/* * Copyright 2012 Daniel Drown * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * * setif.c - network interface configuration */ #include #include #include #include #include #include #include "logging.h" #include "netlink_msg.h" #define DEBUG_OPTNAME(a) \ case (a): { \ optname = #a; \ break; \ } /* function: add_address * adds an IP address to/from an interface, returns 0 on success and <0 on failure * ifname - name of interface to change * family - address family (AF_INET, AF_INET6) * address - pointer to a struct in_addr or in6_addr * prefixlen - bitlength of network (example: 24 for AF_INET's 255.255.255.0) * broadcast - broadcast address (only for AF_INET, ignored for AF_INET6) */ int add_address(const char *ifname, int family, const void *address, int prefixlen, const void *broadcast) { int retval; size_t addr_size; struct ifaddrmsg ifa; struct nl_msg *msg = NULL; addr_size = inet_family_size(family); if (addr_size == 0) { retval = -EAFNOSUPPORT; goto cleanup; } memset(&ifa, 0, sizeof(ifa)); if (!(ifa.ifa_index = if_nametoindex(ifname))) { retval = -ENODEV; goto cleanup; } ifa.ifa_family = family; ifa.ifa_prefixlen = prefixlen; ifa.ifa_scope = RT_SCOPE_UNIVERSE; msg = nlmsg_alloc_ifaddr(RTM_NEWADDR, NLM_F_ACK | NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE, &ifa); if (!msg) { retval = -ENOMEM; goto cleanup; } if (nla_put(msg, IFA_LOCAL, addr_size, address) < 0) { retval = -ENOMEM; goto cleanup; } if (family == AF_INET6) { // AF_INET6 gets IFA_LOCAL + IFA_ADDRESS if (nla_put(msg, IFA_ADDRESS, addr_size, address) < 0) { retval = -ENOMEM; goto cleanup; } } else if (family == AF_INET) { // AF_INET gets IFA_LOCAL + IFA_BROADCAST if (nla_put(msg, IFA_BROADCAST, addr_size, broadcast) < 0) { retval = -ENOMEM; goto cleanup; } } else { retval = -EAFNOSUPPORT; goto cleanup; } retval = netlink_sendrecv(msg); cleanup: if (msg) nlmsg_free(msg); return retval; } /* function: if_up * sets interface link state to up and sets mtu, returns 0 on success and <0 on failure * ifname - interface name to change * mtu - new mtu */ int if_up(const char *ifname, int mtu) { int retval = -1; struct ifinfomsg ifi; struct nl_msg *msg = NULL; memset(&ifi, 0, sizeof(ifi)); if (!(ifi.ifi_index = if_nametoindex(ifname))) { retval = -ENODEV; goto cleanup; } ifi.ifi_change = IFF_UP; ifi.ifi_flags = IFF_UP; msg = nlmsg_alloc_ifinfo(RTM_SETLINK, NLM_F_ACK | NLM_F_REQUEST | NLM_F_ROOT, &ifi); if (!msg) { retval = -ENOMEM; goto cleanup; } if (nla_put(msg, IFLA_MTU, 4, &mtu) < 0) { retval = -ENOMEM; goto cleanup; } retval = netlink_sendrecv(msg); cleanup: if (msg) nlmsg_free(msg); return retval; } static int do_anycast_setsockopt(int sock, int what, struct in6_addr *addr, int ifindex) { struct ipv6_mreq mreq = { *addr, ifindex }; char *optname; int ret; switch (what) { DEBUG_OPTNAME(IPV6_JOIN_ANYCAST) DEBUG_OPTNAME(IPV6_LEAVE_ANYCAST) default: optname = "???"; break; } ret = setsockopt(sock, SOL_IPV6, what, &mreq, sizeof(mreq)); if (ret) { logmsg(ANDROID_LOG_ERROR, "%s: setsockopt(%s): %s", __func__, optname, strerror(errno)); } return ret; } /* function: add_anycast_address * adds an anycast IPv6 address to an interface, returns 0 on success and <0 on failure * sock - the socket to add the address to * addr - the IP address to add * ifname - name of interface to add the address to */ int add_anycast_address(int sock, struct in6_addr *addr, const char *ifname) { int ifindex; ifindex = if_nametoindex(ifname); if (!ifindex) { logmsg(ANDROID_LOG_ERROR, "%s: unknown ifindex for interface %s", __func__, ifname); return -ENODEV; } return do_anycast_setsockopt(sock, IPV6_JOIN_ANYCAST, addr, ifindex); } /* function: del_anycast_address * removes an anycast IPv6 address from the system, returns 0 on success and <0 on failure * sock - the socket to remove from, must have had the address added via add_anycast_address * addr - the IP address to remove */ int del_anycast_address(int sock, struct in6_addr *addr) { return do_anycast_setsockopt(sock, IPV6_LEAVE_ANYCAST, addr, 0); }