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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/ax25/ax25_addr.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'net/ax25/ax25_addr.c')
-rw-r--r--net/ax25/ax25_addr.c290
1 files changed, 290 insertions, 0 deletions
diff --git a/net/ax25/ax25_addr.c b/net/ax25/ax25_addr.c
new file mode 100644
index 000000000000..f4fa6dfb846e
--- /dev/null
+++ b/net/ax25/ax25_addr.c
@@ -0,0 +1,290 @@
1/*
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.
6 *
7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 */
9#include <linux/errno.h>
10#include <linux/types.h>
11#include <linux/socket.h>
12#include <linux/in.h>
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/timer.h>
16#include <linux/string.h>
17#include <linux/sockios.h>
18#include <linux/net.h>
19#include <net/ax25.h>
20#include <linux/inet.h>
21#include <linux/netdevice.h>
22#include <linux/skbuff.h>
23#include <net/sock.h>
24#include <asm/uaccess.h>
25#include <asm/system.h>
26#include <linux/fcntl.h>
27#include <linux/mm.h>
28#include <linux/interrupt.h>
29
30/*
31 * The null address is defined as a callsign of all spaces with an
32 * SSID of zero.
33 */
34ax25_address null_ax25_address = {{0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x00}};
35
36/*
37 * ax25 -> ascii conversion
38 */
39char *ax2asc(ax25_address *a)
40{
41 static char buf[11];
42 char c, *s;
43 int n;
44
45 for (n = 0, s = buf; n < 6; n++) {
46 c = (a->ax25_call[n] >> 1) & 0x7F;
47
48 if (c != ' ') *s++ = c;
49 }
50
51 *s++ = '-';
52
53 if ((n = ((a->ax25_call[6] >> 1) & 0x0F)) > 9) {
54 *s++ = '1';
55 n -= 10;
56 }
57
58 *s++ = n + '0';
59 *s++ = '\0';
60
61 if (*buf == '\0' || *buf == '-')
62 return "*";
63
64 return buf;
65
66}
67
68/*
69 * ascii -> ax25 conversion
70 */
71ax25_address *asc2ax(char *callsign)
72{
73 static ax25_address addr;
74 char *s;
75 int n;
76
77 for (s = callsign, n = 0; n < 6; n++) {
78 if (*s != '\0' && *s != '-')
79 addr.ax25_call[n] = *s++;
80 else
81 addr.ax25_call[n] = ' ';
82 addr.ax25_call[n] <<= 1;
83 addr.ax25_call[n] &= 0xFE;
84 }
85
86 if (*s++ == '\0') {
87 addr.ax25_call[6] = 0x00;
88 return &addr;
89 }
90
91 addr.ax25_call[6] = *s++ - '0';
92
93 if (*s != '\0') {
94 addr.ax25_call[6] *= 10;
95 addr.ax25_call[6] += *s++ - '0';
96 }
97
98 addr.ax25_call[6] <<= 1;
99 addr.ax25_call[6] &= 0x1E;
100
101 return &addr;
102}
103
104/*
105 * Compare two ax.25 addresses
106 */
107int ax25cmp(ax25_address *a, ax25_address *b)
108{
109 int ct = 0;
110
111 while (ct < 6) {
112 if ((a->ax25_call[ct] & 0xFE) != (b->ax25_call[ct] & 0xFE)) /* Clean off repeater bits */
113 return 1;
114 ct++;
115 }
116
117 if ((a->ax25_call[ct] & 0x1E) == (b->ax25_call[ct] & 0x1E)) /* SSID without control bit */
118 return 0;
119
120 return 2; /* Partial match */
121}
122
123/*
124 * Compare two AX.25 digipeater paths.
