mirror of
https://github.com/johncobb/avr_328p_freertos.git
synced 2025-07-08 16:11:03 +03:00
added support for lwip
This commit is contained in:
John Cobb
155
lwip/netif/ppp/vj.h
Normal file
155
lwip/netif/ppp/vj.h
Normal file
@ -0,0 +1,155 @@
|
||||
/*
|
||||
* Definitions for tcp compression routines.
|
||||
*
|
||||
* $Id: vj.h,v 1.4 2004/02/07 00:30:03 likewise Exp $
|
||||
*
|
||||
* Copyright (c) 1989 Regents of the University of California.
|
||||
* All rights reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms are permitted
|
||||
* provided that the above copyright notice and this paragraph are
|
||||
* duplicated in all such forms and that any documentation,
|
||||
* advertising materials, and other materials related to such
|
||||
* distribution and use acknowledge that the software was developed
|
||||
* by the University of California, Berkeley. The name of the
|
||||
* University may not be used to endorse or promote products derived
|
||||
* from this software without specific prior written permission.
|
||||
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
|
||||
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
|
||||
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
||||
*
|
||||
* Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
|
||||
* - Initial distribution.
|
||||
*/
|
||||
|
||||
#ifndef VJ_H
|
||||
#define VJ_H
|
||||
|
||||
#include "vjbsdhdr.h"
|
||||
|
||||
#define MAX_SLOTS 16 /* must be > 2 and < 256 */
|
||||
#define MAX_HDR 128
|
||||
|
||||
/*
|
||||
* Compressed packet format:
|
||||
*
|
||||
* The first octet contains the packet type (top 3 bits), TCP
|
||||
* 'push' bit, and flags that indicate which of the 4 TCP sequence
|
||||
* numbers have changed (bottom 5 bits). The next octet is a
|
||||
* conversation number that associates a saved IP/TCP header with
|
||||
* the compressed packet. The next two octets are the TCP checksum
|
||||
* from the original datagram. The next 0 to 15 octets are
|
||||
* sequence number changes, one change per bit set in the header
|
||||
* (there may be no changes and there are two special cases where
|
||||
* the receiver implicitly knows what changed -- see below).
|
||||
*
|
||||
* There are 5 numbers which can change (they are always inserted
|
||||
* in the following order): TCP urgent pointer, window,
|
||||
* acknowlegement, sequence number and IP ID. (The urgent pointer
|
||||
* is different from the others in that its value is sent, not the
|
||||
* change in value.) Since typical use of SLIP links is biased
|
||||
* toward small packets (see comments on MTU/MSS below), changes
|
||||
* use a variable length coding with one octet for numbers in the
|
||||
* range 1 - 255 and 3 octets (0, MSB, LSB) for numbers in the
|
||||
* range 256 - 65535 or 0. (If the change in sequence number or
|
||||
* ack is more than 65535, an uncompressed packet is sent.)
|
||||
*/
|
||||
|
||||
/*
|
||||
* Packet types (must not conflict with IP protocol version)
|
||||
*
|
||||
* The top nibble of the first octet is the packet type. There are
|
||||
* three possible types: IP (not proto TCP or tcp with one of the
|
||||
* control flags set); uncompressed TCP (a normal IP/TCP packet but
|
||||
* with the 8-bit protocol field replaced by an 8-bit connection id --
|
||||
* this type of packet syncs the sender & receiver); and compressed
|
||||
* TCP (described above).
|
||||
*
|
||||
* LSB of 4-bit field is TCP "PUSH" bit (a worthless anachronism) and
|
||||
* is logically part of the 4-bit "changes" field that follows. Top
|
||||
* three bits are actual packet type. For backward compatibility
|
||||
* and in the interest of conserving bits, numbers are chosen so the
|
||||
* IP protocol version number (4) which normally appears in this nibble
|
||||
* means "IP packet".
