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use yaxpeax_arch::{Arch, AddressDisplay};
use yaxpeax_x86::long_mode::{Instruction, Operand, Opcode, RegSpec, register_class};
use yaxpeax_x86::x86_64;
use arch::x86_64::analyses::data_flow::{Data, Location, ValueRange};
use analyses::evaluators::const_evaluator::{Domain, ConstEvaluator};
use analyses::static_single_assignment::SSA;
use analyses::static_single_assignment::{DataDisplay as SSADataDisplay};
use data::Direction;
use data::modifier::ModifierExpression;
use data::ValueLocations;
use memory::MemoryRange;
use tracing::{event, Level};
pub struct ValueSetDomain;
impl Domain for ValueSetDomain {
type Modifier = ModifierExpression;
type Value = Vec<ValueRange>;
fn join(_l: Option<Self::Value>, _r: Option<Self::Value>) -> Option<Self::Value> {
panic!("implement value set domain join");
}
}
fn referent(_instr: &Instruction, mem_op: &Operand, addr: <x86_64 as Arch>::Address, dfg: &SSA<x86_64>, _contexts: &()) -> Option<Data> {
match mem_op {
Operand::DisplacementU32(_) |
Operand::DisplacementU64(_) => {
None
}
Operand::RegDeref(reg) => {
match dfg.get_use(addr, Location::Register(*reg)).get_data().as_ref() {
Some(Data::ValueSet(values)) => {
Some(Data::ValueSet(values.clone()))
}
_ => None
}
},
Operand::RegDisp(RegSpec::RIP, _) => {
None
},
Operand::RegDisp(reg, disp) => {
match dfg.get_use(addr, Location::Register(*reg)).get_data().as_ref() {
Some(Data::ValueSet(values)) => {
Data::add(&Data::ValueSet(values.clone()), &Data::Concrete(*disp as i64 as u64, None))
}
_ => None
}
},
Operand::RegScale(_reg, _scale) => {
None
},
Operand::RegIndexBase(_base, _index) => {
None
},
Operand::RegIndexBaseDisp(base, index, disp) => {
if addr == 0x1404d5d88 {
println!("mem operand: {:?}", mem_op);
}
let referent = match (dfg.get_use(addr, Location::Register(*base)).get_data().as_ref(), dfg.get_use(addr, Location::Register(*index)).get_data().as_ref()) {
(Some(Data::ValueSet(base_values)), Some(Data::Concrete(i, _))) => {
Data::add(&Data::ValueSet(base_values.clone()), &Data::Concrete(i.wrapping_add(*disp as i64 as u64), None))
}
(Some(Data::Concrete(base_value, _)), Some(Data::ValueSet(index_values))) => {
Data::add(&Data::ValueSet(index_values.clone()), &Data::Concrete(base_value.wrapping_add(*disp as u64), None))
}
_ => None
};
if addr == 0x1404d5d88 {
println!("Computed referent: {:?}", referent);
}
referent
}
Operand::RegScaleDisp(base, scale, disp) => {
let referent = match dfg.get_use(addr, Location::Register(*base)).get_data().as_ref().and_then(|x| Data::underlying(x)) {
Some(Data::ValueSet(base_values)) => {
if let Some(scaled) = Data::mul(&Data::ValueSet(base_values.clone()), &Data::Concrete(*scale as u64, None)) {
Data::add(&scaled, &Data::Concrete(*disp as i64 as u64, None))
} else {
None
}
}
_ => None
};
referent
}
Operand::RegIndexBaseScale(_index, _base, _scale) => {
None
}
Operand::RegIndexBaseScaleDisp(base, index, scale, disp) => {
if addr == 0x140486bc0 {
println!("mem operand: {:?}", mem_op);
}
let referent = match (dfg.get_use(addr, Location::Register(*base)).get_data().as_ref(), dfg.get_use(addr, Location::Register(*index)).get_data().as_ref()) {
(Some(Data::ValueSet(base_values)), Some(Data::Concrete(i, _))) => {
Data::add(&Data::ValueSet(base_values.clone()), &Data::Concrete(i.wrapping_mul(*scale as u64).wrapping_add(*disp as i64 as u64), None))
}
(Some(Data::Concrete(base_value, _)), Some(Data::ValueSet(index_values))) => {
let multiplied_values = Data::mul(&Data::ValueSet(index_values.clone()), &Data::Concrete(*scale as u64, None));
if addr == 0x140486bc0 {
println!("Multiplied indices: {:?}", multiplied_values);
}
multiplied_values
.as_ref().and_then(|d| Data::add(d, &Data::Concrete(base_value.wrapping_add(*disp as u64), None)))
}
_ => None
};
referent
}
_ => None
}
}
fn valueset_deref<U: MemoryRange<x86_64>>(values: Vec<ValueRange>, data: &U, size: u8) -> Option<Vec<ValueRange>> {
let mut reads: Vec<ValueRange> = Vec::new();
for value in values {
match value {
ValueRange::Between(Data::Concrete(low, _), Data::Concrete(high, _)) => {
if high - low > 0x10000 {
event!(Level::WARN, "suspiciously large valueset deref range");
return None;
}
for v in low..=high {
let mut read_value = 0u64;
for i in 0..size {
if let Some(value) = data.read(v + i as u64) {
read_value |= (value as u64) << (8 * i);
} else {
tracing::error!("read of {:#x} failed?", v + i as u64);
return None;
}
}
