encodable: reject non-compact VarInts on Vec and Box<[T]> lengths

This commit is contained in:
Andrew Poelstra 2018-08-24 00:50:05 +00:00
parent f0221fb79b
commit ef642295c5
1 changed files with 69 additions and 7 deletions

View File

@ -115,14 +115,36 @@ impl<D: SimpleDecoder> ConsensusDecodable<D> for VarInt {
fn consensus_decode(d: &mut D) -> Result<VarInt, serialize::Error> { fn consensus_decode(d: &mut D) -> Result<VarInt, serialize::Error> {
let n = d.read_u8()?; let n = d.read_u8()?;
match n { match n {
0xFF => d.read_u64().map(|n| VarInt(u64::from_le(n))), 0xFF => {
0xFE => d.read_u32().map(|n| VarInt(u32::from_le(n) as u64)), let x = d.read_u64()?;
0xFD => d.read_u16().map(|n| VarInt(u16::from_le(n) as u64)), if x < 0x100000000 {
Err(serialize::Error::ParseFailed("non-minimal varint"))
} else {
Ok(VarInt(x))
}
}
0xFE => {
let x = d.read_u32()?;
if x < 0x10000 {
Err(serialize::Error::ParseFailed("non-minimal varint"))
} else {
Ok(VarInt(x as u64))
}
}
0xFD => {
let x = d.read_u16()?;
if x < 0xFD {
Err(serialize::Error::ParseFailed("non-minimal varint"))
} else {
Ok(VarInt(x as u64))
}
}
n => Ok(VarInt(n as u64)) n => Ok(VarInt(n as u64))
} }
} }
} }
// Booleans // Booleans
impl<S: SimpleEncoder> ConsensusEncodable<S> for bool { impl<S: SimpleEncoder> ConsensusEncodable<S> for bool {
#[inline] #[inline]
@ -202,7 +224,7 @@ impl<S: SimpleEncoder, T: ConsensusEncodable<S>> ConsensusEncodable<S> for Vec<T
impl<D: SimpleDecoder, T: ConsensusDecodable<D>> ConsensusDecodable<D> for Vec<T> { impl<D: SimpleDecoder, T: ConsensusDecodable<D>> ConsensusDecodable<D> for Vec<T> {
#[inline] #[inline]
fn consensus_decode(d: &mut D) -> Result<Vec<T>, serialize::Error> { fn consensus_decode(d: &mut D) -> Result<Vec<T>, serialize::Error> {
let VarInt(len): VarInt = ConsensusDecodable::consensus_decode(d)?; let len = VarInt::consensus_decode(d)?.0;
let byte_size = (len as usize) let byte_size = (len as usize)
.checked_mul(mem::size_of::<T>()) .checked_mul(mem::size_of::<T>())
.ok_or(serialize::Error::ParseFailed("Invalid length"))?; .ok_or(serialize::Error::ParseFailed("Invalid length"))?;
@ -223,7 +245,7 @@ impl<S: SimpleEncoder, T: ConsensusEncodable<S>> ConsensusEncodable<S> for Box<[
impl<D: SimpleDecoder, T: ConsensusDecodable<D>> ConsensusDecodable<D> for Box<[T]> { impl<D: SimpleDecoder, T: ConsensusDecodable<D>> ConsensusDecodable<D> for Box<[T]> {
#[inline] #[inline]
fn consensus_decode(d: &mut D) -> Result<Box<[T]>, serialize::Error> { fn consensus_decode(d: &mut D) -> Result<Box<[T]>, serialize::Error> {
let VarInt(len): VarInt = ConsensusDecodable::consensus_decode(d)?; let len = VarInt::consensus_decode(d)?.0;
let len = len as usize; let len = len as usize;
if len > MAX_VEC_SIZE { if len > MAX_VEC_SIZE {
return Err(serialize::Error::OversizedVectorAllocation { requested: len, max: MAX_VEC_SIZE }) return Err(serialize::Error::OversizedVectorAllocation { requested: len, max: MAX_VEC_SIZE })
@ -366,7 +388,7 @@ impl<D, K, V> ConsensusDecodable<D> for HashMap<K, V>
{ {
#[inline] #[inline]
fn consensus_decode(d: &mut D) -> Result<HashMap<K, V>, serialize::Error> { fn consensus_decode(d: &mut D) -> Result<HashMap<K, V>, serialize::Error> {
let VarInt(len): VarInt = ConsensusDecodable::consensus_decode(d)?; let len = VarInt::consensus_decode(d)?.0;
let mut ret = HashMap::with_capacity(len as usize); let mut ret = HashMap::with_capacity(len as usize);
for _ in 0..len { for _ in 0..len {
@ -384,7 +406,7 @@ impl<D, K, V> ConsensusDecodable<D> for HashMap<K, V>
mod tests { mod tests {
use super::{CheckedData, VarInt}; use super::{CheckedData, VarInt};
use network::serialize::{deserialize, serialize}; use network::serialize::{deserialize, serialize, Error};
#[test] #[test]
fn serialize_int_test() { fn serialize_int_test() {
@ -435,6 +457,46 @@ mod tests {
assert_eq!(serialize(&VarInt(0xF0F0F0F0F0E0)).ok(), Some(vec![0xFFu8, 0xE0, 0xF0, 0xF0, 0xF0, 0xF0, 0xF0, 0, 0])); assert_eq!(serialize(&VarInt(0xF0F0F0F0F0E0)).ok(), Some(vec![0xFFu8, 0xE0, 0xF0, 0xF0, 0xF0, 0xF0, 0xF0, 0, 0]));
} }
#[test]
fn deserialize_nonminimal_vec() {
match deserialize::<Vec<u8>>(&[0xfd, 0x00, 0x00]) {
Err(Error::ParseFailed("non-minimal varint")) => {},
x => panic!(x)
}
match deserialize::<Vec<u8>>(&[0xfd, 0xfc, 0x00]) {
Err(Error::ParseFailed("non-minimal varint")) => {},
x => panic!(x)
}
match deserialize::<Vec<u8>>(&[0xfe, 0xff, 0x00, 0x00, 0x00]) {
Err(Error::ParseFailed("non-minimal varint")) => {},
x => panic!(x)
}
match deserialize::<Vec<u8>>(&[0xfe, 0xff, 0xff, 0x00, 0x00]) {
Err(Error::ParseFailed("non-minimal varint")) => {},
x => panic!(x)
}
match deserialize::<Vec<u8>>(&[0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]) {
Err(Error::ParseFailed("non-minimal varint")) => {},
x => panic!(x)
}
match deserialize::<Vec<u8>>(&[0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00]) {
Err(Error::ParseFailed("non-minimal varint")) => {},
x => panic!(x)
}
let mut vec_256 = vec![0; 259];
vec_256[0] = 0xfd;
vec_256[1] = 0x00;
vec_256[2] = 0x01;
assert!(deserialize::<Vec<u8>>(&vec_256).is_ok());
let mut vec_253 = vec![0; 256];
vec_253[0] = 0xfd;
vec_253[1] = 0xfd;
vec_253[2] = 0x00;
assert!(deserialize::<Vec<u8>>(&vec_253).is_ok());
}
#[test] #[test]
fn serialize_checkeddata_test() { fn serialize_checkeddata_test() {
let cd = CheckedData(vec![1u8, 2, 3, 4, 5]); let cd = CheckedData(vec![1u8, 2, 3, 4, 5]);