int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, const struct dccp_hdr *dh, const unsigned len) { struct dccp_sock *dp = dccp_sk(sk); if (dccp_check_seqno(sk, skb)) goto discard; if (dccp_parse_options(sk, skb)) goto discard; if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) dccp_event_ack_recv(sk, skb); if (dccp_msk(sk)->dccpms_send_ack_vector && dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_ACKVEC_STATE_RECEIVED)) goto discard; ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb); ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb); return __dccp_rcv_established(sk, skb, dh, len); discard: __kfree_skb(skb); return 0; }
int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, const struct dccp_hdr *dh, const unsigned len) { struct dccp_sock *dp = dccp_sk(sk); if (dccp_check_seqno(sk, skb)) goto discard; if (dccp_parse_options(sk, skb)) goto discard; if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) dccp_event_ack_recv(sk, skb); if (dccp_msk(sk)->dccpms_send_ack_vector && dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_ACKVEC_STATE_RECEIVED)) goto discard; /* * Deliver to the CCID module in charge. * FIXME: Currently DCCP operates one-directional only, i.e. a listening * server is not at the same time a connecting client. There is * not much sense in delivering to both rx/tx sides at the moment * (only one is active at a time); when moving to bidirectional * service, this needs to be revised. */ if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER) ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb); else ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb); return __dccp_rcv_established(sk, skb, dh, len); discard: __kfree_skb(skb); return 0; }
int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, struct dccp_hdr *dh, unsigned len) { struct dccp_sock *dp = dccp_sk(sk); struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); const int old_state = sk->sk_state; int queued = 0; /* * Step 3: Process LISTEN state * * If S.state == LISTEN, * If P.type == Request or P contains a valid Init Cookie option, * (* Must scan the packet's options to check for Init * Cookies. Only Init Cookies are processed here, * however; other options are processed in Step 8. This * scan need only be performed if the endpoint uses Init * Cookies *) * (* Generate a new socket and switch to that socket *) * Set S := new socket for this port pair * S.state = RESPOND * Choose S.ISS (initial seqno) or set from Init Cookies * Initialize S.GAR := S.ISS * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init * Cookies Continue with S.state == RESPOND * (* A Response packet will be generated in Step 11 *) * Otherwise, * Generate Reset(No Connection) unless P.type == Reset * Drop packet and return */ if (sk->sk_state == DCCP_LISTEN) { if (dh->dccph_type == DCCP_PKT_REQUEST) { if (inet_csk(sk)->icsk_af_ops->conn_request(sk, skb) < 0) return 1; /* FIXME: do congestion control initialization */ goto discard; } if (dh->dccph_type == DCCP_PKT_RESET) goto discard; /* Caller (dccp_v4_do_rcv) will send Reset */ dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION; return 1; } if (sk->sk_state != DCCP_REQUESTING) { if (dccp_check_seqno(sk, skb)) goto discard; /* * Step 8: Process options and mark acknowledgeable */ if (dccp_parse_options(sk, skb)) goto discard; if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) dccp_event_ack_recv(sk, skb); if (dccp_msk(sk)->dccpms_send_ack_vector && dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_ACKVEC_STATE_RECEIVED)) goto discard; /* XXX see the comments in dccp_rcv_established about this */ if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER) ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb); else ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb); } /* * Step 9: Process Reset * If P.type == Reset, * Tear down connection * S.state := TIMEWAIT * Set TIMEWAIT timer * Drop packet and return */ if (dh->dccph_type == DCCP_PKT_RESET) { /* * Queue the equivalent of TCP fin so that dccp_recvmsg * exits the loop */ dccp_fin(sk, skb); dccp_time_wait(sk, DCCP_TIME_WAIT, 0); return 0; /* * Step 7: Check for unexpected packet types * If (S.is_server and P.type == CloseReq) * or (S.is_server and P.type == Response) * or (S.is_client and P.type == Request) * or (S.state == RESPOND and P.type == Data), * Send Sync packet acknowledging P.seqno * Drop packet and return */ } else if ((dp->dccps_role != DCCP_ROLE_CLIENT && (dh->dccph_type == DCCP_PKT_RESPONSE || dh->dccph_type == DCCP_PKT_CLOSEREQ)) || (dp->dccps_role == DCCP_ROLE_CLIENT && dh->dccph_type == DCCP_PKT_REQUEST) || (sk->sk_state == DCCP_RESPOND && dh->dccph_type == DCCP_PKT_DATA)) { dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNC); goto discard; } else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) { dccp_rcv_closereq(sk, skb); goto discard; } else if (dh->dccph_type == DCCP_PKT_CLOSE) { dccp_rcv_close(sk, skb); return 0; } if (unlikely(dh->dccph_type == DCCP_PKT_SYNC)) { dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNCACK); goto discard; } switch (sk->sk_state) { case DCCP_CLOSED: dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION; return 1; case DCCP_REQUESTING: /* FIXME: do congestion control initialization */ queued = dccp_rcv_request_sent_state_process(sk, skb, dh, len); if (queued >= 0) return queued; __kfree_skb(skb); return 0; case DCCP_RESPOND: case DCCP_PARTOPEN: queued = dccp_rcv_respond_partopen_state_process(sk, skb, dh, len); break; } if (dh->dccph_type == DCCP_PKT_ACK || dh->dccph_type == DCCP_PKT_DATAACK) { switch (old_state) { case DCCP_PARTOPEN: sk->sk_state_change(sk); sk_wake_async(sk, 0, POLL_OUT); break; } } if (!queued) { discard: __kfree_skb(skb); } return 0; }