mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-11-01 06:50:00 +00:00
857 lines
26 KiB
Go
857 lines
26 KiB
Go
package dns
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import (
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"encoding/binary"
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"encoding/hex"
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"errors"
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"fmt"
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"net"
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"strconv"
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)
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// EDNS0 Option codes.
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const (
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EDNS0LLQ = 0x1 // long lived queries: http://tools.ietf.org/html/draft-sekar-dns-llq-01
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EDNS0UL = 0x2 // update lease draft: http://files.dns-sd.org/draft-sekar-dns-ul.txt
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EDNS0NSID = 0x3 // nsid (See RFC 5001)
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EDNS0ESU = 0x4 // ENUM Source-URI draft: https://datatracker.ietf.org/doc/html/draft-kaplan-enum-source-uri-00
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EDNS0DAU = 0x5 // DNSSEC Algorithm Understood
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EDNS0DHU = 0x6 // DS Hash Understood
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EDNS0N3U = 0x7 // NSEC3 Hash Understood
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EDNS0SUBNET = 0x8 // client-subnet (See RFC 7871)
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EDNS0EXPIRE = 0x9 // EDNS0 expire
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EDNS0COOKIE = 0xa // EDNS0 Cookie
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EDNS0TCPKEEPALIVE = 0xb // EDNS0 tcp keep alive (See RFC 7828)
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EDNS0PADDING = 0xc // EDNS0 padding (See RFC 7830)
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EDNS0EDE = 0xf // EDNS0 extended DNS errors (See RFC 8914)
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EDNS0LOCALSTART = 0xFDE9 // Beginning of range reserved for local/experimental use (See RFC 6891)
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EDNS0LOCALEND = 0xFFFE // End of range reserved for local/experimental use (See RFC 6891)
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_DO = 1 << 15 // DNSSEC OK
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)
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// makeDataOpt is used to unpack the EDNS0 option(s) from a message.
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func makeDataOpt(code uint16) EDNS0 {
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// All the EDNS0.* constants above need to be in this switch.
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switch code {
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case EDNS0LLQ:
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return new(EDNS0_LLQ)
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case EDNS0UL:
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return new(EDNS0_UL)
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case EDNS0NSID:
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return new(EDNS0_NSID)
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case EDNS0DAU:
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return new(EDNS0_DAU)
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case EDNS0DHU:
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return new(EDNS0_DHU)
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case EDNS0N3U:
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return new(EDNS0_N3U)
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case EDNS0SUBNET:
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return new(EDNS0_SUBNET)
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case EDNS0EXPIRE:
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return new(EDNS0_EXPIRE)
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case EDNS0COOKIE:
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return new(EDNS0_COOKIE)
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case EDNS0TCPKEEPALIVE:
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return new(EDNS0_TCP_KEEPALIVE)
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case EDNS0PADDING:
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return new(EDNS0_PADDING)
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case EDNS0EDE:
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return new(EDNS0_EDE)
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case EDNS0ESU:
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return &EDNS0_ESU{Code: EDNS0ESU}
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default:
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e := new(EDNS0_LOCAL)
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e.Code = code
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return e
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}
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}
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// OPT is the EDNS0 RR appended to messages to convey extra (meta) information.
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// See RFC 6891.
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type OPT struct {
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Hdr RR_Header
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Option []EDNS0 `dns:"opt"`
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}
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func (rr *OPT) String() string {
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s := "\n;; OPT PSEUDOSECTION:\n; EDNS: version " + strconv.Itoa(int(rr.Version())) + "; "
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if rr.Do() {
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s += "flags: do; "
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} else {
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s += "flags:; "
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}
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if rr.Hdr.Ttl&0x7FFF != 0 {
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s += fmt.Sprintf("MBZ: 0x%04x, ", rr.Hdr.Ttl&0x7FFF)
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}
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s += "udp: " + strconv.Itoa(int(rr.UDPSize()))
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for _, o := range rr.Option {
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switch o.(type) {
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case *EDNS0_NSID:
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s += "\n; NSID: " + o.String()
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h, e := o.pack()
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var r string
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if e == nil {
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for _, c := range h {
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r += "(" + string(c) + ")"
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}
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s += " " + r
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}
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case *EDNS0_SUBNET:
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s += "\n; SUBNET: " + o.String()
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case *EDNS0_COOKIE:
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s += "\n; COOKIE: " + o.String()
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case *EDNS0_EXPIRE:
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s += "\n; EXPIRE: " + o.String()
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case *EDNS0_TCP_KEEPALIVE:
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s += "\n; KEEPALIVE: " + o.String()
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case *EDNS0_UL:
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s += "\n; UPDATE LEASE: " + o.String()
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case *EDNS0_LLQ:
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s += "\n; LONG LIVED QUERIES: " + o.String()
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case *EDNS0_DAU:
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s += "\n; DNSSEC ALGORITHM UNDERSTOOD: " + o.String()
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case *EDNS0_DHU:
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s += "\n; DS HASH UNDERSTOOD: " + o.String()
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case *EDNS0_N3U:
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s += "\n; NSEC3 HASH UNDERSTOOD: " + o.String()
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case *EDNS0_LOCAL:
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s += "\n; LOCAL OPT: " + o.String()
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case *EDNS0_PADDING:
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s += "\n; PADDING: " + o.String()
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case *EDNS0_EDE:
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s += "\n; EDE: " + o.String()
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case *EDNS0_ESU:
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s += "\n; ESU: " + o.String()
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}
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}
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return s
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}
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func (rr *OPT) len(off int, compression map[string]struct{}) int {
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l := rr.Hdr.len(off, compression)
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for _, o := range rr.Option {
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l += 4 // Account for 2-byte option code and 2-byte option length.
