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resolver

package

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Versions in this module

v0

v0.28.0

Aug 25, 2026

Changes in this version

+ var ErrDNSNoData = errDNSNoData

+ var ErrDOHProtocolIncompatible = errors.New("DoH endpoint does not support DNS wire messages")

+ var ErrHTTPSRecordsUnavailable = errors.New("HTTPS record discovery is unavailable")

+ func ECHPublicName(value []byte) (string, error)

+ func EncodeQuery(name string, typ uint16) ([]byte, uint16, error)

+ func EncodeQueryWithID(id uint16, name string, typ uint16) ([]byte, uint16, error)

+ func IsAuthenticatedDiscoveryFailure(err error) bool

+ func MayDowngrade(err error) bool

+ func RCodeName(code uint16) string

+ func RaceCandidates[T any](ctx context.Context, candidates []net.IPAddr, ...) (T, error)

+ func RecordAddress(record Record) net.IP

+ func SupportedECHConfigList(value []byte) ([]byte, error)

+ func ValidateRData(typ uint16, rdata []byte) error

+ func ValidateSVCBRRSet(records []Record) error

+ type AddressLookup func(context.Context, string) ([]net.IPAddr, error)

+ type BootstrapFunc func(context.Context, string) ([]net.IPAddr, error)

type Config

+ Bootstrap BootstrapFunc

+ CACerts []*x509.Certificate

+ ClientCert *tls.Certificate

+ DialContext DialContextFunc

+ Endpoint *Endpoint

+ Insecure bool

+ Proxy func(*http.Request) (*url.URL, error)

+ RoundTripper http.RoundTripper

+ SystemLookupIPAddr func(context.Context, string) ([]net.IPAddr, error)

+ SystemPolicy *SystemResolverPolicy

+ TLSConfig *tls.Config

+ TLSMax uint16

+ TLSMin uint16

type DNSRecord

+ TTLPresent bool

+ type DOHClient struct

+ func NewDOHClient(cfg DOHConfig) (*DOHClient, error)

+ func (c *DOHClient) Close() error

+ func (c *DOHClient) LookupInspectionType(ctx context.Context, host, dnsType string, answerType int) ([]DOHRecord, error)

+ func (c *DOHClient) LookupType(ctx context.Context, host, dnsType string, answerType int) ([]DNSRecord, error)

+ type DOHConfig struct

+ Bootstrap BootstrapFunc

+ CACerts []*x509.Certificate

+ ClientCert *tls.Certificate

+ DialContext DialContextFunc

+ Endpoint *Endpoint

+ Insecure bool

+ Proxy func(*http.Request) (*url.URL, error)

+ RoundTripper http.RoundTripper

+ RoundTripperOwned bool

+ ServerURL *url.URL

+ TLSConfig *tls.Config

+ TLSMax uint16

+ TLSMin uint16

+ Timeout time.Duration

+ type DOHRecord struct

+ Data string

+ Record Record

+ TTLPresent bool

+ type DialContextFunc func(context.Context, string, string) (net.Conn, error)

+ type DiscoveryError struct

+ Err error

+ Kind DiscoveryFailureKind

+ func (e *DiscoveryError) Error() string

+ func (e *DiscoveryError) Unwrap() error

+ type DiscoveryFailureKind uint8

+ const DiscoveryFailureAuthenticated

+ const DiscoveryFailureNODATA

+ const DiscoveryFailureNXDOMAIN

+ const DiscoveryFailureUnauthenticated

+ const DiscoveryFailureUnknown

+ func DiscoveryFailure(err error) DiscoveryFailureKind

+ type DoQClient struct

+ func NewDoQClient(ctx context.Context, cfg DoQConfig) (*DoQClient, error)

+ func (c *DoQClient) Close() error

+ func (c *DoQClient) Query(ctx context.Context, name string, typ uint16) (*Message, error)

+ func (c *DoQClient) QueryMany(ctx context.Context, queries []Question) ([]*Message, error)

+ type DoQConfig = StreamConfig

+ type ECHConfigListInfo struct

+ ConfigurationCount int

+ Raw []byte

+ Supported []byte

+ UnsupportedCount int

+ func ValidateECHConfigList(value []byte) (ECHConfigListInfo, error)

type Endpoint

+ BootstrapAddrs []net.IP

+ ConnectHost string

+ Display string

+ Path string

+ RawPath string

+ RawQuery string

+ Security Security

+ TLSServerName string

+ Transport Transport

+ VerifyTLS bool

+ func ParseEndpoint(value string) (*Endpoint, error)

