1 /** 2 * @file 3 * TCP protocol definitions 4 */ 5 6 /* 7 * Copyright (c) 2001-2004 Swedish Institute of Computer Science. 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without modification, 11 * are permitted provided that the following conditions are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright notice, 14 * this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 3. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 22 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 24 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 26 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 29 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 30 * OF SUCH DAMAGE. 31 * 32 * This file is part of the lwIP TCP/IP stack. 33 * 34 * Author: Adam Dunkels <adam@sics.se> 35 * 36 */ 37 #ifndef LWIP_HDR_PROT_TCP_H 38 #define LWIP_HDR_PROT_TCP_H 39 40 #include "lwip/arch.h" 41 42 #ifdef __cplusplus 43 extern "C" { 44 #endif 45 46 /* Length of the TCP header, excluding options. */ 47 #define TCP_HLEN 20 48 49 /* Fields are (of course) in network byte order. 50 * Some fields are converted to host byte order in tcp_input(). 51 */ 52 #ifdef PACK_STRUCT_USE_INCLUDES 53 # include "arch/bpstruct.h" 54 #endif 55 PACK_STRUCT_BEGIN 56 struct tcp_hdr { 57 PACK_STRUCT_FIELD(u16_t src); 58 PACK_STRUCT_FIELD(u16_t dest); 59 PACK_STRUCT_FIELD(u32_t seqno); 60 PACK_STRUCT_FIELD(u32_t ackno); 61 PACK_STRUCT_FIELD(u16_t _hdrlen_rsvd_flags); 62 PACK_STRUCT_FIELD(u16_t wnd); 63 PACK_STRUCT_FIELD(u16_t chksum); 64 PACK_STRUCT_FIELD(u16_t urgp); 65 } PACK_STRUCT_STRUCT; 66 PACK_STRUCT_END 67 #ifdef PACK_STRUCT_USE_INCLUDES 68 # include "arch/epstruct.h" 69 #endif 70 71 /* TCP header flags bits */ 72 #define TCP_FIN 0x01U 73 #define TCP_SYN 0x02U 74 #define TCP_RST 0x04U 75 #define TCP_PSH 0x08U 76 #define TCP_ACK 0x10U 77 #define TCP_URG 0x20U 78 #define TCP_ECE 0x40U 79 #define TCP_CWR 0x80U 80 /* Valid TCP header flags */ 81 #define TCP_FLAGS 0x3fU 82 83 #define TCP_MAX_OPTION_BYTES 40 84 85 #define TCPH_HDRLEN(phdr) ((u16_t)(lwip_ntohs((phdr)->_hdrlen_rsvd_flags) >> 12)) 86 #define TCPH_HDRLEN_BYTES(phdr) ((u8_t)(TCPH_HDRLEN(phdr) << 2)) 87 #define TCPH_FLAGS(phdr) ((u8_t)((lwip_ntohs((phdr)->_hdrlen_rsvd_flags) & TCP_FLAGS))) 88 89 #define TCPH_HDRLEN_SET(phdr, len) (phdr)->_hdrlen_rsvd_flags = lwip_htons(((len) << 12) | TCPH_FLAGS(phdr)) 90 #define TCPH_FLAGS_SET(phdr, flags) (phdr)->_hdrlen_rsvd_flags = (((phdr)->_hdrlen_rsvd_flags & PP_HTONS(~TCP_FLAGS)) | lwip_htons(flags)) 91 #define TCPH_HDRLEN_FLAGS_SET(phdr, len, flags) (phdr)->_hdrlen_rsvd_flags = (u16_t)(lwip_htons((u16_t)((len) << 12) | (flags))) 92 93 #define TCPH_SET_FLAG(phdr, flags ) (phdr)->_hdrlen_rsvd_flags = ((phdr)->_hdrlen_rsvd_flags | lwip_htons(flags)) 94 #define TCPH_UNSET_FLAG(phdr, flags) (phdr)->_hdrlen_rsvd_flags = ((phdr)->_hdrlen_rsvd_flags & ~lwip_htons(flags)) 95 96 #ifdef __cplusplus 97 } 98 #endif 99 100 #endif /* LWIP_HDR_PROT_TCP_H */ 101