sai6.sin6_addr) > 0) {
	int sockfd6;
	struct in6_ifreq ifr6;

	memcpy((char *) &ifr6.ifr6_addr,
	(char *) &sai6.sin6_addr,
	sizeof(struct in6_addr));

	/* Create a channel to the NET kernel. */
	if ((sockfd6 = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
	perror_msg_and_die("socket6");
	}
	if (ioctl(sockfd6, SIOGIFINDEX, &ifr) < 0) {
	perror("SIOGIFINDEX");
	++goterr;
	continue;
	}
	ifr6.ifr6_ifindex = ifr.ifr_ifindex;
	ifr6.ifr6_prefixlen = prefix_len;
	if (ioctl(sockfd6, a1op->selector, &ifr6) < 0) {
	perror(a1op->name);
	++goterr;
	}
	continue;
	#endif
	} else if (inet_aton(host, &sai.sin_addr) == 0) {
	/* It's not a dotted quad. */
	++goterr;
	continue;
	}
	#ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
	if (mask & A_HOSTNAME) {
	sai_hostname = sai.sin_addr.s_addr;
	}
	if (mask & A_NETMASK) {
	sai_netmask = sai.sin_addr.s_addr;
	}
	#endif
	p = (char *) &sai;
	#ifdef CONFIG_FEATURE_IFCONFIG_HW
	} else { /* A_CAST_HOST_COPY_IN_ETHER */
	/* This is the "hw" arg case. */
	if (strcmp("ether", argv) \|\| (++argv == NULL)) {
	show_usage();
	}
	safe_strncpy(host, *argv, (sizeof host));
	if (in_ether(host, &sa)) {
	error_msg("invalid hw-addr %s", host);
	++goterr;
	continue;
	}
	p = (char *) &sa;
	}
	#endif
	memcpy((((char *) (&ifr)) + a1op->ifr_offset),
	p, sizeof(struct sockaddr));
	} else {
	unsigned int i = strtoul(*argv, NULL, 0);

	p = ((char *) (&ifr)) + a1op->ifr_offset;
	#ifdef CONFIG_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
	if (mask & A_MAP_TYPE) {
	if (ioctl(sockfd, SIOCGIFMAP, &ifr) < 0) {
	++goterr;
	continue;
	}
	if ((mask & A_MAP_UCHAR) == A_MAP_UCHAR) {
	((unsigned char ) p) = i;
	} else if (mask & A_MAP_USHORT) {
	((unsigned short ) p) = i;
	} else {
	((unsigned long ) p) = i;
	}
	} else
	#endif
	if (mask & A_CAST_CHAR_PTR) {
	((caddr_t ) p) = (caddr_t) i;
	} else { /* A_CAST_INT */
	((int ) p) = i;
	}
	}

	if (ioctl(sockfd, a1op->selector, &ifr) < 0) {
	perror(a1op->name);
	++goterr;
	continue;
	}
	#ifdef QUESTIONABLE_ALIAS_CASE
	if (mask & A_COLON_CHK) {
	/*
	* Don't do the set_flag() if the address is an alias with
	* a - at the end, since it's deleted already! - Roman
	*
	* Should really use regex.h here, not sure though how well
	* it'll go with the cross-platform support etc.
	*/
	char *ptr;
	short int found_colon = 0;

	for (ptr = ifr.ifr_name; *ptr; ptr++) {
	if (*ptr == ':') {
	found_colon++;
	}
	}

	if (found_colon && *(ptr - 1) == '-') {
	continue;
	}
	}
	#endif
	}
	if (!(mask & A_SET_AFTER)) {
	continue;
	}
	mask = N_SET;
	}

	if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) < 0) {
	perror("SIOCGIFFLAGS");
	++goterr;
	} else {
	selector = op->selector;
	if (mask & SET_MASK) {
	ifr.ifr_flags \|= selector;
	} else {
	ifr.ifr_flags &= ~selector;
	}
	if (ioctl(sockfd, SIOCSIFFLAGS, &ifr) < 0) {
	perror("SIOCSIFFLAGS");
	++goterr;
	}
	}
	LOOP:
	continue;
	} /* end of while-loop */

	return goterr;
	}

	#ifdef CONFIG_FEATURE_IFCONFIG_HW
	/* Input an Ethernet address and convert to binary. */
	static int in_ether(char bufp, struct sockaddr sap)
	{
	unsigned char *ptr;
	int i, j;
	unsigned char val;
	unsigned char c;

	sap->sa_family = ARPHRD_ETHER;
	ptr = sap->sa_data;

	i = 0;
	do {
	j = val = 0;

	/* We might get a semicolon here - not required. */
	if (i && (*bufp == ':')) {
	bufp++;
	}

	do {
	c = *bufp;
	if (((unsigned char)(c - '0')) <= 9) {
	c -= '0';
	} else if (((unsigned char)((c\|0x20) - 'a')) <= 5) {
	c = (c\|0x20) - ('a'-10);
	} else if (j && (c == ':' \|\| c == 0)) {
	break;
	} else {
	return -1;
	}
	++bufp;
	val <<= 4;
	val += c;
	} while (++j < 2);
	*ptr++ = val;
	} while (++i < ETH_ALEN);

	return (int) (bufp); / Error if we don't end at end of string. */
	}
	#endif