snarkvm_console_program/data/record/
encrypt.rs

1// Copyright (c) 2019-2025 Provable Inc.
2// This file is part of the snarkVM 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
16use super::*;
17
18impl<N: Network> Record<N, Plaintext<N>> {
19    /// Encrypts `self` for the record owner under the given randomizer.
20    pub fn encrypt(&self, randomizer: Scalar<N>) -> Result<Record<N, Ciphertext<N>>> {
21        // Output the encrypted record.
22        self.encrypt_symmetric(randomizer).map(|(encrypted_record, _)| encrypted_record)
23    }
24
25    /// Encrypts `self` for the record owner under the given randomizer,
26    /// and returns the encrypted record alongside the record view key.
27    #[allow(clippy::type_complexity)]
28    pub fn encrypt_symmetric(&self, randomizer: Scalar<N>) -> Result<(Record<N, Ciphertext<N>>, Field<N>)> {
29        // Ensure the randomizer corresponds to the record nonce.
30        if self.nonce == N::g_scalar_multiply(&randomizer) {
31            // Compute the record view key.
32            let record_view_key = (**self.owner * randomizer).to_x_coordinate();
33            // Encrypt the record.
34            let encrypted_record = self.encrypt_symmetric_unchecked(&record_view_key)?;
35            // Return the encrypted record and the record view key.
36            Ok((encrypted_record, record_view_key))
37        } else {
38            bail!("Illegal operation: Record::encrypt() randomizer does not correspond to the record nonce.")
39        }
40    }
41
42    /// Encrypts `self` under the given record view key.
43    /// Note: This method does not check that the record view key corresponds to the record owner.
44    /// Use `Self::encrypt` for the checked variant.
45    pub fn encrypt_symmetric_unchecked(&self, record_view_key: &Field<N>) -> Result<Record<N, Ciphertext<N>>> {
46        // Determine the number of randomizers needed to encrypt the record.
47        let num_randomizers = self.num_randomizers()?;
48        // Prepare a randomizer for each field element.
49        let randomizers = N::hash_many_psd8(&[N::encryption_domain(), *record_view_key], num_randomizers);
50        // Encrypt the record.
51        self.encrypt_with_randomizers(&randomizers)
52    }
53
54    /// Encrypts `self` under the given randomizers.
55    fn encrypt_with_randomizers(&self, randomizers: &[Field<N>]) -> Result<Record<N, Ciphertext<N>>> {
56        // Initialize an index to keep track of the randomizer index.
57        let mut index: usize = 0;
58
59        // Encrypt the owner.
60        let owner = match self.owner.is_public() {
61            true => self.owner.encrypt_with_randomizer(&[])?,
62            false => self.owner.encrypt_with_randomizer(&[randomizers[index]])?,
63        };
64
65        // Increment the index if the owner is private.
66        if owner.is_private() {
67            index += 1;
68        }
69
70        // Encrypt the data.
71        let mut encrypted_data = IndexMap::with_capacity(self.data.len());
72        for (id, entry, num_randomizers) in self.data.iter().map(|(id, entry)| (id, entry, entry.num_randomizers())) {
73            // Retrieve the result for `num_randomizers`.
74            let num_randomizers = num_randomizers? as usize;
75            // Retrieve the randomizers for this entry.
76            let randomizers = &randomizers[index..index + num_randomizers];
77            // Encrypt the entry.
78            let entry = match entry {
79                // Constant entries do not need to be encrypted.
80                Entry::Constant(plaintext) => Entry::Constant(plaintext.clone()),
81                // Public entries do not need to be encrypted.
82                Entry::Public(plaintext) => Entry::Public(plaintext.clone()),
83                // Private entries are encrypted with the given randomizers.
84                Entry::Private(private) => Entry::Private(Ciphertext::try_from(
85                    private
86                        .to_fields()?
87                        .iter()
88                        .zip_eq(randomizers)
89                        .map(|(plaintext, randomizer)| *plaintext + randomizer)
90                        .collect::<Vec<_>>(),
91                )?),
92            };
93            // Insert the encrypted entry.
94            if encrypted_data.insert(*id, entry).is_some() {
95                bail!("Duplicate identifier in record: {id}");
96            }
97            // Increment the index.
98            index += num_randomizers;
99        }
100
101        // Return the encrypted record.
102        Self::from_ciphertext(owner, encrypted_data, self.nonce, self.version)
103    }
104}
snarkvm_console_program/data/record/encrypt.rs

snarkvm_console_program/data/record/
encrypt.rs
