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 */