Sam Walsh / F7_Ethernet_F746ZG

Forked from the DieterGraef Library

Fork of F7_Ethernet by Dieter Graef

lwip/netif/ppp/vj.h@2:fdef48f830c0, 2016-11-18 (annotated)

Committer:
EmbeddedSam
Date:
Fri Nov 18 12:48:10 2016 +0000
Revision:
2:fdef48f830c0
Parent:
0:d26c1b55cfca 
Linking MQTT together, starting with mbed-cli

Who changed what in which revision?

UserRevisionLine numberNew contents of line
DieterGraef 0:d26c1b55cfca 1 /*
DieterGraef 0:d26c1b55cfca 2 * Definitions for tcp compression routines.
DieterGraef 0:d26c1b55cfca 3 *
DieterGraef 0:d26c1b55cfca 4 * $Id: vj.h,v 1.7 2010/02/22 17:52:09 goldsimon Exp $
DieterGraef 0:d26c1b55cfca 5 *
DieterGraef 0:d26c1b55cfca 6 * Copyright (c) 1989 Regents of the University of California.
DieterGraef 0:d26c1b55cfca 7 * All rights reserved.
DieterGraef 0:d26c1b55cfca 8 *
DieterGraef 0:d26c1b55cfca 9 * Redistribution and use in source and binary forms are permitted
DieterGraef 0:d26c1b55cfca 10 * provided that the above copyright notice and this paragraph are
DieterGraef 0:d26c1b55cfca 11 * duplicated in all such forms and that any documentation,
DieterGraef 0:d26c1b55cfca 12 * advertising materials, and other materials related to such
DieterGraef 0:d26c1b55cfca 13 * distribution and use acknowledge that the software was developed
DieterGraef 0:d26c1b55cfca 14 * by the University of California, Berkeley. The name of the
DieterGraef 0:d26c1b55cfca 15 * University may not be used to endorse or promote products derived
DieterGraef 0:d26c1b55cfca 16 * from this software without specific prior written permission.
DieterGraef 0:d26c1b55cfca 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
DieterGraef 0:d26c1b55cfca 18 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
DieterGraef 0:d26c1b55cfca 19 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
DieterGraef 0:d26c1b55cfca 20 *
DieterGraef 0:d26c1b55cfca 21 * Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
DieterGraef 0:d26c1b55cfca 22 * - Initial distribution.
DieterGraef 0:d26c1b55cfca 23 */
DieterGraef 0:d26c1b55cfca 24
DieterGraef 0:d26c1b55cfca 25 #ifndef VJ_H
DieterGraef 0:d26c1b55cfca 26 #define VJ_H
DieterGraef 0:d26c1b55cfca 27
DieterGraef 0:d26c1b55cfca 28 #include "lwip/ip.h"
DieterGraef 0:d26c1b55cfca 29 #include "lwip/tcp_impl.h"
DieterGraef 0:d26c1b55cfca 30
DieterGraef 0:d26c1b55cfca 31 #define MAX_SLOTS 16 /* must be > 2 and < 256 */
DieterGraef 0:d26c1b55cfca 32 #define MAX_HDR 128
DieterGraef 0:d26c1b55cfca 33
DieterGraef 0:d26c1b55cfca 34 /*
DieterGraef 0:d26c1b55cfca 35 * Compressed packet format:
DieterGraef 0:d26c1b55cfca 36 *
DieterGraef 0:d26c1b55cfca 37 * The first octet contains the packet type (top 3 bits), TCP
DieterGraef 0:d26c1b55cfca 38 * 'push' bit, and flags that indicate which of the 4 TCP sequence
DieterGraef 0:d26c1b55cfca 39 * numbers have changed (bottom 5 bits). The next octet is a
DieterGraef 0:d26c1b55cfca 40 * conversation number that associates a saved IP/TCP header with
DieterGraef 0:d26c1b55cfca 41 * the compressed packet. The next two octets are the TCP checksum
DieterGraef 0:d26c1b55cfca 42 * from the original datagram. The next 0 to 15 octets are
DieterGraef 0:d26c1b55cfca 43 * sequence number changes, one change per bit set in the header
DieterGraef 0:d26c1b55cfca 44 * (there may be no changes and there are two special cases where
DieterGraef 0:d26c1b55cfca 45 * the receiver implicitly knows what changed -- see below).
DieterGraef 0:d26c1b55cfca 46 *
DieterGraef 0:d26c1b55cfca 47 * There are 5 numbers which can change (they are always inserted
DieterGraef 0:d26c1b55cfca 48 * in the following order): TCP urgent pointer, window,
