tsiry-sandratraina.com
A modern Music Player Daemon based on Rockbox open source high quality audio player
libadwaita
audio
rust
zig
deno
mpris
rockbox
mpd
1/***************************************************************************
2 * __________ __ ___.
3 * Open \______ \ ____ ____ | | _\_ |__ _______ ___
4 * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
5 * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
6 * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
7 * \/ \/ \/ \/ \/
8 * $Id$
9 *
10 * Copyright (C) 2002 by Björn Stenberg
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version 2
15 * of the License, or (at your option) any later version.
16 *
17 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
18 * KIND, either express or implied.
19 *
20 ****************************************************************************/
21
22#include <stdio.h>
23#include <stdlib.h>
24#include <string.h>
25
26#include "iriver.h"
27#include "gigabeat.h"
28
29int iaudio_decode(char *iname, char *oname);
30
31unsigned int le2int(unsigned char* buf)
32{
33 unsigned int res = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
34
35 return res;
36}
37
38void int2le(unsigned int val, unsigned char* addr)
39{
40 addr[0] = val & 0xFF;
41 addr[1] = (val >> 8) & 0xff;
42 addr[2] = (val >> 16) & 0xff;
43 addr[3] = (val >> 24) & 0xff;
44}
45
46void usage(void)
47{
48 printf("usage: descramble [options] <input file> <output file>\n");
49 printf("options:\n"
50 "\t-fm Archos FM recorder format\n"
51 "\t-v2 Archos V2 recorder format\n"
52 "\t-mm Archos Multimedia format\n"
53 "\t-iriver iRiver format\n"
54 "\t-gigabeat Toshiba Gigabeat format\n"
55 "\t-iaudio iAudio format\n"
56 "\nNo option assumes Archos standard player/recorder format.\n");
57 exit(1);
58}
59
60int main (int argc, char** argv)
61{
62 unsigned long length,i,slen;
63 unsigned char *inbuf,*outbuf;
64 char *iname = argv[1];
65 char *oname = argv[2];
66 unsigned char header[32];
67 int headerlen = 6;
68 int descramble = 1;
69 FILE* file;
70
71 if (argc < 3) {
72 usage();
73 }
74
75 if (!strcmp(argv[1], "-fm") || !strcmp(argv[1], "-v2")) {
76 headerlen = 24;
77 iname = argv[2];
78 oname = argv[3];
79 }
80
81 if (!strcmp(argv[1], "-mm")) {
82 headerlen = 16;
83 iname = argv[2];
84 oname = argv[3];
85 descramble = 0;
86 }
87
88 if(!strcmp(argv[1], "-iriver")) {
89 /* iRiver code dealt with in the iriver.c code */
90 iname = argv[2];
91 oname = argv[3];
92 return iriver_decode(iname, oname, FALSE, STRIP_NONE) ? -1 : 0;
93 }
94 if(!strcmp(argv[1], "-gigabeat")) {
95 iname = argv[2];
96 oname = argv[3];
97 gigabeat_code(iname, oname);
98 return 0;
99 }
100
101 if(!strcmp(argv[1], "-iaudio")) {
102 iname = argv[2];
103 oname = argv[3];
104 return iaudio_decode(iname, oname);
105 }
106
107 /* open file and check size */
108 file = fopen(iname,"rb");
109 if (!file) {
110 perror(iname);
111 return -1;
112 }
113 fseek(file,0,SEEK_END);
114 length = ftell(file) - headerlen; /* skip header */
115 fseek(file,0,SEEK_SET);
116 i = fread(header, 1, headerlen, file);
117 if ( !i ) {
118 perror(iname);
119 return -1;
120 }
121
122 inbuf = malloc(length);
123 outbuf = malloc(length);
124 if ( !inbuf || !outbuf ) {
125 printf("out of memory!\n");
126 return -1;
127 }
128
129 /* read file */
130 i=fread(inbuf,1,length,file);
131 if ( !i ) {
132 perror(iname);
