update to latest adns, synced with Go's net

go.mod

@@ -3,7 +3,7 @@ module github.com/mjl-/mox
 go 1.21
 
 require (
-	github.com/mjl-/adns v0.0.0-20231109160910-82839fe3e6ae
+	github.com/mjl-/adns v0.0.0-20240308133139-6bfb89c3f854
 	github.com/mjl-/autocert v0.0.0-20231214125928-31b7400acb05
 	github.com/mjl-/bstore v0.0.4
 	github.com/mjl-/sconf v0.0.5

go.sum

@@ -24,8 +24,8 @@ github.com/kr/logfmt v0.0.0-20140226030751-b84e30acd515/go.mod h1:+0opPa2QZZtGFB
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
 github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0 h1:jWpvCLoY8Z/e3VKvlsiIGKtc+UG6U5vzxaoagmhXfyg=
 github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0/go.mod h1:QUyp042oQthUoa9bqDv0ER0wrtXnBruoNd7aNjkbP+k=
-github.com/mjl-/adns v0.0.0-20231109160910-82839fe3e6ae h1:P/kTaQbDFSbmDK+RVjwu7mPyr6a6XyHqHu1PlRMEbAU=
+github.com/mjl-/adns v0.0.0-20240308133139-6bfb89c3f854 h1:BeYqeRkulstKKKCdzk7IOYNeuJPhqmLnaMhu69GxQUs=
-github.com/mjl-/adns v0.0.0-20231109160910-82839fe3e6ae/go.mod h1:v47qUMJnipnmDTRGaHwpCwzE6oypa5K33mUvBfzZBn8=
+github.com/mjl-/adns v0.0.0-20240308133139-6bfb89c3f854/go.mod h1:v47qUMJnipnmDTRGaHwpCwzE6oypa5K33mUvBfzZBn8=
 github.com/mjl-/autocert v0.0.0-20231214125928-31b7400acb05 h1:s6ay4bh4tmpPLdxjyeWG45mcwHfEluBMuGPkqxHWUJ4=
 github.com/mjl-/autocert v0.0.0-20231214125928-31b7400acb05/go.mod h1:taMFU86abMxKLPV4Bynhv8enbYmS67b8LG80qZv2Qus=
 github.com/mjl-/bstore v0.0.4 h1:q+R1oAr8+E9yf9q+zxkVjQ18VFqD/E9KmGVoe4FIOBA=

vendor/github.com/mjl-/adns/conf.go

@@ -157,7 +157,7 @@ func initConfVal() {
 	}
 }
 
-// goosPreferCgo reports whether the GOOS value passed in prefers
+// goosPrefersCgo reports whether the GOOS value passed in prefers
 // the cgo resolver.
 func goosPrefersCgo() bool {
 	switch runtime.GOOS {
@@ -225,16 +225,7 @@ func (c *conf) lookupOrder(r *Resolver, hostname string) (ret hostLookupOrder, d
 		// Go resolver was explicitly requested
 		// or cgo resolver is not available.
 		// Figure out the order below.
-		switch c.goos {
+		fallbackOrder = hostLookupFilesDNS
-		case "windows":
-			// TODO(bradfitz): implement files-based
-			// lookup on Windows too? I guess /etc/hosts
-			// kinda exists on Windows. But for now, only
-			// do DNS.
-			fallbackOrder = hostLookupDNS
-		default:
-			fallbackOrder = hostLookupFilesDNS
-		}
 		canUseCgo = false
 	} else if c.netCgo {
 		// Cgo resolver was explicitly requested.

vendor/github.com/mjl-/adns/dial.go

@@ -7,10 +7,12 @@ package adns
 import (
 	"context"
 	"net"
+
+	"github.com/mjl-/adns/internal/bytealg"
 )
 
 func parseNetwork(ctx context.Context, network string, needsProto bool) (afnet string, proto int, err error) {
-	i := last(network, ':')
+	i := bytealg.LastIndexByteString(network, ':')
 	if i < 0 { // no colon
 		switch network {
 		case "tcp", "tcp4", "tcp6":

vendor/github.com/mjl-/adns/dnsclient_unix.go

@@ -29,6 +29,7 @@ import (
 
 	"golang.org/x/net/dns/dnsmessage"
 
