Validate TXT prefix and suffix

Signed-off-by: Ruud Kamphuis <ruudk@users.noreply.github.com>
kubernetes-sigs · Jul 14, 2020 · e5fce25 · e5fce25
1 parent 7505f29
commit e5fce25
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Showing 2 changed files with 44 additions and 1 deletion.
diff --git a/registry/txt.go b/registry/txt.go
@@ -20,6 +20,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"regexp"
 	"strings"
 	"time"
 
@@ -52,8 +53,30 @@ func NewTXTRegistry(provider provider.Provider, txtPrefix, txtSuffix, ownerID st
 		return nil, errors.New("txt-prefix and txt-suffix are mutual exclusive")
 	}
 
+	txtPrefix = strings.ToLower(txtPrefix)
+	txtSuffix = strings.ToLower(txtSuffix)
 	mapper := newaffixNameMapper(txtPrefix, txtSuffix)
 
+	if txtPrefix != "" {
+		matched, err := regexp.MatchString(`^[a-z0-9-.]+$`, txtPrefix)
+		if err != nil {
+			return nil, err
+		}
+		if !matched {
+			return nil, fmt.Errorf(`invalid TXT prefix provided, expected "[a-z0-9-.]+" got "%s"`, txtPrefix)
+		}
+	}
+
+	if txtSuffix != "" {
+		matched, err := regexp.MatchString(`^[a-z0-9-.]+$`, txtSuffix)
+		if err != nil {
+			return nil, err
+		}
+		if !matched {
+			return nil, fmt.Errorf(`invalid TXT suffix provided, expected "[a-z0-9-.]+" got "%s"`, txtSuffix)
+		}
+	}
+
 	return &TXTRegistry{
 		provider:      provider,
 		ownerID:       ownerID,
@@ -218,7 +241,7 @@ type affixNameMapper struct {
 var _ nameMapper = affixNameMapper{}
 
 func newaffixNameMapper(prefix string, suffix string) affixNameMapper {
-	return affixNameMapper{prefix: strings.ToLower(prefix), suffix: strings.ToLower(suffix)}
+	return affixNameMapper{prefix: prefix, suffix: suffix}
 }
 
 func (pr affixNameMapper) toEndpointName(txtDNSName string) string {

diff --git a/registry/txt_test.go b/registry/txt_test.go
@@ -60,6 +60,26 @@ func testTXTRegistryNew(t *testing.T) {
 	_, err = NewTXTRegistry(p, "txt", "txt", "owner", time.Hour)
 	require.Error(t, err)
 
+	_, err = NewTXTRegistry(p, "@invalid#", "", "owner", time.Hour)
+	require.Error(t, err, `invalid TXT prefix provided, expected "[a-z0-9-.]+" got "@invalid#"`)
+	_, err = NewTXTRegistry(p, "", "@invalid#", "owner", time.Hour)
+	require.Error(t, err, `invalid TXT suffix provided, expected "[a-z0-9-.]+" got "@invalid#"`)
+
+	_, err = NewTXTRegistry(p, "txt", "", "owner", time.Hour)
+	require.NoError(t, err)
+	_, err = NewTXTRegistry(p, "", "txt", "owner", time.Hour)
+	require.NoError(t, err)
+
+	_, err = NewTXTRegistry(p, "TxT", "", "owner", time.Hour)
+	require.NoError(t, err)
+	_, err = NewTXTRegistry(p, "", "TxT", "owner", time.Hour)
+	require.NoError(t, err)
+
+	r, err = NewTXTRegistry(p, "-sub-.", "", "owner", time.Hour)
+	require.NoError(t, err)
+	r, err = NewTXTRegistry(p, "", "-sub-.", "owner", time.Hour)
+	require.NoError(t, err)
+
 	_, ok := r.mapper.(affixNameMapper)
 	require.True(t, ok)
 	assert.Equal(t, "owner", r.ownerID)