Files
vnt/vnt/src/cipher/mod.rs
T

115 lines
4.4 KiB
Rust

use std::io;
use aes_gcm::{AeadInPlace, Aes128Gcm, Aes256Gcm, Key, Nonce, Tag,KeyInit};
use aes_gcm::aead::consts::{U12, U16};
use aes_gcm::aead::generic_array::GenericArray;
use sha2::Digest;
use crate::protocol;
use crate::protocol::{ip_turn_packet, NetPacket};
#[derive(Clone)]
pub enum Cipher {
AesGCM128(Aes128Gcm),
AesGCM256(Aes256Gcm),
None,
}
impl Cipher {
pub fn new(password: Option<String>) -> Self {
if let Some(password) = password {
let mut hasher = sha2::Sha256::new();
hasher.update(password.as_bytes());
let key: [u8; 32] = hasher.finalize().into();
if password.len() < 8 {
let key: &Key<Aes128Gcm> = key[..16].into();
Cipher::AesGCM128(Aes128Gcm::new(&key))
} else {
let key: &Key<Aes256Gcm> = &key.into();
Cipher::AesGCM256(Aes256Gcm::new(&key))
}
} else {
Cipher::None
}
}
pub fn decrypt_ipv4(&self, net_packet: &mut NetPacket<&mut [u8]>) -> io::Result<Option<usize>> {
match &self {
Cipher::None => {
return Ok(None);
}
_ => {}
}
if !net_packet.is_encrypt() {
//未加密的数据直接丢弃
return Err(io::Error::new(io::ErrorKind::Other, "not encrypt"));
}
if net_packet.payload().len() < 16 {
log::error!("数据异常,长度小于16");
return Err(io::Error::new(io::ErrorKind::Other, "data err"));
}
let mut nonce = [0; 12];
nonce[0..4].copy_from_slice(&net_packet.source().octets());
nonce[4..8].copy_from_slice(&net_packet.destination().octets());
nonce[8] = protocol::Protocol::IpTurn.into();
nonce[9] = ip_turn_packet::Protocol::Ipv4.into();
let nonce: &GenericArray<u8, U12> = Nonce::from_slice(&nonce);
let payload_len = net_packet.payload().len() - 16;
let tag: GenericArray<u8, U16> = Tag::clone_from_slice(&net_packet.payload()[payload_len..]);
let rs = match &self {
Cipher::AesGCM128(cipher) => {
cipher.decrypt_in_place_detached(nonce, &[], &mut net_packet.payload_mut()[..payload_len], &tag)
}
Cipher::AesGCM256(cipher) => {
cipher.decrypt_in_place_detached(nonce, &[], &mut net_packet.payload_mut()[..payload_len], &tag)
}
Cipher::None => {
return Ok(None);
}
};
if let Err(e) = rs {
return Err(io::Error::new(io::ErrorKind::Other, format!("解密失败:{}", e)));
}
return Ok(Some(payload_len));
}
/// net_packet 必须预留足够长度
/// data_len是有效载荷的长度
/// 返回加密后载荷的长度
pub fn encrypt_ipv4(&self, payload_len: usize, net_packet: &mut NetPacket<&mut [u8]>) -> io::Result<Option<usize>> {
match &self {
Cipher::None => {
return Ok(None);
}
_ => {}
}
let mut nonce = [0; 12];
nonce[0..4].copy_from_slice(&net_packet.source().octets());
nonce[4..8].copy_from_slice(&net_packet.destination().octets());
nonce[8] = protocol::Protocol::IpTurn.into();
nonce[9] = ip_turn_packet::Protocol::Ipv4.into();
let nonce: &GenericArray<u8, U12> = Nonce::from_slice(&nonce);
let rs = match &self {
Cipher::AesGCM128(cipher) => {
cipher.encrypt_in_place_detached(nonce, &[], &mut net_packet.payload_mut()[..payload_len])
}
Cipher::AesGCM256(cipher) => {
cipher.encrypt_in_place_detached(nonce, &[], &mut net_packet.payload_mut()[..payload_len])
}
Cipher::None => {
return Ok(None);
}
};
return match rs {
Ok(tag) => {
if tag.len() != 16 {
return Err(io::Error::new(io::ErrorKind::Other, format!("加密tag长度错误:{}", tag.len())));
}
net_packet.set_encrypt_flag(true);
net_packet.payload_mut()[payload_len..payload_len + 16].copy_from_slice(tag.as_slice());
Ok(Some(payload_len + 16))
}
Err(e) => {
Err(io::Error::new(io::ErrorKind::Other, format!("加密失败:{}", e)))
}
};
}
}