cerc-io/lighthouse
16
0
Fork 0
Code Issues 1 Pull Requests Packages Projects Releases Wiki Activity

Merge branch 'shuffle_underflow' into genesis

Browse Source
This commit is contained in:
Paul Hauner 2018-10-22 06:17:02 +11:00
commit 41bfb7a0e2
No known key found for this signature in database
GPG Key ID: 303E4494BB28068C
5 changed files with 214 additions and 50 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

81
beacon_chain/utils/ssz_helpers/src/ssz_beacon_block.rs
View File

@ -14,7 +14,16 @@ pub enum SszBeaconBlockError {
TooLong,
}
const LENGTH_BYTES: usize = 4;
/*
* Constants used for navigating the SSZ bytes.
*/
const LENGTH_PREFIX_BYTES: usize = 4;
const SLOT_BYTES: usize = 8;
const HASH_SIZE: usize = 32;
const RANDAO_REVEAL_BYTES: usize = HASH_SIZE;
const POW_CHAIN_REF_BYTES: usize = HASH_SIZE;
const ACTIVE_STATE_BYTES: usize = HASH_SIZE;
const CRYSTALLIZED_STATE_BYTES: usize = HASH_SIZE;
/// Allows for reading of block values directly from serialized ssz bytes.
///
@ -74,41 +83,35 @@ impl<'a> SszBeaconBlock<'a> {
* Determine how many bytes are used to store ancestor hashes.
*/
let ancestors_position =
8 + // slot
32 + // randao_reveal
32; // pow_chain_reference
let ancestors_len = decode_length(untrimmed_ssz, ancestors_position, LENGTH_BYTES)
SLOT_BYTES +
RANDAO_REVEAL_BYTES +
POW_CHAIN_REF_BYTES;
let ancestors_len = decode_length(untrimmed_ssz, ancestors_position, LENGTH_PREFIX_BYTES)
.map_err(|_| SszBeaconBlockError::TooShort)?;
/*
* Determine how many bytes are used to store attestation records.
*/
let attestations_position =
ancestors_position + LENGTH_BYTES + ancestors_len + // end of ancestor bytes
32 + // active_state_root
32; // crystallized_state_root
let attestations_len = decode_length(untrimmed_ssz, attestations_position, LENGTH_BYTES)
ancestors_position + LENGTH_PREFIX_BYTES + ancestors_len + // end of ancestor bytes
ACTIVE_STATE_BYTES +
CRYSTALLIZED_STATE_BYTES;
let attestations_len = decode_length(untrimmed_ssz, attestations_position, LENGTH_PREFIX_BYTES)
.map_err(|_| SszBeaconBlockError::TooShort)?;
/*
* Determine how many bytes are used to store specials.
*/
let specials_position =
attestations_position + // location of attestations
LENGTH_BYTES + // attestations length prefix
attestations_len; // # of attestation bytes
let specials_len = decode_length(untrimmed_ssz, specials_position, LENGTH_BYTES)
let specials_position = attestations_position + LENGTH_PREFIX_BYTES + attestations_len;
let specials_len = decode_length(untrimmed_ssz, specials_position, LENGTH_PREFIX_BYTES)
.map_err(|_| SszBeaconBlockError::TooShort)?;
/*
* Now that all variable field lengths are known (ancestors, attestations, specials) we can
* know the exact length of the block and reject it if the slice is too short.
*/
let block_ssz_len = {
MIN_SSZ_BLOCK_LENGTH + ancestors_len + attestations_len + specials_len
};
let block_ssz_len = MIN_SSZ_BLOCK_LENGTH + ancestors_len + attestations_len + specials_len;
if vec.len() < block_ssz_len {
println!("block_ssz_len: {:?}, len: {:?}", block_ssz_len, vec.len());
return Err(SszBeaconBlockError::TooShort);
}
@ -135,12 +138,8 @@ impl<'a> SszBeaconBlock<'a> {
/// The first hash in `ancestor_hashes` is the parent of the block.
pub fn parent_hash(&self) -> Option<&[u8]> {
let ancestor_ssz = self.ancestor_hashes();
let start = LENGTH_BYTES;
if ancestor_ssz.len() >= 32 {
Some(&ancestor_ssz[start..start + 32])
} else {
None
}
let start = LENGTH_PREFIX_BYTES;
ancestor_ssz.get(start..start + HASH_SIZE)
}
/// Return the `slot` field.
@ -162,54 +161,54 @@ impl<'a> SszBeaconBlock<'a> {
/// Return the `randao_reveal` field.
pub fn randao_reveal(&self) -> &[u8] {
let start = 8; // slot is 8 bytes
&self.ssz[start..start + 32]
let start = SLOT_BYTES;
&self.ssz[start..start + RANDAO_REVEAL_BYTES]
}
