net/slip/slip.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * slip.h   Define the SLIP device driver interface and constants.
0004  *
0005  * NOTE:    THIS FILE WILL BE MOVED TO THE LINUX INCLUDE DIRECTORY
0006  *      AS SOON AS POSSIBLE!
0007  *
0008  * Version: @(#)slip.h  1.2.0   03/28/93
0009  *
0010  * Fixes:
0011  *      Alan Cox    :   Added slip mtu field.
0012  *      Matt Dillon :   Printable slip (borrowed from net2e)
0013  *      Alan Cox    :   Added SL_SLIP_LOTS
0014  *  Dmitry Gorodchanin  :   A lot of changes in the 'struct slip'
0015  *  Dmitry Gorodchanin  :   Added CSLIP statistics.
0016  *  Stanislav Voronyi   :   Make line checking as created by
0017  *                  Igor Chechik, RELCOM Corp.
0018  *  Craig Schlenter     :   Fixed #define bug that caused
0019  *                  CSLIP telnets to hang in 1.3.61-6
0020  *
0021  * Author:  Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
0022  */
0023 #ifndef _LINUX_SLIP_H
0024 #define _LINUX_SLIP_H
0025
0026
0027 #if defined(CONFIG_INET) && defined(CONFIG_SLIP_COMPRESSED)
0028 # define SL_INCLUDE_CSLIP
0029 #endif
0030
0031 #ifdef SL_INCLUDE_CSLIP
0032 # define SL_MODE_DEFAULT SL_MODE_ADAPTIVE
0033 #else
0034 # define SL_MODE_DEFAULT SL_MODE_SLIP
0035 #endif
0036
0037 /* SLIP configuration. */
0038 #define SL_NRUNIT   256     /* MAX number of SLIP channels;
0039                        This can be overridden with
0040                        insmod -oslip_maxdev=nnn */
0041 #define SL_MTU      296     /* 296; I am used to 600- FvK   */
0042
0043 /* some arch define END as assembly function ending, just undef it */
0044 #undef  END
0045 /* SLIP protocol characters. */
0046 #define END             0300        /* indicates end of frame   */
0047 #define ESC             0333        /* indicates byte stuffing  */
0048 #define ESC_END         0334        /* ESC ESC_END means END 'data' */
0049 #define ESC_ESC         0335        /* ESC ESC_ESC means ESC 'data' */
0050
0051
0052 struct slip {
0053   int           magic;
0054
0055   /* Various fields. */
0056   struct tty_struct *tty;       /* ptr to TTY structure     */
0057   struct net_device *dev;       /* easy for intr handling   */
0058   spinlock_t        lock;
0059   struct work_struct    tx_work;    /* Flushes transmit buffer  */
0060
0061 #ifdef SL_INCLUDE_CSLIP
0062   struct slcompress *slcomp;    /* for header compression   */
0063   unsigned char     *cbuff;     /* compression buffer       */
0064 #endif
0065
0066   /* These are pointers to the malloc()ed frame buffers. */
0067   unsigned char     *rbuff;     /* receiver buffer      */
0068   int                   rcount;         /* received chars counter       */
0069   unsigned char     *xbuff;     /* transmitter buffer       */
0070   unsigned char         *xhead;         /* pointer to next byte to XMIT */
0071   int                   xleft;          /* bytes left in XMIT queue     */
0072   int           mtu;        /* Our mtu (to spot changes!)   */
0073   int                   buffsize;       /* Max buffers sizes            */
0074
0075 #ifdef CONFIG_SLIP_MODE_SLIP6
0076   int           xdata, xbits;   /* 6 bit slip controls      */
0077 #endif
0078
0079   unsigned long     flags;      /* Flag values/ mode etc    */
0080 #define SLF_INUSE   0       /* Channel in use               */
0081 #define SLF_ESCAPE  1               /* ESC received                 */
0082 #define SLF_ERROR   2               /* Parity, etc. error           */
0083 #define SLF_KEEPTEST    3       /* Keepalive test flag      */
0084 #define SLF_OUTWAIT 4       /* is outpacket was flag    */
0085
0086   unsigned char     mode;       /* SLIP mode            */
0087   unsigned char     leased;
0088   pid_t         pid;
0089 #define SL_MODE_SLIP    0
0090 #define SL_MODE_CSLIP   1
0091 #define SL_MODE_SLIP6   2       /* Matt Dillon's printable slip */
0092 #define SL_MODE_CSLIP6  (SL_MODE_SLIP6|SL_MODE_CSLIP)
0093 #define SL_MODE_AX25    4
0094 #define SL_MODE_ADAPTIVE 8
0095 #ifdef CONFIG_SLIP_SMART
0096   unsigned char     outfill;    /* # of sec between outfill packet */
0097   unsigned char     keepalive;  /* keepalive seconds        */
0098   struct timer_list outfill_timer;
0099   struct timer_list keepalive_timer;
0100 #endif
0101 };
0102
0103 #define SLIP_MAGIC 0x5302
0104
0105 #endif  /* _LINUX_SLIP.H */