| /* vi: set sw=4 ts=4: */ |
| /* |
| * 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 <net/if.h> |
| #include <net/if_packet.h> |
| #include <netpacket/packet.h> |
| #include <net/ethernet.h> |
| |
| #include "ip_common.h" /* #include "libbb.h" is inside */ |
| #include "rt_names.h" |
| #include "utils.h" |
| |
| /* taken from linux/sockios.h */ |
| #define SIOCSIFNAME 0x8923 /* set interface name */ |
| |
| /* Exits on error */ |
| static int get_ctl_fd(void) |
| { |
| int fd; |
| |
| fd = socket(PF_INET, SOCK_DGRAM, 0); |
| if (fd >= 0) |
| return fd; |
| fd = socket(PF_PACKET, SOCK_DGRAM, 0); |
| if (fd >= 0) |
| return fd; |
| return xsocket(PF_INET6, SOCK_DGRAM, 0); |
| } |
| |
| /* Exits on error */ |
| static void do_chflags(char *dev, uint32_t flags, uint32_t mask) |
| { |
| struct ifreq ifr; |
| int fd; |
| |
| strncpy_IFNAMSIZ(ifr.ifr_name, dev); |
| fd = get_ctl_fd(); |
| xioctl(fd, SIOCGIFFLAGS, &ifr); |
| if ((ifr.ifr_flags ^ flags) & mask) { |
| ifr.ifr_flags &= ~mask; |
| ifr.ifr_flags |= mask & flags; |
| xioctl(fd, SIOCSIFFLAGS, &ifr); |
| } |
| close(fd); |
| } |
| |
| /* Exits on error */ |
| static void do_changename(char *dev, char *newdev) |
| { |
| struct ifreq ifr; |
| int fd; |
| |
| strncpy_IFNAMSIZ(ifr.ifr_name, dev); |
| strncpy_IFNAMSIZ(ifr.ifr_newname, newdev); |
| fd = get_ctl_fd(); |
| xioctl(fd, SIOCSIFNAME, &ifr); |
| close(fd); |
| } |
| |
| /* Exits on error */ |
| static void set_qlen(char *dev, int qlen) |
| { |
| struct ifreq ifr; |
| int s; |
| |
| s = get_ctl_fd(); |
| memset(&ifr, 0, sizeof(ifr)); |
| strncpy_IFNAMSIZ(ifr.ifr_name, dev); |
| ifr.ifr_qlen = qlen; |
| xioctl(s, SIOCSIFTXQLEN, &ifr); |
| close(s); |
| } |
| |
| /* Exits on error */ |
| static void set_mtu(char *dev, int mtu) |
| { |
| struct ifreq ifr; |
| int s; |
| |
| s = get_ctl_fd(); |
| memset(&ifr, 0, sizeof(ifr)); |
| strncpy_IFNAMSIZ(ifr.ifr_name, dev); |
| ifr.ifr_mtu = mtu; |
| xioctl(s, SIOCSIFMTU, &ifr); |
| close(s); |
| } |
| |
| /* Exits on error */ |
| static int get_address(char *dev, int *htype) |
| { |
| struct ifreq ifr; |
| struct sockaddr_ll me; |
| socklen_t alen; |
| int s; |
| |
| s = xsocket(PF_PACKET, SOCK_DGRAM, 0); |
| |
| memset(&ifr, 0, sizeof(ifr)); |
| strncpy_IFNAMSIZ(ifr.ifr_name, dev); |
| xioctl(s, SIOCGIFINDEX, &ifr); |
| |
| memset(&me, 0, sizeof(me)); |
| me.sll_family = AF_PACKET; |
| me.sll_ifindex = ifr.ifr_ifindex; |
| me.sll_protocol = htons(ETH_P_LOOP); |
| xbind(s, (struct sockaddr*)&me, sizeof(me)); |
| alen = sizeof(me); |
| getsockname(s, (struct sockaddr*)&me, &alen); |
| //never happens: |
| //if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) |
| // bb_perror_msg_and_die("getsockname"); |
| close(s); |
| *htype = me.sll_hatype; |
| return me.sll_halen; |
| } |
| |
| /* Exits on error */ |
| static void parse_address(char *dev, int hatype, int halen, char *lla, struct ifreq *ifr) |
| { |
| int alen; |
| |
| memset(ifr, 0, sizeof(*ifr)); |
| strncpy_IFNAMSIZ(ifr->ifr_name, dev); |
| ifr->ifr_hwaddr.sa_family = hatype; |
| |
| alen = hatype == 1/*ARPHRD_ETHER*/ ? 14/*ETH_HLEN*/ : 19/*INFINIBAND_HLEN*/; |
| alen = ll_addr_a2n((unsigned char *)(ifr->ifr_hwaddr.sa_data), alen, lla); |
| if (alen < 0) |