/// Return the `pow_chain_reference` field.
pub fn pow_chain_reference(&self) -> &[u8] {
let start =
8 + // slot
32; // randao_reveal
&self.ssz[start..start + 32]
SLOT_BYTES +
RANDAO_REVEAL_BYTES;
&self.ssz[start..start + POW_CHAIN_REF_BYTES]
}
/// Return the serialized `ancestor_hashes` bytes, including length prefix.
pub fn ancestor_hashes(&self) -> &[u8] {
let start = self.ancestors_position;
&self.ssz[start..(start + self.ancestors_len + LENGTH_BYTES)]
&self.ssz[start..(start + self.ancestors_len + LENGTH_PREFIX_BYTES)]
}
/// Return the `active_state_root` field.
pub fn act_state_root(&self) -> &[u8] {
let start = self.ancestors_position + LENGTH_BYTES + self.ancestors_len;
let start = self.ancestors_position + LENGTH_PREFIX_BYTES + self.ancestors_len;
&self.ssz[start..(start + 32)]
}
/// Return the `active_state_root` field.
pub fn cry_state_root(&self) -> &[u8] {
let start =
self.ancestors_position + LENGTH_BYTES + self.ancestors_len + // ancestors
32; // active_state_root;
self.ancestors_position + LENGTH_PREFIX_BYTES + self.ancestors_len +
ACTIVE_STATE_BYTES;
&self.ssz[start..(start + 32)]
}
/// Return the serialized `attestations` bytes, including length prefix.
pub fn attestations(&self) -> &[u8] {
let start = self.attestations_position;
&self.ssz[start..(start + self.attestations_len + LENGTH_BYTES)]
&self.ssz[start..(start + self.attestations_len + LENGTH_PREFIX_BYTES)]
}
/// Return the serialized `attestations` bytes _without_ the length prefix.
pub fn attestations_without_length(&self) -> &[u8] {
let start = self.attestations_position + LENGTH_BYTES;
let start = self.attestations_position + LENGTH_PREFIX_BYTES;
&self.ssz[start..start + self.attestations_len]
}
/// Return the serialized `specials` bytes, including length prefix.
pub fn specials(&self) -> &[u8] {
let start = self.specials_position;
&self.ssz[start..(start + self.specials_len + LENGTH_BYTES)]
&self.ssz[start..(start + self.specials_len + LENGTH_PREFIX_BYTES)]
}
}
@ -349,7 +348,7 @@ mod tests {
let serialized = get_block_ssz(&block);
let ssz_block = SszBeaconBlock::from_slice(&serialized).unwrap();
let mut expected = encode_length(32, LENGTH_BYTES);
let mut expected = encode_length(32, LENGTH_PREFIX_BYTES);
expected.append(&mut h.to_vec());
assert_eq!(ssz_block.ancestor_hashes(), &expected[..]);
@ -383,7 +382,7 @@ mod tests {
let ssz_block = SszBeaconBlock::from_slice(&serialized).unwrap();
let sr_ssz = get_special_record_ssz(&s);
let mut expected = encode_length(sr_ssz.len(), LENGTH_BYTES);
let mut expected = encode_length(sr_ssz.len(), LENGTH_PREFIX_BYTES);
expected.append(&mut sr_ssz.to_vec());
assert_eq!(ssz_block.specials(), &expected[..]);
@ -399,7 +398,7 @@ mod tests {
let ssz_block = SszBeaconBlock::from_slice(&serialized).unwrap();
let sr_ssz = get_special_record_ssz(&s);
let mut expected = encode_length(sr_ssz.len(), LENGTH_BYTES);
let mut expected = encode_length(sr_ssz.len(), LENGTH_PREFIX_BYTES);
expected.append(&mut sr_ssz.to_vec());
assert_eq!(ssz_block.specials(), &expected[..]);
@ -417,7 +416,7 @@ mod tests {
let ssz_block = SszBeaconBlock::from_slice(&serialized).unwrap();
let ssz_ar = get_attestation_record_ssz(&AttestationRecord::zero());
let mut expected = encode_length(ssz_ar.len(), LENGTH_BYTES);
let mut expected = encode_length(ssz_ar.len(), LENGTH_PREFIX_BYTES);
expected.append(&mut ssz_ar.to_vec());
assert_eq!(ssz_block.attestations(), &expected[..]);
@ -434,7 +433,7 @@ mod tests {
let mut ssz_ar = get_attestation_record_ssz(&AttestationRecord::zero());
ssz_ar.append(&mut get_attestation_record_ssz(&AttestationRecord::zero()));
let mut expected = encode_length(ssz_ar.len(), LENGTH_BYTES);
let mut expected = encode_length(ssz_ar.len(), LENGTH_PREFIX_BYTES);
expected.append(&mut ssz_ar.to_vec());
assert_eq!(ssz_block.attestations(), &expected[..]);

