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-rw-r--r--src/6to4.c497
1 files changed, 497 insertions, 0 deletions
diff --git a/src/6to4.c b/src/6to4.c
new file mode 100644
index 00000000..767c8662
--- /dev/null
+++ b/src/6to4.c
@@ -0,0 +1,497 @@
+/*
+ *
+ * Connection Manager
+ *
+ * Copyright (C) 2011 Nokia Corporation. All rights reserved.
+ * Copyright (C) Alexey Kuznetsov et al. from iproute2 package.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <linux/ip.h>
+#include <linux/if_tunnel.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+#include "connman.h"
+#include <connman/log.h>
+#include <connman/ipconfig.h>
+
+static int tunnel_created;
+static int tunnel_pending;
+static char *tunnel_ip_address;
+
+#define NLMSG_TAIL(nmsg) \
+ ((struct rtattr *) (((void *)(nmsg)) + NLMSG_ALIGN((nmsg)->nlmsg_len)))
+
+#ifndef IP_DF
+#define IP_DF 0x4000 /* Flag: "Don't Fragment" */
+#endif
+
+struct rtnl_handle {
+ int fd;
+ struct sockaddr_nl local;
+ struct sockaddr_nl peer;
+ __u32 seq;
+ __u32 dump;
+};
+
+static int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data)
+{
+ int len = RTA_LENGTH(4);
+ struct rtattr *rta;
+ if (NLMSG_ALIGN(n->nlmsg_len) + len > (unsigned int)maxlen) {
+ DBG("Error! max allowed bound %d exceeded", maxlen);
+ return -1;
+ }
+ rta = NLMSG_TAIL(n);
+ rta->rta_type = type;
+ rta->rta_len = len;
+ memcpy(RTA_DATA(rta), &data, 4);
+ n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len;
+
+ return 0;
+}
+
+static int addattr_l(struct nlmsghdr *n, int maxlen, int type,
+ const void *data, int alen)
+{
+ int len = RTA_LENGTH(alen);
+ struct rtattr *rta;
+
+ if (NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len) >
+ (unsigned int)maxlen) {
+ DBG("addattr_l message exceeded bound of %d", maxlen);
+ return -1;
+ }
+ rta = NLMSG_TAIL(n);
+ rta->rta_type = type;
+ rta->rta_len = len;
+ memcpy(RTA_DATA(rta), data, alen);
+ n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
+
+ return 0;
+}
+
+static void rtnl_close(struct rtnl_handle *rth)
+{
+ if (rth->fd >= 0) {
+ close(rth->fd);
+ rth->fd = -1;
+ }
+}
+
+static int rtnl_open(struct rtnl_handle *rth)
+{
+ socklen_t addr_len;
+ int sndbuf = 1024;
+
+ memset(rth, 0, sizeof(*rth));
+
+ rth->fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+ if (rth->fd < 0) {
+ connman_error("Can not open netlink socket: %s",
+ strerror(errno));
+ return -1;
+ }
+
+ if (setsockopt(rth->fd, SOL_SOCKET, SO_SNDBUF, &sndbuf,
+ sizeof(sndbuf)) < 0) {
+ connman_error("SO_SNDBUF: %s", strerror(errno));
+ return -1;
+ }
+
+ memset(&rth->local, 0, sizeof(rth->local));
+ rth->local.nl_family = AF_NETLINK;
+ rth->local.nl_groups = 0;
+
+ if (bind(rth->fd, (struct sockaddr *)&rth->local,
+ sizeof(rth->local)) < 0) {
+ connman_error("Can not bind netlink socket: %s",
+ strerror(errno));
+ return -1;
+ }
+ addr_len = sizeof(rth->local);
+ if (getsockname(rth->fd, (struct sockaddr *)&rth->local,
+ &addr_len) < 0) {
+ connman_error("Can not getsockname: %s", strerror(errno));
+ return -1;
+ }
+ if (addr_len != sizeof(rth->local)) {
+ connman_error("Wrong address length %d", addr_len);
+ return -1;
+ }
+ if (rth->local.nl_family != AF_NETLINK) {
+ connman_error("Wrong address family %d", rth->local.nl_family);
+ return -1;
+ }
+ rth->seq = time(NULL);
+
+ return 0;
+}
+
+static int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n)
+{
+ struct sockaddr_nl nladdr;
+ struct iovec iov = {
+ .iov_base = (void *)n,
+ .iov_len = n->nlmsg_len
+ };
+ struct msghdr msg = {
+ .msg_name = &nladdr,
+ .msg_namelen = sizeof(nladdr),
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ };
