スクランブルのROMを解析してみた　その１

ここらへんを参考にして、オレたちゲーセン族のROMを解析してみる。

http://d.hatena.ne.jp/eth0jp/20110603/1307033578

出版社/メーカー: ハムスター
発売日: 2005/07/21
メディア: Video Game
購入: 3人クリック: 43回
この商品を含むブログ (6件) を見る

http://mamedev.org/source/src/mame/drivers/galdrvr.c.html

 ROM_START( scramble )
 ROM_REGION( 0x10000, "maincpu", 0 )
 ROM_LOAD( "s1.2d",        0x0000, 0x0800, CRC(ea35ccaa) SHA1(1dcb375987fe21e0483c27d485c405de53848d61) )
 ROM_LOAD( "s2.2e",        0x0800, 0x0800, CRC(e7bba1b3) SHA1(240877576045fddcc9ff01d97dc78139454ac4f1) )
 ROM_LOAD( "s3.2f",        0x1000, 0x0800, CRC(12d7fc3e) SHA1(a84d191c7be8700f630a83ddad798be9e83b5d55) )
 ROM_LOAD( "s4.2h",        0x1800, 0x0800, CRC(b59360eb) SHA1(5d155808c19dcf2e14aa8e29c0ee41a6d3d3c43a) )
 ROM_LOAD( "s5.2j",        0x2000, 0x0800, CRC(4919a91c) SHA1(9cb5861c61e4783e5fbaa3869d51195f127b1129) )
 ROM_LOAD( "s6.2l",        0x2800, 0x0800, CRC(26a4547b) SHA1(67c0fa81729370631647b5d78bb5a61433facd7f) )
 ROM_LOAD( "s7.2m",        0x3000, 0x0800, CRC(0bb49470) SHA1(05a6fe3010c2136284ca76352dac147797c79778) )
 ROM_LOAD( "s8.2p",        0x3800, 0x0800, CRC(6a5740e5) SHA1(e3b09141cee26857d626412e9d1a0e759469b97a) )
 
 ROM_REGION( 0x10000, "audiocpu", 0 )
 ROM_LOAD( "ot1.5c",       0x0000, 0x0800, CRC(bcd297f0) SHA1(8ed78487d76fd0a917ab7b258937a46e2cd9800c) )
 ROM_LOAD( "ot2.5d",       0x0800, 0x0800, CRC(de7912da) SHA1(8558b4eff5d7e63029b325edef9914feda5834c3) )
 ROM_LOAD( "ot3.5e",       0x1000, 0x0800, CRC(ba2fa933) SHA1(1f976d8595706730e29f93027e7ab4620075c078) )
 
 ROM_REGION( 0x1000, "gfx1", 0 )
 ROM_LOAD( "c2.5f",        0x0000, 0x0800, CRC(4708845b) SHA1(a8b1ad19a95a9d35050a2ab7194cc96fc5afcdc9) )
 ROM_LOAD( "c1.5h",        0x0800, 0x0800, CRC(11fd2887) SHA1(69844e48bb4d372cac7ae83c953df573c7ecbb7f) )
 
 ROM_REGION( 0x0020, "proms", 0 )
 ROM_LOAD( "c01s.6e",      0x0000, 0x0020, CRC(4e3caeab) SHA1(a25083c3e36d28afdefe4af6e6d4f3155e303625) )
 ROM_END

結果7個のROMはCRC32が一致したので、残り7個のアドレスを推測してみる。

>crc SLPM_626.26 ea35ccaa 800
>crc SLPM_626.26 e7bba1b3 800
>crc SLPM_626.26 12d7fc3e 800
>crc SLPM_626.26 b59360eb 800
>crc SLPM_626.26 4919a91c 800
>crc SLPM_626.26 26a4547b 800
>crc SLPM_626.26 0bb49470 800
crc32=0bb49470,size=0800
crc32=0bb49470,addr=5a43d-5ac3c(s7.2m)
>crc SLPM_626.26 6a5740e5 800
>crc SLPM_626.26 bcd297f0 800
crc32=bcd297f0,size=0800
crc32=bcd297f0,addr=674d0-67ccf(ot1.5c)
>crc SLPM_626.26 de7912da 800
crc32=de7912da,size=0800
crc32=de7912da,addr=67cd0-684cf(ot2.5d)
>crc SLPM_626.26 ba2fa933 800
crc32=ba2fa933,size=0800
crc32=ba2fa933,addr=684d0-68ccf(ot3.5e)
>crc SLPM_626.26 11fd2887 800
crc32=11fd2887,size=0800
crc32=11fd2887,addr=774d0-77ccf(c1.5h)
>crc SLPM_626.26 4708845b 800
crc32=4708845b,size=0800
crc32=4708845b,addr=77cd0-784cf(c2.5f)
>crc SLPM_626.26 4e3caeab 20
crc32=4e3caeab,size=0020
crc32=4e3caeab,addr=784d0-784ef(c01s.6e)

