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Code Issues Releases Wiki Activity

GP-587: Assembling bytes into a side buffer, then patching all at once.

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This commit is contained in:
Dan 2021-02-09 08:03:40 -05:00
parent ed3cc10344
commit 98331405b8
2 changed files with 49 additions and 28 deletions
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36
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/assembler/Assembler.java
View file

@ -21,8 +21,8 @@ import ghidra.app.plugin.assembler.sleigh.parse.AssemblyParseResult;
import ghidra.app.plugin.assembler.sleigh.sem.*;
import ghidra.program.model.address.Address;
import ghidra.program.model.address.AddressOverflowException;
import ghidra.program.model.lang.InstructionBlock;
import ghidra.program.model.listing.Instruction;
import ghidra.program.model.listing.InstructionIterator;
import ghidra.program.model.mem.MemoryAccessException;
/**
@ -36,8 +36,8 @@ public interface Assembler {
* Assemble a sequence of instructions and place them at the given address.
*
* This method is only valid if the assembler is bound to a program. An instance may optionally
* implement this method without a program binding. In that case, the returned instruction
* block will refer to pseudo instructions.
* implement this method without a program binding. In that case, the returned instruction block
* will refer to pseudo instructions.
*
* NOTE: There must be an active transaction on the bound program for this method to succeed.
*
@ -49,7 +49,8 @@ public interface Assembler {
* @throws MemoryAccessException there is an issue writing the result to program memory
* @throws AddressOverflowException the resulting block is beyond the valid address range
*/
public InstructionBlock assemble(Address at, String... listing) throws AssemblySyntaxException,
public InstructionIterator assemble(Address at, String... listing)
throws AssemblySyntaxException,
AssemblySemanticException, MemoryAccessException, AddressOverflowException;
/**
@ -96,6 +97,7 @@ public interface Assembler {
* Because all parse paths are attempted, it's possible to get many mixed results. For example,
* The input line may be a valid instruction; however, there may be suggestions to continue the
* line toward another valid instruction.
*
* @param line the line (or partial line) to parse
* @return the results of parsing
*/
@ -108,8 +110,9 @@ public interface Assembler {
* semantic error. Because all resolutions are attempted, it's possible to get many mixed
* results.
*
* NOTE: The resolved instructions are given as masks and values. Where the mask does not
* cover, you can choose any value.
* NOTE: The resolved instructions are given as masks and values. Where the mask does not cover,
* you can choose any value.
*
* @param parse a parse result giving a valid tree
* @param at the location of the start of the instruction
* @param ctx the context register value at the start of the instruction
@ -125,8 +128,9 @@ public interface Assembler {
* semantic error. Because all resolutions are attempted, it's possible to get many mixed
* results.
*
* NOTE: The resolved instructions are given as masks and values. Where the mask does not
* cover, you can choose any value.
* NOTE: The resolved instructions are given as masks and values. Where the mask does not cover,
* you can choose any value.
*
* @param parse a parse result giving a valid tree
* @param at the location of the start of the instruction
* @return the results of semantic resolution
@ -138,6 +142,7 @@ public interface Assembler {
*
* This method works like {@link #resolveLine(Address, String, AssemblyPatternBlock)}, except
* that it derives the context using {@link #getContextAt(Address)}.
*
* @param at the location of the start of the instruction
* @param line the textual assembly code
* @return the collection of semantic resolution results
@ -152,6 +157,7 @@ public interface Assembler {
* This method works like {@link #assembleLine(Address, String, AssemblyPatternBlock)}, except
* that it returns all possible resolutions for the parse trees that pass the
* {@link AssemblySelector}.
*
* @param at the location of the start of the instruction
* @param line the textual assembly code
* @param ctx the context register value at the start of the instruction
@ -164,8 +170,9 @@ public interface Assembler {
/**
* Place a resolved (and fully-masked) instruction into the bound program.
*
* This method is not valid without a program binding. Also, this method must be called during
* a program database transaction.
* This method is not valid without a program binding. Also, this method must be called during a
* program database transaction.
*
* @param res the resolved and fully-masked instruction
* @param at the location of the start of the instruction
* @return the new {@link Instruction} code unit
@ -177,20 +184,23 @@ public interface Assembler {
/**
* Place an instruction into the bound program.
*
* This method is not valid without a program binding. Also, this method must be called during
* a program database transaction.
* This method is not valid without a program binding. Also, this method must be called during a
* program database transaction.
*
* @param insbytes the instruction data
* @param at the location of the start of the instruction
* @return the new {@link Instruction} code unit
* @throws MemoryAccessException there is an issue writing the result to program memory
*/
public Instruction patchProgram(byte[] insbytes, Address at) throws MemoryAccessException;
public InstructionIterator patchProgram(byte[] insbytes, Address at)
throws MemoryAccessException;
/**
* Get the context at a given address
*
* If there is a program binding, this will extract the actual context at the given address.
* Otherwise, it will obtain the default context at the given address for the language.
*
* @param addr the address
* @return the context
*/

