From 01de8a29bce14cdfd7d3fcf3c0ebe3914be6edd0 Mon Sep 17 00:00:00 2001 From: m5r Date: Sat, 29 Oct 2022 10:10:54 +0200 Subject: [PATCH] handle NS --- xip/xip.go | 110 +++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 82 insertions(+), 28 deletions(-) diff --git a/xip/xip.go b/xip/xip.go index f5d20fd..42d16d1 100644 --- a/xip/xip.go +++ b/xip/xip.go @@ -19,38 +19,87 @@ type Xip struct { } var ( - flyRegion = os.Getenv("FLY_REGION") - dottedIpV4Regex = regexp.MustCompile(`(?:^|(?:[\w\d])+\.)(((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\.?\b){4})($|[.-])`) - dashedIpV4Regex = regexp.MustCompile(`(?:^|(?:[\w\d])+\.)(((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\-?\b){4})($|[.-])`) + flyRegion = os.Getenv("FLY_REGION") + dottedIpV4Regex = regexp.MustCompile(`(?:^|(?:[\w\d])+\.)(((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\.?\b){4})($|[.-])`) + dashedIpV4Regex = regexp.MustCompile(`(?:^|(?:[\w\d])+\.)(((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\-?\b){4})($|[.-])`) + hardcodedDomains = map[string]net.IP{ + "ns.local-ip.sh.": net.IPv4(137, 66, 38, 214), + "ns1.local-ip.sh.": net.IPv4(137, 66, 38, 214), + "ns2.local-ip.sh.": net.IPv4(137, 66, 38, 214), + } ) +func (xip *Xip) fqdnToA(fqdn string) *dns.A { + var ipV4Address net.IP + + if hardcodedDomains[strings.ToLower(fqdn)] != nil { + ipV4Address = hardcodedDomains[strings.ToLower(fqdn)] + } else { + for _, ipV4RE := range []*regexp.Regexp{dashedIpV4Regex, dottedIpV4Regex} { + if ipV4RE.MatchString(fqdn) { + match := ipV4RE.FindStringSubmatch(fqdn)[1] + match = strings.ReplaceAll(match, "-", ".") + ipV4Address = net.ParseIP(match).To4() + break + } + } + } + + if ipV4Address == nil { + return nil + } + + return &dns.A{ + Hdr: dns.RR_Header{ + // Ttl: uint32((time.Hour * 24 * 7).Seconds()), + Ttl: uint32((time.Second * 10).Seconds()), + Name: fqdn, + Rrtype: dns.TypeA, + Class: dns.ClassINET, + }, + A: ipV4Address, + } +} + func (xip *Xip) handleA(question dns.Question, message *dns.Msg) { fqdn := question.Name + record := xip.fqdnToA(fqdn) - for _, ipV4RE := range []*regexp.Regexp{dashedIpV4Regex, dottedIpV4Regex} { - if ipV4RE.MatchString(fqdn) { - match := ipV4RE.FindStringSubmatch(fqdn)[1] - match = strings.ReplaceAll(match, "-", ".") - ipV4Address := net.ParseIP(match).To4() - if ipV4Address == nil { - message.Rcode = dns.RcodeNameError - message.Ns = append(message.Ns, xip.SOARecord(question)) - return - } + if record == nil { + message.Rcode = dns.RcodeNameError + message.Ns = append(message.Ns, xip.SOARecord(question)) + return + } - record := &dns.A{ - Hdr: dns.RR_Header{ - // Ttl: uint32((time.Hour * 24 * 7).Seconds()), - Ttl: uint32((time.Second * 10).Seconds()), - Name: fqdn, - Rrtype: dns.TypeA, - Class: dns.ClassINET, - }, - A: ipV4Address, - } - log.Printf("(%s) %s => %s\n", flyRegion, fqdn, ipV4Address) - message.Answer = append(message.Answer, record) - } + log.Printf("(%s) %s => %s\n", flyRegion, fqdn, record.A) + message.Answer = append(message.Answer, record) +} + +func (xip *Xip) handleNS(question dns.Question, message *dns.Msg) { + fqdn := question.Name + nameServers := []*dns.NS{} + additionals := []*dns.A{} + for _, ns := range xip.NameServers { + nameServers = append(nameServers, &dns.NS{ + Hdr: dns.RR_Header{ + // Ttl: uint32((time.Hour * 24 * 7).Seconds()), + Ttl: uint32((time.Second * 10).Seconds()), + Name: fqdn, + Rrtype: dns.TypeNS, + Class: dns.ClassINET, + }, + Ns: ns.Ns, + }) + + additionals = append(additionals, xip.fqdnToA(ns.Ns)) + } + + for _, record := range nameServers { + message.Answer = append(message.Answer, record) + } + + for _, record := range additionals { + message.Extra = append(message.Extra, record) } } @@ -64,8 +113,8 @@ func (xip *Xip) SOARecord(question dns.Question) *dns.SOA { Ttl: uint32((time.Second * 10).Seconds()), Rdlength: 0, } - soa.Ns = "ns.local-ip.dev." - soa.Mbox = "admin.local-ip.dev." + soa.Ns = "ns.local-ip.sh." + soa.Mbox = "admin.local-ip.sh." soa.Serial = 2022102800 // soa.Refresh = uint32((time.Minute * 15).Seconds()) soa.Refresh = uint32((time.Second * 10).Seconds()) @@ -81,9 +130,14 @@ func (xip *Xip) SOARecord(question dns.Question) *dns.SOA { func (xip *Xip) handleQuery(message *dns.Msg) { for _, question := range message.Question { + log.Printf("name: %s\n", question.Name) + log.Printf("class: %d\n", question.Qclass) + log.Printf("type: %d\n", question.Qtype) switch question.Qtype { case dns.TypeA: xip.handleA(question, message) + case dns.TypeNS: + xip.handleNS(question, message) } } }