1 /*************************************************************************** 2 * Copyright (c) 2024 Microsoft Corporation 3 * 4 * This program and the accompanying materials are made available under the 5 * terms of the MIT License which is available at 6 * https://opensource.org/licenses/MIT. 7 * 8 * SPDX-License-Identifier: MIT 9 **************************************************************************/ 10 11 12 /**************************************************************************/ 13 /**************************************************************************/ 14 /** */ 15 /** NetX Secure Component */ 16 /** */ 17 /** Datagram Transport Layer Security (DTLS) */ 18 /** */ 19 /**************************************************************************/ 20 /**************************************************************************/ 21 22 #define NX_SECURE_SOURCE_CODE 23 24 #include "nx_secure_dtls.h" 25 26 #ifdef NX_SECURE_ENABLE_DTLS 27 #include "nx_packet.h" 28 29 /**************************************************************************/ 30 /* */ 31 /* FUNCTION RELEASE */ 32 /* */ 33 /* _nx_secure_dtls_retransmit_queue_flush PORTABLE C */ 34 /* 6.1.10 */ 35 /* AUTHOR */ 36 /* */ 37 /* Timothy Stapko, Microsoft Corporation */ 38 /* */ 39 /* DESCRIPTION */ 40 /* */ 41 /* This function flushes the DTLS transmit queue when the appropriate */ 42 /* response is received from the remote host, clearing out the */ 43 /* previously-sent flight, resetting the queue for the next flight. */ 44 /* */ 45 /* INPUT */ 46 /* */ 47 /* dtls_session DTLS control block */ 48 /* */ 49 /* OUTPUT */ 50 /* */ 51 /* None */ 52 /* */ 53 /* CALLS */ 54 /* */ 55 /* nx_secure_tls_packet_release Release packet */ 56 /* tx_mutex_get Get protection mutex */ 57 /* tx_mutex_put Put protection mutex */ 58 /* */ 59 /* CALLED BY */ 60 /* */ 61 /* _nx_secure_dtls_client_handshake DTLS client state machine */ 62 /* _nx_secure_dtls_server_handshake DTLS server state machine */ 63 /* _nx_secure_dtls_session_start Actual DTLS session start call*/ 64 /* */ 65 /* RELEASE HISTORY */ 66 /* */ 67 /* DATE NAME DESCRIPTION */ 68 /* */ 69 /* 05-19-2020 Timothy Stapko Initial Version 6.0 */ 70 /* 09-30-2020 Timothy Stapko Modified comment(s), */ 71 /* released packet securely, */ 72 /* resulting in version 6.1 */ 73 /* 01-31-2022 Timothy Stapko Modified comment(s), */ 74 /* fixed packet leak, */ 75 /* resulting in version 6.1.10 */ 76 /* */ 77 /**************************************************************************/ _nx_secure_dtls_retransmit_queue_flush(NX_SECURE_DTLS_SESSION * dtls_session)78VOID _nx_secure_dtls_retransmit_queue_flush(NX_SECURE_DTLS_SESSION *dtls_session) 79 { 80 TX_INTERRUPT_SAVE_AREA 81 NX_PACKET *packet_ptr; 82 NX_PACKET *next_packet_ptr; 83 84 85 /* Get the protection. */ 86 tx_mutex_get(&_nx_secure_tls_protection, TX_WAIT_FOREVER); 87 88 /* Setup packet pointer. */ 89 packet_ptr = dtls_session -> nx_secure_dtls_transmit_sent_head; 90 91 /* Clear the head and the tail pointers. */ 92 dtls_session -> nx_secure_dtls_transmit_sent_head = NX_NULL; 93 dtls_session -> nx_secure_dtls_transmit_sent_tail = NX_NULL; 94 95 /* Loop to clear all the packets out. */ 96 while (packet_ptr && 97 (packet_ptr != (NX_PACKET *)NX_PACKET_ENQUEUED)) 98 { 99 100 /* Disable interrupts. */ 101 TX_DISABLE 102 103 /* Pickup the next queued packet. */ 104 next_packet_ptr = packet_ptr -> nx_packet_union_next.nx_packet_tcp_queue_next; 105 106 /* Mark the packet as no longer being in a TCP queue. */ 107 /*lint -e{923} suppress cast of ULONG to pointer. */ 108 packet_ptr -> nx_packet_union_next.nx_packet_tcp_queue_next = (NX_PACKET *)NX_PACKET_ALLOCATED; 109 110 /* Has the packet been transmitted? */ 111 if (packet_ptr -> nx_packet_queue_next == ((NX_PACKET *)NX_DRIVER_TX_DONE)) 112 { 113 114 /* Yes, the driver has already released the packet. */ 115 116 /* Restore interrupts. */ 117 TX_RESTORE 118 119 /* Release the packet. */ 120 nx_secure_tls_packet_release(packet_ptr); 121 } 122 else 123 { 124 125 /* Restore interrupts. */ 126 TX_RESTORE 127 } 128 129 /* Move to the next packet. */ 130 packet_ptr = next_packet_ptr; 131 132 /* Decrease the queued packet count. */ 133 dtls_session -> nx_secure_dtls_transmit_sent_count--; 134 } 135 136 /* Release the protection before suspending on event. */ 137 tx_mutex_put(&_nx_secure_tls_protection); 138 } 139 #endif /* NX_SECURE_ENABLE_DTLS */ 140 141
