Convert host names to fully qualified domain names

- Adds test cases for A records and Cnames
- Move cname conversion out of yaml into dns package

Signed-off-by: Nino Kodabande <[email protected]>

Author: Nino-K

pkg/hostagent/dns/dns.go

@@ -8,7 +8,6 @@ import (
 	"runtime"
 	"strings"
 
-	"github.com/lima-vm/lima/pkg/limayaml"
 	"github.com/miekg/dns"
 	"github.com/sirupsen/logrus"
 )
@@ -132,10 +131,11 @@ func NewHandler(opts HandlerOptions) (dns.Handler, error) {
 		hostToIP:     make(map[string]net.IP),
 	}
 	for host, address := range opts.StaticHosts {
+		cname := dns.CanonicalName(host)
 		if ip := net.ParseIP(address); ip != nil {
-			h.hostToIP[host] = ip
+			h.hostToIP[cname] = ip
 		} else {
-			h.cnameToHost[host] = limayaml.Cname(address)
+			h.cnameToHost[cname] = dns.CanonicalName(address)
 		}
 	}
 	return h, nil

pkg/hostagent/dns/dns_test.go

@@ -47,7 +47,10 @@ func TestDNSRecords(t *testing.T) {
 	options := HandlerOptions{
 		IPv6: true,
 		StaticHosts: map[string]string{
-			"MY.Host": "host.lima.internal",
+			"MY.DOMAIN.COM":      "192.168.0.23",
+			"host.lima.internal": "10.10.0.34",
+			"my.host":            "host.lima.internal",
+			"default":            "my.domain.com",
 		},
 	}
 
@@ -81,6 +84,40 @@ func TestDNSRecords(t *testing.T) {
 			assert.Assert(t, regexMatch(dnsResult.String(), tc.expectedTXTRecord))
 		}
 	})
+
+	t.Run("test A records", func(t *testing.T) {
+		tests := []struct {
+			testDomain      string
+			expectedARecord string
+		}{
+			{testDomain: "my.domain.com", expectedARecord: `my.domain.com.\s+5\s+IN\s+A\s+192.168.0.23`},
+			{testDomain: "host.lima.internal", expectedARecord: `host.lima.internal.\s+5\s+IN\s+A\s+10.10.0.34`},
+		}
+
+		for _, tc := range tests {
+			req := new(dns.Msg)
+			req.SetQuestion(dns.Fqdn(tc.testDomain), dns.TypeA)
+			h.ServeDNS(w, req)
+			assert.Assert(t, regexMatch(dnsResult.String(), tc.expectedARecord))
+		}
+	})
+
+	t.Run("test CNAME records", func(t *testing.T) {
+		tests := []struct {
+			testDomain    string
+			expectedCNAME string
+		}{
+			{testDomain: "my.host", expectedCNAME: `my.host.\s+5\s+IN\s+CNAME\s+host.lima.internal.`},
+			{testDomain: "default", expectedCNAME: `default.\s+5\s+IN\s+CNAME\s+my.domain.com.`},
+		}
+
+		for _, tc := range tests {
+			req := new(dns.Msg)
+			req.SetQuestion(dns.Fqdn(tc.testDomain), dns.TypeCNAME)
+			h.ServeDNS(w, req)
+			assert.Assert(t, regexMatch(dnsResult.String(), tc.expectedCNAME))
+		}
+	})
 }
 
 type TestResponseWriter struct {

pkg/hostagent/hostagent.go

@@ -307,8 +307,8 @@ func (a *HostAgent) Run(ctx context.Context) error {
 
 	if *a.y.HostResolver.Enabled {
 		hosts := a.y.HostResolver.Hosts
-		hosts["host.lima.internal."] = qemuconst.SlirpGateway
-		hosts[fmt.Sprintf("lima-%s.", a.instName)] = qemuconst.SlirpIPAddress
+		hosts["host.lima.internal"] = qemuconst.SlirpGateway
+		hosts[fmt.Sprintf("lima-%s", a.instName)] = qemuconst.SlirpIPAddress
 		srvOpts := dns.ServerOptions{
 			UDPPort: a.udpDNSLocalPort,
 			TCPPort: a.tcpDNSLocalPort,

pkg/limayaml/defaults.go

@@ -9,7 +9,6 @@ import (
 	"path/filepath"
 	"runtime"
 	"strconv"
-	"strings"
 	"text/template"
 
