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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /vendor/ahash/src/hash_quality_test.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/ahash/src/hash_quality_test.rs')
-rw-r--r--vendor/ahash/src/hash_quality_test.rs483
1 files changed, 483 insertions, 0 deletions
diff --git a/vendor/ahash/src/hash_quality_test.rs b/vendor/ahash/src/hash_quality_test.rs
new file mode 100644
index 000000000..4cd3156af
--- /dev/null
+++ b/vendor/ahash/src/hash_quality_test.rs
@@ -0,0 +1,483 @@
+use core::hash::{Hash, Hasher};
+use std::collections::HashMap;
+
+fn assert_sufficiently_different(a: u64, b: u64, tolerance: i32) {
+ let (same_byte_count, same_nibble_count) = count_same_bytes_and_nibbles(a, b);
+ assert!(same_byte_count <= tolerance, "{:x} vs {:x}: {:}", a, b, same_byte_count);
+ assert!(
+ same_nibble_count <= tolerance * 3,
+ "{:x} vs {:x}: {:}",
+ a,
+ b,
+ same_nibble_count
+ );
+ let flipped_bits = (a ^ b).count_ones();
+ assert!(
+ flipped_bits > 12 && flipped_bits < 52,
+ "{:x} and {:x}: {:}",
+ a,
+ b,
+ flipped_bits
+ );
+ for rotate in 0..64 {
+ let flipped_bits2 = (a ^ (b.rotate_left(rotate))).count_ones();
+ assert!(
+ flipped_bits2 > 10 && flipped_bits2 < 54,
+ "{:x} and {:x}: {:}",
+ a,
+ b.rotate_left(rotate),
+ flipped_bits2
+ );
+ }
+}
+
+fn count_same_bytes_and_nibbles(a: u64, b: u64) -> (i32, i32) {
+ let mut same_byte_count = 0;
+ let mut same_nibble_count = 0;
+ for byte in 0..8 {
+ let ba = (a >> (8 * byte)) as u8;
+ let bb = (b >> (8 * byte)) as u8;
+ if ba == bb {
+ same_byte_count += 1;
+ }
+ if ba & 0xF0u8 == bb & 0xF0u8 {
+ same_nibble_count += 1;
+ }
+ if ba & 0x0Fu8 == bb & 0x0Fu8 {
+ same_nibble_count += 1;
+ }
+ }
+ (same_byte_count, same_nibble_count)
+}
+
+fn gen_combinations(options: &[u32; 8], depth: u32, so_far: Vec<u32>, combinations: &mut Vec<Vec<u32>>) {
+ if depth == 0 {
+ return;
+ }
+ for option in options {
+ let mut next = so_far.clone();
+ next.push(*option);
+ combinations.push(next.clone());
+ gen_combinations(options, depth - 1, next, combinations);
+ }
+}
+
+fn test_no_full_collisions<T: Hasher>(gen_hash: impl Fn() -> T) {
+ let options: [u32; 8] = [
+ 0x00000000, 0x20000000, 0x40000000, 0x60000000, 0x80000000, 0xA0000000, 0xC0000000, 0xE0000000,
+ ];
+ let mut combinations = Vec::new();
+ gen_combinations(&options, 7, Vec::new(), &mut combinations);
+ let mut map: HashMap<u64, Vec<u8>> = HashMap::new();
+ for combination in combinations {
+ let array = unsafe {
+ let (begin, middle, end) = combination.align_to::<u8>();
+ assert_eq!(0, begin.len());
+ assert_eq!(0, end.len());
+ middle.to_vec()
+ };
+ let mut hasher = gen_hash();
+ hasher.write(&array);
+ let hash = hasher.finish();
+ if let Some(value) = map.get(&hash) {
+ assert_eq!(
+ value, &array,
+ "Found a collision between {:x?} and {:x?}. Hash: {:x?}",
+ value, &array, &hash
+ );
+ } else {
+ map.insert(hash, array);
+ }
+ }
+ assert_eq!(2396744, map.len());
+}
+
+fn test_keys_change_output<T: Hasher>(constructor: impl Fn(u128, u128) -> T) {
+ let mut a = constructor(1, 1);
