1 /*
2  * slip.h	Define the SLIP device driver interface and constants.
3  *
4  * NOTE:	THIS FILE WILL BE MOVED TO THE LINUX INCLUDE DIRECTORY
5  *		AS SOON AS POSSIBLE!
6  *
7  * Version:	@(#)slip.h	1.2.0	03/28/93
8  *
9  * Fixes:
10  *		Alan Cox	: 	Added slip mtu field.
11  *		Matt Dillon	:	Printable slip (borrowed from net2e)
12  *		Alan Cox	:	Added SL_SLIP_LOTS
13  *	Dmitry Gorodchanin	:	A lot of changes in the 'struct slip'
14  *	Dmitry Gorodchanin	:	Added CSLIP statistics.
15  *	Stanislav Voronyi	:	Make line checking as created by
16  *					Igor Chechik, RELCOM Corp.
17  *	Craig Schlenter		:	Fixed #define bug that caused
18  *					CSLIP telnets to hang in 1.3.61-6
19  *
20  * Author:	Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
21  */
22 #ifndef _LINUX_SLIP_H
23 #define _LINUX_SLIP_H
24 
25 #include <linux/config.h>
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 
58 #ifdef SL_INCLUDE_CSLIP
59   struct slcompress	*slcomp;	/* for header compression 	*/
60   unsigned char		*cbuff;		/* compression buffer		*/
61 #endif
62 
63   /* These are pointers to the malloc()ed frame buffers. */
64   unsigned char		*rbuff;		/* receiver buffer		*/
65   int                   rcount;         /* received chars counter       */
66   unsigned char		*xbuff;		/* transmitter buffer		*/
67   unsigned char         *xhead;         /* pointer to next byte to XMIT */
68   int                   xleft;          /* bytes left in XMIT queue     */
69 
70   /* SLIP interface statistics. */
71   unsigned long		rx_packets;	/* inbound frames counter	*/
72   unsigned long         tx_packets;     /* outbound frames counter      */
73   unsigned long		rx_bytes;	/* inbound byte counte		*/
74   unsigned long         tx_bytes;       /* outbound byte counter	*/
75   unsigned long         rx_errors;      /* Parity, etc. errors          */
76   unsigned long         tx_errors;      /* Planned stuff                */
77   unsigned long         rx_dropped;     /* No memory for skb            */
78   unsigned long         tx_dropped;     /* When MTU change              */
79   unsigned long         rx_over_errors; /* Frame bigger then SLIP buf.  */
80 #ifdef SL_INCLUDE_CSLIP
81   unsigned long		tx_compressed;
82   unsigned long		rx_compressed;
83   unsigned long		tx_misses;
84 #endif
85   /* Detailed SLIP statistics. */
86 
87   int			mtu;		/* Our mtu (to spot changes!)   */
88   int                   buffsize;       /* Max buffers sizes            */
89 
90 #ifdef CONFIG_SLIP_MODE_SLIP6
91   int			xdata, xbits;	/* 6 bit slip controls 		*/
92 #endif
93 
94   unsigned long		flags;		/* Flag values/ mode etc	*/
95 #define SLF_INUSE	0		/* Channel in use               */
96 #define SLF_ESCAPE	1               /* ESC received                 */
97 #define SLF_ERROR	2               /* Parity, etc. error           */
98 #define SLF_KEEPTEST	3		/* Keepalive test flag		*/
99 #define SLF_OUTWAIT	4		/* is outpacket was flag	*/
100 
101   unsigned char		mode;		/* SLIP mode			*/
102   unsigned char		leased;
103   kdev_t		line;
104   pid_t			pid;
105 #define SL_MODE_SLIP	0
106 #define SL_MODE_CSLIP	1
107 #define SL_MODE_SLIP6	2		/* Matt Dillon's printable slip */
108 #define SL_MODE_CSLIP6	(SL_MODE_SLIP6|SL_MODE_CSLIP)
109 #define SL_MODE_AX25	4
110 #define SL_MODE_ADAPTIVE 8
111 #ifdef CONFIG_SLIP_SMART
112   unsigned char		outfill;	/* # of sec between outfill packet */
113   unsigned char		keepalive;	/* keepalive seconds		*/
114   struct timer_list	outfill_timer;
115   struct timer_list	keepalive_timer;
116 #endif
117 };
118 
119 
120 
121 #define SLIP_MAGIC 0x5302
122 
123 extern int slip_init(struct net_device *dev);
124 
125 #endif	/* _LINUX_SLIP.H */
126