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tarcieri merged 1 commit into from
Mar 18, 2022
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aes: implement Zeroize for aes keys #310

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5 changes: 3 additions & 2 deletions Cargo.lock
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2 changes: 1 addition & 1 deletion aes/Cargo.toml
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Original file line numberDiff line numberDiff line change
Expand Up@@ -15,6 +15,7 @@ categories = ["cryptography", "no-std"]
[dependencies]
cfg-if = "1"
cipher = "0.4.2"
zeroize = { version = "1.5.4", optional = true, default_features = false }

[target.'cfg(any(target_arch = "aarch64", target_arch = "x86_64", target_arch = "x86"))'.dependencies]
cpufeatures = "0.2"
Expand All@@ -25,7 +26,6 @@ hex-literal = "0.3"

[features]
hazmat = [] # Expose cryptographically hazardous APIs
zeroize = ["cipher/zeroize"]

[package.metadata.docs.rs]
all-features = true
Expand Down
25 changes: 25 additions & 0 deletions aes/src/armv8.rs
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Original file line numberDiff line numberDiff line change
Expand Up@@ -122,6 +122,9 @@ macro_rules! define_aes_impl {
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name {}

#[doc=$doc]
#[doc = "block cipher (encrypt-only)"]
#[derive(Clone)]
Expand DownExpand Up@@ -172,6 +175,17 @@ macro_rules! define_aes_impl {
}
}

impl Drop for $name_enc {
#[inline]
fn drop(&mut self) {

@newpavlovnewpavlovMar 18, 2022•
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It could be worth to add #[inline] attribute here and in other Drop impls. Otherwise, without LTO Rust will not be able to inline it.

Also, are we sure that Rust always handles empty Drop impls in the same way as unimplemented Drop? I vaguely remember that Rust has a special handling of Drop-free types.

Personally, I think that having a Drop impl gated on zeroize is fine (I've used such approach in other crates), especially if we will use doc_cfg to expose it in docs.

@aticuaticuMar 18, 2022

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As far as I'm aware the only difference between implementing Drop and not implementing it is being able to implement Copy. The reference also does not seem to say much more about that.

The only other differences I could think of are performance issues, such as not having to track drop flags and not running an empty destructor (though inlining should prevent that). I added the inline attribute to all drop functions now.

In general I agree with @tarcieri that conditionally implementing Drop (or any trait) based on a not obviously related feature could lead to problems.

@tarcieritarcieriMar 18, 2022•
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If nothing else the bounds are different, although whether Drop bounds should be used/allowed at all is a matter of debate. Nevertheless, they do.

The other major difference is it's not possible to move fields out of a struct which impls Drop, although that's not happening in the current implementation so it's not a major issue.

I think Drop is magical enough conditionally dropping based on whether or not features are impl'd is a bit weird.

#[cfg(feature = "zeroize")]
zeroize::Zeroize::zeroize(&mut self.round_keys);
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name_enc {}

#[doc=$doc]
#[doc = "block cipher (decrypt-only)"]
#[derive(Clone)]
Expand DownExpand Up@@ -235,6 +249,17 @@ macro_rules! define_aes_impl {
}
}

impl Drop for $name_dec {
#[inline]
fn drop(&mut self) {
#[cfg(feature = "zeroize")]
zeroize::Zeroize::zeroize(&mut self.round_keys);
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name_dec {}

pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down
42 changes: 42 additions & 0 deletions aes/src/autodetect.rs
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Original file line numberDiff line numberDiff line change
Expand Up@@ -180,6 +180,20 @@ macro_rules! define_aes_impl {
}
}

impl Drop for $name {
#[inline]
fn drop(&mut self) {
if self.token.get() {
unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
} else {
unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
};
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name {}

#[doc=$doc]
#[doc = "block cipher (encrypt-only)"]
pub struct $name_enc {
Expand DownExpand Up@@ -266,6 +280,20 @@ macro_rules! define_aes_impl {
}
}

impl Drop for $name_enc {
#[inline]
fn drop(&mut self) {
if self.token.get() {
unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
} else {
unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
};
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name_enc {}

#[doc=$doc]
#[doc = "block cipher (decrypt-only)"]
pub struct $name_dec {
Expand DownExpand Up@@ -380,6 +408,20 @@ macro_rules! define_aes_impl {
f.write_str(stringify!($name_dec))
}
}

impl Drop for $name_dec {
#[inline]
fn drop(&mut self) {
if self.token.get() {
unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
} else {
unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
};
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name_dec {}
};
}

Expand Down
74 changes: 74 additions & 0 deletions aes/src/lib.rs
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Original file line numberDiff line numberDiff line change
Expand Up@@ -159,3 +159,77 @@ use cipher::{
pub type Block = GenericArray<u8, U16>;
/// Eight 128-bit AES blocks
pub type Block8 = GenericArray<Block, U8>;

#[cfg(test)]
mod tests {
#[cfg(feature = "zeroize")]
#[test]
fn zeroize_works() {
use super::soft;

fn test_for<T: zeroize::ZeroizeOnDrop>(val: T) {
use core::mem::{size_of, ManuallyDrop};

let mut val = ManuallyDrop::new(val);
let ptr = &val as *const _ as *const u8;
let len = size_of::<ManuallyDrop<T>>();

unsafe { ManuallyDrop::drop(&mut val) };

let slice = unsafe { core::slice::from_raw_parts(ptr, len) };

assert!(slice.iter().all(|&byte| byte == 0));
}

let key_128 = [42; 16].into();
let key_192 = [42; 24].into();
let key_256 = [42; 32].into();

use cipher::KeyInit as _;
test_for(soft::Aes128::new(&key_128));
test_for(soft::Aes128Enc::new(&key_128));
test_for(soft::Aes128Dec::new(&key_128));
test_for(soft::Aes192::new(&key_192));
test_for(soft::Aes192Enc::new(&key_192));
test_for(soft::Aes192Dec::new(&key_192));
test_for(soft::Aes256::new(&key_256));
test_for(soft::Aes256Enc::new(&key_256));
test_for(soft::Aes256Dec::new(&key_256));

#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(aes_force_soft)))]
{
use super::ni;

cpufeatures::new!(aes_intrinsics, "aes");
if aes_intrinsics::get() {
test_for(ni::Aes128::new(&key_128));
test_for(ni::Aes128Enc::new(&key_128));
test_for(ni::Aes128Dec::new(&key_128));
test_for(ni::Aes192::new(&key_192));
test_for(ni::Aes192Enc::new(&key_192));
test_for(ni::Aes192Dec::new(&key_192));
test_for(ni::Aes256::new(&key_256));
test_for(ni::Aes256Enc::new(&key_256));
test_for(ni::Aes256Dec::new(&key_256));
}
}

