elliptic-curve: remove ToString and FromStr impls

elliptic-curve/src/jwk.rs

@@ -8,16 +8,12 @@ use crate::{
     secret_key::SecretKey,
     Curve, Error, FieldBytes, FieldBytesSize, Result,
 };
-use alloc::{
-    borrow::ToOwned,
-    format,
-    string::{String, ToString},
-};
+use alloc::{borrow::ToOwned, format, string::String};
 use base64ct::{Base64UrlUnpadded as Base64Url, Encoding};
 use core::{
     fmt::{self, Debug},
     marker::PhantomData,
-    str::{self, FromStr},
+    str,
 };
 use serdect::serde::{de, ser, Deserialize, Serialize};
 use zeroize::{Zeroize, ZeroizeOnDrop};
@@ -158,20 +154,15 @@ impl JwkEcKey {
     {
         self.try_into()
     }
-}
 
-impl FromStr for JwkEcKey {
-    type Err = Error;
-
-    fn from_str(s: &str) -> Result<Self> {
+    /// Decode from JSON string.
+    pub fn from_json(s: &str) -> Result<Self> {
         serde_json::from_str(s).map_err(|_| Error)
     }
-}
 
-#[allow(clippy::to_string_trait_impl)]
-impl ToString for JwkEcKey {
-    fn to_string(&self) -> String {
-        serde_json::to_string(self).expect("JWK encoding error")
+    /// Encode to JSON string.
+    pub fn to_json(&self) -> Result<String> {
+        serde_json::to_string(self).map_err(|_| Error)
     }
 }
 
@@ -613,7 +604,7 @@ mod tests {
 
     #[test]
     fn parse_private_key() {
-        let jwk = JwkEcKey::from_str(JWK_PRIVATE_KEY).unwrap();
+        let jwk = JwkEcKey::from_json(JWK_PRIVATE_KEY).unwrap();
         assert_eq!(jwk.crv, "P-256");
         assert_eq!(jwk.x, "gI0GAILBdu7T53akrFmMyGcsF3n5dO7MmwNBHKW5SV0");
         assert_eq!(jwk.y, "SLW_xSffzlPWrHEVI30DHM_4egVwt3NQqeUD7nMFpps");
@@ -625,7 +616,7 @@ mod tests {
 
     #[test]
     fn parse_public_key() {
-        let jwk = JwkEcKey::from_str(JWK_PUBLIC_KEY).unwrap();
+        let jwk = JwkEcKey::from_json(JWK_PUBLIC_KEY).unwrap();
         assert_eq!(jwk.crv, "P-256");
         assert_eq!(jwk.x, "gI0GAILBdu7T53akrFmMyGcsF3n5dO7MmwNBHKW5SV0");
         assert_eq!(jwk.y, "SLW_xSffzlPWrHEVI30DHM_4egVwt3NQqeUD7nMFpps");
@@ -634,27 +625,33 @@ mod tests {
 
     #[test]
     fn parse_unsupported() {
-        assert_eq!(JwkEcKey::from_str(UNSUPPORTED_JWK), Err(Error));
+        assert_eq!(JwkEcKey::from_json(UNSUPPORTED_JWK), Err(Error));
     }
 
     #[test]
     fn serialize_private_key() {
-        let actual = JwkEcKey::from_str(JWK_PRIVATE_KEY).unwrap().to_string();
+        let actual = JwkEcKey::from_json(JWK_PRIVATE_KEY)
+            .unwrap()
+            .to_json()
+            .unwrap();
         let expected: String = JWK_PRIVATE_KEY.split_whitespace().collect();
         assert_eq!(actual, expected);
     }
 
     #[test]
     fn serialize_public_key() {
-        let actual = JwkEcKey::from_str(JWK_PUBLIC_KEY).unwrap().to_string();
+        let actual = JwkEcKey::from_json(JWK_PUBLIC_KEY)
+            .unwrap()
+            .to_json()
+            .unwrap();
         let expected: String = JWK_PUBLIC_KEY.split_whitespace().collect();
         assert_eq!(actual, expected);
     }
 