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lo, _ := o.pack()
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l += len(lo)
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}
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return l
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}
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func (*OPT) parse(c *zlexer, origin string) *ParseError {
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return &ParseError{err: "OPT records do not have a presentation format"}
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}
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func (rr *OPT) isDuplicate(r2 RR) bool { return false }
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// return the old value -> delete SetVersion?
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// Version returns the EDNS version used. Only zero is defined.
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func (rr *OPT) Version() uint8 {
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return uint8(rr.Hdr.Ttl & 0x00FF0000 >> 16)
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}
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// SetVersion sets the version of EDNS. This is usually zero.
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func (rr *OPT) SetVersion(v uint8) {
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rr.Hdr.Ttl = rr.Hdr.Ttl&0xFF00FFFF | uint32(v)<<16
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}
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// ExtendedRcode returns the EDNS extended RCODE field (the upper 8 bits of the TTL).
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func (rr *OPT) ExtendedRcode() int {
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return int(rr.Hdr.Ttl&0xFF000000>>24) << 4
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}
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// SetExtendedRcode sets the EDNS extended RCODE field.
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//
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// If the RCODE is not an extended RCODE, will reset the extended RCODE field to 0.
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func (rr *OPT) SetExtendedRcode(v uint16) {
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rr.Hdr.Ttl = rr.Hdr.Ttl&0x00FFFFFF | uint32(v>>4)<<24
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}
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// UDPSize returns the UDP buffer size.
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func (rr *OPT) UDPSize() uint16 {
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return rr.Hdr.Class
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}
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// SetUDPSize sets the UDP buffer size.
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func (rr *OPT) SetUDPSize(size uint16) {
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rr.Hdr.Class = size
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}
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// Do returns the value of the DO (DNSSEC OK) bit.
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func (rr *OPT) Do() bool {
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return rr.Hdr.Ttl&_DO == _DO
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}
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// SetDo sets the DO (DNSSEC OK) bit.
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// If we pass an argument, set the DO bit to that value.
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// It is possible to pass 2 or more arguments, but they will be ignored.
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func (rr *OPT) SetDo(do ...bool) {
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if len(do) == 1 {
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if do[0] {
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rr.Hdr.Ttl |= _DO
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} else {
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rr.Hdr.Ttl &^= _DO
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}
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} else {
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rr.Hdr.Ttl |= _DO
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}
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}
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// Z returns the Z part of the OPT RR as a uint16 with only the 15 least significant bits used.
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func (rr *OPT) Z() uint16 {
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return uint16(rr.Hdr.Ttl & 0x7FFF)
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}
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// SetZ sets the Z part of the OPT RR, note only the 15 least significant bits of z are used.
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func (rr *OPT) SetZ(z uint16) {
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rr.Hdr.Ttl = rr.Hdr.Ttl&^0x7FFF | uint32(z&0x7FFF)
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}
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// EDNS0 defines an EDNS0 Option. An OPT RR can have multiple options appended to it.
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type EDNS0 interface {
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// Option returns the option code for the option.
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Option() uint16
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// pack returns the bytes of the option data.
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pack() ([]byte, error)
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// unpack sets the data as found in the buffer. Is also sets
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// the length of the slice as the length of the option data.
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unpack([]byte) error
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// String returns the string representation of the option.
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String() string
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// copy returns a deep-copy of the option.
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copy() EDNS0
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}
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// EDNS0_NSID option is used to retrieve a nameserver
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// identifier. When sending a request Nsid must be set to the empty string
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// The identifier is an opaque string encoded as hex.
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// Basic use pattern for creating an nsid option:
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//
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// o := new(dns.OPT)
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// o.Hdr.Name = "."
