mirror of
https://github.com/xvzc/SpoofDPI.git
synced 2024-12-22 06:15:51 +00:00
feat: add IPv6 support (#161)
* Add support for IPv6 lookups. * Refactor DNSResolver. * Make listener support IPv6.
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27
dns/addrselect/LICENSE
Normal file
27
dns/addrselect/LICENSE
Normal file
@ -0,0 +1,27 @@
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Copyright 2009 The Go Authors.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are
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met:
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* Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above
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copyright notice, this list of conditions and the following disclaimer
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in the documentation and/or other materials provided with the
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distribution.
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* Neither the name of Google LLC nor the names of its
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contributors may be used to endorse or promote products derived from
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this software without specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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377
dns/addrselect/addrselect.go
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377
dns/addrselect/addrselect.go
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@ -0,0 +1,377 @@
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package addrselect
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import (
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"net"
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"net/netip"
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"sort"
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)
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// Copyright 2015 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Minimal RFC 6724 address selection.
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func SortByRFC6724(addrs []net.IPAddr) {
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if len(addrs) < 2 {
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return
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}
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sortByRFC6724withSrcs(addrs, srcAddrs(addrs))
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}
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func sortByRFC6724withSrcs(addrs []net.IPAddr, srcs []netip.Addr) {
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if len(addrs) != len(srcs) {
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panic("internal error")
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}
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addrAttr := make([]ipAttr, len(addrs))
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srcAttr := make([]ipAttr, len(srcs))
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for i, v := range addrs {
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addrAttrIP, _ := netip.AddrFromSlice(v.IP)
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addrAttr[i] = ipAttrOf(addrAttrIP)
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srcAttr[i] = ipAttrOf(srcs[i])
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}
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sort.Stable(&byRFC6724{
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addrs: addrs,
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addrAttr: addrAttr,
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srcs: srcs,
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srcAttr: srcAttr,
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})
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}
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// srcAddrs tries to UDP-connect to each address to see if it has a
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// route. (This doesn't send any packets). The destination port
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// number is irrelevant.
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func srcAddrs(addrs []net.IPAddr) []netip.Addr {
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srcs := make([]netip.Addr, len(addrs))
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dst := net.UDPAddr{Port: 9}
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for i := range addrs {
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dst.IP = addrs[i].IP
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dst.Zone = addrs[i].Zone
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c, err := net.DialUDP("udp", nil, &dst)
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if err == nil {
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if src, ok := c.LocalAddr().(*net.UDPAddr); ok {
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srcs[i], _ = netip.AddrFromSlice(src.IP)
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}
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c.Close()
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}
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}
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return srcs
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}
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type ipAttr struct {
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Scope scope
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Precedence uint8
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Label uint8
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}
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func ipAttrOf(ip netip.Addr) ipAttr {
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if !ip.IsValid() {
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return ipAttr{}
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}
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match := rfc6724policyTable.Classify(ip)
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return ipAttr{
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Scope: classifyScope(ip),
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Precedence: match.Precedence,
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Label: match.Label,
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}
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}
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type byRFC6724 struct {
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addrs []net.IPAddr // addrs to sort
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addrAttr []ipAttr
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srcs []netip.Addr // or not valid addr if unreachable
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srcAttr []ipAttr
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}
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func (s *byRFC6724) Len() int { return len(s.addrs) }
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func (s *byRFC6724) Swap(i, j int) {
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s.addrs[i], s.addrs[j] = s.addrs[j], s.addrs[i]
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s.srcs[i], s.srcs[j] = s.srcs[j], s.srcs[i]
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s.addrAttr[i], s.addrAttr[j] = s.addrAttr[j], s.addrAttr[i]
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s.srcAttr[i], s.srcAttr[j] = s.srcAttr[j], s.srcAttr[i]
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}
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// Less reports whether i is a better destination address for this
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// host than j.
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//
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// The algorithm and variable names comes from RFC 6724 section 6.