+	"github.com/mjl-/adns/internal/bytealg"
 	"github.com/mjl-/adns/internal/itoa"
 )
 
@@ -205,7 +206,14 @@ func (r *Resolver) exchange(ctx context.Context, server string, q dnsmessage.Que
 		if err := p.SkipQuestion(); err != dnsmessage.ErrSectionDone {
 			return dnsmessage.Parser{}, dnsmessage.Header{}, errInvalidDNSResponse
 		}
-		if h.Truncated { // see RFC 5966
+		// RFC 5966 indicates that when a client receives a UDP response with
+		// the TC flag set, it should take the TC flag as an indication that it
+		// should retry over TCP instead.
+		// The case when the TC flag is set in a TCP response is not well specified,
+		// so this implements the glibc resolver behavior, returning the existing
+		// dns response instead of returning a "errNoAnswerFromDNSServer" error.
+		// See go.dev/issue/64896
+		if h.Truncated && network == "udp" {
 			continue
 		}
 		return p, h, nil
@@ -215,7 +223,9 @@ func (r *Resolver) exchange(ctx context.Context, server string, q dnsmessage.Que
 
 // checkHeader performs basic sanity checks on the header.
 func checkHeader(p *dnsmessage.Parser, h dnsmessage.Header) error {
-	if h.RCode == dnsmessage.RCodeNameError {
+	rcode, hasAdd := extractExtendedRCode(*p, h)
+
+	if rcode == dnsmessage.RCodeNameError {
 		return errNoSuchHost
 	}
 
@@ -226,17 +236,17 @@ func checkHeader(p *dnsmessage.Parser, h dnsmessage.Header) error {
 
 	// libresolv continues to the next server when it receives
 	// an invalid referral response. See golang.org/issue/15434.
-	if h.RCode == dnsmessage.RCodeSuccess && !h.Authoritative && !h.RecursionAvailable && err == dnsmessage.ErrSectionDone {
+	if rcode == dnsmessage.RCodeSuccess && !h.Authoritative && !h.RecursionAvailable && err == dnsmessage.ErrSectionDone && !hasAdd {
 		return errLameReferral
 	}
 
-	if h.RCode != dnsmessage.RCodeSuccess && h.RCode != dnsmessage.RCodeNameError {
+	if rcode != dnsmessage.RCodeSuccess && h.RCode != dnsmessage.RCodeNameError {
 		// None of the error codes make sense
 		// for the query we sent. If we didn't get
 		// a name error and we didn't get success,
 		// the server is behaving incorrectly or
 		// having temporary trouble.
-		if h.RCode == dnsmessage.RCodeServerFailure {
+		if rcode == dnsmessage.RCodeServerFailure {
 			// Look for Extended DNS Error (EDE), RFC 8914.
 
 			if p.SkipAllAnswers() != nil || p.SkipAllAuthorities() != nil {
@@ -302,6 +312,26 @@ func skipToAnswer(p *dnsmessage.Parser, qtype dnsmessage.Type) error {
 	}
 }
 
+// extractExtendedRCode extracts the extended RCode from the OPT resource (EDNS(0))
+// If an OPT record is not found, the RCode from the hdr is returned.
+// Another return value indicates whether an additional resource was found.
+func extractExtendedRCode(p dnsmessage.Parser, hdr dnsmessage.Header) (dnsmessage.RCode, bool) {
+	p.SkipAllAnswers()
+	p.SkipAllAuthorities()
+	hasAdd := false
+	for {
+		ahdr, err := p.AdditionalHeader()
+		if err != nil {
+			return hdr.RCode, hasAdd
+		}
+		hasAdd = true
+		if ahdr.Type == dnsmessage.TypeOPT {
+			return ahdr.ExtendedRCode(hdr.RCode), hasAdd
+		}
+		p.SkipAdditional()
+	}
+}
+
 // Do a lookup for a single name, which must be rooted
 // (otherwise answer will not find the answers).
 func (r *Resolver) tryOneName(ctx context.Context, cfg *dnsConfig, name string, qtype dnsmessage.Type) (dnsmessage.Parser, string, Result, error) {
@@ -542,10 +572,6 @@ func avoidDNS(name string) bool {
 