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// o.Hdr.Rrtype = dns.TypeOPT
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// e := new(dns.EDNS0_NSID)
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// e.Code = dns.EDNS0NSID
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// e.Nsid = "AA"
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// o.Option = append(o.Option, e)
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type EDNS0_NSID struct {
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Code uint16 // Always EDNS0NSID
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Nsid string // This string needs to be hex encoded
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}
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func (e *EDNS0_NSID) pack() ([]byte, error) {
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h, err := hex.DecodeString(e.Nsid)
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if err != nil {
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return nil, err
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}
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return h, nil
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}
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// Option implements the EDNS0 interface.
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func (e *EDNS0_NSID) Option() uint16 { return EDNS0NSID } // Option returns the option code.
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func (e *EDNS0_NSID) unpack(b []byte) error { e.Nsid = hex.EncodeToString(b); return nil }
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func (e *EDNS0_NSID) String() string { return e.Nsid }
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func (e *EDNS0_NSID) copy() EDNS0 { return &EDNS0_NSID{e.Code, e.Nsid} }
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// EDNS0_SUBNET is the subnet option that is used to give the remote nameserver
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// an idea of where the client lives. See RFC 7871. It can then give back a different
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// answer depending on the location or network topology.
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// Basic use pattern for creating an subnet option:
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//
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// o := new(dns.OPT)
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// o.Hdr.Name = "."
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// o.Hdr.Rrtype = dns.TypeOPT
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// e := new(dns.EDNS0_SUBNET)
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// e.Code = dns.EDNS0SUBNET // by default this is filled in through unpacking OPT packets (unpackDataOpt)
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// e.Family = 1 // 1 for IPv4 source address, 2 for IPv6
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// e.SourceNetmask = 32 // 32 for IPV4, 128 for IPv6
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// e.SourceScope = 0
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// e.Address = net.ParseIP("127.0.0.1").To4() // for IPv4
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// // e.Address = net.ParseIP("2001:7b8:32a::2") // for IPV6
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// o.Option = append(o.Option, e)
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//
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// This code will parse all the available bits when unpacking (up to optlen).
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// When packing it will apply SourceNetmask. If you need more advanced logic,
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// patches welcome and good luck.
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type EDNS0_SUBNET struct {
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Code uint16 // Always EDNS0SUBNET
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Family uint16 // 1 for IP, 2 for IP6
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SourceNetmask uint8
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SourceScope uint8
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Address net.IP
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}
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// Option implements the EDNS0 interface.
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func (e *EDNS0_SUBNET) Option() uint16 { return EDNS0SUBNET }
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func (e *EDNS0_SUBNET) pack() ([]byte, error) {
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b := make([]byte, 4)
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binary.BigEndian.PutUint16(b[0:], e.Family)
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b[2] = e.SourceNetmask
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b[3] = e.SourceScope
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switch e.Family {
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case 0:
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// "dig" sets AddressFamily to 0 if SourceNetmask is also 0
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// We might don't need to complain either
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if e.SourceNetmask != 0 {
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return nil, errors.New("dns: bad address family")
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}
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case 1:
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if e.SourceNetmask > net.IPv4len*8 {
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return nil, errors.New("dns: bad netmask")
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}
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if len(e.Address.To4()) != net.IPv4len {
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return nil, errors.New("dns: bad address")
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}
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ip := e.Address.To4().Mask(net.CIDRMask(int(e.SourceNetmask), net.IPv4len*8))
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needLength := (e.SourceNetmask + 8 - 1) / 8 // division rounding up
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b = append(b, ip[:needLength]...)
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case 2:
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if e.SourceNetmask > net.IPv6len*8 {
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return nil, errors.New("dns: bad netmask")
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}
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if len(e.Address) != net.IPv6len {
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return nil, errors.New("dns: bad address")
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}
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ip := e.Address.Mask(net.CIDRMask(int(e.SourceNetmask), net.IPv6len*8))
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needLength := (e.SourceNetmask + 8 - 1) / 8 // division rounding up
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b = append(b, ip[:needLength]...)
