Rod Coleman / NetServices

Netservices modded to read fragmented HTTP respsonse/payload from special purpose server - 180 bytes only

lwip/netif/ppp/vj.h@0:8f5825f330b0, 2011-09-08 (annotated)

Committer:
RodColeman
Date:
Thu Sep 08 10:41:36 2011 +0000
Revision:
0:8f5825f330b0
setDataLen hacked to 180bytes

Who changed what in which revision?

UserRevisionLine numberNew contents of line
RodColeman 0:8f5825f330b0 1 /*
RodColeman 0:8f5825f330b0 2 * Definitions for tcp compression routines.
RodColeman 0:8f5825f330b0 3 *
RodColeman 0:8f5825f330b0 4 * $Id: vj.h,v 1.7 2010/02/22 17:52:09 goldsimon Exp $
RodColeman 0:8f5825f330b0 5 *
RodColeman 0:8f5825f330b0 6 * Copyright (c) 1989 Regents of the University of California.
RodColeman 0:8f5825f330b0 7 * All rights reserved.
RodColeman 0:8f5825f330b0 8 *
RodColeman 0:8f5825f330b0 9 * Redistribution and use in source and binary forms are permitted
RodColeman 0:8f5825f330b0 10 * provided that the above copyright notice and this paragraph are
RodColeman 0:8f5825f330b0 11 * duplicated in all such forms and that any documentation,
RodColeman 0:8f5825f330b0 12 * advertising materials, and other materials related to such
RodColeman 0:8f5825f330b0 13 * distribution and use acknowledge that the software was developed
RodColeman 0:8f5825f330b0 14 * by the University of California, Berkeley. The name of the
RodColeman 0:8f5825f330b0 15 * University may not be used to endorse or promote products derived
RodColeman 0:8f5825f330b0 16 * from this software without specific prior written permission.
RodColeman 0:8f5825f330b0 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
RodColeman 0:8f5825f330b0 18 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
RodColeman 0:8f5825f330b0 19 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
RodColeman 0:8f5825f330b0 20 *
RodColeman 0:8f5825f330b0 21 * Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
RodColeman 0:8f5825f330b0 22 * - Initial distribution.
RodColeman 0:8f5825f330b0 23 */
RodColeman 0:8f5825f330b0 24
RodColeman 0:8f5825f330b0 25 #ifndef VJ_H
RodColeman 0:8f5825f330b0 26 #define VJ_H
RodColeman 0:8f5825f330b0 27
RodColeman 0:8f5825f330b0 28 #include "lwip/ip.h"
RodColeman 0:8f5825f330b0 29 #include "lwip/tcp_impl.h"
RodColeman 0:8f5825f330b0 30
RodColeman 0:8f5825f330b0 31 #define MAX_SLOTS 16 /* must be > 2 and < 256 */
RodColeman 0:8f5825f330b0 32 #define MAX_HDR 128
RodColeman 0:8f5825f330b0 33
RodColeman 0:8f5825f330b0 34 /*
RodColeman 0:8f5825f330b0 35 * Compressed packet format:
RodColeman 0:8f5825f330b0 36 *
RodColeman 0:8f5825f330b0 37 * The first octet contains the packet type (top 3 bits), TCP
RodColeman 0:8f5825f330b0 38 * 'push' bit, and flags that indicate which of the 4 TCP sequence
RodColeman 0:8f5825f330b0 39 * numbers have changed (bottom 5 bits). The next octet is a
RodColeman 0:8f5825f330b0 40 * conversation number that associates a saved IP/TCP header with
RodColeman 0:8f5825f330b0 41 * the compressed packet. The next two octets are the TCP checksum
RodColeman 0:8f5825f330b0 42 * from the original datagram. The next 0 to 15 octets are
RodColeman 0:8f5825f330b0 43 * sequence number changes, one change per bit set in the header
RodColeman 0:8f5825f330b0 44 * (there may be no changes and there are two special cases where
RodColeman 0:8f5825f330b0 45 * the receiver implicitly knows what changed -- see below).
RodColeman 0:8f5825f330b0 46 *
RodColeman 0:8f5825f330b0 47 * There are 5 numbers which can change (they are always inserted
RodColeman 0:8f5825f330b0 48 * in the following order): TCP urgent pointer, window,