+ let mut b = constructor(1, 2);
+ let mut c = constructor(2, 1);
+ let mut d = constructor(2, 2);
+ "test".hash(&mut a);
+ "test".hash(&mut b);
+ "test".hash(&mut c);
+ "test".hash(&mut d);
+ assert_sufficiently_different(a.finish(), b.finish(), 1);
+ assert_sufficiently_different(a.finish(), c.finish(), 1);
+ assert_sufficiently_different(a.finish(), d.finish(), 1);
+ assert_sufficiently_different(b.finish(), c.finish(), 1);
+ assert_sufficiently_different(b.finish(), d.finish(), 1);
+ assert_sufficiently_different(c.finish(), d.finish(), 1);
+}
+
+fn test_input_affect_every_byte<T: Hasher>(constructor: impl Fn(u128, u128) -> T) {
+ let base = hash_with(&0, constructor(0, 0));
+ for shift in 0..16 {
+ let mut alternitives = vec![];
+ for v in 0..256 {
+ let input = (v as u128) << (shift * 8);
+ let hasher = constructor(0, 0);
+ alternitives.push(hash_with(&input, hasher));
+ }
+ assert_each_byte_differs(shift, base, alternitives);
+ }
+}
+
+///Ensures that for every bit in the output there is some value for each byte in the key that flips it.
+fn test_keys_affect_every_byte<H: Hash, T: Hasher>(item: H, constructor: impl Fn(u128, u128) -> T) {
+ let base = hash_with(&item, constructor(0, 0));
+ for shift in 0..16 {
+ let mut alternitives1 = vec![];
+ let mut alternitives2 = vec![];
+ for v in 0..256 {
+ let input = (v as u128) << (shift * 8);
+ let hasher1 = constructor(input, 0);
+ let hasher2 = constructor(0, input);
+ let h1 = hash_with(&item, hasher1);
+ let h2 = hash_with(&item, hasher2);
+ alternitives1.push(h1);
+ alternitives2.push(h2);
+ }
+ assert_each_byte_differs(shift, base, alternitives1);
+ assert_each_byte_differs(shift, base, alternitives2);
+ }
+}
+
+fn assert_each_byte_differs(num: u64, base: u64, alternitives: Vec<u64>) {
+ let mut changed_bits = 0_u64;
+ for alternitive in alternitives {
+ changed_bits |= base ^ alternitive
+ }
+ assert_eq!(core::u64::MAX, changed_bits, "Bits changed: {:x} on num: {:?}", changed_bits, num);
+}
+
+fn test_finish_is_consistent<T: Hasher>(constructor: impl Fn(u128, u128) -> T) {
+ let mut hasher = constructor(1, 2);
+ "Foo".hash(&mut hasher);
+ let a = hasher.finish();
+ let b = hasher.finish();
+ assert_eq!(a, b);
+}
+
+fn test_single_key_bit_flip<T: Hasher>(constructor: impl Fn(u128, u128) -> T) {
+ for bit in 0..128 {
+ let mut a = constructor(0, 0);
+ let mut b = constructor(0, 1 << bit);
+ let mut c = constructor(1 << bit, 0);
+ "1234".hash(&mut a);
+ "1234".hash(&mut b);
+ "1234".hash(&mut c);
+ assert_sufficiently_different(a.finish(), b.finish(), 2);
+ assert_sufficiently_different(a.finish(), c.finish(), 2);
+ assert_sufficiently_different(b.finish(), c.finish(), 2);
+ let mut a = constructor(0, 0);
+ let mut b = constructor(0, 1 << bit);
+ let mut c = constructor(1 << bit, 0);
+ "12345678".hash(&mut a);
+ "12345678".hash(&mut b);
+ "12345678".hash(&mut c);
+ assert_sufficiently_different(a.finish(), b.finish(), 2);
+ assert_sufficiently_different(a.finish(), c.finish(), 2);
+ assert_sufficiently_different(b.finish(), c.finish(), 2);
+ let mut a = constructor(0, 0);
