ifconfig_main.c

自己改写的ifconfig代码程序

/* vi: set sw=4 ts=4: */
/* 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, <[e-mail]>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

/*
 * 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 <[e-mail]>
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>		/* strcmp and friends */
#include <ctype.h>		/* isdigit and friends */
#include <stddef.h>		/* offsetof */
#include <unistd.h>
#include <netdb.h>
#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 <sys/types.h>
#include <netinet/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


/*
 * 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_ARG_REQ | 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;
	int 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
		{"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

#endif
//add by hanke
char * safe_strncpy(char *dst, const char *src, size_t size);
int bb_xsocket(int domain, int type, int protocol);
static int in_ether(char *bufp, struct sockaddr *sap);

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

#define ENABLE_FEATURE_CLEAN_UP 1
/*
 * Our main function.
 */

int
main(int argc, char **argv)
{
	struct ifreq ifr;
	struct sockaddr_in sai;
//#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;
	unsigned int sai_hostname, sai_netmask;
//#else