Enum trust_dns_proto::rr::domain::usage::ResolverUsage
source · [−]pub enum ResolverUsage {
Normal,
Loopback,
LinkLocal,
NxDomain,
}
Expand description
Name Resolution APIs and Libraries:
Are writers of name resolution APIs and libraries expected to make their software recognize these names as special and treat them differently? If so, how?
Variants
Normal
Name resolution APIs and libraries SHOULD NOT recognize these names as special and SHOULD NOT treat them differently. Name resolution APIs SHOULD send queries for these names to their configured caching DNS server(s).
Name resolution APIs and libraries SHOULD NOT recognize test names as special and SHOULD NOT treat them differently. Name resolution APIs SHOULD send queries for test names to their configured caching DNS server(s).
Name resolution APIs and libraries SHOULD NOT recognize example names as special and SHOULD NOT treat them differently. Name resolution APIs SHOULD send queries for example names to their configured caching DNS server(s).
Loopback
Name resolution APIs and libraries SHOULD recognize localhost names as special and SHOULD always return the IP loopback address for address queries and negative responses for all other query types. Name resolution APIs SHOULD NOT send queries for localhost names to their configured caching DNS server(s).
LinkLocal
Link local, generally for mDNS
Any DNS query for a name ending with “.local.” MUST be sent to the mDNS IPv4 link-local multicast address 224.0.0.251 (or its IPv6 equivalent FF02::FB). The design rationale for using a fixed multicast address instead of selecting from a range of multicast addresses using a hash function is discussed in Appendix B. Implementers MAY choose to look up such names concurrently via other mechanisms (e.g., Unicast DNS) and coalesce the results in some fashion. Implementers choosing to do this should be aware of the potential for user confusion when a given name can produce different results depending on external network conditions (such as, but not limited to, which name lookup mechanism responds faster).
NxDomain
Name resolution APIs and libraries SHOULD recognize “invalid” names as special and SHOULD always return immediate negative responses. Name resolution APIs SHOULD NOT send queries for “invalid” names to their configured caching DNS server(s).
Trait Implementations
sourceimpl Clone for ResolverUsage
impl Clone for ResolverUsage
sourcefn clone(&self) -> ResolverUsage
fn clone(&self) -> ResolverUsage
Returns a copy of the value. Read more
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from source
. Read more
sourceimpl PartialEq<ResolverUsage> for ResolverUsage
impl PartialEq<ResolverUsage> for ResolverUsage
impl Copy for ResolverUsage
impl Eq for ResolverUsage
impl StructuralEq for ResolverUsage
impl StructuralPartialEq for ResolverUsage
Auto Trait Implementations
impl RefUnwindSafe for ResolverUsage
impl Send for ResolverUsage
impl Sync for ResolverUsage
impl Unpin for ResolverUsage
impl UnwindSafe for ResolverUsage
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<T> ToOwned for T where
T: Clone,
impl<T> ToOwned for T where
T: Clone,
type Owned = T
type Owned = T
The resulting type after obtaining ownership.
sourcefn clone_into(&self, target: &mut T)
fn clone_into(&self, target: &mut T)
toowned_clone_into
)Uses borrowed data to replace owned data, usually by cloning. Read more