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Merged
merged 1 commit into from
Jul 28, 2023
Merged

Display the absolute address for relative jumps on x86 #54

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2 changes: 1 addition & 1 deletion fixtures/snapshots/asm_x86_64.txt
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Original file line number Diff line number Diff line change
@@ -1 +1 @@
{"startAddress":"0x17a20","size":"0x3d","arch":"x86_64","syntax":["Intel","C style"],"instructions":[[0,"jl $-0x64","if /* signed */ less(rflags) then jmp $-0x64"],[2,"add eax, dword [rax]","eax += [rax]"],[4,"mov edx, 0x38","edx = 0x38"],[9,"mov rcx, r15","rcx = r15"],[12,"call 0x39c6f","0x39c6f = call(0x39c6f)"],[17,"xor eax, eax","eax ^= eax"],[19,"jmp $+0x9a","jmp $+0x9a"],[24,"mov rbx, qword [r15]","rbx = [r15]"],[27,"cmp rbx, rax","rflags = flags(rbx - rax)"],[30,"jz $+0x35","if zero(rflags) then jmp $+0x35"],[32,"mov rdx, qword [r15 + 0x8]","rdx = [r15 + 0x8]"],[36,"mov qword [rdx], rbx","[rdx] = rbx"],[39,"mov rdx, qword [rbx + 0x8]","rdx = [rbx + 0x8]"],[43,"mov qword [rdx], rax","[rdx] = rax"],[46,"mov rdx, qword [rax + 0x8]","rdx = [rax + 0x8]"],[50,"mov qword [rdx], r15","[rdx] = r15"],[53,"mov rdx, qword [rax + 0x8]","rdx = [rax + 0x8]"],[57,"mov rbp, qword [rbx + 0x8]","rbp = [rbx + 0x8]"]]}
{"startAddress":"0x17a20","size":"0x3d","arch":"x86_64","syntax":["Intel","C style"],"instructions":[[0,"jl 0x179be","jl 0x179be"],[2,"add eax, dword [rax]","eax += [rax]"],[4,"mov edx, 0x38","edx = 0x38"],[9,"mov rcx, r15","rcx = r15"],[12,"call 0x39c6f","0x39c6f = call(0x39c6f)"],[17,"xor eax, eax","eax ^= eax"],[19,"jmp 0x17ad2","jmp 0x17ad2"],[24,"mov rbx, qword [r15]","rbx = [r15]"],[27,"cmp rbx, rax","rflags = flags(rbx - rax)"],[30,"jz 0x17a75","jz 0x17a75"],[32,"mov rdx, qword [r15 + 0x8]","rdx = [r15 + 0x8]"],[36,"mov qword [rdx], rbx","[rdx] = rbx"],[39,"mov rdx, qword [rbx + 0x8]","rdx = [rbx + 0x8]"],[43,"mov qword [rdx], rax","[rdx] = rax"],[46,"mov rdx, qword [rax + 0x8]","rdx = [rax + 0x8]"],[50,"mov qword [rdx], r15","[rdx] = r15"],[53,"mov rdx, qword [rax + 0x8]","rdx = [rax + 0x8]"],[57,"mov rbp, qword [rbx + 0x8]","rbp = [rbx + 0x8]"]]}
95 changes: 82 additions & 13 deletions samply-api/src/asm/mod.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -5,7 +5,8 @@ use samply_symbols::{
FileAndPathHelperError, LibraryInfo, SymbolManager,
};
use serde_json::json;
use yaxpeax_arch::{Arch, DecodeError, Reader, U8Reader};
use yaxpeax_arch::{Arch, DecodeError, LengthedInstruction, Reader, U8Reader};
use yaxpeax_x86::amd64::{Opcode, Operand};

use crate::asm::response_json::DecodedInstruction;

