From 93ca3bb5df9bc8b2c60485e1cc6507c3d7c8e1fa Mon Sep 17 00:00:00 2001 From: =?utf8?q?Timo=20Ter=C3=A4s?= Date: Mon, 28 Mar 2011 22:40:53 +0000 Subject: [PATCH] net: gre: provide multicast mappings for ipv4 and ipv6 MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit My commit 6d55cb91a0020ac0 (gre: fix hard header destination address checking) broke multicast. The reason is that ip_gre used to get ipgre_header() calls with zero destination if we have NOARP or multicast destination. Instead the actual target was decided at ipgre_tunnel_xmit() time based on per-protocol dissection. Instead of allowing the "abuse" of ->header() calls with invalid destination, this creates multicast mappings for ip_gre. This also fixes "ip neigh show nud noarp" to display the proper multicast mappings used by the gre device. Reported-by: Doug Kehn Signed-off-by: Timo Teräs Acked-by: Doug Kehn Signed-off-by: David S. Miller --- include/net/if_inet6.h | 16 ++++++++++++++++ include/net/ip.h | 8 ++++++++ net/ipv4/arp.c | 3 +++ net/ipv6/ndisc.c | 2 ++ 4 files changed, 29 insertions(+) diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h index 04977eefb0ee..fccc2180c61b 100644 --- a/include/net/if_inet6.h +++ b/include/net/if_inet6.h @@ -286,5 +286,21 @@ static inline void ipv6_ib_mc_map(const struct in6_addr *addr, buf[9] = broadcast[9]; memcpy(buf + 10, addr->s6_addr + 6, 10); } + +static inline int ipv6_ipgre_mc_map(const struct in6_addr *addr, + const unsigned char *broadcast, char *buf) +{ + if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0) { + memcpy(buf, broadcast, 4); + } else { + /* v4mapped? */ + if ((addr->s6_addr32[0] | addr->s6_addr32[1] | + (addr->s6_addr32[2] ^ htonl(0x0000ffff))) != 0) + return -EINVAL; + memcpy(buf, &addr->s6_addr32[3], 4); + } + return 0; +} + #endif #endif diff --git a/include/net/ip.h b/include/net/ip.h index a4f631108c54..7c416583b710 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -339,6 +339,14 @@ static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, ch buf[16] = addr & 0x0f; } +static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) +{ + if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0) + memcpy(buf, broadcast, 4); + else + memcpy(buf, &naddr, sizeof(naddr)); +} + #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) #include #endif diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index 090d273d7865..1b74d3b64371 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -215,6 +215,9 @@ int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir) case ARPHRD_INFINIBAND: ip_ib_mc_map(addr, dev->broadcast, haddr); return 0; + case ARPHRD_IPGRE: + ip_ipgre_mc_map(addr, dev->broadcast, haddr); + return 0; default: if (dir) { memcpy(haddr, dev->broadcast, dev->addr_len); diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 0e49c9db3c98..92f952d093db 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -341,6 +341,8 @@ int ndisc_mc_map(struct in6_addr *addr, char *buf, struct net_device *dev, int d case ARPHRD_INFINIBAND: ipv6_ib_mc_map(addr, dev->broadcast, buf); return 0; + case ARPHRD_IPGRE: + return ipv6_ipgre_mc_map(addr, dev->broadcast, buf); default: if (dir) { memcpy(buf, dev->broadcast, dev->addr_len); -- 2.34.1