blob: 9e30122c38137af953f068230414f5de276f3300 [file] [log] [blame]
/*
* iplink.c "ip link".
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <net/if.h>
#include <net/if_packet.h>
#include <netpacket/packet.h>
#include <net/ethernet.h>
#include "rt_names.h"
#include "utils.h"
#include "ip_common.h"
/* take from linux/sockios.h */
#define SIOCSIFNAME 0x8923 /* set interface name */
static int do_link;
static int on_off(char *msg)
{
bb_error_msg("Error: argument of \"%s\" must be \"on\" or \"off\"", msg);
return -1;
}
static int get_ctl_fd(void)
{
int s_errno;
int fd;
fd = socket(PF_INET, SOCK_DGRAM, 0);
if (fd >= 0)
return fd;
s_errno = errno;
fd = socket(PF_PACKET, SOCK_DGRAM, 0);
if (fd >= 0)
return fd;
fd = socket(PF_INET6, SOCK_DGRAM, 0);
if (fd >= 0)
return fd;
errno = s_errno;
perror("Cannot create control socket");
return -1;
}
static int do_chflags(char *dev, __u32 flags, __u32 mask)
{
struct ifreq ifr;
int fd;
int err;
strcpy(ifr.ifr_name, dev);
fd = get_ctl_fd();
if (fd < 0)
return -1;
err = ioctl(fd, SIOCGIFFLAGS, &ifr);
if (err) {
perror("SIOCGIFFLAGS");
close(fd);
return -1;
}
if ((ifr.ifr_flags^flags)&mask) {
ifr.ifr_flags &= ~mask;
ifr.ifr_flags |= mask&flags;
err = ioctl(fd, SIOCSIFFLAGS, &ifr);
if (err)
perror("SIOCSIFFLAGS");
}
close(fd);
return err;
}
static int do_changename(char *dev, char *newdev)
{
struct ifreq ifr;
int fd;
int err;
strcpy(ifr.ifr_name, dev);
strcpy(ifr.ifr_newname, newdev);
fd = get_ctl_fd();
if (fd < 0)
return -1;
err = ioctl(fd, SIOCSIFNAME, &ifr);
if (err) {
perror("SIOCSIFNAME");
close(fd);
return -1;
}
close(fd);
return err;
}
static int set_qlen(char *dev, int qlen)
{
struct ifreq ifr;
int s;
s = get_ctl_fd();
if (s < 0)
return -1;
memset(&ifr, 0, sizeof(ifr));
strcpy(ifr.ifr_name, dev);
ifr.ifr_qlen = qlen;
if (ioctl(s, SIOCSIFTXQLEN, &ifr) < 0) {
perror("SIOCSIFXQLEN");
close(s);
return -1;
}
close(s);
return 0;
}
static int set_mtu(char *dev, int mtu)
{
struct ifreq ifr;
int s;
s = get_ctl_fd();
if (s < 0)
return -1;
memset(&ifr, 0, sizeof(ifr));
strcpy(ifr.ifr_name, dev);
ifr.ifr_mtu = mtu;
if (ioctl(s, SIOCSIFMTU, &ifr) < 0) {
perror("SIOCSIFMTU");
close(s);
return -1;
}
close(s);
return 0;
}
static int get_address(char *dev, int *htype)
{
struct ifreq ifr;
struct sockaddr_ll me;
socklen_t alen;
int s;
s = socket(PF_PACKET, SOCK_DGRAM, 0);
if (s < 0) {
perror("socket(PF_PACKET)");
return -1;
}
memset(&ifr, 0, sizeof(ifr));
strcpy(ifr.ifr_name, dev);
if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
perror("SIOCGIFINDEX");
close(s);
return -1;
}
memset(&me, 0, sizeof(me));
me.sll_family = AF_PACKET;
me.sll_ifindex = ifr.ifr_ifindex;
me.sll_protocol = htons(ETH_P_LOOP);
if (bind(s, (struct sockaddr*)&me, sizeof(me)) == -1) {
perror("bind");
close(s);
return -1;
}
alen = sizeof(me);
if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
perror("getsockname");
close(s);
return -1;
}
close(s);
*htype = me.sll_hatype;
return me.sll_halen;
}
static int parse_address(char *dev, int hatype, int halen, char *lla, struct ifreq *ifr)
{
int alen;