+ func ParseEndpointURL(value string, allowInsecureHTTPS bool) (*Endpoint, error)

+ func (e *Endpoint) Address() string

+ func (e *Endpoint) String() string

+ func (e *Endpoint) URL() *url.URL

+ type HTTPSDiscovery struct

+ Authenticated bool

+ Candidates []ServiceCandidate

+ EffectiveTarget Name

+ FallbackAddresses []net.IPAddr

+ FallbackPort uint16

+ Origin Name

+ Security Security

+ TTL uint32

+ TTLPresent bool

+ func ResolveHTTPS(ctx context.Context, host string, records HTTPSRecordLookup, ...) (HTTPSDiscovery, error)

+ type HTTPSRecordLookup func(context.Context, string) ([]Record, error)

+ type Header struct

+ Authoritative bool

+ ID uint16

+ Opcode uint8

+ RCode uint16

+ RecursionAvailable bool

+ RecursionDesired bool

+ Response bool

+ Truncated bool

+ type Message struct

+ Additionals []Record

+ Answers []Record

+ Authorities []Record

+ Header Header

+ Questions []Question

+ func DecodeMessage(packet []byte) (*Message, error)

+ func DecodeResponse(packet []byte, id uint16, question Question) (*Message, error)

+ func LookupDOHWireMessage(ctx context.Context, serverURL *url.URL, host string, answerType int) (*Message, error)

+ func LookupDoQMessage(ctx context.Context, cfg DoQConfig, name string, typ uint16) (*Message, error)

+ func LookupQUICMessage(ctx context.Context, cfg QUICConfig, name string, typ uint16) (*Message, error)

+ func LookupStreamMessage(ctx context.Context, cfg StreamConfig, name string, typ uint16) (*Message, error)

+ func LookupUDPMessage(ctx context.Context, serverAddr, host string, typ uint16) (*Message, bool, error)

+ func (m *Message) ValidateResponse(id uint16, question Question) error

+ type Name struct

+ func ParseDNSName(value string) (Name, error)

+ func ParseName(value string) (Name, error)

+ func (n Name) Equal(other Name) bool

+ func (n Name) String() string

+ func (n Name) Wire() ([]byte, error)

+ type QUICConfig = StreamConfig

+ type QUICDialFunc func(context.Context, net.PacketConn, *net.UDPAddr, *tls.Config, *quic.Config) (*quic.Conn, error)

+ type Question struct

+ Class uint16

+ Name Name

+ Type uint16

+ type Record struct

+ Class uint16

+ Owner Name

+ Params []SVCParam

+ Port uint16

+ Preference uint16

+ Priority uint16

+ RData []byte

+ SOAValues [5]uint32

+ TTL uint32

+ TTLPresent bool

+ TXT [][]byte

+ Target *Name

+ Target2 *Name

+ Type uint16

+ Weight uint16

+ func AuthorizeAddressAnswers(m *Message, question Question) ([]Record, error)

+ func AuthorizeAnswers(m *Message, question Question) ([]Record, error)

+ func QuerySystemHTTPS(ctx context.Context, policy SystemResolverPolicy, host string, typ uint16) ([]Record, error)

+ type ResolvedEndpoint struct

+ Addrs []net.IPAddr

+ Host string

+ Port string

type Resolver

+ func (r *Resolver) CacheIdentity() string

+ func (r *Resolver) Close() error

+ func (r *Resolver) DiscoverHTTPS(ctx context.Context, host string, defaultPort uint16, randomInt func(int) int) (HTTPSDiscovery, error)

+ func (r *Resolver) DiscoverSVCB(ctx context.Context, host string, defaultPort uint16, randomInt func(int) int) (HTTPSDiscovery, error)

+ func (r *Resolver) DiscoverService(ctx context.Context, host string, typ uint16, defaultPort uint16, ...) (HTTPSDiscovery, error)

+ func (r *Resolver) LookupHTTPSRecords(ctx context.Context, host string) ([]Record, error)