 // nameList returns a list of names for sequential DNS queries.
 func (conf *dnsConfig) nameList(name string) []string {
-	if avoidDNS(name) {
-		return nil
-	}
-
 	// Check name length (see isDomainName).
 	l := len(name)
 	rooted := l > 0 && name[l-1] == '.'
@@ -555,27 +581,31 @@ func (conf *dnsConfig) nameList(name string) []string {
 
 	// If name is rooted (trailing dot), try only that name.
 	if rooted {
+		if avoidDNS(name) {
+			return nil
+		}
 		return []string{name}
 	}
 
-	hasNdots := count(name, '.') >= conf.ndots
+	hasNdots := bytealg.CountString(name, '.') >= conf.ndots
 	name += "."
 	l++
 
 	// Build list of search choices.
 	names := make([]string, 0, 1+len(conf.search))
 	// If name has enough dots, try unsuffixed first.
-	if hasNdots {
+	if hasNdots && !avoidDNS(name) {
 		names = append(names, name)
 	}
 	// Try suffixes that are not too long (see isDomainName).
 	for _, suffix := range conf.search {
-		if l+len(suffix) <= 254 {
+		fqdn := name + suffix
-			names = append(names, name+suffix)
+		if !avoidDNS(fqdn) && len(fqdn) <= 254 {
+			names = append(names, fqdn)
 		}
 	}
 	// Try unsuffixed, if not tried first above.
-	if !hasNdots {
+	if !hasNdots && !avoidDNS(name) {
 		names = append(names, name)
 	}
 	return names
@@ -767,7 +797,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
 				h, err := result0.p.AnswerHeader()
 				if err != nil && err != dnsmessage.ErrSectionDone {
 					lastErr = &DNSError{
-						Err:    "cannot marshal DNS message",
+						Err:    errCannotUnmarshalDNSMessage.Error(),
 						Name:   name,
 						Server: result0.server,
 					}
@@ -780,7 +810,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
 					a, err := result0.p.AResource()
 					if err != nil {
 						lastErr = &DNSError{
-							Err:    "cannot marshal DNS message",
+							Err:    errCannotUnmarshalDNSMessage.Error(),
 							Name:   name,
 							Server: result0.server,
 						}
@@ -795,7 +825,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
 					aaaa, err := result0.p.AAAAResource()
 					if err != nil {
 						lastErr = &DNSError{
-							Err:    "cannot marshal DNS message",
+							Err:    errCannotUnmarshalDNSMessage.Error(),
 							Name:   name,
 							Server: result0.server,
 						}
@@ -810,7 +840,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
 					c, err := result0.p.CNAMEResource()
 					if err != nil {
 						lastErr = &DNSError{
-							Err:    "cannot marshal DNS message",
+							Err:    errCannotUnmarshalDNSMessage.Error(),
 							Name:   name,
 							Server: result0.server,
 						}
@@ -823,7 +853,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
 				default:
 					if err := result0.p.SkipAnswer(); err != nil {
 						lastErr = &DNSError{
-							Err:    "cannot marshal DNS message",
+							Err:    errCannotUnmarshalDNSMessage.Error(),
 							Name:   name,
 							Server: result0.server,
 						}
@@ -915,7 +945,7 @@ func (r *Resolver) goLookupPTR(ctx context.Context, addr string, order hostLooku
 		}
 		if err != nil {
 			return nil, result, &DNSError{
-				Err:    "cannot marshal DNS message",
+				Err:    errCannotUnmarshalDNSMessage.Error(),
 				Name:   addr,
 				Server: server,
 			}
@@ -924,7 +954,7 @@ func (r *Resolver) goLookupPTR(ctx context.Context, addr string, order hostLooku
 			err := p.SkipAnswer()
 			if err != nil {
 				return nil, result, &DNSError{
-					Err:    "cannot marshal DNS message",
+					Err:    errCannotUnmarshalDNSMessage.Error(),
 					Name:   addr,
 					Server: server,
 				}
@@ -934,7 +964,7 @@ func (r *Resolver) goLookupPTR(ctx context.Context, addr string, order hostLooku
 		ptr, err := p.PTRResource()
 		if err != nil {
 			return nil, result, &DNSError{
-				Err:    "cannot marshal DNS message",
+				Err:    errCannotUnmarshalDNSMessage.Error(),
 				Name:   addr,
 				Server: server,
 			}

