/* * iplink.c "ip link". * * 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. * * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> * */ #include <sys/ioctl.h> #include <sys/socket.h> #include <errno.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <net/if.h> #include <net/if_packet.h> #include <netpacket/packet.h> #if __GLIBC__ >=2 && __GLIBC_MINOR >= 1 #include <net/ethernet.h> #else #include <linux/if_ether.h> #endif #include "rt_names.h" #include "utils.h" #include "ip_common.h" #include "libbb.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; int 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(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("Invalid \"mtu\" value\n", *argv); } 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, "dev") == 0) { NEXT_ARG(); } if (dev) duparg2("dev", *argv); dev = *argv; } argc--; argv++; } if (!dev) { bb_error_msg("Not enough of information: \"dev\" argument is required."); 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, try \"ip link help\".", *argv); exit(-1); }