RodColeman 0:8f5825f330b0 49 * acknowlegement, sequence number and IP ID. (The urgent pointer
RodColeman 0:8f5825f330b0 50 * is different from the others in that its value is sent, not the
RodColeman 0:8f5825f330b0 51 * change in value.) Since typical use of SLIP links is biased
RodColeman 0:8f5825f330b0 52 * toward small packets (see comments on MTU/MSS below), changes
RodColeman 0:8f5825f330b0 53 * use a variable length coding with one octet for numbers in the
RodColeman 0:8f5825f330b0 54 * range 1 - 255 and 3 octets (0, MSB, LSB) for numbers in the
RodColeman 0:8f5825f330b0 55 * range 256 - 65535 or 0. (If the change in sequence number or
RodColeman 0:8f5825f330b0 56 * ack is more than 65535, an uncompressed packet is sent.)
RodColeman 0:8f5825f330b0 57 */
RodColeman 0:8f5825f330b0 58
RodColeman 0:8f5825f330b0 59 /*
RodColeman 0:8f5825f330b0 60 * Packet types (must not conflict with IP protocol version)
RodColeman 0:8f5825f330b0 61 *
RodColeman 0:8f5825f330b0 62 * The top nibble of the first octet is the packet type. There are
RodColeman 0:8f5825f330b0 63 * three possible types: IP (not proto TCP or tcp with one of the
RodColeman 0:8f5825f330b0 64 * control flags set); uncompressed TCP (a normal IP/TCP packet but
RodColeman 0:8f5825f330b0 65 * with the 8-bit protocol field replaced by an 8-bit connection id --
RodColeman 0:8f5825f330b0 66 * this type of packet syncs the sender & receiver); and compressed
RodColeman 0:8f5825f330b0 67 * TCP (described above).
RodColeman 0:8f5825f330b0 68 *
RodColeman 0:8f5825f330b0 69 * LSB of 4-bit field is TCP "PUSH" bit (a worthless anachronism) and
RodColeman 0:8f5825f330b0 70 * is logically part of the 4-bit "changes" field that follows. Top
RodColeman 0:8f5825f330b0 71 * three bits are actual packet type. For backward compatibility
RodColeman 0:8f5825f330b0 72 * and in the interest of conserving bits, numbers are chosen so the
RodColeman 0:8f5825f330b0 73 * IP protocol version number (4) which normally appears in this nibble
RodColeman 0:8f5825f330b0 74 * means "IP packet".
RodColeman 0:8f5825f330b0 75 */
RodColeman 0:8f5825f330b0 76
RodColeman 0:8f5825f330b0 77 /* packet types */
RodColeman 0:8f5825f330b0 78 #define TYPE_IP 0x40
RodColeman 0:8f5825f330b0 79 #define TYPE_UNCOMPRESSED_TCP 0x70
RodColeman 0:8f5825f330b0 80 #define TYPE_COMPRESSED_TCP 0x80
RodColeman 0:8f5825f330b0 81 #define TYPE_ERROR 0x00
RodColeman 0:8f5825f330b0 82
RodColeman 0:8f5825f330b0 83 /* Bits in first octet of compressed packet */
RodColeman 0:8f5825f330b0 84 #define NEW_C 0x40 /* flag bits for what changed in a packet */
RodColeman 0:8f5825f330b0 85 #define NEW_I 0x20
RodColeman 0:8f5825f330b0 86 #define NEW_S 0x08
RodColeman 0:8f5825f330b0 87 #define NEW_A 0x04
RodColeman 0:8f5825f330b0 88 #define NEW_W 0x02
RodColeman 0:8f5825f330b0 89 #define NEW_U 0x01
RodColeman 0:8f5825f330b0 90
RodColeman 0:8f5825f330b0 91 /* reserved, special-case values of above */
RodColeman 0:8f5825f330b0 92 #define SPECIAL_I (NEW_S|NEW_W|NEW_U) /* echoed interactive traffic */
RodColeman 0:8f5825f330b0 93 #define SPECIAL_D (NEW_S|NEW_A|NEW_W|NEW_U) /* unidirectional data */
RodColeman 0:8f5825f330b0 94 #define SPECIALS_MASK (NEW_S|NEW_A|NEW_W|NEW_U)
RodColeman 0:8f5825f330b0 95
RodColeman 0:8f5825f330b0 96 #define TCP_PUSH_BIT 0x10
RodColeman 0:8f5825f330b0 97
RodColeman 0:8f5825f330b0 98
RodColeman 0:8f5825f330b0 99 /*
RodColeman 0:8f5825f330b0 100 * "state" data for each active tcp conversation on the wire. This is
RodColeman 0:8f5825f330b0 101 * basically a copy of the entire IP/TCP header from the last packet
RodColeman 0:8f5825f330b0 102 * we saw from the conversation together with a small identifier
