diff options
| author | Paul Davey <paul.davey@alliedtelesis.co.nz> | 2020-09-08 10:04:07 +1200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-09-10 12:25:51 -0700 |
| commit | c8715a8e9f38906e73d6d78764216742db13ba0e (patch) | |
| tree | e6dc103986d2225073173e28fefefedd8ee5d51c | |
| parent | 501cb008906631a019f3ab2104a17ef8b2651ed0 (diff) | |
ipmr: Add high byte of VIF ID to igmpmsg
Use the unused3 byte in struct igmpmsg to hold the high 8 bits of the
VIF ID.
If using more than 255 IPv4 multicast interfaces it is necessary to have
access to a VIF ID for cache reports that is wider than 8 bits, the VIF
ID present in the igmpmsg reports sent to mroute_sk was only 8 bits wide
in the igmpmsg header. Adding the high 8 bits of the 16 bit VIF ID in
the unused byte allows use of more than 255 IPv4 multicast interfaces.
Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/uapi/linux/mroute.h | 4 | ||||
| -rw-r--r-- | net/ipv4/ipmr.c | 8 |
2 files changed, 8 insertions, 4 deletions
diff --git a/include/uapi/linux/mroute.h b/include/uapi/linux/mroute.h index 918f1ef32ffe..1a42f5f9b31b 100644 --- a/include/uapi/linux/mroute.h +++ b/include/uapi/linux/mroute.h @@ -113,8 +113,8 @@ struct igmpmsg { __u32 unused1,unused2; unsigned char im_msgtype; /* What is this */ unsigned char im_mbz; /* Must be zero */ - unsigned char im_vif; /* Interface (this ought to be a vifi_t!) */ - unsigned char unused3; + unsigned char im_vif; /* Low 8 bits of Interface */ + unsigned char im_vif_hi; /* High 8 bits of Interface */ struct in_addr im_src,im_dst; }; diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 19b2f586319b..4809318f591b 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -1038,10 +1038,13 @@ static int ipmr_cache_report(struct mr_table *mrt, memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr)); msg->im_msgtype = assert; msg->im_mbz = 0; - if (assert == IGMPMSG_WRVIFWHOLE) + if (assert == IGMPMSG_WRVIFWHOLE) { msg->im_vif = vifi; - else + msg->im_vif_hi = vifi >> 8; + } else { msg->im_vif = mrt->mroute_reg_vif_num; + msg->im_vif_hi = mrt->mroute_reg_vif_num >> 8; + } ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2; ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) + sizeof(struct iphdr)); @@ -1054,6 +1057,7 @@ static int ipmr_cache_report(struct mr_table *mrt, ip_hdr(skb)->protocol = 0; msg = (struct igmpmsg *)skb_network_header(skb); msg->im_vif = vifi; + msg->im_vif_hi = vifi >> 8; skb_dst_set(skb, dst_clone(skb_dst(pkt))); /* Add our header */ igmp = skb_put(skb, sizeof(struct igmphdr)); |