let new_value = ValueRange::Precisely(Data::Concrete(read_value, None));
if !reads.contains(&new_value) {
reads.push(new_value);
}
}
}
ValueRange::Between(_, _) => {
},
ValueRange::Precisely(value) => {
match value {
Data::Concrete(v, _) => {
let mut read_value = 0u64;
for i in 0..size {
if let Some(value) = data.read(v + i as u64) {
read_value |= (value as u64) << (8 * i);
} else {
tracing::error!("read of {:#x} failed?", v + i as u64);
return None;
}
}
let new_value = ValueRange::Precisely(Data::Concrete(read_value, None));
if !reads.contains(&new_value) {
reads.push(new_value);
}
},
_ => {
}
}
}
}
}
if reads.len() > 0 {
Some(reads)
} else {
None
}
}
impl ConstEvaluator<x86_64, (), ValueSetDomain> for x86_64 {
fn apply_transient(from: <x86_64 as Arch>::Address, to: <x86_64 as Arch>::Address, location: Option<<x86_64 as ValueLocations>::Location>, exprs: &Vec<<ValueSetDomain as Domain>::Modifier>, dfg: &SSA<x86_64>, _contexts: &()) {
if let Some(loc) = location {
for expr in exprs {
let new_value = dfg.get_transient_value(from, to, loc.clone(), Direction::Read).and_then(|_lvalue| {
None
}).unwrap_or_else(|| {
match expr {
ModifierExpression::Above(v) => {
Some(Data::ValueSet(
vec![ValueRange::Between(
Data::Concrete(*v, None),
Data::Concrete(0xffffffff_ffffffff, None)
)]
))
}
ModifierExpression::Below(v) => {
Some(Data::ValueSet(
vec![ValueRange::Between(
Data::Concrete(0, None),
Data::Concrete(*v, None)
)]
))
}
ModifierExpression::Is(v) => {
Some(Data::Concrete(*v, None))
}
ModifierExpression::IsNot(_) => {
None
}
}
});
if let Some(new_value) = new_value {
dfg.get_transient_def(from, to, loc.clone()).update(new_value);
} else {
dfg.get_transient_def(from, to, loc.clone()).clear();
}
}
} else {
}
}
fn evaluate_instruction<U: MemoryRange<x86_64>>(instr: &<x86_64 as Arch>::Instruction, addr: <x86_64 as Arch>::Address, dfg: &SSA<x86_64>, contexts: &(), data: &U) {
match instr.opcode() {
Opcode::MOVSXD => {
match (instr.operand(0), instr.operand(1)) {
(Operand::Register(l), Operand::Register(r)) => {
dfg.get_def(addr, Location::Register(l)).replace(
dfg.get_use(addr, Location::Register(r)).get_data().clone()
);
}
_ => {}
}
}
Opcode::MOVZX => {
match (instr.operand(0), instr.operand(1)) {
(Operand::Register(l), op) => {
if op.is_memory() {
if let Some(Data::ValueSet(value_set)) = referent(instr, &op, addr, dfg, contexts) {
if let Some(read_values) = valueset_deref(value_set.clone(), data, instr.mem_size().unwrap().bytes_size().unwrap()) {
let values = Data::ValueSet(value_set);
let read_values = Data::ValueSet(read_values);
tracing::info!(
"at {}, derefed value set {} to read {}",
addr.show(),
values.display(false, None),
read_values.display(false, None),
);
dfg.get_def(addr, Location::Register(l)).update(
read_values
);
} else {
}
} else {
}
} else {
}
}
_ => {}
}
}
Opcode::MOV => {
match (instr.operand(0), instr.operand(1)) {
(Operand::Register(l), op) => {
if op.is_memory() {
if let Some(Data::ValueSet(value_set)) = referent(instr, &op, addr, dfg, contexts) {
let size = match l.class() {
register_class::Q => 8,
register_class::D => 4,
register_class::W => 2,
register_class::B |
register_class::RB => 1,
_ => {
return;
}
};
if let Some(read_values) = valueset_deref(value_set.clone(), data, size) {
let values = Data::ValueSet(value_set);
let read_values = Data::ValueSet(read_values);
eprintln!(
"Derefed value set {} to read {}",
values.display(false, None),
read_values.display(false, None),
);
dfg.get_def(addr, Location::Register(l)).update(
read_values
);
} else {
}
} else {
}
} else {
}
}
_ => {}
}
}
Opcode::JMP => {
let jmpop = instr.operand(0);
if jmpop.is_memory() {
if let Some(Data::ValueSet(values)) = referent(instr, &jmpop, addr, dfg, contexts) {
if let Some(read_values) = valueset_deref(values.clone(), data, 8) {
tracing::info!(" jump table with {} entries:", read_values.len());
for ent in read_values {
match ent {
ValueRange::Precisely(Data::Concrete(ent, _)) => {
tracing::info!(" {:#x}", ent);
}
entry => {
tracing::warn!("can't process unknown value range entry: {:?}", entry);
}
}
}
}
}
}
}
Opcode::ADD => {
match (instr.operand(0), instr.operand(1)) {
(Operand::Register(l), Operand::Register(r)) => {
dfg.get_def(addr, Location::Register(l)).replace(
dfg.get_use(addr, Location::Register(l)).get_data().as_ref().and_then(|ldata| {
dfg.get_use(addr, Location::Register(r)).get_data().as_ref().and_then(|rdata| {
Data::add(&ldata, &rdata)
})
})
);
}
_ => {}
}
}
_ => { }
}
}
}