@@ -65,7 +65,8 @@ struct mptcp_out_options {
u8 join_id;
u8 backup;
u8 reset_reason:4;
- u8 reset_transient:1;
+ u8 reset_transient:1,
+ csum_reqd:1;
u32 nonce;
u64 thmac;
u32 token;
@@ -381,6 +381,7 @@ 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) {
@@ -436,6 +437,7 @@ 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;
@@ -466,6 +468,7 @@ 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
@@ -793,6 +796,7 @@ 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);
@@ -1127,7 +1131,7 @@ 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;
@@ -1138,9 +1142,12 @@ 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))
@@ -346,7 +346,8 @@ 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;
@@ -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);
}