dns_message_parser/rr/edns/
rfc_7871.rs

1use crate::rr::{Address, AddressError};
2use std::cmp::max;
3use std::fmt::{Display, Formatter, Result as FmtResult};
4
5#[derive(Debug, PartialEq, Clone, Eq, Hash)]
6pub struct ECS {
7    source_prefix_length: u8,
8    scope_prefix_length: u8,
9    address: Address,
10}
11
12macro_rules! setter {
13    ($(#[$doc_comment:meta])* $method:ident, $member:ident, $type:ident) => {
14        $(#[$doc_comment])*
15        pub fn $method(&mut self, new_value: $type) -> Result<(), AddressError> {
16            let previous = self.$member.clone();
17            self.$member = new_value;
18            match self.check_addr() {
19                Ok(()) => Ok(()),
20                Err(address_error) => {
21                    self.$member = previous;
22                    Err(address_error)
23                }
24            }
25        }
26    };
27}
28
29impl ECS {
30    fn check_addr(&self) -> Result<(), AddressError> {
31        let prefix_length = self.get_prefix_length();
32        self.address.check_prefix(prefix_length)
33    }
34
35    pub fn new(
36        source_prefix_length: u8,
37        scope_prefix_length: u8,
38        address: Address,
39    ) -> Result<ECS, AddressError> {
40        let ecs = ECS {
41            source_prefix_length,
42            scope_prefix_length,
43            address,
44        };
45
46        ecs.check_addr()?;
47
48        Ok(ecs)
49    }
50
51    /// Returns the current source prefix length.
52    #[inline]
53    pub const fn get_source_prefix_length(&self) -> u8 {
54        self.source_prefix_length
55    }
56
57    setter!(
58        /// Try to set the source prefix length.
59        ///
60        /// Returns `Ok()` if the length fit in the current address as network mask, otherwise
61        /// returns [`AddressError`] and the value is not changed.
62        ///
63        /// [`AddressError`]: crate::rr::AddressError
64        set_source_prefix_length,
65        source_prefix_length,
66        u8
67    );
68
69    /// Returns the current scope prefix length.
70    #[inline]
71    pub const fn get_scope_prefix_length(&self) -> u8 {
72        self.scope_prefix_length
73    }
74
75    setter!(
76        /// Try to set the scope prefix length.
77        ///
78        /// Returns `Ok()` if the length fit in the current address as network mask, otherwise
79        /// returns [`AddressError`] and the value is not changed.
80        ///
81        /// [`AddressError`]: crate::rr::AddressError
82        set_scope_prefix_length,
83        scope_prefix_length,
84        u8
85    );
86
87    /// Returns the current address.
88    #[inline]
89    pub const fn get_address(&self) -> &Address {
90        &self.address
91    }
92
93    setter!(
94        /// Try to set the scope prefix length.
95        ///
96        /// Returns `Ok()` if the current and scope prefix length fits in the new address as
97        /// network mask , otherwise returns [`AddressError`] and the value is not changed.
98        ///
99        /// [`AddressError`]: crate::rr::AddressError
100        set_address,
101        address,
102        Address
103    );
104
105    /// Returns the prefix length of the address.
106    ///
107    /// It the max value of the `source_prefix_length` and `scope_prefix_length`.
108    #[inline]
109    pub fn get_prefix_length(&self) -> u8 {
110        max(self.source_prefix_length, self.scope_prefix_length)
111    }
112}
113
114impl Display for ECS {
115    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
116        write!(
117            f,
118            "ECS {} {} {}",
119            self.source_prefix_length, self.scope_prefix_length, self.address
120        )
121    }
122}
dns_message_parser/rr/edns/rfc_7871.rs

dns_message_parser/rr/edns/
rfc_7871.rs