memset(ifr, 0, sizeof(*ifr));
strcpy(ifr->ifr_name, dev);
ifr->ifr_hwaddr.sa_family = hatype;
alen = ll_addr_a2n((unsigned char *)(ifr->ifr_hwaddr.sa_data), 14, lla);
if (alen < 0)
return -1;
if (alen != halen) {
bb_error_msg("Wrong address (%s) length: expected %d bytes", lla, halen);
return -1;
}
return 0;
}
static int set_address(struct ifreq *ifr, int brd)
{
int s;
s = get_ctl_fd();
if (s < 0)
return -1;
if (ioctl(s, brd?SIOCSIFHWBROADCAST:SIOCSIFHWADDR, ifr) < 0) {
perror(brd?"SIOCSIFHWBROADCAST":"SIOCSIFHWADDR");
close(s);
return -1;
}
close(s);
return 0;
}
static int do_set(int argc, char **argv)
{
char *dev = NULL;
__u32 mask = 0;
__u32 flags = 0;
int qlen = -1;
int mtu = -1;
char *newaddr = NULL;
char *newbrd = NULL;
struct ifreq ifr0, ifr1;
char *newname = NULL;
int htype, halen;
while (argc > 0) {
if (strcmp(*argv, "up") == 0) {
mask |= IFF_UP;
flags |= IFF_UP;
} else if (strcmp(*argv, "down") == 0) {
mask |= IFF_UP;
flags &= ~IFF_UP;
} else if (strcmp(*argv, "name") == 0) {
NEXT_ARG();
newname = *argv;
} else if (strcmp(*argv, "mtu") == 0) {
NEXT_ARG();
if (mtu != -1)
duparg("mtu", *argv);
if (get_integer(&mtu, *argv, 0))
invarg(*argv, "mtu");
} else if (strcmp(*argv, "multicast") == 0) {
NEXT_ARG();
mask |= IFF_MULTICAST;
if (strcmp(*argv, "on") == 0) {
flags |= IFF_MULTICAST;
} else if (strcmp(*argv, "off") == 0) {
flags &= ~IFF_MULTICAST;
} else
return on_off("multicast");
} else if (strcmp(*argv, "arp") == 0) {
NEXT_ARG();
mask |= IFF_NOARP;
if (strcmp(*argv, "on") == 0) {
flags &= ~IFF_NOARP;
} else if (strcmp(*argv, "off") == 0) {
flags |= IFF_NOARP;
} else
return on_off("noarp");
} else if (strcmp(*argv, "addr") == 0) {
NEXT_ARG();
newaddr = *argv;
} else {
if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
}
if (dev)
duparg2("dev", *argv);
dev = *argv;
}
argc--; argv++;
}
if (!dev) {
bb_error_msg(bb_msg_requires_arg, "\"dev\"");
exit(-1);
}
if (newaddr || newbrd) {
halen = get_address(dev, &htype);
if (halen < 0)
return -1;
if (newaddr) {
if (parse_address(dev, htype, halen, newaddr, &ifr0) < 0)
return -1;
}
if (newbrd) {
if (parse_address(dev, htype, halen, newbrd, &ifr1) < 0)
return -1;
}
}
if (newname && strcmp(dev, newname)) {
if (do_changename(dev, newname) < 0)
return -1;
dev = newname;
}
if (qlen != -1) {
if (set_qlen(dev, qlen) < 0)
return -1;
}
if (mtu != -1) {
if (set_mtu(dev, mtu) < 0)
return -1;
}
if (newaddr || newbrd) {
if (newbrd) {
if (set_address(&ifr1, 1) < 0)
return -1;
}
if (newaddr) {
if (set_address(&ifr0, 0) < 0)
return -1;
}
}
if (mask)
return do_chflags(dev, flags, mask);
return 0;
}
static int ipaddr_list_link(int argc, char **argv)
{
preferred_family = AF_PACKET;
do_link = 1;
return ipaddr_list_or_flush(argc, argv, 0);
}
int do_iplink(int argc, char **argv)
{
if (argc > 0) {
if (matches(*argv, "set") == 0)
return do_set(argc-1, argv+1);
if (matches(*argv, "show") == 0 ||
matches(*argv, "lst") == 0 ||
matches(*argv, "list") == 0)
return ipaddr_list_link(argc-1, argv+1);
} else
return ipaddr_list_link(0, NULL);
bb_error_msg("Command \"%s\" is unknown.", *argv);
exit(-1);
}