denoland-deno/ext/crypto/import_key.rs

// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.

use base64::Engine;
use deno_core::error::AnyError;
use deno_core::op2;
use deno_core::JsBuffer;
use deno_core::ToJsBuffer;
use elliptic_curve::pkcs8::PrivateKeyInfo;
use p256::pkcs8::EncodePrivateKey;
use ring::signature::EcdsaKeyPair;
use rsa::pkcs1::UintRef;
use rsa::pkcs8::der::Encode;
use serde::Deserialize;
use serde::Serialize;
use spki::der::Decode;

use crate::key::CryptoNamedCurve;
use crate::shared::*;

#[derive(Deserialize)]
#[serde(rename_all = "camelCase")]
pub enum KeyData {
  Spki(JsBuffer),
  Pkcs8(JsBuffer),
  Raw(JsBuffer),
  JwkSecret {
    k: String,
  },
  JwkPublicRsa {
    n: String,
    e: String,
  },
  JwkPrivateRsa {
    n: String,
    e: String,
    d: String,
    p: String,
    q: String,
    dp: String,
    dq: String,
    qi: String,
  },
  JwkPublicEc {
    x: String,
    y: String,
  },
  JwkPrivateEc {
    x: String,
    y: String,
    d: String,
  },
}

#[derive(Deserialize)]
#[serde(rename_all = "camelCase", tag = "algorithm")]
pub enum ImportKeyOptions {
  #[serde(rename = "RSASSA-PKCS1-v1_5")]
  RsassaPkcs1v15 {},
  #[serde(rename = "RSA-PSS")]
  RsaPss {},
  #[serde(rename = "RSA-OAEP")]
  RsaOaep {},
  #[serde(rename = "ECDSA", rename_all = "camelCase")]
  Ecdsa { named_curve: EcNamedCurve },
  #[serde(rename = "ECDH", rename_all = "camelCase")]
  Ecdh { named_curve: EcNamedCurve },
  #[serde(rename = "AES", rename_all = "camelCase")]
  Aes {},
  #[serde(rename = "HMAC", rename_all = "camelCase")]
  Hmac {},
}

#[derive(Serialize)]
#[serde(untagged)]
pub enum ImportKeyResult {
  #[serde(rename_all = "camelCase")]
  Rsa {
    raw_data: RustRawKeyData,
    modulus_length: usize,
    public_exponent: ToJsBuffer,
  },
  #[serde(rename_all = "camelCase")]
  Ec { raw_data: RustRawKeyData },
  #[serde(rename_all = "camelCase")]
  #[allow(dead_code)]
  Aes { raw_data: RustRawKeyData },
  #[serde(rename_all = "camelCase")]
  Hmac { raw_data: RustRawKeyData },
}

#[op2]
#[serde]
pub fn op_crypto_import_key(
  #[serde] opts: ImportKeyOptions,
  #[serde] key_data: KeyData,
) -> Result<ImportKeyResult, AnyError> {
  match opts {
    ImportKeyOptions::RsassaPkcs1v15 {} => import_key_rsassa(key_data),
    ImportKeyOptions::RsaPss {} => import_key_rsapss(key_data),
    ImportKeyOptions::RsaOaep {} => import_key_rsaoaep(key_data),
    ImportKeyOptions::Ecdsa { named_curve }
    | ImportKeyOptions::Ecdh { named_curve } => {
      import_key_ec(key_data, named_curve)
    }
    ImportKeyOptions::Aes {} => import_key_aes(key_data),
    ImportKeyOptions::Hmac {} => import_key_hmac(key_data),
  }
}

const BASE64_URL_SAFE_FORGIVING:
  base64::engine::general_purpose::GeneralPurpose =
  base64::engine::general_purpose::GeneralPurpose::new(
    &base64::alphabet::URL_SAFE,
    base64::engine::general_purpose::GeneralPurposeConfig::new()
      .with_decode_allow_trailing_bits(true)
      .with_decode_padding_mode(base64::engine::DecodePaddingMode::Indifferent),
  );

