| /* GTP specific RTNetlink helper functions */ |
| |
| /* (C) 2014 by sysmocom - s.f.m.c. GmbH |
| * Author: Pablo Neira Ayuso <pablo@gnumonks.org> |
| * |
| * All Rights Reserved |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU Lesser General Public License as |
| * published by the Free Software Foundation; either version 2 of the |
| * License, or (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| * |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <time.h> |
| |
| #include <libmnl/libmnl.h> |
| #include <net/if.h> |
| #include <linux/if_link.h> |
| #include <linux/rtnetlink.h> |
| #include <libgtpnl/gtpnl.h> |
| #include <linux/gtp.h> |
| #include <linux/if_link.h> |
| #include <netinet/in.h> |
| #include <arpa/inet.h> |
| #include <time.h> |
| |
| #include "internal.h" |
| |
| static struct nlmsghdr * |
| gtp_put_nlmsg(char *buf, uint16_t type, uint16_t nl_flags, uint32_t seq) |
| { |
| struct nlmsghdr *nlh; |
| |
| nlh = mnl_nlmsg_put_header(buf); |
| nlh->nlmsg_type = type; |
| nlh->nlmsg_flags = NLM_F_REQUEST | nl_flags; |
| nlh->nlmsg_seq = seq; |
| |
| return nlh; |
| } |
| |
| static struct mnl_socket *rtnl_open(void) |
| { |
| struct mnl_socket *nl; |
| |
| nl = mnl_socket_open(NETLINK_ROUTE); |
| if (nl == NULL) { |
| perror("mnl_socket_open"); |
| return NULL; |
| } |
| |
| if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) { |
| perror("mnl_socket_bind"); |
| goto err; |
| } |
| |
| return nl; |
| err: |
| mnl_socket_close(nl); |
| return NULL; |
| } |
| |
| static int rtnl_talk(struct mnl_socket *nl, struct nlmsghdr *nlh) |
| { |
| char buf[MNL_SOCKET_BUFFER_SIZE]; |
| int ret; |
| |
| ret = mnl_socket_sendto(nl, nlh, nlh->nlmsg_len); |
| if (ret < 0) |
| return ret; |
| |
| ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); |
| if (ret < 0) |
| return ret; |
| |
| return mnl_cb_run(buf, ret, nlh->nlmsg_seq, mnl_socket_get_portid(nl), |
| NULL, NULL); |
| } |
| |
| static int gtp_dev_talk(struct nlmsghdr *nlh, uint32_t seq) |
| { |
| struct mnl_socket *nl; |
| int ret; |
| |
| nl = rtnl_open(); |
| if (nl == NULL) |
| return -1; |
| |
| ret = rtnl_talk(nl, nlh); |
| |
| mnl_socket_close(nl); |
| return ret; |
| } |
| |
| static int _gtp_dev_create(int dest_ns, const char *gtp_ifname, int fd0, |
| int fd1, enum ifla_gtp_role role) |
| { |
| char buf[MNL_SOCKET_BUFFER_SIZE]; |
| struct nlmsghdr *nlh; |
| struct ifinfomsg *ifm; |
| unsigned int seq = time(NULL); |
| struct nlattr *nest, *nest2; |
| |
| nlh = gtp_put_nlmsg(buf, RTM_NEWLINK, |
| NLM_F_CREATE | NLM_F_EXCL | NLM_F_ACK, seq); |
| ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ifm)); |
| ifm->ifi_family = AF_INET; |
| ifm->ifi_change |= IFF_UP; |
| ifm->ifi_flags |= IFF_UP; |