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default:
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return nil, errors.New("dns: bad address family")
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}
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return b, nil
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}
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func (e *EDNS0_SUBNET) unpack(b []byte) error {
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if len(b) < 4 {
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return ErrBuf
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}
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e.Family = binary.BigEndian.Uint16(b)
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e.SourceNetmask = b[2]
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e.SourceScope = b[3]
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switch e.Family {
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case 0:
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// "dig" sets AddressFamily to 0 if SourceNetmask is also 0
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// It's okay to accept such a packet
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if e.SourceNetmask != 0 {
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return errors.New("dns: bad address family")
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}
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e.Address = net.IPv4(0, 0, 0, 0)
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case 1:
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if e.SourceNetmask > net.IPv4len*8 || e.SourceScope > net.IPv4len*8 {
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return errors.New("dns: bad netmask")
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}
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addr := make(net.IP, net.IPv4len)
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copy(addr, b[4:])
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e.Address = addr.To16()
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case 2:
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if e.SourceNetmask > net.IPv6len*8 || e.SourceScope > net.IPv6len*8 {
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return errors.New("dns: bad netmask")
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}
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addr := make(net.IP, net.IPv6len)
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copy(addr, b[4:])
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e.Address = addr
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default:
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return errors.New("dns: bad address family")
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}
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return nil
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}
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func (e *EDNS0_SUBNET) String() (s string) {
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if e.Address == nil {
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s = "<nil>"
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} else if e.Address.To4() != nil {
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s = e.Address.String()
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} else {
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s = "[" + e.Address.String() + "]"
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}
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s += "/" + strconv.Itoa(int(e.SourceNetmask)) + "/" + strconv.Itoa(int(e.SourceScope))
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return
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}
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func (e *EDNS0_SUBNET) copy() EDNS0 {
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return &EDNS0_SUBNET{
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e.Code,
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e.Family,
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e.SourceNetmask,
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e.SourceScope,
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e.Address,
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}
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}
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// The EDNS0_COOKIE option is used to add a DNS Cookie to a message.
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//
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// o := new(dns.OPT)
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// o.Hdr.Name = "."
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// o.Hdr.Rrtype = dns.TypeOPT
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// e := new(dns.EDNS0_COOKIE)
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// e.Code = dns.EDNS0COOKIE
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// e.Cookie = "24a5ac.."
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// o.Option = append(o.Option, e)
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//
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// The Cookie field consists out of a client cookie (RFC 7873 Section 4), that is
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// always 8 bytes. It may then optionally be followed by the server cookie. The server
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// cookie is of variable length, 8 to a maximum of 32 bytes. In other words:
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//
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// cCookie := o.Cookie[:16]
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// sCookie := o.Cookie[16:]
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//
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// There is no guarantee that the Cookie string has a specific length.
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type EDNS0_COOKIE struct {
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Code uint16 // Always EDNS0COOKIE
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Cookie string // Hex-encoded cookie data
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}
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func (e *EDNS0_COOKIE) pack() ([]byte, error) {
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h, err := hex.DecodeString(e.Cookie)
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if err != nil {
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return nil, err
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}
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return h, nil
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}
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// Option implements the EDNS0 interface.
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func (e *EDNS0_COOKIE) Option() uint16 { return EDNS0COOKIE }
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func (e *EDNS0_COOKIE) unpack(b []byte) error { e.Cookie = hex.EncodeToString(b); return nil }
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func (e *EDNS0_COOKIE) String() string { return e.Cookie }
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func (e *EDNS0_COOKIE) copy() EDNS0 { return &EDNS0_COOKIE{e.Code, e.Cookie} }
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// The EDNS0_UL (Update Lease) (draft RFC) option is used to tell the server to set
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// an expiration on an update RR. This is helpful for clients that cannot clean
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// up after themselves. This is a draft RFC and more information can be found at
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// https://tools.ietf.org/html/draft-sekar-dns-ul-02
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//
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// o := new(dns.OPT)
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// o.Hdr.Name = "."
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// o.Hdr.Rrtype = dns.TypeOPT
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// e := new(dns.EDNS0_UL)
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// e.Code = dns.EDNS0UL
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// e.Lease = 120 // in seconds
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// o.Option = append(o.Option, e)
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type EDNS0_UL struct {
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Code uint16 // Always EDNS0UL
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Lease uint32
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KeyLease uint32
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}
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// Option implements the EDNS0 interface.
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func (e *EDNS0_UL) Option() uint16 { return EDNS0UL }
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func (e *EDNS0_UL) String() string { return fmt.Sprintf("%d %d", e.Lease, e.KeyLease) }
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func (e *EDNS0_UL) copy() EDNS0 { return &EDNS0_UL{e.Code, e.Lease, e.KeyLease} }
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// Copied: http://golang.org/src/pkg/net/dnsmsg.go
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func (e *EDNS0_UL) pack() ([]byte, error) {
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var b []byte
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if e.KeyLease == 0 {
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b = make([]byte, 4)
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} else {
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b = make([]byte, 8)
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binary.BigEndian.PutUint32(b[4:], e.KeyLease)
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}
|
|
binary.BigEndian.PutUint32(b, e.Lease)
|
|
return b, nil
|
|
}
|
|
|
|
func (e *EDNS0_UL) unpack(b []byte) error {
|
|
switch len(b) {
|
|
case 4:
|
|
e.KeyLease = 0
|
|
case 8:
|
|
e.KeyLease = binary.BigEndian.Uint32(b[4:])
|
|
default:
|
|
return ErrBuf
|
|
}
|
|
e.Lease = binary.BigEndian.Uint32(b)
|
|
return nil
|
|
}
|
|
|
|
// EDNS0_LLQ stands for Long Lived Queries: http://tools.ietf.org/html/draft-sekar-dns-llq-01
|
|
// Implemented for completeness, as the EDNS0 type code is assigned.
