fixup first commit

Author: baloo

tss-esapi/src/abstraction/public.rs

@@ -3,6 +3,7 @@
 
 use crate::interface_types::ecc::EccCurve;
 use crate::structures::{Public, RsaExponent};
+use crate::utils::PublicKey as TpmPublicKey;
 use crate::{Error, WrapperErrorKind};
 
 use core::convert::TryFrom;
@@ -144,6 +145,60 @@ impl TryFrom<&Public> for SubjectPublicKeyInfoOwned {
     }
 }
 
+impl<C> TryFrom<&TpmPublicKey> for PublicKey<C>
+where
+    C: CurveArithmetic + AssociatedTpmCurve,
+    FieldBytesSize<C>: ModulusSize,
+    AffinePoint<C>: FromEncodedPoint<C> + ToEncodedPoint<C>,
+{
+    type Error = Error;
+
+    fn try_from(value: &TpmPublicKey) -> Result<Self, Self::Error> {
+        match value {
+            TpmPublicKey::Ecc { x, y } => {
+                let x = x.as_slice();
+                let y = y.as_slice();
+
+                // TODO: When elliptic_curve bumps to 0.14, we can use the TryFrom implementation instead
+                // of checking lengths manually
+                if x.len() != FieldBytesSize::<C>::USIZE {
+                    return Err(Error::local_error(WrapperErrorKind::InvalidParam));
+                }
+                if y.len() != FieldBytesSize::<C>::USIZE {
+                    return Err(Error::local_error(WrapperErrorKind::InvalidParam));
+                }
+
+                let encoded_point =
+                    EncodedPoint::<C>::from_affine_coordinates(x.into(), y.into(), false);
+                let public_key = PublicKey::<C>::try_from(&encoded_point)
+                    .map_err(|_| Error::local_error(WrapperErrorKind::InvalidParam))?;
+
+                Ok(public_key)
+            }
+            _ => Err(Error::local_error(WrapperErrorKind::UnsupportedParam)),
+        }
+    }
+}
+
+impl TryFrom<&TpmPublicKey> for RsaPublicKey {
+    type Error = Error;
+
+    fn try_from(value: &TpmPublicKey) -> Result<Self, Self::Error> {
+        match value {
+            TpmPublicKey::Rsa(modulus) => {
+                let exponent = BigUint::from(65537u32);
+                let modulus = BigUint::from_bytes_be(modulus.as_slice());
+
+                let public_key = RsaPublicKey::new(modulus, exponent)
+                    .map_err(|_| Error::local_error(WrapperErrorKind::InvalidParam))?;
+
+                Ok(public_key)
+            }
+            _ => Err(Error::local_error(WrapperErrorKind::UnsupportedParam)),
+        }
+    }
+}
+
 /// Provides the value of the curve used in this crate for the specific curve.
 pub trait AssociatedTpmCurve {
     /// Value of the curve when interacting with the TPM.