common/src/nx_tcp_packet_send_control.c (netxduo)

/**************************************************************************/ /* */ /* Copyright (c) Microsoft Corporation. All rights reserved. */ /* */ /* This software is licensed under the Microsoft Software License */ /* Terms for Microsoft Azure RTOS. Full text of the license can be */ /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */ /* and in the root directory of this software. */ /* */ /**************************************************************************/ /**************************************************************************/ /**************************************************************************/ /** */ /** NetX Component */ /** */ /** Transmission Control Protocol (TCP) */ /** */ /**************************************************************************/ /**************************************************************************/ #define NX_SOURCE_CODE /* Include necessary system files. */ #include "nx_api.h" #include "nx_ip.h" #ifdef FEATURE_NX_IPV6 #include "nx_ipv6.h" #endif /* FEATURE_NX_IPV6 */ #include "nx_packet.h" #include "nx_tcp.h" #ifdef NX_IPSEC_ENABLE #include "nx_ipsec.h" #endif /* NX_IPSEC_ENABLE */ /**************************************************************************/ /* */ /* FUNCTION RELEASE */ /* */ /* _nx_tcp_packet_send_ack PORTABLE C */ /* 6.1 */ /* AUTHOR */ /* */ /* Yuxin Zhou, Microsoft Corporation */ /* */ /* DESCRIPTION */ /* */ /* This function sends a TCP control packet from the specified socket. */ /* */ /* INPUT */ /* */ /* socket_ptr Pointer to socket */ /* control_bits TCP control bits */ /* tx_sequence Transmit sequence number */ /* ack_number Transmit acknowledge number */ /* data Data of zero window probe */ /* */ /* OUTPUT */ /* */ /* None */ /* */ /* CALLS */ /* */ /* _nx_packet_allocate Allocate a packet */ /* _nx_ip_checksum_compute Calculate TCP checksum */ /* _nx_ip_packet_send Send IPv4 packet */ /* _nx_ipv6_packet_send Send IPv6 packet */ /* */ /* CALLED BY */ /* */ /* _nx_tcp_packet_send_syn Send SYN packet */ /* _nx_tcp_packet_send_ack Send ACK packet */ /* _nx_tcp_packet_send_fin Send FIN packet */ /* _nx_tcp_packet_send_rst Send RST packet */ /* _nx_tcp_packet_send_probe Send zero window probe packet */ /* */ /* RELEASE HISTORY */ /* */ /* DATE NAME DESCRIPTION */ /* */ /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */ /* 09-30-2020 Yuxin Zhou Modified comment(s), */ /* resulting in version 6.1 */ /* */ /**************************************************************************/ VOID _nx_tcp_packet_send_control(NX_TCP_SOCKET *socket_ptr, ULONG control_bits, ULONG tx_sequence, ULONG ack_number, ULONG option_word_1, ULONG option_word_2, UCHAR *data) { NX_IP *ip_ptr; NX_PACKET *packet_ptr; NX_TCP_HEADER *tcp_header_ptr; ULONG checksum; ULONG data_offset = 0; ULONG *source_ip = NX_NULL, *dest_ip = NX_NULL; #if defined(NX_DISABLE_TCP_TX_CHECKSUM) || defined(NX_ENABLE_INTERFACE_CAPABILITY) || defined(NX_IPSEC_ENABLE) UINT compute_checksum = 1; #endif /* defined(NX_DISABLE_TCP_TX_CHECKSUM) || defined(NX_ENABLE_INTERFACE_CAPABILITY) || defined(NX_IPSEC_ENABLE) */ ULONG header_size; ULONG window_size; #ifdef NX_DISABLE_TCP_TX_CHECKSUM compute_checksum = 0; #endif /* NX_DISABLE_TCP_TX_CHECKSUM */ /* Setup the IP pointer. */ ip_ptr = socket_ptr -> nx_tcp_socket_ip_ptr; if (control_bits & NX_TCP_SYN_BIT) { /* Set header size. */ header_size = NX_TCP_SYN_HEADER; window_size = socket_ptr -> nx_tcp_socket_rx_window_current; } else { /* Set header size. */ header_size = NX_TCP_HEADER_SIZE; /* Set window size. */ #ifdef NX_ENABLE_TCP_WINDOW_SCALING window_size = socket_ptr -> nx_tcp_socket_rx_window_current >> socket_ptr -> nx_tcp_rcv_win_scale_value; #else window_size = socket_ptr -> nx_tcp_socket_rx_window_current; #endif /* NX_ENABLE_TCP_WINDOW_SCALING */ } #ifdef NX_ENABLE_TCP_WINDOW_SCALING /* Make sure the window_size is less than 0xFFFF. */ if (window_size > 0xFFFF) { window_size = 0xFFFF; } #endif /* NX_ENABLE_TCP_WINDOW_SCALING */ #ifdef NX_IPSEC_ENABLE /* Get data offset from socket directly. */ data_offset = socket_ptr -> nx_tcp_socket_egress_sa_data_offset; #endif /* NX_IPSEC_ENABLE */ #ifdef NX_ENABLE_DUAL_PACKET_POOL /* Allocate from auxiliary packet pool first. */ if (_nx_packet_allocate(ip_ptr -> nx_ip_auxiliary_packet_pool, &packet_ptr, NX_IP_PACKET + data_offset, NX_NO_WAIT)) { if (ip_ptr -> nx_ip_auxiliary_packet_pool != ip_ptr -> nx_ip_default_packet_pool) #endif /* NX_ENABLE_DUAL_PACKET_POOL */ { /*lint -e{835} -e{845} suppress operating on zero. */ if (_nx_packet_allocate(ip_ptr -> nx_ip_default_packet_pool, &packet_ptr, NX_IP_PACKET + data_offset, NX_NO_WAIT) != NX_SUCCESS) { /* Just give up and return. */ return; } } #ifdef NX_ENABLE_DUAL_PACKET_POOL else { /* Just give up and return. */ return; } } #endif /* NX_ENABLE_DUAL_PACKET_POOL */ /* Check to see if the packet has enough room to fill with the max TCP header (SYN + probe data). */ if ((UINT)(packet_ptr -> nx_packet_data_end - packet_ptr -> nx_packet_prepend_ptr) < (NX_TCP_SYN_SIZE + 1)) { /* Error getting packet, so just get out! */ _nx_packet_release(packet_ptr); return; } /*lint -e{644} suppress variable might not be initialized, since "packet_ptr" was initialized in _nx_packet_allocate. */ packet_ptr -> nx_packet_ip_version = (UCHAR)(socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_version); /* Allocate a packet for the control message. */ #ifndef NX_DISABLE_IPV4 if (socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_version == NX_IP_VERSION_V4) { /* The outgoing interface should have been stored in the socket structure. */ packet_ptr -> nx_packet_address.nx_packet_interface_ptr = socket_ptr -> nx_tcp_socket_connect_interface; } #endif /* !NX_DISABLE_IPV4 */ /* Add debug information. */ NX_PACKET_DEBUG(__FILE__, __LINE__, packet_ptr); #ifdef NX_IPSEC_ENABLE packet_ptr -> nx_packet_ipsec_sa_ptr = socket_ptr -> nx_tcp_socket_egress_sa; #endif /* Setup the packet payload pointers and length for a basic TCP packet. */ packet_ptr -> nx_packet_append_ptr = packet_ptr -> nx_packet_prepend_ptr + sizeof(NX_TCP_HEADER); /* Setup the packet length. */ packet_ptr -> nx_packet_length = sizeof(NX_TCP_HEADER); /* Pickup the pointer to the head of the TCP packet. */ /*lint -e{927} -e{826} suppress cast of pointer to pointer, since it is necessary */ tcp_header_ptr = (NX_TCP_HEADER *)packet_ptr -> nx_packet_prepend_ptr; /* Build the control request in the TCP header. */ tcp_header_ptr -> nx_tcp_header_word_0 = (((ULONG)(socket_ptr -> nx_tcp_socket_port)) << NX_SHIFT_BY_16) | (ULONG)socket_ptr -> nx_tcp_socket_connect_port; tcp_header_ptr -> nx_tcp_sequence_number = tx_sequence; tcp_header_ptr -> nx_tcp_acknowledgment_number = ack_number; tcp_header_ptr -> nx_tcp_header_word_3 = header_size | control_bits | window_size; tcp_header_ptr -> nx_tcp_header_word_4 = 0; /* Remember the last ACKed sequence and the last reported window size. */ socket_ptr -> nx_tcp_socket_rx_sequence_acked = ack_number; socket_ptr -> nx_tcp_socket_rx_window_last_sent = socket_ptr -> nx_tcp_socket_rx_window_current; /* Endian swapping logic. If NX_LITTLE_ENDIAN is specified, these macros will swap the endian of the TCP header. */ NX_CHANGE_ULONG_ENDIAN(tcp_header_ptr -> nx_tcp_header_word_0); NX_CHANGE_ULONG_ENDIAN(tcp_header_ptr -> nx_tcp_sequence_number); NX_CHANGE_ULONG_ENDIAN(tcp_header_ptr -> nx_tcp_acknowledgment_number); NX_CHANGE_ULONG_ENDIAN(tcp_header_ptr -> nx_tcp_header_word_3); NX_CHANGE_ULONG_ENDIAN(tcp_header_ptr -> nx_tcp_header_word_4); /* Check whether or not data is set. */ if (data) { /* Zero window probe data exist. */ *packet_ptr -> nx_packet_append_ptr++ = *data; packet_ptr -> nx_packet_length++; } /* Whether it is a SYN packet. */ if (control_bits & NX_TCP_SYN_BIT) { /* Endian swapping logic. If NX_LITTLE_ENDIAN is specified, these macros will swap