|
|
type EDNS0_LLQ struct {
|
|
Code uint16 // Always EDNS0LLQ
|
|
Version uint16
|
|
Opcode uint16
|
|
Error uint16
|
|
Id uint64
|
|
LeaseLife uint32
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_LLQ) Option() uint16 { return EDNS0LLQ }
|
|
|
|
func (e *EDNS0_LLQ) pack() ([]byte, error) {
|
|
b := make([]byte, 18)
|
|
binary.BigEndian.PutUint16(b[0:], e.Version)
|
|
binary.BigEndian.PutUint16(b[2:], e.Opcode)
|
|
binary.BigEndian.PutUint16(b[4:], e.Error)
|
|
binary.BigEndian.PutUint64(b[6:], e.Id)
|
|
binary.BigEndian.PutUint32(b[14:], e.LeaseLife)
|
|
return b, nil
|
|
}
|
|
|
|
func (e *EDNS0_LLQ) unpack(b []byte) error {
|
|
if len(b) < 18 {
|
|
return ErrBuf
|
|
}
|
|
e.Version = binary.BigEndian.Uint16(b[0:])
|
|
e.Opcode = binary.BigEndian.Uint16(b[2:])
|
|
e.Error = binary.BigEndian.Uint16(b[4:])
|
|
e.Id = binary.BigEndian.Uint64(b[6:])
|
|
e.LeaseLife = binary.BigEndian.Uint32(b[14:])
|
|
return nil
|
|
}
|
|
|
|
func (e *EDNS0_LLQ) String() string {
|
|
s := strconv.FormatUint(uint64(e.Version), 10) + " " + strconv.FormatUint(uint64(e.Opcode), 10) +
|
|
" " + strconv.FormatUint(uint64(e.Error), 10) + " " + strconv.FormatUint(e.Id, 10) +
|
|
" " + strconv.FormatUint(uint64(e.LeaseLife), 10)
|
|
return s
|
|
}
|
|
|
|
func (e *EDNS0_LLQ) copy() EDNS0 {
|
|
return &EDNS0_LLQ{e.Code, e.Version, e.Opcode, e.Error, e.Id, e.LeaseLife}
|
|
}
|
|
|
|
// EDNS0_DAU implements the EDNS0 "DNSSEC Algorithm Understood" option. See RFC 6975.
|
|
type EDNS0_DAU struct {
|
|
Code uint16 // Always EDNS0DAU
|
|
AlgCode []uint8
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_DAU) Option() uint16 { return EDNS0DAU }
|
|
func (e *EDNS0_DAU) pack() ([]byte, error) { return cloneSlice(e.AlgCode), nil }
|
|
func (e *EDNS0_DAU) unpack(b []byte) error { e.AlgCode = cloneSlice(b); return nil }
|
|
|
|
func (e *EDNS0_DAU) String() string {
|
|
s := ""
|
|
for _, alg := range e.AlgCode {
|
|
if a, ok := AlgorithmToString[alg]; ok {
|
|
s += " " + a
|
|
} else {
|
|
s += " " + strconv.Itoa(int(alg))
|
|
}
|
|
}
|
|
return s
|
|
}
|
|
func (e *EDNS0_DAU) copy() EDNS0 { return &EDNS0_DAU{e.Code, e.AlgCode} }
|
|
|
|
// EDNS0_DHU implements the EDNS0 "DS Hash Understood" option. See RFC 6975.
|
|
type EDNS0_DHU struct {
|
|
Code uint16 // Always EDNS0DHU
|
|
AlgCode []uint8
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_DHU) Option() uint16 { return EDNS0DHU }
|
|
func (e *EDNS0_DHU) pack() ([]byte, error) { return cloneSlice(e.AlgCode), nil }
|
|
func (e *EDNS0_DHU) unpack(b []byte) error { e.AlgCode = cloneSlice(b); return nil }
|
|
|
|
func (e *EDNS0_DHU) String() string {
|
|
s := ""
|
|
for _, alg := range e.AlgCode {
|
|
if a, ok := HashToString[alg]; ok {
|
|
s += " " + a
|
|
} else {
|
|
s += " " + strconv.Itoa(int(alg))
|
|
}
|
|
}
|
|
return s
|
|
}
|
|
func (e *EDNS0_DHU) copy() EDNS0 { return &EDNS0_DHU{e.Code, e.AlgCode} }
|
|
|
|
// EDNS0_N3U implements the EDNS0 "NSEC3 Hash Understood" option. See RFC 6975.
