tcp.h

00001 /*
00002  * Copyright (c) 2013-2017, Arm Limited and affiliates.
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License");
00006  * you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  *     http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS,
00013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 
00018 #ifndef TCP_H_
00019 #define TCP_H_
00020 
00021 
00022 #define TCP_UNACK_MAX 3
00023 #define TCP_WINDOW_SIZE 300
00024 #define TCP_ETHERNET_WINDOW_SIZE 1440
00025 #define TCP_TIMER_PERIOD 150 // milliseconds
00026 
00027 #define TCP_LOWPAN_MSS_LIMIT 300
00028 
00029 #define TCP_MAX_RX_QLEN 1024
00030 
00031 // Times in TCP_TIMER_PERIOD units
00032 #define TCP_TIME_WAIT_TO_CLOSE 1600     // 4 minutes
00033 #define TCP_FIN_WAIT_2_TIMEOUT 500      // 75s
00034 #define TCP_MINIMUM_RTO 8               // 1.05s + 1 tick round-up
00035 #define TCP_INITIAL_RTO 8               // 1.05s (RFC6298) + 1 tick round-up
00036 #define TCP_INITIAL_CONSERVATIVE_RTO 21 // 3s + 1 tick round-up
00037 #define TCP_MAXIMUM_RTO 400             // 1 minute
00038 #define TCP_MAX_RETRIES 6               // if min RTO, 1s+2s+4s+8s+16s+32s(+60s wait) = 123s - RFC1122 says at least 100 seconds
00039 #define TCP_SYN_RETRIES 7               // retry at 1s+2s+4s+8s+16s+32s+60s(+60s wait)  = 3 min 3s - RFC1122 says at least 3 minutes
00040 #define TCP_PROBLEM_RETRIES 3           // report connection difficulties - RFC1122 says at least 3 retries
00041 
00042 // maximum RTO should be kept below 4000 to avoid 16-bit calculation overflow
00043 
00044 #define TCP_FLAG_FIN 1
00045 #define TCP_FLAG_SYN 2
00046 #define TCP_FLAG_RST 4
00047 #define TCP_FLAG_PSH 8
00048 #define TCP_FLAG_ACK 16
00049 #define TCP_FLAG_URG 32
00050 #define TCP_FLAG_ECE 64
00051 #define TCP_FLAG_CWR 128
00052 
00053 #define TCP_OPTION_END 0
00054 #define TCP_OPTION_NOP 1
00055 #define TCP_OPTION_MSS 2
00056 
00057 // State numbering must remain fixed, as TCP test API uses it,
00058 // and we don't expose it in public headers. The chosen
00059 // numbering is from the SNMP MIB - RFC 4022.
00060 #define TCP_STATE_CLOSED        1
00061 #define TCP_STATE_LISTEN        2
00062 #define TCP_STATE_SYN_SENT      3
00063 #define TCP_STATE_SYN_RECEIVED  4
00064 #define TCP_STATE_ESTABLISHED   5
00065 #define TCP_STATE_FIN_WAIT_1    6
00066 #define TCP_STATE_FIN_WAIT_2    7
00067 #define TCP_STATE_CLOSE_WAIT    8
00068 #define TCP_STATE_LAST_ACK      9
00069 #define TCP_STATE_CLOSING       10
00070 #define TCP_STATE_TIME_WAIT     11
00071 #define TCP_STATES              12
00072 
00073 struct inet_pcb_s;
00074 
00075 typedef enum tcp_error_ {
00076 
00077     TCP_ERROR_NO_ERROR,
00078     TCP_ERROR_BUFFER_ALLOCATION_ERROR,
00079     TCP_ERROR_SOCKET_ALLOCATION_ERROR,
00080     TCP_ERROR_SOCKET_NOT_FOUND,
00081     TCP_ERROR_SECURE_ALLOCATION_ERROR,
00082     TCP_ERROR_WRONG_STATE,
00083     TCP_ERROR_ADDR_SELECTION,
00084     TCP_SESSION_REMOVED
00085 
00086 } tcp_error;
00087 
00088 typedef struct tcp_session_t {
00089     struct inet_pcb_s *inet_pcb;
00090     protocol_interface_info_entry_t *interface;
