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Diffstat (limited to 'include/openbsc/slhc.h')
| -rw-r--r-- | include/openbsc/slhc.h | 187 |
1 files changed, 0 insertions, 187 deletions
diff --git a/include/openbsc/slhc.h b/include/openbsc/slhc.h deleted file mode 100644 index cd5a47cf4..000000000 --- a/include/openbsc/slhc.h +++ /dev/null @@ -1,187 +0,0 @@ -#ifndef _SLHC_H -#define _SLHC_H -/* - * Definitions for tcp compression routines. - * - * $Header: slcompress.h,v 1.10 89/12/31 08:53:02 van 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 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. - * - * Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989: - * - Initial distribution. - * - * - * modified for KA9Q Internet Software Package by - * Katie Stevens (dkstevens@ucdavis.edu) - * University of California, Davis - * Computing Services - * - 01-31-90 initial adaptation - * - * - Feb 1991 Bill_Simpson@um.cc.umich.edu - * variable number of conversation slots - * allow zero or one slots - * separate routines - * status display - */ - -/* - * 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, - * acknowledgment, 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". - */ - - -#include <linux/ip.h> -#include <linux/tcp.h> - -/* SLIP compression masks for len/vers byte */ -#define SL_TYPE_IP 0x40 -#define SL_TYPE_UNCOMPRESSED_TCP 0x70 -#define SL_TYPE_COMPRESSED_TCP 0x80 -#define SL_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 - -/* - * data type and sizes conversion assumptions: - * - * VJ code KA9Q style generic - * u_char byte_t unsigned char 8 bits - * u_short int16 unsigned short 16 bits - * u_int int16 unsigned short 16 bits - * u_long unsigned long unsigned long 32 bits - * int int32 long 32 bits - */ - -typedef __u8 byte_t; -typedef __u32 int32; - -/* - * "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 { - byte_t cs_this; /* connection id number (xmit) */ - struct cstate *next; /* next in ring (xmit) */ - struct iphdr cs_ip; /* ip/tcp hdr from most recent packet */ - struct tcphdr cs_tcp; - unsigned char cs_ipopt[64]; - unsigned char cs_tcpopt[64]; - int cs_hsize; -}; -#define NULLSLSTATE (struct cstate *)0 - -/* - * all the state data for one serial line (we need one of these per line). - */ -struct slcompress { - struct cstate *tstate; /* transmit connection states (array)*/ - struct cstate *rstate; /* receive connection states (array)*/ - - byte_t tslot_limit; /* highest transmit slot id (0-l)*/ - byte_t rslot_limit; /* highest receive slot id (0-l)*/ - - byte_t xmit_oldest; /* oldest xmit in ring */ - byte_t xmit_current; /* most recent xmit id */ - byte_t recv_current; /* most recent rcvd id */ - - byte_t flags; -#define SLF_TOSS 0x01 /* tossing rcvd frames until id received */ - - int32 sls_o_nontcp; /* outbound non-TCP packets */ - int32 sls_o_tcp; /* outbound TCP packets */ - int32 sls_o_uncompressed; /* outbound uncompressed packets */ - int32 sls_o_compressed; /* outbound compressed packets */ - int32 sls_o_searches; /* searches for connection state */ - int32 sls_o_misses; /* times couldn't find conn. state */ - - int32 sls_i_uncompressed; /* inbound uncompressed packets */ - int32 sls_i_compressed; /* inbound compressed packets */ - int32 sls_i_error; /* inbound error packets */ - int32 sls_i_tossed; /* inbound packets tossed because of error */ - - int32 sls_i_runt; - int32 sls_i_badcheck; -}; -#define NULLSLCOMPR (struct slcompress *)0 - -/* In slhc.c: */ -struct slcompress *slhc_init(const void *ctx, int rslots, int tslots); - -void slhc_free(struct slcompress *comp); - -int slhc_compress(struct slcompress *comp, unsigned char *icp, int isize, - unsigned char *ocp, unsigned char **cpp, int compress_cid); -int slhc_uncompress(struct slcompress *comp, unsigned char *icp, int isize); -int slhc_remember(struct slcompress *comp, unsigned char *icp, int isize); -int slhc_toss(struct slcompress *comp); - -void slhc_i_status(struct slcompress *comp); -void slhc_o_status(struct slcompress *comp); - -#endif /* _SLHC_H */ |