|
|
type EDNS0_N3U struct {
|
|
Code uint16 // Always EDNS0N3U
|
|
AlgCode []uint8
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_N3U) Option() uint16 { return EDNS0N3U }
|
|
func (e *EDNS0_N3U) pack() ([]byte, error) { return cloneSlice(e.AlgCode), nil }
|
|
func (e *EDNS0_N3U) unpack(b []byte) error { e.AlgCode = cloneSlice(b); return nil }
|
|
|
|
func (e *EDNS0_N3U) String() string {
|
|
// Re-use the hash map
|
|
s := ""
|
|
for _, alg := range e.AlgCode {
|
|
if a, ok := HashToString[alg]; ok {
|
|
s += " " + a
|
|
} else {
|
|
s += " " + strconv.Itoa(int(alg))
|
|
}
|
|
}
|
|
return s
|
|
}
|
|
func (e *EDNS0_N3U) copy() EDNS0 { return &EDNS0_N3U{e.Code, e.AlgCode} }
|
|
|
|
// EDNS0_EXPIRE implements the EDNS0 option as described in RFC 7314.
|
|
type EDNS0_EXPIRE struct {
|
|
Code uint16 // Always EDNS0EXPIRE
|
|
Expire uint32
|
|
Empty bool // Empty is used to signal an empty Expire option in a backwards compatible way, it's not used on the wire.
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_EXPIRE) Option() uint16 { return EDNS0EXPIRE }
|
|
func (e *EDNS0_EXPIRE) copy() EDNS0 { return &EDNS0_EXPIRE{e.Code, e.Expire, e.Empty} }
|
|
|
|
func (e *EDNS0_EXPIRE) pack() ([]byte, error) {
|
|
if e.Empty {
|
|
return []byte{}, nil
|
|
}
|
|
b := make([]byte, 4)
|
|
binary.BigEndian.PutUint32(b, e.Expire)
|
|
return b, nil
|
|
}
|
|
|
|
func (e *EDNS0_EXPIRE) unpack(b []byte) error {
|
|
if len(b) == 0 {
|
|
// zero-length EXPIRE query, see RFC 7314 Section 2
|
|
e.Empty = true
|
|
return nil
|
|
}
|
|
if len(b) < 4 {
|
|
return ErrBuf
|
|
}
|
|
e.Expire = binary.BigEndian.Uint32(b)
|
|
e.Empty = false
|
|
return nil
|
|
}
|
|
|
|
func (e *EDNS0_EXPIRE) String() (s string) {
|
|
if e.Empty {
|
|
return ""
|
|
}
|
|
return strconv.FormatUint(uint64(e.Expire), 10)
|
|
}
|
|
|
|
// The EDNS0_LOCAL option is used for local/experimental purposes. The option
|
|
// code is recommended to be within the range [EDNS0LOCALSTART, EDNS0LOCALEND]
|
|
// (RFC6891), although any unassigned code can actually be used. The content of
|
|
// the option is made available in Data, unaltered.
|
|
// Basic use pattern for creating a local option:
|
|
//
|
|
// o := new(dns.OPT)
|
|
// o.Hdr.Name = "."
|
|
// o.Hdr.Rrtype = dns.TypeOPT
|
|
// e := new(dns.EDNS0_LOCAL)
|
|
// e.Code = dns.EDNS0LOCALSTART
|
|
// e.Data = []byte{72, 82, 74}
|
|
// o.Option = append(o.Option, e)
|
|
type EDNS0_LOCAL struct {
|
|
Code uint16
|
|
Data []byte
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_LOCAL) Option() uint16 { return e.Code }
|
|
|
|
func (e *EDNS0_LOCAL) String() string {
|
|
return strconv.FormatInt(int64(e.Code), 10) + ":0x" + hex.EncodeToString(e.Data)
|
|
}
|
|
|
|
func (e *EDNS0_LOCAL) copy() EDNS0 {
|
|
return &EDNS0_LOCAL{e.Code, cloneSlice(e.Data)}
|
|
}
|
|
|
|
func (e *EDNS0_LOCAL) pack() ([]byte, error) {
|
|
return cloneSlice(e.Data), nil
|
|
}
|
|
|
|
func (e *EDNS0_LOCAL) unpack(b []byte) error {
|
|
e.Data = cloneSlice(b)
|
|
return nil
|
|
}
|
|
|
|
// EDNS0_TCP_KEEPALIVE is an EDNS0 option that instructs the server to keep
|
|
// the TCP connection alive. See RFC 7828.
|
|
type EDNS0_TCP_KEEPALIVE struct {
|
|
Code uint16 // Always EDNSTCPKEEPALIVE
|
|
|
|
// Timeout is an idle timeout value for the TCP connection, specified in
|
|
// units of 100 milliseconds, encoded in network byte order. If set to 0,
|
|
// pack will return a nil slice.
|
|
Timeout uint16
|
|
|
|
// Length is the option's length.
|
|
// Deprecated: this field is deprecated and is always equal to 0.
