hush/networking/ifconfig.c
Denis Vlasenko 9b49a5ed85 add -fvisibility=hidden to CC flags, mark XXX_main functions
EXTERNALLY_VISIBLE. 5% size reduction of libbusybox.so
2007-10-11 10:05:36 +00:00

541 lines
16 KiB
C

/* 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, <waltje@uwalt.nl.mugnet.org>
*
* 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 <magick@linux-fan.com>
*/
#include <net/if.h>
#include <net/if_arp.h>
#include <netinet/in.h>
#if defined(__GLIBC__) && __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 "libbb.h"
#if ENABLE_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
#if ENABLE_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. */
#if ENABLE_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;
#if ENABLE_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)},
#if ENABLE_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
#if ENABLE_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. */
#if ENABLE_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},
#if ENABLE_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
#if ENABLE_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
#if ENABLE_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.
*/
#if ENABLE_FEATURE_IFCONFIG_HW
static int in_ether(const char *bufp, struct sockaddr *sap);
#endif
/*
* Our main function.
*/
int ifconfig_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int ifconfig_main(int argc, char **argv)
{
struct ifreq ifr;
struct sockaddr_in sai;
#if ENABLE_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 selector;
#if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
unsigned int mask;
unsigned int did_flags;
unsigned int sai_hostname, sai_netmask;
#else
unsigned char mask;
unsigned char did_flags;
#endif
char *p;
/*char host[128];*/
const char *host = NULL; /* make gcc happy */
did_flags = 0;
#if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
sai_hostname = 0;
sai_netmask = 0;
#endif
/* skip argv[0] */
++argv;
--argc;
#if ENABLE_FEATURE_IFCONFIG_STATUS
if (argc > 0 && (argv[0][0] == '-' && argv[0][1] == 'a' && !argv[0][2])) {
interface_opt_a = 1;
--argc;
++argv;
}
#endif
if (argc <= 1) {
#if ENABLE_FEATURE_IFCONFIG_STATUS
return display_interfaces(argc ? *argv : NULL);
#else
bb_error_msg_and_die("no support for status display");
#endif
}
/* Create a channel to the NET kernel. */
sockfd = xsocket(AF_INET, SOCK_DGRAM, 0);
/* 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... */
mask &= op->flags;
if (mask) /* set the mask and go. */
goto FOUND_ARG;
/* If we get here, there was a valid arg with an */
/* invalid '-' prefix. */
bb_error_msg_and_die("bad: '%s'", p-1);
}
}
/* We fell through, so treat as possible hostname. */
a1op = Arg1Opt + ARRAY_SIZE(Arg1Opt) - 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)
bb_show_usage();
if (*++argv == NULL) {
if (mask & A_ARG_REQ)
bb_show_usage();
--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) {
#if ENABLE_FEATURE_IFCONFIG_HW
if (mask & A_CAST_RESOLVE) {
#endif
#if ENABLE_FEATURE_IPV6
char *prefix;
int prefix_len = 0;
#endif
/*safe_strncpy(host, *argv, (sizeof host));*/
host = *argv;
#if ENABLE_FEATURE_IPV6
prefix = strchr(host, '/');
if (prefix) {
prefix_len = xatou_range(prefix + 1, 0, 128);
*prefix = '\0';
}
#endif
sai.sin_family = AF_INET;
sai.sin_port = 0;
if (!strcmp(host, bb_str_default)) {
/* Default is special, meaning 0.0.0.0. */
sai.sin_addr.s_addr = INADDR_ANY;
}
#if ENABLE_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
else {
len_and_sockaddr *lsa;
if (strcmp(host, "inet") == 0)
continue; /* compat stuff */
lsa = xhost2sockaddr(host, 0);
#if ENABLE_FEATURE_IPV6
if (lsa->sa.sa_family == AF_INET6) {
int sockfd6;
struct in6_ifreq ifr6;
memcpy((char *) &ifr6.ifr6_addr,
(char *) &(lsa->sin6.sin6_addr),
sizeof(struct in6_addr));
/* Create a channel to the NET kernel. */
sockfd6 = xsocket(AF_INET6, SOCK_DGRAM, 0);
xioctl(sockfd6, SIOGIFINDEX, &ifr);
ifr6.ifr6_ifindex = ifr.ifr_ifindex;
ifr6.ifr6_prefixlen = prefix_len;
ioctl_or_perror_and_die(sockfd6, a1op->selector, &ifr6, "%s", a1op->name);
if (ENABLE_FEATURE_CLEAN_UP)
free(lsa);
continue;
}
#endif
sai.sin_addr = lsa->sin.sin_addr;
if (ENABLE_FEATURE_CLEAN_UP)
free(lsa);
}
#if ENABLE_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;
#if ENABLE_FEATURE_IFCONFIG_HW
} else { /* A_CAST_HOST_COPY_IN_ETHER */
/* This is the "hw" arg case. */
if (strcmp("ether", *argv) || !*++argv)
bb_show_usage();
/*safe_strncpy(host, *argv, sizeof(host));*/
host = *argv;
if (in_ether(host, &sa))
bb_error_msg_and_die("invalid hw-addr %s", host);
p = (char *) &sa;
}
#endif
memcpy( (((char *)&ifr) + a1op->ifr_offset),
p, sizeof(struct sockaddr));
} else {
/* FIXME: error check?? */
unsigned long i = strtoul(*argv, NULL, 0);
p = ((char *)&ifr) + a1op->ifr_offset;
#if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
if (mask & A_MAP_TYPE) {
xioctl(sockfd, SIOCGIFMAP, &ifr);
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;
}
ioctl_or_perror_and_die(sockfd, a1op->selector, &ifr, "%s", a1op->name);
#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;
}
xioctl(sockfd, SIOCGIFFLAGS, &ifr);
selector = op->selector;
if (mask & SET_MASK)
ifr.ifr_flags |= selector;
else
ifr.ifr_flags &= ~selector;
xioctl(sockfd, SIOCSIFFLAGS, &ifr);
} /* while () */
if (ENABLE_FEATURE_CLEAN_UP)
close(sockfd);
return 0;
}
#if ENABLE_FEATURE_IFCONFIG_HW
/* Input an Ethernet address and convert to binary. */
static int in_ether(const char *bufp, struct sockaddr *sap)
{
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 *bufp; /* Error if we don't end at end of string. */
}
#endif