1 files changed, 194 insertions, 0 deletions
diff --git a/vendor/spki/src/algorithm.rs b/vendor/spki/src/algorithm.rs
new file mode 100644
index 0000000..5f4b5e8
--- /dev/null
+++ b/vendor/spki/src/algorithm.rs
@@ -0,0 +1,194 @@
+//! X.509 `AlgorithmIdentifier`
+
+use crate::{Error, Result};
+use core::cmp::Ordering;
+use der::{
+    asn1::{AnyRef, Choice, ObjectIdentifier},
+    Decode, DecodeValue, DerOrd, Encode, EncodeValue, Header, Length, Reader, Sequence, ValueOrd,
+    Writer,
+};
+
+#[cfg(feature = "alloc")]
+use der::asn1::Any;
+
+/// X.509 `AlgorithmIdentifier` as defined in [RFC 5280 Section 4.1.1.2].
+///
+/// ```text
+/// AlgorithmIdentifier  ::=  SEQUENCE  {
+///      algorithm               OBJECT IDENTIFIER,
+///      parameters              ANY DEFINED BY algorithm OPTIONAL  }
+/// ```
+///
+/// [RFC 5280 Section 4.1.1.2]: https://tools.ietf.org/html/rfc5280#section-4.1.1.2
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
+#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord)]
+pub struct AlgorithmIdentifier<Params> {
+    /// Algorithm OID, i.e. the `algorithm` field in the `AlgorithmIdentifier`
+    /// ASN.1 schema.
+    pub oid: ObjectIdentifier,
+
+    /// Algorithm `parameters`.
+    pub parameters: Option<Params>,
+}
+
+impl<'a, Params> DecodeValue<'a> for AlgorithmIdentifier<Params>
+where
+    Params: Choice<'a>,
+{
+    fn decode_value<R: Reader<'a>>(reader: &mut R, header: Header) -> der::Result<Self> {
+        reader.read_nested(header.length, |reader| {
+            Ok(Self {
+                oid: reader.decode()?,
+                parameters: reader.decode()?,
+            })
+        })
+    }
+}
+
+impl<Params> EncodeValue for AlgorithmIdentifier<Params>
+where
+    Params: Encode,
+{
+    fn value_len(&self) -> der::Result<Length> {
+        self.oid.encoded_len()? + self.parameters.encoded_len()?
+    }
+
+    fn encode_value(&self, writer: &mut impl Writer) -> der::Result<()> {
+        self.oid.encode(writer)?;
+        self.parameters.encode(writer)?;
+        Ok(())
+    }
+}
+
+impl<'a, Params> Sequence<'a> for AlgorithmIdentifier<Params> where Params: Choice<'a> + Encode {}
+
+impl<'a, Params> TryFrom<&'a [u8]> for AlgorithmIdentifier<Params>
+where
+    Params: Choice<'a> + Encode,
+{
+    type Error = Error;
+
+    fn try_from(bytes: &'a [u8]) -> Result<Self> {
+        Ok(Self::from_der(bytes)?)
+    }
+}
+
+impl<Params> ValueOrd for AlgorithmIdentifier<Params>
+where
+    Params: DerOrd,
+{
+    fn value_cmp(&self, other: &Self) -> der::Result<Ordering> {
+        match self.oid.der_cmp(&other.oid)? {
+            Ordering::Equal => self.parameters.der_cmp(&other.parameters),
+            other => Ok(other),
+        }
+    }
+}
+
+/// `AlgorithmIdentifier` reference which has `AnyRef` parameters.
+pub type AlgorithmIdentifierRef<'a> = AlgorithmIdentifier<AnyRef<'a>>;
+
+/// `AlgorithmIdentifier` with `ObjectIdentifier` parameters.
+pub type AlgorithmIdentifierWithOid = AlgorithmIdentifier<ObjectIdentifier>;
+
+/// `AlgorithmIdentifier` reference which has `Any` parameters.
+#[cfg(feature = "alloc")]
+pub type AlgorithmIdentifierOwned = AlgorithmIdentifier<Any>;
+
+impl<Params> AlgorithmIdentifier<Params> {
+    /// Assert the `algorithm` OID is an expected value.
+    pub fn assert_algorithm_oid(&self, expected_oid: ObjectIdentifier) -> Result<ObjectIdentifier> {
+        if self.oid == expected_oid {
+            Ok(expected_oid)
+        } else {
+            Err(Error::OidUnknown { oid: expected_oid })
+        }
+    }
+}
+
+impl<'a> AlgorithmIdentifierRef<'a> {
+    /// Assert `parameters` is an OID and has the expected value.
+    pub fn assert_parameters_oid(
+        &self,
+        expected_oid: ObjectIdentifier,
+    ) -> Result<ObjectIdentifier> {
+        let actual_oid = self.parameters_oid()?;
+
+        if actual_oid == expected_oid {
+            Ok(actual_oid)
+        } else {
+            Err(Error::OidUnknown { oid: expected_oid })
+        }
+    }
+
+    /// Assert the values of the `algorithm` and `parameters` OIDs.
+    pub fn assert_oids(
+        &self,
+        algorithm: ObjectIdentifier,
+        parameters: ObjectIdentifier,
+    ) -> Result<()> {
+        self.assert_algorithm_oid(algorithm)?;
+        self.assert_parameters_oid(parameters)?;
+        Ok(())
+    }
+
+    /// Get the `parameters` field as an [`AnyRef`].
+    ///
+    /// Returns an error if `parameters` are `None`.
+    pub fn parameters_any(&self) -> Result<AnyRef<'a>> {
+        self.parameters.ok_or(Error::AlgorithmParametersMissing)
+    }
+
+    /// Get the `parameters` field as an [`ObjectIdentifier`].
+    ///
+    /// Returns an error if it is absent or not an OID.
+    pub fn parameters_oid(&self) -> Result<ObjectIdentifier> {
+        Ok(ObjectIdentifier::try_from(self.parameters_any()?)?)
+    }
+
+    /// Convert to a pair of [`ObjectIdentifier`]s.
+    ///
+    /// This method is helpful for decomposing in match statements. Note in
+    /// particular that `NULL` parameters are treated the same as missing
+    /// parameters.
+    ///
+    /// Returns an error if parameters are present but not an OID.
+    pub fn oids(&self) -> der::Result<(ObjectIdentifier, Option<ObjectIdentifier>)> {
+        Ok((
+            self.oid,
+            match self.parameters {
+                None => None,
+                Some(p) => match p {
+                    AnyRef::NULL => None,
+                    _ => Some(p.decode_as::<ObjectIdentifier>()?),
+                },
+            },
+        ))
+    }
+}
+
+#[cfg(feature = "alloc")]
+mod allocating {
+    use super::*;
+    use der::referenced::*;
+
+    impl<'a> RefToOwned<'a> for AlgorithmIdentifierRef<'a> {
+        type Owned = AlgorithmIdentifierOwned;
+        fn ref_to_owned(&self) -> Self::Owned {
+            AlgorithmIdentifier {
+                oid: self.oid,
+                parameters: self.parameters.ref_to_owned(),
+            }
+        }
+    }
+
+    impl OwnedToRef for AlgorithmIdentifierOwned {
+        type Borrowed<'a> = AlgorithmIdentifierRef<'a>;
+        fn owned_to_ref(&self) -> Self::Borrowed<'_> {
+            AlgorithmIdentifier {
+                oid: self.oid,
+                parameters: self.parameters.owned_to_ref(),
+            }
+        }
+    }
+}