reios/hleboot: support cdroms, descramble, slightly smarter bootfile search

core/reios/descrambl.cpp

@@ -0,0 +1,103 @@
+/*
+	Based on work of Marcus Comstedt
+	http://mc.pp.se, http://mc.pp.se/dc/sw.html, http://mc.pp.se/dc/files/scramble.c
+	License: Gotta verify
+
+	Adapted by Stefanos Kornilios Mitsis Poiitidis (skmp) for reicast
+*/
+
+#include "descrambl.h"
+#include <algorithm>
+
+#define MAXCHUNK (2048*1024)
+
+static unsigned int seed;
+
+void my_srand(unsigned int n)
+{
+	seed = n & 0xffff;
+}
+
+unsigned int my_rand()
+{
+	seed = (seed * 2109 + 9273) & 0x7fff;
+	return (seed + 0xc000) & 0xffff;
+}
+
+/*
+void load(FILE *fh, unsigned char *ptr, unsigned long sz)
+{
+	if (fread(ptr, 1, sz, fh) != sz)
+	{
+		fprintf(stderr, "Read error!\n");
+		exit(1);
+	}
+}
+*/
+
+void load_chunk(u8* &src, unsigned char *ptr, unsigned long sz)
+{
+	verify(sz < MAXCHUNK);
+
+	static int idx[MAXCHUNK / 32];
+
+	int i;
+
+	/* Convert chunk size to number of slices */
+	sz /= 32;
+
+	/* Initialize index table with unity,
+	so that each slice gets loaded exactly once */
+	for (i = 0; i < sz; i++)
+		idx[i] = i;
+
+	for (i = sz - 1; i >= 0; --i)
+	{
+		/* Select a replacement index */
+		int x = (my_rand() * i) >> 16;
+
+		/* Swap */
+		swap(idx[i], idx[x]);
+
+		/*
+			int tmp = idx[i];
+			idx[i] = idx[x];
+			idx[x] = tmp;
+		*/
+
+		/* Load resulting slice */
+		//load(fh, ptr + 32 * idx[i], 32);
+		memcpy(ptr + 32 * idx[i], src, 32);
+		src += 32;
+	}
+}
+
+void descrambl_buffer(u8* src, unsigned char *dst, unsigned long filesz)
+{
+	unsigned long chunksz;
+
+	my_srand(filesz);
+
+	/* Descramble 2 meg blocks for as long as possible, then
+	gradually reduce the window down to 32 bytes (1 slice) */
+	for (chunksz = MAXCHUNK; chunksz >= 32; chunksz >>= 1)
+		while (filesz >= chunksz)
+		{
+			load_chunk(src, dst, chunksz);
+			filesz -= chunksz;
+			dst += chunksz;
+		}
+
+	/* Load final incomplete slice */
+	if (filesz)
+		memcpy(dst, src, filesz);
+}
+
+void descrambl_file(u32 FAD, u32 file_size, u8* dst) {
+	u8* temp_file = new u8[file_size + 2048];
+	libGDR_ReadSector(temp_file, FAD, file_size / 2048, 2048);
+
+	descrambl_buffer(temp_file, dst, file_size);
+
+	delete[] temp_file;
+}

core/reios/descrambl.h

@@ -0,0 +1,3 @@
+#include "types.h"
+
+void descrambl_file(u32 FAD, u32 file_size, u8* dst);

core/reios/reios.cpp

@@ -10,6 +10,7 @@
 #include "reios.h"
 
 #include "gdrom_hle.h"
+#include "descrambl.h"
 
 #include "hw/sh4/sh4_mem.h"
 
@@ -28,13 +29,28 @@
 
 u8* biosrom;
 u8* flashrom;
+u32 base_fad = 45150;
+bool descrambl = false;
 
 bool reios_locate_bootfile(const char* bootfile="1ST_READ.BIN") {
-	u8* temp = new u8[2048 * 1024];
+	u32 data_len = 2048 * 1024;
+	u8* temp = new u8[data_len];
 
-	libGDR_ReadSector(temp, 45150 + 16, 1024, 2048);
+	libGDR_ReadSector(temp, base_fad + 16, 1, 2048);
 
