/* * FreeRTOS+TCP V3.1.0 * Copyright (C) 2022 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * SPDX-License-Identifier: MIT * * Permission is hereby granted, free of charge, to any person obtaining a copy of * this software and associated documentation files (the "Software"), to deal in * the Software without restriction, including without limitation the rights to * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of * the Software, and to permit persons to whom the Software is furnished to do so, * subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * http://aws.amazon.com/freertos * http://www.FreeRTOS.org */ #ifndef FREERTOS_TCP_IP_H #define FREERTOS_TCP_IP_H /* *INDENT-OFF* */ #ifdef __cplusplus extern "C" { #endif /* *INDENT-ON* */ BaseType_t xProcessReceivedTCPPacket( NetworkBufferDescriptor_t * pxDescriptor ); typedef enum eTCP_STATE { /* Comments about the TCP states are borrowed from the very useful * Wiki page: * http://en.wikipedia.org/wiki/Transmission_Control_Protocol */ eCLOSED = 0U, /* 0 (server + client) no connection state at all. */ eTCP_LISTEN, /* 1 (server) waiting for a connection request * from any remote TCP and port. */ eCONNECT_SYN, /* 2 (client) internal state: socket wants to send * a connect */ eSYN_FIRST, /* 3 (server) Just created, must ACK the SYN request. */ eSYN_RECEIVED, /* 4 (server) waiting for a confirming connection request * acknowledgement after having both received and sent a connection request. */ eESTABLISHED, /* 5 (server + client) an open connection, data received can be * delivered to the user. The normal state for the data transfer phase of the connection. */ eFIN_WAIT_1, /* 6 (server + client) waiting for a connection termination request from the remote TCP, * or an acknowledgement of the connection termination request previously sent. */ eFIN_WAIT_2, /* 7 (server + client) waiting for a connection termination request from the remote TCP. */ eCLOSE_WAIT, /* 8 (server + client) waiting for a connection termination request from the local user. */ eCLOSING, /* 9 (server + client) waiting for a connection termination request acknowledgement from the remote TCP. */ eLAST_ACK, /*10 (server + client) waiting for an acknowledgement of the connection termination request * previously sent to the remote TCP * (which includes an acknowledgement of its connection termination request). */ eTIME_WAIT, /*11 (either server or client) waiting for enough time to pass to be sure the remote TCP received the * acknowledgement of its connection termination request. [According to RFC 793 a connection can * stay in TIME-WAIT for a maximum of four minutes known as a MSL (maximum segment lifetime).] */ } eIPTCPState_t; /* * The meaning of the TCP flags: */ #define tcpTCP_FLAG_FIN ( ( uint8_t ) 0x01U ) /**< No more data from sender. */ #define tcpTCP_FLAG_SYN ( ( uint8_t ) 0x02U ) /**< Synchronize sequence numbers. */ #define tcpTCP_FLAG_RST ( ( uint8_t ) 0x04U ) /**< Reset the connection. */ #define tcpTCP_FLAG_PSH ( ( uint8_t ) 0x08U ) /**< Push function: please push buffered data to the recv application. */ #define tcpTCP_FLAG_ACK ( ( uint8_t ) 0x10U ) /**< Acknowledgment field is significant. */ #define tcpTCP_FLAG_URG ( ( uint8_t ) 0x20U ) /**< Urgent pointer field is significant. */ #define tcpTCP_FLAG_ECN ( ( uint8_t ) 0x40U ) /**< ECN-Echo. */ #define tcpTCP_FLAG_CWR ( ( uint8_t ) 0x80U ) /**< Congestion Window Reduced. */ #define tcpTCP_FLAG_CTRL ( ( uint8_t ) 0x1FU ) /**< A mask to filter all protocol flags. */ /* * A few values of the TCP options: */ #define tcpTCP_OPT_END 0U /**< End of TCP options list. */ #define tcpTCP_OPT_NOOP 1U /**< "No-operation" TCP option. */ #define tcpTCP_OPT_MSS 2U /**< Maximum segment size TCP option. */ #define tcpTCP_OPT_WSOPT 3U /**< TCP Window Scale Option (3-byte long). */ #define tcpTCP_OPT_SACK_P 4U /**< Advertise that SACK is permitted. */ #define tcpTCP_OPT_SACK_A 5U /**< SACK option with first/last. */ #define tcpTCP_OPT_TIMESTAMP 8U /**< Time-stamp option. */ #define tcpTCP_OPT_MSS_LEN 4U /**< Length of TCP MSS option. */ #define tcpTCP_OPT_WSOPT_LEN 3U /**< Length of TCP WSOPT option. */ #define tcpTCP_OPT_TIMESTAMP_LEN 10 /**< fixed length of the time-stamp option. */ /** @brief * Minimum segment length as outlined by RFC 791 section 3.1. * Minimum segment length ( 536 ) = Minimum MTU ( 576 ) - IP Header ( 20 ) - TCP Header ( 20 ). */ #define tcpMINIMUM_SEGMENT_LENGTH 536U /** @brief * The macro tcpNOW_CONNECTED() is use to determine if the connection makes a * transition from connected to non-connected and vice versa. * tcpNOW_CONNECTED() returns true when the status has one of these values: * eESTABLISHED, eFIN_WAIT_1, eFIN_WAIT_2, eCLOSING, eLAST_ACK, eTIME_WAIT * Technically the connection status is closed earlier, but the library wants * to prevent that the socket will be deleted before the last ACK has been * and thus causing a 'RST' packet on either side. */ #define tcpNOW_CONNECTED( status ) \ ( ( ( ( status ) >= ( BaseType_t ) eESTABLISHED ) && ( ( status ) != ( BaseType_t ) eCLOSE_WAIT ) ) ? 1 : 0 ) /** @brief * The highest 4 bits in the TCP offset byte indicate the total length of the * TCP header, divided by 4. */ #define tcpVALID_BITS_IN_TCP_OFFSET_BYTE ( 0xF0U ) /* * Acknowledgements to TCP data packets may be delayed as long as more is being expected. * A normal delay would be 200ms. Here a much shorter delay of 20 ms is being used to * gain performance. */ #define tcpDELAYED_ACK_SHORT_DELAY_MS ( 2 ) /**< Should not become smaller than 1. */ #define tcpDELAYED_ACK_LONGER_DELAY_MS ( 20 ) /**< Longer delay for ACK. */ /** @brief * The MSS (Maximum Segment Size) will be taken as large as possible. However, packets with * an MSS of 1460 bytes won't be transported through the internet. The MSS will be reduced * to 1400 bytes. */ #define tcpREDUCED_MSS_THROUGH_INTERNET ( 1400 ) /** @brief * When there are no TCP options, the TCP offset equals 20 bytes, which is stored as * the number 5 (words) in the higher nibble of the TCP-offset byte. */ #define tcpTCP_OFFSET_LENGTH_BITS ( 0xf0U ) #define tcpTCP_OFFSET_STANDARD_LENGTH ( 0x50U ) /**< Standard TCP packet offset. */ /** @brief * Each TCP socket is checked regularly to see if it can send data packets. * By default, the maximum number of packets sent during one check is limited to 8. * This amount may be further limited by setting the socket's TX window size. */ #if ( !defined( SEND_REPEATED_COUNT ) ) #define SEND_REPEATED_COUNT ( 8 ) #endif /* !defined( SEND_REPEATED_COUNT ) */ /** @brief * Define a maximum period of time (ms) to leave a TCP-socket unattended. * When a TCP timer expires, retries and keep-alive messages will be checked. */ #ifndef tcpMAXIMUM_TCP_WAKEUP_TIME_MS #define tcpMAXIMUM_TCP_WAKEUP_TIME_MS 20000U #endif /* Two macro's that were introduced to work with both IPv4 and IPv6. */ #define xIPHeaderSize( pxNetworkBuffer ) ( ipSIZE_OF_IPv4_HEADER ) /**< Size of IP Header. */ #define uxIPHeaderSizeSocket( pxSocket ) ( ipSIZE_OF_IPv4_HEADER ) /**< Size of IP Header socket. */ /* *INDENT-OFF* */ #ifdef __cplusplus } /* extern "C" */ #endif /* *INDENT-ON* */ #endif /* FREERTOS_TCP_IP_H */