Atsushi Hattori / Mbed 2 deprecated 20210627_Logger

hattori&ide

Dependencies:   mbed

TinyHTTP/EthernetNetIf/LPC1768/lwip/netif/ppp/vj.h@0:f77369cabd75, 18 months ago (annotated)

Committer:
hattori_atsushi
Date:
Sun Dec 18 08:16:01 2022 +0000
Revision:
0:f77369cabd75
hattori

Who changed what in which revision?

UserRevisionLine numberNew contents of line
hattori_atsushi 0:f77369cabd75 1 /*
hattori_atsushi 0:f77369cabd75 2 * Definitions for tcp compression routines.
hattori_atsushi 0:f77369cabd75 3 *
hattori_atsushi 0:f77369cabd75 4 * $Id: vj.h,v 1.7 2010/02/22 17:52:09 goldsimon Exp $
hattori_atsushi 0:f77369cabd75 5 *
hattori_atsushi 0:f77369cabd75 6 * Copyright (c) 1989 Regents of the University of California.
hattori_atsushi 0:f77369cabd75 7 * All rights reserved.
hattori_atsushi 0:f77369cabd75 8 *
hattori_atsushi 0:f77369cabd75 9 * Redistribution and use in source and binary forms are permitted
hattori_atsushi 0:f77369cabd75 10 * provided that the above copyright notice and this paragraph are
hattori_atsushi 0:f77369cabd75 11 * duplicated in all such forms and that any documentation,
hattori_atsushi 0:f77369cabd75 12 * advertising materials, and other materials related to such
hattori_atsushi 0:f77369cabd75 13 * distribution and use acknowledge that the software was developed
hattori_atsushi 0:f77369cabd75 14 * by the University of California, Berkeley. The name of the
hattori_atsushi 0:f77369cabd75 15 * University may not be used to endorse or promote products derived
hattori_atsushi 0:f77369cabd75 16 * from this software without specific prior written permission.
hattori_atsushi 0:f77369cabd75 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
hattori_atsushi 0:f77369cabd75 18 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
hattori_atsushi 0:f77369cabd75 19 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
hattori_atsushi 0:f77369cabd75 20 *
hattori_atsushi 0:f77369cabd75 21 * Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
hattori_atsushi 0:f77369cabd75 22 * - Initial distribution.
hattori_atsushi 0:f77369cabd75 23 */
hattori_atsushi 0:f77369cabd75 24
hattori_atsushi 0:f77369cabd75 25 #ifndef VJ_H
hattori_atsushi 0:f77369cabd75 26 #define VJ_H
hattori_atsushi 0:f77369cabd75 27
hattori_atsushi 0:f77369cabd75 28 #include "lwip/ip.h"
hattori_atsushi 0:f77369cabd75 29 #include "lwip/tcp_impl.h"
hattori_atsushi 0:f77369cabd75 30
hattori_atsushi 0:f77369cabd75 31 #define MAX_SLOTS 16 /* must be > 2 and < 256 */
hattori_atsushi 0:f77369cabd75 32 #define MAX_HDR 128
hattori_atsushi 0:f77369cabd75 33
hattori_atsushi 0:f77369cabd75 34 /*
hattori_atsushi 0:f77369cabd75 35 * Compressed packet format:
hattori_atsushi 0:f77369cabd75 36 *
hattori_atsushi 0:f77369cabd75 37 * The first octet contains the packet type (top 3 bits), TCP
hattori_atsushi 0:f77369cabd75 38 * 'push' bit, and flags that indicate which of the 4 TCP sequence
hattori_atsushi 0:f77369cabd75 39 * numbers have changed (bottom 5 bits). The next octet is a
hattori_atsushi 0:f77369cabd75 40 * conversation number that associates a saved IP/TCP header with
hattori_atsushi 0:f77369cabd75 41 * the compressed packet. The next two octets are the TCP checksum
hattori_atsushi 0:f77369cabd75 42 * from the original datagram. The next 0 to 15 octets are
hattori_atsushi 0:f77369cabd75 43 * sequence number changes, one change per bit set in the header
hattori_atsushi 0:f77369cabd75 44 * (there may be no changes and there are two special cases where
hattori_atsushi 0:f77369cabd75 45 * the receiver implicitly knows what changed -- see below).
hattori_atsushi 0:f77369cabd75 46 *
hattori_atsushi 0:f77369cabd75 47 * There are 5 numbers which can change (they are always inserted
hattori_atsushi 0:f77369cabd75 48 * in the following order): TCP urgent pointer, window,
hattori_atsushi 0:f77369cabd75 49 * acknowlegement, sequence number and IP ID. (The urgent pointer
