1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
/* kiss.c KISS assembly and byte-stuffing stuff
*
* Copyright 1991, Michael Westerhof, Sun Microsystems, Inc.
* This software may be freely used, distributed, or modified, providing
* this header is not removed.
*
* This is the only module that knows about the internal structure of
* KISS frames.
*/
/*
* dual port changes Feb 95 ve3pnx & ve3djf
*/
#include <stdio.h>
#include <syslog.h>
#include "ax25ipd.h"
#define FEND 0xc0
#define FESC 0xdb
#define TFEND 0xdc
#define TFESC 0xdd
unsigned char iframe[MAX_FRAME];
unsigned char *ifptr;
int ifcount;
int iescaped;
unsigned char oframe[MAX_FRAME];
unsigned char *ofptr;
int ofcount;
#define PTABLE_SIZE 10
struct param_table_entry {
unsigned char parameter;
unsigned char value;
} param_tbl[PTABLE_SIZE];
int param_tbl_top;
/*
* Initialize the KISS variables
*/
void kiss_init(void)
{
ifptr = iframe;
ifcount = 0;
iescaped = 0;
ofptr = oframe;
ofcount = 0;
param_tbl_top = 0;
}
/*
* Assemble a kiss frame from random hunks of incoming data
* Calls the "from_kiss" routine with the kiss frame when a
* frame has been assembled.
*/
void assemble_kiss(unsigned char *buf, int l)
{
int i;
unsigned char c;
for (i = 0; i < l; i++, buf++) {
c = *buf;
if (c == FEND) {
if (ifcount > 0) {
/* Make sure that the control byte is zero */
if (*iframe == '\0' || *iframe == 0x10) {
/* Room for CRC in buffer? */
if (ifcount < (MAX_FRAME - 2)) {
stats.kiss_in++;
from_kiss(iframe +
1, ifcount - 1);
} else {
stats.kiss_toobig++;
LOGL2
("assemble_kiss: dumped - frame too large\n");
}
} else {
stats.kiss_badtype++;
LOGL2
("assemble_kiss: dumped - control byte non-zero\n");
}
}
ifcount = 0;
iescaped = 0;
ifptr = iframe;
continue;
}
if (c == FESC) {
iescaped = 1;
continue;
}
if (iescaped) {
if (c == TFEND)
c = FEND;
if (c == TFESC)
c = FESC;
iescaped = 0;
}
if (ifcount < MAX_FRAME) {
*ifptr = c;
ifptr++;
ifcount++;
}
} /* for every character in the buffer */
}
/* convert a standard AX25 frame into a kiss frame */
void send_kiss(unsigned char type, unsigned char *buf, int l)
{
#define KISSEMIT(x) if(ofcount<MAX_FRAME){*ofptr=(x);ofptr++;ofcount++;}
int i;
ofptr = oframe;
ofcount = 0;
KISSEMIT(FEND);
if (type == FEND) {
KISSEMIT(FESC);
KISSEMIT(TFEND);
} else if (type == FESC) {
KISSEMIT(FESC);
KISSEMIT(TFESC);
} else {
KISSEMIT(type);
}
for (i = 0; i < l; i++, buf++) {
if (*buf == FEND) {
KISSEMIT(FESC);
KISSEMIT(TFEND);
} else if (*buf == FESC) {
KISSEMIT(FESC);
KISSEMIT(TFESC);
} else {
KISSEMIT(*buf);
}
} /* for each character in the incoming AX25 frame */
KISSEMIT(FEND);
send_tty(oframe, ofcount);
}
/* Add an entry to the parameter table */
void param_add(int p, int v)
{
if (param_tbl_top >= PTABLE_SIZE) {
fprintf(stderr, "param table is full; entry ignored.\n");
}
param_tbl[param_tbl_top].parameter = p & 0xff;
param_tbl[param_tbl_top].value = v & 0xff;
LOGL4("added param: %d\t%d\n",
param_tbl[param_tbl_top].parameter,
param_tbl[param_tbl_top].value);
param_tbl_top++;
return;
}
/* dump the contents of the parameter table */
void dump_params(void)
{
int i;
LOGL1("\n%d parameters\n", param_tbl_top);
for (i = 0; i < param_tbl_top; i++) {
LOGL1(" %d\t%d\n",
param_tbl[i].parameter, param_tbl[i].value);
}
fflush(stdout);
}
/* send the parameters to the TNC */
void send_params(void)
{
int i;
unsigned char p, v;
for (i = 0; i < param_tbl_top; i++) {
p = param_tbl[i].parameter;
v = param_tbl[i].value;
send_kiss(p, &v, 1);
LOGL2("send_params: param %d %d\n", p, v);
}
}
|