|
||||
*/
|
||||
|
||||
/* packet types */
|
||||
#define TYPE_IP 0x40
|
||||
#define TYPE_UNCOMPRESSED_TCP 0x70
|
||||
#define TYPE_COMPRESSED_TCP 0x80
|
||||
#define TYPE_ERROR 0x00
|
||||
|
||||
/* Bits in first octet of compressed packet */
|
||||
#define NEW_C 0x40 /* flag bits for what changed in a packet */
|
||||
#define NEW_I 0x20
|
||||
#define NEW_S 0x08
|
||||
#define NEW_A 0x04
|
||||
#define NEW_W 0x02
|
||||
#define NEW_U 0x01
|
||||
|
||||
/* reserved, special-case values of above */
|
||||
#define SPECIAL_I (NEW_S|NEW_W|NEW_U) /* echoed interactive traffic */
|
||||
#define SPECIAL_D (NEW_S|NEW_A|NEW_W|NEW_U) /* unidirectional data */
|
||||
#define SPECIALS_MASK (NEW_S|NEW_A|NEW_W|NEW_U)
|
||||
|
||||
#define TCP_PUSH_BIT 0x10
|
||||
|
||||
|
||||
/*
|
||||
* "state" data for each active tcp conversation on the wire. This is
|
||||
* basically a copy of the entire IP/TCP header from the last packet
|
||||
* we saw from the conversation together with a small identifier
|
||||
* the transmit & receive ends of the line use to locate saved header.
|
||||
*/
|
||||
struct cstate {
|
||||
struct cstate *cs_next; /* next most recently used state (xmit only) */
|
||||
u_short cs_hlen; /* size of hdr (receive only) */
|
||||
u_char cs_id; /* connection # associated with this state */
|
||||
u_char cs_filler;
|
||||
union {
|
||||
char csu_hdr[MAX_HDR];
|
||||
struct ip csu_ip; /* ip/tcp hdr from most recent packet */
|
||||
} vjcs_u;
|
||||
};
|
||||
#define cs_ip vjcs_u.csu_ip
|
||||
#define cs_hdr vjcs_u.csu_hdr
|
||||
|
||||
|
||||
struct vjstat {
|
||||
unsigned long vjs_packets; /* outbound packets */
|
||||
unsigned long vjs_compressed; /* outbound compressed packets */
|
||||
unsigned long vjs_searches; /* searches for connection state */
|
||||
unsigned long vjs_misses; /* times couldn't find conn. state */
|
||||
unsigned long vjs_uncompressedin; /* inbound uncompressed packets */
|
||||
unsigned long vjs_compressedin; /* inbound compressed packets */
|
||||
unsigned long vjs_errorin; /* inbound unknown type packets */
|
||||
unsigned long vjs_tossed; /* inbound packets tossed because of error */
|
||||
};
|
||||
|
||||
/*
|
||||
* all the state data for one serial line (we need one of these per line).
|
||||
*/
|
||||
struct vjcompress {
|
||||
struct cstate *last_cs; /* most recently used tstate */
|
||||
u_char last_recv; /* last rcvd conn. id */
|
||||
u_char last_xmit; /* last sent conn. id */
|
||||
u_short flags;
|
||||
u_char maxSlotIndex;
|
||||
u_char compressSlot; /* Flag indicating OK to compress slot ID. */
|
||||
#if LINK_STATS
|
||||
struct vjstat stats;
|
||||
#endif
|
||||
struct cstate tstate[MAX_SLOTS]; /* xmit connection states */
|
||||
struct cstate rstate[MAX_SLOTS]; /* receive connection states */
|
||||
};
|
||||
|
||||
/* flag values */
|
||||
#define VJF_TOSS 1U /* tossing rcvd frames because of input err */
|
||||
|
||||
extern void vj_compress_init (struct vjcompress *comp);
|
||||
extern u_int vj_compress_tcp (struct vjcompress *comp, struct pbuf *pb);
|
||||
extern void vj_uncompress_err (struct vjcompress *comp);
|
||||
extern int vj_uncompress_uncomp(struct pbuf *nb, struct vjcompress *comp);
|
||||
extern int vj_uncompress_tcp(struct pbuf **nb, struct vjcompress *comp);
|
||||
|
||||
#endif /* VJ_H */
|
||||
Reference in New Issue
Block a user