-	for (int i = 0; i < 2048 * 1023; i++) {
+	if (memcmp(temp, "\001CD001\001", 7) == 0) {
+		u32 lba = (u32&)temp[156 + 2]; //Root directory lba, should use the big endian one
+		u32 len = (u32&)temp[156 + 10]; //should use the big endian one
+		
+		data_len = ((len + 2047) / 2048) *2048;
+
+		libGDR_ReadSector(temp, 150 + lba, data_len/2048, 2048);
+	}
+	else {
+		libGDR_ReadSector(temp, base_fad + 16, data_len / 2048, 2048);
+	}
+
+	for (int i = 0; i < (data_len-20); i++) {
 		if (memcmp(temp+i, bootfile, strlen(bootfile)) == 0){
 			printf("Found %s at %06X\n", bootfile, i);
 			
@@ -45,7 +61,10 @@ bool reios_locate_bootfile(const char* bootfile="1ST_READ.BIN") {
 			u32 lba = (u32&)temp[i - 33 +  2]; //should use the big endian one, but i'm lazy
 			u32 len = (u32&)temp[i - 33 + 10]; //should use the big endian one, but i'm lazy
 
-			libGDR_ReadSector(GetMemPtr(0x8c010000, 0), lba + 150, (len + 2047) / 2048, 2048);
+			if (descrambl)
+				descrambl_file(lba + 150, len, GetMemPtr(0x8c010000, 0));
+			else
+				libGDR_ReadSector(GetMemPtr(0x8c010000, 0), lba + 150, (len + 2047) / 2048, 2048);
 
 			delete[] temp;
 			return true;
@@ -58,7 +77,20 @@ bool reios_locate_bootfile(const char* bootfile="1ST_READ.BIN") {
 
 char reios_bootfile[32];
 const char* reios_locate_ip() {
-	libGDR_ReadSector(GetMemPtr(0x8c008000, 0), 45150, 16, 2048);
+
+	if (libGDR_GetDiscType() == GdRom) {
+		base_fad = 45150;
+		descrambl = false;
+	}
+	else {
+		u8 ses[6];
+		libGDR_GetSessionInfo(ses, 0);
+		libGDR_GetSessionInfo(ses, ses[2]);
+		base_fad = (ses[3] << 16) | (ses[4] << 8) | (ses[5] << 0);
+		descrambl = true;
+	}
+
+	libGDR_ReadSector(GetMemPtr(0x8c008000, 0), base_fad, 16, 2048);
 	
 	memset(reios_bootfile, 0, sizeof(reios_bootfile));
 	memcpy(reios_bootfile, GetMemPtr(0x8c008060, 0), 16);
@@ -316,7 +348,7 @@ void reios_boot() {
 	WriteMem32(0x80800000, 0xEAFFFFFE);
 
 	const char* bootfile = reios_locate_ip();
-	if (!reios_locate_bootfile(bootfile))
+	if (!bootfile || !reios_locate_bootfile(bootfile))
 		msgboxf("Failed to locate bootfile", MBX_ICONERROR);
 }
 

shell/reicast.vcxproj

@@ -157,6 +157,7 @@
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Fast|Win32'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Fast|x64'">true</ExcludedFromBuild>
     </ClCompile>
+    <ClCompile Include="..\core\reios\descrambl.cpp" />
     <ClCompile Include="..\core\reios\gdrom_hle.cpp" />
     <ClCompile Include="..\core\reios\reios.cpp" />
     <ClCompile Include="..\core\rend\d3d11\d3d11.cpp" />
@@ -288,6 +289,7 @@
     <ClInclude Include="..\core\oslib\audiostream_rif.h" />
     <ClInclude Include="..\core\oslib\oslib.h" />
     <ClInclude Include="..\core\profiler\profiler.h" />
+    <ClInclude Include="..\core\reios\descrambl.h" />
     <ClInclude Include="..\core\reios\gdrom_hle.h" />
     <ClInclude Include="..\core\reios\reios.h" />
     <ClInclude Include="..\core\rend\gles\gles.h" />

shell/reicast.vcxproj.filters

@@ -405,6 +405,9 @@
     <ClCompile Include="..\core\reios\gdrom_hle.cpp">
       <Filter>reios</Filter>
     </ClCompile>
+    <ClCompile Include="..\core\reios\descrambl.cpp">
+      <Filter>reios</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <Filter Include="hw">
@@ -883,6 +886,9 @@
     <ClInclude Include="..\core\reios\gdrom_hle.h">
       <Filter>reios</Filter>
     </ClInclude>
+    <ClInclude Include="..\core\reios\descrambl.h">
+      <Filter>reios</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <None Include="..\core\deps\zlib\Makefile">