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func (s *byRFC6724) Less(i, j int) bool {
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DA := s.addrs[i].IP
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DB := s.addrs[j].IP
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SourceDA := s.srcs[i]
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SourceDB := s.srcs[j]
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attrDA := &s.addrAttr[i]
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attrDB := &s.addrAttr[j]
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attrSourceDA := &s.srcAttr[i]
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attrSourceDB := &s.srcAttr[j]
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const preferDA = true
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const preferDB = false
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// Rule 1: Avoid unusable destinations.
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// If DB is known to be unreachable or if Source(DB) is undefined, then
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// prefer DA. Similarly, if DA is known to be unreachable or if
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// Source(DA) is undefined, then prefer DB.
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if !SourceDA.IsValid() && !SourceDB.IsValid() {
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return false // "equal"
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}
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if !SourceDB.IsValid() {
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return preferDA
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}
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if !SourceDA.IsValid() {
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return preferDB
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}
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// Rule 2: Prefer matching scope.
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// If Scope(DA) = Scope(Source(DA)) and Scope(DB) <> Scope(Source(DB)),
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// then prefer DA. Similarly, if Scope(DA) <> Scope(Source(DA)) and
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// Scope(DB) = Scope(Source(DB)), then prefer DB.
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if attrDA.Scope == attrSourceDA.Scope && attrDB.Scope != attrSourceDB.Scope {
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return preferDA
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}
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if attrDA.Scope != attrSourceDA.Scope && attrDB.Scope == attrSourceDB.Scope {
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return preferDB
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}
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// Rule 3: Avoid deprecated addresses.
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// If Source(DA) is deprecated and Source(DB) is not, then prefer DB.
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// Similarly, if Source(DA) is not deprecated and Source(DB) is
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// deprecated, then prefer DA.
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// TODO(bradfitz): implement? low priority for now.
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// Rule 4: Prefer home addresses.
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// If Source(DA) is simultaneously a home address and care-of address
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// and Source(DB) is not, then prefer DA. Similarly, if Source(DB) is
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// simultaneously a home address and care-of address and Source(DA) is
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// not, then prefer DB.
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// TODO(bradfitz): implement? low priority for now.
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// Rule 5: Prefer matching label.
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// If Label(Source(DA)) = Label(DA) and Label(Source(DB)) <> Label(DB),
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// then prefer DA. Similarly, if Label(Source(DA)) <> Label(DA) and
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// Label(Source(DB)) = Label(DB), then prefer DB.
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if attrSourceDA.Label == attrDA.Label &&
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attrSourceDB.Label != attrDB.Label {
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return preferDA
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}
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if attrSourceDA.Label != attrDA.Label &&
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attrSourceDB.Label == attrDB.Label {
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return preferDB
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}
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// Rule 6: Prefer higher precedence.
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// If Precedence(DA) > Precedence(DB), then prefer DA. Similarly, if
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// Precedence(DA) < Precedence(DB), then prefer DB.
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if attrDA.Precedence > attrDB.Precedence {
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return preferDA
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}
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if attrDA.Precedence < attrDB.Precedence {
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return preferDB
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}
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// Rule 7: Prefer native transport.
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// If DA is reached via an encapsulating transition mechanism (e.g.,
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// IPv6 in IPv4) and DB is not, then prefer DB. Similarly, if DB is
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// reached via encapsulation and DA is not, then prefer DA.
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// TODO(bradfitz): implement? low priority for now.
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// Rule 8: Prefer smaller scope.
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// If Scope(DA) < Scope(DB), then prefer DA. Similarly, if Scope(DA) >
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// Scope(DB), then prefer DB.
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if attrDA.Scope < attrDB.Scope {
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return preferDA
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}
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if attrDA.Scope > attrDB.Scope {
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return preferDB
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}
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// Rule 9: Use the longest matching prefix.
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// When DA and DB belong to the same address family (both are IPv6 or
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// both are IPv4 [but see below]): If CommonPrefixLen(Source(DA), DA) >
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// CommonPrefixLen(Source(DB), DB), then prefer DA. Similarly, if
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// CommonPrefixLen(Source(DA), DA) < CommonPrefixLen(Source(DB), DB),
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// then prefer DB.
