From e5a3d3c5890f0891052217c6365c2bb5c8959708 Mon Sep 17 00:00:00 2001
From: Johan Siebens <johan.siebens@gmail.com>
Date: Wed, 28 Sep 2022 11:50:31 +0200
Subject: [PATCH] fix: sanitize tailnet name properly

---
 internal/domain/tailnet.go        | 20 ++++++++++++++++++++
 internal/domain/tailnet_test.go   | 15 +++++++++++++++
 internal/handlers/poll_net_map.go |  5 ++---
 internal/mapping/mapping.go       |  5 ++---
 internal/service/dns.go           |  3 +--
 5 files changed, 40 insertions(+), 8 deletions(-)
 create mode 100644 internal/domain/tailnet_test.go

diff --git a/internal/domain/tailnet.go b/internal/domain/tailnet.go
index 1885342..0c4bae6 100644
--- a/internal/domain/tailnet.go
+++ b/internal/domain/tailnet.go
@@ -5,6 +5,9 @@ import (
 	"errors"
 	"github.com/jsiebens/ionscale/internal/util"
 	"gorm.io/gorm"
+	"net/mail"
+	"strings"
+	"tailscale.com/util/dnsname"
 )
 
 type Tailnet struct {
@@ -15,6 +18,23 @@ type Tailnet struct {
 	ACLPolicy ACLPolicy
 }
 
+func SanitizeTailnetName(name string) string {
+	name = strings.ToLower(name)
+
+	a, err := mail.ParseAddress(name)
+	if err == nil && a.Address == name {
+		s := strings.Split(name, "@")
+		return strings.Join([]string{dnsname.SanitizeLabel(s[0]), s[1]}, ".")
+	}
+
+	labels := strings.Split(name, ".")
+	for i, s := range labels {
+		labels[i] = dnsname.SanitizeLabel(s)
+	}
+
+	return strings.Join(labels, ".")
+}
+
 func (r *repository) SaveTailnet(ctx context.Context, tailnet *Tailnet) error {
 	tx := r.withContext(ctx).Save(tailnet)
 
diff --git a/internal/domain/tailnet_test.go b/internal/domain/tailnet_test.go
new file mode 100644
index 0000000..8bbb630
--- /dev/null
+++ b/internal/domain/tailnet_test.go
@@ -0,0 +1,15 @@
+package domain
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestSanitizeTailnetName(t *testing.T) {
+	assert.Equal(t, "john.example.com", SanitizeTailnetName("john@example.com"))
+	assert.Equal(t, "john.example.com", SanitizeTailnetName("john@examPle.Com"))
+	assert.Equal(t, "john-doe.example.com", SanitizeTailnetName("john.doe@example.com"))
+	assert.Equal(t, "johns-network", SanitizeTailnetName("John's Network"))
+	assert.Equal(t, "example.com", SanitizeTailnetName("example.com"))
+	assert.Equal(t, "johns-example.com", SanitizeTailnetName("John's example.com"))
+}
diff --git a/internal/handlers/poll_net_map.go b/internal/handlers/poll_net_map.go
index 7c0c827..7cbd230 100644
--- a/internal/handlers/poll_net_map.go
+++ b/internal/handlers/poll_net_map.go
@@ -10,7 +10,6 @@ import (
 	"github.com/labstack/echo/v4"
 	"net/http"
 	"tailscale.com/tailcfg"
-	"tailscale.com/util/dnsname"
 	"time"
 )
 
@@ -286,7 +285,7 @@ func (h *PollNetMapHandler) createMapResponse(m *domain.Machine, binder bind.Bin
 			DNSConfig:    mapping.ToDNSConfig(&m.Tailnet, &dnsConfig),
 			PacketFilter: rules,
 			DERPMap:      derpMap,
-			Domain:       dnsname.SanitizeHostname(m.Tailnet.Name),
+			Domain:       domain.SanitizeTailnetName(m.Tailnet.Name),
 			Peers:        changedPeers,
 			UserProfiles: users,
 			ControlTime:  &controlTime,
@@ -300,7 +299,7 @@ func (h *PollNetMapHandler) createMapResponse(m *domain.Machine, binder bind.Bin
 			DNSConfig:    mapping.ToDNSConfig(&m.Tailnet, &dnsConfig),
 			PacketFilter: rules,
 			DERPMap:      derpMap,
-			Domain:       dnsname.SanitizeHostname(m.Tailnet.Name),
+			Domain:       domain.SanitizeTailnetName(m.Tailnet.Name),
 			PeersChanged: changedPeers,
 			PeersRemoved: removedPeers,
 			UserProfiles: users,
diff --git a/internal/mapping/mapping.go b/internal/mapping/mapping.go
index 6ce4ffd..042d77d 100644
--- a/internal/mapping/mapping.go
+++ b/internal/mapping/mapping.go
@@ -11,7 +11,6 @@ import (
 	"tailscale.com/tailcfg"
 	"tailscale.com/types/dnstype"
 	"tailscale.com/types/key"
-	"tailscale.com/util/dnsname"
 	"time"
 )
 
@@ -29,7 +28,7 @@ func CopyViaJson[F any, T any](f F, t T) error {
 }
 
 func ToDNSConfig(tailnet *domain.Tailnet, c *domain.DNSConfig) *tailcfg.DNSConfig {
-	tailnetDomain := dnsname.SanitizeHostname(tailnet.Name)
+	tailnetDomain := domain.SanitizeTailnetName(tailnet.Name)
 	resolvers := []*dnstype.Resolver{}
 	for _, r := range c.Nameservers {
 		resolver := &dnstype.Resolver{
@@ -131,7 +130,7 @@ func ToNode(m *domain.Machine) (*tailcfg.Node, *tailcfg.UserProfile, error) {
 		name = fmt.Sprintf("%s-%d", m.Name, m.NameIdx)
 	}
 
-	sanitizedTailnetName := dnsname.SanitizeHostname(m.Tailnet.Name)
+	sanitizedTailnetName := domain.SanitizeTailnetName(m.Tailnet.Name)
 
 	hostInfo := tailcfg.Hostinfo{
 		OS:       hostinfo.OS,
diff --git a/internal/service/dns.go b/internal/service/dns.go
index a36e4f0..0b430d4 100644
--- a/internal/service/dns.go
+++ b/internal/service/dns.go
@@ -9,7 +9,6 @@ import (
 	"github.com/jsiebens/ionscale/internal/config"
 	"github.com/jsiebens/ionscale/internal/domain"
 	api "github.com/jsiebens/ionscale/pkg/gen/ionscale/v1"
-	"tailscale.com/util/dnsname"
 )
 
 func (s *Service) GetDNSConfig(ctx context.Context, req *connect.Request[api.GetDNSConfigRequest]) (*connect.Response[api.GetDNSConfigResponse], error) {
@@ -27,7 +26,7 @@ func (s *Service) GetDNSConfig(ctx context.Context, req *connect.Request[api.Get
 	}
 
 	dnsConfig := tailnet.DNSConfig
-	tailnetDomain := dnsname.SanitizeHostname(tailnet.Name)
+	tailnetDomain := domain.SanitizeTailnetName(tailnet.Name)
 
 	resp := &api.GetDNSConfigResponse{
 		Config: &api.DNSConfig{