hattori_atsushi 0:f77369cabd75 50 * is different from the others in that its value is sent, not the
hattori_atsushi 0:f77369cabd75 51 * change in value.) Since typical use of SLIP links is biased
hattori_atsushi 0:f77369cabd75 52 * toward small packets (see comments on MTU/MSS below), changes
hattori_atsushi 0:f77369cabd75 53 * use a variable length coding with one octet for numbers in the
hattori_atsushi 0:f77369cabd75 54 * range 1 - 255 and 3 octets (0, MSB, LSB) for numbers in the
hattori_atsushi 0:f77369cabd75 55 * range 256 - 65535 or 0. (If the change in sequence number or
hattori_atsushi 0:f77369cabd75 56 * ack is more than 65535, an uncompressed packet is sent.)
hattori_atsushi 0:f77369cabd75 57 */
hattori_atsushi 0:f77369cabd75 58
hattori_atsushi 0:f77369cabd75 59 /*
hattori_atsushi 0:f77369cabd75 60 * Packet types (must not conflict with IP protocol version)
hattori_atsushi 0:f77369cabd75 61 *
hattori_atsushi 0:f77369cabd75 62 * The top nibble of the first octet is the packet type. There are
hattori_atsushi 0:f77369cabd75 63 * three possible types: IP (not proto TCP or tcp with one of the
hattori_atsushi 0:f77369cabd75 64 * control flags set); uncompressed TCP (a normal IP/TCP packet but
hattori_atsushi 0:f77369cabd75 65 * with the 8-bit protocol field replaced by an 8-bit connection id --
hattori_atsushi 0:f77369cabd75 66 * this type of packet syncs the sender & receiver); and compressed
hattori_atsushi 0:f77369cabd75 67 * TCP (described above).
hattori_atsushi 0:f77369cabd75 68 *
hattori_atsushi 0:f77369cabd75 69 * LSB of 4-bit field is TCP "PUSH" bit (a worthless anachronism) and
hattori_atsushi 0:f77369cabd75 70 * is logically part of the 4-bit "changes" field that follows. Top
hattori_atsushi 0:f77369cabd75 71 * three bits are actual packet type. For backward compatibility
hattori_atsushi 0:f77369cabd75 72 * and in the interest of conserving bits, numbers are chosen so the
hattori_atsushi 0:f77369cabd75 73 * IP protocol version number (4) which normally appears in this nibble
hattori_atsushi 0:f77369cabd75 74 * means "IP packet".
hattori_atsushi 0:f77369cabd75 75 */
hattori_atsushi 0:f77369cabd75 76
hattori_atsushi 0:f77369cabd75 77 /* packet types */
hattori_atsushi 0:f77369cabd75 78 #define TYPE_IP 0x40
hattori_atsushi 0:f77369cabd75 79 #define TYPE_UNCOMPRESSED_TCP 0x70
hattori_atsushi 0:f77369cabd75 80 #define TYPE_COMPRESSED_TCP 0x80
hattori_atsushi 0:f77369cabd75 81 #define TYPE_ERROR 0x00
hattori_atsushi 0:f77369cabd75 82
hattori_atsushi 0:f77369cabd75 83 /* Bits in first octet of compressed packet */
hattori_atsushi 0:f77369cabd75 84 #define NEW_C 0x40 /* flag bits for what changed in a packet */
hattori_atsushi 0:f77369cabd75 85 #define NEW_I 0x20
hattori_atsushi 0:f77369cabd75 86 #define NEW_S 0x08
hattori_atsushi 0:f77369cabd75 87 #define NEW_A 0x04
hattori_atsushi 0:f77369cabd75 88 #define NEW_W 0x02
hattori_atsushi 0:f77369cabd75 89 #define NEW_U 0x01
hattori_atsushi 0:f77369cabd75 90
hattori_atsushi 0:f77369cabd75 91 /* reserved, special-case values of above */
hattori_atsushi 0:f77369cabd75 92 #define SPECIAL_I (NEW_S|NEW_W|NEW_U) /* echoed interactive traffic */
hattori_atsushi 0:f77369cabd75 93 #define SPECIAL_D (NEW_S|NEW_A|NEW_W|NEW_U) /* unidirectional data */
hattori_atsushi 0:f77369cabd75 94 #define SPECIALS_MASK (NEW_S|NEW_A|NEW_W|NEW_U)
hattori_atsushi 0:f77369cabd75 95
hattori_atsushi 0:f77369cabd75 96 #define TCP_PUSH_BIT 0x10
hattori_atsushi 0:f77369cabd75 97
hattori_atsushi 0:f77369cabd75 98
hattori_atsushi 0:f77369cabd75 99 /*
hattori_atsushi 0:f77369cabd75 100 * "state" data for each active tcp conversation on the wire. This is
hattori_atsushi 0:f77369cabd75 101 * basically a copy of the entire IP/TCP header from the last packet
hattori_atsushi 0:f77369cabd75 102 * we saw from the conversation together with a small identifier