| |
| if (dest_ns >= 0) |
| mnl_attr_put_u32(nlh, IFLA_NET_NS_FD, dest_ns); |
| mnl_attr_put_str(nlh, IFLA_IFNAME, gtp_ifname); |
| nest = mnl_attr_nest_start(nlh, IFLA_LINKINFO); |
| mnl_attr_put_str(nlh, IFLA_INFO_KIND, "gtp"); |
| nest2 = mnl_attr_nest_start(nlh, IFLA_INFO_DATA); |
| mnl_attr_put_u32(nlh, IFLA_GTP_FD0, fd0); |
| mnl_attr_put_u32(nlh, IFLA_GTP_FD1, fd1); |
| mnl_attr_put_u32(nlh, IFLA_GTP_PDP_HASHSIZE, 131072); |
| if (role != GTP_ROLE_GGSN) |
| mnl_attr_put_u32(nlh, IFLA_GTP_ROLE, role); |
| mnl_attr_nest_end(nlh, nest2); |
| mnl_attr_nest_end(nlh, nest); |
| |
| return gtp_dev_talk(nlh, seq); |
| } |
| |
| int gtp_dev_create(int dest_ns, const char *gtp_ifname, int fd0, int fd1) |
| { |
| return _gtp_dev_create(dest_ns, gtp_ifname, fd0, fd1, GTP_ROLE_GGSN); |
| } |
| EXPORT_SYMBOL(gtp_dev_create); |
| |
| int gtp_dev_create_sgsn(int dest_ns, const char *gtp_ifname, int fd0, int fd1) |
| { |
| return _gtp_dev_create(dest_ns, gtp_ifname, fd0, fd1, GTP_ROLE_SGSN); |
| } |
| EXPORT_SYMBOL(gtp_dev_create_sgsn); |
| |
| int gtp_dev_destroy(const char *gtp_ifname) |
| { |
| char buf[MNL_SOCKET_BUFFER_SIZE]; |
| struct nlmsghdr *nlh; |
| struct ifinfomsg *ifm; |
| unsigned int seq = time(NULL); |
| |
| nlh = gtp_put_nlmsg(buf, RTM_DELLINK, NLM_F_ACK, seq); |
| ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ifm)); |
| ifm->ifi_family = AF_INET; |
| ifm->ifi_change |= IFF_UP; |
| ifm->ifi_flags &= ~IFF_UP; |
| ifm->ifi_index = if_nametoindex(gtp_ifname); |
| |
| return gtp_dev_talk(nlh, seq); |
| } |
| EXPORT_SYMBOL(gtp_dev_destroy); |
| |
| int gtp_dev_config(const char *ifname, struct in_addr *dst, uint32_t prefix) |
| { |
| struct mnl_socket *nl; |
| char buf[MNL_SOCKET_BUFFER_SIZE]; |
| struct nlmsghdr *nlh; |
| struct rtmsg *rtm; |
| int iface, ret; |
| |
| iface = if_nametoindex(ifname); |
| if (iface == 0) { |
| perror("if_nametoindex"); |
| return -1; |
| } |
| |
| nlh = mnl_nlmsg_put_header(buf); |
| nlh->nlmsg_type = RTM_NEWROUTE; |
| nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_ACK; |
| nlh->nlmsg_seq = time(NULL); |
| |
| rtm = mnl_nlmsg_put_extra_header(nlh, sizeof(struct rtmsg)); |
| rtm->rtm_family = AF_INET; |
| rtm->rtm_dst_len = prefix; |
| rtm->rtm_src_len = 0; |
| rtm->rtm_tos = 0; |
| rtm->rtm_protocol = RTPROT_STATIC; |
| rtm->rtm_table = RT_TABLE_MAIN; |
| rtm->rtm_type = RTN_UNICAST; |
| rtm->rtm_scope = RT_SCOPE_UNIVERSE; |
| rtm->rtm_flags = 0; |
| |
| mnl_attr_put_u32(nlh, RTA_DST, dst->s_addr); |
| mnl_attr_put_u32(nlh, RTA_OIF, iface); |
| |
| nl = rtnl_open(); |
| if (nl == NULL) |
| return -1; |
| |
| ret = rtnl_talk(nl, nlh); |
| |
| mnl_socket_close(nl); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL(gtp_dev_config); |