IL2CPP: Refactor reconstructor for single data read with multiple passes

This commit is contained in:
Katy Coe
2020-12-05 22:04:24 +01:00
parent 29fd34dc3a
commit f3bde0173e

View File

@@ -221,11 +221,10 @@ namespace Il2CppInspector
if (metadata == null)
return;
(ulong ptr, int count) types = (0, 0);
// Read in all the required data once since we'll be using nested loops
var metaPtrData = new List<(ulong, int, ulong[], ulong[], int, int, int)>();
// Determine what each pointer is
for (var i = 0; i < metaPtrsOrdered.Count; i++) {
// Pointers in this list
var ptrs = Image.ReadMappedArray<ulong>(metaPtrsOrdered[i], metaCountLimits[i]);
@@ -240,53 +239,91 @@ namespace Il2CppInspector
// First set of pointers that can be mapped into a data section in the image
var ptrsMappableData = ptrs.Take(foundMappableCount)
.TakeWhile(p => dataSections.Any(s => Image.MapVATR(p) >= s.ImageStart && Image.MapVATR(p) <= s.ImageEnd))
.ToList();
.TakeWhile(p => dataSections.Any(s => Image.MapVATR(p) >= s.ImageStart && Image.MapVATR(p) <= s.ImageEnd))
.ToArray();
var foundMappableDataCount = ptrsMappableData.Count;
var foundMappableDataCount = ptrsMappableData.Length;
// Test for Il2CppType**
// We don't ever expect there to be less than 0x1000 types
if (foundMappableDataCount >= 0x1000) {
// This statement is quite slow. We could speed it up with a two-stage approach
var testTypes = Image.ReadMappedObjectPointerArray<Il2CppType>(metaPtrsOrdered[i], foundMappableDataCount);
metaPtrData.Add((metaPtrsOrdered[i], metaCountLimits[i], ptrs, ptrsMappableData, foundCount, foundMappableCount, foundMappableDataCount));
}
var foundTypes = 0;
foreach (var testType in testTypes) {
// TODO: v27 will fail this because of the bit shifting in Il2CppType.bits
if (testType.num_mods != 0)
break;
if (!Enum.IsDefined(typeof(Il2CppTypeEnum), testType.type))
break;
if (testType.type == Il2CppTypeEnum.IL2CPP_TYPE_END)
break;
// Items we need to search for
var types = (ptr: 0ul, count: -1);
var genericInsts = (ptr: 0ul, count: -1);
// Test datapoint
if (testType.type switch {
var t when (t is Il2CppTypeEnum.IL2CPP_TYPE_VALUETYPE || t is Il2CppTypeEnum.IL2CPP_TYPE_CLASS)
&& testType.datapoint >= (ulong) metadata.Types.Length => false,
// Determine what each pointer is
// We need to do this in a certain order because validating some items relies on earlier items
while (metaPtrData.Any()) {
var t when (t is Il2CppTypeEnum.IL2CPP_TYPE_VAR || t is Il2CppTypeEnum.IL2CPP_TYPE_MVAR)
&& testType.datapoint >= (ulong) metadata.GenericParameters.Length => false,
var foundTarget = 0ul;
var t when (t is Il2CppTypeEnum.IL2CPP_TYPE_PTR || t is Il2CppTypeEnum.IL2CPP_TYPE_SZARRAY)
&& !ptrsMappableData.Contains(testType.datapoint) => false,
// We loop repeatedly through every set of data looking for our next target item,
// remove the matching set from the list and then repeat the outer while loop
// until there is nothing left to find
foreach (var (ptr, count, ptrs, ptrsMappableData, foundCount, foundMappableCount, foundMappableDataCount) in metaPtrData) {
// Untested cases, we could add more here (IL2CPP_TYPE_ARRAY, IL2CPP_TYPE_GENERICINST)
_ => true
})
foundTypes++;
else
break;
}
if (foundTypes >= 0x1000) {
types = (metaPtrsOrdered[i], foundTypes);
// Test for Il2CppType**
// ---------------------
if (types.ptr == 0) {
// We don't ever expect there to be less than 0x1000 types
if (foundMappableDataCount >= 0x1000) {
// This statement is quite slow. We could speed it up with a two-stage approach
var testTypes = Image.ReadMappedObjectPointerArray<Il2CppType>(ptr, foundMappableDataCount);
var foundTypes = 0;
foreach (var testType in testTypes) {
// TODO: v27 will fail this because of the bit shifting in Il2CppType.bits
if (testType.num_mods != 0)
break;
if (!Enum.IsDefined(typeof(Il2CppTypeEnum), testType.type))
break;
if (testType.type == Il2CppTypeEnum.IL2CPP_TYPE_END)
break;
// Test datapoint
if (testType.type switch {
var t when (t is Il2CppTypeEnum.IL2CPP_TYPE_VALUETYPE || t is Il2CppTypeEnum.IL2CPP_TYPE_CLASS)
&& testType.datapoint >= (ulong) metadata.Types.Length => false,
var t when (t is Il2CppTypeEnum.IL2CPP_TYPE_VAR || t is Il2CppTypeEnum.IL2CPP_TYPE_MVAR)
&& testType.datapoint >= (ulong) metadata.GenericParameters.Length => false,
var t when (t is Il2CppTypeEnum.IL2CPP_TYPE_PTR || t is Il2CppTypeEnum.IL2CPP_TYPE_SZARRAY)
&& !ptrsMappableData.Contains(testType.datapoint) => false,
// Untested cases, we could add more here (IL2CPP_TYPE_ARRAY, IL2CPP_TYPE_GENERICINST)
_ => true
})
foundTypes++;
else
break;
}
if (foundTypes >= 0x1000) {
types = (ptr, foundTypes);
foundTarget = ptr;
break;
}
}
}
// Test for Il2CppGenericInst**
// ----------------------------
}
// Successfully found the item we were looking for; remove it from the list
if (foundTarget != 0ul)
metaPtrData = metaPtrData.Where(m => foundTarget != m.Item1).ToList();
// We didn't find anything - break to avoid an infinite loop
else
break;
}
#region Debugging validation checks
#if DEBUG
#if DEBUG
// Used on non-obfuscated binaries during development to confirm the output is correct
if (types.ptr != MetadataRegistration.ptypes)
throw new Exception("Il2CppType** incorrect");
@@ -299,6 +336,8 @@ namespace Il2CppInspector
// Perform substitution
MetadataRegistration.ptypes = types.ptr;
MetadataRegistration.typesCount = types.count;
MetadataRegistration.genericInsts = genericInsts.ptr;
MetadataRegistration.genericInstsCount = genericInsts.count;
// Force MetadataRegistration to pass validation in Il2CppBinary.Configure()
MetadataRegistration.typeDefinitionsSizesCount = 0;