#[cfg(all(target_arch = "aarch64", aes_armv8, not(aes_force_soft)))]
{
use super::armv8;

cpufeatures::new!(aes_intrinsics, "aes");
if aes_intrinsics::get() {
test_for(armv8::Aes128::new(&key_128));
test_for(armv8::Aes128Enc::new(&key_128));
test_for(armv8::Aes128Dec::new(&key_128));
test_for(armv8::Aes192::new(&key_192));
test_for(armv8::Aes192Enc::new(&key_192));
test_for(armv8::Aes192Dec::new(&key_192));
test_for(armv8::Aes256::new(&key_256));
test_for(armv8::Aes256Enc::new(&key_256));
test_for(armv8::Aes256Dec::new(&key_256));
}
}
}
}
25 changes: 25 additions & 0 deletions aes/src/ni.rs
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Original file line numberDiff line numberDiff line change
Expand Up@@ -133,6 +133,9 @@ macro_rules! define_aes_impl {
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name {}

#[doc=$doc]
#[doc = "block cipher (encrypt-only)"]
#[derive(Clone)]
Expand DownExpand Up@@ -185,6 +188,17 @@ macro_rules! define_aes_impl {
}
}

impl Drop for $name_enc {
#[inline]
fn drop(&mut self) {
#[cfg(feature = "zeroize")]
zeroize::Zeroize::zeroize(&mut self.round_keys);
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name_enc {}

#[doc=$doc]
#[doc = "block cipher (decrypt-only)"]
#[derive(Clone)]
Expand DownExpand Up@@ -248,6 +262,17 @@ macro_rules! define_aes_impl {
}
}

impl Drop for $name_dec {
#[inline]
fn drop(&mut self) {
#[cfg(feature = "zeroize")]
zeroize::Zeroize::zeroize(&mut self.round_keys);
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name_dec {}

pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down
17 changes: 17 additions & 0 deletions aes/src/soft.rs
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Original file line numberDiff line numberDiff line change
Expand Up@@ -112,6 +112,17 @@ macro_rules! define_aes_impl {
}
}

impl Drop for $name {
#[inline]
fn drop(&mut self) {
#[cfg(feature = "zeroize")]
zeroize::Zeroize::zeroize(&mut self.keys);
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name {}

#[doc=$doc]
#[doc = "block cipher (encrypt-only)"]
#[derive(Clone)]
Expand DownExpand Up@@ -162,6 +173,9 @@ macro_rules! define_aes_impl {
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name_enc {}

#[doc=$doc]
#[doc = "block cipher (decrypt-only)"]
#[derive(Clone)]
Expand DownExpand Up@@ -228,6 +242,9 @@ macro_rules! define_aes_impl {
}
}

#[cfg(feature = "zeroize")]
impl zeroize::ZeroizeOnDrop for $name_dec {}

pub(crate) struct $name_back_enc<'a>(&'a $name);

impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down
, 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
 blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
btn.onclick = function() {
navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
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});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
aes: implement `Zeroize` for aes keys by aticu · Pull Request #310 · RustCrypto/block-ciphers · GitHub
Skip to content
aes: implement Zeroize for aes keys#310

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to your account

 Merged

tarcieri
merged 1 commit into

from

Mar 18, 2022
 Merged


aes: implement Zeroize for aes keys
#310
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5 changes: 3 additions & 2 deletions
Cargo.lock

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2 changes: 1 addition & 1 deletion
aes/Cargo.toml

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Original file line numberDiff line numberDiff line change
Expand Up@@ -15,6 +15,7 @@ categories = ["cryptography", "no-std"]
[dependencies]
cfg-if = "1"
cipher = "0.4.2"
zeroize = { version = "1.5.4", optional = true, default_features = false }

[target.'cfg(any(target_arch = "aarch64", target_arch = "x86_64", target_arch = "x86"))'.dependencies]
cpufeatures = "0.2"
Expand All@@ -25,7 +26,6 @@ hex-literal = "0.3"

[features]
hazmat = [] # Expose cryptographically hazardous APIs
zeroize = ["cipher/zeroize"]

[package.metadata.docs.rs]
all-features = true
Expand Down

25 changes: 25 additions & 0 deletions
aes/src/armv8.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -122,6 +122,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -172,6 +175,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
@newpavlovnewpavlovMar 18, 2022•

edited

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It could be worth to add #[inline] attribute here and in other Drop impls. Otherwise, without LTO Rust will not be able to inline it.
Also, are we sure that Rust always handles empty Drop impls in the same way as unimplemented Drop? I vaguely remember that Rust has a special handling of Drop-free types.
Personally, I think that having a Drop impl gated on zeroize is fine (I've used such approach in other crates), especially if we will use doc_cfg to expose it in docs.
@aticuaticuMar 18, 2022

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As far as I'm aware the only difference between implementing Drop and not implementing it is being able to implement Copy. The reference also does not seem to say much more about that.
The only other differences I could think of are performance issues, such as not having to track drop flags and not running an empty destructor (though inlining should prevent that). I added the inline attribute to all drop functions now.
In general I agree with @tarcieri that conditionally implementing Drop (or any trait) based on a not obviously related feature could lead to problems.
@tarcieritarcieriMar 18, 2022•

edited

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If nothing else the bounds are different, although whether Drop bounds should be used/allowed at all is a matter of debate. Nevertheless, they do.
The other major difference is it's not possible to move fields out of a struct which impls Drop, although that's not happening in the current implementation so it's not a major issue.
I think Drop is magical enough conditionally dropping based on whether or not features are impl'd is a bit weird.
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -235,6 +249,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

42 changes: 42 additions & 0 deletions
aes/src/autodetect.rs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -180,6 +180,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 pub struct $name_enc {
Expand DownExpand Up@@ -266,6 +280,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 pub struct $name_dec {
Expand DownExpand Up@@ -380,6 +408,20 @@ macro_rules! define_aes_impl {
 f.write_str(stringify!($name_dec))
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}
 };
}

Expand Down

74 changes: 74 additions & 0 deletions
aes/src/lib.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -159,3 +159,77 @@ use cipher::{
pub type Block = GenericArray<u8, U16>;
/// Eight 128-bit AES blocks
pub type Block8 = GenericArray<Block, U8>;

