net: sctp: implement rfc6458, 5.3.5. SCTP_RCVINFO cmsg support
This patch implements section 5.3.5. of RFC6458, that is, support
for 'SCTP Receive Information Structure' (SCTP_RCVINFO) which is
placed into ancillary data cmsghdr structure for each recvmsg()
call.
This option can be enabled/disabled via setsockopt(2) on SOL_SCTP
level by setting an int value with 1/0 for SCTP_RECVRCVINFO in user
space applications as per RFC6458, section 8.1.29.
The sctp_rcvinfo structure is defined as per RFC as below ...
struct sctp_rcvinfo {
uint16_t rcv_sid;
uint16_t rcv_ssn;
uint16_t rcv_flags;
<-- 2 bytes hole -->
uint32_t rcv_ppid;
uint32_t rcv_tsn;
uint32_t rcv_cumtsn;
uint32_t rcv_context;
sctp_assoc_t rcv_assoc_id;
};
... and provided under cmsg_level IPPROTO_SCTP, cmsg_type
SCTP_RCVINFO, while cmsg_data[] contains struct sctp_rcvinfo.
An sctp_rcvinfo item always corresponds to the data in msg_iov.
Joint work with Daniel Borkmann.
Signed-off-by: Geir Ola Vaagland <geirola@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 7af9a0f..11d5df0 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -207,7 +207,9 @@
struct sctp_paddrparams paddrparam;
struct sctp_event_subscribe subscribe;
struct sctp_assocparams assocparams;
+
int user_frag;
+
__u32 autoclose;
__u8 nodelay;
__u8 disable_fragments;
@@ -215,6 +217,7 @@
__u8 frag_interleave;
__u32 adaptation_ind;
__u32 pd_point;
+ __u8 recvrcvinfo;
atomic_t pd_mode;
/* Receive to here while partial delivery is in effect. */