00091     uint32_t   send_unacknowledged;
00092     uint32_t   send_next;
00093     uint32_t   send_wl1;        // segment seq number at last window update
00094     uint32_t   send_wl2;        // segment ack number at last window update
00095     uint16_t   send_window;
00096     uint16_t   send_mss_peer;   // peer's advertised mss (RFC 5681 RMSS)
00097     uint16_t   send_mss_eff;    // effective send MSS (RFC 1122 Eff.snd.MSS, RFC 5681 SMSS)
00098     uint16_t   receive_mss;
00099     uint32_t   receive_next;    // sequence number
00100     uint32_t   receive_adv;     // advertised window right edge
00101     uint16_t   timer;
00102     uint8_t    retry;
00103     bool       passive_open : 1;
00104     uint8_t    state;
00105     bool       busy : 1;
00106     bool       persist : 1;
00107     bool       sent_fin : 1;
00108     uint16_t   rto;
00109     int16_t    srtt8;       // these should go into destination cache
00110     int16_t    srttvar4;
00111 } tcp_session_t;
00112 
00113 #ifdef NO_TCP
00114 NS_DUMMY_DEFINITIONS_OK
00115 #undef TCP_TEST
00116 #define tcp_info(pcb) ((struct tcp_session_t *)NULL)
00117 #define tcp_buf_save(buf) (buf)
00118 #define tcp_up(buf) buffer_free(buf)
00119 #define tcp_session_ptr_allocate(socket_id) ((tcp_session_t*) NULL)
00120 #define tcp_socket_released(tcp_info) ((void) 0)
00121 #define tcp_state_name(tcp_session) "NO_TCP"
00122 #define tcp_handle_time_event(tickUpdate) ((void) 0)
00123 #define tcp_session_data_received(tcp_info)  ((void) 0)
00124 #define tcp_session_close(tcp_info) TCP_ERROR_SOCKET_NOT_FOUND
00125 #define tcp_session_shutdown_read(tcp_info) TCP_ERROR_SOCKET_NOT_FOUND
00126 #else
00127 #define tcp_info(pcb) ((struct tcp_session_t *)((pcb)->session))
00128 extern tcp_error tcp_session_open(tcp_session_t *tcp_session);
00129 extern tcp_error tcp_session_close(tcp_session_t *tcp_session);
00130 extern tcp_error tcp_session_shutdown_read(tcp_session_t *tcp_session);
00131 extern tcp_error tcp_session_abort(tcp_session_t *tcp_session);
00132 extern tcp_error tcp_session_send(tcp_session_t *tcp_info, buffer_t *buf);
00133 extern void tcp_session_data_received(tcp_session_t *tcp_info);
00134 extern buffer_t *tcp_up(buffer_t *buf);
00135 extern tcp_session_t *tcp_session_ptr_allocate(struct inet_pcb_s *inet_pcb, tcp_session_t *from_time_wait);
00136 extern tcp_session_t *tcp_session_ptr_free(tcp_session_t *tcp_info);
00137 extern void tcp_socket_released(tcp_session_t *tcp_info);
00138 const char *tcp_state_name(const tcp_session_t *tcp_info);
00139 
00140 /**
00141  * \brief Function used for handling time events.
00142  */
00143 
00144 extern void tcp_handle_time_event(uint16_t tickUpdate);
00145 #endif // NO_TCP
00146 
00147 #ifdef TCP_TEST
00148 extern int8_t tcp_test_drop_tx(int state, uint8_t count);
00149 extern int8_t tcp_test_drop_rx(int state, uint8_t count);
00150 extern void tcp_test_drop_reset(void);
00151 #else
00152 #define tcp_test_drop_tx(state, count) ((int8_t) -1)
00153 #define tcp_test_drop_rx(state, codunt) ((int8_t) -1)
00154 #define tcp_test_drop_reset() ((void) 0)
00155 #endif
00156 
00157 #endif /* TCP_H_ */