1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242
use yaxpeax_arch::Arch;
use yaxpeax_arch::AddressBase;
use yaxpeax_arch::AddressDiff;
use yaxpeax_x86::long_mode::{Instruction, Operand, Opcode, RegSpec};
use yaxpeax_x86::x86_64;
use arch::x86_64::analyses::data_flow::{Data, Location, SymbolicExpression};
use analyses::evaluators::const_evaluator::{Domain, ConstEvaluator};
use analyses::static_single_assignment::SSA;
use data;
use data::modifier::ModifierExpression;
use data::ValueLocations;
use data::types::TypeSpec;
use memory::MemoryRange;
use analyses::Item;
use analyses::ValueOrImmediate;
use yaxpeax_arch::LengthedInstruction;
pub struct SymbolicDomain;
impl Domain for SymbolicDomain {
type Modifier = ModifierExpression;
type Value = SymbolicExpression;
fn join(l: Option<Self::Value>, r: Option<Self::Value>) -> Option<Self::Value> {
if l == r {
l
} else {
None
}
}
}
use std::rc::Rc;
pub(crate) fn referent(instr: &Instruction, mem_op: &Operand, addr: <x86_64 as Arch>::Address, dfg: &SSA<x86_64>, _contexts: &()) -> Option<Rc<Item<ValueOrImmediate<x86_64>>>> {
match mem_op {
Operand::DisplacementU32(disp) => {
if instr.prefixes.gs() {
if *disp < 0x10000 {
Some(
Item::opaque(TypeSpec::struct_pointer(data::types::KPCR)).add(&Item::immediate(*disp as i64))
)
} else {
// TODO
None
}
} else {
// TODO
None
}
}
Operand::DisplacementU64(disp) => {
if instr.prefixes.gs() {
if *disp < 0x10000 {
Some(
Item::opaque(TypeSpec::struct_pointer(data::types::KPCR)).add(&Item::immediate(*disp as i64))
)
} else {
// TODO
None
}
} else {
// TODO
None
}
}
Operand::RegDisp(RegSpec::RIP, disp) => {
let addr = (addr.wrapping_offset(instr.len())).wrapping_offset(AddressDiff::from_const(*disp as i64 as u64));
if addr == 0x1402a3148 {
// its that global struct referenced in ntoskrnl:0x1402a9370
// ... it's actually the linear address of the KPCR...
Some(Item::opaque(TypeSpec::struct_pointer(data::types::KPCR).pointer_to()))
} else if addr == 0x1402a3148 {
// its that global struct referenced in ntoskrnl:0x1402a9387
// stored in the KPCR, MAYBE??
Some(Item::opaque(TypeSpec::PointerTo(Rc::new(TypeSpec::Unknown)).pointer_to()))
} else {
None
}
}
Operand::RegDeref(reg) => {
match dfg.get_use(addr, Location::Register(*reg)).get_data().as_ref() {
Some(Data::Concrete(_v, None)) => {
// TODO: check const addr derefs for the same structures checked in disp
// eg gs:[rax] for rax = 0
None
},
Some(Data::Concrete(_v, Some(_ty))) => {
// TODO: check const addr derefs for the same structures checked in disp
// eg gs:[rax] for rax = 0
None
},
Some(Data::Expression(sym)) => Some(sym.to_owned()),
_ => None
}
},
Operand::RegDisp(reg, disp) => {
let reg = dfg.get_use(addr, Location::Register(*reg));
Some(Item::value(ValueOrImmediate::Value(reg.value)).add(&Item::immediate(*disp as i64)))
/*
match .get_data().as_ref() {
Some(Data::Concrete(_v, None)) => {
// v.wrapping_add(*disp as i64 as u64).unwrap();
// TODO: check const addr derefs for the same structures checked in disp
// eg gs:[rax] for rax = 0
None
},
Some(Data::Concrete(_v, Some(_ty))) => {
// v.wrapping_add(*disp as i64 as u64).unwrap();
// TODO: check const addr derefs for the same structures checked in disp
// eg gs:[rax] for rax = 0
None
},
Some(Data::Expression(sym)) => Some(sym.add(&Item::immediate(*disp as i64 as u64))),
_ => None
}
*/
},
Operand::RegScale(_reg, _scale) => {
None
},
Operand::RegIndexBase(_base, _index) => {
None
},
Operand::RegIndexBaseDisp(_base, _index, _disp) => {
None
}
Operand::RegScaleDisp(_base, _scale, _disp) => {
None
}
Operand::RegIndexBaseScale(_index, _base, _scale) => {
None
}
Operand::RegIndexBaseScaleDisp(_index, _base, _scale, _disp) => {
None
}
_ => None
}
}
impl ConstEvaluator<x86_64, (), SymbolicDomain> 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<<SymbolicDomain as Domain>::Modifier>, _dfg: &SSA<x86_64>, _contexts: &()) {
}
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) {
//TODO: handle prefixes like at all
match instr.opcode() {
Opcode::MOV => {
match (instr.operand(0), instr.operand(1)) {
(Operand::Register(l), op) => {
if op.is_memory() {
// println!("DOING MOV for {}", instr);
// `referent` is also called `effective_address` in other circumstances
// - either we can find an access expression known to `dfg` (in which
// case we might be able to just alias an existing value), otherwise
// it's a load of some opaque value.