macro_rules! jwt_b64_int_or_err {
  ($name:ident, $b64:expr, $err:expr) => {
    let bytes = BASE64_URL_SAFE_FORGIVING
      .decode($b64)
      .map_err(|_| data_error($err))?;
    let $name = UintRef::new(&bytes).map_err(|_| data_error($err))?;
  };
}

fn import_key_rsa_jwk(
  key_data: KeyData,
) -> Result<ImportKeyResult, deno_core::anyhow::Error> {
  match key_data {
    KeyData::JwkPublicRsa { n, e } => {
      jwt_b64_int_or_err!(modulus, &n, "invalid modulus");
      jwt_b64_int_or_err!(public_exponent, &e, "invalid public exponent");

      let public_key = rsa::pkcs1::RsaPublicKey {
        modulus,
        public_exponent,
      };

      let mut data = Vec::new();
      public_key
        .encode_to_vec(&mut data)
        .map_err(|_| data_error("invalid rsa public key"))?;

      let public_exponent =
        public_key.public_exponent.as_bytes().to_vec().into();
      let modulus_length = public_key.modulus.as_bytes().len() * 8;

      Ok(ImportKeyResult::Rsa {
        raw_data: RustRawKeyData::Public(data.into()),
        modulus_length,
        public_exponent,
      })
    }
    KeyData::JwkPrivateRsa {
      n,
      e,
      d,
      p,
      q,
      dp,
      dq,
      qi,
    } => {
      jwt_b64_int_or_err!(modulus, &n, "invalid modulus");
      jwt_b64_int_or_err!(public_exponent, &e, "invalid public exponent");
      jwt_b64_int_or_err!(private_exponent, &d, "invalid private exponent");
      jwt_b64_int_or_err!(prime1, &p, "invalid first prime factor");
      jwt_b64_int_or_err!(prime2, &q, "invalid second prime factor");
      jwt_b64_int_or_err!(exponent1, &dp, "invalid first CRT exponent");
      jwt_b64_int_or_err!(exponent2, &dq, "invalid second CRT exponent");
      jwt_b64_int_or_err!(coefficient, &qi, "invalid CRT coefficient");

      let private_key = rsa::pkcs1::RsaPrivateKey {
        modulus,
        public_exponent,
        private_exponent,
        prime1,
        prime2,
        exponent1,
        exponent2,
        coefficient,
        other_prime_infos: None,
      };

      let mut data = Vec::new();
      private_key
        .encode_to_vec(&mut data)
        .map_err(|_| data_error("invalid rsa private key"))?;

      let public_exponent =
        private_key.public_exponent.as_bytes().to_vec().into();
      let modulus_length = private_key.modulus.as_bytes().len() * 8;

      Ok(ImportKeyResult::Rsa {
        raw_data: RustRawKeyData::Private(data.into()),
        modulus_length,
        public_exponent,
      })
    }
    _ => unreachable!(),
  }
}

fn import_key_rsassa(
  key_data: KeyData,
) -> Result<ImportKeyResult, deno_core::anyhow::Error> {
  match key_data {
    KeyData::Spki(data) => {
      // 2-3.
      let pk_info = spki::SubjectPublicKeyInfoRef::try_from(&*data)
        .map_err(|e| data_error(e.to_string()))?;

      // 4-5.
      let alg = pk_info.algorithm.oid;

      // 6-7. (skipped, only support rsaEncryption for interoperability)
      if alg != RSA_ENCRYPTION_OID {
        return Err(data_error("unsupported algorithm"));
      }

      // 8-9.
      let public_key = rsa::pkcs1::RsaPublicKey::from_der(
        pk_info.subject_public_key.raw_bytes(),
      )
      .map_err(|e| data_error(e.to_string()))?;

      let bytes_consumed = public_key
        .encoded_len()
        .map_err(|e| data_error(e.to_string()))?;

      if bytes_consumed
        != rsa::pkcs1::der::Length::new(
          pk_info.subject_public_key.raw_bytes().len() as u16,
        )
      {
        return Err(data_error("public key is invalid (too long)"));
      }

      let data = pk_info.subject_public_key.raw_bytes().to_vec().into();
      let public_exponent =
        public_key.public_exponent.as_bytes().to_vec().into();
      let modulus_length = public_key.modulus.as_bytes().len() * 8;

