Pull request 386: 430-fix-system-hosts-file-path

Closes #430. Squashed commit of the following: commit 9f9870f Author: Stanislav Chzhen <[email protected]> Date: Fri Dec 27 17:16:17 2024 +0300 handler: imp docs commit f80639a Author: Stanislav Chzhen <[email protected]> Date: Fri Dec 27 16:49:41 2024 +0300 handler: imp tests commit ef2dd46 Author: Stanislav Chzhen <[email protected]> Date: Fri Dec 27 16:37:59 2024 +0300 handler: imp code commit 0f4241d Author: Stanislav Chzhen <[email protected]> Date: Fri Dec 27 16:00:08 2024 +0300 handler: fix ptr commit 64cc591 Author: Stanislav Chzhen <[email protected]> Date: Fri Dec 27 14:22:15 2024 +0300 all: imp code commit d16be8a Author: Stanislav Chzhen <[email protected]> Date: Thu Dec 26 22:01:30 2024 +0300 all: fix system hosts file path
AdguardTeam · Dec 27, 2024 · 712d38b · 712d38b
1 parent ed4be08
commit 712d38b
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Showing 7 changed files with 67 additions and 15 deletions.
diff --git a/internal/cmd/proxy.go b/internal/cmd/proxy.go
@@ -18,7 +18,6 @@ import (
 	"github.com/AdguardTeam/dnsproxy/proxy"
 	"github.com/AdguardTeam/dnsproxy/upstream"
 	"github.com/AdguardTeam/golibs/errors"
-	"github.com/AdguardTeam/golibs/hostsfile"
 	"github.com/AdguardTeam/golibs/logutil/slogutil"
 	"github.com/AdguardTeam/golibs/netutil"
 	"github.com/AdguardTeam/golibs/osutil"
@@ -518,7 +517,7 @@ func (conf *configuration) hostsFiles(ctx context.Context, l *slog.Logger) (path
 		return conf.HostsFiles, nil
 	}
 
-	paths, err = hostsfile.DefaultHostsPaths()
+	paths, err = proxynetutil.DefaultHostsPaths()
 	if err != nil {
 		return nil, fmt.Errorf("getting default hosts files: %w", err)
 	}

diff --git a/internal/handler/constructor.go b/internal/handler/constructor.go
@@ -17,8 +17,9 @@ type messageConstructor interface {
 	NewCompressedResponse(req *dns.Msg, code int) (resp *dns.Msg)
 
 	// NewPTRAnswer creates a new resource record for PTR response with the
-	// given FQDN and PTR domain.
-	NewPTRAnswer(fqdn, ptrDomain string) (ans *dns.PTR)
+	// given FQDN and PTR domain.  Arguments must be fully qualified domain
+	// names.
+	NewPTRAnswer(fqdn, ptrFQDN string) (ans *dns.PTR)
 
 	// NewIPResponse creates a new A/AAAA response message for req with the
 	// given IP addresses.  All IP addresses must be of the same family.
@@ -48,10 +49,10 @@ func (defaultConstructor) NewCompressedResponse(req *dns.Msg, code int) (resp *d
 
 // NewPTRAnswer implements the [messageConstructor] interface for
 // [defaultConstructor].
-func (defaultConstructor) NewPTRAnswer(fqdn, ptrDomain string) (ans *dns.PTR) {
+func (defaultConstructor) NewPTRAnswer(fqdn, ptrFQDN string) (ans *dns.PTR) {
 	return &dns.PTR{
 		Hdr: hdr(fqdn, dns.TypePTR),
-		Ptr: ptrDomain,
+		Ptr: dns.Fqdn(ptrFQDN),
 	}
 }
 

diff --git a/internal/handler/default_internal_test.go b/internal/handler/default_internal_test.go
@@ -98,8 +98,8 @@ func TestDefault_resolveFromHosts(t *testing.T) {
 	})
 
 	const (
-		domainV4 = "ipv4.domain.example"
-		domainV6 = "ipv6.domain.example"
+		fqdnV4 = "ipv4.domain.example."
+		fqdnV6 = "ipv6.domain.example."
 	)
 