133 return -1;
134 }
135 fclose(file);
136
137 if (descramble) {
138 /* descramble */
139 slen = length/4;
140 for (i = 0; i < length; i++) {
141 unsigned long addr = ((i % slen) << 2) + i/slen;
142 unsigned char data = inbuf[i];
143 data = ~((data >> 1) | ((data << 7) & 0x80)); /* poor man's ROR */
144 outbuf[addr] = data;
145 }
146 }
147 else {
148 void* tmpptr;
149 unsigned int j=0;
150 int stringlen = 32;
151 int unpackedsize;
152 unsigned char xorstring[32];
153
154 unpackedsize = header[4] | header[5] << 8;
155 unpackedsize |= header[6] << 16 | header[7] << 24;
156
157 length = header[8] | header[9] << 8;
158 length |= header[10] << 16 | header[11] << 24;
159
160 /* calculate the xor string used */
161 for (i=0; i<(unsigned long)stringlen; i++) {
162 int top=0, topchar=0, c;
163 int bytecount[256];
164 memset(bytecount, 0, sizeof(bytecount));
165
166 /* gather byte frequency statistics */
167 for (c=i; c<(int)length; c+=stringlen)
168 bytecount[inbuf[c]]++;
169
170 /* find the most frequent byte */
171 for (c=0; c<256; c++) {
172 if (bytecount[c] > top) {
173 top = bytecount[c];
174 topchar = c;
175 }
176 }
177 xorstring[i] = topchar;
178 }
179 printf("XOR string: %.*s\n", stringlen, xorstring);
180
181 /* xor the buffer */
182 for (i=0; i<length; i++)
183 outbuf[i] = inbuf[i] ^ xorstring[i & (stringlen-1)];
184
185 /* unpack */
186 tmpptr = realloc(inbuf, unpackedsize);
187 memset(tmpptr, 0, unpackedsize);
188 inbuf = outbuf;
189 outbuf = tmpptr;
190
191 for (i=0; i<length;) {
192 int bit;
193 int head = inbuf[i++];
194
195 for (bit=0; bit<8 && i<length; bit++) {
196 if (head & (1 << (bit))) {
197 outbuf[j++] = inbuf[i++];
198 }
199 else {
200 int x;
201 int byte1 = inbuf[i];
202 int byte2 = inbuf[i+1];
203 int count = (byte2 & 0x0f) + 3;
204 int src =
205 (j & 0xfffff000) + (byte1 | ((byte2 & 0xf0)<<4)) + 18;
206 if (src > (int)j)
207 src -= 0x1000;
208
209 for (x=0; x<count; x++)
210 outbuf[j++] = outbuf[src+x];
211 i += 2;
212 }
213 }
214 }
215 length = j;
216 }
217
218 /* write file */
219 file = fopen(oname,"wb");
220 if ( !file ) {
221 perror(argv[2]);
222 return -1;
223 }
224 if ( !fwrite(outbuf,length,1,file) ) {
225 perror(argv[2]);
226 return -1;
227 }
228 fclose(file);
229
230 free(inbuf);
231 free(outbuf);
232
233 return 0;
234}
235
236int iaudio_decode(char *iname, char *oname)
237{
238 size_t len;
239 int length;
240 FILE *file;
241 char *outbuf;
242 int i;
243 unsigned char sum = 0;
244 unsigned char filesum;
245
246 file = fopen(iname, "rb");
247 if (!file) {
248 perror(iname);
249 return -1;
250 }
251 fseek(file,0,SEEK_END);
252 length = ftell(file);
253
254 fseek(file,0,SEEK_SET);
255 outbuf = malloc(length);
256
257 if ( !outbuf ) {
258 printf("out of memory!\n");
259 return -1;
260 }
261
262 len = fread(outbuf, 1, length, file);
263 if(len < (size_t)length) {
264 perror(iname);
265 return -2;
266 }
267
268 fclose(file);
269
270 for(i = 0; i < length-0x1030;i++)
271 sum += outbuf[0x1030 + i];
272
273 filesum = outbuf[0x102b];
274
275 if(filesum != sum) {
276 printf("Checksum mismatch!\n");
277 return -1;
278 }
279
280 file = fopen(oname, "wb");
281 if (!file) {
282 perror(oname);
283 return -3;
284 }
285
286 len = fwrite(outbuf+0x1030, 1, length-0x1030, file);
287 if(len < (size_t)length-0x1030) {
288 perror(oname);
289 return -4;
290 }
291
292 fclose(file);
293 return 0;
294}