starknet_os: change all encoding to le in naive blake

Author: meship-starkware

crates/apollo_starknet_os_program/src/cairo/starkware/starknet/core/os/encrypt.cairo

@@ -6,7 +6,7 @@ from starkware.cairo.common.registers import get_fp_and_pc
 from starkware.starknet.core.os.naive_blake import (
     calc_blake_hash,
     naive_encode_felt252s_to_u32s,
-    u256_to_felt,
+    felt_from_le_u32s,
     create_initial_state_for_blake2s,
     blake_with_opcode_for_single_16_length_word,
 )
@@ -197,21 +197,22 @@ func encrypt_inner{range_check_ptr, encrypted_dst: felt*}(
     assert blake_output[6] = encoded_symmetric_key[6];
     assert blake_output[7] = encoded_symmetric_key[7];
     let blake_output = &blake_output[8];
-    // Write encoded index to blake output - since index is small, manually encode as [0, 0, 0, 0, 0, 0, 0, index].
-    assert blake_output[0] = 0;
+    // Write encoded index to blake output - since index is small,
+    // manually encode in little-endian notion as [index, 0, 0, 0, 0, 0, 0, 0].
+    assert blake_output[0] = index;
     assert blake_output[1] = 0;
     assert blake_output[2] = 0;
     assert blake_output[3] = 0;
     assert blake_output[4] = 0;
     assert blake_output[5] = 0;
     assert blake_output[6] = 0;
-    assert blake_output[7] = index;
+    assert blake_output[7] = 0;
     let blake_output = &blake_output[8];
     // Calculate blake hash modulo prime.
     blake_with_opcode_for_single_16_length_word(
         data=blake_encoding_start, out=blake_output, initial_state=initial_state
     );
-    let hash = u256_to_felt(u256=blake_output);
+    let hash = felt_from_le_u32s(u256=blake_output);
     let blake_output = &blake_output[8];
 
     // Encrypt the current element.

crates/apollo_starknet_os_program/src/cairo/starkware/starknet/core/os/naive_blake.cairo

@@ -1,6 +1,14 @@
 from starkware.cairo.common.alloc import alloc
 from starkware.cairo.common.cairo_blake2s.blake2s import blake_with_opcode
 
+// Gets a felt that represent a 256-bit unsigned integer stored as an array of eight 32-bit unsigned integers
+// represented in little-endian notation. Return the felt representation of the integer modulo prime.
+func felt_from_le_u32s(u256: felt*) -> felt {
+    let hash = u256[7] * 2 ** 224 + u256[6] * 2 ** 192 + u256[5] * 2 ** 160 + u256[4] * 2 ** 128 +
+        u256[3] * 2 ** 96 + u256[2] * 2 ** 64 + u256[1] * 2 ** 32 + u256[0];
+    return hash;
+}
+
 // Computes blake2s of `input` of size 16 felts, representing 32 bits each.
 // The initial state is the standard BLAKE2s IV XORed with the parameter block P[0] = 0x01010020.
 func blake_with_opcode_for_single_16_length_word(data: felt*, out: felt*, initial_state: felt*) {
@@ -51,10 +59,9 @@ func create_initial_state_for_blake2s() -> (initial_state: felt*) {
 }
 
 // Encodes a list of felt252s to a list of u32s, each felt is mapped to eight u32s.
-// Returns the length of the resulting list of u32s.
 func naive_encode_felt252s_to_u32s(
     packed_values_len: felt, packed_values: felt*, unpacked_u32s: felt*
-) -> felt {
+) {
     alloc_locals;
 
     local end: felt* = &packed_values[packed_values_len];
@@ -65,41 +72,29 @@ func naive_encode_felt252s_to_u32s(
 
     loop:
     if (end == packed_values) {
-        return out - unpacked_u32s;
+        return ();
     }
 
     // TODO(Noa): Assert that the limbs represent a number in the range [0, PRIME-1].
     // Assert that the limbs represent the number.
-    assert packed_values[0] = (
-        (out[7] + (2 ** 32 * out[6])) +
-        2 ** (32 * 2) * (out[5] + 2 ** 32 * out[4]) +
-        2 ** (32 * 4) * (out[3] + 2 ** 32 * out[2]) +
-        2 ** (32 * 6) * (out[1] + 2 ** 32 * out[0])
-    );
+    let actual_value = felt_from_le_u32s(u256=out);
+    assert packed_values[0] = actual_value;
 
     tempvar out = &out[8];
     tempvar packed_values = &packed_values[1];
     jmp loop;
 }
 
