laron_crypto/
aes.rs

1// This file is part of the laron-crypto
2//
3// Copyright 2023 Ade M Ramdani
4//
5// This program is free software: you can redistribute it and/or modify
6// it under the terms of the GNU General Public License as published by
7// the Free Software Foundation, either version 3 of the License, or
8// (at your option) any later version.
9//
10// This program is distributed in the hope that it will be useful,
11// but WITHOUT ANY WARRANTY; without even the implied warranty of
12// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13// GNU General Public License for more details.
14//
15// You should have received a copy of the GNU General Public License
16// along with this program.  If not, see <https://www.gnu.org/licenses/>.
17
18use aes_gcm::{aead::Aead, Aes256Gcm, KeyInit, Nonce};
19use rand::RngCore;
20
21use crate::{
22    error::{Error, Result},
23    PrivateKey,
24};
25
26/// Aes trait provides the interface for AES encryption and
27/// decryption.
28pub trait Aes {
29    /// Encrypt the given string.
30    fn encrypt(&self, data: &str) -> String;
31
32    /// Encrypt with the given nonce.
33    fn encrypt_with_nonce(&self, data: &str, nonce: &str) -> Result<String>;
34
35    /// Decrypt the given string.
36    fn decrypt(&self, data: &str) -> Result<String>;
37
38    ///  Decrypt with the given nonce.
39    fn decrypt_with_nonce(&self, data: &str, nonce: &str) -> Result<String>;
40}
41
42impl From<&PrivateKey> for Aes256Gcm {
43    fn from(value: &PrivateKey) -> Self {
44        Self::new_from_slice(value.as_slice()).unwrap()
45    }
46}
47
48impl Aes for PrivateKey {
49    fn encrypt(&self, data: &str) -> String {
50        let mut nonce_bytes = [0u8; 12];
51        rand::thread_rng().fill_bytes(&mut nonce_bytes);
52        let nonce = Nonce::from_slice(&nonce_bytes);
53        let key: Aes256Gcm = self.into();
54        let ciphertext = key.encrypt(nonce, data.as_bytes()).unwrap();
55        let mut result = vec![];
56        result.extend_from_slice(&nonce_bytes);
57        result.extend_from_slice(&ciphertext);
58        hex::encode(result)
59    }
60
61    fn encrypt_with_nonce(&self, data: &str, nonce: &str) -> Result<String> {
62        let nonce = Nonce::from_slice(nonce.as_bytes());
63        let key: Aes256Gcm = self.into();
64        let ciphertext = key
65            .encrypt(nonce, data.as_bytes())
66            .map_err(|e| Error::EncryptError(e.to_string()))?;
67        Ok(hex::encode(ciphertext))
68    }
69
70    fn decrypt(&self, data: &str) -> Result<String> {
71        let data = hex::decode(data)?;
72        if data.len() < 12 {
73            return Err(Error::LengthError(
74                "Encrypted data is too short".to_string(),
75            ));
76        }
77        let nonce = Nonce::from_slice(&data[0..12]);
78        let key: Aes256Gcm = self.into();
79        let plaintext = key
80            .decrypt(nonce, &data[12..])
81            .map_err(|e| Error::DecryptError(e.to_string()))?;
82        Ok(String::from_utf8(plaintext).unwrap())
83    }
84
85    fn decrypt_with_nonce(&self, data: &str, nonce: &str) -> Result<String> {
86        let data = hex::decode(data)?;
87        let nonce = Nonce::from_slice(nonce.as_bytes());
88        let key: Aes256Gcm = self.into();
89        let plaintext = key
90            .decrypt(nonce, data.as_ref())
91            .map_err(|e| Error::DecryptError(e.to_string()))?;
92        Ok(String::from_utf8(plaintext).unwrap())
93    }
94}
95
96#[cfg(test)]
97mod tests {
98    use super::*;
99
100    #[test]
101    fn test_aes() {
102        let text = "Hello World!";
103        let key = PrivateKey::new();
104        let encrypted = key.encrypt(text);
105        let decrypted = key.decrypt(&encrypted).unwrap();
106        assert_eq!(text, decrypted);
107        let nonce = "unique nonce";
108        let encrypted = key.encrypt_with_nonce(text, nonce).unwrap();
109        let decrypted = key.decrypt_with_nonce(&encrypted, nonce).unwrap();
110        assert_eq!(text, decrypted);
111    }
112}
laron_crypto/aes.rs

laron_crypto/
aes.rs
