+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+/// A mask used in [`NSec`] and [`NSec3`] records which indicates the resource record types which
+/// exist at the (hash of the) name described in [`Record::name`].
+pub struct NSecTypeMask([u8; 8192]);
+impl NSecTypeMask {
+ /// Constructs a new, empty, type mask.
+ pub fn new() -> Self { Self([0; 8192]) }
+ /// Builds a new type mask with the given types set
+ pub fn from_types(types: &[u16]) -> Self {
+ let mut flags = [0; 8192];
+ for t in types {
+ flags[*t as usize >> 3] |= 1 << (7 - (*t as usize % 8));
+ }
+ let res = Self(flags);
+ for t in types {
+ debug_assert!(res.contains_type(*t));
+ }
+ res
+ }
+ /// Checks if the given type (from [`Record::ty`]) is set, indicating a record of this type
+ /// exists.
+ pub fn contains_type(&self, ty: u16) -> bool {
+ let f = self.0[(ty >> 3) as usize];
+ // DNSSEC's bit fields are in wire order, so the high bit is type 0, etc.
+ f & (1 << (7 - (ty % 8))) != 0
+ }
+ fn write_json(&self, s: &mut String) {
+ *s += "[";
+ let mut have_written = false;
+ for (idx, mask) in self.0.iter().enumerate() {
+ if *mask == 0 { continue; }
+ for b in 0..8 {
+ if *mask & (1 << b) != 0 {
+ if have_written {
+ *s += ",";
+ }
+ have_written = true;
+ let ty = ((idx as u16) << 3) | (7 - b);
+ match RR::ty_to_rr_name(ty) {
+ Some(name) => write!(s, "\"{}\"", name).expect("Writes to a string shouldn't fail"),
+ _ => write!(s, "{}", ty).expect("Writes to a string shouldn't fail"),
+ }
+ }
+ }
+ }
+ *s += "]";
+ }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+/// A Next Secure Record resource record. This indicates a range of possible names for which there
+/// is no such record.
+pub struct NSec {
+ /// The name this record is at.
+ pub name: Name,
+ /// The next name which contains a record. There are no names between `name` and
+ /// [`Self::next_name`].
+ pub next_name: Name,
+ /// The set of record types which exist at `name`. Any other record types do not exist at
+ /// `name`.
+ pub types: NSecTypeMask,
+}
+impl StaticRecord for NSec {
+ const TYPE: u16 = 47;
+ fn name(&self) -> &Name { &self.name }
+ fn json(&self) -> String {
+ let mut out = String::with_capacity(256 + self.next_name.len());
+ write!(&mut out,
+ "{{\"type\":\"nsec\",\"name\":\"{}\",\"next_name\":\"{}\",\"types\":",
+ self.name.0, self.next_name.0,
+ ).expect("Write to a String shouldn't fail");
+ self.types.write_json(&mut out);
+ out += "}";
+ out
+ }
+ fn read_from_data(name: Name, mut data: &[u8], wire_packet: &[u8]) -> Result<Self, ()> {
+ let res = NSec {
+ name, next_name: read_wire_packet_name(&mut data, wire_packet)?,
+ types: NSecTypeMask(read_nsec_types_bitmap(&mut data)?),
+ };
+ debug_assert!(data.is_empty());
+ Ok(res)
+ }
+ fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
+ let len = name_len(&self.next_name) + nsec_types_bitmap_len(&self.types.0);
+ out.extend_from_slice(&len.to_be_bytes());
+ write_name(out, &self.next_name);
+ write_nsec_types_bitmap(out, &self.types.0);
+ }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+/// A Next Secure Record resource record. This indicates a range of possible names for which there
+/// is no such record.
+pub struct NSec3 {
+ /// The name this record is at.
+ pub name: Name,
+ /// The hash algorithm used to hash the `name` and [`Self::next_name_hash`]. Currently only 1
+ /// (SHA-1) is defined.
+ pub hash_algo: u8,
+ /// Flags for this record. Currently only bit 0 (the "opt-out" bit) is defined.
+ pub flags: u8,
+ /// The number of hash iterations required.
+ ///
+ /// As of RFC 9276 this MUST be set to 0, but sadly is often still set higher in the wild. A
+ /// hard cap is applied in validation.
+ pub hash_iterations: u16,
+ /// The salt included in the hash.
+ ///
+ /// As of RFC 9276 this SHOULD be empty, but often isn't in the wild.
+ pub salt: Vec<u8>,
+ /// The hash of the next name which contains a record. There are no records who's name's hash
+ /// lies between `name` and [`Self::next_name_hash`].
+ pub next_name_hash: Vec<u8>,
+ /// The set of record types which exist at `name`. Any other record types do not exist at
+ /// `name`.
+ pub types: NSecTypeMask,
+}
+impl StaticRecord for NSec3 {
+ const TYPE: u16 = 50;
+ fn name(&self) -> &Name { &self.name }
+ fn json(&self) -> String {
+ let mut out = String::with_capacity(256);
+ write!(&mut out,
+ "{{\"type\":\"nsec3\",\"name\":\"{}\",\"hash_algo\":{},\"flags\":{},\"hash_iterations\":{},\"salt\":{:?},\"next_name_hash\":{:?},\"types\":",
+ self.name.0, self.hash_algo, self.flags, self.hash_iterations, &self.salt[..], &self.next_name_hash[..]
+ ).expect("Write to a String shouldn't fail");
+ self.types.write_json(&mut out);
+ out += "}";
+ out
+ }
+ fn read_from_data(name: Name, mut data: &[u8], _wire_packet: &[u8]) -> Result<Self, ()> {
+ let res = NSec3 {
+ name, hash_algo: read_u8(&mut data)?, flags: read_u8(&mut data)?,
+ hash_iterations: read_u16(&mut data)?, salt: read_u8_len_prefixed_bytes(&mut data)?,
+ next_name_hash: read_u8_len_prefixed_bytes(&mut data)?,
+ types: NSecTypeMask(read_nsec_types_bitmap(&mut data)?),
+ };
+ debug_assert!(data.is_empty());
+ Ok(res)
+ }
+ fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
+ let len = 4 + 2 + self.salt.len() as u16 + self.next_name_hash.len() as u16 +
+ nsec_types_bitmap_len(&self.types.0);
+ out.extend_from_slice(&len.to_be_bytes());
+ out.extend_from_slice(&self.hash_algo.to_be_bytes());
+ out.extend_from_slice(&self.flags.to_be_bytes());
+ out.extend_from_slice(&self.hash_iterations.to_be_bytes());
+ out.extend_from_slice(&(self.salt.len() as u8).to_be_bytes());
+ out.extend_from_slice(&self.salt);
+ out.extend_from_slice(&(self.next_name_hash.len() as u8).to_be_bytes());
+ out.extend_from_slice(&self.next_name_hash);
+ write_nsec_types_bitmap(out, &self.types.0);
+ }
+}
+