     #[cfg(feature = "dev")]
     #[test]
     fn jwk_into_encoded_point() {
-        let jwk = JwkEcKey::from_str(JWK_PUBLIC_KEY).unwrap();
+        let jwk = JwkEcKey::from_json(JWK_PUBLIC_KEY).unwrap();
         let point = jwk.to_encoded_point::<MockCurve>().unwrap();
         let (x, y) = match point.coordinates() {
             Coordinates::Uncompressed { x, y } => (x, y),
@@ -668,7 +665,7 @@ mod tests {
     #[cfg(feature = "dev")]
     #[test]
     fn encoded_point_into_jwk() {
-        let jwk = JwkEcKey::from_str(JWK_PUBLIC_KEY).unwrap();
+        let jwk = JwkEcKey::from_json(JWK_PUBLIC_KEY).unwrap();
         let point = jwk.to_encoded_point::<MockCurve>().unwrap();
         let jwk2 = JwkEcKey::from_encoded_point::<MockCurve>(&point).unwrap();
         assert_eq!(jwk, jwk2);

elliptic-curve/src/public_key.rs

@@ -12,9 +12,6 @@ use crate::{JwkEcKey, JwkParameters};
 #[cfg(feature = "pkcs8")]
 use pkcs8::spki::{AlgorithmIdentifier, AssociatedAlgorithmIdentifier, ObjectIdentifier};
 
-#[cfg(feature = "pem")]
-use core::str::FromStr;
-
 #[cfg(feature = "sec1")]
 use {
     crate::{
@@ -33,7 +30,7 @@ use pkcs8::EncodePublicKey;
 use alloc::boxed::Box;
 
 #[cfg(any(feature = "jwk", feature = "pem"))]
-use alloc::string::{String, ToString};
+use alloc::string::String;
 
 #[cfg(feature = "serde")]
 use serdect::serde::{de, ser, Deserialize, Serialize};
@@ -71,9 +68,6 @@ use {
 /// [`elliptic_curve::pkcs8::DecodePublicKey`][`pkcs8::DecodePublicKey`]
 /// trait to parse it.
 ///
-/// When the `pem` feature of this crate (or a specific RustCrypto elliptic
-/// curve crate) is enabled, a [`FromStr`] impl is also available.
-///
 /// # `serde` support
 ///
 /// When the optional `serde` feature of this create is enabled, [`Serialize`]
@@ -181,7 +175,7 @@ where
         AffinePoint<C>: FromEncodedPoint<C> + ToEncodedPoint<C>,
         FieldBytesSize<C>: ModulusSize,
     {
-        jwk.parse::<JwkEcKey>().and_then(|jwk| Self::from_jwk(&jwk))
+        JwkEcKey::from_json(jwk).and_then(|jwk| Self::from_jwk(&jwk))
     }
 
     /// Serialize this public key as [`JwkEcKey`] JSON Web Key (JWK).
@@ -203,7 +197,7 @@ where
         AffinePoint<C>: FromEncodedPoint<C> + ToEncodedPoint<C>,
         FieldBytesSize<C>: ModulusSize,
     {
-        self.to_jwk().to_string()
+        self.to_jwk().to_json().expect("JWK encoding error")
     }
 }
 
@@ -488,34 +482,6 @@ where
     }
 }
 
-#[cfg(feature = "pem")]
-impl<C> FromStr for PublicKey<C>
-where
-    C: AssociatedOid + CurveArithmetic,
-    AffinePoint<C>: FromEncodedPoint<C> + ToEncodedPoint<C>,
-    FieldBytesSize<C>: ModulusSize,
-{
-    type Err = Error;
-
-    fn from_str(s: &str) -> Result<Self> {
-        Self::from_public_key_pem(s).map_err(|_| Error)
-    }
-}
-
-#[cfg(feature = "pem")]
-#[allow(clippy::to_string_trait_impl)]
-impl<C> ToString for PublicKey<C>
-where
-    C: AssociatedOid + CurveArithmetic,
-    AffinePoint<C>: FromEncodedPoint<C> + ToEncodedPoint<C>,
-    FieldBytesSize<C>: ModulusSize,
-{
-    fn to_string(&self) -> String {
-        self.to_public_key_pem(Default::default())
-            .expect("PEM encoding error")
-    }
-}
-
 #[cfg(feature = "serde")]
 impl<C> Serialize for PublicKey<C>
 where

elliptic-curve/src/secret_key.rs

@@ -45,11 +45,8 @@ use {
 #[cfg(all(feature = "arithmetic", any(feature = "jwk", feature = "pem")))]
 use alloc::string::String;
 