if let Some(src) = referent(instr, &op, addr, dfg, contexts) {
use analyses::memory_layout::MemoryAccessBaseInference;
use crate::arch::x86_64::analyses::data_flow::ANY;
let def = dfg.get_def(addr, Location::Register(l));
if let Some((base, addend)) = MemoryAccessBaseInference::infer_base_and_addend(&src) {
// println!("inferred base and addend {:?}, {:?}", base, addend);
// println!(" def is {:?}={:p}", def.value, def.value.as_ptr());
if let Some(memory) = dfg.try_get_use(addr, Location::MemoryLocation(ANY, 8 /* l.width() */, Some((Data::Expression(base), Data::Expression(addend))))) {
// println!(" AND aliasing to {:?}, was {:?}", memory, def.get_data());
def.update(Data::Alias(Rc::clone(&memory)));
// println!(" DONE aliasing to {:?}, is {:?}", memory, dfg.get_def(addr, Location::Register(l)).value);
return;
} else {
if def.get_data().is_none() {
def.update(
Data::Expression(Item::load(&src, l.width()))
)
}
}
} else {
if def.get_data().is_none() {
def.update(
Data::Expression(Item::load(&src, l.width()))
)
}
}
}
}
},
(op, Operand::Register(r)) => {
if op.is_memory() {
// `referent` is also called `effective_address` in other circumstances
// - either we can find an access expression known to `dfg` (in which
// case we might be able to just alias an existing value), otherwise
// it's a load of some opaque value.
if let Some(src) = referent(instr, &op, addr, dfg, contexts) {
use analyses::memory_layout::MemoryAccessBaseInference;
use crate::arch::x86_64::analyses::data_flow::ANY;
let usage = dfg.get_use(addr, Location::Register(r));
if let Some((base, addend)) = MemoryAccessBaseInference::infer_base_and_addend(&src) {
// println!("inferred base and addend {:?}, {:?}", base, addend);
if let Some(def) = dfg.try_get_def(addr, Location::MemoryLocation(ANY, 8 /* l.width() */, Some((Data::Expression(base), Data::Expression(addend))))) {
def.borrow_mut().data.replace(Data::Alias(Rc::clone(&usage.value)));
}
}
}
}
},
_ => {
// don't handle others yet
}
}
}
Opcode::ADD => {
match instr.operand(0) {
Operand::Register(l) => {
let offset = match instr.operand(1) {
Operand::ImmediateI64(i) => i,
Operand::ImmediateI32(i) => i as i64,
Operand::ImmediateI8(i) => i as i64,
_ => {
// don't handle these yet
return;
}
};
let use_val = dfg.get_use(addr, Location::Register(l));
let def_val = dfg.get_def(addr, Location::Register(l));
// println!("Symbolizing use {:?} + {:#x} = ...", use_val.get_data(), i);
match use_val.get_data().as_ref() {
Some(Data::Expression(expr)) => {
// println!(" = {:?}", expr.clone().offset(*i as i64 as u64));
def_val.update(Data::Expression(expr.add(&Item::immediate(offset))));
}
_ => { }
};
}
_ => {
// don't handle others yet
}
}
}
_ => { }
}
}
}