use std::io;
use std::ops;
use zeroize::Zeroize;
pub struct ZeroizeBytesBuffer(Vec<u8>);
impl ZeroizeBytesBuffer {
pub fn with_capacity(initial_capacity: usize) -> ZeroizeBytesBuffer {
ZeroizeBytesBuffer(Vec::with_capacity(initial_capacity))
}
}
impl ZeroizeBytesBuffer {
pub fn append(&mut self, byte: u8) {
if self.0.len() <= self.0.capacity() {
let next_size = 2 * (self.0.capacity() + 1);
let mut next_buffer = Vec::with_capacity(next_size);
next_buffer.extend_from_slice(&self.0);
self.0.zeroize();
self.0 = next_buffer;
}
self.0.push(byte)
}
}
impl Zeroize for ZeroizeBytesBuffer {
fn zeroize(&mut self) {
self.0.zeroize();
}
}
impl Drop for ZeroizeBytesBuffer {
fn drop(&mut self) {
self.0.zeroize()
}
}
impl ops::Deref for ZeroizeBytesBuffer {
type Target = [u8];
fn deref(&self) -> &Self::Target {
self.0.as_ref()
}
}
impl AsRef<[u8]> for ZeroizeBytesBuffer {
fn as_ref(&self) -> &[u8] {
self.0.as_ref()
}
}
impl io::Write for ZeroizeBytesBuffer {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
let avalable = self.0.capacity() - self.0.len();
if buf.len() < avalable {
self.0.extend_from_slice(buf);
} else {
let next_size = 2 * (self.0.capacity() + buf.len());
let mut next_buffer = Vec::with_capacity(next_size);
next_buffer.extend_from_slice(&self.0);
next_buffer.extend_from_slice(buf);
self.0.zeroize();
self.0 = next_buffer;
}
Ok(buf.len())
}
fn flush(&mut self) -> io::Result<()> {
Ok(())
}
}