37
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/assembler/sleigh/SleighAssembler.java
View file

@ -15,6 +15,8 @@
*/
package ghidra.app.plugin.assembler.sleigh;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.*;
import ghidra.app.plugin.assembler.*;
@ -25,7 +27,8 @@ import ghidra.app.plugin.processors.sleigh.SleighLanguage;
import ghidra.program.disassemble.Disassembler;
import ghidra.program.disassemble.DisassemblerMessageListener;
import ghidra.program.model.address.*;
import ghidra.program.model.lang.*;
import ghidra.program.model.lang.Register;
import ghidra.program.model.lang.RegisterValue;
import ghidra.program.model.listing.*;
import ghidra.program.model.mem.Memory;
import ghidra.program.model.mem.MemoryAccessException;
@ -98,22 +101,26 @@ public class SleighAssembler implements Assembler {
if (!res.getInstruction().isFullMask()) {
throw new AssemblySelectionError("Selected instruction must have a full mask.");
}
return patchProgram(res.getInstruction().getVals(), at);
return patchProgram(res.getInstruction().getVals(), at).next();
}
@Override
public Instruction patchProgram(byte[] insbytes, Address at) throws MemoryAccessException {
listing.clearCodeUnits(at, at.add(insbytes.length - 1), false);
public InstructionIterator patchProgram(byte[] insbytes, Address at)
throws MemoryAccessException {
Address end = at.add(insbytes.length - 1);
listing.clearCodeUnits(at, end, false);
memory.setBytes(at, insbytes);
dis.disassemble(at, new AddressSet(at));
return listing.getInstructionAt(at);
List<Instruction> result = new ArrayList<>();
return listing.getInstructions(new AddressSet(at, end), true);
}
@Override
public InstructionBlock assemble(Address at, String... assembly) throws AssemblySyntaxException,
AssemblySemanticException, MemoryAccessException, AddressOverflowException {
InstructionBlock block = new InstructionBlock(at);
public InstructionIterator assemble(Address at, String... assembly)
throws AssemblySyntaxException, AssemblySemanticException, MemoryAccessException,
AddressOverflowException {
Address start = at;
ByteArrayOutputStream buf = new ByteArrayOutputStream();
for (String part : assembly) {
for (String line : part.split("\n")) {
RegisterValue rv = program.getProgramContext().getDisassemblyContext(at);
@ -124,13 +131,16 @@ public class SleighAssembler implements Assembler {
if (insbytes == null) {
return null;
}
Instruction ins = patchProgram(insbytes, at);
block.addInstruction(ins);
try {
buf.write(insbytes);
}
catch (IOException e) {
throw new AssertionError(e);
}
at = at.addNoWrap(insbytes.length);
}
}
return block;
return patchProgram(buf.toByteArray(), start);
}
@Override
@ -221,6 +231,7 @@ public class SleighAssembler implements Assembler {
/**
* A convenience to obtain a map of program labels strings to long values
*
* @return the map
*
* {@literal TODO Use a Map<String, Address> instead so that, if possible, symbol values can be checked}