-#[cfg(all(feature = "arithmetic", feature = "jwk"))]
-use alloc::string::ToString;
-
 #[cfg(all(doc, feature = "pkcs8"))]
-use {crate::pkcs8::DecodePrivateKey, core::str::FromStr};
+use crate::pkcs8::DecodePrivateKey;
 
 /// Elliptic curve secret keys.
 ///
@@ -71,9 +68,6 @@ use {crate::pkcs8::DecodePrivateKey, core::str::FromStr};
 /// To decode an elliptic curve private key from PKCS#8, enable the `pkcs8`
 /// feature of this crate (or the `pkcs8` feature of a specific RustCrypto
 /// elliptic curve crate) and use the [`DecodePrivateKey`]  trait to parse it.
-///
-/// When the `pem` feature of this crate (or a specific RustCrypto elliptic
-/// curve crate) is enabled, a [`FromStr`] impl is also available.
 #[derive(Clone)]
 pub struct SecretKey<C: Curve> {
     /// Scalar value
@@ -273,7 +267,7 @@ where
         C: JwkParameters + ValidatePublicKey,
         FieldBytesSize<C>: ModulusSize,
     {
-        jwk.parse::<JwkEcKey>().and_then(|jwk| Self::from_jwk(&jwk))
+        JwkEcKey::from_json(jwk).and_then(|jwk| Self::from_jwk(&jwk))
     }
 
     /// Serialize this secret key as [`JwkEcKey`] JSON Web Key (JWK).
@@ -295,7 +289,7 @@ where
         AffinePoint<C>: FromEncodedPoint<C> + ToEncodedPoint<C>,
         FieldBytesSize<C>: ModulusSize,
     {
-        Zeroizing::new(self.to_jwk().to_string())
+        Zeroizing::new(self.to_jwk().to_json().expect("JWK encoding error"))
     }
 }
 

elliptic-curve/src/secret_key/pkcs8.rs

@@ -19,14 +19,6 @@ use {
     pkcs8::{der, EncodePrivateKey},
 };
 
-// Imports for actual PEM support
-#[cfg(feature = "pem")]
-use {
-    crate::{error::Error, Result},
-    core::str::FromStr,
-    pkcs8::DecodePrivateKey,
-};
-
 impl<C> AssociatedAlgorithmIdentifier for SecretKey<C>
 where
     C: AssociatedOid + Curve,
@@ -75,16 +67,3 @@ where
         Ok(der::SecretDocument::encode_msg(&pkcs8_key)?)
     }
 }
-
-#[cfg(feature = "pem")]
-impl<C> FromStr for SecretKey<C>
-where
-    C: Curve + AssociatedOid + ValidatePublicKey,
-    FieldBytesSize<C>: ModulusSize,
-{
-    type Err = Error;
-
-    fn from_str(s: &str) -> Result<Self> {
-        Self::from_pkcs8_pem(s).map_err(|_| Error)
-    }
-}

elliptic-curve/tests/pkcs8.rs

@@ -49,7 +49,7 @@ fn decode_pkcs8_public_key_from_der() {
 #[test]
 #[cfg(feature = "pem")]
 fn decode_pkcs8_public_key_from_pem() {
-    let public_key = PKCS8_PUBLIC_KEY_PEM.parse::<PublicKey>().unwrap();
+    let public_key = PublicKey::from_public_key_pem(PKCS8_PUBLIC_KEY_PEM).unwrap();
 
     // Ensure key parses equivalently to DER
     let der_key = PublicKey::from_public_key_der(&PKCS8_PUBLIC_KEY_DER[..]).unwrap();