// Copyright 2018-2024 Brian Smith.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#![cfg(any(
all(target_arch = "aarch64", target_endian = "little"),
target_arch = "x86",
target_arch = "x86_64"
))]
use super::{Block, Counter, EncryptBlock, EncryptCtr32, Iv, KeyBytes, Overlapping, AES_KEY};
use crate::{cpu, error};
use cfg_if::cfg_if;
cfg_if! {
if #[cfg(all(target_arch = "aarch64", target_endian = "little"))] {
pub(in super::super) type RequiredCpuFeatures = cpu::arm::Aes;
pub(in super::super) type OptionalCpuFeatures = ();
} else if #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] {
use cpu::intel::{Aes, Avx, Ssse3};
// Some functions seem to have been written to require only SSE/SSE2
// but there seem to be no SSSE3-less CPUs with AES-NI, and we don't
// have feature detection for SSE2.
pub(in super::super) type RequiredCpuFeatures = (Aes, Ssse3);
pub(in super::super) type OptionalCpuFeatures = Avx;
}
}
#[derive(Clone)]
pub struct Key {
inner: AES_KEY,
}
impl Key {
#[cfg(all(target_arch = "aarch64", target_endian = "little"))]
pub(in super::super) fn new(
bytes: KeyBytes<'_>,
_required_cpu_features: RequiredCpuFeatures,
_optional_cpu_features: Option<OptionalCpuFeatures>,
) -> Result<Self, error::Unspecified> {
let inner = unsafe { set_encrypt_key!(aes_hw_set_encrypt_key, bytes) }?;
Ok(Self { inner })
}
#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
pub(in super::super) fn new(
bytes: KeyBytes<'_>,
(Aes { .. }, Ssse3 { .. }): RequiredCpuFeatures,
optional_cpu_features: Option<OptionalCpuFeatures>,
) -> Result<Self, error::Unspecified> {
// Ssse3 is required, but upstream only uses this if there is also Avx;
// presumably the base version is faster on pre-AVX CPUs.
let inner = if let Some(Avx { .. }) = optional_cpu_features {
unsafe { set_encrypt_key!(aes_hw_set_encrypt_key_alt, bytes) }?
} else {
unsafe { set_encrypt_key!(aes_hw_set_encrypt_key_base, bytes) }?
};
Ok(Self { inner })
}
#[cfg(any(
all(target_arch = "aarch64", target_endian = "little"),
target_arch = "x86_64"
))]
#[must_use]
pub(in super::super) fn inner_less_safe(&self) -> &AES_KEY {
&self.inner
}
}
impl EncryptBlock for Key {
fn encrypt_block(&self, block: Block) -> Block {
super::encrypt_block_using_encrypt_iv_xor_block(self, block)
}
fn encrypt_iv_xor_block(&self, iv: Iv, block: Block) -> Block {
super::encrypt_iv_xor_block_using_ctr32(self, iv, block)
}
}
impl EncryptCtr32 for Key {
fn ctr32_encrypt_within(&self, in_out: Overlapping<'_>, ctr: &mut Counter) {
unsafe { ctr32_encrypt_blocks!(aes_hw_ctr32_encrypt_blocks, in_out, &self.inner, ctr) }
}
}