Expand Down Expand Up @@ -192,7 +193,8 @@ trait InstructionDecoding: Arch {
const SYNTAX: &'static [&'static str];
const ADJUST_BY_AFTER_ERROR: usize;
fn make_decoder() -> Self::Decoder;
fn stringify_inst(offset: u32, inst: Self::Instruction) -> DecodedInstruction;
fn stringify_inst(rel_address: u32, offset: u32, inst: Self::Instruction)
-> DecodedInstruction;
}

impl InstructionDecoding for yaxpeax_x86::amd64::Arch {
Expand All @@ -204,15 +206,70 @@ impl InstructionDecoding for yaxpeax_x86::amd64::Arch {
yaxpeax_x86::amd64::InstDecoder::default()
}

fn stringify_inst(offset: u32, inst: Self::Instruction) -> DecodedInstruction {
fn stringify_inst(
rel_address: u32,
offset: u32,
inst: Self::Instruction,
) -> DecodedInstruction {
let (mut intel_insn, mut c_insn) = (
inst.display_with(yaxpeax_x86::amd64::DisplayStyle::Intel)
.to_string(),
inst.display_with(yaxpeax_x86::amd64::DisplayStyle::C)
.to_string(),
);

fn is_relative_branch(opcode: Opcode) -> bool {
matches!(
opcode,
Opcode::JMP
| Opcode::JRCXZ
| Opcode::LOOP
| Opcode::LOOPZ
| Opcode::LOOPNZ
| Opcode::JO
| Opcode::JNO
| Opcode::JB
| Opcode::JNB
| Opcode::JZ
| Opcode::JNZ
| Opcode::JNA
| Opcode::JA
| Opcode::JS
| Opcode::JNS
| Opcode::JP
| Opcode::JNP
| Opcode::JL
| Opcode::JGE
| Opcode::JLE
| Opcode::JG
)
}

if is_relative_branch(inst.opcode()) {
match inst.operand(0) {
Operand::ImmediateI8(rel) => {
let dest = rel_address as i64
+ offset as i64
+ inst.len().to_const() as i64
+ rel as i64;
intel_insn = format!("{} 0x{:x}", inst.opcode(), dest);
c_insn = intel_insn.clone();
}
Operand::ImmediateI32(rel) => {
let dest = rel_address as i64
+ offset as i64
+ inst.len().to_const() as i64
+ rel as i64;
intel_insn = format!("{} 0x{:x}", inst.opcode(), dest);
c_insn = intel_insn.clone();
}
_ => {}
};
}

DecodedInstruction {
offset,
decoded_string_per_syntax: vec![
inst.display_with(yaxpeax_x86::amd64::DisplayStyle::Intel)
.to_string(),
inst.display_with(yaxpeax_x86::amd64::DisplayStyle::C)
.to_string(),
],
decoded_string_per_syntax: vec![intel_insn, c_insn],
}
}
}
Expand All @@ -226,7 +283,11 @@ impl InstructionDecoding for yaxpeax_x86::protected_mode::Arch {
yaxpeax_x86::protected_mode::InstDecoder::default()
}

fn stringify_inst(offset: u32, inst: Self::Instruction) -> DecodedInstruction {
fn stringify_inst(
_rel_address: u32,
offset: u32,
inst: Self::Instruction,
) -> DecodedInstruction {
DecodedInstruction {
offset,
decoded_string_per_syntax: vec![inst.to_string()],
Expand All @@ -243,7 +304,11 @@ impl InstructionDecoding for yaxpeax_arm::armv8::a64::ARMv8 {
yaxpeax_arm::armv8::a64::InstDecoder::default()
}

fn stringify_inst(offset: u32, inst: Self::Instruction) -> DecodedInstruction {
fn stringify_inst(
_rel_address: u32,
offset: u32,
inst: Self::Instruction,
) -> DecodedInstruction {
DecodedInstruction {
offset,
decoded_string_per_syntax: vec![inst.to_string()],
Expand Down Expand Up @@ -271,7 +336,11 @@ impl InstructionDecoding for yaxpeax_arm::armv7::ARMv7 {
yaxpeax_arm::armv7::InstDecoder::default_thumb()
}

fn stringify_inst(offset: u32, inst: Self::Instruction) -> DecodedInstruction {
fn stringify_inst(
_rel_address: u32,
offset: u32,
inst: Self::Instruction,
) -> DecodedInstruction {
DecodedInstruction {
offset,
decoded_string_per_syntax: vec![inst.to_string()],
Expand Down Expand Up @@ -300,7 +369,7 @@ where
let before = u64::from(reader.total_offset()) as u32;
match decoder.decode(&mut reader) {
Ok(inst) => {
instructions.push(A::stringify_inst(offset, inst));
instructions.push(A::stringify_inst(rel_address, offset, inst));
let after = u64::from(reader.total_offset()) as u32;
offset += after - before;
}
Expand Down