diff options
Diffstat (limited to 'net/mptcp/subflow.c')
-rw-r--r-- | net/mptcp/subflow.c | 117 |
1 files changed, 82 insertions, 35 deletions
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 6042a47da6..c330946384 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -20,6 +20,7 @@ #include <net/transp_v6.h> #endif #include <net/mptcp.h> + #include "protocol.h" #include "mib.h" @@ -99,6 +100,7 @@ static struct mptcp_sock *subflow_token_join_request(struct request_sock *req) return NULL; } subflow_req->local_id = local_id; + subflow_req->request_bkup = mptcp_pm_is_backup(msk, (struct sock_common *)req); return msk; } @@ -150,8 +152,10 @@ static int subflow_check_req(struct request_sock *req, /* no MPTCP if MD5SIG is enabled on this socket or we may run out of * TCP option space. */ - if (rcu_access_pointer(tcp_sk(sk_listener)->md5sig_info)) + if (rcu_access_pointer(tcp_sk(sk_listener)->md5sig_info)) { + subflow_add_reset_reason(skb, MPTCP_RST_EMPTCP); return -EINVAL; + } #endif mptcp_get_options(skb, &mp_opt); @@ -165,6 +169,9 @@ static int subflow_check_req(struct request_sock *req, return 0; } else if (opt_mp_join) { SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINSYNRX); + + if (mp_opt.backup) + SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINSYNBACKUPRX); } if (opt_mp_capable && listener->request_mptcp) { @@ -219,6 +226,7 @@ again: ntohs(inet_sk((struct sock *)subflow_req->msk)->inet_sport)); if (!mptcp_pm_sport_in_anno_list(subflow_req->msk, sk_listener)) { SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MISMATCHPORTSYNRX); + subflow_add_reset_reason(skb, MPTCP_RST_EPROHIBIT); return -EPERM; } SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINPORTSYNRX); @@ -227,10 +235,12 @@ again: subflow_req_create_thmac(subflow_req); if (unlikely(req->syncookie)) { - if (mptcp_can_accept_new_subflow(subflow_req->msk)) - subflow_init_req_cookie_join_save(subflow_req, skb); - else + if (!mptcp_can_accept_new_subflow(subflow_req->msk)) { + subflow_add_reset_reason(skb, MPTCP_RST_EPROHIBIT); return -EPERM; + } + + subflow_init_req_cookie_join_save(subflow_req, skb); } pr_debug("token=%u, remote_nonce=%u msk=%p", subflow_req->token, @@ -281,10 +291,21 @@ int mptcp_subflow_init_cookie_req(struct request_sock *req, } EXPORT_SYMBOL_GPL(mptcp_subflow_init_cookie_req); +static enum sk_rst_reason mptcp_get_rst_reason(const struct sk_buff *skb) +{ + const struct mptcp_ext *mpext = mptcp_get_ext(skb); + + if (!mpext) + return SK_RST_REASON_NOT_SPECIFIED; + + return sk_rst_convert_mptcp_reason(mpext->reset_reason); +} + static struct dst_entry *subflow_v4_route_req(const struct sock *sk, struct sk_buff *skb, struct flowi *fl, - struct request_sock *req) + struct request_sock *req, + u32 tw_isn) { struct dst_entry *dst; int err; @@ -292,7 +313,7 @@ static struct dst_entry *subflow_v4_route_req(const struct sock *sk, tcp_rsk(req)->is_mptcp = 1; subflow_init_req(req, sk); - dst = tcp_request_sock_ipv4_ops.route_req(sk, skb, fl, req); + dst = tcp_request_sock_ipv4_ops.route_req(sk, skb, fl, req, tw_isn); if (!dst) return NULL; @@ -302,7 +323,8 @@ static struct dst_entry *subflow_v4_route_req(const struct sock *sk, dst_release(dst); if (!req->syncookie) - tcp_request_sock_ops.send_reset(sk, skb); + tcp_request_sock_ops.send_reset(sk, skb, + mptcp_get_rst_reason(skb)); return