1  // Copyright (c) 2019-2025 Alpha-Delta Network Inc.
 2  // This file is part of the deltavm library.
 3  
 4  // Licensed under the Apache License, Version 2.0 (the "License");
 5  // you may not use this file except in compliance with the License.
 6  // You may obtain a copy of the License at:
 7  
 8  // http://www.apache.org/licenses/LICENSE-2.0
 9  
10  // Unless required by applicable law or agreed to in writing, software
11  // distributed under the License is distributed on an "AS IS" BASIS,
12  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  // See the License for the specific language governing permissions and
14  // limitations under the License.
15  
16  use super::*;
17  
18  impl<E: Environment, const RATE: usize> HashMany for Poseidon<E, RATE> {
19      type Input = Field<E>;
20      type Output = Field<E>;
21  
22      /// Returns the cryptographic hash for a list of field elements as input,
23      /// and returns the specified number of field elements as output.
24      #[inline]
25      fn hash_many(&self, input: &[Self::Input], num_outputs: u16) -> Vec<Self::Output> {
26          // Construct the preimage: [ DOMAIN || LENGTH(INPUT) || [0; RATE-2] || INPUT ].
27          let mut preimage = Vec::with_capacity(RATE + input.len());
28          preimage.push(self.domain);
29          preimage.push(Field::<E>::from_u128(input.len() as u128));
30          preimage.resize(RATE, Field::<E>::zero()); // Pad up to RATE.
31          preimage.extend_from_slice(input);
32  
33          let mut sponge = PoseidonSponge::<E, RATE, CAPACITY>::new(&self.parameters);
34          sponge.absorb(&preimage);
35          sponge.squeeze(num_outputs).into_vec()
36      }
37  }