the endian of the TCP header. */ NX_CHANGE_ULONG_ENDIAN(option_word_1); NX_CHANGE_ULONG_ENDIAN(option_word_2); /* Set options. */ /*lint --e{927} --e{826} suppress cast of pointer to pointer, since it is necessary */ *((ULONG *)packet_ptr -> nx_packet_append_ptr) = option_word_1; *(((ULONG *)packet_ptr -> nx_packet_append_ptr) + 1) = option_word_2; /* Adjust packet information. */ packet_ptr -> nx_packet_append_ptr += (sizeof(ULONG) << 1); packet_ptr -> nx_packet_length += (ULONG)(sizeof(ULONG) << 1); } #ifdef NX_ENABLE_INTERFACE_CAPABILITY if (socket_ptr -> nx_tcp_socket_connect_interface -> nx_interface_capability_flag & NX_INTERFACE_CAPABILITY_TCP_TX_CHECKSUM) { compute_checksum = 0; } #endif /* NX_ENABLE_INTERFACE_CAPABILITY */ #ifdef NX_IPSEC_ENABLE if ((packet_ptr -> nx_packet_ipsec_sa_ptr != NX_NULL) && (((NX_IPSEC_SA *)(packet_ptr -> nx_packet_ipsec_sa_ptr)) -> nx_ipsec_sa_encryption_method != NX_CRYPTO_NONE)) { compute_checksum = 1; } #endif /* NX_IPSEC_ENABLE */ #if defined(NX_DISABLE_TCP_TX_CHECKSUM) || defined(NX_ENABLE_INTERFACE_CAPABILITY) || defined(NX_IPSEC_ENABLE) if (compute_checksum) #endif /* defined(NX_DISABLE_TCP_TX_CHECKSUM ) || defined(NX_ENABLE_INTERFACE_CAPABILITY) || defined(NX_IPSEC_ENABLE) */ { /* Set the packet source IP address. */ #ifndef NX_DISABLE_IPV4 if (socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_version == NX_IP_VERSION_V4) { /* For IPv4 the IP instance has only one global address. */ source_ip = &socket_ptr -> nx_tcp_socket_connect_interface -> nx_interface_ip_address; /* Set the destination address to the other side of the TCP connection. */ dest_ip = &socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_address.v4; } #endif /* !NX_DISABLE_IPV4 */ #ifdef FEATURE_NX_IPV6 if (socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_version == NX_IP_VERSION_V6) { /* For IPv6, use the source address specified in the socket outgoing interface. */ source_ip = socket_ptr -> nx_tcp_socket_ipv6_addr -> nxd_ipv6_address; /* Set the destination address to the other side of the TCP connection. */ dest_ip = socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_address.v6; } #endif /* FEATURE_NX_IPV6 */ /* Calculate the TCP checksum. */ checksum = _nx_ip_checksum_compute(packet_ptr, NX_PROTOCOL_TCP, (UINT)packet_ptr -> nx_packet_length, source_ip, dest_ip); checksum = ~checksum & NX_LOWER_16_MASK; /* Move the checksum into header. */ NX_CHANGE_ULONG_ENDIAN(tcp_header_ptr -> nx_tcp_header_word_4); tcp_header_ptr -> nx_tcp_header_word_4 = (checksum << NX_SHIFT_BY_16); NX_CHANGE_ULONG_ENDIAN(tcp_header_ptr -> nx_tcp_header_word_4); } #ifdef NX_ENABLE_INTERFACE_CAPABILITY else { packet_ptr -> nx_packet_interface_capability_flag |= NX_INTERFACE_CAPABILITY_TCP_TX_CHECKSUM; } #endif /* NX_ENABLE_INTERFACE_CAPABILITY */ #ifndef NX_DISABLE_IPV4 /* Send the TCP packet to the IP component. */ if (socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_version == NX_IP_VERSION_V4) { _nx_ip_packet_send(ip_ptr, packet_ptr, socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_address.v4, socket_ptr -> nx_tcp_socket_type_of_service, socket_ptr -> nx_tcp_socket_time_to_live, NX_IP_TCP, socket_ptr -> nx_tcp_socket_fragment_enable, socket_ptr -> nx_tcp_socket_next_hop_address); } #endif /* !NX_DISABLE_IPV4 */ #ifdef FEATURE_NX_IPV6 if (socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_version == NX_IP_VERSION_V6) { /* The IPv6 packet interface must be set before sending. Set to the TCP socket outgoing interface. */ packet_ptr -> nx_packet_address.nx_packet_ipv6_address_ptr = socket_ptr -> nx_tcp_socket_ipv6_addr; _nx_ipv6_packet_send(ip_ptr, packet_ptr, NX_PROTOCOL_TCP, packet_ptr -> nx_packet_length, ip_ptr -> nx_ipv6_hop_limit, socket_ptr -> nx_tcp_socket_ipv6_addr -> nxd_ipv6_address, socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_address.v6); } #endif /* FEATURE_NX_IPV6 */ }

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