+ let mut b = constructor(0, 1 << bit);
+ let mut c = constructor(1 << bit, 0);
+ "1234567812345678".hash(&mut a);
+ "1234567812345678".hash(&mut b);
+ "1234567812345678".hash(&mut c);
+ assert_sufficiently_different(a.finish(), b.finish(), 2);
+ assert_sufficiently_different(a.finish(), c.finish(), 2);
+ assert_sufficiently_different(b.finish(), c.finish(), 2);
+ }
+}
+
+fn test_all_bytes_matter<T: Hasher>(hasher: impl Fn() -> T) {
+ let mut item = vec![0; 256];
+ let base_hash = hash(&item, &hasher);
+ for pos in 0..256 {
+ item[pos] = 255;
+ let hash = hash(&item, &hasher);
+ assert_ne!(base_hash, hash, "Position {} did not affect output", pos);
+ item[pos] = 0;
+ }
+}
+
+fn test_no_pair_collisions<T: Hasher>(hasher: impl Fn() -> T) {
+ let base = [0_u64, 0_u64];
+ let base_hash = hash(&base, &hasher);
+ for bitpos1 in 0..64 {
+ let a = 1_u64 << bitpos1;
+ for bitpos2 in 0..bitpos1 {
+ let b = 1_u64 << bitpos2;
+ let aa = hash(&[a, a], &hasher);
+ let ab = hash(&[a, b], &hasher);
+ let ba = hash(&[b, a], &hasher);
+ let bb = hash(&[b, b], &hasher);
+ assert_sufficiently_different(base_hash, aa, 3);
+ assert_sufficiently_different(base_hash, ab, 3);
+ assert_sufficiently_different(base_hash, ba, 3);
+ assert_sufficiently_different(base_hash, bb, 3);
+ assert_sufficiently_different(aa, ab, 3);
+ assert_sufficiently_different(ab, ba, 3);
+ assert_sufficiently_different(ba, bb, 3);
+ assert_sufficiently_different(aa, ba, 3);
+ assert_sufficiently_different(ab, bb, 3);
+ assert_sufficiently_different(aa, bb, 3);
+ }
+ }
+}
+
+fn hash<H: Hash, T: Hasher>(b: &H, hash_builder: &dyn Fn() -> T) -> u64 {
+ let mut hasher = hash_builder();
+ b.hash(&mut hasher);
+ hasher.finish()
+}
+
+fn hash_with<H: Hash, T: Hasher>(b: &H, mut hasher: T) -> u64 {
+ b.hash(&mut hasher);
+ hasher.finish()
+}
+
+fn test_single_bit_flip<T: Hasher>(hasher: impl Fn() -> T) {
+ let size = 32;
+ let compare_value = hash(&0u32, &hasher);
+ for pos in 0..size {
+ let test_value = hash(&(1u32 << pos), &hasher);
+ assert_sufficiently_different(compare_value, test_value, 2);
+ }
+ let size = 64;
+ let compare_value = hash(&0u64, &hasher);
+ for pos in 0..size {
+ let test_value = hash(&(1u64 << pos), &hasher);
+ assert_sufficiently_different(compare_value, test_value, 2);
+ }
+ let size = 128;
+ let compare_value = hash(&0u128, &hasher);
+ for pos in 0..size {
+ let test_value = hash(&(1u128 << pos), &hasher);
+ dbg!(compare_value, test_value);
+ assert_sufficiently_different(compare_value, test_value, 2);
+ }
+}
+
+fn test_padding_doesnot_collide<T: Hasher>(hasher: impl Fn() -> T) {
+ for c in 0..128u8 {
+ for string in ["", "\0", "\x01", "1234", "12345678", "1234567812345678"].iter() {
+ let mut short = hasher();
+ string.hash(&mut short);
+ let value = short.finish();
+ let mut padded = string.to_string();
+ for num in 1..=128 {
+ let mut long = hasher();
+ padded.push(c as char);
+ padded.hash(&mut long);
+ let (same_bytes, same_nibbles) = count_same_bytes_and_nibbles(value, long.finish());
+ assert!(
+ same_bytes <= 3,
+ "{} bytes of {} -> {:x} vs {:x}", num, c, value, long.finish()