+ unsigned seq;
+ int err;
+
+ memset(&nladdr, 0, sizeof(nladdr));
+ nladdr.nl_family = AF_NETLINK;
+
+ n->nlmsg_seq = seq = ++rtnl->seq;
+ n->nlmsg_flags |= NLM_F_ACK;
+
+ err = sendmsg(rtnl->fd, &msg, 0);
+ if (err < 0) {
+ connman_error("Can not talk to rtnetlink");
+ return err;
+ }
+
+ return 0;
+}
+
+static int tunnel_create(struct in_addr *addr)
+{
+ struct ip_tunnel_parm p;
+ struct ifreq ifr;
+ int fd = -1;
+ int ret;
+
+ /* ip tunnel add tun6to4 mode sit remote any local 1.2.3.4 ttl 64 */
+
+ memset(&p, 0, sizeof(struct ip_tunnel_parm));
+ memset(&ifr, 0, sizeof(struct ifreq));
+
+ p.iph.version = 4;
+ p.iph.ihl = 5;
+ p.iph.frag_off = htons(IP_DF);
+ p.iph.protocol = IPPROTO_IPV6;
+ p.iph.saddr = addr->s_addr;
+ p.iph.ttl = 64;
+ strncpy(p.name, "tun6to4", IFNAMSIZ);
+
+ strncpy(ifr.ifr_name, "sit0", IFNAMSIZ);
+ ifr.ifr_ifru.ifru_data = (void *)&p;
+ fd = socket(AF_INET, SOCK_DGRAM, 0);
+ ret = ioctl(fd, SIOCADDTUNNEL, &ifr);
+ if (ret)
+ connman_error("add tunnel %s failed: %s", ifr.ifr_name,
+ strerror(errno));
+ close(fd);
+
+ return ret;
+}
+
+static void tunnel_destroy()
+{
+ struct ip_tunnel_parm p;
+ struct ifreq ifr;
+ int fd = -1;
+ int ret;
+
+ if (tunnel_created == 0)
+ return;
+
+ /* ip tunnel del tun6to4 */
+
+ memset(&p, 0, sizeof(struct ip_tunnel_parm));
+ memset(&ifr, 0, sizeof(struct ifreq));
+
+ p.iph.version = 4;
+ p.iph.ihl = 5;
+ p.iph.protocol = IPPROTO_IPV6;
+ strncpy(p.name, "tun6to4", IFNAMSIZ);
+
+ strncpy(ifr.ifr_name, "tun6to4", IFNAMSIZ);
+ ifr.ifr_ifru.ifru_data = (void *)&p;
+ fd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (fd < 0) {
+ connman_error("socket failed: %s", strerror(errno));
+ return;
+ }
+
+ ret = ioctl(fd, SIOCDELTUNNEL, &ifr);
+ if (ret)
+ connman_error("del tunnel %s failed: %s", ifr.ifr_name,
+ strerror(errno));
+ else
+ tunnel_created = 0;
+
+ tunnel_pending = 0;
+ close(fd);
+
+ g_free(tunnel_ip_address);
+ tunnel_ip_address = NULL;
+}
+
+static int tunnel_add_route()
+{
+ struct rtnl_handle rth;
+ struct in6_addr addr6;
+ int index;
+ int ret = 0;
+
+ struct {
+ struct nlmsghdr n;
+ struct rtmsg r;
+ char buf[1024];
+ } req;
+
+ /* ip -6 route add ::/0 via ::192.88.99.1 dev tun6to4 metric 1 */
+
+ index = if_nametoindex("tun6to4");
+ if (index == 0) {
+ DBG("Can not find device tun6to4");
+ return -1;
+ }
+
+ memset(&req, 0, sizeof(req));
+
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
+ req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL;
+ req.n.nlmsg_type = RTM_NEWROUTE;
+ req.r.rtm_family = AF_INET6;
+ req.r.rtm_table = RT_TABLE_MAIN;
+ req.r.rtm_protocol = RTPROT_BOOT;
+ req.r.rtm_scope = RT_SCOPE_UNIVERSE;
+ req.r.rtm_type = RTN_UNICAST;
+ req.r.rtm_dst_len = 0;
+
+ inet_pton(AF_INET6, "::192.88.99.1", &addr6);
+
+ addattr_l(&req.n, sizeof(req), RTA_GATEWAY, &addr6.s6_addr, 16);
+ addattr32(&req.n, sizeof(req), RTA_OIF, index);
+ addattr32(&req.n, sizeof(req), RTA_PRIORITY, 1);
+
+ ret = rtnl_open(&rth);
+ if (ret < 0)
+ goto done;
+
+ ret = rtnl_talk(&rth, &req.n);
+
+done:
+ rtnl_close(&rth);
+ return ret;
+}
+
+static int tunnel_set_addr(unsigned int a, unsigned int b,
+ unsigned int c, unsigned int d)
+{
+ struct rtnl_handle rth;
+ struct in6_addr addr6;
+ char *ip6addr;
+ int ret;
+
+ struct {
+ struct nlmsghdr n;
+ struct ifaddrmsg ifa;
+ char buf[256];
+ } req;
+
+ /* ip -6 addr add dev tun6to4 2002:0102:0304::1/64 */
+
+ memset(&req, 0, sizeof(req));
+
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
+ req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL;
+ req.n.nlmsg_type = RTM_NEWADDR;