|
|
Length uint16
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_TCP_KEEPALIVE) Option() uint16 { return EDNS0TCPKEEPALIVE }
|
|
|
|
func (e *EDNS0_TCP_KEEPALIVE) pack() ([]byte, error) {
|
|
if e.Timeout > 0 {
|
|
b := make([]byte, 2)
|
|
binary.BigEndian.PutUint16(b, e.Timeout)
|
|
return b, nil
|
|
}
|
|
return nil, nil
|
|
}
|
|
|
|
func (e *EDNS0_TCP_KEEPALIVE) unpack(b []byte) error {
|
|
switch len(b) {
|
|
case 0:
|
|
case 2:
|
|
e.Timeout = binary.BigEndian.Uint16(b)
|
|
default:
|
|
return fmt.Errorf("dns: length mismatch, want 0/2 but got %d", len(b))
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (e *EDNS0_TCP_KEEPALIVE) String() string {
|
|
s := "use tcp keep-alive"
|
|
if e.Timeout == 0 {
|
|
s += ", timeout omitted"
|
|
} else {
|
|
s += fmt.Sprintf(", timeout %dms", e.Timeout*100)
|
|
}
|
|
return s
|
|
}
|
|
|
|
func (e *EDNS0_TCP_KEEPALIVE) copy() EDNS0 { return &EDNS0_TCP_KEEPALIVE{e.Code, e.Timeout, e.Length} }
|
|
|
|
// EDNS0_PADDING option is used to add padding to a request/response. The default
|
|
// value of padding SHOULD be 0x0 but other values MAY be used, for instance if
|
|
// compression is applied before encryption which may break signatures.
|
|
type EDNS0_PADDING struct {
|
|
Padding []byte
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_PADDING) Option() uint16 { return EDNS0PADDING }
|
|
func (e *EDNS0_PADDING) pack() ([]byte, error) { return cloneSlice(e.Padding), nil }
|
|
func (e *EDNS0_PADDING) unpack(b []byte) error { e.Padding = cloneSlice(b); return nil }
|
|
func (e *EDNS0_PADDING) String() string { return fmt.Sprintf("%0X", e.Padding) }
|
|
func (e *EDNS0_PADDING) copy() EDNS0 { return &EDNS0_PADDING{cloneSlice(e.Padding)} }
|
|
|
|
// Extended DNS Error Codes (RFC 8914).
|
|
const (
|
|
ExtendedErrorCodeOther uint16 = iota
|
|
ExtendedErrorCodeUnsupportedDNSKEYAlgorithm
|
|
ExtendedErrorCodeUnsupportedDSDigestType
|
|
ExtendedErrorCodeStaleAnswer
|
|
ExtendedErrorCodeForgedAnswer
|
|
ExtendedErrorCodeDNSSECIndeterminate
|
|
ExtendedErrorCodeDNSBogus
|
|
ExtendedErrorCodeSignatureExpired
|
|
ExtendedErrorCodeSignatureNotYetValid
|
|
ExtendedErrorCodeDNSKEYMissing
|
|
ExtendedErrorCodeRRSIGsMissing
|
|
ExtendedErrorCodeNoZoneKeyBitSet
|
|
ExtendedErrorCodeNSECMissing
|
|
ExtendedErrorCodeCachedError
|
|
ExtendedErrorCodeNotReady
|
|
ExtendedErrorCodeBlocked
|
|
ExtendedErrorCodeCensored
|
|
ExtendedErrorCodeFiltered
|
|
ExtendedErrorCodeProhibited
|
|
ExtendedErrorCodeStaleNXDOMAINAnswer
|
|
ExtendedErrorCodeNotAuthoritative
|
|
ExtendedErrorCodeNotSupported
|
|
ExtendedErrorCodeNoReachableAuthority
|
|
ExtendedErrorCodeNetworkError
|
|
ExtendedErrorCodeInvalidData
|
|
ExtendedErrorCodeSignatureExpiredBeforeValid
|
|
ExtendedErrorCodeTooEarly
|
|
ExtendedErrorCodeUnsupportedNSEC3IterValue
|
|
ExtendedErrorCodeUnableToConformToPolicy
|
|
ExtendedErrorCodeSynthesized
|
|
ExtendedErrorCodeInvalidQueryType
|
|
)
|
|
|
|
// ExtendedErrorCodeToString maps extended error info codes to a human readable
|
|
// description.