      Ok(ImportKeyResult::Rsa {
        raw_data: RustRawKeyData::Public(data),
        modulus_length,
        public_exponent,
      })
    }
    KeyData::Pkcs8(data) => {
      // 2-3.
      let pk_info = PrivateKeyInfo::from_der(&data)
        .map_err(|e| data_error(e.to_string()))?;

      // 4-5.
      let alg = pk_info.algorithm.oid;

      // 6-7. (skipped, only support rsaEncryption for interoperability)
      if alg != RSA_ENCRYPTION_OID {
        return Err(data_error("unsupported algorithm"));
      }

      // 8-9.
      let private_key =
        rsa::pkcs1::RsaPrivateKey::from_der(pk_info.private_key)
          .map_err(|e| data_error(e.to_string()))?;

      let bytes_consumed = private_key
        .encoded_len()
        .map_err(|e| data_error(e.to_string()))?;

      if bytes_consumed
        != rsa::pkcs1::der::Length::new(pk_info.private_key.len() as u16)
      {
        return Err(data_error("private key is invalid (too long)"));
      }

      let data = pk_info.private_key.to_vec().into();
      let public_exponent =
        private_key.public_exponent.as_bytes().to_vec().into();
      let modulus_length = private_key.modulus.as_bytes().len() * 8;

      Ok(ImportKeyResult::Rsa {
        raw_data: RustRawKeyData::Private(data),
        modulus_length,
        public_exponent,
      })
    }
    KeyData::JwkPublicRsa { .. } | KeyData::JwkPrivateRsa { .. } => {
      import_key_rsa_jwk(key_data)
    }
    _ => Err(unsupported_format()),
  }
}

fn import_key_rsapss(
  key_data: KeyData,
) -> Result<ImportKeyResult, deno_core::anyhow::Error> {
  match key_data {
    KeyData::Spki(data) => {
      // 2-3.
      let pk_info = spki::SubjectPublicKeyInfoRef::try_from(&*data)
        .map_err(|e| data_error(e.to_string()))?;

      // 4-5.
      let alg = pk_info.algorithm.oid;

      // 6-7. (skipped, only support rsaEncryption for interoperability)
      if alg != RSA_ENCRYPTION_OID {
        return Err(data_error("unsupported algorithm"));
      }

      // 8-9.
      let public_key = rsa::pkcs1::RsaPublicKey::from_der(
        pk_info.subject_public_key.raw_bytes(),
      )
      .map_err(|e| data_error(e.to_string()))?;

      let bytes_consumed = public_key
        .encoded_len()
        .map_err(|e| data_error(e.to_string()))?;

      if bytes_consumed
        != rsa::pkcs1::der::Length::new(
          pk_info.subject_public_key.raw_bytes().len() as u16,
        )
      {
        return Err(data_error("public key is invalid (too long)"));
      }

      let data = pk_info.subject_public_key.raw_bytes().to_vec().into();
      let public_exponent =
        public_key.public_exponent.as_bytes().to_vec().into();
      let modulus_length = public_key.modulus.as_bytes().len() * 8;

      Ok(ImportKeyResult::Rsa {
        raw_data: RustRawKeyData::Public(data),
        modulus_length,
        public_exponent,
      })
    }
    KeyData::Pkcs8(data) => {
      // 2-3.
      let pk_info = PrivateKeyInfo::from_der(&data)
        .map_err(|e| data_error(e.to_string()))?;

      // 4-5.
      let alg = pk_info.algorithm.oid;

      // 6-7. (skipped, only support rsaEncryption for interoperability)
      if alg != RSA_ENCRYPTION_OID {
        return Err(data_error("unsupported algorithm"));
      }

