diff options
| -rw-r--r-- | ip.h | 9 | ||||
| -rw-r--r-- | netlink.c | 15 |
2 files changed, 23 insertions, 1 deletions
@@ -24,6 +24,11 @@ #define IN4ADDR_ANY_INIT \ { .s_addr = htonl_constant(INADDR_ANY) } +#define IN4_IS_ADDR_LINKLOCAL(a) \ + ((ntohl(((struct in_addr *)(a))->s_addr) >> 16) == 0xa9fe) +#define IN4_IS_PREFIX_LINKLOCAL(a, len) \ + ((len) >= 16 && IN4_IS_ADDR_LINKLOCAL(a)) + #define L2_BUF_IP4_INIT(proto) \ { \ .version = 4, \ @@ -40,6 +45,10 @@ #define L2_BUF_IP4_PSUM(proto) ((uint32_t)htons_constant(0x4500) + \ (uint32_t)htons(0xff00 | (proto))) + +#define IN6_IS_PREFIX_LINKLOCAL(a, len) \ + ((len) >= 10 && IN6_IS_ADDR_LINKLOCAL(a)) + #define L2_BUF_IP6_INIT(proto) \ { \ .priority = 0, \ @@ -33,6 +33,7 @@ #include "util.h" #include "passt.h" #include "log.h" +#include "ip.h" #include "netlink.h" /* Netlink expects a buffer of at least 8kiB or the system page size, @@ -270,6 +271,7 @@ unsigned int nl_get_ext_if(int s, sa_family_t af) seq = nl_send(s, &req, RTM_GETROUTE, NLM_F_DUMP, sizeof(req)); nl_foreach_oftype(nh, status, s, buf, seq, RTM_NEWROUTE) { struct rtmsg *rtm = (struct rtmsg *)NLMSG_DATA(nh); + const void *dst = NULL; unsigned thisifi = 0; if (rtm->rtm_family != af) @@ -284,12 +286,23 @@ unsigned int nl_get_ext_if(int s, sa_family_t af) rtnh = (struct rtnexthop *)RTA_DATA(rta); thisifi = rtnh->rtnh_ifindex; + } else if (rta->rta_type == RTA_DST) { + dst = RTA_DATA(rta); } } if (!thisifi) continue; /* No interface for this route */ + /* Skip routes to link-local addresses */ + if (af == AF_INET && dst && + IN4_IS_PREFIX_LINKLOCAL(dst, rtm->rtm_dst_len)) + continue; + + if (af == AF_INET6 && dst && + IN6_IS_PREFIX_LINKLOCAL(dst, rtm->rtm_dst_len)) + continue; + if (rtm->rtm_dst_len == 0) { /* Default route */ ndef++; @@ -322,7 +335,7 @@ unsigned int nl_get_ext_if(int s, sa_family_t af) } if (!nany) - info("No interfaces with %s routes", af_name(af)); + info("No interfaces with usable %s routes", af_name(af)); return 0; } |