#[cfg(test)]
mod tests {
 #[cfg(feature = "zeroize")]
 #[test]
 fn zeroize_works() {
 use super::soft;

 fn test_for<T: zeroize::ZeroizeOnDrop>(val: T) {
 use core::mem::{size_of, ManuallyDrop};

 let mut val = ManuallyDrop::new(val);
 let ptr = &val as *const _ as *const u8;
 let len = size_of::<ManuallyDrop<T>>();

 unsafe { ManuallyDrop::drop(&mut val) };

 let slice = unsafe { core::slice::from_raw_parts(ptr, len) };

 assert!(slice.iter().all(|&byte| byte == 0));
 }

 let key_128 = [42; 16].into();
 let key_192 = [42; 24].into();
 let key_256 = [42; 32].into();

 use cipher::KeyInit as _;
 test_for(soft::Aes128::new(&key_128));
 test_for(soft::Aes128Enc::new(&key_128));
 test_for(soft::Aes128Dec::new(&key_128));
 test_for(soft::Aes192::new(&key_192));
 test_for(soft::Aes192Enc::new(&key_192));
 test_for(soft::Aes192Dec::new(&key_192));
 test_for(soft::Aes256::new(&key_256));
 test_for(soft::Aes256Enc::new(&key_256));
 test_for(soft::Aes256Dec::new(&key_256));

 #[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(aes_force_soft)))]
 {
 use super::ni;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(ni::Aes128::new(&key_128));
 test_for(ni::Aes128Enc::new(&key_128));
 test_for(ni::Aes128Dec::new(&key_128));
 test_for(ni::Aes192::new(&key_192));
 test_for(ni::Aes192Enc::new(&key_192));
 test_for(ni::Aes192Dec::new(&key_192));
 test_for(ni::Aes256::new(&key_256));
 test_for(ni::Aes256Enc::new(&key_256));
 test_for(ni::Aes256Dec::new(&key_256));
 }
 }

 #[cfg(all(target_arch = "aarch64", aes_armv8, not(aes_force_soft)))]
 {
 use super::armv8;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(armv8::Aes128::new(&key_128));
 test_for(armv8::Aes128Enc::new(&key_128));
 test_for(armv8::Aes128Dec::new(&key_128));
 test_for(armv8::Aes192::new(&key_192));
 test_for(armv8::Aes192Enc::new(&key_192));
 test_for(armv8::Aes192Dec::new(&key_192));
 test_for(armv8::Aes256::new(&key_256));
 test_for(armv8::Aes256Enc::new(&key_256));
 test_for(armv8::Aes256Dec::new(&key_256));
 }
 }
 }
}

25 changes: 25 additions & 0 deletions
aes/src/ni.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -133,6 +133,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -185,6 +188,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -248,6 +262,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

17 changes: 17 additions & 0 deletions
aes/src/soft.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -112,6 +112,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -162,6 +173,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -228,6 +242,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

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aes: implement `Zeroize` for aes keys by aticu · Pull Request #310 · RustCrypto/block-ciphers · GitHub
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aes: implement Zeroize for aes keys#310

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aes: implement Zeroize for aes keys
#310
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5 changes: 3 additions & 2 deletions
Cargo.lock

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2 changes: 1 addition & 1 deletion
aes/Cargo.toml

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Original file line numberDiff line numberDiff line change
Expand Up@@ -15,6 +15,7 @@ categories = ["cryptography", "no-std"]
[dependencies]
cfg-if = "1"
cipher = "0.4.2"
zeroize = { version = "1.5.4", optional = true, default_features = false }

[target.'cfg(any(target_arch = "aarch64", target_arch = "x86_64", target_arch = "x86"))'.dependencies]
cpufeatures = "0.2"
Expand All@@ -25,7 +26,6 @@ hex-literal = "0.3"

[features]
hazmat = [] # Expose cryptographically hazardous APIs
zeroize = ["cipher/zeroize"]

[package.metadata.docs.rs]
all-features = true
Expand Down

25 changes: 25 additions & 0 deletions
aes/src/armv8.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -122,6 +122,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -172,6 +175,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
@newpavlovnewpavlovMar 18, 2022•

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It could be worth to add #[inline] attribute here and in other Drop impls. Otherwise, without LTO Rust will not be able to inline it.
Also, are we sure that Rust always handles empty Drop impls in the same way as unimplemented Drop? I vaguely remember that Rust has a special handling of Drop-free types.
Personally, I think that having a Drop impl gated on zeroize is fine (I've used such approach in other crates), especially if we will use doc_cfg to expose it in docs.
@aticuaticuMar 18, 2022

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As far as I'm aware the only difference between implementing Drop and not implementing it is being able to implement Copy. The reference also does not seem to say much more about that.
The only other differences I could think of are performance issues, such as not having to track drop flags and not running an empty destructor (though inlining should prevent that). I added the inline attribute to all drop functions now.
In general I agree with @tarcieri that conditionally implementing Drop (or any trait) based on a not obviously related feature could lead to problems.
@tarcieritarcieriMar 18, 2022•

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If nothing else the bounds are different, although whether Drop bounds should be used/allowed at all is a matter of debate. Nevertheless, they do.
The other major difference is it's not possible to move fields out of a struct which impls Drop, although that's not happening in the current implementation so it's not a major issue.
I think Drop is magical enough conditionally dropping based on whether or not features are impl'd is a bit weird.
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -235,6 +249,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

42 changes: 42 additions & 0 deletions
aes/src/autodetect.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -180,6 +180,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 pub struct $name_enc {
Expand DownExpand Up@@ -266,6 +280,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 pub struct $name_dec {
Expand DownExpand Up@@ -380,6 +408,20 @@ macro_rules! define_aes_impl {
 f.write_str(stringify!($name_dec))
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}
 };
}

Expand Down

74 changes: 74 additions & 0 deletions
aes/src/lib.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -159,3 +159,77 @@ use cipher::{
pub type Block = GenericArray<u8, U16>;
/// Eight 128-bit AES blocks
pub type Block8 = GenericArray<Block, U8>;

#[cfg(test)]
mod tests {
 #[cfg(feature = "zeroize")]
 #[test]
 fn zeroize_works() {
 use super::soft;

 fn test_for<T: zeroize::ZeroizeOnDrop>(val: T) {
 use core::mem::{size_of, ManuallyDrop};

 let mut val = ManuallyDrop::new(val);
 let ptr = &val as *const _ as *const u8;
 let len = size_of::<ManuallyDrop<T>>();

 unsafe { ManuallyDrop::drop(&mut val) };

 let slice = unsafe { core::slice::from_raw_parts(ptr, len) };

 assert!(slice.iter().all(|&byte| byte == 0));
 }

 let key_128 = [42; 16].into();
 let key_192 = [42; 24].into();
 let key_256 = [42; 32].into();

 use cipher::KeyInit as _;
 test_for(soft::Aes128::new(&key_128));
 test_for(soft::Aes128Enc::new(&key_128));
 test_for(soft::Aes128Dec::new(&key_128));
 test_for(soft::Aes192::new(&key_192));
 test_for(soft::Aes192Enc::new(&key_192));
 test_for(soft::Aes192Dec::new(&key_192));
 test_for(soft::Aes256::new(&key_256));
 test_for(soft::Aes256Enc::new(&key_256));
 test_for(soft::Aes256Dec::new(&key_256));