      // 8-9.
      let private_key =
        rsa::pkcs1::RsaPrivateKey::from_der(pk_info.private_key)
          .map_err(|e| data_error(e.to_string()))?;

      let bytes_consumed = private_key
        .encoded_len()
        .map_err(|e| data_error(e.to_string()))?;

      if bytes_consumed
        != rsa::pkcs1::der::Length::new(pk_info.private_key.len() as u16)
      {
        return Err(data_error("private key is invalid (too long)"));
      }

      let data = pk_info.private_key.to_vec().into();
      let public_exponent =
        private_key.public_exponent.as_bytes().to_vec().into();
      let modulus_length = private_key.modulus.as_bytes().len() * 8;

      Ok(ImportKeyResult::Rsa {
        raw_data: RustRawKeyData::Private(data),
        modulus_length,
        public_exponent,
      })
    }
    KeyData::JwkPublicRsa { .. } | KeyData::JwkPrivateRsa { .. } => {
      import_key_rsa_jwk(key_data)
    }
    _ => Err(unsupported_format()),
  }
}

fn import_key_rsaoaep(
  key_data: KeyData,
) -> Result<ImportKeyResult, deno_core::anyhow::Error> {
  match key_data {
    KeyData::Spki(data) => {
      // 2-3.
      let pk_info = spki::SubjectPublicKeyInfoRef::try_from(&*data)
        .map_err(|e| data_error(e.to_string()))?;

      // 4-5.
      let alg = pk_info.algorithm.oid;

      // 6-7. (skipped, only support rsaEncryption for interoperability)
      if alg != RSA_ENCRYPTION_OID {
        return Err(data_error("unsupported algorithm"));
      }

      // 8-9.
      let public_key = rsa::pkcs1::RsaPublicKey::from_der(
        pk_info.subject_public_key.raw_bytes(),
      )
      .map_err(|e| data_error(e.to_string()))?;

      let bytes_consumed = public_key
        .encoded_len()
        .map_err(|e| data_error(e.to_string()))?;

      if bytes_consumed
        != rsa::pkcs1::der::Length::new(
          pk_info.subject_public_key.raw_bytes().len() as u16,
        )
      {
        return Err(data_error("public key is invalid (too long)"));
      }

      let data = pk_info.subject_public_key.raw_bytes().to_vec().into();
      let public_exponent =
        public_key.public_exponent.as_bytes().to_vec().into();
      let modulus_length = public_key.modulus.as_bytes().len() * 8;

      Ok(ImportKeyResult::Rsa {
        raw_data: RustRawKeyData::Public(data),
        modulus_length,
        public_exponent,
      })
    }
    KeyData::Pkcs8(data) => {
      // 2-3.
      let pk_info = PrivateKeyInfo::from_der(&data)
        .map_err(|e| data_error(e.to_string()))?;

      // 4-5.
      let alg = pk_info.algorithm.oid;

      // 6-7. (skipped, only support rsaEncryption for interoperability)
      if alg != RSA_ENCRYPTION_OID {
        return Err(data_error("unsupported algorithm"));
      }

      // 8-9.
      let private_key =
        rsa::pkcs1::RsaPrivateKey::from_der(pk_info.private_key)
          .map_err(|e| data_error(e.to_string()))?;

      let bytes_consumed = private_key
        .encoded_len()
        .map_err(|e| data_error(e.to_string()))?;

      if bytes_consumed
        != rsa::pkcs1::der::Length::new(pk_info.private_key.len() as u16)
      {
        return Err(data_error("private key is invalid (too long)"));
      }

      let data = pk_info.private_key.to_vec().into();
      let public_exponent =
        private_key.public_exponent.as_bytes().to_vec().into();
      let modulus_length = private_key.modulus.as_bytes().len() * 8;

