diff options
| -rw-r--r-- | src/openvpn/route.c | 148 |
1 files changed, 136 insertions, 12 deletions
diff --git a/src/openvpn/route.c b/src/openvpn/route.c index baa4a23..ed21d15 100644 --- a/src/openvpn/route.c +++ b/src/openvpn/route.c @@ -45,6 +45,10 @@ #include "memdbg.h" +#if defined(TARGET_LINUX) || defined(TARGET_ANDROID) +#include <linux/rtnetlink.h> /* RTM_GETROUTE etc. */ +#endif + #ifdef WIN32 #define METRIC_NOT_USED ((DWORD)-1) #endif @@ -1119,10 +1123,9 @@ print_default_gateway(const int msglevel, { struct buffer out = alloc_buf_gc (256, &gc); buf_printf (&out, "ROUTE6_GATEWAY"); + buf_printf (&out, " %s", print_in6_addr (rgi6->gateway.addr_ipv6, 0, &gc)); if (rgi6->flags & RGI_ON_LINK) buf_printf (&out, " ON_LINK"); - else - buf_printf (&out, " %s", print_in6_addr (rgi6->gateway.addr_ipv6, 0, &gc)); if (rgi6->flags & RGI_NETMASK_DEFINED) buf_printf (&out, "/%d", rgi6->gateway.netbits_ipv6); #ifdef WIN32 @@ -2677,22 +2680,143 @@ get_default_gateway (struct route_gateway_info *rgi) gc_free (&gc); } -/* IPv6 implementation using netlink (TBD) +/* IPv6 implementation using netlink + * http://www.linuxjournal.com/article/7356 + * netlink(3), netlink(7), rtnetlink(7) + * http://www.virtualbox.org/svn/vbox/trunk/src/VBox/NetworkServices/NAT/rtmon_linux.c */ +struct rtreq { + struct nlmsghdr nh; + struct rtmsg rtm; + char attrbuf[512]; +}; + void get_default_gateway_ipv6(struct route_ipv6_gateway_info *rgi6, struct in6_addr *dest) { - msg(D_ROUTE, "no support for get_default_gateway_ipv6() on this system (Linux and Android)"); + int nls = -1; + struct rtreq rtreq; + struct rtattr *rta; + + char rtbuf[2000]; + ssize_t ssize; + CLEAR(*rgi6); - struct in6_addr g = IN6ADDR_LOOPBACK_INIT; - - rgi6->flags = RGI_ADDR_DEFINED | RGI_IFACE_DEFINED | RGI_HWADDR_DEFINED | - RGI_NETMASK_DEFINED; - rgi6->gateway.addr_ipv6 = g; - rgi6->gateway.netbits_ipv6 = 64; - memcpy( rgi6->hwaddr, "\1\2\3\4\5\6", 6 ); - strcpy( rgi6->iface, "eth1" ); + + nls = socket( PF_NETLINK, SOCK_RAW, NETLINK_ROUTE ); + if ( nls < 0 ) + { msg(M_WARN|M_ERRNO, "GDG6: socket() failed" ); goto done; } + + /* bind() is not needed, no unsolicited msgs coming in */ + + /* request best matching route, see netlink(7) for explanations + */ + CLEAR(rtreq); + rtreq.nh.nlmsg_type = RTM_GETROUTE; + rtreq.nh.nlmsg_flags = NLM_F_REQUEST; /* best match only */ + rtreq.rtm.rtm_family = AF_INET6; + rtreq.rtm.rtm_src_len = 0; /* not source dependent */ + rtreq.rtm.rtm_dst_len = 128; /* exact dst */ + rtreq.rtm.rtm_table = RT_TABLE_MAIN; + rtreq.rtm.rtm_protocol = RTPROT_UNSPEC; + rtreq.nh.nlmsg_len = NLMSG_SPACE(sizeof(rtreq.rtm)); + + /* set RTA_DST for target IPv6 address we want */ + rta = (struct rtattr *)(((char *) &rtreq)+NLMSG_ALIGN(rtreq.nh.nlmsg_len)); + rta->rta_type = RTA_DST; + rta->rta_len = RTA_LENGTH(16); + rtreq.nh.nlmsg_len = NLMSG_ALIGN(rtreq.nh.nlmsg_len) + + RTA_LENGTH(16); + + if ( dest == NULL ) /* ::, unspecified */ + memset( RTA_DATA(rta), 0, 16 ); /* :: = all-zero */ + else + memcpy( RTA_DATA(rta), (void *)dest, 16 ); + + /* send and receive reply */ + if ( send( nls, &rtreq, rtreq.nh.nlmsg_len, 0 ) < 0 ) + { msg(M_WARN|M_ERRNO, "GDG6: send() failed" ); goto done; } + + ssize = recv(nls, rtbuf, sizeof(rtbuf), MSG_TRUNC); + + if (ssize < 0) + { msg(M_WARN|M_ERRNO, "GDG6: recv() failed" ); goto done; } + + if (ssize > sizeof(rtbuf)) + { + msg(M_WARN, "get_default_gateway_ipv6: returned message too big for buffer (%d>%d)", (int)ssize, (int)sizeof(rtbuf) ); + goto done; + } + + struct nlmsghdr *nh; + + for (nh = (struct nlmsghdr *)rtbuf; + NLMSG_OK(nh, ssize); + nh = NLMSG_NEXT(nh, ssize)) + { + struct rtmsg *rtm; + int attrlen; + + if (nh->nlmsg_type == NLMSG_DONE) { break; } + + if (nh->nlmsg_type == NLMSG_ERROR) { + struct nlmsgerr *ne = (struct nlmsgerr *)NLMSG_DATA(nh); + msg(M_WARN, "GDG6: NLSMG_ERROR: error %d\n", ne->error); + break; + } + + if (nh->nlmsg_type != RTM_NEWROUTE) { + /* shouldn't happen */ + msg(M_WARN, "GDG6: unexpected msg_type %d", nh->nlmsg_type ); + continue; + } + + rtm = (struct rtmsg *)NLMSG_DATA(nh); + attrlen = RTM_PAYLOAD(nh); + + /* we're only looking for routes in the main table, as "we have + * no IPv6" will lead to a lookup result in "Local" (::/0 reject) + */ + if (rtm->rtm_family != AF_INET6 || + rtm->rtm_table != RT_TABLE_MAIN) + { continue; } /* we're not interested */ + + for (rta = RTM_RTA(rtm); + RTA_OK(rta, attrlen); + rta = RTA_NEXT(rta, attrlen)) + { + if (rta->rta_type == RTA_GATEWAY) { + if ( RTA_PAYLOAD(rta) != sizeof(struct in6_addr) ) + { msg(M_WARN, "GDG6: RTA_GW size mismatch"); continue; } + rgi6->gateway.addr_ipv6 = *(struct in6_addr*) RTA_DATA(rta); + rgi6->flags |= RGI_ADDR_DEFINED; + } + else if (rta->rta_type == RTA_OIF) { + char ifname[IF_NAMESIZE+1]; + int oif; + if ( RTA_PAYLOAD(rta) != sizeof(oif) ) + { msg(M_WARN, "GDG6: oif size mismatch"); continue; } + + memcpy(&oif, RTA_DATA(rta), sizeof(oif)); + if_indextoname(oif,ifname); + strncpy( rgi6->iface, ifname, sizeof(rgi6->iface)-1 ); + rgi6->flags |= RGI_IFACE_DEFINED; + } + } + } + + /* if we have an interface but no gateway, the destination is on-link */ + if ( ( rgi6->flags & (RGI_IFACE_DEFINED|RGI_ADDR_DEFINED) ) == + RGI_IFACE_DEFINED ) + { + rgi6->flags |= (RGI_ADDR_DEFINED | RGI_ON_LINK); + rgi6->gateway.addr_ipv6 = *dest; + } + + done: + if (nls >= 0) + close (nls); } #elif defined(TARGET_DARWIN) || defined(TARGET_SOLARIS) || \ |