 #[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(aes_force_soft)))]
 {
 use super::ni;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(ni::Aes128::new(&key_128));
 test_for(ni::Aes128Enc::new(&key_128));
 test_for(ni::Aes128Dec::new(&key_128));
 test_for(ni::Aes192::new(&key_192));
 test_for(ni::Aes192Enc::new(&key_192));
 test_for(ni::Aes192Dec::new(&key_192));
 test_for(ni::Aes256::new(&key_256));
 test_for(ni::Aes256Enc::new(&key_256));
 test_for(ni::Aes256Dec::new(&key_256));
 }
 }

 #[cfg(all(target_arch = "aarch64", aes_armv8, not(aes_force_soft)))]
 {
 use super::armv8;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(armv8::Aes128::new(&key_128));
 test_for(armv8::Aes128Enc::new(&key_128));
 test_for(armv8::Aes128Dec::new(&key_128));
 test_for(armv8::Aes192::new(&key_192));
 test_for(armv8::Aes192Enc::new(&key_192));
 test_for(armv8::Aes192Dec::new(&key_192));
 test_for(armv8::Aes256::new(&key_256));
 test_for(armv8::Aes256Enc::new(&key_256));
 test_for(armv8::Aes256Dec::new(&key_256));
 }
 }
 }
}

25 changes: 25 additions & 0 deletions
aes/src/ni.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -133,6 +133,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -185,6 +188,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -248,6 +262,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

17 changes: 17 additions & 0 deletions
aes/src/soft.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -112,6 +112,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -162,6 +173,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -228,6 +242,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

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})();
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try {
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var __re = new RegExp('^' + ".*" + '
aes: implement `Zeroize` for aes keys by aticu · Pull Request #310 · RustCrypto/block-ciphers · GitHub
Skip to content
aes: implement Zeroize for aes keys#310

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 Merged

tarcieri
merged 1 commit into

from

Mar 18, 2022
 Merged


aes: implement Zeroize for aes keys
#310
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5 changes: 3 additions & 2 deletions
Cargo.lock

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2 changes: 1 addition & 1 deletion
aes/Cargo.toml

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Original file line numberDiff line numberDiff line change
Expand Up@@ -15,6 +15,7 @@ categories = ["cryptography", "no-std"]
[dependencies]
cfg-if = "1"
cipher = "0.4.2"
zeroize = { version = "1.5.4", optional = true, default_features = false }

[target.'cfg(any(target_arch = "aarch64", target_arch = "x86_64", target_arch = "x86"))'.dependencies]
cpufeatures = "0.2"
Expand All@@ -25,7 +26,6 @@ hex-literal = "0.3"

[features]
hazmat = [] # Expose cryptographically hazardous APIs
zeroize = ["cipher/zeroize"]

[package.metadata.docs.rs]
all-features = true
Expand Down

25 changes: 25 additions & 0 deletions
aes/src/armv8.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -122,6 +122,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -172,6 +175,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
@newpavlovnewpavlovMar 18, 2022•

edited

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It could be worth to add #[inline] attribute here and in other Drop impls. Otherwise, without LTO Rust will not be able to inline it.
Also, are we sure that Rust always handles empty Drop impls in the same way as unimplemented Drop? I vaguely remember that Rust has a special handling of Drop-free types.
Personally, I think that having a Drop impl gated on zeroize is fine (I've used such approach in other crates), especially if we will use doc_cfg to expose it in docs.
@aticuaticuMar 18, 2022

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As far as I'm aware the only difference between implementing Drop and not implementing it is being able to implement Copy. The reference also does not seem to say much more about that.
The only other differences I could think of are performance issues, such as not having to track drop flags and not running an empty destructor (though inlining should prevent that). I added the inline attribute to all drop functions now.
In general I agree with @tarcieri that conditionally implementing Drop (or any trait) based on a not obviously related feature could lead to problems.
@tarcieritarcieriMar 18, 2022•

edited

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If nothing else the bounds are different, although whether Drop bounds should be used/allowed at all is a matter of debate. Nevertheless, they do.
The other major difference is it's not possible to move fields out of a struct which impls Drop, although that's not happening in the current implementation so it's not a major issue.
I think Drop is magical enough conditionally dropping based on whether or not features are impl'd is a bit weird.
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -235,6 +249,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

42 changes: 42 additions & 0 deletions
aes/src/autodetect.rs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -180,6 +180,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 pub struct $name_enc {
Expand DownExpand Up@@ -266,6 +280,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 pub struct $name_dec {
Expand DownExpand Up@@ -380,6 +408,20 @@ macro_rules! define_aes_impl {
 f.write_str(stringify!($name_dec))
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}
 };
}

Expand Down

74 changes: 74 additions & 0 deletions
aes/src/lib.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -159,3 +159,77 @@ use cipher::{
pub type Block = GenericArray<u8, U16>;
/// Eight 128-bit AES blocks
pub type Block8 = GenericArray<Block, U8>;

#[cfg(test)]
mod tests {
 #[cfg(feature = "zeroize")]
 #[test]
 fn zeroize_works() {
 use super::soft;

 fn test_for<T: zeroize::ZeroizeOnDrop>(val: T) {
 use core::mem::{size_of, ManuallyDrop};

 let mut val = ManuallyDrop::new(val);
 let ptr = &val as *const _ as *const u8;
 let len = size_of::<ManuallyDrop<T>>();

 unsafe { ManuallyDrop::drop(&mut val) };

 let slice = unsafe { core::slice::from_raw_parts(ptr, len) };

 assert!(slice.iter().all(|&byte| byte == 0));
 }

 let key_128 = [42; 16].into();
 let key_192 = [42; 24].into();
 let key_256 = [42; 32].into();

 use cipher::KeyInit as _;
 test_for(soft::Aes128::new(&key_128));
 test_for(soft::Aes128Enc::new(&key_128));
 test_for(soft::Aes128Dec::new(&key_128));
 test_for(soft::Aes192::new(&key_192));
 test_for(soft::Aes192Enc::new(&key_192));
 test_for(soft::Aes192Dec::new(&key_192));
 test_for(soft::Aes256::new(&key_256));
 test_for(soft::Aes256Enc::new(&key_256));
 test_for(soft::Aes256Dec::new(&key_256));

 #[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(aes_force_soft)))]
 {
 use super::ni;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(ni::Aes128::new(&key_128));
 test_for(ni::Aes128Enc::new(&key_128));
 test_for(ni::Aes128Dec::new(&key_128));
 test_for(ni::Aes192::new(&key_192));
 test_for(ni::Aes192Enc::new(&key_192));
 test_for(ni::Aes192Dec::new(&key_192));
 test_for(ni::Aes256::new(&key_256));
 test_for(ni::Aes256Enc::new(&key_256));
 test_for(ni::Aes256Dec::new(&key_256));
 }
 }

