1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * slip.h Define the SLIP device driver interface and constants. 4 * 5 * NOTE: THIS FILE WILL BE MOVED TO THE LINUX INCLUDE DIRECTORY 6 * AS SOON AS POSSIBLE! 7 * 8 * Version: @(#)slip.h 1.2.0 03/28/93 9 * 10 * Fixes: 11 * Alan Cox : Added slip mtu field. 12 * Matt Dillon : Printable slip (borrowed from net2e) 13 * Alan Cox : Added SL_SLIP_LOTS 14 * Dmitry Gorodchanin : A lot of changes in the 'struct slip' 15 * Dmitry Gorodchanin : Added CSLIP statistics. 16 * Stanislav Voronyi : Make line checking as created by 17 * Igor Chechik, RELCOM Corp. 18 * Craig Schlenter : Fixed #define bug that caused 19 * CSLIP telnets to hang in 1.3.61-6 20 * 21 * Author: Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org> 22 */ 23 #ifndef _LINUX_SLIP_H 24 #define _LINUX_SLIP_H 25 26 27 #if defined(CONFIG_INET) && defined(CONFIG_SLIP_COMPRESSED) 28 # define SL_INCLUDE_CSLIP 29 #endif 30 31 #ifdef SL_INCLUDE_CSLIP 32 # define SL_MODE_DEFAULT SL_MODE_ADAPTIVE 33 #else 34 # define SL_MODE_DEFAULT SL_MODE_SLIP 35 #endif 36 37 /* SLIP configuration. */ 38 #define SL_NRUNIT 256 /* MAX number of SLIP channels; 39 This can be overridden with 40 insmod -oslip_maxdev=nnn */ 41 #define SL_MTU 296 /* 296; I am used to 600- FvK */ 42 43 /* SLIP protocol characters. */ 44 #define END 0300 /* indicates end of frame */ 45 #define ESC 0333 /* indicates byte stuffing */ 46 #define ESC_END 0334 /* ESC ESC_END means END 'data' */ 47 #define ESC_ESC 0335 /* ESC ESC_ESC means ESC 'data' */ 48 49 50 struct slip { 51 int magic; 52 53 /* Various fields. */ 54 struct tty_struct *tty; /* ptr to TTY structure */ 55 struct net_device *dev; /* easy for intr handling */ 56 spinlock_t lock; 57 struct work_struct tx_work; /* Flushes transmit buffer */ 58 59 #ifdef SL_INCLUDE_CSLIP 60 struct slcompress *slcomp; /* for header compression */ 61 unsigned char *cbuff; /* compression buffer */ 62 #endif 63 64 /* These are pointers to the malloc()ed frame buffers. */ 65 unsigned char *rbuff; /* receiver buffer */ 66 int rcount; /* received chars counter */ 67 unsigned char *xbuff; /* transmitter buffer */ 68 unsigned char *xhead; /* pointer to next byte to XMIT */ 69 int xleft; /* bytes left in XMIT queue */ 70 int mtu; /* Our mtu (to spot changes!) */ 71 int buffsize; /* Max buffers sizes */ 72 73 #ifdef CONFIG_SLIP_MODE_SLIP6 74 int xdata, xbits; /* 6 bit slip controls */ 75 #endif 76 77 unsigned long flags; /* Flag values/ mode etc */ 78 #define SLF_INUSE 0 /* Channel in use */ 79 #define SLF_ESCAPE 1 /* ESC received */ 80 #define SLF_ERROR 2 /* Parity, etc. error */ 81 #define SLF_KEEPTEST 3 /* Keepalive test flag */ 82 #define SLF_OUTWAIT 4 /* is outpacket was flag */ 83 84 unsigned char mode; /* SLIP mode */ 85 unsigned char leased; 86 pid_t pid; 87 #define SL_MODE_SLIP 0 88 #define SL_MODE_CSLIP 1 89 #define SL_MODE_SLIP6 2 /* Matt Dillon's printable slip */ 90 #define SL_MODE_CSLIP6 (SL_MODE_SLIP6|SL_MODE_CSLIP) 91 #define SL_MODE_AX25 4 92 #define SL_MODE_ADAPTIVE 8 93 #ifdef CONFIG_SLIP_SMART 94 unsigned char outfill; /* # of sec between outfill packet */ 95 unsigned char keepalive; /* keepalive seconds */ 96 struct timer_list outfill_timer; 97 struct timer_list keepalive_timer; 98 #endif 99 }; 100 101 #define SLIP_MAGIC 0x5302 102 103 #endif /* _LINUX_SLIP.H */ 104