dnscache

package

v1.8.2-rc1 Latest Latest Go to latest Published: Oct 12, 2026 License: MIT Imports: 10 Imported by: 0

Details

Valid go.mod file
Redistributable license
Tagged version
Stable version
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Repository

github.com/crowdsecurity/crowdsec

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Documentation ¶

Overview ¶

Package dnscache provides process-wide cached DNS lookups: PTR records, forward (A/AAAA) records, and forward-confirmed reverse DNS (FCrDNS) composed from the two. Results — including failures — are cached in a shared LRU, and concurrent lookups for the same key coalesce via singleflight, so a given DNS fact costs at most one query per TTL.

Consumers: the parser's reverse_dns enricher (PTR only) and the MatchKnownBot (FCrDNS) and LookupHost (forward) expr helpers.

Index ¶

func Configure(posTTL time.Duration, negTTL time.Duration, size int)
func ForwardConfirmedNames(addr netip.Addr) []string
func ForwardIPs(host string) []netip.Addr
func ForwardLookup(host string) ([]netip.Addr, error)
func PTRRecords(addr netip.Addr) []string
func Purge()
func SetResolver(r Resolver)
type Resolver

Constants ¶

This section is empty.

Variables ¶

This section is empty.

Functions ¶

func Configure ¶

func Configure(posTTL time.Duration, negTTL time.Duration, size int)

func ForwardConfirmedNames ¶

func ForwardConfirmedNames(addr netip.Addr) []string

func ForwardIPs ¶

func ForwardIPs(host string) []netip.Addr

func ForwardLookup ¶

func ForwardLookup(host string) ([]netip.Addr, error)

ForwardLookup is ForwardIPs with the error of a failed lookup, which is cached with the empty result for the negative TTL.

func PTRRecords ¶

func PTRRecords(addr netip.Addr) []string

func Purge ¶

func Purge()

func SetResolver ¶

func SetResolver(r Resolver)

Types ¶

type Resolver ¶

type Resolver interface {
	LookupAddr(ctx context.Context, addr string) ([]string, error)
	LookupIPAddr(ctx context.Context, host string) ([]net.IPAddr, error)
}

Resolver is satisfied by *net.Resolver; swapped for a fake in tests.

Source Files ¶

View all Source files

dnscache.go

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