DieterGraef 0:d26c1b55cfca 49 * acknowlegement, sequence number and IP ID. (The urgent pointer
DieterGraef 0:d26c1b55cfca 50 * is different from the others in that its value is sent, not the
DieterGraef 0:d26c1b55cfca 51 * change in value.) Since typical use of SLIP links is biased
DieterGraef 0:d26c1b55cfca 52 * toward small packets (see comments on MTU/MSS below), changes
DieterGraef 0:d26c1b55cfca 53 * use a variable length coding with one octet for numbers in the
DieterGraef 0:d26c1b55cfca 54 * range 1 - 255 and 3 octets (0, MSB, LSB) for numbers in the
DieterGraef 0:d26c1b55cfca 55 * range 256 - 65535 or 0. (If the change in sequence number or
DieterGraef 0:d26c1b55cfca 56 * ack is more than 65535, an uncompressed packet is sent.)
DieterGraef 0:d26c1b55cfca 57 */
DieterGraef 0:d26c1b55cfca 58
DieterGraef 0:d26c1b55cfca 59 /*
DieterGraef 0:d26c1b55cfca 60 * Packet types (must not conflict with IP protocol version)
DieterGraef 0:d26c1b55cfca 61 *
DieterGraef 0:d26c1b55cfca 62 * The top nibble of the first octet is the packet type. There are
DieterGraef 0:d26c1b55cfca 63 * three possible types: IP (not proto TCP or tcp with one of the
DieterGraef 0:d26c1b55cfca 64 * control flags set); uncompressed TCP (a normal IP/TCP packet but
DieterGraef 0:d26c1b55cfca 65 * with the 8-bit protocol field replaced by an 8-bit connection id --
DieterGraef 0:d26c1b55cfca 66 * this type of packet syncs the sender & receiver); and compressed
DieterGraef 0:d26c1b55cfca 67 * TCP (described above).
DieterGraef 0:d26c1b55cfca 68 *
DieterGraef 0:d26c1b55cfca 69 * LSB of 4-bit field is TCP "PUSH" bit (a worthless anachronism) and
DieterGraef 0:d26c1b55cfca 70 * is logically part of the 4-bit "changes" field that follows. Top
DieterGraef 0:d26c1b55cfca 71 * three bits are actual packet type. For backward compatibility
DieterGraef 0:d26c1b55cfca 72 * and in the interest of conserving bits, numbers are chosen so the
DieterGraef 0:d26c1b55cfca 73 * IP protocol version number (4) which normally appears in this nibble
DieterGraef 0:d26c1b55cfca 74 * means "IP packet".
DieterGraef 0:d26c1b55cfca 75 */
DieterGraef 0:d26c1b55cfca 76
DieterGraef 0:d26c1b55cfca 77 /* packet types */
DieterGraef 0:d26c1b55cfca 78 #define TYPE_IP 0x40
DieterGraef 0:d26c1b55cfca 79 #define TYPE_UNCOMPRESSED_TCP 0x70
DieterGraef 0:d26c1b55cfca 80 #define TYPE_COMPRESSED_TCP 0x80
DieterGraef 0:d26c1b55cfca 81 #define TYPE_ERROR 0x00
DieterGraef 0:d26c1b55cfca 82
DieterGraef 0:d26c1b55cfca 83 /* Bits in first octet of compressed packet */
DieterGraef 0:d26c1b55cfca 84 #define NEW_C 0x40 /* flag bits for what changed in a packet */
DieterGraef 0:d26c1b55cfca 85 #define NEW_I 0x20
DieterGraef 0:d26c1b55cfca 86 #define NEW_S 0x08
DieterGraef 0:d26c1b55cfca 87 #define NEW_A 0x04
DieterGraef 0:d26c1b55cfca 88 #define NEW_W 0x02
DieterGraef 0:d26c1b55cfca 89 #define NEW_U 0x01
DieterGraef 0:d26c1b55cfca 90
DieterGraef 0:d26c1b55cfca 91 /* reserved, special-case values of above */
DieterGraef 0:d26c1b55cfca 92 #define SPECIAL_I (NEW_S|NEW_W|NEW_U) /* echoed interactive traffic */
DieterGraef 0:d26c1b55cfca 93 #define SPECIAL_D (NEW_S|NEW_A|NEW_W|NEW_U) /* unidirectional data */
DieterGraef 0:d26c1b55cfca 94 #define SPECIALS_MASK (NEW_S|NEW_A|NEW_W|NEW_U)
DieterGraef 0:d26c1b55cfca 95
DieterGraef 0:d26c1b55cfca 96 #define TCP_PUSH_BIT 0x10
DieterGraef 0:d26c1b55cfca 97
DieterGraef 0:d26c1b55cfca 98
DieterGraef 0:d26c1b55cfca 99 /*
DieterGraef 0:d26c1b55cfca 100 * "state" data for each active tcp conversation on the wire. This is
DieterGraef 0:d26c1b55cfca 101 * basically a copy of the entire IP/TCP header from the last packet