NULL; } @@ -351,7 +373,8 @@ static int subflow_v6_send_synack(const struct sock *sk, struct dst_entry *dst, static struct dst_entry *subflow_v6_route_req(const struct sock *sk, struct sk_buff *skb, struct flowi *fl, - struct request_sock *req) + struct request_sock *req, + u32 tw_isn) { struct dst_entry *dst; int err; @@ -359,7 +382,7 @@ static struct dst_entry *subflow_v6_route_req(const struct sock *sk, tcp_rsk(req)->is_mptcp = 1; subflow_init_req(req, sk); - dst = tcp_request_sock_ipv6_ops.route_req(sk, skb, fl, req); + dst = tcp_request_sock_ipv6_ops.route_req(sk, skb, fl, req, tw_isn); if (!dst) return NULL; @@ -369,7 +392,8 @@ static struct dst_entry *subflow_v6_route_req(const struct sock *sk, dst_release(dst); if (!req->syncookie) - tcp6_request_sock_ops.send_reset(sk, skb); + tcp6_request_sock_ops.send_reset(sk, skb, + mptcp_get_rst_reason(skb)); return NULL; } #endif @@ -405,7 +429,7 @@ void mptcp_subflow_reset(struct sock *ssk) /* must hold: tcp_done() could drop last reference on parent */ sock_hold(sk); - tcp_send_active_reset(ssk, GFP_ATOMIC); + mptcp_send_active_reset_reason(ssk); tcp_done(ssk); if (!test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &mptcp_sk(sk)->flags)) mptcp_schedule_work(sk); @@ -557,6 +581,9 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb) subflow->mp_join = 1; MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKRX); + if (subflow->backup) + MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKBACKUPRX); + if (subflow_use_different_dport(msk, sk)) { pr_debug("synack inet_dport=%d %d", ntohs(inet_sk(sk)->inet_dport), @@ -594,6 +621,8 @@ static int subflow_chk_local_id(struct sock *sk) return err; subflow_set_local_id(subflow, err); + subflow->request_bkup = mptcp_pm_is_backup(msk, (struct sock_common *)sk); + return 0; } @@ -774,6 +803,7 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk, struct mptcp_subflow_request_sock *subflow_req; struct mptcp_options_received mp_opt; bool fallback, fallback_is_fatal; + enum sk_rst_reason reason; struct mptcp_sock *owner; struct sock *child; @@ -873,13 +903,18 @@ create_child: ntohs(inet_sk((struct sock *)owner)->inet_sport)); if (!mptcp_pm_sport_in_anno_list(owner, sk)) { SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MISMATCHPORTACKRX); + subflow_add_reset_reason(skb, MPTCP_RST_EPROHIBIT); goto dispose_child; } SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINPORTACKRX); } - if (!mptcp_finish_join(child)) + if (!mptcp_finish_join(child)) { + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(child); + + subflow_add_reset_reason(skb, subflow->reset_reason); goto dispose_child; + } SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKRX); tcp_rsk(req)->drop_req = true; @@ -887,7 +922,7 @@ create_child: } /* check for expected invariant - should never trigger, just help - * catching eariler subtle bugs + * catching earlier subtle bugs */ WARN_ON_ONCE(child && *own_req && tcp_sk(child)->is_mptcp && (!mptcp_subflow_ctx(child) || @@ -899,7 +934,8 @@ dispose_child: tcp_rsk(req)->drop_req = true; inet_csk_prepare_for_destroy_sock(child); tcp_done(child); - req->rsk_ops->send_reset(sk, skb); + reason = mptcp_get_rst_reason(skb); + req->rsk_ops->send_reset(sk, skb, reason); /* The last child reference will be released by the caller */ return child; @@ -1092,6 +1128,8 @@ static enum mapping_status get_mapping_status(struct sock *ssk, } if (mpext->data_fin == 1) { + u64 data_fin_seq; + if (data_len == 1) { bool updated = mptcp_update_rcv_data_fin(msk, mpext->data_seq, mpext->dsn64); @@ -1104,26 +1142,26 @@ static enum mapping_status get_mapping_status(struct sock *ssk, */ skb_ext_del(skb, SKB_EXT_MPTCP); return MAPPING_OK; - } else { - if (updated) - mptcp_schedule_work((struct sock *)msk); - - return MAPPING_DATA_FIN; } - } else { - u64 data_fin_seq = mpext->data_seq + data_len - 1; - /* If mpext->data_seq is a 32-bit value, data_fin_seq - * must also be limited to 32 bits. - */ - if (!mpext->dsn64) - data_fin_seq &= GENMASK_ULL(31, 0); + if (updated) + mptcp_schedule_work((struct sock *)msk); - mptcp_update_rcv_data_fin(msk, data_fin_seq, mpext->dsn64); - pr_debug("DATA_FIN with mapping seq=%llu dsn64=%d", - data_fin_seq, mpext->dsn64); + return MAPPING_DATA_FIN; } + data_fin_seq = mpext->data_seq + data_len - 1; + + /* If mpext->data_seq is a 32-bit value, data_fin_seq must also + * be limited to 32 bits. + */ + if (!mpext->dsn64) + data_fin_seq &= GENMASK_ULL(31, 0); + + mptcp_update_rcv_data_fin(msk, data_fin_seq, mpext->dsn64); + pr_debug("DATA_FIN with mapping seq=%llu dsn64=%d", + data_fin_seq, mpext->dsn64); + /* Adjust for DATA_FIN using 1 byte of sequence space */ data_len--; } @@ -1192,14 +1230,22 @@ static void mptcp_subflow_discard_data(struct sock *ssk, struct sk_buff *skb, { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); bool fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN; - u32 incr; + struct tcp_sock *tp = tcp_sk(ssk); + u32 offset, incr, avail_len; - incr = limit >= skb->len ? skb->len + fin : limit; + offset = tp->copied_seq - TCP_SKB_CB(skb)->seq; + if (WARN_ON_ONCE(offset > skb->len)) + goto out; - pr_debug("discarding=%d len=%d seq=%d", incr, skb->len, - subflow->map_subflow_seq); + avail_len = skb->len - offset; + incr = limit >= avail_len ? avail_len + fin : limit; + + pr_debug("discarding=%d len=%d offset=%d seq=%d", incr, skb->len, + offset, subflow->map_subflow_seq); MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DUPDATA); tcp_sk(ssk)->copied_seq += incr; + +out: if (!before(tcp_sk(ssk)->copied_seq, TCP_SKB_CB(skb)->end_seq)) sk_eat_skb(ssk, skb); if (mptcp_subflow_get_map_offset(subflow) >= subflow->map_data_len) @@ -1234,7 +1280,7 @@ static void mptcp_subflow_fail(struct mptcp_sock *msk, struct sock *ssk) struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); unsigned long fail_tout; - /* greceful failure can happen only on the MPC subflow */ + /* graceful failure can happen only on the MPC subflow */ if (WARN_ON_ONCE(ssk != READ_ONCE(msk->first))) return; @@ -1336,7 +1382,7 @@ reset: tcp_set_state(ssk, TCP_CLOSE); while ((skb = skb_peek(&ssk->sk_receive_queue))) sk_eat_skb(ssk, skb); - tcp_send_active_reset(ssk, GFP_ATOMIC); + mptcp_send_active_reset_reason(ssk); WRITE_ONCE(subflow->data_avail, false); return false; } @@ -1976,6 +2022,7 @@ static void subflow_ulp_clone(const struct request_sock *req, new_ctx->fully_established = 1; new_ctx->remote_key_valid = 1; new_ctx->backup = subflow_req->backup; + new_ctx->request_bkup = subflow_req->request_bkup; WRITE_ONCE(new_ctx->remote_id, subflow_req->remote_id); new_ctx->token = subflow_req->token; new_ctx->thmac = subflow_req->thmac; |