CalvinBackup/ctrld
1
0
Fork 0
mirror of https://github.com/Control-D-Inc/ctrld.git synced 2026-02-03 22:18:39 +00:00
Code Issues Packages Projects Releases Wiki Activity

all: rework bootstrap IP discovering

Browse Source 
At startup, ctrld gathers bootstrap IP information and use this
bootstrap IP for connecting to upstream. However, in case the network
stack changed, for example, dues to VPN connection, ctrld will still use
this old (maybe invalid) bootstrap IP for the current network stack.

This commit rework the discovering process, and re-initializing the
bootstrap IP if connecting to upstream failed.
This commit is contained in:
Cuong Manh Le
2023-03-01 11:14:10 +07:00
committed by Cuong Manh Le
parent 930a5ad439
commit 8b08cc8a6e
7 changed files with 95 additions and 53 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
cmd/ctrld/dns_proxy.go
View File

@@ -4,6 +4,7 @@ import (
"context"
"crypto/rand"
"encoding/hex"
"errors"
"fmt"
"net"
"runtime"
@@ -182,6 +183,15 @@ func (p *prog) proxy(ctx context.Context, upstreams []string, failoverRcodes []i
resolveCtx = timeoutCtx
}
answer, err := dnsResolver.Resolve(resolveCtx, msg)
if errors.Is(err, ctrld.ErrUpstreamFailed) {
ctrldnet.Reset()
if err := upstreamConfig.SetupBootstrapIP(); err != nil {
mainLog.Error().Err(err).Msg("could not re-initialize bootstrap IP")
} else {
mainLog.Debug().Msg("re-initialize bootstrap IP done")
}
return nil
}
if err != nil {
ctrld.Log(ctx, mainLog.Error().Err(err), "failed to resolve query")
return nil

44
cmd/ctrld/prog.go
View File

@@ -11,11 +11,9 @@ import (
"syscall"
"github.com/kardianos/service"
"github.com/miekg/dns"
"github.com/Control-D-Inc/ctrld"
"github.com/Control-D-Inc/ctrld/internal/dnscache"
ctrldnet "github.com/Control-D-Inc/ctrld/internal/net"
)
var logf = func(format string, args ...any) {
@@ -37,7 +35,6 @@ type prog struct {
func (p *prog) Start(s service.Service) error {
p.cfg = &cfg
go p.run()
mainLog.Info().Msg("Service started")
return nil
}
@@ -67,45 +64,10 @@ func (p *prog) run() {
for n := range p.cfg.Upstream {
uc := p.cfg.Upstream[n]
uc.Init()
if uc.BootstrapIP == "" {
// resolve it manually and set the bootstrap ip
c := new(dns.Client)
for _, dnsType := range []uint16{dns.TypeAAAA, dns.TypeA} {
if !ctrldnet.SupportsIPv6() && dnsType == dns.TypeAAAA {
continue
}
m := new(dns.Msg)
m.SetQuestion(uc.Domain+".", dnsType)
m.RecursionDesired = true
r, _, err := c.Exchange(m, net.JoinHostPort(bootstrapDNS, "53"))
if err != nil {
mainLog.Error().Err(err).Msgf("could not resolve domain %s for upstream.%s", uc.Domain, n)
continue
}
if r.Rcode != dns.RcodeSuccess {
mainLog.Error().Msgf("could not resolve domain return code: %d, upstream.%s", r.Rcode, n)
continue
}
if len(r.Answer) == 0 {
continue
}
for _, a := range r.Answer {
switch ar := a.(type) {
case *dns.A:
uc.BootstrapIP = ar.A.String()
case *dns.AAAA:
uc.BootstrapIP = ar.AAAA.String()
default:
continue
}
mainLog.Info().Str("bootstrap_ip", uc.BootstrapIP).Msgf("Setting bootstrap IP for upstream.%s", n)
// Stop if we reached here, because we got the bootstrap IP from r.Answer.
break
}
// If we reached here, uc.BootstrapIP was set, nothing to do anymore.
break
}
if err := uc.SetupBootstrapIP(); err != nil {
mainLog.Fatal().Err(err).Msgf("failed to setup bootstrap IP for upstream.%s", n)
}
mainLog.Info().Str("bootstrap_ip", uc.BootstrapIP).Msgf("Setting bootstrap IP for upstream.%s", n)
uc.SetupTransport()
}