      Ok(ImportKeyResult::Rsa {
        raw_data: RustRawKeyData::Private(data),
        modulus_length,
        public_exponent,
      })
    }
    KeyData::JwkPublicRsa { .. } | KeyData::JwkPrivateRsa { .. } => {
      import_key_rsa_jwk(key_data)
    }
    _ => Err(unsupported_format()),
  }
}

fn decode_b64url_to_field_bytes<C: elliptic_curve::Curve>(
  b64: &str,
) -> Result<elliptic_curve::FieldBytes<C>, deno_core::anyhow::Error> {
  jwt_b64_int_or_err!(val, b64, "invalid b64 coordinate");

  let mut bytes = elliptic_curve::FieldBytes::<C>::default();
  let original_bytes = val.as_bytes();
  let mut new_bytes: Vec<u8> = vec![];
  if original_bytes.len() < bytes.len() {
    new_bytes = vec![0; bytes.len() - original_bytes.len()];
  }
  new_bytes.extend_from_slice(original_bytes);

  let val = new_bytes.as_slice();

  if val.len() != bytes.len() {
    return Err(data_error("invalid b64 coordinate"));
  }
  bytes.copy_from_slice(val);

  Ok(bytes)
}

fn import_key_ec_jwk_to_point(
  x: String,
  y: String,
  named_curve: EcNamedCurve,
) -> Result<Vec<u8>, deno_core::anyhow::Error> {
  let point_bytes = match named_curve {
    EcNamedCurve::P256 => {
      let x = decode_b64url_to_field_bytes::<p256::NistP256>(&x)?;
      let y = decode_b64url_to_field_bytes::<p256::NistP256>(&y)?;

      p256::EncodedPoint::from_affine_coordinates(&x, &y, false).to_bytes()
    }
    EcNamedCurve::P384 => {
      let x = decode_b64url_to_field_bytes::<p384::NistP384>(&x)?;
      let y = decode_b64url_to_field_bytes::<p384::NistP384>(&y)?;

      p384::EncodedPoint::from_affine_coordinates(&x, &y, false).to_bytes()
    }
    EcNamedCurve::P521 => {
      let x = decode_b64url_to_field_bytes::<p521::NistP521>(&x)?;
      let y = decode_b64url_to_field_bytes::<p521::NistP521>(&y)?;

      p521::EncodedPoint::from_affine_coordinates(&x, &y, false).to_bytes()
    }
  };

  Ok(point_bytes.to_vec())
}

fn import_key_ec_jwk(
  key_data: KeyData,
  named_curve: EcNamedCurve,
) -> Result<ImportKeyResult, deno_core::anyhow::Error> {
  match key_data {
    KeyData::JwkPublicEc { x, y } => {
      let point_bytes = import_key_ec_jwk_to_point(x, y, named_curve)?;

      Ok(ImportKeyResult::Ec {
        raw_data: RustRawKeyData::Public(point_bytes.into()),
      })
    }
    KeyData::JwkPrivateEc { d, x, y } => {
      jwt_b64_int_or_err!(private_d, &d, "invalid JWK private key");
      let point_bytes = import_key_ec_jwk_to_point(x, y, named_curve)?;
      let pkcs8_der = match named_curve {
        EcNamedCurve::P256 => {
          let d = decode_b64url_to_field_bytes::<p256::NistP256>(&d)?;
          let pk = p256::SecretKey::from_bytes(&d)?;

          pk.to_pkcs8_der()
            .map_err(|_| data_error("invalid JWK private key"))?
        }
        EcNamedCurve::P384 => {
          let d = decode_b64url_to_field_bytes::<p384::NistP384>(&d)?;
          let pk = p384::SecretKey::from_bytes(&d)?;

          pk.to_pkcs8_der()
            .map_err(|_| data_error("invalid JWK private key"))?
        }
        EcNamedCurve::P521 => {
          return Err(data_error("Unsupported named curve"))
        }
      };

      // Import using ring, to validate key
      let key_alg = match named_curve {
        EcNamedCurve::P256 => CryptoNamedCurve::P256.into(),
        EcNamedCurve::P384 => CryptoNamedCurve::P256.into(),
        EcNamedCurve::P521 => {
          return Err(data_error("Unsupported named curve"))
        }
      };

      let rng = ring::rand::SystemRandom::new();
      let _key_pair = EcdsaKeyPair::from_private_key_and_public_key(
        key_alg,
        private_d.as_bytes(),
        point_bytes.as_ref(),
        &rng,
      );