125 */
126int ax25digicmp(ax25_digi *digi1, ax25_digi *digi2)
127{
128 int i;
129
130 if (digi1->ndigi != digi2->ndigi)
131 return 1;
132
133 if (digi1->lastrepeat != digi2->lastrepeat)
134 return 1;
135
136 for (i = 0; i < digi1->ndigi; i++)
137 if (ax25cmp(&digi1->calls[i], &digi2->calls[i]) != 0)
138 return 1;
139
140 return 0;
141}
142
143/*
144 * Given an AX.25 address pull of to, from, digi list, command/response and the start of data
145 *
146 */
147unsigned char *ax25_addr_parse(unsigned char *buf, int len, ax25_address *src, ax25_address *dest, ax25_digi *digi, int *flags, int *dama)
148{
149 int d = 0;
150
151 if (len < 14) return NULL;
152
153 if (flags != NULL) {
154 *flags = 0;
155
156 if (buf[6] & AX25_CBIT)
157 *flags = AX25_COMMAND;
158 if (buf[13] & AX25_CBIT)
159 *flags = AX25_RESPONSE;
160 }
161
162 if (dama != NULL)
163 *dama = ~buf[13] & AX25_DAMA_FLAG;
164
165 /* Copy to, from */
166 if (dest != NULL)
167 memcpy(dest, buf + 0, AX25_ADDR_LEN);
168 if (src != NULL)
169 memcpy(src, buf + 7, AX25_ADDR_LEN);
170
171 buf += 2 * AX25_ADDR_LEN;
172 len -= 2 * AX25_ADDR_LEN;
173
174 digi->lastrepeat = -1;
175 digi->ndigi = 0;
176
177 while (!(buf[-1] & AX25_EBIT)) {
178 if (d >= AX25_MAX_DIGIS) return NULL; /* Max of 6 digis */
179 if (len < 7) return NULL; /* Short packet */
180
181 memcpy(&digi->calls[d], buf, AX25_ADDR_LEN);
182 digi->ndigi = d + 1;
183
184 if (buf[6] & AX25_HBIT) {
185 digi->repeated[d] = 1;
186 digi->lastrepeat = d;
187 } else {
188 digi->repeated[d] = 0;
189 }
190
191 buf += AX25_ADDR_LEN;
192 len -= AX25_ADDR_LEN;
193 d++;
194 }
195
196 return buf;
197}
198
199/*
200 * Assemble an AX.25 header from the bits
201 */
202int ax25_addr_build(unsigned char *buf, ax25_address *src, ax25_address *dest, ax25_digi *d, int flag, int modulus)
203{
204 int len = 0;
205 int ct = 0;
206
207 memcpy(buf, dest, AX25_ADDR_LEN);
208 buf[6] &= ~(AX25_EBIT | AX25_CBIT);
209 buf[6] |= AX25_SSSID_SPARE;
210
211 if (flag == AX25_COMMAND) buf[6] |= AX25_CBIT;
212
213 buf += AX25_ADDR_LEN;
214 len += AX25_ADDR_LEN;
215
216 memcpy(buf, src, AX25_ADDR_LEN);
217 buf[6] &= ~(AX25_EBIT | AX25_CBIT);
218 buf[6] &= ~AX25_SSSID_SPARE;
219
220 if (modulus == AX25_MODULUS)
221 buf[6] |= AX25_SSSID_SPARE;
222 else
223 buf[6] |= AX25_ESSID_SPARE;
224
225 if (flag == AX25_RESPONSE) buf[6] |= AX25_CBIT;
226
227 /*
228 * Fast path the normal digiless path
229 */
230 if (d == NULL || d->ndigi == 0) {
231 buf[6] |= AX25_EBIT;
232 return 2 * AX25_ADDR_LEN;
233 }
234
235 buf += AX25_ADDR_LEN;
236 len += AX25_ADDR_LEN;
237
238 while (ct < d->ndigi) {
239 memcpy(buf, &d->calls[ct], AX25_ADDR_LEN);
240
241 if (d->repeated[ct])
242 buf[6] |= AX25_HBIT;
243 else
244 buf[6] &= ~AX25_HBIT;
245
246 buf[6] &= ~AX25_EBIT;
247 buf[6] |= AX25_SSSID_SPARE;
248
249 buf += AX25_ADDR_LEN;
250 len += AX25_ADDR_LEN;
251 ct++;
252 }
253
254 buf[-1] |= AX25_EBIT;
255
256 return len;
257}
258
259int ax25_addr_size(ax25_digi *dp)
260{
261 if (dp == NULL)
262 return 2 * AX25_ADDR_LEN;
263
264 return AX25_ADDR_LEN * (2 + dp->ndigi);
265}
266
267/*
268 * Reverse Digipeat List. May not pass both parameters as same struct
269 */
270void ax25_digi_invert(ax25_digi *in, ax25_digi *out)
271{
272 int ct;
273
274 out->ndigi = in->ndigi;
275 out->lastrepeat = in->ndigi - in->lastrepeat - 2;
276
277 /* Invert the digipeaters */
278 for (ct = 0; ct < in->ndigi; ct++) {
279 out->calls[ct] = in->calls[in->ndigi - ct - 1];
280
281 if (ct <= out->lastrepeat) {
282 out->calls[ct].ax25_call[6] |= AX25_HBIT;
283 out->repeated[ct] = 1;
284 } else {
285 out->calls[ct].ax25_call[6] &= ~AX25_HBIT;
286 out->repeated[ct] = 0;
287 }
288 }
289}
290