| exit(EXIT_FAILURE); |
| if (alen != halen) { |
| bb_error_msg_and_die("wrong address (%s) length: expected %d bytes", lla, halen); |
| } |
| } |
| |
| /* Exits on error */ |
| static void set_address(struct ifreq *ifr, int brd) |
| { |
| int s; |
| |
| s = get_ctl_fd(); |
| if (brd) |
| xioctl(s, SIOCSIFHWBROADCAST, ifr); |
| else |
| xioctl(s, SIOCSIFHWADDR, ifr); |
| close(s); |
| } |
| |
| |
| static void die_must_be_on_off(const char *msg) NORETURN; |
| static void die_must_be_on_off(const char *msg) |
| { |
| bb_error_msg_and_die("argument of \"%s\" must be \"on\" or \"off\"", msg); |
| } |
| |
| /* Return value becomes exitcode. It's okay to not return at all */ |
| static int do_set(char **argv) |
| { |
| char *dev = NULL; |
| uint32_t mask = 0; |
| uint32_t flags = 0; |
| int qlen = -1; |
| int mtu = -1; |
| char *newaddr = NULL; |
| char *newbrd = NULL; |
| struct ifreq ifr0, ifr1; |
| char *newname = NULL; |
| int htype, halen; |
| static const char keywords[] ALIGN1 = |
| "up\0""down\0""name\0""mtu\0""multicast\0" |
| "arp\0""address\0""dev\0"; |
| enum { ARG_up = 0, ARG_down, ARG_name, ARG_mtu, ARG_multicast, |
| ARG_arp, ARG_addr, ARG_dev }; |
| static const char str_on_off[] ALIGN1 = "on\0""off\0"; |
| enum { PARM_on = 0, PARM_off }; |
| smalluint key; |
| |
| while (*argv) { |
| /* substring search ensures that e.g. "addr" and "address" |
| * are both accepted */ |
| key = index_in_substrings(keywords, *argv); |
| if (key == ARG_up) { |
| mask |= IFF_UP; |
| flags |= IFF_UP; |
| } |
| if (key == ARG_down) { |
| mask |= IFF_UP; |
| flags &= ~IFF_UP; |
| } |
| if (key == ARG_name) { |
| NEXT_ARG(); |
| newname = *argv; |
| } |
| if (key == ARG_mtu) { |
| NEXT_ARG(); |
| if (mtu != -1) |
| duparg("mtu", *argv); |
| mtu = get_unsigned(*argv, "mtu"); |
| } |
| if (key == ARG_multicast) { |
| int param; |
| NEXT_ARG(); |
| mask |= IFF_MULTICAST; |
| param = index_in_strings(str_on_off, *argv); |
| if (param < 0) |
| die_must_be_on_off("multicast"); |
| if (param == PARM_on) |
| flags |= IFF_MULTICAST; |
| else |
| flags &= ~IFF_MULTICAST; |
| } |
| if (key == ARG_arp) { |
| int param; |
| NEXT_ARG(); |
| mask |= IFF_NOARP; |
| param = index_in_strings(str_on_off, *argv); |
| if (param < 0) |
| die_must_be_on_off("arp"); |
| if (param == PARM_on) |
| flags &= ~IFF_NOARP; |
| else |
| flags |= IFF_NOARP; |
| } |
| if (key == ARG_addr) { |
| NEXT_ARG(); |
| newaddr = *argv; |
| } |
| if (key >= ARG_dev) { |
| if (key == ARG_dev) { |
| NEXT_ARG(); |
| } |
| if (dev) |
| duparg2("dev", *argv); |
| dev = *argv; |
| } |
| argv++; |
| } |
| |
| if (!dev) { |
| bb_error_msg_and_die(bb_msg_requires_arg, "\"dev\""); |
| } |
| |
| if (newaddr || newbrd) { |
| halen = get_address(dev, &htype); |
| if (newaddr) { |
| parse_address(dev, htype, halen, newaddr, &ifr0); |
| } |
| if (newbrd) { |
| parse_address(dev, htype, halen, newbrd, &ifr1); |
| } |
| } |
| |
| if (newname && strcmp(dev, newname)) { |
| do_changename(dev, newname); |
| dev = newname; |
| } |
| if (qlen != -1) { |
| set_qlen(dev, qlen); |
| } |
| if (mtu != -1) { |
| set_mtu(dev, mtu); |
| } |
| if (newaddr || newbrd) { |
| if (newbrd) { |
| set_address(&ifr1, 1); |
| } |
| if (newaddr) { |
| set_address(&ifr0, 0); |
