1 /* 2 * Fundamental constants relating to TCP Protocol 3 * 4 * Copyright (C) 1999-2019, Broadcom. 5 * 6 * Unless you and Broadcom execute a separate written software license 7 * agreement governing use of this software, this software is licensed to you 8 * under the terms of the GNU General Public License version 2 (the "GPL"), 9 * available at http://www.broadcom.com/licenses/GPLv2.php, with the 10 * following added to such license: 11 * 12 * As a special exception, the copyright holders of this software give you 13 * permission to link this software with independent modules, and to copy and 14 * distribute the resulting executable under terms of your choice, provided that 15 * you also meet, for each linked independent module, the terms and conditions 16 * of the license of that module. An independent module is a module which is 17 * not derived from this software. The special exception does not apply to any 18 * modifications of the software. 19 * 20 * Notwithstanding the above, under no circumstances may you combine this 21 * software in any way with any other Broadcom software provided under a license 22 * other than the GPL, without Broadcom's express prior written consent. 23 * 24 * 25 * <<Broadcom-WL-IPTag/Open:>> 26 * 27 * $Id: bcmtcp.h 700076 2017-05-17 14:42:22Z $ 28 */ 29 30 #ifndef _bcmtcp_h_ 31 #define _bcmtcp_h_ 32 33 #ifndef _TYPEDEFS_H_ 34 #include <typedefs.h> 35 #endif // endif 36 37 /* This marks the start of a packed structure section. */ 38 #include <packed_section_start.h> 39 40 #define TCP_SRC_PORT_OFFSET 0 /* TCP source port offset */ 41 #define TCP_DEST_PORT_OFFSET 2 /* TCP dest port offset */ 42 #define TCP_SEQ_NUM_OFFSET 4 /* TCP sequence number offset */ 43 #define TCP_ACK_NUM_OFFSET 8 /* TCP acknowledgement number offset */ 44 #define TCP_HLEN_OFFSET 12 /* HLEN and reserved bits offset */ 45 #define TCP_FLAGS_OFFSET 13 /* FLAGS and reserved bits offset */ 46 #define TCP_CHKSUM_OFFSET 16 /* TCP body checksum offset */ 47 48 #define TCP_PORT_LEN 2 /* TCP port field length */ 49 50 /* 8bit TCP flag field */ 51 #define TCP_FLAG_URG 0x20 52 #define TCP_FLAG_ACK 0x10 53 #define TCP_FLAG_PSH 0x08 54 #define TCP_FLAG_RST 0x04 55 #define TCP_FLAG_SYN 0x02 56 #define TCP_FLAG_FIN 0x01 57 58 #define TCP_HLEN_MASK 0xf000 59 #define TCP_HLEN_SHIFT 12 60 61 /* These fields are stored in network order */ 62 BWL_PRE_PACKED_STRUCT struct bcmtcp_hdr { 63 uint16 src_port; /* Source Port Address */ 64 uint16 dst_port; /* Destination Port Address */ 65 uint32 seq_num; /* TCP Sequence Number */ 66 uint32 ack_num; /* TCP Sequence Number */ 67 uint16 hdrlen_rsvd_flags; /* Header length, reserved bits and flags */ 68 uint16 tcpwin; /* TCP window */ 69 uint16 chksum; /* Segment checksum with pseudoheader */ 70 uint16 urg_ptr; /* Points to seq-num of byte following urg data */ 71 } BWL_POST_PACKED_STRUCT; 72 73 #define TCP_MIN_HEADER_LEN 20 74 75 #define TCP_HDRLEN_MASK 0xf0 76 #define TCP_HDRLEN_SHIFT 4 77 #define TCP_HDRLEN(hdrlen) (((hdrlen)&TCP_HDRLEN_MASK) >> TCP_HDRLEN_SHIFT) 78 79 #define TCP_FLAGS_MASK 0x1f 80 #define TCP_FLAGS(hdrlen) ((hdrlen)&TCP_FLAGS_MASK) 81 82 /* This marks the end of a packed structure section. */ 83 #include <packed_section_end.h> 84 85 /* To address round up by 32bit. */ 86 #define IS_TCPSEQ_GE(a, b) ((a - b) < NBITVAL(31)) /* a >= b */ 87 #define IS_TCPSEQ_LE(a, b) ((b - a) < NBITVAL(31)) /* a =< b */ 88 #define IS_TCPSEQ_GT(a, b) !IS_TCPSEQ_LE(a, b) /* a > b */ 89 #define IS_TCPSEQ_LT(a, b) !IS_TCPSEQ_GE(a, b) /* a < b */ 90 91 #endif /* #ifndef _bcmtcp_h_ */ 92