+ func (r *Resolver) LookupSVCBRecords(ctx context.Context, host string) ([]Record, error)

+ func (r *Resolver) Provenance() string

+ func (r *Resolver) SetOwnedRoundTripper(transport http.RoundTripper) error

+ func (r *Resolver) SetRoundTripper(transport http.RoundTripper) error

+ type SVCBRecord struct

+ ALPN [][]byte

+ ECH []byte

+ HasPort bool

+ IPv4Hints []net.IP

+ IPv6Hints []net.IP

+ Mandatory []uint16

+ NoDefaultALPN bool

+ Owner Name

+ Params []SVCParam

+ Port uint16

+ Priority uint16

+ TTL uint32

+ TTLPresent bool

+ Target Name

+ UnsupportedMandatory []uint16

+ func ParseSVCBRData(raw []byte) (SVCBRecord, error)

+ func ParseSVCBRRSet(records []Record) ([]SVCBRecord, error)

+ func SortSVCBRecords(records []SVCBRecord, randomInt func(int) int) []SVCBRecord

+ func (r SVCBRecord) AdvertisesALPN(protocol string) bool

+ func (r SVCBRecord) IsAliasMode() bool

+ func (r SVCBRecord) IsUsable() bool

+ type SVCParam struct

+ Key uint16

+ Value []byte

+ type Security string

+ const SecurityPlaintext

+ const SecurityUnverifiedEncrypt

+ const SecurityVerifiedEncrypted

+ type ServiceCandidate struct

+ ALPN [][]byte

+ Addresses []net.IPAddr

+ ECH []byte

+ Hints []net.IPAddr

+ NoDefaultALPN bool

+ OriginName Name

+ Port uint16

+ Priority uint16

+ TTL uint32

+ TTLPresent bool

+ TargetName Name

+ type ServiceDiscoveryOptions struct

+ AddressLookup AddressLookup

+ Authenticated bool

+ DefaultPort uint16

+ MaxAliasDepth int

+ RandomInt func(int) int

+ type StreamClient struct

+ func NewStreamClient(ctx context.Context, cfg StreamConfig) (*StreamClient, error)

+ func (c *StreamClient) Close() error

+ func (c *StreamClient) Query(ctx context.Context, name string, typ uint16) (*Message, error)

+ func (c *StreamClient) QueryMany(ctx context.Context, queries []Question) ([]*Message, error)

+ type StreamConfig struct

+ Bootstrap BootstrapFunc

+ CACerts []*x509.Certificate

+ ClientCert *tls.Certificate

+ DialContext DialContextFunc

+ Endpoint *Endpoint

+ Insecure bool

+ QUICDial QUICDialFunc

+ TLSConfig *tls.Config

+ TLSMax uint16

+ TLSMin uint16

+ type SystemResolverPolicy struct

+ Attempts int

+ Nameservers []string

+ ResolvConfPath string

+ Rotate bool

+ Timeout time.Duration

+ UseSystemdResolved bool

+ func LoadSystemResolverPolicy(path string) (SystemResolverPolicy, error)

+ func ParseResolvConf(data string) SystemResolverPolicy

+ type Transport string

+ const TransportHTTPS

+ const TransportQUIC

+ const TransportTCP

+ const TransportTLS

+ const TransportUDP

v0.23.4

May 16, 2026

v0.23.3

May 15, 2026

v0.23.2

May 12, 2026

v0.23.1

May 11, 2026

v0.23.0

May 9, 2026

Changes in this version

+ type Config struct

+ Server *url.URL

+ type DNSRecord struct

+ IP net.IP

+ TTL int

+ func LookupDOHType(ctx context.Context, serverURL *url.URL, host, dnsType string, answerType int) ([]DNSRecord, error)

+ type Endpoint struct

+ Addrs []net.IPAddr

+ Host string

+ Port string

+ type Resolver struct

+ func New(cfg Config) *Resolver

+ func (r *Resolver) DialContext(ctx context.Context, network, address string) (net.Conn, error)

+ func (r *Resolver) LookupIPAddr(ctx context.Context, host string) ([]net.IPAddr, error)

+ func (r *Resolver) NetResolver() *net.Resolver

+ func (r *Resolver) ResolveAddress(ctx context.Context, network, address string) (Endpoint, error)