2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
9 #include <linux/errno.h>
10 #include <linux/types.h>
11 #include <linux/socket.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/timer.h>
16 #include <linux/string.h>
17 #include <linux/sockios.h>
18 #include <linux/net.h>
20 #include <linux/inet.h>
21 #include <linux/netdevice.h>
22 #include <linux/skbuff.h>
24 #include <asm/uaccess.h>
25 #include <linux/fcntl.h>
27 #include <linux/interrupt.h>
30 * The default broadcast address of an interface is QST-0; the default address
31 * is LINUX-1. The null address is defined as a callsign of all spaces with
35 const ax25_address ax25_bcast
=
36 {{'Q' << 1, 'S' << 1, 'T' << 1, ' ' << 1, ' ' << 1, ' ' << 1, 0 << 1}};
37 const ax25_address ax25_defaddr
=
38 {{'L' << 1, 'I' << 1, 'N' << 1, 'U' << 1, 'X' << 1, ' ' << 1, 1 << 1}};
39 const ax25_address null_ax25_address
=
40 {{' ' << 1, ' ' << 1, ' ' << 1, ' ' << 1, ' ' << 1, ' ' << 1, 0 << 1}};
42 EXPORT_SYMBOL_GPL(ax25_bcast
);
43 EXPORT_SYMBOL_GPL(ax25_defaddr
);
44 EXPORT_SYMBOL(null_ax25_address
);
47 * ax25 -> ascii conversion
49 char *ax2asc(char *buf
, const ax25_address
*a
)
54 for (n
= 0, s
= buf
; n
< 6; n
++) {
55 c
= (a
->ax25_call
[n
] >> 1) & 0x7F;
57 if (c
!= ' ') *s
++ = c
;
62 if ((n
= ((a
->ax25_call
[6] >> 1) & 0x0F)) > 9) {
70 if (*buf
== '\0' || *buf
== '-')
77 EXPORT_SYMBOL(ax2asc
);
80 * ascii -> ax25 conversion
82 void asc2ax(ax25_address
*addr
, const char *callsign
)
87 for (s
= callsign
, n
= 0; n
< 6; n
++) {
88 if (*s
!= '\0' && *s
!= '-')
89 addr
->ax25_call
[n
] = *s
++;
91 addr
->ax25_call
[n
] = ' ';
92 addr
->ax25_call
[n
] <<= 1;
93 addr
->ax25_call
[n
] &= 0xFE;
97 addr
->ax25_call
[6] = 0x00;
101 addr
->ax25_call
[6] = *s
++ - '0';
104 addr
->ax25_call
[6] *= 10;
105 addr
->ax25_call
[6] += *s
++ - '0';
108 addr
->ax25_call
[6] <<= 1;
109 addr
->ax25_call
[6] &= 0x1E;
112 EXPORT_SYMBOL(asc2ax
);
115 * Compare two ax.25 addresses
117 int ax25cmp(const ax25_address
*a
, const ax25_address
*b
)
122 if ((a
->ax25_call
[ct
] & 0xFE) != (b
->ax25_call
[ct
] & 0xFE)) /* Clean off repeater bits */
127 if ((a
->ax25_call
[ct
] & 0x1E) == (b
->ax25_call
[ct
] & 0x1E)) /* SSID without control bit */
130 return 2; /* Partial match */
133 EXPORT_SYMBOL(ax25cmp
);
136 * Compare two AX.25 digipeater paths.
