Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) #ifndef _SLHC_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) #define _SLHC_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  * Definitions for tcp compression routines.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  * $Header: slcompress.h,v 1.10 89/12/31 08:53:02 van Exp $
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  * Copyright (c) 1989 Regents of the University of California.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9)  * All rights reserved.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11)  * Redistribution and use in source and binary forms are permitted
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12)  * provided that the above copyright notice and this paragraph are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13)  * duplicated in all such forms and that any documentation,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14)  * advertising materials, and other materials related to such
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15)  * distribution and use acknowledge that the software was developed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16)  * by the University of California, Berkeley.  The name of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17)  * University may not be used to endorse or promote products derived
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18)  * from this software without specific prior written permission.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19)  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20)  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21)  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23)  *	Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24)  *	- Initial distribution.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27)  * modified for KA9Q Internet Software Package by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28)  * Katie Stevens (dkstevens@ucdavis.edu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29)  * University of California, Davis
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30)  * Computing Services
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31)  *	- 01-31-90	initial adaptation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33)  *	- Feb 1991	Bill_Simpson@um.cc.umich.edu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34)  *			variable number of conversation slots
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35)  *			allow zero or one slots
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36)  *			separate routines
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37)  *			status display
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41)  * Compressed packet format:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43)  * The first octet contains the packet type (top 3 bits), TCP
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44)  * 'push' bit, and flags that indicate which of the 4 TCP sequence
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45)  * numbers have changed (bottom 5 bits).  The next octet is a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46)  * conversation number that associates a saved IP/TCP header with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47)  * the compressed packet.  The next two octets are the TCP checksum
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48)  * from the original datagram.  The next 0 to 15 octets are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49)  * sequence number changes, one change per bit set in the header
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50)  * (there may be no changes and there are two special cases where
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51)  * the receiver implicitly knows what changed -- see below).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53)  * There are 5 numbers which can change (they are always inserted
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54)  * in the following order): TCP urgent pointer, window,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55)  * acknowledgment, sequence number and IP ID.  (The urgent pointer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56)  * is different from the others in that its value is sent, not the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57)  * change in value.)  Since typical use of SLIP links is biased
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58)  * toward small packets (see comments on MTU/MSS below), changes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59)  * use a variable length coding with one octet for numbers in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60)  * range 1 - 255 and 3 octets (0, MSB, LSB) for numbers in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61)  * range 256 - 65535 or 0.  (If the change in sequence number or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62)  * ack is more than 65535, an uncompressed packet is sent.)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66)  * Packet types (must not conflict with IP protocol version)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68)  * The top nibble of the first octet is the packet type.  There are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69)  * three possible types: IP (not proto TCP or tcp with one of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70)  * control flags set); uncompressed TCP (a normal IP/TCP packet but
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71)  * with the 8-bit protocol field replaced by an 8-bit connection id --
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72)  * this type of packet syncs the sender & receiver); and compressed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73)  * TCP (described above).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75)  * LSB of 4-bit field is TCP "PUSH" bit (a worthless anachronism) and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76)  * is logically part of the 4-bit "changes" field that follows.  Top
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77)  * three bits are actual packet type.  For backward compatibility
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78)  * and in the interest of conserving bits, numbers are chosen so the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79)  * IP protocol version number (4) which normally appears in this nibble
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80)  * means "IP packet".
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) #include <linux/ip.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) #include <linux/tcp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) /* SLIP compression masks for len/vers byte */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) #define SL_TYPE_IP 0x40
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) #define SL_TYPE_UNCOMPRESSED_TCP 0x70
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) #define SL_TYPE_COMPRESSED_TCP 0x80
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) #define SL_TYPE_ERROR 0x00
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) /* Bits in first octet of compressed packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) #define NEW_C	0x40	/* flag bits for what changed in a packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) #define NEW_I	0x20
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) #define NEW_S	0x08
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) #define NEW_A	0x04
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) #define NEW_W	0x02
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) #define NEW_U	0x01
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) /* reserved, special-case values of above */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) #define SPECIAL_I (NEW_S|NEW_W|NEW_U)		/* echoed interactive traffic */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) #define SPECIAL_D (NEW_S|NEW_A|NEW_W|NEW_U)	/* unidirectional data */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) #define SPECIALS_MASK (NEW_S|NEW_A|NEW_W|NEW_U)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) #define TCP_PUSH_BIT 0x10
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109)  * data type and sizes conversion assumptions:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111)  *	VJ code		KA9Q style	generic
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)  *	u_char		byte_t		unsigned char	 8 bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113)  *	u_short		int16		unsigned short	16 bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114)  *	u_int		int16		unsigned short	16 bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)  *	u_long		unsigned long	unsigned long	32 bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)  *	int		int32		long		32 bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) typedef __u8 byte_t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) typedef __u32 int32;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)  * "state" data for each active tcp conversation on the wire.  This is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124)  * basically a copy of the entire IP/TCP header from the last packet
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125)  * we saw from the conversation together with a small identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)  * the transmit & receive ends of the line use to locate saved header.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) struct cstate {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	byte_t	cs_this;	/* connection id number (xmit) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 	bool	initialized;	/* true if initialized */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	struct cstate *next;	/* next in ring (xmit) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	struct iphdr cs_ip;	/* ip/tcp hdr from most recent packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	struct tcphdr cs_tcp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	unsigned char cs_ipopt[64];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	unsigned char cs_tcpopt[64];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	int cs_hsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) #define NULLSLSTATE	(struct cstate *)0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141)  * all the state data for one serial line (we need one of these per line).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) struct slcompress {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 	struct cstate *tstate;	/* transmit connection states (array)*/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	struct cstate *rstate;	/* receive connection states (array)*/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 	byte_t tslot_limit;	/* highest transmit slot id (0-l)*/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	byte_t rslot_limit;	/* highest receive slot id (0-l)*/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 	byte_t xmit_oldest;	/* oldest xmit in ring */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	byte_t xmit_current;	/* most recent xmit id */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	byte_t recv_current;	/* most recent rcvd id */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	byte_t flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) #define SLF_TOSS	0x01	/* tossing rcvd frames until id received */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	int32 sls_o_nontcp;	/* outbound non-TCP packets */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	int32 sls_o_tcp;	/* outbound TCP packets */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 	int32 sls_o_uncompressed;	/* outbound uncompressed packets */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	int32 sls_o_compressed;	/* outbound compressed packets */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	int32 sls_o_searches;	/* searches for connection state */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	int32 sls_o_misses;	/* times couldn't find conn. state */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	int32 sls_i_uncompressed;	/* inbound uncompressed packets */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	int32 sls_i_compressed;	/* inbound compressed packets */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	int32 sls_i_error;	/* inbound error packets */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	int32 sls_i_tossed;	/* inbound packets tossed because of error */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 	int32 sls_i_runt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 	int32 sls_i_badcheck;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) #define NULLSLCOMPR	(struct slcompress *)0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) /* In slhc.c: */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) struct slcompress *slhc_init(int rslots, int tslots);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) void slhc_free(struct slcompress *comp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) int slhc_compress(struct slcompress *comp, unsigned char *icp, int isize,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 		  unsigned char *ocp, unsigned char **cpp, int compress_cid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) int slhc_uncompress(struct slcompress *comp, unsigned char *icp, int isize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) int slhc_remember(struct slcompress *comp, unsigned char *icp, int isize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) int slhc_toss(struct slcompress *comp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) #endif	/* _SLHC_H */