bssl_crypto/cipher/
aes_cbc.rs

1// Copyright 2023 The BoringSSL Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     https://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15extern crate alloc;
16
17use crate::cipher::{
18    BlockCipher, Cipher, CipherError, CipherInitPurpose, EvpAes128Cbc, EvpAes256Cbc,
19};
20use alloc::vec::Vec;
21
22/// AES-CBC-128 Cipher implementation.
23pub struct Aes128Cbc(Cipher<EvpAes128Cbc>);
24
25impl BlockCipher for Aes128Cbc {
26    type Key = [u8; 16];
27    type Nonce = [u8; 16];
28
29    fn new_encrypt(key: &Self::Key, nonce: &Self::Nonce) -> Self {
30        Self(Cipher::new(key, nonce, CipherInitPurpose::Encrypt))
31    }
32
33    fn new_decrypt(key: &Self::Key, nonce: &Self::Nonce) -> Self {
34        Self(Cipher::new(key, nonce, CipherInitPurpose::Decrypt))
35    }
36
37    fn encrypt_padded(self, buffer: &[u8]) -> Result<Vec<u8>, CipherError> {
38        // Note: Padding is enabled because we did not disable it with `EVP_CIPHER_CTX_set_padding`
39        self.0.encrypt(buffer)
40    }
41
42    fn decrypt_padded(self, buffer: &[u8]) -> Result<Vec<u8>, CipherError> {
43        // Note: Padding is enabled because we did not disable it with `EVP_CIPHER_CTX_set_padding`
44        self.0.decrypt(buffer)
45    }
46}
47
48/// AES-CBC-256 Cipher implementation.
49pub struct Aes256Cbc(Cipher<EvpAes256Cbc>);
50
51impl BlockCipher for Aes256Cbc {
52    type Key = [u8; 32];
53    type Nonce = [u8; 16];
54
55    fn new_encrypt(key: &Self::Key, nonce: &Self::Nonce) -> Self {
56        Self(Cipher::new(key, nonce, CipherInitPurpose::Encrypt))
57    }
58
59    fn new_decrypt(key: &Self::Key, nonce: &Self::Nonce) -> Self {
60        Self(Cipher::new(key, nonce, CipherInitPurpose::Decrypt))
61    }
62
63    fn encrypt_padded(self, buffer: &[u8]) -> Result<Vec<u8>, CipherError> {
64        // Note: Padding is enabled because we did not disable it with `EVP_CIPHER_CTX_set_padding`
65        self.0.encrypt(buffer)
66    }
67
68    fn decrypt_padded(self, buffer: &[u8]) -> Result<Vec<u8>, CipherError> {
69        // Note: Padding is enabled because we did not disable it with `EVP_CIPHER_CTX_set_padding`
70        self.0.decrypt(buffer)
71    }
72}
73
74#[allow(clippy::expect_used)]
75#[cfg(test)]
76mod test {
77    use super::*;
78    use crate::test_helpers::decode_hex;
79
80    #[test]
81    fn aes_128_cbc_test_encrypt() {
82        // https://github.com/google/wycheproof/blob/master/testvectors/aes_cbc_pkcs5_test.json#L30
83        // tcId: 2
84        let iv = decode_hex("c9ee3cd746bf208c65ca9e72a266d54f");
85        let key = decode_hex("e09eaa5a3f5e56d279d5e7a03373f6ea");
86
87        let cipher = Aes128Cbc::new_encrypt(&key, &iv);
88        let msg: [u8; 16] = decode_hex("ef4eab37181f98423e53e947e7050fd0");
89
90        let output = cipher.encrypt_padded(&msg).expect("Failed to encrypt");
91
92        let expected_ciphertext: [u8; 32] =
93            decode_hex("d1fa697f3e2e04d64f1a0da203813ca5bc226a0b1d42287b2a5b994a66eaf14a");
94        assert_eq!(expected_ciphertext, &output[..]);
95    }
96
97    #[test]
98    fn aes_128_cbc_test_encrypt_more_than_one_block() {
99        // https://github.com/google/wycheproof/blob/master/testvectors/aes_cbc_pkcs5_test.json#L210
100        // tcId: 20
101        let iv = decode_hex("54f2459e40e002763144f4752cde2fb5");
102        let key = decode_hex("831e664c9e3f0c3094c0b27b9d908eb2");
103
104        let cipher = Aes128Cbc::new_encrypt(&key, &iv);
105        let msg: [u8; 17] = decode_hex("26603bb76dd0a0180791c4ed4d3b058807");
106
107        let output = cipher.encrypt_padded(&msg).expect("Failed to encrypt");
108
109        let expected_ciphertext: [u8; 32] =
110            decode_hex("8d55dc10584e243f55d2bdbb5758b7fabcd58c8d3785f01c7e3640b2a1dadcd9");
111        assert_eq!(expected_ciphertext, &output[..]);
112    }
113
114    #[test]
115    fn aes_128_cbc_test_decrypt() {
