ip: support SO_MARK cmsg
Enable setting skb->mark for UDP and RAW sockets using cmsg.
This is analogous to existing support for TOS, TTL, txtime, etc.
Packet sockets already support this as of commit c7d39e32632e
("packet: support per-packet fwmark for af_packet sendmsg").
Similar to other fields, implement by
1. initialize the sockcm_cookie.mark from socket option sk_mark
2. optionally overwrite this in ip_cmsg_send/ip6_datagram_send_ctl
3. initialize inet_cork.mark from sockcm_cookie.mark
4. initialize each (usually just one) skb->mark from inet_cork.mark
Step 1 is handled in one location for most protocols by ipcm_init_sk
as of commit 351782067b6b ("ipv4: ipcm_cookie initializers").
Signed-off-by: Willem de Bruijn <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
diff --git a/include/net/ip.h b/include/net/ip.h
index 29d89de..95bb77f 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -88,6 +88,7 @@ static inline void ipcm_init_sk(struct ipcm_cookie *ipcm,
{
ipcm_init(ipcm);
+ ipcm->sockc.mark = inet->sk.sk_mark;
ipcm->sockc.tsflags = inet->sk.sk_tsflags;
ipcm->oif = inet->sk.sk_bound_dev_if;
ipcm->addr = inet->inet_saddr;
