asn1_rs/asn1_types/
octetstring.rs

1use crate::*;
2use alloc::borrow::Cow;
3use core::convert::TryFrom;
4
5/// ASN.1 `OCTETSTRING` type
6#[derive(Debug, PartialEq, Eq)]
7pub struct OctetString<'a> {
8    data: Cow<'a, [u8]>,
9}
10
11impl<'a> OctetString<'a> {
12    pub const fn new(s: &'a [u8]) -> Self {
13        OctetString {
14            data: Cow::Borrowed(s),
15        }
16    }
17
18    /// Get the bytes representation of the *content*
19    pub fn as_cow(&'a self) -> &Cow<'a, [u8]> {
20        &self.data
21    }
22
23    /// Get the bytes representation of the *content*
24    pub fn into_cow(self) -> Cow<'a, [u8]> {
25        self.data
26    }
27}
28
29impl<'a> AsRef<[u8]> for OctetString<'a> {
30    fn as_ref(&self) -> &[u8] {
31        &self.data
32    }
33}
34
35impl<'a> From<&'a [u8]> for OctetString<'a> {
36    fn from(b: &'a [u8]) -> Self {
37        OctetString {
38            data: Cow::Borrowed(b),
39        }
40    }
41}
42
43impl<'a> TryFrom<Any<'a>> for OctetString<'a> {
44    type Error = Error;
45
46    fn try_from(any: Any<'a>) -> Result<OctetString<'a>> {
47        TryFrom::try_from(&any)
48    }
49}
50
51impl<'a, 'b> TryFrom<&'b Any<'a>> for OctetString<'a> {
52    type Error = Error;
53
54    fn try_from(any: &'b Any<'a>) -> Result<OctetString<'a>> {
55        any.tag().assert_eq(Self::TAG)?;
56        Ok(OctetString {
57            data: Cow::Borrowed(any.data),
58        })
59    }
60}
61
62impl<'a> CheckDerConstraints for OctetString<'a> {
63    fn check_constraints(any: &Any) -> Result<()> {
64        // X.690 section 10.2
65        any.header.assert_primitive()?;
66        Ok(())
67    }
68}
69
70impl DerAutoDerive for OctetString<'_> {}
71
72impl<'a> Tagged for OctetString<'a> {
73    const TAG: Tag = Tag::OctetString;
74}
75
76#[cfg(feature = "std")]
77impl ToDer for OctetString<'_> {
78    fn to_der_len(&self) -> Result<usize> {
79        let sz = self.data.len();
80        if sz < 127 {
81            // 1 (class+tag) + 1 (length) + len
82            Ok(2 + sz)
83        } else {
84            // 1 (class+tag) + n (length) + len
85            let n = Length::Definite(sz).to_der_len()?;
86            Ok(1 + n + sz)
87        }
88    }
89
90    fn write_der_header(&self, writer: &mut dyn std::io::Write) -> SerializeResult<usize> {
91        let header = Header::new(
92            Class::Universal,
93            false,
94            Self::TAG,
95            Length::Definite(self.data.len()),
96        );
97        header.write_der_header(writer).map_err(Into::into)
98    }
99
100    fn write_der_content(&self, writer: &mut dyn std::io::Write) -> SerializeResult<usize> {
101        writer.write(&self.data).map_err(Into::into)
102    }
103}
104
105impl<'a> TryFrom<Any<'a>> for &'a [u8] {
106    type Error = Error;
107
108    fn try_from(any: Any<'a>) -> Result<&'a [u8]> {
109        any.tag().assert_eq(Self::TAG)?;
110        let s = OctetString::try_from(any)?;
111        match s.data {
112            Cow::Borrowed(s) => Ok(s),
113            Cow::Owned(_) => Err(Error::LifetimeError),
114        }
115    }
116}
117
118impl<'a> CheckDerConstraints for &'a [u8] {
119    fn check_constraints(any: &Any) -> Result<()> {
120        // X.690 section 10.2
121        any.header.assert_primitive()?;
122        Ok(())
123    }
124}
125
126impl DerAutoDerive for &'_ [u8] {}
127
128impl<'a> Tagged for &'a [u8] {
129    const TAG: Tag = Tag::OctetString;
130}
131
132#[cfg(feature = "std")]
133impl ToDer for &'_ [u8] {
134    fn to_der_len(&self) -> Result<usize> {
135        let header = Header::new(
136            Class::Universal,
137            false,
138            Self::TAG,
139            Length::Definite(self.len()),
140        );
141        Ok(header.to_der_len()? + self.len())
142    }
143
144    fn write_der_header(&self, writer: &mut dyn std::io::Write) -> SerializeResult<usize> {
145        let header = Header::new(
146            Class::Universal,
147            false,
148            Self::TAG,
149            Length::Definite(self.len()),
150        );
151        header.write_der_header(writer).map_err(Into::into)
152    }
153
154    fn write_der_content(&self, writer: &mut dyn std::io::Write) -> SerializeResult<usize> {
155        writer.write(self).map_err(Into::into)
156    }
157}
asn1_rs/asn1_types/octetstring.rs

asn1_rs/asn1_types/
octetstring.rs