138 int ax25digicmp(const ax25_digi
*digi1
, const ax25_digi
*digi2
)
142 if (digi1
->ndigi
!= digi2
->ndigi
)
145 if (digi1
->lastrepeat
!= digi2
->lastrepeat
)
148 for (i
= 0; i
< digi1
->ndigi
; i
++)
149 if (ax25cmp(&digi1
->calls
[i
], &digi2
->calls
[i
]) != 0)
156 * Given an AX.25 address pull of to, from, digi list, command/response and the start of data
159 const unsigned char *ax25_addr_parse(const unsigned char *buf
, int len
,
160 ax25_address
*src
, ax25_address
*dest
, ax25_digi
*digi
, int *flags
,
165 if (len
< 14) return NULL
;
170 if (buf
[6] & AX25_CBIT
)
171 *flags
= AX25_COMMAND
;
172 if (buf
[13] & AX25_CBIT
)
173 *flags
= AX25_RESPONSE
;
177 *dama
= ~buf
[13] & AX25_DAMA_FLAG
;
181 memcpy(dest
, buf
+ 0, AX25_ADDR_LEN
);
183 memcpy(src
, buf
+ 7, AX25_ADDR_LEN
);
185 buf
+= 2 * AX25_ADDR_LEN
;
186 len
-= 2 * AX25_ADDR_LEN
;
188 digi
->lastrepeat
= -1;
191 while (!(buf
[-1] & AX25_EBIT
)) {
192 if (d
>= AX25_MAX_DIGIS
) return NULL
; /* Max of 6 digis */
193 if (len
< 7) return NULL
; /* Short packet */
195 memcpy(&digi
->calls
[d
], buf
, AX25_ADDR_LEN
);
198 if (buf
[6] & AX25_HBIT
) {
199 digi
->repeated
[d
] = 1;
200 digi
->lastrepeat
= d
;
202 digi
->repeated
[d
] = 0;
205 buf
+= AX25_ADDR_LEN
;
206 len
-= AX25_ADDR_LEN
;
214 * Assemble an AX.25 header from the bits
216 int ax25_addr_build(unsigned char *buf
, const ax25_address
*src
,
217 const ax25_address
*dest
, const ax25_digi
*d
, int flag
, int modulus
)
222 memcpy(buf
, dest
, AX25_ADDR_LEN
);
223 buf
[6] &= ~(AX25_EBIT
| AX25_CBIT
);
224 buf
[6] |= AX25_SSSID_SPARE
;
226 if (flag
== AX25_COMMAND
) buf
[6] |= AX25_CBIT
;
228 buf
+= AX25_ADDR_LEN
;
229 len
+= AX25_ADDR_LEN
;
231 memcpy(buf
, src
, AX25_ADDR_LEN
);
232 buf
[6] &= ~(AX25_EBIT
| AX25_CBIT
);
233 buf
[6] &= ~AX25_SSSID_SPARE
;
235 if (modulus
== AX25_MODULUS
)
236 buf
[6] |= AX25_SSSID_SPARE
;
238 buf
[6] |= AX25_ESSID_SPARE
;
240 if (flag
== AX25_RESPONSE
) buf
[6] |= AX25_CBIT
;
243 * Fast path the normal digiless path
245 if (d
== NULL
|| d
->ndigi
== 0) {
247 return 2 * AX25_ADDR_LEN
;
250 buf
+= AX25_ADDR_LEN
;
251 len
+= AX25_ADDR_LEN
;
253 while (ct
< d
->ndigi
) {
254 memcpy(buf
, &d
->calls
[ct
], AX25_ADDR_LEN
);
259 buf
[6] &= ~AX25_HBIT
;
261 buf
[6] &= ~AX25_EBIT
;
262 buf
[6] |= AX25_SSSID_SPARE
;
264 buf
+= AX25_ADDR_LEN
;
265 len
+= AX25_ADDR_LEN
;
269 buf
[-1] |= AX25_EBIT
;
274 int ax25_addr_size(const ax25_digi
*dp
)
277 return 2 * AX25_ADDR_LEN
;
279 return AX25_ADDR_LEN
* (2 + dp
->ndigi
);
283 * Reverse Digipeat List. May not pass both parameters as same struct
285 void ax25_digi_invert(const ax25_digi
*in
, ax25_digi
*out
)
289 out
->ndigi
= in
->ndigi
;
290 out
->lastrepeat
= in
->ndigi
- in
->lastrepeat
- 2;
292 /* Invert the digipeaters */
293 for (ct
= 0; ct
< in
->ndigi
; ct
++) {
294 out
->calls
[ct
] = in
->calls
[in
->ndigi
- ct
- 1];
296 if (ct
<= out
->lastrepeat
) {
297 out
->calls
[ct
].ax25_call
[6] |= AX25_HBIT
;
298 out
->repeated
[ct
] = 1;
300 out
->calls
[ct
].ax25_call
[6] &= ~AX25_HBIT
;
301 out
->repeated
[ct
] = 0;