 #[cfg(all(target_arch = "aarch64", aes_armv8, not(aes_force_soft)))]
 {
 use super::armv8;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(armv8::Aes128::new(&key_128));
 test_for(armv8::Aes128Enc::new(&key_128));
 test_for(armv8::Aes128Dec::new(&key_128));
 test_for(armv8::Aes192::new(&key_192));
 test_for(armv8::Aes192Enc::new(&key_192));
 test_for(armv8::Aes192Dec::new(&key_192));
 test_for(armv8::Aes256::new(&key_256));
 test_for(armv8::Aes256Enc::new(&key_256));
 test_for(armv8::Aes256Dec::new(&key_256));
 }
 }
 }
}

25 changes: 25 additions & 0 deletions
aes/src/ni.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -133,6 +133,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -185,6 +188,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -248,6 +262,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

17 changes: 17 additions & 0 deletions
aes/src/soft.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -112,6 +112,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -162,6 +173,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -228,6 +242,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
aes: implement `Zeroize` for aes keys by aticu · Pull Request #310 · RustCrypto/block-ciphers · GitHub
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aes: implement Zeroize for aes keys#310

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tarcieri
merged 1 commit into

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Mar 18, 2022
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aes: implement Zeroize for aes keys
#310
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5 changes: 3 additions & 2 deletions
Cargo.lock

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2 changes: 1 addition & 1 deletion
aes/Cargo.toml

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -15,6 +15,7 @@ categories = ["cryptography", "no-std"]
[dependencies]
cfg-if = "1"
cipher = "0.4.2"
zeroize = { version = "1.5.4", optional = true, default_features = false }

[target.'cfg(any(target_arch = "aarch64", target_arch = "x86_64", target_arch = "x86"))'.dependencies]
cpufeatures = "0.2"
Expand All@@ -25,7 +26,6 @@ hex-literal = "0.3"

[features]
hazmat = [] # Expose cryptographically hazardous APIs
zeroize = ["cipher/zeroize"]

[package.metadata.docs.rs]
all-features = true
Expand Down

25 changes: 25 additions & 0 deletions
aes/src/armv8.rs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -122,6 +122,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -172,6 +175,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
@newpavlovnewpavlovMar 18, 2022•

edited

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It could be worth to add #[inline] attribute here and in other Drop impls. Otherwise, without LTO Rust will not be able to inline it.
Also, are we sure that Rust always handles empty Drop impls in the same way as unimplemented Drop? I vaguely remember that Rust has a special handling of Drop-free types.
Personally, I think that having a Drop impl gated on zeroize is fine (I've used such approach in other crates), especially if we will use doc_cfg to expose it in docs.
@aticuaticuMar 18, 2022

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As far as I'm aware the only difference between implementing Drop and not implementing it is being able to implement Copy. The reference also does not seem to say much more about that.
The only other differences I could think of are performance issues, such as not having to track drop flags and not running an empty destructor (though inlining should prevent that). I added the inline attribute to all drop functions now.
In general I agree with @tarcieri that conditionally implementing Drop (or any trait) based on a not obviously related feature could lead to problems.
@tarcieritarcieriMar 18, 2022•

edited

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If nothing else the bounds are different, although whether Drop bounds should be used/allowed at all is a matter of debate. Nevertheless, they do.
The other major difference is it's not possible to move fields out of a struct which impls Drop, although that's not happening in the current implementation so it's not a major issue.
I think Drop is magical enough conditionally dropping based on whether or not features are impl'd is a bit weird.
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -235,6 +249,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

42 changes: 42 additions & 0 deletions
aes/src/autodetect.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -180,6 +180,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 pub struct $name_enc {
Expand DownExpand Up@@ -266,6 +280,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 pub struct $name_dec {
Expand DownExpand Up@@ -380,6 +408,20 @@ macro_rules! define_aes_impl {
 f.write_str(stringify!($name_dec))
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}
 };
}

Expand Down

74 changes: 74 additions & 0 deletions
aes/src/lib.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -159,3 +159,77 @@ use cipher::{
pub type Block = GenericArray<u8, U16>;
/// Eight 128-bit AES blocks
pub type Block8 = GenericArray<Block, U8>;

#[cfg(test)]
mod tests {
 #[cfg(feature = "zeroize")]
 #[test]
 fn zeroize_works() {
 use super::soft;

 fn test_for<T: zeroize::ZeroizeOnDrop>(val: T) {
 use core::mem::{size_of, ManuallyDrop};

 let mut val = ManuallyDrop::new(val);
 let ptr = &val as *const _ as *const u8;
 let len = size_of::<ManuallyDrop<T>>();

 unsafe { ManuallyDrop::drop(&mut val) };

 let slice = unsafe { core::slice::from_raw_parts(ptr, len) };

 assert!(slice.iter().all(|&byte| byte == 0));
 }

 let key_128 = [42; 16].into();
 let key_192 = [42; 24].into();
 let key_256 = [42; 32].into();

 use cipher::KeyInit as _;
 test_for(soft::Aes128::new(&key_128));
 test_for(soft::Aes128Enc::new(&key_128));
 test_for(soft::Aes128Dec::new(&key_128));
 test_for(soft::Aes192::new(&key_192));
 test_for(soft::Aes192Enc::new(&key_192));
 test_for(soft::Aes192Dec::new(&key_192));
 test_for(soft::Aes256::new(&key_256));
 test_for(soft::Aes256Enc::new(&key_256));
 test_for(soft::Aes256Dec::new(&key_256));

 #[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(aes_force_soft)))]
 {
 use super::ni;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(ni::Aes128::new(&key_128));
 test_for(ni::Aes128Enc::new(&key_128));
 test_for(ni::Aes128Dec::new(&key_128));
 test_for(ni::Aes192::new(&key_192));
 test_for(ni::Aes192Enc::new(&key_192));
 test_for(ni::Aes192Dec::new(&key_192));
 test_for(ni::Aes256::new(&key_256));
 test_for(ni::Aes256Enc::new(&key_256));
 test_for(ni::Aes256Dec::new(&key_256));
 }
 }

 #[cfg(all(target_arch = "aarch64", aes_armv8, not(aes_force_soft)))]
 {
 use super::armv8;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(armv8::Aes128::new(&key_128));
 test_for(armv8::Aes128Enc::new(&key_128));
 test_for(armv8::Aes128Dec::new(&key_128));
 test_for(armv8::Aes192::new(&key_192));
 test_for(armv8::Aes192Enc::new(&key_192));
 test_for(armv8::Aes192Dec::new(&key_192));
 test_for(armv8::Aes256::new(&key_256));
 test_for(armv8::Aes256Enc::new(&key_256));
 test_for(armv8::Aes256Dec::new(&key_256));
 }
 }
 }
}

25 changes: 25 additions & 0 deletions
aes/src/ni.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -133,6 +133,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -185,6 +188,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -248,6 +262,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

17 changes: 17 additions & 0 deletions
aes/src/soft.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -112,6 +112,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -162,6 +173,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -228,6 +242,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
aes: implement `Zeroize` for aes keys by aticu · Pull Request #310 · RustCrypto/block-ciphers · GitHub
Skip to content
aes: implement Zeroize for aes keys#310

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

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privacy statement. We’ll occasionally send you account related emails.