|
|
var ExtendedErrorCodeToString = map[uint16]string{
|
|
ExtendedErrorCodeOther: "Other",
|
|
ExtendedErrorCodeUnsupportedDNSKEYAlgorithm: "Unsupported DNSKEY Algorithm",
|
|
ExtendedErrorCodeUnsupportedDSDigestType: "Unsupported DS Digest Type",
|
|
ExtendedErrorCodeStaleAnswer: "Stale Answer",
|
|
ExtendedErrorCodeForgedAnswer: "Forged Answer",
|
|
ExtendedErrorCodeDNSSECIndeterminate: "DNSSEC Indeterminate",
|
|
ExtendedErrorCodeDNSBogus: "DNSSEC Bogus",
|
|
ExtendedErrorCodeSignatureExpired: "Signature Expired",
|
|
ExtendedErrorCodeSignatureNotYetValid: "Signature Not Yet Valid",
|
|
ExtendedErrorCodeDNSKEYMissing: "DNSKEY Missing",
|
|
ExtendedErrorCodeRRSIGsMissing: "RRSIGs Missing",
|
|
ExtendedErrorCodeNoZoneKeyBitSet: "No Zone Key Bit Set",
|
|
ExtendedErrorCodeNSECMissing: "NSEC Missing",
|
|
ExtendedErrorCodeCachedError: "Cached Error",
|
|
ExtendedErrorCodeNotReady: "Not Ready",
|
|
ExtendedErrorCodeBlocked: "Blocked",
|
|
ExtendedErrorCodeCensored: "Censored",
|
|
ExtendedErrorCodeFiltered: "Filtered",
|
|
ExtendedErrorCodeProhibited: "Prohibited",
|
|
ExtendedErrorCodeStaleNXDOMAINAnswer: "Stale NXDOMAIN Answer",
|
|
ExtendedErrorCodeNotAuthoritative: "Not Authoritative",
|
|
ExtendedErrorCodeNotSupported: "Not Supported",
|
|
ExtendedErrorCodeNoReachableAuthority: "No Reachable Authority",
|
|
ExtendedErrorCodeNetworkError: "Network Error",
|
|
ExtendedErrorCodeInvalidData: "Invalid Data",
|
|
ExtendedErrorCodeSignatureExpiredBeforeValid: "Signature Expired Before Valid",
|
|
ExtendedErrorCodeTooEarly: "Too Early",
|
|
ExtendedErrorCodeUnsupportedNSEC3IterValue: "Unsupported NSEC3 Iterations Value",
|
|
ExtendedErrorCodeUnableToConformToPolicy: "Unable To Conform To Policy",
|
|
ExtendedErrorCodeSynthesized: "Synthesized",
|
|
ExtendedErrorCodeInvalidQueryType: "Invalid Query Type",
|
|
}
|
|
|
|
// StringToExtendedErrorCode is a map from human readable descriptions to
|
|
// extended error info codes.
|
|
var StringToExtendedErrorCode = reverseInt16(ExtendedErrorCodeToString)
|
|
|
|
// EDNS0_EDE option is used to return additional information about the cause of
|
|
// DNS errors.
|
|
type EDNS0_EDE struct {
|
|
InfoCode uint16
|
|
ExtraText string
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_EDE) Option() uint16 { return EDNS0EDE }
|
|
func (e *EDNS0_EDE) copy() EDNS0 { return &EDNS0_EDE{e.InfoCode, e.ExtraText} }
|
|
|
|
func (e *EDNS0_EDE) String() string {
|
|
info := strconv.FormatUint(uint64(e.InfoCode), 10)
|
|
if s, ok := ExtendedErrorCodeToString[e.InfoCode]; ok {
|
|
info += fmt.Sprintf(" (%s)", s)
|
|
}
|
|
return fmt.Sprintf("%s: (%s)", info, e.ExtraText)
|
|
}
|
|
|
|
func (e *EDNS0_EDE) pack() ([]byte, error) {
|
|
b := make([]byte, 2+len(e.ExtraText))
|
|
binary.BigEndian.PutUint16(b[0:], e.InfoCode)
|
|
copy(b[2:], e.ExtraText)
|
|
return b, nil
|
|
}
|
|
|
|
func (e *EDNS0_EDE) unpack(b []byte) error {
|
|
if len(b) < 2 {
|
|
return ErrBuf
|
|
}
|
|
e.InfoCode = binary.BigEndian.Uint16(b[0:])
|
|
e.ExtraText = string(b[2:])
|
|
return nil
|
|
}
|
|
|
|
// The EDNS0_ESU option for ENUM Source-URI Extension
|
|
type EDNS0_ESU struct {
|
|
Code uint16
|
|
Uri string
|
|
}
|
|
|
|
// Option implements the EDNS0 interface.
|
|
func (e *EDNS0_ESU) Option() uint16 { return EDNS0ESU }
|
|
func (e *EDNS0_ESU) String() string { return e.Uri }
|
|
func (e *EDNS0_ESU) copy() EDNS0 { return &EDNS0_ESU{e.Code, e.Uri} }
|
|
func (e *EDNS0_ESU) pack() ([]byte, error) { return []byte(e.Uri), nil }
|
|
func (e *EDNS0_ESU) unpack(b []byte) error {
|
|
e.Uri = string(b)
|
|
return nil
|
|
}
|