diff options
Diffstat (limited to 'src/net/lookup.go')
| -rw-r--r-- | src/net/lookup.go | 226 |
1 files changed, 0 insertions, 226 deletions
diff --git a/src/net/lookup.go b/src/net/lookup.go index 7f3d20126c9..6fa90f354d4 100644 --- a/src/net/lookup.go +++ b/src/net/lookup.go @@ -10,8 +10,6 @@ import ( "internal/singleflight" "net/netip" "sync" - - "golang.org/x/net/dns/dnsmessage" ) // protocols contains minimal mappings between internet protocol @@ -667,227 +665,3 @@ func (r *Resolver) LookupAddr(ctx context.Context, addr string) ([]string, error // method receives DNS records which contain invalid DNS names. This may be returned alongside // results which have had the malformed records filtered out. var errMalformedDNSRecordsDetail = "DNS response contained records which contain invalid names" - -// dial makes a new connection to the provided server (which must be -// an IP address) with the provided network type, using either r.Dial -// (if both r and r.Dial are non-nil) or else Dialer.DialContext. -func (r *Resolver) dial(ctx context.Context, network, server string) (Conn, error) { - // Calling Dial here is scary -- we have to be sure not to - // dial a name that will require a DNS lookup, or Dial will - // call back here to translate it. The DNS config parser has - // already checked that all the cfg.servers are IP - // addresses, which Dial will use without a DNS lookup. - var c Conn - var err error - if r != nil && r.Dial != nil { - c, err = r.Dial(ctx, network, server) - } else { - var d Dialer - c, err = d.DialContext(ctx, network, server) - } - if err != nil { - return nil, mapErr(err) - } - return c, nil -} - -// goLookupSRV returns the SRV records for a target name, built either -// from its component service ("sip"), protocol ("tcp"), and name -// ("example.com."), or from name directly (if service and proto are -// both empty). -// -// In either case, the returned target name ("_sip._tcp.example.com.") -// is also returned on success. -// -// The records are sorted by weight. -func (r *Resolver) goLookupSRV(ctx context.Context, service, proto, name string) (target string, srvs []*SRV, err error) { - if service == "" && proto == "" { - target = name - } else { - target = "_" + service + "._" + proto + "." + name - } - p, server, err := r.lookup(ctx, target, dnsmessage.TypeSRV) - if err != nil { - return "", nil, err - } - var cname dnsmessage.Name - for { - h, err := p.AnswerHeader() - if err == dnsmessage.ErrSectionDone { - break - } - if err != nil { - return "", nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - if h.Type != dnsmessage.TypeSRV { - if err := p.SkipAnswer(); err != nil { - return "", nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - continue - } - if cname.Length == 0 && h.Name.Length != 0 { - cname = h.Name - } - srv, err := p.SRVResource() - if err != nil { - return "", nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - srvs = append(srvs, &SRV{Target: srv.Target.String(), Port: srv.Port, Priority: srv.Priority, Weight: srv.Weight}) - } - byPriorityWeight(srvs).sort() - return cname.String(), srvs, nil -} - -// goLookupMX returns the MX records for name. -func (r *Resolver) goLookupMX(ctx context.Context, name string) ([]*MX, error) { - p, server, err := r.lookup(ctx, name, dnsmessage.TypeMX) - if err != nil { - return nil, err - } - var mxs []*MX - for { - h, err := p.AnswerHeader() - if err == dnsmessage.ErrSectionDone { - break - } - if err != nil { - return nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - if h.Type != dnsmessage.TypeMX { - if err := p.SkipAnswer(); err != nil { - return nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - continue - } - mx, err := p.MXResource() - if err != nil { - return nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - mxs = append(mxs, &MX{Host: mx.MX.String(), Pref: mx.Pref}) - - } - byPref(mxs).sort() - return mxs, nil -} - -// goLookupNS returns the NS records for name. -func (r *Resolver) goLookupNS(ctx context.Context, name string) ([]*NS, error) { - p, server, err := r.lookup(ctx, name, dnsmessage.TypeNS) - if err != nil { - return nil, err - } - var nss []*NS - for { - h, err := p.AnswerHeader() - if err == dnsmessage.ErrSectionDone { - break - } - if err != nil { - return nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - if h.Type != dnsmessage.TypeNS { - if err := p.SkipAnswer(); err != nil { - return nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - continue - } - ns, err := p.NSResource() - if err != nil { - return nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - nss = append(nss, &NS{Host: ns.NS.String()}) - } - return nss, nil -} - -// goLookupTXT returns the TXT records from name. -func (r *Resolver) goLookupTXT(ctx context.Context, name string) ([]string, error) { - p, server, err := r.lookup(ctx, name, dnsmessage.TypeTXT) - if err != nil { - return nil, err - } - var txts []string - for { - h, err := p.AnswerHeader() - if err == dnsmessage.ErrSectionDone { - break - } - if err != nil { - return nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - if h.Type != dnsmessage.TypeTXT { - if err := p.SkipAnswer(); err != nil { - return nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - continue - } - txt, err := p.TXTResource() - if err != nil { - return nil, &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } - } - // Multiple strings in one TXT record need to be - // concatenated without separator to be consistent - // with previous Go resolver. - n := 0 - for _, s := range txt.TXT { - n += len(s) - } - txtJoin := make([]byte, 0, n) - for _, s := range txt.TXT { - txtJoin = append(txtJoin, s...) - } - if len(txts) == 0 { - txts = make([]string, 0, 1) - } - txts = append(txts, string(txtJoin)) - } - return txts, nil -} |