| } |
| } |
| if (mask) |
| do_chflags(dev, flags, mask); |
| return 0; |
| } |
| |
| static int ipaddr_list_link(char **argv) |
| { |
| preferred_family = AF_PACKET; |
| return ipaddr_list_or_flush(argv, 0); |
| } |
| |
| #ifndef NLMSG_TAIL |
| #define NLMSG_TAIL(nmsg) \ |
| ((struct rtattr *) (((void *) (nmsg)) + NLMSG_ALIGN((nmsg)->nlmsg_len))) |
| #endif |
| /* Return value becomes exitcode. It's okay to not return at all */ |
| static int do_change(char **argv, const unsigned rtm) |
| { |
| static const char keywords[] ALIGN1 = |
| "link\0""name\0""type\0""dev\0"; |
| enum { |
| ARG_link, |
| ARG_name, |
| ARG_type, |
| ARG_dev, |
| }; |
| struct rtnl_handle rth; |
| struct { |
| struct nlmsghdr n; |
| struct ifinfomsg i; |
| char buf[1024]; |
| } req; |
| int arg; |
| char *name_str = NULL, *link_str = NULL, *type_str = NULL, *dev_str = NULL; |
| |
| memset(&req, 0, sizeof(req)); |
| |
| req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)); |
| req.n.nlmsg_flags = NLM_F_REQUEST; |
| req.n.nlmsg_type = rtm; |
| req.i.ifi_family = preferred_family; |
| if (rtm == RTM_NEWLINK) |
| req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL; |
| |
| while (*argv) { |
| arg = index_in_substrings(keywords, *argv); |
| if (arg == ARG_link) { |
| NEXT_ARG(); |
| link_str = *argv; |
| } else if (arg == ARG_name) { |
| NEXT_ARG(); |
| name_str = *argv; |
| } else if (arg == ARG_type) { |
| NEXT_ARG(); |
| type_str = *argv; |
| } else { |
| if (arg == ARG_dev) { |
| if (dev_str) |
| duparg(*argv, "dev"); |
| NEXT_ARG(); |
| } |
| dev_str = *argv; |
| } |
| argv++; |
| } |
| xrtnl_open(&rth); |
| ll_init_map(&rth); |
| if (type_str) { |
| struct rtattr *linkinfo = NLMSG_TAIL(&req.n); |
| |
| addattr_l(&req.n, sizeof(req), IFLA_LINKINFO, NULL, 0); |
| addattr_l(&req.n, sizeof(req), IFLA_INFO_KIND, type_str, |
| strlen(type_str)); |
| linkinfo->rta_len = (void *)NLMSG_TAIL(&req.n) - (void *)linkinfo; |
| } |
| if (rtm != RTM_NEWLINK) { |
| if (!dev_str) |
| return 1; /* Need a device to delete */ |
| req.i.ifi_index = xll_name_to_index(dev_str); |
| } else { |
| if (!name_str) |
| name_str = dev_str; |
| if (link_str) { |
| int idx = xll_name_to_index(link_str); |
| addattr_l(&req.n, sizeof(req), IFLA_LINK, &idx, 4); |
| } |
| } |
| if (name_str) { |
| const size_t name_len = strlen(name_str) + 1; |
| if (name_len < 2 || name_len > IFNAMSIZ) |
| invarg(name_str, "name"); |
| addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name_str, name_len); |
| } |
| if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0) |
| return 2; |
| return 0; |
| } |
| |
| /* Return value becomes exitcode. It's okay to not return at all */ |
| int do_iplink(char **argv) |
| { |
| static const char keywords[] ALIGN1 = |
| "add\0""delete\0""set\0""show\0""lst\0""list\0"; |
| int key; |
| if (!*argv) |
| return ipaddr_list_link(argv); |
| key = index_in_substrings(keywords, *argv); |
| if (key < 0) |
| bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name); |
| argv++; |
| if (key <= 1) /* add/delete */ |
| return do_change(argv, key ? RTM_DELLINK : RTM_NEWLINK); |
| else if (key == 2) /* set */ |
| return do_set(argv); |
| /* show, lst, list */ |
| return ipaddr_list_link(argv); |
| } |