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//
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// However, applying this rule to IPv4 addresses causes
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// problems (see issues 13283 and 18518), so limit to IPv6.
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if DA.To4() == nil && DB.To4() == nil {
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commonA := commonPrefixLen(SourceDA, DA)
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commonB := commonPrefixLen(SourceDB, DB)
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if commonA > commonB {
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return preferDA
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}
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if commonA < commonB {
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return preferDB
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}
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}
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// Rule 10: Otherwise, leave the order unchanged.
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// If DA preceded DB in the original list, prefer DA.
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// Otherwise, prefer DB.
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return false // "equal"
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}
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type policyTableEntry struct {
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Prefix netip.Prefix
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Precedence uint8
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Label uint8
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}
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type policyTable []policyTableEntry
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// RFC 6724 section 2.1.
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// Items are sorted by the size of their Prefix.Mask.Size,
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var rfc6724policyTable = policyTable{
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{
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// "::1/128"
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Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01}), 128),
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Precedence: 50,
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Label: 0,
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},
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{
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// "::ffff:0:0/96"
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// IPv4-compatible, etc.
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Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff}), 96),
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Precedence: 35,
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Label: 4,
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},
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{
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// "::/96"
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Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{}), 96),
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Precedence: 1,
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Label: 3,
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},
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{
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// "2001::/32"
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// Teredo
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Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0x20, 0x01}), 32),
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Precedence: 5,
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Label: 5,
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},
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{
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// "2002::/16"
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// 6to4
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Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0x20, 0x02}), 16),
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Precedence: 30,
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Label: 2,
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},
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{
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// "3ffe::/16"
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Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0x3f, 0xfe}), 16),
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Precedence: 1,
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Label: 12,
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},
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{
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// "fec0::/10"
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Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0xfe, 0xc0}), 10),
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Precedence: 1,
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Label: 11,
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},
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{
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// "fc00::/7"
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Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0xfc}), 7),
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Precedence: 3,
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Label: 13,
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},
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{
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// "::/0"
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Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{}), 0),
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Precedence: 40,
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Label: 1,
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},
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}
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// Classify returns the policyTableEntry of the entry with the longest
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// matching prefix that contains ip.
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// The table t must be sorted from largest mask size to smallest.
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func (t policyTable) Classify(ip netip.Addr) policyTableEntry {
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// Prefix.Contains() will not match an IPv6 prefix for an IPv4 address.
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if ip.Is4() {
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ip = netip.AddrFrom16(ip.As16())
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}
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for _, ent := range t {
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if ent.Prefix.Contains(ip) {
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return ent
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}
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}
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return policyTableEntry{}
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}
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// RFC 6724 section 3.1.
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type scope uint8
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const (
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scopeInterfaceLocal scope = 0x1
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scopeLinkLocal scope = 0x2
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scopeAdminLocal scope = 0x4
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scopeSiteLocal scope = 0x5
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scopeOrgLocal scope = 0x8
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scopeGlobal scope = 0xe
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)
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func classifyScope(ip netip.Addr) scope {
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if ip.IsLoopback() || ip.IsLinkLocalUnicast() {
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return scopeLinkLocal
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}
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ipv6 := ip.Is6() && !ip.Is4In6()
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ipv6AsBytes := ip.As16()
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if ipv6 && ip.IsMulticast() {
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return scope(ipv6AsBytes[1] & 0xf)
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}
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// Site-local addresses are defined in RFC 3513 section 2.5.6
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// (and deprecated in RFC 3879).
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if ipv6 && ipv6AsBytes[0] == 0xfe && ipv6AsBytes[1]&0xc0 == 0xc0 {
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return scopeSiteLocal
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}
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return scopeGlobal
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}
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// commonPrefixLen reports the length of the longest prefix (looking
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// at the most significant, or leftmost, bits) that the
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// two addresses have in common, up to the length of a's prefix (i.e.,
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// the portion of the address not including the interface ID).