 	var (
@@ -118,26 +118,26 @@ func TestDefault_resolveFromHosts(t *testing.T) {
 	}{{
 		wantAns: &dns.A{
 			Hdr: dns.RR_Header{
-				Name:   domainV4,
+				Name:   fqdnV4,
 				Rrtype: dns.TypeA,
 				Class:  dns.ClassINET,
 				Ttl:    10,
 			},
 			A: addrV4.AsSlice(),
 		},
-		req:  (&dns.Msg{}).SetQuestion(domainV4, dns.TypeA),
+		req:  (&dns.Msg{}).SetQuestion(fqdnV4, dns.TypeA),
 		name: "success_a",
 	}, {
 		wantAns: &dns.AAAA{
 			Hdr: dns.RR_Header{
-				Name:   domainV6,
+				Name:   fqdnV6,
 				Rrtype: dns.TypeAAAA,
 				Class:  dns.ClassINET,
 				Ttl:    10,
 			},
 			AAAA: addrV6.AsSlice(),
 		},
-		req:  (&dns.Msg{}).SetQuestion(domainV6, dns.TypeAAAA),
+		req:  (&dns.Msg{}).SetQuestion(fqdnV6, dns.TypeAAAA),
 		name: "success_aaaa",
 	}, {
 		wantAns: &dns.PTR{
@@ -147,7 +147,7 @@ func TestDefault_resolveFromHosts(t *testing.T) {
 				Class:  dns.ClassINET,
 				Ttl:    10,
 			},
-			Ptr: domainV4,
+			Ptr: fqdnV4,
 		},
 		req:  (&dns.Msg{}).SetQuestion(reversedV4, dns.TypePTR),
 		name: "success_ptr_v4",
@@ -159,7 +159,7 @@ func TestDefault_resolveFromHosts(t *testing.T) {
 				Class:  dns.ClassINET,
 				Ttl:    10,
 			},
-			Ptr: domainV6,
+			Ptr: fqdnV6,
 		},
 		req:  (&dns.Msg{}).SetQuestion(reversedV6, dns.TypePTR),
 		name: "success_ptr_v6",

diff --git a/internal/handler/hosts.go b/internal/handler/hosts.go
@@ -117,7 +117,7 @@ func (h *Default) resolveFromHosts(ctx context.Context, req *dns.Msg) (resp *dns
 		resp = h.messages.NewCompressedResponse(req, dns.RcodeSuccess)
 		name = req.Question[0].Name
 		for _, ptr := range ptrs {
-			resp.Answer = append(resp.Answer, h.messages.NewPTRAnswer(name, ptr))
+			resp.Answer = append(resp.Answer, h.messages.NewPTRAnswer(name, dns.Fqdn(ptr)))
 		}
 	default:
 		h.logger.DebugContext(ctx, "no hosts records found", "name", name, "qtype", q.Qtype)

diff --git a/internal/netutil/paths.go b/internal/netutil/paths.go
@@ -0,0 +1,9 @@
+package netutil
+
+// DefaultHostsPaths returns the slice of default paths to system hosts files.
+//
+// TODO(s.chzhen):  Since [fs.FS] is no longer needed, update the
+// [hostsfile.DefaultHostsPaths] from golibs.
+func DefaultHostsPaths() (paths []string, err error) {
+	return defaultHostsPaths()
+}
diff --git a/internal/netutil/paths_unix.go b/internal/netutil/paths_unix.go
@@ -0,0 +1,21 @@
+//go:build unix
+
+package netutil
+
+import "github.com/AdguardTeam/golibs/hostsfile"
+
+// defaultHostsPaths returns default paths to hosts files for UNIX.
+func defaultHostsPaths() (paths []string, err error) {
+	paths, err = hostsfile.DefaultHostsPaths()
+	if err != nil {
+		// Should not happen because error is always nil.
+		panic(err)
+	}
+
+	res := make([]string, 0, len(paths))
+	for _, p := range paths {
+		res = append(res, "/"+p)
+	}
+
+	return res, nil
+}
diff --git a/internal/netutil/paths_windows.go b/internal/netutil/paths_windows.go
@@ -0,0 +1,22 @@
+//go:build windows
+
+package netutil
+
+import (
+	"fmt"
+	"path"
+
+	"golang.org/x/sys/windows"
+)
+
+// defaultHostsPaths returns default paths to hosts files for Windows.
+func defaultHostsPaths() (paths []string, err error) {
+	sysDir, err := windows.GetSystemDirectory()
+	if err != nil {
+		return []string{}, fmt.Errorf("getting system directory: %w", err)
+	}
+
+	p := path.Join(sysDir, "drivers", "etc", "hosts")
+
+	return []string{p}, nil
+}