mptcp: parse and emit MP_CAPABLE option according to v1 spec
This implements MP_CAPABLE options parsing and writing according
to RFC 6824 bis / RFC 8684: MPTCP v1.
Local key is sent on syn/ack, and both keys are sent on 3rd ack.
MP_CAPABLE messages len are updated accordingly. We need the skbuff to
correctly emit the above, so we push the skbuff struct as an argument
all the way from tcp code to the relevant mptcp callbacks.
When processing incoming MP_CAPABLE + data, build a full blown DSS-like
map info, to simplify later processing. On child socket creation, we
need to record the remote key, if available.
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index a355bb1..36b9002 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -11,7 +11,7 @@
#include <net/tcp.h>
#include <net/inet_connection_sock.h>
-#define MPTCP_SUPPORTED_VERSION 0
+#define MPTCP_SUPPORTED_VERSION 1
/* MPTCP option bits */
#define OPTION_MPTCP_MPC_SYN BIT(0)
@@ -29,9 +29,10 @@
#define MPTCPOPT_MP_FASTCLOSE 7
/* MPTCP suboption lengths */
-#define TCPOLEN_MPTCP_MPC_SYN 12
+#define TCPOLEN_MPTCP_MPC_SYN 4
#define TCPOLEN_MPTCP_MPC_SYNACK 12
#define TCPOLEN_MPTCP_MPC_ACK 20
+#define TCPOLEN_MPTCP_MPC_ACK_DATA 22
#define TCPOLEN_MPTCP_DSS_BASE 4
#define TCPOLEN_MPTCP_DSS_ACK32 4
#define TCPOLEN_MPTCP_DSS_ACK64 8
@@ -106,6 +107,7 @@ struct mptcp_subflow_context {
u64 remote_key;
u64 idsn;
u64 map_seq;
+ u32 snd_isn;
u32 token;
u32 rel_write_seq;
u32 map_subflow_seq;