DieterGraef 0:d26c1b55cfca 102 * we saw from the conversation together with a small identifier
DieterGraef 0:d26c1b55cfca 103 * the transmit & receive ends of the line use to locate saved header.
DieterGraef 0:d26c1b55cfca 104 */
DieterGraef 0:d26c1b55cfca 105 struct cstate {
DieterGraef 0:d26c1b55cfca 106 struct cstate *cs_next; /* next most recently used state (xmit only) */
DieterGraef 0:d26c1b55cfca 107 u_short cs_hlen; /* size of hdr (receive only) */
DieterGraef 0:d26c1b55cfca 108 u_char cs_id; /* connection # associated with this state */
DieterGraef 0:d26c1b55cfca 109 u_char cs_filler;
DieterGraef 0:d26c1b55cfca 110 union {
DieterGraef 0:d26c1b55cfca 111 char csu_hdr[MAX_HDR];
DieterGraef 0:d26c1b55cfca 112 struct ip_hdr csu_ip; /* ip/tcp hdr from most recent packet */
DieterGraef 0:d26c1b55cfca 113 } vjcs_u;
DieterGraef 0:d26c1b55cfca 114 };
DieterGraef 0:d26c1b55cfca 115 #define cs_ip vjcs_u.csu_ip
DieterGraef 0:d26c1b55cfca 116 #define cs_hdr vjcs_u.csu_hdr
DieterGraef 0:d26c1b55cfca 117
DieterGraef 0:d26c1b55cfca 118
DieterGraef 0:d26c1b55cfca 119 struct vjstat {
DieterGraef 0:d26c1b55cfca 120 unsigned long vjs_packets; /* outbound packets */
DieterGraef 0:d26c1b55cfca 121 unsigned long vjs_compressed; /* outbound compressed packets */
DieterGraef 0:d26c1b55cfca 122 unsigned long vjs_searches; /* searches for connection state */
DieterGraef 0:d26c1b55cfca 123 unsigned long vjs_misses; /* times couldn't find conn. state */
DieterGraef 0:d26c1b55cfca 124 unsigned long vjs_uncompressedin; /* inbound uncompressed packets */
DieterGraef 0:d26c1b55cfca 125 unsigned long vjs_compressedin; /* inbound compressed packets */
DieterGraef 0:d26c1b55cfca 126 unsigned long vjs_errorin; /* inbound unknown type packets */
DieterGraef 0:d26c1b55cfca 127 unsigned long vjs_tossed; /* inbound packets tossed because of error */
DieterGraef 0:d26c1b55cfca 128 };
DieterGraef 0:d26c1b55cfca 129
DieterGraef 0:d26c1b55cfca 130 /*
DieterGraef 0:d26c1b55cfca 131 * all the state data for one serial line (we need one of these per line).
DieterGraef 0:d26c1b55cfca 132 */
DieterGraef 0:d26c1b55cfca 133 struct vjcompress {
DieterGraef 0:d26c1b55cfca 134 struct cstate *last_cs; /* most recently used tstate */
DieterGraef 0:d26c1b55cfca 135 u_char last_recv; /* last rcvd conn. id */
DieterGraef 0:d26c1b55cfca 136 u_char last_xmit; /* last sent conn. id */
DieterGraef 0:d26c1b55cfca 137 u_short flags;
DieterGraef 0:d26c1b55cfca 138 u_char maxSlotIndex;
DieterGraef 0:d26c1b55cfca 139 u_char compressSlot; /* Flag indicating OK to compress slot ID. */
DieterGraef 0:d26c1b55cfca 140 #if LINK_STATS
DieterGraef 0:d26c1b55cfca 141 struct vjstat stats;
DieterGraef 0:d26c1b55cfca 142 #endif
DieterGraef 0:d26c1b55cfca 143 struct cstate tstate[MAX_SLOTS]; /* xmit connection states */
DieterGraef 0:d26c1b55cfca 144 struct cstate rstate[MAX_SLOTS]; /* receive connection states */
DieterGraef 0:d26c1b55cfca 145 };
DieterGraef 0:d26c1b55cfca 146
DieterGraef 0:d26c1b55cfca 147 /* flag values */
DieterGraef 0:d26c1b55cfca 148 #define VJF_TOSS 1U /* tossing rcvd frames because of input err */
DieterGraef 0:d26c1b55cfca 149
DieterGraef 0:d26c1b55cfca 150 extern void vj_compress_init (struct vjcompress *comp);
DieterGraef 0:d26c1b55cfca 151 extern u_int vj_compress_tcp (struct vjcompress *comp, struct pbuf *pb);
DieterGraef 0:d26c1b55cfca 152 extern void vj_uncompress_err (struct vjcompress *comp);
DieterGraef 0:d26c1b55cfca 153 extern int vj_uncompress_uncomp(struct pbuf *nb, struct vjcompress *comp);
DieterGraef 0:d26c1b55cfca 154 extern int vj_uncompress_tcp (struct pbuf **nb, struct vjcompress *comp);
DieterGraef 0:d26c1b55cfca 155
DieterGraef 0:d26c1b55cfca 156 #endif /* VJ_H */