3
beacon_chain/utils/vec_shuffle/Cargo.toml
View File

@ -5,3 +5,6 @@ authors = ["Paul Hauner <paul@paulhauner.com>"]
[dependencies]
hashing = { path = "../hashing" }
[dev-dependencies]
yaml-rust = "0.4.2"

45
beacon_chain/utils/vec_shuffle/src/lib.rs
View File

@ -25,10 +25,16 @@ pub fn shuffle<T>(
-> Result<Vec<T>, ShuffleErr>
{
let mut rng = ShuffleRng::new(seed);
if list.len() > rng.rand_max as usize {
return Err(ShuffleErr::ExceedsListLength);
}
for i in 0..(list.len() - 1) {
if list.is_empty() {
return Ok(list);
}
for i in 0..(list.len().saturating_sub(1)) {
let n = list.len() - i;
let j = rng.rand_range(n as u32) as usize + i;
list.swap(i, j);
@ -39,17 +45,40 @@ pub fn shuffle<T>(
#[cfg(test)]
mod tests {
extern crate yaml_rust;
use super::*;
use super::hashing::canonical_hash;
use std::fs::File;
use std::io::prelude::*;
use self::yaml_rust::yaml;
#[test]
fn test_shuffling() {
let seed = canonical_hash(b"4kn4driuctg8");
let list: Vec<usize> = (0..12).collect();
let s = shuffle(&seed, list).unwrap();
assert_eq!(
s,
vec![7, 3, 2, 5, 11, 9, 1, 0, 4, 6, 10, 8],
)
let mut file = File::open("./src/specs/shuffle_test_vectors.yaml").unwrap();
let mut yaml_str = String::new();
file.read_to_string(&mut yaml_str).unwrap();
let docs = yaml::YamlLoader::load_from_str(&yaml_str).unwrap();
let doc = &docs[0];
let test_cases = doc["test_cases"].as_vec();
for test_case in test_cases.unwrap() {
let input = test_case["input"].clone().into_vec().unwrap();
let output = test_case["output"].clone().into_vec().unwrap();
let seed_bytes = test_case["seed"].as_str().unwrap().as_bytes();
let mut seed;
if seed_bytes.len() > 0 {
seed = canonical_hash(seed_bytes);
} else {
seed = vec![];
}
let mut s = shuffle(&seed, input).unwrap();
assert_eq!(s, output);
}
}
}

2
beacon_chain/utils/vec_shuffle/src/rng.rs
View File

@ -2,7 +2,7 @@ use super::hashing::canonical_hash;
const SEED_SIZE_BYTES: usize = 32;
const RAND_BYTES: usize = 3; // 24 / 8
const RAND_MAX: u32 = 16_777_216; // 2**24
const RAND_MAX: u32 = 16_777_215; // 2 ** (rand_bytes * 8) - 1
/// A pseudo-random number generator which given a seed
/// uses successive blake2s hashing to generate "entropy".