+ );
+ assert!(
+ same_nibbles <= 8,
+ "{} bytes of {} -> {:x} vs {:x}", num, c, value, long.finish()
+ );
+ let flipped_bits = (value ^ long.finish()).count_ones();
+ assert!(flipped_bits > 10);
+ }
+ if string.len() > 0 {
+ let mut padded = string[1..].to_string();
+ padded.push(c as char);
+ for num in 2..=128 {
+ let mut long = hasher();
+ padded.push(c as char);
+ padded.hash(&mut long);
+ let (same_bytes, same_nibbles) = count_same_bytes_and_nibbles(value, long.finish());
+ assert!(
+ same_bytes <= 3,
+ "string {:?} + {} bytes of {} -> {:x} vs {:x}",
+ string,
+ num,
+ c,
+ value,
+ long.finish()
+ );
+ assert!(
+ same_nibbles <= 8,
+ "string {:?} + {} bytes of {} -> {:x} vs {:x}",
+ string,
+ num,
+ c,
+ value,
+ long.finish()
+ );
+ let flipped_bits = (value ^ long.finish()).count_ones();
+ assert!(flipped_bits > 10);
+ }
+ }
+ }
+ }
+}
+
+fn test_length_extension<T: Hasher>(hasher: impl Fn(u128, u128) -> T) {
+ for key in 0..256 {
+ let h1 = hasher(key, key);
+ let v1 = hash_with(&[0_u8, 0, 0, 0, 0, 0, 0, 0], h1);
+ let h2 = hasher(key, key);
+ let v2 = hash_with(&[1_u8, 0, 0, 0, 0, 0, 0, 0, 0], h2);
+ assert_ne!(v1, v2);
+ }
+}
+
+#[cfg(test)]
+mod fallback_tests {
+ use crate::fallback_hash::*;
+ use crate::hash_quality_test::*;
+
+ #[test]
+ fn fallback_single_bit_flip() {
+ test_single_bit_flip(|| AHasher::new_with_keys(0, 0))
+ }
+
+ #[test]
+ fn fallback_single_key_bit_flip() {
+ test_single_key_bit_flip(AHasher::new_with_keys)
+ }
+
+ #[test]
+ fn fallback_all_bytes_matter() {
+ test_all_bytes_matter(|| AHasher::new_with_keys(0, 0));
+ }
+
+ #[test]
+ fn fallback_test_no_pair_collisions() {
+ test_no_pair_collisions(|| AHasher::new_with_keys(0, 0));
+ }
+
+ #[test]
+ fn fallback_test_no_full_collisions() {
+ test_no_full_collisions(|| AHasher::new_with_keys(0, 0));
+ }
+
+ #[test]
+ fn fallback_keys_change_output() {
+ test_keys_change_output(AHasher::new_with_keys);
+ }
+
+ #[test]
+ fn fallback_input_affect_every_byte() {
+ test_input_affect_every_byte(AHasher::new_with_keys);
+ }
+
+ #[test]
+ fn fallback_keys_affect_every_byte() {
+ //For fallback second key is not used in every hash.
+ #[cfg(all(not(feature = "specialize"), feature = "folded_multiply"))]
+ test_keys_affect_every_byte(0, |a, b| AHasher::new_with_keys(a ^ b, a));
+ test_keys_affect_every_byte("", |a, b| AHasher::new_with_keys(a ^ b, a));
+ test_keys_affect_every_byte((0, 0), |a, b| AHasher::new_with_keys(a ^ b, a));
+ }
+
+ #[test]
+ fn fallback_finish_is_consistant() {
+ test_finish_is_consistent(AHasher::test_with_keys)
+ }
+
+ #[test]
+ fn fallback_padding_doesnot_collide() {
+ test_padding_doesnot_collide(|| AHasher::new_with_keys(0, 0));
+ test_padding_doesnot_collide(|| AHasher::new_with_keys(0, 2));
+ test_padding_doesnot_collide(|| AHasher::new_with_keys(2, 0));
+ test_padding_doesnot_collide(|| AHasher::new_with_keys(2, 2));
+ }
+
+ #[test]
+ fn fallback_length_extension() {
+ test_length_extension(|a, b| AHasher::new_with_keys(a, b));
+ }
+}
+
+///Basic sanity tests of the cypto properties of aHash.