116        // https://github.com/google/wycheproof/blob/master/testvectors/aes_cbc_pkcs5_test.json#L30
117        // tcId: 2
118        let key = decode_hex("e09eaa5a3f5e56d279d5e7a03373f6ea");
119        let iv = decode_hex("c9ee3cd746bf208c65ca9e72a266d54f");
120        let cipher = Aes128Cbc::new_decrypt(&key, &iv);
121        let ciphertext: [u8; 32] =
122            decode_hex("d1fa697f3e2e04d64f1a0da203813ca5bc226a0b1d42287b2a5b994a66eaf14a");
123        let decrypted = cipher
124            .decrypt_padded(&ciphertext)
125            .expect("Failed to decrypt");
126        let expected_plaintext: [u8; 16] = decode_hex("ef4eab37181f98423e53e947e7050fd0");
127        assert_eq!(expected_plaintext, &decrypted[..]);
128    }
129
130    #[test]
131    fn aes_128_cbc_test_decrypt_empty_message() {
132        // https://github.com/google/wycheproof/blob/master/testvectors/aes_cbc_pkcs5_test.json#L20
133        // tcId: 1
134        let key = decode_hex("e34f15c7bd819930fe9d66e0c166e61c");
135        let iv = decode_hex("da9520f7d3520277035173299388bee2");
136        let cipher = Aes128Cbc::new_decrypt(&key, &iv);
137        let ciphertext: [u8; 16] = decode_hex("b10ab60153276941361000414aed0a9d");
138        let decrypted = cipher
139            .decrypt_padded(&ciphertext)
140            .expect("Failed to decrypt");
141        let expected_plaintext: [u8; 0] = decode_hex("");
142        assert_eq!(expected_plaintext, &decrypted[..]);
143    }
144
145    #[test]
146    pub fn aes_256_cbc_test_encrypt() {
147        // https://github.com/google/wycheproof/blob/master/testvectors/aes_cbc_pkcs5_test.json#L1412
148        // tcId: 124
149        let iv = decode_hex("9ec7b863ac845cad5e4673da21f5b6a9");
150        let key = decode_hex("612e837843ceae7f61d49625faa7e7494f9253e20cb3adcea686512b043936cd");
151
152        let cipher = Aes256Cbc::new_encrypt(&key, &iv);
153        let msg: [u8; 16] = decode_hex("cc37fae15f745a2f40e2c8b192f2b38d");
154
155        let output = cipher.encrypt_padded(&msg).expect("Failed to encrypt");
156
157        let expected_ciphertext: [u8; 32] =
158            decode_hex("299295be47e9f5441fe83a7a811c4aeb2650333e681e69fa6b767d28a6ccf282");
159        assert_eq!(expected_ciphertext, &output[..]);
160    }
161
162    #[test]
163    pub fn aes_256_cbc_test_encrypt_more_than_one_block() {
164        // https://github.com/google/wycheproof/blob/master/testvectors/aes_cbc_pkcs5_test.json#L1582C24-L1582C24
165        // tcId: 141
166        let iv = decode_hex("4b74bd981ea9d074757c3e2ef515e5fb");
167        let key = decode_hex("73216fafd0022d0d6ee27198b2272578fa8f04dd9f44467fbb6437aa45641bf7");
168
169        let cipher = Aes256Cbc::new_encrypt(&key, &iv);
170        let msg: [u8; 17] = decode_hex("d5247b8f6c3edcbfb1d591d13ece23d2f5");
171
172        let output = cipher.encrypt_padded(&msg).expect("Failed to encrypt");
173
174        let expected_ciphertext: [u8; 32] =
175            decode_hex("fbea776fb1653635f88e2937ed2450ba4e9063e96d7cdba04928f01cb85492fe");
176        assert_eq!(expected_ciphertext, &output[..]);
177    }
178
179    #[test]
180    fn aes_256_cbc_test_decrypt() {
181        // https://github.com/google/wycheproof/blob/master/testvectors/aes_cbc_pkcs5_test.json#L1452
182        // tcId: 128
183        let key = decode_hex("ea3b016bdd387dd64d837c71683808f335dbdc53598a4ea8c5f952473fafaf5f");
184        let iv = decode_hex("fae3e2054113f6b3b904aadbfe59655c");
185        let cipher = Aes256Cbc::new_decrypt(&key, &iv);
186        let ciphertext: [u8; 16] = decode_hex("b90c326b72eb222ddb4dae47f2bc223c");
187        let decrypted = cipher
188            .decrypt_padded(&ciphertext)
189            .expect("Failed to decrypt");
190        let expected_plaintext: [u8; 2] = decode_hex("6601");
191        assert_eq!(expected_plaintext, &decrypted[..]);
192    }
193}
bssl_crypto/cipher/aes_cbc.rs

bssl_crypto/cipher/
aes_cbc.rs