-// Gets a felt that represent a 256-bit unsigned integer stored as an array of eight 32-bit unsigned integers
-// represented in little-endian notation. Return the felt representation of the integer modulo prime.
-func u256_to_felt(u256: felt*) -> felt {
-    let hash = u256[7] * 2 ** 224 + u256[6] * 2 ** 192 + u256[5] * 2 ** 160 + u256[4] * 2 ** 128 +
-        u256[3] * 2 ** 96 + u256[2] * 2 ** 64 + u256[1] * 2 ** 32 + u256[0];
-    return hash;
-}
-
 // / Encodes a slice of `Felt` values into 32-bit words, then hashes the resulting byte stream
 // / with Blake2s-256 and returns the 256-bit digest to a 252-bit field element `Felt`.
 func calc_blake_hash{range_check_ptr: felt}(data_len: felt, data: felt*) -> (hash: felt) {
     alloc_locals;
     let (local encoded_data: felt*) = alloc();
-    let encoded_data_len = naive_encode_felt252s_to_u32s(
+    naive_encode_felt252s_to_u32s(
         packed_values_len=data_len, packed_values=data, unpacked_u32s=encoded_data
     );
     let (local blake_output: felt*) = alloc();
-    blake_with_opcode(len=encoded_data_len, data=encoded_data, out=blake_output);
-    let hash = u256_to_felt(u256=blake_output);
+    blake_with_opcode(len=8 * data_len, data=encoded_data, out=blake_output);
+    let hash = felt_from_le_u32s(u256=blake_output);
     return (hash=hash);
 }

crates/apollo_starknet_os_program/src/program_hash.json

@@ -1,5 +1,5 @@
 {
-  "os": "0x7f1ad76d2bc6845ae61c5ccb2f8aae2e2ff1418b5572bebcdf2dd832556a6b0",
-  "aggregator": "0x31a2d2cf5b673b718d9a9ed527fc343c2744ec3bd1daf1a7b9f1a4a1fa3d21d",
-  "aggregator_with_prefix": "0x4460a2cd0996f05489f8339d50f317d07b06f26dd2ecd5a5540368d2cef2a9d"
+  "os": "0x411bcd3d0448fcf9ced52a49731e9e81ecbb52d86c862d575716b8b2c38aed1",
+  "aggregator": "0x11009a80eecd0085c7890ee149d4c837f5c08ab1f076ad2ec714bd29eb77052",
+  "aggregator_with_prefix": "0x228933088f4fd745ab9c1bee3571779d6ca2a86117fa8b5a17cabeddf01404e"
 }

crates/starknet_os/src/hints/hint_implementation/blake2s/implementation.rs

@@ -95,13 +95,12 @@ pub(crate) fn naive_unpack_felt252s_to_u32s(
     HintArgs { vm, ids_data, ap_tracking, .. }: HintArgs<'_>,
 ) -> OsHintResult {
     let (unpacked_u32s, vals) = unpack_setup(vm, ids_data, ap_tracking)?;
-
     let out: Vec<MaybeRelocatable> = vals
         .into_iter()
         .map(|val| val.to_biguint())
         .flat_map(|mut val| {
             let mut limbs = vec![BigUint::from(0_u32); 8];
-            for limb in limbs.iter_mut().rev() {
+            for limb in limbs.iter_mut() {
                 let (q, r) = val.div_rem(&POW2_32);
                 *limb = r;
                 val = q;

crates/starknet_os/src/hints/hint_implementation/state_diff_encryption/utils.rs

@@ -118,10 +118,10 @@ fn calc_blake_hash(data: &[Felt]) -> Felt {
 pub fn naive_encode_felts_to_u32s(felts: Vec<Felt>) -> Vec<u32> {
     let mut unpacked_u32s = Vec::new();
     for felt in felts {
-        let felt_as_be_bytes = felt.to_bytes_be();
-        // big: 8 limbs, big‐endian order.
-        for chunk in felt_as_be_bytes.chunks_exact(4) {
-            unpacked_u32s.push(u32::from_be_bytes(chunk.try_into().unwrap()));
+        let felt_as_le_bytes = felt.to_bytes_le();
+        // big: 8 limbs, little-endian order.
+        for chunk in felt_as_le_bytes.chunks_exact(4) {
+            unpacked_u32s.push(u32::from_le_bytes(chunk.try_into().unwrap()));
         }
     }
     unpacked_u32s