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//
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// If a or b is an IPv4 address as an IPv6 address, the IPv4 addresses
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// are compared (with max common prefix length of 32).
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// If a and b are different IP versions, 0 is returned.
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//
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// See https://tools.ietf.org/html/rfc6724#section-2.2
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func commonPrefixLen(a netip.Addr, b net.IP) (cpl int) {
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if b4 := b.To4(); b4 != nil {
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b = b4
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}
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aAsSlice := a.AsSlice()
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if len(aAsSlice) != len(b) {
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return 0
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}
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// If IPv6, only up to the prefix (first 64 bits)
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if len(aAsSlice) > 8 {
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aAsSlice = aAsSlice[:8]
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b = b[:8]
|
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}
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for len(aAsSlice) > 0 {
|
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if aAsSlice[0] == b[0] {
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cpl += 8
|
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aAsSlice = aAsSlice[1:]
|
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b = b[1:]
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continue
|
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}
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bits := 8
|
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ab, bb := aAsSlice[0], b[0]
|
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for {
|
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ab >>= 1
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bb >>= 1
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bits--
|
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if ab == bb {
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cpl += bits
|
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return
|
||||
}
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}
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}
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return
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}
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314
dns/dns.go
314
dns/dns.go
@ -3,108 +3,256 @@ package dns
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import (
|
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"context"
|
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"errors"
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"net"
|
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"regexp"
|
||||
"strconv"
|
||||
"time"
|
||||
|
||||
"fmt"
|
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"github.com/miekg/dns"
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log "github.com/sirupsen/logrus"
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"github.com/xvzc/SpoofDPI/dns/addrselect"
|
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"github.com/xvzc/SpoofDPI/util"
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"net"
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"net/netip"
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"strconv"
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"sync"
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"time"
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)
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type DnsResolver struct {