+ req.ifa.ifa_family = AF_INET6;
+ req.ifa.ifa_prefixlen = 64;
+ req.ifa.ifa_index = if_nametoindex("tun6to4");
+ if (req.ifa.ifa_index == 0) {
+ connman_error("Can not find device tun6to4");
+ ret = -1;
+ goto done;
+ }
+
+ ip6addr = g_strdup_printf("2002:%02x%02x:%02x%02x::1", a, b, c, d);
+ inet_pton(AF_INET6, ip6addr, &addr6);
+ DBG("ipv6 address %s", ip6addr);
+ g_free(ip6addr);
+
+ addattr_l(&req.n, sizeof(req), IFA_LOCAL, &addr6.s6_addr, 16);
+ addattr_l(&req.n, sizeof(req), IFA_ADDRESS, &addr6.s6_addr, 16);
+
+ ret = rtnl_open(&rth);
+ if (ret < 0)
+ goto done;
+
+ ret = rtnl_talk(&rth, &req.n);
+
+done:
+ rtnl_close(&rth);
+ return ret;
+}
+
+static int init_6to4(struct in_addr *ip4addr)
+{
+ unsigned int a, b, c, d;
+ in_addr_t addr;
+ int ret;
+
+ DBG("");
+
+ addr = ntohl(ip4addr->s_addr);
+
+ a = (addr & 0xff000000) >> 24;
+ b = (addr & 0x00ff0000) >> 16;
+ c = (addr & 0x0000ff00) >> 8;
+ d = addr & 0x000000ff;
+
+ ret = tunnel_create(ip4addr);
+ if (ret)
+ return -1;
+
+ tunnel_created = 1;
+
+ ret = connman_inet_setup_tunnel("tun6to4", 1472);
+ if (ret)
+ goto error;
+
+ ret = tunnel_set_addr(a, b, c, d);
+ if (ret)
+ goto error;
+
+ ret = tunnel_add_route();
+ if (ret)
+ goto error;
+
+ tunnel_pending = 0;
+ return 0;
+
+error:
+ tunnel_destroy();
+ return -1;
+}
+
+static void receive_rs_reply(struct nd_router_advert *reply, void *user_data)
+{
+ char *address = user_data;
+ struct in_addr ip4addr;
+
+ DBG("reply %p address %s", reply, address);
+
+ /* We try to create tunnel if autoconfiguration did not work i.e.,
+ * we did not receive any reply to router solicitation message.
+ */
+ if (reply == NULL && inet_aton(address, &ip4addr) != 0)
+ init_6to4(&ip4addr);
+
+ g_free(address);
+}
+
+int __connman_6to4_probe(struct connman_service *service)
+{
+ struct connman_ipconfig *ip4config, *ip6config;
+ enum connman_ipconfig_method method;
+ unsigned int a, b, c, d;
+ struct in_addr ip4addr;
+ in_addr_t addr;
+ const char *address;
+ char *ip_address;
+ int index;
+
+ DBG("service %p", service);
+
+ if (tunnel_created || tunnel_pending)
+ return 0;
+
+ if (service == NULL)
+ return -1;
+
+ ip4config = __connman_service_get_ip4config(service);
+ if (ip4config == NULL)
+ return -1;
+
+ ip6config = __connman_service_get_ip6config(service);
+ if (ip6config == NULL)
+ return -1;
+
+ method = __connman_ipconfig_get_method(ip6config);
+ if (method != CONNMAN_IPCONFIG_METHOD_AUTO)
+ return -1;
+
+ address = __connman_ipconfig_get_local(ip4config);
+ if (address == NULL)
+ return -1;
+
+ if (inet_aton(address, &ip4addr) == 0)
+ return -1;
+
+ addr = ntohl(ip4addr.s_addr);
+
+ a = (addr & 0xff000000) >> 24;
+ b = (addr & 0x00ff0000) >> 16;
+ c = (addr & 0x0000ff00) >> 8;
+ d = addr & 0x000000ff;
+
+ /* 6to4 tunnel is only usable if we have a public IPv4 address */
+ if (a == 10 || (a == 192 && b == 168) ||
+ (a == 172 && (b >= 16 && b <= 31)))
+ return -1;
+
+ index = connman_ipconfig_get_index(ip4config);
+ ip_address = g_strdup(address);
+ tunnel_pending = 1;
+
+ g_free(tunnel_ip_address);
+ tunnel_ip_address = g_strdup(address);
+
+ return __connman_inet_ipv6_send_rs(index, 2, receive_rs_reply,
+ ip_address);
+}
+
+void __connman_6to4_remove(struct connman_ipconfig *ip4config)
+{
+ const char *address;
+
+ DBG("tunnel ip address %s", tunnel_ip_address);
+
+ if (ip4config == NULL)
+ return;
+
+ address = __connman_ipconfig_get_local(ip4config);
+ if (address == NULL)
+ return;
+
+ if (g_strcmp0(address, tunnel_ip_address) != 0)
+ return;
+
+ if (tunnel_created)
+ tunnel_destroy();
+}
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