github.com/elfadel/cilium@v1.6.12/pkg/fqdn/config.go (about)

     1  // Copyright 2018 Authors of Cilium
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package fqdn
    16  
    17  import (
    18  	"context"
    19  	"net"
    20  	"sync"
    21  	"time"
    22  
    23  	"github.com/cilium/cilium/pkg/policy/api"
    24  	"github.com/miekg/dns"
    25  )
    26  
    27  // Config is a simple configuration structure to set how pkg/fqdn subcomponents
    28  // behave.
    29  // DNSPoller relies on LookupDNSNames to control how DNS lookups are done, and
    30  // UpdateSelectors to control how generated policy rules are emitted.
    31  type Config struct {
    32  	// MinTTL is the time used by the poller to cache information.
    33  	// When set to 0, 2*DNSPollerInterval is used.
    34  	MinTTL int
    35  
    36  	// OverLimit is the number of max entries that a host can have in the DNS cache.
    37  	OverLimit int
    38  
    39  	// Cache is where the poller stores DNS data used to generate rules.
    40  	// When set to nil, it uses fqdn.DefaultDNSCache, a global cache instance.
    41  	Cache *DNSCache
    42  
    43  	// DNSConfig includes the Resolver IPs, port, timeout and retry count. It is
    44  	// expected to be  generated from /etc/resolv.conf.
    45  	DNSConfig *dns.ClientConfig
    46  
    47  	// LookupDNSNames is a callback to run the provided DNS lookups.
    48  	// When set to nil, fqdn.DNSLookupDefaultResolver is used.
    49  	LookupDNSNames func(dnsNames []string) (DNSIPs map[string]*DNSIPRecords, errorDNSNames map[string]error)
    50  
    51  	// UpdateSelectors is a callback to update the mapping of FQDNSelector to
    52  	// sets of IPs.
    53  	UpdateSelectors func(ctx context.Context, selectorsWithIPs map[api.FQDNSelector][]net.IP, selectorsWithoutIPs []api.FQDNSelector) (*sync.WaitGroup, error)
    54  
    55  	// PollerResponseNotify is used when the poller receives DNS data in response
    56  	// to a successful poll.
    57  	// Note: This function doesn't do much, as the poller is still wired to
    58  	// NameManager directly right now.
    59  	PollerResponseNotify func(lookupTime time.Time, qname string, response *DNSIPRecords)
    60  }