hattori_atsushi 0:f77369cabd75 103 * the transmit & receive ends of the line use to locate saved header.
hattori_atsushi 0:f77369cabd75 104 */
hattori_atsushi 0:f77369cabd75 105 struct cstate {
hattori_atsushi 0:f77369cabd75 106 struct cstate *cs_next; /* next most recently used state (xmit only) */
hattori_atsushi 0:f77369cabd75 107 u_short cs_hlen; /* size of hdr (receive only) */
hattori_atsushi 0:f77369cabd75 108 u_char cs_id; /* connection # associated with this state */
hattori_atsushi 0:f77369cabd75 109 u_char cs_filler;
hattori_atsushi 0:f77369cabd75 110 union {
hattori_atsushi 0:f77369cabd75 111 char csu_hdr[MAX_HDR];
hattori_atsushi 0:f77369cabd75 112 struct ip_hdr csu_ip; /* ip/tcp hdr from most recent packet */
hattori_atsushi 0:f77369cabd75 113 } vjcs_u;
hattori_atsushi 0:f77369cabd75 114 };
hattori_atsushi 0:f77369cabd75 115 #define cs_ip vjcs_u.csu_ip
hattori_atsushi 0:f77369cabd75 116 #define cs_hdr vjcs_u.csu_hdr
hattori_atsushi 0:f77369cabd75 117
hattori_atsushi 0:f77369cabd75 118
hattori_atsushi 0:f77369cabd75 119 struct vjstat {
hattori_atsushi 0:f77369cabd75 120 unsigned long vjs_packets; /* outbound packets */
hattori_atsushi 0:f77369cabd75 121 unsigned long vjs_compressed; /* outbound compressed packets */
hattori_atsushi 0:f77369cabd75 122 unsigned long vjs_searches; /* searches for connection state */
hattori_atsushi 0:f77369cabd75 123 unsigned long vjs_misses; /* times couldn't find conn. state */
hattori_atsushi 0:f77369cabd75 124 unsigned long vjs_uncompressedin; /* inbound uncompressed packets */
hattori_atsushi 0:f77369cabd75 125 unsigned long vjs_compressedin; /* inbound compressed packets */
hattori_atsushi 0:f77369cabd75 126 unsigned long vjs_errorin; /* inbound unknown type packets */
hattori_atsushi 0:f77369cabd75 127 unsigned long vjs_tossed; /* inbound packets tossed because of error */
hattori_atsushi 0:f77369cabd75 128 };
hattori_atsushi 0:f77369cabd75 129
hattori_atsushi 0:f77369cabd75 130 /*
hattori_atsushi 0:f77369cabd75 131 * all the state data for one serial line (we need one of these per line).
hattori_atsushi 0:f77369cabd75 132 */
hattori_atsushi 0:f77369cabd75 133 struct vjcompress {
hattori_atsushi 0:f77369cabd75 134 struct cstate *last_cs; /* most recently used tstate */
hattori_atsushi 0:f77369cabd75 135 u_char last_recv; /* last rcvd conn. id */
hattori_atsushi 0:f77369cabd75 136 u_char last_xmit; /* last sent conn. id */
hattori_atsushi 0:f77369cabd75 137 u_short flags;
hattori_atsushi 0:f77369cabd75 138 u_char maxSlotIndex;
hattori_atsushi 0:f77369cabd75 139 u_char compressSlot; /* Flag indicating OK to compress slot ID. */
hattori_atsushi 0:f77369cabd75 140 #if LINK_STATS
hattori_atsushi 0:f77369cabd75 141 struct vjstat stats;
hattori_atsushi 0:f77369cabd75 142 #endif
hattori_atsushi 0:f77369cabd75 143 struct cstate tstate[MAX_SLOTS]; /* xmit connection states */
hattori_atsushi 0:f77369cabd75 144 struct cstate rstate[MAX_SLOTS]; /* receive connection states */
hattori_atsushi 0:f77369cabd75 145 };
hattori_atsushi 0:f77369cabd75 146
hattori_atsushi 0:f77369cabd75 147 /* flag values */
hattori_atsushi 0:f77369cabd75 148 #define VJF_TOSS 1U /* tossing rcvd frames because of input err */
hattori_atsushi 0:f77369cabd75 149
hattori_atsushi 0:f77369cabd75 150 extern void vj_compress_init (struct vjcompress *comp);
hattori_atsushi 0:f77369cabd75 151 extern u_int vj_compress_tcp (struct vjcompress *comp, struct pbuf *pb);
hattori_atsushi 0:f77369cabd75 152 extern void vj_uncompress_err (struct vjcompress *comp);
hattori_atsushi 0:f77369cabd75 153 extern int vj_uncompress_uncomp(struct pbuf *nb, struct vjcompress *comp);
hattori_atsushi 0:f77369cabd75 154 extern int vj_uncompress_tcp (struct pbuf **nb, struct vjcompress *comp);
hattori_atsushi 0:f77369cabd75 155
hattori_atsushi 0:f77369cabd75 156 #endif /* VJ_H */