1 //! PKCS#8 version identifier.
2 
3 use crate::Error;
4 use der::{Decode, Encode, FixedTag, Reader, Tag, Writer};
5 
6 /// Version identifier for PKCS#8 documents.
7 ///
8 /// (RFC 5958 designates `0` and `1` as the only valid versions for PKCS#8 documents)
9 #[derive(Clone, Debug, Copy, PartialEq, Eq)]
10 pub enum Version {
11     /// Denotes PKCS#8 v1: no public key field.
12     V1 = 0,
13 
14     /// Denotes PKCS#8 v2: `OneAsymmetricKey` with public key field.
15     V2 = 1,
16 }
17 
18 impl Version {
19     /// Is this version expected to have a public key?
has_public_key(self) -> bool20     pub fn has_public_key(self) -> bool {
21         match self {
22             Version::V1 => false,
23             Version::V2 => true,
24         }
25     }
26 }
27 
28 impl<'a> Decode<'a> for Version {
decode<R: Reader<'a>>(decoder: &mut R) -> der::Result<Self>29     fn decode<R: Reader<'a>>(decoder: &mut R) -> der::Result<Self> {
30         Version::try_from(u8::decode(decoder)?).map_err(|_| Self::TAG.value_error())
31     }
32 }
33 
34 impl Encode for Version {
encoded_len(&self) -> der::Result<der::Length>35     fn encoded_len(&self) -> der::Result<der::Length> {
36         der::Length::from(1u8).for_tlv()
37     }
38 
encode(&self, writer: &mut impl Writer) -> der::Result<()>39     fn encode(&self, writer: &mut impl Writer) -> der::Result<()> {
40         u8::from(*self).encode(writer)
41     }
42 }
43 
44 impl From<Version> for u8 {
from(version: Version) -> Self45     fn from(version: Version) -> Self {
46         version as u8
47     }
48 }
49 
50 impl TryFrom<u8> for Version {
51     type Error = Error;
try_from(byte: u8) -> Result<Version, Error>52     fn try_from(byte: u8) -> Result<Version, Error> {
53         match byte {
54             0 => Ok(Version::V1),
55             1 => Ok(Version::V2),
56             _ => Err(Self::TAG.value_error().into()),
57         }
58     }
59 }
60 
61 impl FixedTag for Version {
62     const TAG: Tag = Tag::Integer;
63 }
64