おそらく残り7個のアドレスはこうではないかな？

crc32=xxxxxxxx,addr=56c3d-5743c -7
crc32=xxxxxxxx,addr=5743d-57c3c -6(s1.2d)
crc32=xxxxxxxx,addr=57c3d-5843c -5(s2.2e)
crc32=xxxxxxxx,addr=5843d-58c3c -4(s3.2f)
crc32=xxxxxxxx,addr=58c3d-5943c -3(s4.2h)
crc32=xxxxxxxx,addr=5943d-59c3c -2(s5.2j)
crc32=xxxxxxxx,addr=59c3d-5a43c -1(s6.2l)
crc32=0bb49470,addr=5a43d-5ac3c OK(s7.2m)
crc32=xxxxxxxx,addr=5ac3d-5b43c +1(s8.2p)
crc32=xxxxxxxx,addr=5b43d-5bc3c +2
crc32=xxxxxxxx,addr=5bc3d-5c43c +3
crc32=xxxxxxxx,addr=5c43d-5cc3c +4
crc32=xxxxxxxx,addr=5cc3d-5d43c +5
crc32=xxxxxxxx,addr=5d43d-5dc3c +6
crc32=xxxxxxxx,addr=5dc3d-5e43c +7

>cut SLPM_626.26 5743d 800
>cut SLPM_626.26 57c3d 800
>cut SLPM_626.26 5843d 800
>cut SLPM_626.26 58c3d 800
>cut SLPM_626.26 5943d 800
>cut SLPM_626.26 59c3d 800
>cut SLPM_626.26 5a43d 800
>cut SLPM_626.26 5ac3d 800

まあ結果、MAMEで動かなかったのでPS2で遊びます。

crc.c

#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <sys/stat.h>

static const unsigned int crc32tab[256] = { 
	0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
	0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
	0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
	0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
	0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
	0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
	0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
	0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
	0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
	0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
	0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
	0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
	0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
	0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
	0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
	0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
	0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
	0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
	0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
	0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
	0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
	0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
	0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
	0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
	0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
	0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
	0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
	0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
	0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
	0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
	0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
	0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
	0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
	0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
	0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
	0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
	0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
	0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
	0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
	0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
	0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
	0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
	0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
	0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
	0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
	0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
	0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
	0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
	0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
	0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
	0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
	0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
	0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
	0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
	0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
	0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
	0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
	0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
	0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
	0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
	0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
	0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
	0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
	0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
};

unsigned int crc32(char *p, int len)
{
	unsigned int crcinit = 0;
	unsigned int crc = 0;

	crc = crcinit ^ 0xFFFFFFFF;
	for (; len--; p++) {
		crc = ((crc >> 8) & 0x00FFFFFF) ^ crc32tab[(crc ^ (*p)) & 0xFF];
	}
	return crc ^ 0xFFFFFFFF;
}

int main(int ac, char **av)
{
	struct stat stbuf;
	unsigned int crc;
	unsigned int c;
	unsigned char *p;
	int size, len, i;
	FILE *fp;
	if (ac != 4) return -1;
	if (-1==stat(av[1], &stbuf)) return -1;
	if (NULL==(fp=fopen(av[1], "rb"))) return -1;
	size=stbuf.st_size;
	sscanf(av[2], "%08x", &crc);
	sscanf(av[3], "%04x", &len);
	printf("crc32=%08x,size=%04x\n", crc, len);
	p=malloc(size);
	fread(p, 1, size, fp);
	fclose(fp);
	for (i=0; i <= size-len; i++) {
		c=crc32(p+i, len);
		if (c == crc)
			goto found;
	}
	return -1;
found:
	if (NULL==(fp=fopen(av[2], "wb"))) return -1;
	fwrite(p+i, 1, len, fp);
	fclose(fp);
	printf("crc32=%08x,addr=%04x-%04x\n", c, i, i+len-1);
	return 0;
}