133
beacon_chain/utils/vec_shuffle/src/specs/shuffle_test_vectors.yaml Normal file
View File

@ -0,0 +1,133 @@
# This file was generated with sigp/shuffling_sandbox
# python3 sandbox.py test_vectors
title: Shuffling Algorithm Tests
summary: Test vectors for shuffling a list based upon a seed.
test_suite: Shuffling
test_cases:
- input: []
output: []
seed: ''
- input: [0]
output: [0]
seed: ''
- input: [255]
output: [255]
seed: ''
- input: [4, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [1, 6, 4, 1, 6, 6, 2, 2, 4, 5]
seed: ''
- input: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
output: [4, 7, 10, 13, 3, 1, 2, 9, 12, 6, 11, 8, 5]
seed: ''
- input: [65, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [1, 6, 65, 1, 6, 6, 2, 2, 4, 5]
seed: ''
- input: []
output: []
seed: 4kn4driuctg8
- input: [0]
output: [0]
seed: 4kn4driuctg8
- input: [255]
output: [255]
seed: 4kn4driuctg8
- input: [4, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [6, 4, 2, 5, 4, 2, 6, 6, 1, 1]
seed: 4kn4driuctg8
- input: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
output: [13, 1, 9, 8, 3, 10, 6, 2, 5, 12, 11, 4, 7]
seed: 4kn4driuctg8
- input: [65, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [6, 65, 2, 5, 4, 2, 6, 6, 1, 1]
seed: 4kn4driuctg8
- input: []
output: []
seed: ytre1p
- input: [0]
output: [0]
seed: ytre1p
- input: [255]
output: [255]
seed: ytre1p
- input: [4, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [6, 2, 5, 1, 6, 4, 1, 2, 4, 6]
seed: ytre1p
- input: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
output: [3, 8, 10, 4, 7, 11, 6, 1, 2, 5, 13, 9, 12]
seed: ytre1p
- input: [65, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [6, 2, 5, 1, 6, 4, 1, 2, 65, 6]
seed: ytre1p
- input: []
output: []
seed: mytobcffnkvj
- input: [0]
output: [0]
seed: mytobcffnkvj
- input: [255]
output: [255]
seed: mytobcffnkvj
- input: [4, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [5, 6, 2, 1, 6, 4, 6, 4, 1, 2]
seed: mytobcffnkvj
- input: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
output: [12, 4, 11, 6, 13, 10, 9, 2, 3, 7, 8, 1, 5]
seed: mytobcffnkvj
- input: [65, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [5, 6, 2, 1, 6, 65, 6, 4, 1, 2]
seed: mytobcffnkvj
- input: []
output: []
seed: myzu3g7evxp5nkvj
- input: [0]
output: [0]
seed: myzu3g7evxp5nkvj
- input: [255]
output: [255]
seed: myzu3g7evxp5nkvj
- input: [4, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [6, 2, 6, 5, 4, 4, 1, 6, 2, 1]
seed: myzu3g7evxp5nkvj
- input: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
output: [10, 12, 13, 3, 7, 11, 2, 4, 9, 8, 6, 5, 1]
seed: myzu3g7evxp5nkvj
- input: [65, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [6, 2, 6, 5, 65, 4, 1, 6, 2, 1]
seed: myzu3g7evxp5nkvj
- input: []
output: []
seed: xdpli1jsx5xb
- input: [0]
output: [0]
seed: xdpli1jsx5xb
- input: [255]
output: [255]
seed: xdpli1jsx5xb
- input: [4, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [6, 2, 4, 1, 2, 6, 5, 1, 6, 4]
seed: xdpli1jsx5xb
- input: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
output: [11, 8, 12, 9, 2, 1, 10, 4, 13, 5, 7, 3, 6]
seed: xdpli1jsx5xb
- input: [65, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [6, 2, 65, 1, 2, 6, 5, 1, 6, 4]
seed: xdpli1jsx5xb
- input: []
output: []
seed: oab3mbb3xe8qsx5xb
- input: [0]
output: [0]
seed: oab3mbb3xe8qsx5xb
- input: [255]
output: [255]
seed: oab3mbb3xe8qsx5xb
- input: [4, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [2, 5, 1, 6, 1, 2, 6, 6, 4, 4]
seed: oab3mbb3xe8qsx5xb
- input: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
output: [5, 13, 9, 7, 11, 10, 12, 2, 6, 8, 3, 1, 4]
seed: oab3mbb3xe8qsx5xb
- input: [65, 6, 2, 6, 1, 4, 6, 2, 1, 5]
output: [2, 5, 1, 6, 1, 2, 6, 6, 65, 4]
seed: oab3mbb3xe8qsx5xb