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host string
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port string
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enableDoh bool
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type client interface {
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Resolve(ctx context.Context, host string) ([]net.IPAddr, error)
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String() string
|
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}
|
||||
|
||||
func NewResolver(config *util.Config) *DnsResolver {
|
||||
return &DnsResolver{
|
||||
host: *config.DnsAddr,
|
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port: strconv.Itoa(*config.DnsPort),
|
||||
enableDoh: *config.EnableDoh,
|
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type Resolver struct {
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||||
host string
|
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port string
|
||||
enableDoh bool
|
||||
systemClient client
|
||||
customClient client
|
||||
}
|
||||
|
||||
func NewResolver(config *util.Config) *Resolver {
|
||||
addr := *config.DnsAddr
|
||||
port := strconv.Itoa(*config.DnsPort)
|
||||
server := net.JoinHostPort(addr, port)
|
||||
|
||||
var systemClient client
|
||||
if config.AllowedPatterns != nil {
|
||||
systemClient = NewSystemClient()
|
||||
}
|
||||
|
||||
var customClient client
|
||||
if *config.EnableDoh {
|
||||
customClient = NewDoHClient(addr)
|
||||
} else {
|
||||
customClient = NewCustomClient(server)
|
||||
}
|
||||
|
||||
return &Resolver{
|
||||
host: *config.DnsAddr,
|
||||
port: port,
|
||||
enableDoh: *config.EnableDoh,
|
||||
systemClient: systemClient,
|
||||
customClient: customClient,
|
||||
}
|
||||
}
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||||
|
||||
func (d *DnsResolver) Lookup(domain string, useSystemDns bool) (string, error) {
|
||||
ipRegex := "^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$"
|
||||
|
||||
if r, _ := regexp.MatchString(ipRegex, domain); r {
|
||||
func (d *Resolver) Lookup(domain string, useSystemDns bool) (string, error) {
|
||||
if _, err := parseAddr(domain); err == nil {
|
||||
return domain, nil
|
||||
}
|
||||
|
||||
if useSystemDns {
|
||||
log.Debug("[DNS] ", domain, " resolving with system dns")
|
||||
return systemLookup(domain)
|
||||
}
|
||||
|
||||
if d.enableDoh {
|
||||
log.Debug("[DNS] ", domain, " resolving with dns over https")
|
||||
return dohLookup(d.host, domain)
|
||||
}
|
||||
|
||||
log.Debug("[DNS] ", domain, " resolving with custom dns")
|
||||
return customLookup(d.host, d.port, domain)
|
||||
}
|
||||
|
||||
func customLookup(host string, port string, domain string) (string, error) {
|
||||
|
||||
dnsServer := host + ":" + port
|
||||
|
||||
msg := new(dns.Msg)
|
||||
msg.SetQuestion(dns.Fqdn(domain), dns.TypeA)
|
||||
|
||||
c := new(dns.Client)
|
||||
|
||||
response, _, err := c.Exchange(msg, dnsServer)
|
||||
if err != nil {
|
||||
return "", errors.New("could not resolve the domain(custom)")
|
||||
}
|
||||
|
||||
for _, answer := range response.Answer {
|
||||
if record, ok := answer.(*dns.A); ok {
|
||||
return record.A.String(), nil
|
||||
}
|
||||
}
|
||||
|
||||
return "", errors.New("no record found(custom)")
|
||||
|
||||
}
|
||||
|
||||
func systemLookup(domain string) (string, error) {
|
||||
systemResolver := net.Resolver{PreferGo: true}
|
||||
ips, err := systemResolver.LookupIPAddr(context.Background(), domain)
|
||||
if err != nil {
|
||||
return "", errors.New("could not resolve the domain(system)")
|
||||
}
|
||||
|
||||
for _, ip := range ips {
|
||||
return ip.String(), nil
|
||||
}
|
||||
|
||||
return "", errors.New("no record found(system)")
|
||||
}
|
||||
|
||||
func dohLookup(host string, domain string) (string, error) {
|
||||
clt := d.getClient(useSystemDns)
|
||||
ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
|
||||
defer cancel()
|
||||
|
||||
client := getDOHClient(host)
|
||||
|
||||
msg := new(dns.Msg)
|
||||
msg.SetQuestion(dns.Fqdn(domain), dns.TypeA)
|