vendor/github.com/mjl-/adns/hook.go

@@ -10,8 +10,7 @@ import (
 )
 
 var (
-	testHookHostsPath = "/etc/hosts"
+	testHookLookupIP = func(
-	testHookLookupIP  = func(
 		ctx context.Context,
 		fn func(context.Context, string, string) ([]net.IPAddr, Result, error),
 		network string,

vendor/github.com/mjl-/adns/hook_plan9.go

@@ -0,0 +1,9 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+var (
+	hostsFilePath = "/etc/hosts"
+)

vendor/github.com/mjl-/adns/hook_unix.go

@@ -0,0 +1,11 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js || wasip1
+
+package adns
+
+var (
+	hostsFilePath = "/etc/hosts"
+)

vendor/github.com/mjl-/adns/hook_windows.go

@@ -0,0 +1,18 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package adns
+
+import (
+	"golang.org/x/sys/windows"
+)
+
+func windowsGetSystemDirectory() string {
+	p, _ := windows.GetSystemDirectory()
+	return p
+}
+
+var (
+	hostsFilePath = windowsGetSystemDirectory() + "/Drivers/etc/hosts"
+)

vendor/github.com/mjl-/adns/hosts.go

@@ -52,7 +52,7 @@ var hosts struct {
 
 func readHosts() {
 	now := time.Now()
-	hp := testHookHostsPath
+	hp := hostsFilePath
 
 	if now.Before(hosts.expire) && hosts.path == hp && len(hosts.byName) > 0 {
 		return

vendor/github.com/mjl-/adns/internal/bytealg/count_generic.go

@@ -0,0 +1,25 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytealg
+
+func Count(b []byte, c byte) int {
+	n := 0
+	for _, x := range b {
+		if x == c {
+			n++
+		}
+	}
+	return n
+}
+
+func CountString(s string, c byte) int {
+	n := 0
+	for i := 0; i < len(s); i++ {
+		if s[i] == c {
+			n++
+		}
+	}
+	return n
+}

vendor/github.com/mjl-/adns/internal/bytealg/lastindexbyte_generic.go

@@ -0,0 +1,23 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytealg
+
+func LastIndexByte(s []byte, c byte) int {
+	for i := len(s) - 1; i >= 0; i-- {
+		if s[i] == c {
+			return i
+		}
+	}
+	return -1
+}
+
+func LastIndexByteString(s string, c byte) int {
+	for i := len(s) - 1; i >= 0; i-- {
+		if s[i] == c {
+			return i
+		}
+	}
+	return -1
+}

vendor/github.com/mjl-/adns/ipsock.go

@@ -68,7 +68,7 @@ func SplitHostPort(hostport string) (host, port string, err error) {
 	j, k := 0, 0
 
 	// The port starts after the last colon.
-	i := last(hostport, ':')
+	i := bytealg.LastIndexByteString(hostport, ':')
 	if i < 0 {
 		return addrErr(hostport, missingPort)
 	}
@@ -115,7 +115,7 @@ func SplitHostPort(hostport string) (host, port string, err error) {
 func splitHostZone(s string) (host, zone string) {
 	// The IPv6 scoped addressing zone identifier starts after the
 	// last percent sign.
-	if i := last(s, '%'); i > 0 {
+	if i := bytealg.LastIndexByteString(s, '%'); i > 0 {
 		host, zone = s[:i], s[i+1:]
 	} else {
 		host = s

vendor/github.com/mjl-/adns/lookup.go

@@ -42,19 +42,20 @@ var services = map[string]map[string]int{
 		"domain": 53,
 	},
 	"tcp": {
-		"ftp":    21,
+		"ftp":         21,
-		"ftps":   990,
+		"ftps":        990,
-		"gopher": 70, // ʕ◔ϖ◔ʔ
+		"gopher":      70, // ʕ◔ϖ◔ʔ
-		"http":   80,
+		"http":        80,
-		"https":  443,
+		"https":       443,
-		"imap2":  143,
+		"imap2":       143,
-		"imap3":  220,
+		"imap3":       220,
-		"imaps":  993,
+		"imaps":       993,
-		"pop3":   110,
+		"pop3":        110,
-		"pop3s":  995,
+		"pop3s":       995,
-		"smtp":   25,
+		"smtp":        25,
-		"ssh":    22,
+		"submissions": 465,
-		"telnet": 23,
+		"ssh":         22,
+		"telnet":      23,
 	},
 }
 
