X-Git-Url: https://git.siccegge.de//index.cgi?p=frida%2Ffrida.git;a=blobdiff_plain;f=src%2Fdisassembler%2Fllvm%2FLLVMDisassembler.cxx;h=76b313de3bf996d0d355bc69e9b004c47d476efb;hp=6e76c91bc27c8121f7088460401ae3c20d4faf47;hb=9244195b13b1673757b4bc77d6306e7b2f21244a;hpb=f66c54319d23de4c4905ad11a8f552917d2dfba9

diff --git a/src/disassembler/llvm/LLVMDisassembler.cxx b/src/disassembler/llvm/LLVMDisassembler.cxx
index 6e76c91..76b313d 100644
--- a/src/disassembler/llvm/LLVMDisassembler.cxx
+++ b/src/disassembler/llvm/LLVMDisassembler.cxx
@@ -121,14 +121,12 @@ LLVMDisassembler::~LLVMDisassembler() {
                   });
 }
 
-/*
- * TODO: If we jump into some Basic Block we need to split it there into two
- */
 void LLVMDisassembler::disassemble() {
     std::stack<LLVMFunction*> remaining_functions;
     std::stack<LLVMBasicBlock*> remaining_blocks;
     SectionRef text_section = sections[".text"];
 
+	// Assume all function symbols actually start a real function
     for (auto x = symbols.begin(); x != symbols.end(); ++x) {
         uint64_t result;
         bool contains;
@@ -160,9 +158,6 @@ void LLVMDisassembler::disassemble() {
 
         LOG4CXX_DEBUG(logger, "Handling function " << current_function->getName());
 
-        // if ("_start" != current_function->getName())
-        //  continue;
-
         LLVMBasicBlock * block = new LLVMBasicBlock(current_function->getStartAddress(), this);
         remaining_blocks.push(block);
         blocks.insert(std::make_pair(block->getStartAddress(), block));
@@ -185,19 +180,6 @@ void LLVMDisassembler::disassemble() {
                 if(llvm::MCDisassembler::Success ==
                    DisAsm->getInstruction(inst, inst_size, ref, current_address, nulls(), nulls())) {
 
-                    uint8_t bytes[inst_size+2];
-                    ref.readBytes(current_address, inst_size, bytes);
-                    s << '\t';
-                    for(uint8_t* cur = bytes; cur < bytes + inst_size; ++cur) {
-                        s.write_hex(*cur);
-                        s << ' ';
-                    }
-                    s << '\t';
-
-                    IP->printInst(&inst, s, "");
-
-                    LOG4CXX_DEBUG(logger, std::hex << current_address + base_address << s.str());
-
                     uint64_t jmptarget;
                     if (MIA->evaluateBranch(inst, current_address, inst_size, jmptarget)) {
                         jmptarget += base_address;
@@ -211,18 +193,18 @@ void LLVMDisassembler::disassemble() {
                                     remaining_functions.push(fun);
                                 }
                             } else {
+								current_block->setNextBlock(0, jmptarget);
                                 if (blocks.find(jmptarget) == blocks.end()) {
                                     LLVMBasicBlock * block = new LLVMBasicBlock(jmptarget, this);
                                     blocks.insert(std::make_pair(block->getStartAddress(), block));
-                                    current_block->setNextBlock(0, block->getStartAddress());
                                     remaining_blocks.push(block);
                                 }
                                 if (MIA->isConditionalBranch(inst)) {
                                     jmptarget = base_address + current_address + inst_size;
+									current_block->setNextBlock(1, jmptarget);
                                     if (blocks.find(jmptarget) == blocks.end()) {
                                         LLVMBasicBlock * block = new LLVMBasicBlock(jmptarget, this);
                                         blocks.insert(std::make_pair(block->getStartAddress(), block));
-                                        current_block->setNextBlock(1, block->getStartAddress());
                                         remaining_blocks.push(block);
                                     }
                                 }
@@ -245,6 +227,42 @@ void LLVMDisassembler::disassemble() {
         }
         LOG4CXX_DEBUG(logger, "Finished function " << current_function->getName());
     }
+
+	// Split blocks where jumps are going inside the block
+	for (auto it = blocks.begin(); it != blocks.end(); ++it) {
+		LLVMBasicBlock * current_block = it->second;
+		uint64_t inst_size;
+		uint64_t base_address;
+		text_section.getAddress(base_address);
+		uint64_t current_address = current_block->getStartAddress() - base_address;
+		while(current_block->getEndAddress() - base_address > current_address) {
+			MCInst inst;
+			std::string buf;
+			llvm::raw_string_ostream s(buf);
+
+			if(llvm::MCDisassembler::Success ==
+			   DisAsm->getInstruction(inst, inst_size, ref, current_address, nulls(), nulls())) {
+				auto other = blocks.find(current_address + inst_size + base_address);
+
+				if (other != blocks.end()) {
+					uint64_t endaddress = current_address + inst_size + base_address;
+					if (endaddress != current_block->getEndAddress()) {
+						LOG4CXX_DEBUG(logger, "Shortening block starting at "
+									  << std::hex
+									  << current_block->getStartAddress()
+									  << " now ending at "
+									  << other->first);
+						current_block->setEndAddress(endaddress);
+						current_block->setNextBlock(0, other->first);
+						current_block->setNextBlock(1, 0);
+					}
+				}
+			} else {
+				inst_size = 1;
+			}
+			current_address += inst_size;
+		}
+	}
 }
 
 void LLVMDisassembler::readSymbols() {
@@ -283,7 +301,8 @@ void LLVMDisassembler::forEachFunction(std::function<void (uint64_t, Function*)>
                   });
 }
 
-void LLVMDisassembler::printEachInstruction(uint64_t start, uint64_t end, std::function<void (const std::string&)> fun) {
+void LLVMDisassembler::printEachInstruction(uint64_t start, uint64_t end,
+											std::function<void (uint8_t*, size_t, const std::string&)> fun) {
     SectionRef text_section = sections[".text"];
     uint64_t base_address;
     text_section.getAddress(base_address);
@@ -304,16 +323,19 @@ void LLVMDisassembler::printEachInstruction(uint64_t start, uint64_t end, std::f
 
             uint8_t bytes[inst_size+2];
             ref.readBytes(current_address, inst_size, bytes);
-            for(uint8_t* cur = bytes; cur < bytes + inst_size; ++cur) {
-                s.write_hex(*cur);
-                s << ' ';
-            }
-            s << '\t';
 
-            IP->printInst(&inst, s, "");
-			fun(s.str());
+			uint64_t jmptarget;
+			if (MIA->evaluateBranch(inst, current_address, inst_size, jmptarget)) {
+				std::stringstream stream;
+				stream << std::hex << (base_address + jmptarget);
+				IP->printInst(&inst, s, stream.str());
+			} else
+				IP->printInst(&inst, s, "");
+
+			fun(bytes, inst_size, s.str());
         } else {
-			fun("Invalid Byte");
+			LOG4CXX_WARN(logger, "Invalid byte at" << std::hex << current_address + base_address);
+			fun(NULL, 0, "Invalid Byte");
 			inst_size = 1;
 		}