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//! Implementation of Sequoia crypto API using the OpenSSL cryptographic library.
use crate::types::*;
pub mod aead;
pub mod asymmetric;
pub mod ecdh;
pub mod hash;
pub mod symmetric;
pub struct Backend(());
impl super::interface::Backend for Backend {
fn backend() -> String {
"OpenSSL".to_string()
}
fn random(buf: &mut [u8]) -> crate::Result<()> {
openssl::rand::rand_bytes(buf)?;
Ok(())
}
}
impl AEADAlgorithm {
/// Returns the best AEAD mode supported by the backend.
///
/// This SHOULD return OCB, which is the mandatory-to-implement
/// algorithm and the most performing one, but fall back to any
/// supported algorithm.
pub(crate) const fn const_default() -> AEADAlgorithm {
if cfg!(not(osslconf = "OPENSSL_NO_OCB")) {
AEADAlgorithm::OCB
} else {
AEADAlgorithm::GCM
}
}
pub(crate) fn is_supported_by_backend(&self) -> bool {
match self {
AEADAlgorithm::EAX => false,
AEADAlgorithm::OCB => cfg!(not(osslconf = "OPENSSL_NO_OCB")),
AEADAlgorithm::GCM => true,
AEADAlgorithm::Private(_) |
AEADAlgorithm::Unknown(_) => false,
}
}
#[cfg(test)]
pub(crate) fn supports_symmetric_algo(&self, algo: &SymmetricAlgorithm) -> bool {
match &self {
AEADAlgorithm::EAX => false,
AEADAlgorithm::OCB =>
match algo {
// OpenSSL supports OCB only with AES
// see: https://wiki.openssl.org/index.php/OCB
SymmetricAlgorithm::AES128 |
SymmetricAlgorithm::AES192 |
SymmetricAlgorithm::AES256 => true,
_ => false,
},
AEADAlgorithm::GCM =>
match algo {
// OpenSSL supports GCM only with AES
// see: https://wiki.openssl.org/index.php/GCM
SymmetricAlgorithm::AES128 |
SymmetricAlgorithm::AES192 |
SymmetricAlgorithm::AES256 => true,
_ => false,
},
AEADAlgorithm::Private(_) |
AEADAlgorithm::Unknown(_) => false,
}
}
}