 	"github.com/lima-vm/lima/pkg/guestagent/api"
@@ -233,13 +232,13 @@ func FillDefault(y, d, o *LimaYAML, filePath string) {
 	hosts := make(map[string]string)
 	// Values can be either names or IP addresses. Name values are canonicalized in the hostResolver.
 	for k, v := range d.HostResolver.Hosts {
-		hosts[Cname(k)] = v
+		hosts[k] = v
 	}
 	for k, v := range y.HostResolver.Hosts {
-		hosts[Cname(k)] = v
+		hosts[k] = v
 	}
 	for k, v := range o.HostResolver.Hosts {
-		hosts[Cname(k)] = v
+		hosts[k] = v
 	}
 	y.HostResolver.Hosts = hosts
 
@@ -667,14 +666,6 @@ func IsNativeArch(arch Arch) bool {
 	return nativeX8664 || nativeAARCH64 || nativeRISCV64
 }
 
-func Cname(host string) string {
-	host = strings.ToLower(host)
-	if !strings.HasSuffix(host, ".") {
-		host += "."
-	}
-	return host
-}
-
 func unique(s []string) []string {
 	keys := make(map[string]bool)
 	list := []string{}

pkg/limayaml/defaults_test.go

@@ -149,7 +149,7 @@ func TestFillDefault(t *testing.T) {
 
 	expect := builtin
 	expect.HostResolver.Hosts = map[string]string{
-		"my.host.": "host.lima.internal",
+		"MY.Host": "host.lima.internal",
 	}
 
 	expect.Mounts = y.Mounts
@@ -319,7 +319,7 @@ func TestFillDefault(t *testing.T) {
 	expect.Mounts[0].NineP.Msize = pointer.String(Default9pMsize)
 	expect.Mounts[0].NineP.Cache = pointer.String(Default9pCacheForRO)
 	expect.HostResolver.Hosts = map[string]string{
-		"default.": d.HostResolver.Hosts["default"],
+		"default": d.HostResolver.Hosts["default"],
 	}
 	expect.MountType = pointer.String(REVSSHFS)
 	expect.CACertificates.RemoveDefaults = pointer.Bool(true)
@@ -348,7 +348,7 @@ func TestFillDefault(t *testing.T) {
 	expect.Mounts = append(d.Mounts, y.Mounts...)
 	expect.Networks = append(d.Networks, y.Networks...)
 
-	expect.HostResolver.Hosts["default."] = d.HostResolver.Hosts["default"]
+	expect.HostResolver.Hosts["default"] = d.HostResolver.Hosts["default"]
 
 	// d.DNS will be ignored, and not appended to y.DNS
 
@@ -474,8 +474,8 @@ func TestFillDefault(t *testing.T) {
 	expect.PortForwards = append(append(o.PortForwards, y.PortForwards...), d.PortForwards...)
 	expect.Containerd.Archives = append(append(o.Containerd.Archives, y.Containerd.Archives...), d.Containerd.Archives...)
 
-	expect.HostResolver.Hosts["default."] = d.HostResolver.Hosts["default"]
-	expect.HostResolver.Hosts["my.host."] = d.HostResolver.Hosts["host.lima.internal"]
+	expect.HostResolver.Hosts["default"] = d.HostResolver.Hosts["default"]
+	expect.HostResolver.Hosts["MY.Host"] = d.HostResolver.Hosts["host.lima.internal"]
 
 	// o.Mounts just makes d.Mounts[0] writable because the Location matches
 	expect.Mounts = append(d.Mounts, y.Mounts...)