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to your account

 Merged

tarcieri
merged 1 commit into

from

Mar 18, 2022
 Merged


aes: implement Zeroize for aes keys
#310
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5 changes: 3 additions & 2 deletions
Cargo.lock

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Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.


2 changes: 1 addition & 1 deletion
aes/Cargo.toml

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -15,6 +15,7 @@ categories = ["cryptography", "no-std"]
[dependencies]
cfg-if = "1"
cipher = "0.4.2"
zeroize = { version = "1.5.4", optional = true, default_features = false }

[target.'cfg(any(target_arch = "aarch64", target_arch = "x86_64", target_arch = "x86"))'.dependencies]
cpufeatures = "0.2"
Expand All@@ -25,7 +26,6 @@ hex-literal = "0.3"

[features]
hazmat = [] # Expose cryptographically hazardous APIs
zeroize = ["cipher/zeroize"]

[package.metadata.docs.rs]
all-features = true
Expand Down

25 changes: 25 additions & 0 deletions
aes/src/armv8.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -122,6 +122,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -172,6 +175,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
@newpavlovnewpavlovMar 18, 2022•

edited

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It could be worth to add #[inline] attribute here and in other Drop impls. Otherwise, without LTO Rust will not be able to inline it.
Also, are we sure that Rust always handles empty Drop impls in the same way as unimplemented Drop? I vaguely remember that Rust has a special handling of Drop-free types.
Personally, I think that having a Drop impl gated on zeroize is fine (I've used such approach in other crates), especially if we will use doc_cfg to expose it in docs.
@aticuaticuMar 18, 2022

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ContributorAuthor
Choose a reason for hiding this comment

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As far as I'm aware the only difference between implementing Drop and not implementing it is being able to implement Copy. The reference also does not seem to say much more about that.
The only other differences I could think of are performance issues, such as not having to track drop flags and not running an empty destructor (though inlining should prevent that). I added the inline attribute to all drop functions now.
In general I agree with @tarcieri that conditionally implementing Drop (or any trait) based on a not obviously related feature could lead to problems.
@tarcieritarcieriMar 18, 2022•

edited

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Member
Choose a reason for hiding this comment

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If nothing else the bounds are different, although whether Drop bounds should be used/allowed at all is a matter of debate. Nevertheless, they do.
The other major difference is it's not possible to move fields out of a struct which impls Drop, although that's not happening in the current implementation so it's not a major issue.
I think Drop is magical enough conditionally dropping based on whether or not features are impl'd is a bit weird.
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -235,6 +249,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

42 changes: 42 additions & 0 deletions
aes/src/autodetect.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -180,6 +180,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 pub struct $name_enc {
Expand DownExpand Up@@ -266,6 +280,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 pub struct $name_dec {
Expand DownExpand Up@@ -380,6 +408,20 @@ macro_rules! define_aes_impl {
 f.write_str(stringify!($name_dec))
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}
 };
}

Expand Down

74 changes: 74 additions & 0 deletions
aes/src/lib.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -159,3 +159,77 @@ use cipher::{
pub type Block = GenericArray<u8, U16>;
/// Eight 128-bit AES blocks
pub type Block8 = GenericArray<Block, U8>;

#[cfg(test)]
mod tests {
 #[cfg(feature = "zeroize")]
 #[test]
 fn zeroize_works() {
 use super::soft;

 fn test_for<T: zeroize::ZeroizeOnDrop>(val: T) {
 use core::mem::{size_of, ManuallyDrop};

 let mut val = ManuallyDrop::new(val);
 let ptr = &val as *const _ as *const u8;
 let len = size_of::<ManuallyDrop<T>>();

 unsafe { ManuallyDrop::drop(&mut val) };

 let slice = unsafe { core::slice::from_raw_parts(ptr, len) };

 assert!(slice.iter().all(|&byte| byte == 0));
 }

 let key_128 = [42; 16].into();
 let key_192 = [42; 24].into();
 let key_256 = [42; 32].into();

 use cipher::KeyInit as _;
 test_for(soft::Aes128::new(&key_128));
 test_for(soft::Aes128Enc::new(&key_128));
 test_for(soft::Aes128Dec::new(&key_128));
 test_for(soft::Aes192::new(&key_192));
 test_for(soft::Aes192Enc::new(&key_192));
 test_for(soft::Aes192Dec::new(&key_192));
 test_for(soft::Aes256::new(&key_256));
 test_for(soft::Aes256Enc::new(&key_256));
 test_for(soft::Aes256Dec::new(&key_256));

 #[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(aes_force_soft)))]
 {
 use super::ni;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(ni::Aes128::new(&key_128));
 test_for(ni::Aes128Enc::new(&key_128));
 test_for(ni::Aes128Dec::new(&key_128));
 test_for(ni::Aes192::new(&key_192));
 test_for(ni::Aes192Enc::new(&key_192));
 test_for(ni::Aes192Dec::new(&key_192));
 test_for(ni::Aes256::new(&key_256));
 test_for(ni::Aes256Enc::new(&key_256));
 test_for(ni::Aes256Dec::new(&key_256));
 }
 }

 #[cfg(all(target_arch = "aarch64", aes_armv8, not(aes_force_soft)))]
 {
 use super::armv8;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(armv8::Aes128::new(&key_128));
 test_for(armv8::Aes128Enc::new(&key_128));
 test_for(armv8::Aes128Dec::new(&key_128));
 test_for(armv8::Aes192::new(&key_192));
 test_for(armv8::Aes192Enc::new(&key_192));
 test_for(armv8::Aes192Dec::new(&key_192));
 test_for(armv8::Aes256::new(&key_256));
 test_for(armv8::Aes256Enc::new(&key_256));
 test_for(armv8::Aes256Dec::new(&key_256));
 }
 }
 }
}

25 changes: 25 additions & 0 deletions
aes/src/ni.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -133,6 +133,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -185,6 +188,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -248,6 +262,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