@@ -84,12 +85,20 @@ const maxPortBufSize = len("mobility-header") + 10
 
 func lookupPortMap(network, service string) (port int, error error) {
 	switch network {
-	case "tcp4", "tcp6":
+	case "ip": // no hints
-		network = "tcp"
+		if p, err := lookupPortMapWithNetwork("tcp", "ip", service); err == nil {
-	case "udp4", "udp6":
+			return p, nil
-		network = "udp"
+		}
+		return lookupPortMapWithNetwork("udp", "ip", service)
+	case "tcp", "tcp4", "tcp6":
+		return lookupPortMapWithNetwork("tcp", "tcp", service)
+	case "udp", "udp4", "udp6":
+		return lookupPortMapWithNetwork("udp", "udp", service)
 	}
+	return 0, &DNSError{Err: "unknown network", Name: network + "/" + service}
+}
 
+func lookupPortMapWithNetwork(network, errNetwork, service string) (port int, error error) {
 	if m, ok := services[network]; ok {
 		var lowerService [maxPortBufSize]byte
 		n := copy(lowerService[:], service)
@@ -97,8 +106,9 @@ func lookupPortMap(network, service string) (port int, error error) {
 		if port, ok := m[string(lowerService[:n])]; ok && n == len(service) {
 			return port, nil
 		}
+		return 0, &DNSError{Err: "unknown port", Name: errNetwork + "/" + service, IsNotFound: true}
 	}
-	return 0, &net.AddrError{Err: "unknown port", Addr: network + "/" + service}
+	return 0, &DNSError{Err: "unknown network", Name: errNetwork + "/" + service}
 }
 
 // ipVersion returns the provided network's IP version: '4', '6' or 0
@@ -399,11 +409,13 @@ func LookupPort(network, service string) (port int, err error) {
 }
 
 // LookupPort looks up the port for the given network and service.
+//
+// The network must be one of "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6" or "ip".
 func (r *Resolver) LookupPort(ctx context.Context, network, service string) (port int, err error) {
 	port, needsLookup := parsePort(service)
 	if needsLookup {
 		switch network {
-		case "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6":
+		case "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6", "ip":
 		case "": // a hint wildcard for Go 1.0 undocumented behavior
 			network = "ip"
 		default:

vendor/github.com/mjl-/adns/net.go

@@ -79,7 +79,11 @@ type DNSError struct {
 	Server      string // server used
 	IsTimeout   bool   // if true, timed out; not all timeouts set this
 	IsTemporary bool   // if true, error is temporary; not all errors set this
-	IsNotFound  bool   // if true, host could not be found
+
+	// IsNotFound is set to true when the requested name does not
+	// contain any records of the requested type (data not found),
+	// or the name itself was not found (NXDOMAIN).
+	IsNotFound bool
 }
 
 // Unwrap returns the underlying error, which could be an ExtendedError.

vendor/github.com/mjl-/adns/parse.go

@@ -142,28 +142,6 @@ func dtoi(s string) (n int, i int, ok bool) {
 	return n, i, true
 }
 
-// Number of occurrences of b in s.
-func count(s string, b byte) int {
-	n := 0
-	for i := 0; i < len(s); i++ {
-		if s[i] == b {
-			n++
-		}
-	}
-	return n
-}
-
-// Index of rightmost occurrence of b in s.
-func last(s string, b byte) int {
-	i := len(s)
-	for i--; i >= 0; i-- {
-		if s[i] == b {
-			break
-		}
-	}
-	return i
-}
-
 // hasUpperCase tells whether the given string contains at least one upper-case.
 func hasUpperCase(s string) bool {
 	for i := range s {

vendor/modules.txt

@@ -7,7 +7,7 @@ github.com/cespare/xxhash/v2
 # github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0
 ## explicit; go 1.19
 github.com/matttproud/golang_protobuf_extensions/v2/pbutil
-# github.com/mjl-/adns v0.0.0-20231109160910-82839fe3e6ae
+# github.com/mjl-/adns v0.0.0-20240308133139-6bfb89c3f854
 ## explicit; go 1.20
 github.com/mjl-/adns
 github.com/mjl-/adns/internal/bytealg