Support for swift error messages

Muirey03 · May 27, 2020 · e961bc4 · e961bc4
1 parent d1a3a99
commit e961bc4
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Showing 4 changed files with 91 additions and 1 deletion.
diff --git a/cr4shedmach/TweakMach.xm b/cr4shedmach/TweakMach.xm
@@ -126,7 +126,39 @@
 		info->thread_num = threadNum;
 		info->thread_name = threadNames.count > threadNum ? threadNames[threadNum] : nil;
 		info->register_info = get_register_info(thread);
-
+
+		//get annotation:
+		NSString* libSwiftPath = nil;
+		mach_vm_address_t staticAnnotationAddr = findSymbolInTask(task, "_gCRAnnotations", @"libswiftCore.dylib", &libSwiftPath);
+		NSString* swiftErrorMessage = nil;
+		if (staticAnnotationAddr && libSwiftPath.length)
+		{
+			NSArray* images = CR4GetIvar<NSArray*>(self, "_binaryImages");
+			mach_vm_address_t annotationAddr = 0;
+			for (NSDictionary* img in images)
+			{
+				if ([img[@"ExecutablePath"] isEqualToString:libSwiftPath])
+				{
+					uint64_t start = [img[@"StartAddress"] unsignedLongLongValue];
+					annotationAddr = staticAnnotationAddr + start;
+					break;
+				}
+			}
+
+			if (annotationAddr)
+			{
+				mach_vm_address_t msgAddr = 0;
+				rread(task, annotationAddr + offsetof(crashreporter_annotations_t, message), &msgAddr, sizeof(mach_vm_address_t));
+				if (msgAddr)
+				{
+					swiftErrorMessage = [self _readStringAtTaskAddress:msgAddr immutableOnly:NO maxLength:0];
+					if ([swiftErrorMessage hasSuffix:@"\n"])
+						swiftErrorMessage = [swiftErrorMessage substringWithRange:NSMakeRange(0, swiftErrorMessage.length - 1)];
+				}
+			}
+		}
+		info->swiftErrorMessage = swiftErrorMessage;
+
 		//get unsymbolicated backtrace:
 		__block NSMutableArray* callStackSymbols = nil;
 		__block NSInteger i = 0;
@@ -224,6 +256,8 @@
 								info->exception_subtype,
 								info->exception_codes,
 								culprit];
+		if (info->swiftErrorMessage)
+			[logStr appendFormat:@"Swift Error Message: %@\n", info->swiftErrorMessage];
 		if (info->vm_info)
 			[logStr appendFormat:@"VM Protection: %s\n", info->vm_info];
 		if (terminationReason.length)

diff --git a/cr4shedmach/cr4shed_mach.h b/cr4shedmach/cr4shed_mach.h
@@ -6,6 +6,7 @@ struct exception_info
 	NSString* processName;
 	NSString* bundleID;
 	NSString* exception_type;
+	NSString* swiftErrorMessage;
 	const char* exception_subtype;
 	const char* vm_info;
 	uint64_t thread_num;
@@ -34,4 +35,5 @@ struct exception_info
 -(void)decodeBacktraceWithBlock:(void(^)(NSInteger, id))arg1;
 -(NSDictionary*)binaryImageDictionaryForAddress:(uint64_t)addr;
 -(void)generateCr4shedReport;
+-(NSString*)_readStringAtTaskAddress:(mach_vm_address_t)addr immutableOnly:(BOOL)imut maxLength:(NSUInteger)maxLen;
 @end
diff --git a/cr4shedmach/mach_utils.h b/cr4shedmach/mach_utils.h
@@ -21,6 +21,18 @@ struct register_info
 	uint64_t value;
 };
 
+struct crashreporter_annotations_t
+{
+	uint64_t version;
+	char* message;
+	uint64_t signature_string;
+	uint64_t backtrace;
+	char* message2;
+	uint64_t thread;
+	uint64_t dialog_mode;
+	uint64_t abort_cause;
+};
+
 NSString* mach_exception_string(exception_type_t exception, NSString* signalName);
 const char* mach_code_string(exception_type_t type, mach_exception_data_t codes, mach_msg_type_number_t codeCnt);
 char* mach_exception_codes_string(mach_exception_data_t codes, mach_msg_type_number_t codeCnt);
@@ -33,6 +45,7 @@ void freeThreadArray(thread_act_port_array_t threads, mach_msg_type_number_t thr
 BOOL createDir(NSString* path);
 void writeStringToFile(NSString* str, NSString* path);
 NSString* stringFromTime(time_t time, CR4DateFormat type);
+mach_vm_address_t findSymbolInTask(mach_port_t task, const char* symbolName, NSString* lastPathComponent, NSString** imageName);
 template <typename Type>
 static inline Type CR4GetIvar(id self, const char* name)
 {

diff --git a/cr4shedmach/mach_utils.mm b/cr4shedmach/mach_utils.mm
@@ -2,6 +2,7 @@
 @import Foundation;
 
 #import "mach_utils.h"
+#import "symbolication.h"
 #include <stdlib.h>
 #include <string.h>
 #include <MRYIPCCenter.h>
@@ -297,3 +298,43 @@ void writeStringToFile(NSString* str, NSString* path)
 	}
 	return str;
 }
+
+mach_vm_address_t findSymbolInTask(mach_port_t task, const char* symbolName, NSString* lastPathComponent, NSString** imageName)
+{
+	CSSymbolicatorRef symbolicator = CSSymbolicatorCreateWithTask(task);
+	if (CSIsNull(symbolicator))
+		return 0;
+
+	__block mach_vm_address_t addr = 0;
+	__block NSString* imagePath = nil;
+	CSSymbolicatorForeachSymbolAtTime(symbolicator, kCSNow, ^int(CSSymbolRef symbol){
+		if (!CSIsNull(symbol))
+		{
+			const char* name = CSSymbolGetMangledName(symbol);
+			if (name && symbolName)
+			{
+				if (strcmp(name, symbolName) == 0)
+				{
+					mach_vm_address_t symAddr = CSSymbolGetRange(symbol).location;
+					CSSymbolOwnerRef owner = CSSymbolGetSymbolOwner(symbol);
+					if (!CSIsNull(owner))
+					{
+						const char* c_path = CSSymbolOwnerGetPath(owner);
+						NSString* path = c_path ? @(c_path) : nil;
+						if ([path.lastPathComponent isEqualToString:lastPathComponent])
+						{
+							addr = symAddr - CSSymbolOwnerGetBaseAddress(owner);
+							imagePath = path;
+							return 0;
+						}
+					}
+				}
+			}
+		}
+		return 1;
+	});
+	CSRelease(symbolicator);
+	if (imageName)
+		*imageName = imagePath;
+	return addr;
+}