17 changes: 17 additions & 0 deletions
aes/src/soft.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -112,6 +112,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -162,6 +173,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -228,6 +242,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
aes: implement `Zeroize` for aes keys by aticu · Pull Request #310 · RustCrypto/block-ciphers · GitHub
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aes: implement Zeroize for aes keys#310

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tarcieri
merged 1 commit into

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Mar 18, 2022
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aes: implement Zeroize for aes keys
#310
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5 changes: 3 additions & 2 deletions
Cargo.lock

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2 changes: 1 addition & 1 deletion
aes/Cargo.toml

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Original file line numberDiff line numberDiff line change
Expand Up@@ -15,6 +15,7 @@ categories = ["cryptography", "no-std"]
[dependencies]
cfg-if = "1"
cipher = "0.4.2"
zeroize = { version = "1.5.4", optional = true, default_features = false }

[target.'cfg(any(target_arch = "aarch64", target_arch = "x86_64", target_arch = "x86"))'.dependencies]
cpufeatures = "0.2"
Expand All@@ -25,7 +26,6 @@ hex-literal = "0.3"

[features]
hazmat = [] # Expose cryptographically hazardous APIs
zeroize = ["cipher/zeroize"]

[package.metadata.docs.rs]
all-features = true
Expand Down

25 changes: 25 additions & 0 deletions
aes/src/armv8.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -122,6 +122,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -172,6 +175,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
@newpavlovnewpavlovMar 18, 2022•

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It could be worth to add #[inline] attribute here and in other Drop impls. Otherwise, without LTO Rust will not be able to inline it.
Also, are we sure that Rust always handles empty Drop impls in the same way as unimplemented Drop? I vaguely remember that Rust has a special handling of Drop-free types.
Personally, I think that having a Drop impl gated on zeroize is fine (I've used such approach in other crates), especially if we will use doc_cfg to expose it in docs.
@aticuaticuMar 18, 2022

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As far as I'm aware the only difference between implementing Drop and not implementing it is being able to implement Copy. The reference also does not seem to say much more about that.
The only other differences I could think of are performance issues, such as not having to track drop flags and not running an empty destructor (though inlining should prevent that). I added the inline attribute to all drop functions now.
In general I agree with @tarcieri that conditionally implementing Drop (or any trait) based on a not obviously related feature could lead to problems.
@tarcieritarcieriMar 18, 2022•

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If nothing else the bounds are different, although whether Drop bounds should be used/allowed at all is a matter of debate. Nevertheless, they do.
The other major difference is it's not possible to move fields out of a struct which impls Drop, although that's not happening in the current implementation so it's not a major issue.
I think Drop is magical enough conditionally dropping based on whether or not features are impl'd is a bit weird.
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -235,6 +249,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

42 changes: 42 additions & 0 deletions
aes/src/autodetect.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -180,6 +180,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 pub struct $name_enc {
Expand DownExpand Up@@ -266,6 +280,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 pub struct $name_dec {
Expand DownExpand Up@@ -380,6 +408,20 @@ macro_rules! define_aes_impl {
 f.write_str(stringify!($name_dec))
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}
 };
}

Expand Down

74 changes: 74 additions & 0 deletions
aes/src/lib.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -159,3 +159,77 @@ use cipher::{
pub type Block = GenericArray<u8, U16>;
/// Eight 128-bit AES blocks
pub type Block8 = GenericArray<Block, U8>;

#[cfg(test)]
mod tests {
 #[cfg(feature = "zeroize")]
 #[test]
 fn zeroize_works() {
 use super::soft;

 fn test_for<T: zeroize::ZeroizeOnDrop>(val: T) {
 use core::mem::{size_of, ManuallyDrop};

 let mut val = ManuallyDrop::new(val);
 let ptr = &val as *const _ as *const u8;
 let len = size_of::<ManuallyDrop<T>>();

 unsafe { ManuallyDrop::drop(&mut val) };

 let slice = unsafe { core::slice::from_raw_parts(ptr, len) };

 assert!(slice.iter().all(|&byte| byte == 0));
 }

 let key_128 = [42; 16].into();
 let key_192 = [42; 24].into();
 let key_256 = [42; 32].into();

 use cipher::KeyInit as _;
 test_for(soft::Aes128::new(&key_128));
 test_for(soft::Aes128Enc::new(&key_128));
 test_for(soft::Aes128Dec::new(&key_128));
 test_for(soft::Aes192::new(&key_192));
 test_for(soft::Aes192Enc::new(&key_192));
 test_for(soft::Aes192Dec::new(&key_192));
 test_for(soft::Aes256::new(&key_256));
 test_for(soft::Aes256Enc::new(&key_256));
 test_for(soft::Aes256Dec::new(&key_256));

 #[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(aes_force_soft)))]
 {
 use super::ni;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(ni::Aes128::new(&key_128));
 test_for(ni::Aes128Enc::new(&key_128));
 test_for(ni::Aes128Dec::new(&key_128));
 test_for(ni::Aes192::new(&key_192));
 test_for(ni::Aes192Enc::new(&key_192));
 test_for(ni::Aes192Dec::new(&key_192));
 test_for(ni::Aes256::new(&key_256));
 test_for(ni::Aes256Enc::new(&key_256));
 test_for(ni::Aes256Dec::new(&key_256));
 }
 }

 #[cfg(all(target_arch = "aarch64", aes_armv8, not(aes_force_soft)))]
 {
 use super::armv8;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(armv8::Aes128::new(&key_128));
 test_for(armv8::Aes128Enc::new(&key_128));
 test_for(armv8::Aes128Dec::new(&key_128));
 test_for(armv8::Aes192::new(&key_192));
 test_for(armv8::Aes192Enc::new(&key_192));
 test_for(armv8::Aes192Dec::new(&key_192));
 test_for(armv8::Aes256::new(&key_256));
 test_for(armv8::Aes256Enc::new(&key_256));
 test_for(armv8::Aes256Dec::new(&key_256));
 }
 }
 }
}

25 changes: 25 additions & 0 deletions
aes/src/ni.rs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -133,6 +133,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -185,6 +188,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -248,6 +262,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

17 changes: 17 additions & 0 deletions
aes/src/soft.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -112,6 +112,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -162,6 +173,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -228,6 +242,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
aes: implement `Zeroize` for aes keys by aticu · Pull Request #310 · RustCrypto/block-ciphers · GitHub
Skip to content
aes: implement Zeroize for aes keys#310

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 Merged

tarcieri
merged 1 commit into

from

Mar 18, 2022
 Merged


aes: implement Zeroize for aes keys
#310
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5 changes: 3 additions & 2 deletions
Cargo.lock

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2 changes: 1 addition & 1 deletion
aes/Cargo.toml