      Ok(ImportKeyResult::Ec {
        raw_data: RustRawKeyData::Private(pkcs8_der.as_bytes().to_vec().into()),
      })
    }
    _ => unreachable!(),
  }
}

pub struct ECParametersSpki {
  pub named_curve_alg: spki::der::asn1::ObjectIdentifier,
}

impl<'a> TryFrom<spki::der::asn1::AnyRef<'a>> for ECParametersSpki {
  type Error = spki::der::Error;

  fn try_from(
    any: spki::der::asn1::AnyRef<'a>,
  ) -> spki::der::Result<ECParametersSpki> {
    let x = any.try_into()?;

    Ok(Self { named_curve_alg: x })
  }
}

fn import_key_ec(
  key_data: KeyData,
  named_curve: EcNamedCurve,
) -> Result<ImportKeyResult, AnyError> {
  match key_data {
    KeyData::Raw(data) => {
      // The point is parsed and validated, ultimately the original data is
      // returned though.
      match named_curve {
        EcNamedCurve::P256 => {
          // 1-2.
          let point = p256::EncodedPoint::from_bytes(&data)
            .map_err(|_| data_error("invalid P-256 elliptic curve point"))?;
          // 3.
          if point.is_identity() {
            return Err(data_error("invalid P-256 elliptic curve point"));
          }
        }
        EcNamedCurve::P384 => {
          // 1-2.
          let point = p384::EncodedPoint::from_bytes(&data)
            .map_err(|_| data_error("invalid P-384 elliptic curve point"))?;
          // 3.
          if point.is_identity() {
            return Err(data_error("invalid P-384 elliptic curve point"));
          }
        }
        EcNamedCurve::P521 => {
          // 1-2.
          let point = p521::EncodedPoint::from_bytes(&data)
            .map_err(|_| data_error("invalid P-521 elliptic curve point"))?;
          // 3.
          if point.is_identity() {
            return Err(data_error("invalid P-521 elliptic curve point"));
          }
        }
      };
      Ok(ImportKeyResult::Ec {
        raw_data: RustRawKeyData::Public(data.to_vec().into()),
      })
    }
    KeyData::Pkcs8(data) => {
      // 2-7
      // Deserialize PKCS8 - validate structure, extracts named_curve
      let named_curve_alg = match named_curve {
        EcNamedCurve::P256 | EcNamedCurve::P384 => {
          let pk = PrivateKeyInfo::from_der(data.as_ref())
            .map_err(|_| data_error("expected valid PKCS#8 data"))?;
          pk.algorithm
            .parameters
            .ok_or_else(|| data_error("malformed parameters"))?
            .try_into()
            .unwrap()
        }
        EcNamedCurve::P521 => {
          return Err(data_error("Unsupported named curve"))
        }
      };

      // 8-9.
      let pk_named_curve = match named_curve_alg {
        // id-secp256r1
        ID_SECP256R1_OID => Some(EcNamedCurve::P256),
        // id-secp384r1
        ID_SECP384R1_OID => Some(EcNamedCurve::P384),
        // id-secp521r1
        ID_SECP521R1_OID => Some(EcNamedCurve::P521),
        _ => None,
      };

      // 10.
      if let Some(pk_named_curve) = pk_named_curve {
        let signing_alg = match pk_named_curve {
          EcNamedCurve::P256 => CryptoNamedCurve::P256.into(),
          EcNamedCurve::P384 => CryptoNamedCurve::P384.into(),
          EcNamedCurve::P521 => {
            return Err(data_error("Unsupported named curve"))
          }
        };

        let rng = ring::rand::SystemRandom::new();
        // deserialize pkcs8 using ring crate, to VALIDATE public key
        let _private_key = EcdsaKeyPair::from_pkcs8(signing_alg, &data, &rng)
          .map_err(|_| data_error("invalid key"))?;

        // 11.
        if named_curve != pk_named_curve {
          return Err(data_error("curve mismatch"));
        }
      } else {
        return Err(data_error("Unsupported named curve"));
      }