+#[cfg(any(
+ all(any(target_arch = "x86", target_arch = "x86_64"), target_feature = "aes", not(miri)),
+ all(any(target_arch = "arm", target_arch = "aarch64"), target_feature = "crypto", not(miri), feature = "stdsimd")
+))]
+#[cfg(test)]
+mod aes_tests {
+ use crate::aes_hash::*;
+ use crate::hash_quality_test::*;
+ use std::hash::{Hash, Hasher};
+
+ //This encrypts to 0.
+ const BAD_KEY2: u128 = 0x6363_6363_6363_6363_6363_6363_6363_6363;
+ //This decrypts to 0.
+ const BAD_KEY: u128 = 0x5252_5252_5252_5252_5252_5252_5252_5252;
+
+ #[test]
+ fn test_single_bit_in_byte() {
+ let mut hasher1 = AHasher::test_with_keys(0, 0);
+ 8_u32.hash(&mut hasher1);
+ let mut hasher2 = AHasher::test_with_keys(0, 0);
+ 0_u32.hash(&mut hasher2);
+ assert_sufficiently_different(hasher1.finish(), hasher2.finish(), 1);
+ }
+
+ #[test]
+ fn aes_single_bit_flip() {
+ test_single_bit_flip(|| AHasher::test_with_keys(BAD_KEY, BAD_KEY));
+ test_single_bit_flip(|| AHasher::test_with_keys(BAD_KEY2, BAD_KEY2));
+ }
+
+ #[test]
+ fn aes_single_key_bit_flip() {
+ test_single_key_bit_flip(AHasher::test_with_keys)
+ }
+
+ #[test]
+ fn aes_all_bytes_matter() {
+ test_all_bytes_matter(|| AHasher::test_with_keys(BAD_KEY, BAD_KEY));
+ test_all_bytes_matter(|| AHasher::test_with_keys(BAD_KEY2, BAD_KEY2));
+ }
+
+ #[test]
+ fn aes_test_no_pair_collisions() {
+ test_no_pair_collisions(|| AHasher::test_with_keys(BAD_KEY, BAD_KEY));
+ test_no_pair_collisions(|| AHasher::test_with_keys(BAD_KEY2, BAD_KEY2));
+ }
+
+ #[test]
+ fn ase_test_no_full_collisions() {
+ test_no_full_collisions(|| AHasher::test_with_keys(12345, 67890));
+ }
+
+ #[test]
+ fn aes_keys_change_output() {
+ test_keys_change_output(AHasher::test_with_keys);
+ }
+
+ #[test]
+ fn aes_input_affect_every_byte() {
+ test_input_affect_every_byte(AHasher::test_with_keys);
+ }
+
+ #[test]
+ fn aes_keys_affect_every_byte() {
+ #[cfg(not(feature = "specialize"))]
+ test_keys_affect_every_byte(0, AHasher::test_with_keys);
+ test_keys_affect_every_byte("", AHasher::test_with_keys);
+ test_keys_affect_every_byte((0, 0), AHasher::test_with_keys);
+ }
+
+ #[test]
+ fn aes_finish_is_consistant() {
+ test_finish_is_consistent(AHasher::test_with_keys)
+ }
+
+ #[test]
+ fn aes_padding_doesnot_collide() {
+ test_padding_doesnot_collide(|| AHasher::test_with_keys(BAD_KEY, BAD_KEY));
+ test_padding_doesnot_collide(|| AHasher::test_with_keys(BAD_KEY2, BAD_KEY2));
+ }
+
+ #[test]
+ fn aes_length_extension() {
+ test_length_extension(|a, b| AHasher::test_with_keys(a, b));
+ }
+}