1 #![cfg_attr(fuzzing, no_main)]
2 // Copyright 2022 Google LLC
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 crypto_provider_rustcrypto::RustCrypto;
17 use derive_fuzztest::fuzztest;
18 use ldt_tbc::{TweakableBlockCipherDecrypter, TweakableBlockCipherEncrypter};
19 use xts_aes::*;
20 
21 #[fuzztest]
test(data: XtsFuzzInput)22 fn test(data: XtsFuzzInput) {
23     // XTS requires at least one block
24     if data.plaintext.len() < 16 {
25         return;
26     }
27 
28     let xts_enc =
29         <XtsAes128<RustCrypto> as ldt_tbc::TweakableBlockCipher<16>>::EncryptionCipher::new(
30             &XtsAes128Key::from(&data.key),
31         );
32     let xts_dec =
33         <XtsAes128<RustCrypto> as ldt_tbc::TweakableBlockCipher<16>>::DecryptionCipher::new(
34             &XtsAes128Key::from(&data.key),
35         );
36 
37     let tweak: Tweak = data.tweak.into();
38 
39     let mut buffer = data.plaintext.clone();
40 
41     xts_enc.encrypt_data_unit(tweak.clone(), &mut buffer[..]).unwrap();
42     xts_dec.decrypt_data_unit(tweak, &mut buffer[..]).unwrap();
43     assert_eq!(data.plaintext, buffer);
44 }
45 
46 #[derive(Clone, Debug, arbitrary::Arbitrary)]
47 struct XtsFuzzInput {
48     key: [u8; 32],
49     tweak: [u8; 16],
50     // min length = AES block size
51     plaintext: Vec<u8>,
52 }
53