      Ok(ImportKeyResult::Ec {
        raw_data: RustRawKeyData::Private(data.to_vec().into()),
      })
    }
    KeyData::Spki(data) => {
      // 2-3.
      let pk_info = spki::SubjectPublicKeyInfoRef::try_from(&*data)
        .map_err(|e| data_error(e.to_string()))?;

      // 4.
      let alg = pk_info.algorithm.oid;
      // id-ecPublicKey
      if alg != elliptic_curve::ALGORITHM_OID {
        return Err(data_error("unsupported algorithm"));
      }

      // 5-7.
      let params = ECParametersSpki::try_from(
        pk_info
          .algorithm
          .parameters
          .ok_or_else(|| data_error("malformed parameters"))?,
      )
      .map_err(|_| data_error("malformed parameters"))?;

      // 8-9.
      let named_curve_alg = params.named_curve_alg;
      let pk_named_curve = match named_curve_alg {
        // id-secp256r1
        ID_SECP256R1_OID => Some(EcNamedCurve::P256),
        // id-secp384r1
        ID_SECP384R1_OID => Some(EcNamedCurve::P384),
        // id-secp521r1
        ID_SECP521R1_OID => Some(EcNamedCurve::P521),
        _ => None,
      };

      // 10.
      let encoded_key;

      if let Some(pk_named_curve) = pk_named_curve {
        let pk = pk_info.subject_public_key;

        encoded_key = pk.raw_bytes().to_vec();

        let bytes_consumed = match named_curve {
          EcNamedCurve::P256 => {
            let point =
              p256::EncodedPoint::from_bytes(&*encoded_key).map_err(|_| {
                data_error("invalid P-256 elliptic curve SPKI data")
              })?;
            if point.is_identity() {
              return Err(data_error("invalid P-256 elliptic curve point"));
            }

            point.as_bytes().len()
          }
          EcNamedCurve::P384 => {
            let point =
              p384::EncodedPoint::from_bytes(&*encoded_key).map_err(|_| {
                data_error("invalid P-384 elliptic curve SPKI data")
              })?;

            if point.is_identity() {
              return Err(data_error("invalid P-384 elliptic curve point"));
            }

            point.as_bytes().len()
          }
          EcNamedCurve::P521 => {
            let point =
              p521::EncodedPoint::from_bytes(&*encoded_key).map_err(|_| {
                data_error("invalid P-521 elliptic curve SPKI data")
              })?;

            if point.is_identity() {
              return Err(data_error("invalid P-521 elliptic curve point"));
            }

            point.as_bytes().len()
          }
        };

        if bytes_consumed != pk_info.subject_public_key.raw_bytes().len() {
          return Err(data_error("public key is invalid (too long)"));
        }

        // 11.
        if named_curve != pk_named_curve {
          return Err(data_error("curve mismatch"));
        }
      } else {
        return Err(data_error("Unsupported named curve"));
      }

      Ok(ImportKeyResult::Ec {
        raw_data: RustRawKeyData::Public(encoded_key.into()),
      })
    }
    KeyData::JwkPublicEc { .. } | KeyData::JwkPrivateEc { .. } => {
      import_key_ec_jwk(key_data, named_curve)
    }
    _ => Err(unsupported_format()),
  }
}

fn import_key_aes(key_data: KeyData) -> Result<ImportKeyResult, AnyError> {
  Ok(match key_data {
    KeyData::JwkSecret { k } => {
      let data = BASE64_URL_SAFE_FORGIVING
        .decode(k)
        .map_err(|_| data_error("invalid key data"))?;
      ImportKeyResult::Hmac {
        raw_data: RustRawKeyData::Secret(data.into()),
      }
    }
    _ => return Err(unsupported_format()),
  })
}

fn import_key_hmac(key_data: KeyData) -> Result<ImportKeyResult, AnyError> {
  Ok(match key_data {
    KeyData::JwkSecret { k } => {
      let data = BASE64_URL_SAFE_FORGIVING
        .decode(k)
        .map_err(|_| data_error("invalid key data"))?;
      ImportKeyResult::Hmac {
        raw_data: RustRawKeyData::Secret(data.into()),
      }
    }
    _ => return Err(unsupported_format()),
  })
}