simple_dns/dns/rdata/
ds.rs

1use crate::{bytes_buffer::BytesBuffer, dns::WireFormat, lib::Cow, lib::Write};
2
3use super::RR;
4
5/// A DS record see [rfc4034](https://www.rfc-editor.org/rfc/rfc4034#section-5)
6#[derive(Debug, PartialEq, Eq, Hash, Clone)]
7pub struct DS<'a> {
8    /// The key tag is a 16-bit value used to identify the DNSKEY record referenced by this DS record
9    pub key_tag: u16,
10    /// The algorithm number identifying the cryptographic algorithm used to create the signature
11    pub algorithm: u8,
12    /// The digest type number identifying the cryptographic hash algorithm used to create the digest
13    pub digest_type: u8,
14    /// The digest value calculated over the referenced DNSKEY record
15    pub digest: Cow<'a, [u8]>,
16}
17
18impl RR for DS<'_> {
19    const TYPE_CODE: u16 = 43;
20}
21
22impl<'a> WireFormat<'a> for DS<'a> {
23    const MINIMUM_LEN: usize = 4;
24
25    fn parse(data: &mut BytesBuffer<'a>) -> crate::Result<Self>
26    where
27        Self: Sized,
28    {
29        let key_tag = data.get_u16()?;
30        let algorithm = data.get_u8()?;
31        let digest_type = data.get_u8()?;
32        let digest = Cow::Borrowed(data.get_remaining());
33
34        Ok(Self {
35            key_tag,
36            algorithm,
37            digest_type,
38            digest,
39        })
40    }
41
42    fn write_to<T: Write>(&self, out: &mut T) -> crate::Result<()> {
43        out.write_all(&self.key_tag.to_be_bytes())?;
44        out.write_all(&[self.algorithm, self.digest_type])?;
45        out.write_all(&self.digest)?;
46
47        Ok(())
48    }
49
50    fn len(&self) -> usize {
51        self.digest.len() + Self::MINIMUM_LEN
52    }
53}
54
55impl DS<'_> {
56    /// Transforms the inner data into its owned type
57    pub fn into_owned<'b>(self) -> DS<'b> {
58        DS {
59            key_tag: self.key_tag,
60            algorithm: self.algorithm,
61            digest_type: self.digest_type,
62            digest: Cow::Owned(self.digest.into_owned()),
63        }
64    }
65}
66
67#[cfg(test)]
68mod tests {
69    use super::*;
70    use crate::lib::{vec, Vec};
71
72    #[test]
73    fn parse_and_write_ds() {
74        let key_tag = 12345u16;
75        let algorithm = 8u8;
76        let digest_type = 2u8;
77        let digest = vec![1, 2, 3, 4, 5];
78        let rdata = DS {
79            key_tag,
80            algorithm,
81            digest_type,
82            digest: Cow::Owned(digest),
83        };
84        let mut writer = Vec::new();
85        rdata.write_to(&mut writer).unwrap();
86        let rdata = DS::parse(&mut (&writer[..]).into()).unwrap();
87        assert_eq!(rdata.key_tag, key_tag);
88        assert_eq!(rdata.algorithm, algorithm);
89        assert_eq!(rdata.digest_type, digest_type);
90        assert_eq!(&*rdata.digest, &[1, 2, 3, 4, 5]);
91    }
92
93    #[test]
94    #[cfg(feature = "std")]
95    fn parse_sample() -> Result<(), Box<dyn std::error::Error>> {
96        use crate::{rdata::RData, ResourceRecord};
97        let sample_file = std::fs::read("samples/zonefile/DS.sample")?;
98
99        let sample_rdata = match ResourceRecord::parse(&mut (&sample_file[..]).into())?.rdata {
100            RData::DS(rdata) => rdata,
101            _ => unreachable!(),
102        };
103
104        assert_eq!(sample_rdata.algorithm, 5);
105        assert_eq!(sample_rdata.digest_type, 1);
106        assert_eq!(sample_rdata.key_tag, 60485);
107        assert_eq!(
108            *sample_rdata.digest,
109            *b"\x2B\xB1\x83\xAF\x5F\x22\x58\x81\x79\xA5\x3B\x0A\x98\x63\x1F\xAD\x1A\x29\x21\x18"
110        );
111
112        Ok(())
113    }
114}
simple_dns/dns/rdata/ds.rs

simple_dns/dns/rdata/
ds.rs