||||
|
||||
response, err := client.dohExchange(ctx, msg)
|
||||
log.Debugf("[DNS] resolving %s using %s", domain, clt)
|
||||
t := time.Now()
|
||||
addrs, err := clt.Resolve(ctx, domain)
|
||||
if err != nil {
|
||||
return "", errors.New("could not resolve the domain(doh)")
|
||||
return "", fmt.Errorf("%s: %w", clt, err)
|
||||
}
|
||||
lookupTime := time.Since(t).Milliseconds()
|
||||
|
||||
for _, answer := range response.Answer {
|
||||
if record, ok := answer.(*dns.A); ok {
|
||||
return record.A.String(), nil
|
||||
addr := addrs[0].String()
|
||||
log.Debugf("[DNS] resolved %s to %s in %d ms", domain, addr, lookupTime)
|
||||
return addr, nil
|
||||
}
|
||||
|
||||
func (d *Resolver) getClient(useSystemDns bool) client {
|
||||
if useSystemDns {
|
||||
return d.systemClient
|
||||
} else {
|
||||
return d.customClient
|
||||
}
|
||||
}
|
||||
|
||||
type SystemClient struct {
|
||||
client *net.Resolver
|
||||
}
|
||||
|
||||
func NewSystemClient() *SystemClient {
|
||||
return &SystemClient{
|
||||
client: &net.Resolver{PreferGo: true},
|
||||
}
|
||||
}
|
||||
|
||||
func (c *SystemClient) String() string {
|
||||
return "SystemClient"
|
||||
}
|
||||
|
||||
func (c *SystemClient) Resolve(ctx context.Context, host string) ([]net.IPAddr, error) {
|
||||
addrs, err := c.client.LookupIPAddr(ctx, host)
|
||||
if err != nil {
|
||||
return []net.IPAddr{}, err
|
||||
}
|
||||
return addrs, nil
|
||||
}
|
||||
|
||||
type sendMsgFunc = func(ctx context.Context, msg *dns.Msg) (*dns.Msg, error)
|
||||
|
||||
type customDNSResult struct {
|
||||
msg *dns.Msg
|
||||
err error
|
||||
}
|
||||
|
||||
type CustomClient struct {
|
||||
server string
|
||||
sendMsgFn sendMsgFunc
|
||||
}
|
||||
|
||||
func (c *CustomClient) Resolve(ctx context.Context, host string) ([]net.IPAddr, error) {
|
||||
queryTypes := []uint16{dns.TypeAAAA, dns.TypeA}
|
||||
resultCh := c.makeLookups(ctx, host, queryTypes)
|
||||
|
||||
addrs, err := c.processResults(ctx, resultCh)
|
||||
return addrs, err
|
||||
}
|
||||
|
||||
func (c *CustomClient) makeLookups(ctx context.Context, host string, queryTypes []uint16) <-chan *customDNSResult {
|
||||
var wg sync.WaitGroup
|
||||
resCh := make(chan *customDNSResult)
|
||||
|
||||
lookup := func(qType uint16) {
|
||||
defer wg.Done()
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return
|
||||
case resCh <- c.makeLookup(ctx, host, qType):
|
||||
}
|
||||
}
|
||||
|
||||
return "", errors.New("no record found(doh)")
|
||||
for _, queryType := range queryTypes {
|
||||
wg.Add(1)
|
||||
go lookup(queryType)
|
||||
}
|
||||
go func() {
|
||||
wg.Wait()
|
||||
close(resCh)
|
||||
}()
|
||||
return resCh
|
||||
}
|
||||
|
||||
func (c *CustomClient) makeLookup(ctx context.Context, host string, queryType uint16) *customDNSResult {
|
||||
msg := c.newMsg(host, queryType)
|
||||
resp, err := c.sendMsg(ctx, msg)
|
||||
if err != nil {
|
||||
queryName := recordTypeIDToName(queryType)
|
||||
err = fmt.Errorf("resolving %s, query type %s: %w", host, queryName, err)
|
||||
return &customDNSResult{err: err}
|
||||
}
|
||||
return &customDNSResult{msg: resp}
|
||||
}
|
||||
|
||||
func (c *CustomClient) newMsg(host string, qType uint16) *dns.Msg {
|
||||
msg := new(dns.Msg)
|
||||
msg.SetQuestion(dns.Fqdn(host), qType)
|
||||
return msg
|
||||
}
|
||||
|
||||
func (c *CustomClient) sendMsg(ctx context.Context, msg *dns.Msg) (*dns.Msg, error) {
|
||||
resp, err := c.sendMsgFn(ctx, msg)
|
||||
return resp, err
|
||||
}
|
||||
|
||||
func (c *CustomClient) processResults(ctx context.Context, resCh <-chan *customDNSResult) ([]net.IPAddr, error) {
|
||||
var errs []error
|
||||
var addrs []net.IPAddr
|
||||
|
||||
for result := range resCh {
|
||||
if result.err != nil {
|
||||
errs = append(errs, result.err)
|
||||
continue
|
||||
}
|
||||
resultAddrs := parseAddrsFromMsg(result.msg)
|
||||
addrs = append(addrs, resultAddrs...)
|
||||
}
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return nil, errors.New("cancelled")
|
||||
default:
|
||||
if len(addrs) == 0 {
|
||||
return addrs, errors.Join(errs...)