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Original file line numberDiff line numberDiff line change
Expand Up@@ -15,6 +15,7 @@ categories = ["cryptography", "no-std"]
[dependencies]
cfg-if = "1"
cipher = "0.4.2"
zeroize = { version = "1.5.4", optional = true, default_features = false }

[target.'cfg(any(target_arch = "aarch64", target_arch = "x86_64", target_arch = "x86"))'.dependencies]
cpufeatures = "0.2"
Expand All@@ -25,7 +26,6 @@ hex-literal = "0.3"

[features]
hazmat = [] # Expose cryptographically hazardous APIs
zeroize = ["cipher/zeroize"]

[package.metadata.docs.rs]
all-features = true
Expand Down

25 changes: 25 additions & 0 deletions
aes/src/armv8.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -122,6 +122,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -172,6 +175,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
@newpavlovnewpavlovMar 18, 2022•

edited

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It could be worth to add #[inline] attribute here and in other Drop impls. Otherwise, without LTO Rust will not be able to inline it.
Also, are we sure that Rust always handles empty Drop impls in the same way as unimplemented Drop? I vaguely remember that Rust has a special handling of Drop-free types.
Personally, I think that having a Drop impl gated on zeroize is fine (I've used such approach in other crates), especially if we will use doc_cfg to expose it in docs.
@aticuaticuMar 18, 2022

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As far as I'm aware the only difference between implementing Drop and not implementing it is being able to implement Copy. The reference also does not seem to say much more about that.
The only other differences I could think of are performance issues, such as not having to track drop flags and not running an empty destructor (though inlining should prevent that). I added the inline attribute to all drop functions now.
In general I agree with @tarcieri that conditionally implementing Drop (or any trait) based on a not obviously related feature could lead to problems.
@tarcieritarcieriMar 18, 2022•

edited

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If nothing else the bounds are different, although whether Drop bounds should be used/allowed at all is a matter of debate. Nevertheless, they do.
The other major difference is it's not possible to move fields out of a struct which impls Drop, although that's not happening in the current implementation so it's not a major issue.
I think Drop is magical enough conditionally dropping based on whether or not features are impl'd is a bit weird.
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -235,6 +249,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

42 changes: 42 additions & 0 deletions
aes/src/autodetect.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -180,6 +180,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 pub struct $name_enc {
Expand DownExpand Up@@ -266,6 +280,20 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 pub struct $name_dec {
Expand DownExpand Up@@ -380,6 +408,20 @@ macro_rules! define_aes_impl {
 f.write_str(stringify!($name_dec))
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 if self.token.get() {
 unsafe { ManuallyDrop::drop(&mut self.inner.intrinsics) };
 } else {
 unsafe { ManuallyDrop::drop(&mut self.inner.soft) };
 };
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}
 };
}

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74 changes: 74 additions & 0 deletions
aes/src/lib.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -159,3 +159,77 @@ use cipher::{
pub type Block = GenericArray<u8, U16>;
/// Eight 128-bit AES blocks
pub type Block8 = GenericArray<Block, U8>;

#[cfg(test)]
mod tests {
 #[cfg(feature = "zeroize")]
 #[test]
 fn zeroize_works() {
 use super::soft;

 fn test_for<T: zeroize::ZeroizeOnDrop>(val: T) {
 use core::mem::{size_of, ManuallyDrop};

 let mut val = ManuallyDrop::new(val);
 let ptr = &val as *const _ as *const u8;
 let len = size_of::<ManuallyDrop<T>>();

 unsafe { ManuallyDrop::drop(&mut val) };

 let slice = unsafe { core::slice::from_raw_parts(ptr, len) };

 assert!(slice.iter().all(|&byte| byte == 0));
 }

 let key_128 = [42; 16].into();
 let key_192 = [42; 24].into();
 let key_256 = [42; 32].into();

 use cipher::KeyInit as _;
 test_for(soft::Aes128::new(&key_128));
 test_for(soft::Aes128Enc::new(&key_128));
 test_for(soft::Aes128Dec::new(&key_128));
 test_for(soft::Aes192::new(&key_192));
 test_for(soft::Aes192Enc::new(&key_192));
 test_for(soft::Aes192Dec::new(&key_192));
 test_for(soft::Aes256::new(&key_256));
 test_for(soft::Aes256Enc::new(&key_256));
 test_for(soft::Aes256Dec::new(&key_256));

 #[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(aes_force_soft)))]
 {
 use super::ni;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(ni::Aes128::new(&key_128));
 test_for(ni::Aes128Enc::new(&key_128));
 test_for(ni::Aes128Dec::new(&key_128));
 test_for(ni::Aes192::new(&key_192));
 test_for(ni::Aes192Enc::new(&key_192));
 test_for(ni::Aes192Dec::new(&key_192));
 test_for(ni::Aes256::new(&key_256));
 test_for(ni::Aes256Enc::new(&key_256));
 test_for(ni::Aes256Dec::new(&key_256));
 }
 }

 #[cfg(all(target_arch = "aarch64", aes_armv8, not(aes_force_soft)))]
 {
 use super::armv8;

 cpufeatures::new!(aes_intrinsics, "aes");
 if aes_intrinsics::get() {
 test_for(armv8::Aes128::new(&key_128));
 test_for(armv8::Aes128Enc::new(&key_128));
 test_for(armv8::Aes128Dec::new(&key_128));
 test_for(armv8::Aes192::new(&key_192));
 test_for(armv8::Aes192Enc::new(&key_192));
 test_for(armv8::Aes192Dec::new(&key_192));
 test_for(armv8::Aes256::new(&key_256));
 test_for(armv8::Aes256Enc::new(&key_256));
 test_for(armv8::Aes256Dec::new(&key_256));
 }
 }
 }
}

25 changes: 25 additions & 0 deletions
aes/src/ni.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -133,6 +133,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -185,6 +188,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_enc {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -248,6 +262,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name_dec {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.round_keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name_enc);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down

17 changes: 17 additions & 0 deletions
aes/src/soft.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -112,6 +112,17 @@ macro_rules! define_aes_impl {
 }
 }

 impl Drop for $name {
 #[inline]
 fn drop(&mut self) {
 #[cfg(feature = "zeroize")]
 zeroize::Zeroize::zeroize(&mut self.keys);
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name {}

 #[doc=$doc]
 #[doc = "block cipher (encrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -162,6 +173,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_enc {}

 #[doc=$doc]
 #[doc = "block cipher (decrypt-only)"]
 #[derive(Clone)]
Expand DownExpand Up@@ -228,6 +242,9 @@ macro_rules! define_aes_impl {
 }
 }

 #[cfg(feature = "zeroize")]
 impl zeroize::ZeroizeOnDrop for $name_dec {}

 pub(crate) struct $name_back_enc<'a>(&'a $name);

 impl<'a> BlockSizeUser for $name_back_enc<'a> {
Expand Down