RodColeman 0:8f5825f330b0 103 * the transmit & receive ends of the line use to locate saved header.
RodColeman 0:8f5825f330b0 104 */
RodColeman 0:8f5825f330b0 105 struct cstate {
RodColeman 0:8f5825f330b0 106 struct cstate *cs_next; /* next most recently used state (xmit only) */
RodColeman 0:8f5825f330b0 107 u_short cs_hlen; /* size of hdr (receive only) */
RodColeman 0:8f5825f330b0 108 u_char cs_id; /* connection # associated with this state */
RodColeman 0:8f5825f330b0 109 u_char cs_filler;
RodColeman 0:8f5825f330b0 110 union {
RodColeman 0:8f5825f330b0 111 char csu_hdr[MAX_HDR];
RodColeman 0:8f5825f330b0 112 struct ip_hdr csu_ip; /* ip/tcp hdr from most recent packet */
RodColeman 0:8f5825f330b0 113 } vjcs_u;
RodColeman 0:8f5825f330b0 114 };
RodColeman 0:8f5825f330b0 115 #define cs_ip vjcs_u.csu_ip
RodColeman 0:8f5825f330b0 116 #define cs_hdr vjcs_u.csu_hdr
RodColeman 0:8f5825f330b0 117
RodColeman 0:8f5825f330b0 118
RodColeman 0:8f5825f330b0 119 struct vjstat {
RodColeman 0:8f5825f330b0 120 unsigned long vjs_packets; /* outbound packets */
RodColeman 0:8f5825f330b0 121 unsigned long vjs_compressed; /* outbound compressed packets */
RodColeman 0:8f5825f330b0 122 unsigned long vjs_searches; /* searches for connection state */
RodColeman 0:8f5825f330b0 123 unsigned long vjs_misses; /* times couldn't find conn. state */
RodColeman 0:8f5825f330b0 124 unsigned long vjs_uncompressedin; /* inbound uncompressed packets */
RodColeman 0:8f5825f330b0 125 unsigned long vjs_compressedin; /* inbound compressed packets */
RodColeman 0:8f5825f330b0 126 unsigned long vjs_errorin; /* inbound unknown type packets */
RodColeman 0:8f5825f330b0 127 unsigned long vjs_tossed; /* inbound packets tossed because of error */
RodColeman 0:8f5825f330b0 128 };
RodColeman 0:8f5825f330b0 129
RodColeman 0:8f5825f330b0 130 /*
RodColeman 0:8f5825f330b0 131 * all the state data for one serial line (we need one of these per line).
RodColeman 0:8f5825f330b0 132 */
RodColeman 0:8f5825f330b0 133 struct vjcompress {
RodColeman 0:8f5825f330b0 134 struct cstate *last_cs; /* most recently used tstate */
RodColeman 0:8f5825f330b0 135 u_char last_recv; /* last rcvd conn. id */
RodColeman 0:8f5825f330b0 136 u_char last_xmit; /* last sent conn. id */
RodColeman 0:8f5825f330b0 137 u_short flags;
RodColeman 0:8f5825f330b0 138 u_char maxSlotIndex;
RodColeman 0:8f5825f330b0 139 u_char compressSlot; /* Flag indicating OK to compress slot ID. */
RodColeman 0:8f5825f330b0 140 #if LINK_STATS
RodColeman 0:8f5825f330b0 141 struct vjstat stats;
RodColeman 0:8f5825f330b0 142 #endif
RodColeman 0:8f5825f330b0 143 struct cstate tstate[MAX_SLOTS]; /* xmit connection states */
RodColeman 0:8f5825f330b0 144 struct cstate rstate[MAX_SLOTS]; /* receive connection states */
RodColeman 0:8f5825f330b0 145 };
RodColeman 0:8f5825f330b0 146
RodColeman 0:8f5825f330b0 147 /* flag values */
RodColeman 0:8f5825f330b0 148 #define VJF_TOSS 1U /* tossing rcvd frames because of input err */
RodColeman 0:8f5825f330b0 149
RodColeman 0:8f5825f330b0 150 extern void vj_compress_init (struct vjcompress *comp);
RodColeman 0:8f5825f330b0 151 extern u_int vj_compress_tcp (struct vjcompress *comp, struct pbuf *pb);
RodColeman 0:8f5825f330b0 152 extern void vj_uncompress_err (struct vjcompress *comp);
RodColeman 0:8f5825f330b0 153 extern int vj_uncompress_uncomp(struct pbuf *nb, struct vjcompress *comp);
RodColeman 0:8f5825f330b0 154 extern int vj_uncompress_tcp (struct pbuf **nb, struct vjcompress *comp);
RodColeman 0:8f5825f330b0 155
RodColeman 0:8f5825f330b0 156 #endif /* VJ_H */