|
||||
}
|
||||
}
|
||||
sortAddrs(addrs)
|
||||
return addrs, nil
|
||||
}
|
||||
|
||||
func (c *CustomClient) String() string {
|
||||
return fmt.Sprintf("CustomClient for %s", c.server)
|
||||
}
|
||||
|
||||
func NewCustomClient(server string) *CustomClient {
|
||||
clt := &dns.Client{}
|
||||
return &CustomClient{
|
||||
server: server,
|
||||
sendMsgFn: func(ctx context.Context, msg *dns.Msg) (*dns.Msg, error) {
|
||||
resp, _, err := clt.Exchange(msg, server)
|
||||
return resp, err
|
||||
},
|
||||
}
|
||||
}
|
||||
|
||||
func NewDoHClient(host string) *CustomClient {
|
||||
server := net.JoinHostPort(host, "443")
|
||||
clt := getDOHClient(server)
|
||||
return &CustomClient{
|
||||
server: server,
|
||||
sendMsgFn: func(ctx context.Context, msg *dns.Msg) (*dns.Msg, error) {
|
||||
return clt.dohExchange(ctx, msg)
|
||||
},
|
||||
}
|
||||
}
|
||||
|
||||
func recordTypeIDToName(id uint16) string {
|
||||
switch id {
|
||||
case 1:
|
||||
return "A"
|
||||
case 28:
|
||||
return "AAAA"
|
||||
}
|
||||
return strconv.FormatUint(uint64(id), 10)
|
||||
}
|
||||
|
||||
func parseAddrsFromMsg(msg *dns.Msg) []net.IPAddr {
|
||||
var addrs []net.IPAddr
|
||||
|
||||
for _, record := range msg.Answer {
|
||||
switch ipRecord := record.(type) {
|
||||
case *dns.A:
|
||||
addrs = append(addrs, net.IPAddr{IP: ipRecord.A})
|
||||
case *dns.AAAA:
|
||||
addrs = append(addrs, net.IPAddr{IP: ipRecord.AAAA})
|
||||
}
|
||||
}
|
||||
return addrs
|
||||
}
|
||||
|
||||
func parseAddr(addr string) (net.IP, error) {
|
||||
parsed, err := netip.ParseAddr(addr)
|
||||
if err != nil {
|
||||
return net.IP{}, fmt.Errorf("parsing %s as an IP address: %w", addr, err)
|
||||
}
|
||||
return parsed.AsSlice(), nil
|
||||
}
|
||||
|
||||
func sortAddrs(addrs []net.IPAddr) {
|
||||
addrselect.SortByRFC6724(addrs)
|
||||
}
|
||||
|
||||
@ -17,7 +17,7 @@ type Proxy struct {
|
||||
addr string
|
||||
port int
|
||||
timeout int
|
||||
resolver *dns.DnsResolver
|
||||
resolver *dns.Resolver
|
||||
windowSize int
|
||||
allowedPattern []*regexp.Regexp
|
||||
}
|
||||
@ -34,7 +34,7 @@ func New(config *util.Config) *Proxy {
|
||||
}
|
||||
|
||||
func (pxy *Proxy) Start() {
|
||||
l, err := net.ListenTCP("tcp4", &net.TCPAddr{IP: net.ParseIP(pxy.addr), Port: pxy.port})
|
||||
l, err := net.ListenTCP("tcp", &net.TCPAddr{IP: net.ParseIP(pxy.addr), Port: pxy.port})
|
||||
if err != nil {
|
||||
log.Fatal("[PROXY] error creating listener: ", err)
|
||||
os.Exit(1)
|
||||
@ -114,11 +114,6 @@ func (pxy *Proxy) patternMatches(bytes []byte) bool {
|
||||
}
|
||||
|
||||
func isLoopedRequest(ip net.IP) bool {
|
||||
// we don't handle IPv6 at all it seems
|
||||
if ip.To4() == nil {
|
||||
return false
|
||||
}
|
||||
|
||||
if ip.IsLoopback() {
|
||||
return true
|
||||
}
|
||||
@ -133,7 +128,7 @@ func isLoopedRequest(ip net.IP) bool {
|
||||
|
||||
for _, addr := range addr {
|
||||
if ipnet, ok := addr.(*net.IPNet); ok {
|
||||
if ipnet.IP.To4() != nil && ipnet.IP.To4().Equal(ip) {
|
||||
if ipnet.IP.Equal(ip) {
|
||||
return true
|
||||
}
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user