simple_dns/dns/rdata/
dhcid.rs

1use crate::{bytes_buffer::BytesBuffer, dns::WireFormat};
2use std::borrow::Cow;
3
4use super::RR;
5
6/// A DHCID record see [rfc4701](https://datatracker.ietf.org/doc/html/rfc4701)
7#[derive(Debug, PartialEq, Eq, Hash, Clone)]
8pub struct DHCID<'a> {
9    /// Identifier type code
10    pub identifier: u16,
11    /// Digest type code
12    pub digest_type: u8,
13    /// Digest (length depends on digest type)
14    pub digest: Cow<'a, [u8]>,
15}
16
17impl RR for DHCID<'_> {
18    const TYPE_CODE: u16 = 49;
19}
20
21impl<'a> WireFormat<'a> for DHCID<'a> {
22    const MINIMUM_LEN: usize = 3;
23
24    fn parse(data: &mut BytesBuffer<'a>) -> crate::Result<Self>
25    where
26        Self: Sized,
27    {
28        let identifier = data.get_u16()?;
29        let digest_type = data.get_u8()?;
30        let digest = Cow::Borrowed(data.get_remaining());
31
32        Ok(Self {
33            identifier,
34            digest_type,
35            digest,
36        })
37    }
38
39    fn write_to<T: std::io::Write>(&self, out: &mut T) -> crate::Result<()> {
40        out.write_all(&self.identifier.to_be_bytes())?;
41        out.write_all(&[self.digest_type])?;
42        out.write_all(&self.digest)?;
43
44        Ok(())
45    }
46
47    fn len(&self) -> usize {
48        self.digest.len() + Self::MINIMUM_LEN
49    }
50}
51
52impl DHCID<'_> {
53    /// Transforms the inner data into its owned type
54    pub fn into_owned<'b>(self) -> DHCID<'b> {
55        DHCID {
56            identifier: self.identifier,
57            digest_type: self.digest_type,
58            digest: Cow::Owned(self.digest.into_owned()),
59        }
60    }
61}
62
63#[cfg(test)]
64mod tests {
65    use crate::{rdata::RData, ResourceRecord};
66
67    use super::*;
68
69    #[test]
70    fn parse_and_write_dhcid() {
71        let ds = DHCID {
72            identifier: 0,
73            digest_type: 0,
74            digest: Cow::Borrowed(&[0, 0, 0, 0]),
75        };
76
77        let mut data = Vec::new();
78        ds.write_to(&mut data).unwrap();
79
80        let ds = DHCID::parse(&mut (&data[..]).into()).unwrap();
81        assert_eq!(ds.identifier, 0);
82        assert_eq!(ds.digest_type, 0);
83        assert_eq!(ds.digest, Cow::Borrowed(&[0, 0, 0, 0]));
84    }
85
86    #[test]
87    fn parse_sample() -> Result<(), Box<dyn std::error::Error>> {
88        let sample_file = std::fs::read("samples/zonefile/DHCID.sample")?;
89
90        let sample_rdata = match ResourceRecord::parse(&mut (&sample_file[..]).into())?.rdata {
91            RData::DHCID(rdata) => rdata,
92            _ => unreachable!(),
93        };
94
95        assert_eq!(sample_rdata.identifier, 0x0002);
96        assert_eq!(sample_rdata.digest_type, 0x01);
97        assert_eq!(*sample_rdata.digest, *b"\x63\x6f\xc0\xb8\x27\x1c\x82\x82\x5b\xb1\xac\x5c\x41\xcf\x53\x51\xaa\x69\xb4\xfe\xbd\x94\xe8\xf1\x7c\xdb\x95\x00\x0d\xa4\x8c\x40");
98
99        Ok(())
100    }
101}