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magic_crypt/ciphers/
aes256.rs

1use alloc::vec::Vec;
2#[cfg(feature = "std")]
3use std::io::{Read, Write};
4
5#[cfg(feature = "std")]
6use aes::cipher::{
7    array::ArraySize,
8    typenum::{IsGreaterOrEqual, PartialDiv, True, U16},
9};
10use aes::{
11    Aes256,
12    cipher::{
13        BlockModeDecrypt, BlockModeEncrypt, Iv, Key, KeyIvInit, array::Array, block_padding::Pkcs7,
14    },
15};
16use md5::{Digest, Md5};
17use sha2::Sha256;
18
19#[cfg(feature = "std")]
20use crate::functions::{
21    decrypt_reader_to_writer as decrypt_stream, encrypt_reader_to_writer as encrypt_stream,
22    to_blocks,
23};
24use crate::{MagicCryptError, MagicCryptTrait};
25
26type Aes256CbcEnc = cbc::Encryptor<Aes256>;
27type Aes256CbcDec = cbc::Decryptor<Aes256>;
28
29#[cfg(feature = "std")]
30const BLOCK_SIZE: usize = 16;
31
32/// This struct can help you encrypt or decrypt data via AES-256 in a quick way.
33#[derive(Clone)]
34pub struct MagicCrypt256 {
35    key: Key<Aes256CbcEnc>,
36    iv:  Iv<Aes256CbcEnc>,
37}
38
39impl_cipher_secret_traits!(MagicCrypt256);
40
41impl MagicCryptTrait for MagicCrypt256 {
42    fn new<S: AsRef<[u8]>, V: AsRef<[u8]>>(key: S, iv: Option<V>) -> MagicCrypt256 {
43        let iv = match iv {
44            Some(s) => {
45                let mut hasher = Md5::new();
46                hasher.update(s.as_ref());
47
48                hasher.finalize()
49            },
50            None => Array::default(),
51        };
52
53        let key = {
54            let mut hasher = Sha256::new();
55            hasher.update(key.as_ref());
56
57            hasher.finalize()
58        };
59
60        MagicCrypt256 {
61            key,
62            iv,
63        }
64    }
65
66    #[inline]
67    fn encrypt_to_bytes<T: ?Sized + AsRef<[u8]>>(&self, data: &T) -> Vec<u8> {
68        let data = data.as_ref();
69
70        let cipher = Aes256CbcEnc::new(&self.key, &self.iv);
71
72        cipher.encrypt_padded_vec::<Pkcs7>(data)
73    }
74
75    #[cfg(feature = "std")]
76    fn encrypt_reader_to_bytes(&self, reader: &mut dyn Read) -> Result<Vec<u8>, MagicCryptError> {
77        let mut final_result = Vec::new();
78
79        let data_length = reader.read_to_end(&mut final_result)?;
80
81        let padding_length = BLOCK_SIZE - (data_length % BLOCK_SIZE);
82        let final_length = data_length + padding_length;
83
84        final_result.resize(final_length, 0);
85
86        let cipher = Aes256CbcEnc::new(&self.key, &self.iv);
87
88        cipher.encrypt_padded::<Pkcs7>(&mut final_result, data_length).unwrap();
89
90        Ok(final_result)
91    }
92
93    #[cfg(feature = "std")]
94    fn encrypt_reader_to_writer2<
95        N: ArraySize + PartialDiv<U16> + IsGreaterOrEqual<U16, Output = True>,
96    >(
97        &self,
98        reader: &mut dyn Read,
99        writer: &mut dyn Write,
100    ) -> Result<(), MagicCryptError> {
101        let mut cipher = Aes256CbcEnc::new(&self.key, &self.iv);
102
103        encrypt_stream::<N>(reader, writer, BLOCK_SIZE, |buffer| {
104            cipher.encrypt_blocks(to_blocks(buffer));
105        })
106    }
107
108    #[inline]
109    fn decrypt_bytes_to_bytes<T: ?Sized + AsRef<[u8]>>(
110        &self,
111        bytes: &T,
112    ) -> Result<Vec<u8>, MagicCryptError> {
113        let bytes = bytes.as_ref();
114
115        let cipher = Aes256CbcDec::new(&self.key, &self.iv);
116
117        let final_result = cipher.decrypt_padded_vec::<Pkcs7>(bytes)?;
118
119        Ok(final_result)
120    }
121
122    #[cfg(feature = "std")]
123    fn decrypt_reader_to_bytes(&self, reader: &mut dyn Read) -> Result<Vec<u8>, MagicCryptError> {
124        let mut final_result = Vec::new();
125
126        reader.read_to_end(&mut final_result)?;
127
128        let cipher = Aes256CbcDec::new(&self.key, &self.iv);
129
130        let data_length = cipher.decrypt_padded::<Pkcs7>(&mut final_result)?.len();
131
132        final_result.truncate(data_length);
133
134        Ok(final_result)
135    }
136
137    #[cfg(feature = "std")]
138    fn decrypt_reader_to_writer2<
139        N: ArraySize + PartialDiv<U16> + IsGreaterOrEqual<U16, Output = True>,
140    >(
141        &self,
142        reader: &mut dyn Read,
143        writer: &mut dyn Write,
144    ) -> Result<(), MagicCryptError> {
145        let mut cipher = Aes256CbcDec::new(&self.key, &self.iv);
146
147        decrypt_stream::<N>(reader, writer, BLOCK_SIZE, |buffer| {
148            cipher.decrypt_blocks(to_blocks(buffer));
149        })
150    }
151}