/rust/registry/src/index.crates.io-1949cf8c6b5b557f/aws-lc-rs-1.15.4/src/buffer.rs

Source
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0 OR ISC

//! This module exposes a buffer type used in crate APIs returning private keys and other "private"
//! contents.

#![allow(clippy::module_name_repetitions)]

use alloc::borrow::Cow;
use core::fmt;
use core::marker::PhantomData;

use zeroize::Zeroize;

/// This is a buffer type for some data exposed by various APIs in this crate.
///
/// `T` acts as a discriminant between different kinds of data.
///
/// The buffer will be zeroed on drop if it is owned.
pub struct Buffer<'a, T>(Cow<'a, [u8]>, PhantomData<T>);

impl<T> Drop for Buffer<'_, T> {
    fn drop(&mut self) {
        if let Cow::Owned(b) = &mut self.0 {
            b.zeroize();
        }
    }
}

impl<'a, T> Buffer<'a, T> {
    pub(crate) fn new(owned: Vec<u8>) -> Buffer<'a, T> {
        Buffer(Cow::Owned(owned), PhantomData)
    }

    pub(crate) fn take_from_slice(slice: &mut [u8]) -> Buffer<'a, T> {
        let owned = slice.to_vec();
        slice.zeroize();
        Buffer(Cow::Owned(owned), PhantomData)
    }
}

impl<T> fmt::Debug for Buffer<'_, T> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
        f.write_str("Buffer(...)")
    }
}

impl<T> AsRef<[u8]> for Buffer<'_, T> {
    #[inline]
    fn as_ref(&self) -> &[u8] {
        self.0.as_ref()
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_new() {
        let buffer: Buffer<u8> = Buffer::new(vec![1, 2, 3]);
        assert_eq!(buffer.as_ref(), &[1, 2, 3]);
    }

    #[test]
    fn test_take_from_slice() {
        let mut slice = [1, 2, 3];
        let buffer: Buffer<u8> = Buffer::take_from_slice(&mut slice);
        assert_eq!(buffer.as_ref(), &[1, 2, 3]);
        assert_eq!(slice, [0, 0, 0]);
    }
}

Line	Count	Source
1		// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
2		// SPDX-License-Identifier: Apache-2.0 OR ISC
3
4		//! This module exposes a buffer type used in crate APIs returning private keys and other "private"
5		//! contents.
6
7		#![allow(clippy::module_name_repetitions)]
8
9		use alloc::borrow::Cow;
10		use core::fmt;
11		use core::marker::PhantomData;
12
13		use zeroize::Zeroize;
14
15		/// This is a buffer type for some data exposed by various APIs in this crate.
16		///
17		/// `T` acts as a discriminant between different kinds of data.
18		///
19		/// The buffer will be zeroed on drop if it is owned.
20		pub struct Buffer<'a, T>(Cow<'a, [u8]>, PhantomData<T>);
21
22		impl<T> Drop for Buffer<'_, T> {
23	0	fn drop(&mut self) {
24	0	if let Cow::Owned(b) = &mut self.0 {
25	0	b.zeroize();
26	0	}
27	0	}
28		}
29
30		impl<'a, T> Buffer<'a, T> {
31	0	pub(crate) fn new(owned: Vec<u8>) -> Buffer<'a, T> {
32	0	Buffer(Cow::Owned(owned), PhantomData)
33	0	} Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<aws_lc_rs::kem::buffer_type::EncapsulationKeyBytesType>>::new Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<aws_lc_rs::encoding::buffer_type::Pkcs8V1DerType>>::new Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<aws_lc_rs::encoding::buffer_type::Pkcs8V2DerType>>::new Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<aws_lc_rs::encoding::buffer_type::EcPrivateKeyBinType>>::new Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<aws_lc_rs::encoding::buffer_type::PublicKeyX509DerType>>::new Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<aws_lc_rs::encoding::buffer_type::Curve25519SeedBinType>>::new Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<aws_lc_rs::encoding::buffer_type::EcPrivateKeyRfc5915DerType>>::new Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<aws_lc_rs::encoding::buffer_type::EcPublicKeyCompressedBinType>>::new Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<aws_lc_rs::encoding::buffer_type::EcPublicKeyUncompressedBinType>>::new Unexecuted instantiation: <aws_lc_rs::buffer::Buffer<&[u8]>>::new
34
35	0	pub(crate) fn take_from_slice(slice: &mut [u8]) -> Buffer<'a, T> {
36	0	let owned = slice.to_vec();
37	0	slice.zeroize();
38	0	Buffer(Cow::Owned(owned), PhantomData)
39	0	}
40		}
41
42		impl<T> fmt::Debug for Buffer<'_, T> {
43	0	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
44	0	f.write_str("Buffer(...)")
45	0	}
46		}
47
48		impl<T> AsRef<[u8]> for Buffer<'_, T> {
49		#[inline]
50	0	fn as_ref(&self) -> &[u8] {
51	0	self.0.as_ref()
52	0	}
53		}
54
55		#[cfg(test)]
56		mod tests {
57		use super::*;
58
59		#[test]
60		fn test_new() {
61		let buffer: Buffer<u8> = Buffer::new(vec![1, 2, 3]);
62		assert_eq!(buffer.as_ref(), &[1, 2, 3]);
63		}
64
65		#[test]
66		fn test_take_from_slice() {
67		let mut slice = [1, 2, 3];
68		let buffer: Buffer<u8> = Buffer::take_from_slice(&mut slice);
69		assert_eq!(buffer.as_ref(), &[1, 2, 3]);
70		assert_eq!(slice, [0, 0, 0]);
71		}
72		}

Coverage Report

Created: 2026-02-14 06:14