mptcp: add rm_list in mptcp_out_options

This patch defined a new struct mptcp_rm_list, the ids field was an
array of the removing address ids, the nr field was the valid number of
removing address ids in the array. The array size was definced as a new
macro MPTCP_RM_IDS_MAX. Changed the member rm_id of struct
mptcp_out_options to rm_list.

In mptcp_established_options_rm_addr, invoked mptcp_pm_rm_addr_signal to
get the rm_list. According the number of addresses in it, calculated
the padded RM_ADDR suboption length. And saved the ids array in struct
mptcp_out_options's rm_list member.

In mptcp_write_options, iterated each address id from struct
mptcp_out_options's rm_list member, set the invalid ones as TCPOPT_NOP,
then filled them into the RM_ADDR suboption.

Changed TCPOLEN_MPTCP_RM_ADDR_BASE from 4 to 3.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 27 insertions, 8 deletions

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 444a38681e93..e74d0513187f 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -674,20 +674,25 @@ static bool mptcp_established_options_rm_addr(struct sock *sk,
 {
 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
 	struct mptcp_sock *msk = mptcp_sk(subflow->conn);
-	u8 rm_id;
+	struct mptcp_rm_list rm_list;
+	int i, len;
 
 	if (!mptcp_pm_should_rm_signal(msk) ||
-	    !(mptcp_pm_rm_addr_signal(msk, remaining, &rm_id)))
+	    !(mptcp_pm_rm_addr_signal(msk, remaining, &rm_list)))
 		return false;
 
-	if (remaining < TCPOLEN_MPTCP_RM_ADDR_BASE)
+	len = mptcp_rm_addr_len(&rm_list);
+	if (len < 0)
+		return false;
+	if (remaining < len)
 		return false;
 
-	*size = TCPOLEN_MPTCP_RM_ADDR_BASE;
+	*size = len;
 	opts->suboptions |= OPTION_MPTCP_RM_ADDR;
-	opts->rm_id = rm_id;
+	opts->rm_list = rm_list;
 
-	pr_debug("rm_id=%d", opts->rm_id);
+	for (i = 0; i < opts->rm_list.nr; i++)
+		pr_debug("rm_list_ids[%d]=%d", i, opts->rm_list.ids[i]);
 
 	return true;
 }
@@ -1217,9 +1222,23 @@ mp_capable_done:
 	}
 
 	if (OPTION_MPTCP_RM_ADDR & opts->suboptions) {
+		u8 i = 1;
+
 		*ptr++ = mptcp_option(MPTCPOPT_RM_ADDR,
-				      TCPOLEN_MPTCP_RM_ADDR_BASE,
-				      0, opts->rm_id);
+				      TCPOLEN_MPTCP_RM_ADDR_BASE + opts->rm_list.nr,
+				      0, opts->rm_list.ids[0]);
+
+		while (i < opts->rm_list.nr) {
+			u8 id1, id2, id3, id4;
+
+			id1 = opts->rm_list.ids[i];
+			id2 = i + 1 < opts->rm_list.nr ? opts->rm_list.ids[i + 1] : TCPOPT_NOP;
+			id3 = i + 2 < opts->rm_list.nr ? opts->rm_list.ids[i + 2] : TCPOPT_NOP;
+			id4 = i + 3 < opts->rm_list.nr ? opts->rm_list.ids[i + 3] : TCPOPT_NOP;
+			put_unaligned_be32(id1 << 24 | id2 << 16 | id3 << 8 | id4, ptr);
+			ptr += 1;
+			i += 4;
+		}
 	}
 
 	if (OPTION_MPTCP_PRIO & opts->suboptions) {