simple_dns/dns/rdata/
caa.rs

1use crate::dns::{CharacterString, WireFormat};
2
3use super::RR;
4
5/// RFC 8659: Allow domain name holders to indicate whether they are authorized to issue digital certificates for particular domain name
6/// Used as a security policy for certificate authorities
7/// This implementation does not validate the tag or value; it splits based on packet byte structure
8#[derive(Debug, PartialEq, Eq, Hash, Clone)]
9pub struct CAA<'a> {
10    /// Critical or noncritical indicator
11    pub flag: u8,
12    /// Property described in the VALUE field. One of `issue`, `issuewild`, or `iodef`
13    pub tag: CharacterString<'a>,
14    /// Value associated with property tag
15    pub value: CharacterString<'a>,
16}
17
18impl<'a> RR for CAA<'a> {
19    const TYPE_CODE: u16 = 257;
20}
21
22impl<'a> CAA<'a> {
23    /// Transforms the inner data into it owned type
24    pub fn into_owned<'b>(self) -> CAA<'b> {
25        CAA {
26            flag: self.flag,
27            tag: self.tag.into_owned(),
28            value: self.value.into_owned(),
29        }
30    }
31}
32
33impl<'a> WireFormat<'a> for CAA<'a> {
34    fn parse(data: &'a [u8], position: &mut usize) -> crate::Result<Self>
35    where
36        Self: Sized,
37    {
38        let flag = u8::from_be_bytes(data[*position..*position + 1].try_into()?);
39        *position += 1;
40        let tag = CharacterString::parse(data, position)?;
41        let value = CharacterString::parse(data, position)?;
42
43        Ok(Self { flag, tag, value })
44    }
45
46    fn write_to<T: std::io::Write>(&self, out: &mut T) -> crate::Result<()> {
47        out.write_all(&self.flag.to_be_bytes())?;
48        self.tag.write_to(out)?;
49        self.value.write_to(out)
50    }
51
52    fn len(&self) -> usize {
53        self.tag.len() + self.value.len() + 1
54    }
55}
56
57#[cfg(test)]
58mod tests {
59    use super::*;
60
61    #[test]
62    fn parse_and_write_caa() {
63        let caa = CAA {
64            flag: 0,
65            tag: CharacterString::new(b"issue").unwrap(),
66            value: CharacterString::new(b"\"example.org").unwrap(),
67        };
68
69        let mut data = Vec::new();
70        assert!(caa.write_to(&mut data).is_ok());
71
72        let caa = CAA::parse(&data, &mut 0);
73        assert!(caa.is_ok());
74        let caa = caa.unwrap();
75
76        assert_eq!(data.len(), caa.len());
77        assert_eq!(0, caa.flag);
78        assert_eq!("issue", caa.tag.to_string());
79        assert_eq!("\"example.org", caa.value.to_string());
80    }
81}
simple_dns/dns/rdata/caa.rs

simple_dns/dns/rdata/
caa.rs
