mptcp: add csum_reqd in mptcp_out_options

This patch added a new member csum_reqd in struct mptcp_out_options and
struct mptcp_subflow_request_sock. Initialized it with the helper
function mptcp_is_checksum_enabled().

In mptcp_write_options, if this field is enabled, send out the MP_CAPABLE
suboption with the MPTCP_CAP_CHECKSUM_REQD flag.

Acked-by: Paolo Abeni <pabeni@redhat.com>
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>

diff --git a/include/net/mptcp.h b/include/net/mptcp.h
index 23bbd439e1152d22aa3d8f94151bbf8b40f720b9..33af68eea96f2700464f9d7b6b8911aca2152087 100644 (file)
--- a/include/net/mptcp.h
+++ b/include/net/mptcp.h
@@ -64,8 +64,9 @@ struct mptcp_out_options {
        struct mptcp_rm_list rm_list;
        u8 join_id;
        u8 backup;
-       u8 reset_reason:4;
-       u8 reset_transient:1;
+       u8 reset_reason:4,
+          reset_transient:1,
+          csum_reqd:1;
        u32 nonce;
        u64 thmac;
        u32 token;

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 6b825fb3fa8322ef4fd96a7a92d02c4ec2bb6628..bb3a1f3b6e99f83dfff4a96fbe08607c05387984 100644 (file)
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -380,6 +380,7 @@ bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
        subflow->snd_isn = TCP_SKB_CB(skb)->end_seq;
        if (subflow->request_mptcp) {
                opts->suboptions = OPTION_MPTCP_MPC_SYN;
+               opts->csum_reqd = mptcp_is_checksum_enabled(sock_net(sk));
                *size = TCPOLEN_MPTCP_MPC_SYN;
                return true;
        } else if (subflow->request_join) {
@@ -435,6 +436,7 @@ static bool mptcp_established_options_mp(struct sock *sk, struct sk_buff *skb,
                                         struct mptcp_out_options *opts)
 {
        struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
+       struct mptcp_sock *msk = mptcp_sk(subflow->conn);
        struct mptcp_ext *mpext;
        unsigned int data_len;
 
@@ -465,6 +467,7 @@ static bool mptcp_established_options_mp(struct sock *sk, struct sk_buff *skb,
                opts->suboptions = OPTION_MPTCP_MPC_ACK;
                opts->sndr_key = subflow->local_key;
                opts->rcvr_key = subflow->remote_key;
+               opts->csum_reqd = READ_ONCE(msk->csum_enabled);
 
                /* Section 3.1.
                 * The MP_CAPABLE option is carried on the SYN, SYN/ACK, and ACK
@@ -789,6 +792,7 @@ bool mptcp_synack_options(const struct request_sock *req, unsigned int *size,
        if (subflow_req->mp_capable) {
                opts->suboptions = OPTION_MPTCP_MPC_SYNACK;
                opts->sndr_key = subflow_req->local_key;
+               opts->csum_reqd = subflow_req->csum_reqd;
                *size = TCPOLEN_MPTCP_MPC_SYNACK;
                pr_debug("subflow_req=%p, local_key=%llu",
                         subflow_req, subflow_req->local_key);
@@ -1123,7 +1127,7 @@ void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp,
 {
        if ((OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK |
             OPTION_MPTCP_MPC_ACK) & opts->suboptions) {
-               u8 len;
+               u8 len, flag = MPTCP_CAP_HMAC_SHA256;
 
                if (OPTION_MPTCP_MPC_SYN & opts->suboptions)
                        len = TCPOLEN_MPTCP_MPC_SYN;
@@ -1134,9 +1138,12 @@ void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp,
                else
                        len = TCPOLEN_MPTCP_MPC_ACK;
 
+               if (opts->csum_reqd)
+                       flag |= MPTCP_CAP_CHECKSUM_REQD;
+
                *ptr++ = mptcp_option(MPTCPOPT_MP_CAPABLE, len,
                                      MPTCP_SUPPORTED_VERSION,
-                                     MPTCP_CAP_HMAC_SHA256);
+                                     flag);
 
                if (!((OPTION_MPTCP_MPC_SYNACK | OPTION_MPTCP_MPC_ACK) &
                    opts->suboptions))

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 4913ac7b6d199b10aecd1f6fe0c49b7b6dc83b7d..09e94726e030ee03c1f624ffec5defaee2369f95 100644 (file)
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -347,7 +347,8 @@ struct mptcp_subflow_request_sock {
        struct  tcp_request_sock sk;
        u16     mp_capable : 1,
                mp_join : 1,
-               backup : 1;
+               backup : 1,
+               csum_reqd : 1;
        u8      local_id;
        u8      remote_id;
        u64     local_key;

diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 33956337c46bc3fa0d4b5dc77090ba7a8b335b1f..45acab63c387eed807549c57e5361ca86443bf4c 100644 (file)
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -108,6 +108,7 @@ static void subflow_init_req(struct request_sock *req, const struct sock *sk_lis
 
        subflow_req->mp_capable = 0;
        subflow_req->mp_join = 0;
+       subflow_req->csum_reqd = mptcp_is_checksum_enabled(sock_net(sk_listener));
        subflow_req->msk = NULL;
        mptcp_token_init_request(req);
 }