lordwelch/router7
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

dns: return NXDOMAIN for DHCP leases once they expire

Browse Source
This commit is contained in:
Michael Stapelberg 2019-09-07 19:27:12 +02:00
parent fa82132962
commit 70edcab16b
2 changed files with 29 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
internal/dns/dns.go
View File

@ -448,7 +448,12 @@ func (s *Server) resolveSubname(hostname string, q dns.Question) (dns.RR, error)
if lower := strings.ToLower(q.Name); lower == hostname+"." ||
lower == hostname+"."+s.domain+"." {
host, _ := s.hostByName(hostname)
host, ok := s.hostByName(hostname)
if !ok {
// The corresponding DHCP lease might have expired, but this
// handler is still installed on the mux.
return nil, nil // NXDOMAIN
}
if q.Qtype == dns.TypeA {
return dns.NewRR(q.Name + " 3600 IN A " + host)
}
@ -482,7 +487,7 @@ func (s *Server) subnameHandler(hostname string) func(w dns.ResponseWriter, r *d
w.WriteMsg(m)
return
}
log.Fatal(err)
log.Fatalf("question %#v: %v", r.Question[0], err)
}
if rr != nil {
m := new(dns.Msg)

22
internal/dns/dns_test.go
View File

@ -187,6 +187,11 @@ func TestDHCP(t *testing.T) {
Addr: net.IP{192, 168, 42, 150},
Expiry: expired,
},
{
Hostname: "aged",
Addr: net.IP{192, 168, 42, 42},
Expiry: time.Now().Add(1 * time.Minute),
},
})
t.Run("testtarget.lan. (expired)", func(t *testing.T) {
@ -203,6 +208,23 @@ func TestDHCP(t *testing.T) {
t.Fatalf("unexpected rcode: got %v, want %v", got, want)
}
})
s.SetLeases([]dhcp4d.Lease{
{
Hostname: "aged",
Addr: net.IP{192, 168, 42, 42},
Expiry: expired,
},
})
t.Run("aged.lan. (expired)", func(t *testing.T) {
m := new(dns.Msg)
m.SetQuestion("aged.lan.", dns.TypeA)
s.Mux.ServeDNS(r, m)
if got, want := r.response.Rcode, dns.RcodeNameError; got != want {
t.Fatalf("unexpected rcode: got %v, want %v", got, want)
}
})
}
func TestHostname(t *testing.T) {