diff options
Diffstat (limited to 'openpgp/src/crypto/backend/rust/asymmetric.rs')
| -rw-r--r-- | openpgp/src/crypto/backend/rust/asymmetric.rs | 86 |
1 files changed, 19 insertions, 67 deletions
diff --git a/openpgp/src/crypto/backend/rust/asymmetric.rs b/openpgp/src/crypto/backend/rust/asymmetric.rs index 5bee9ecd..7df6ecf6 100644 --- a/openpgp/src/crypto/backend/rust/asymmetric.rs +++ b/openpgp/src/crypto/backend/rust/asymmetric.rs @@ -24,8 +24,6 @@ use crate::types::{Curve, HashAlgorithm, PublicKeyAlgorithm}; use super::GenericArrayExt; -const CURVE25519_SIZE: usize = 32; - impl TryFrom<&Protected> for Box<ed25519_dalek::SigningKey> { type Error = anyhow::Error; @@ -557,62 +555,17 @@ impl<R> Key4<SecretParts, R> /// EdDSA or ECDSA key is generated. Giving `for_signing == true` and /// `curve == Cv25519` will produce an error. Likewise /// `for_signing == false` and `curve == Ed25519` will produce an error. - pub fn generate_ecc(for_signing: bool, curve: Curve) -> Result<Self> { - let hash = crate::crypto::ecdh::default_ecdh_kdf_hash(&curve); - let sym = crate::crypto::ecdh::default_ecdh_kek_cipher(&curve); - - let (algo, public, private) = match (&curve, for_signing) { - (Curve::Ed25519, true) => { - use ed25519_dalek::SigningKey; - - use rand::rngs::OsRng as OsRng; - - let key = SigningKey::generate(&mut OsRng); - - let secret: Protected = key.to_bytes().as_ref().into(); - - // Mark MPI as compressed point with 0x40 prefix. See - // https://tools.ietf.org/html/draft-ietf-openpgp-rfc4880bis-07#section-13.2. - let mut compressed_public = [0u8; 1 + CURVE25519_SIZE]; - compressed_public[0] = 0x40; - compressed_public[1..].copy_from_slice(key.verifying_key().as_bytes()); - - ( - PublicKeyAlgorithm::EdDSA, - mpi::PublicKey::EdDSA { curve, q: mpi::MPI::new(&compressed_public) }, - mpi::SecretKeyMaterial::EdDSA { scalar: secret.into() }, - ) - } - - (Curve::Cv25519, false) => { - let (mut private, public) = - super::Backend::x25519_generate_key()?; - - // x25519-dalek since v 2.0.0-rc.3 does not return clamped - // integers from Static Secrets but clamps them on usage. - // See: https://github.com/dalek-cryptography/x25519-dalek/blob/main/CHANGELOG.md#200-rc3 - // - // Clamp the scalar. X25519 does the clamping implicitly, but - // OpenPGP's ECDH over Curve25519 requires the secret to be - // clamped. - private[0] &= 0b1111_1000; - private[31] &= !0b1000_0000; - private[31] |= 0b0100_0000; - - private.reverse(); - - let public_mpis = mpi::PublicKey::ECDH { - curve: Curve::Cv25519, - q: MPI::new_compressed_point(&public), - hash, - sym, - }; - let private_mpis = mpi::SecretKeyMaterial::ECDH { - scalar: private.into(), - }; + pub(crate) fn generate_ecc_backend(for_signing: bool, curve: Curve) + -> Result<(PublicKeyAlgorithm, + mpi::PublicKey, + mpi::SecretKeyMaterial)> + { + match (&curve, for_signing) { + (Curve::Ed25519, true) => + unreachable!("handled in Key4::generate_ecc"), - (PublicKeyAlgorithm::ECDH, public_mpis, private_mpis) - } + (Curve::Cv25519, false) => + unreachable!("handled in Key4::generate_ecc"), (Curve::NistP256, true) => { use p256::{EncodedPoint, SecretKey}; @@ -629,7 +582,7 @@ impl<R> Key4<SecretParts, R> scalar: Vec::from(secret.to_bytes().as_slice()).into(), }; - (PublicKeyAlgorithm::ECDSA, public_mpis, private_mpis) + Ok((PublicKeyAlgorithm::ECDSA, public_mpis, private_mpis)) }, (Curve::NistP256, false) => { @@ -640,23 +593,22 @@ impl<R> Key4<SecretParts, R> let public = EncodedPoint::from(secret.public_key()); let public_mpis = mpi::PublicKey::ECDH { - curve, q: MPI::new(public.as_bytes()), - hash, - sym, + hash: + crate::crypto::ecdh::default_ecdh_kdf_hash(&curve), + sym: + crate::crypto::ecdh::default_ecdh_kek_cipher(&curve), + curve, }; let private_mpis = mpi::SecretKeyMaterial::ECDH { scalar: Vec::from(secret.to_bytes().as_slice()).into(), }; - (PublicKeyAlgorithm::ECDH, public_mpis, private_mpis) + Ok((PublicKeyAlgorithm::ECDH, public_mpis, private_mpis)) }, - _ => { - return Err(Error::UnsupportedEllipticCurve(curve).into()); - } - }; - Self::with_secret(crate::now(), algo, public, private.into()) + _ => Err(Error::UnsupportedEllipticCurve(curve).into()), + } } } |