diff --git a/internal/arpdb/arpdb.go b/internal/arpdb/arpdb.go
index ebb11011..66b1ae1e 100644
--- a/internal/arpdb/arpdb.go
+++ b/internal/arpdb/arpdb.go
@@ -77,8 +77,8 @@ func (n Neighbor) Clone() (clone Neighbor) {
 	}
 }
 
-// validatedHostname returns valid hostname.  Otherwise returns empty string and
-// logs the error if hostname is not valid.
+// validatedHostname returns h if it's a valid hostname, or an empty string
+// otherwise, logging the validation error.
 func validatedHostname(h string) (host string) {
 	err := netutil.ValidateHostname(h)
 	if err != nil {
diff --git a/internal/client/client.go b/internal/client/client.go
index 6cfcec79..6b81b9b8 100644
--- a/internal/client/client.go
+++ b/internal/client/client.go
@@ -3,3 +3,52 @@
 //
 // TODO(a.garipov): Expand.
 package client
+
+import (
+	"encoding"
+	"fmt"
+)
+
+// Source represents the source from which the information about the client has
+// been obtained.
+type Source uint8
+
+// Clients information sources.  The order determines the priority.
+const (
+	SourceNone Source = iota
+	SourceWHOIS
+	SourceARP
+	SourceRDNS
+	SourceDHCP
+	SourceHostsFile
+	SourcePersistent
+)
+
+// type check
+var _ fmt.Stringer = Source(0)
+
+// String returns a human-readable name of cs.
+func (cs Source) String() (s string) {
+	switch cs {
+	case SourceWHOIS:
+		return "WHOIS"
+	case SourceARP:
+		return "ARP"
+	case SourceRDNS:
+		return "rDNS"
+	case SourceDHCP:
+		return "DHCP"
+	case SourceHostsFile:
+		return "etc/hosts"
+	default:
+		return ""
+	}
+}
+
+// type check
+var _ encoding.TextMarshaler = Source(0)
+
+// MarshalText implements encoding.TextMarshaler for the Source.
+func (cs Source) MarshalText() (text []byte, err error) {
+	return []byte(cs.String()), nil
+}
diff --git a/internal/home/client.go b/internal/home/client.go
index c0d39dad..751bde6d 100644
--- a/internal/home/client.go
+++ b/internal/home/client.go
@@ -1,10 +1,10 @@
 package home
 
 import (
-	"encoding"
 	"fmt"
 	"time"
 
+	"github.com/AdguardTeam/AdGuardHome/internal/client"
 	"github.com/AdguardTeam/AdGuardHome/internal/filtering"
 	"github.com/AdguardTeam/AdGuardHome/internal/filtering/safesearch"
 	"github.com/AdguardTeam/AdGuardHome/internal/whois"
@@ -83,50 +83,6 @@ func (c *Client) setSafeSearch(
 	return nil
 }
 
-// clientSource represents the source from which the information about the
-// client has been obtained.
-type clientSource uint
-
-// Clients information sources.  The order determines the priority.
-const (
-	ClientSourceNone clientSource = iota
-	ClientSourceWHOIS
-	ClientSourceARP
-	ClientSourceRDNS
-	ClientSourceDHCP
-	ClientSourceHostsFile
-	ClientSourcePersistent
-)
-
-// type check
-var _ fmt.Stringer = clientSource(0)
-
-// String returns a human-readable name of cs.
-func (cs clientSource) String() (s string) {
-	switch cs {
-	case ClientSourceWHOIS:
-		return "WHOIS"
-	case ClientSourceARP:
-		return "ARP"
-	case ClientSourceRDNS:
-		return "rDNS"
-	case ClientSourceDHCP:
-		return "DHCP"
-	case ClientSourceHostsFile:
-		return "etc/hosts"
-	default:
-		return ""
-	}
-}
-
-// type check
-var _ encoding.TextMarshaler = clientSource(0)
-
-// MarshalText implements encoding.TextMarshaler for the clientSource.
-func (cs clientSource) MarshalText() (text []byte, err error) {
-	return []byte(cs.String()), nil
-}
-
 // RuntimeClient is a client information about which has been obtained using the
 // source described in the Source field.
 type RuntimeClient struct {
@@ -138,5 +94,5 @@ type RuntimeClient struct {
 
 	// Source is the source from which the information about the client has
 	// been obtained.
-	Source clientSource
+	Source client.Source
 }
diff --git a/internal/home/clients.go b/internal/home/clients.go
index 6a0ab9fd..68e0b7d1 100644
--- a/internal/home/clients.go
+++ b/internal/home/clients.go
@@ -307,15 +307,15 @@ func (clients *clientsContainer) periodicUpdate() {
 }
 
 // clientSource checks if client with this IP address already exists and returns
-// the source which updated it last.  It returns [ClientSourceNone] if the
+// the source which updated it last.  It returns [client.SourceNone] if the
 // client doesn't exist.
-func (clients *clientsContainer) clientSource(ip netip.Addr) (src clientSource) {
+func (clients *clientsContainer) clientSource(ip netip.Addr) (src client.Source) {
 	clients.lock.Lock()
 	defer clients.lock.Unlock()
 
 	_, ok := clients.findLocked(ip.String())
 	if ok {
-		return ClientSourcePersistent
+		return client.SourcePersistent
 	}
 
 	rc, ok := clients.ipToRC[ip]
@@ -323,8 +323,8 @@ func (clients *clientsContainer) clientSource(ip netip.Addr) (src clientSource)
 		src = rc.Source
 	}
 
-	if src < ClientSourceDHCP && clients.dhcp.HostByIP(ip) != "" {
-		src = ClientSourceDHCP
+	if src < client.SourceDHCP && clients.dhcp.HostByIP(ip) != "" {
+		src = client.SourceDHCP
 	}
 
 	return src
@@ -533,7 +533,7 @@ func (clients *clientsContainer) runtimeClient(ip netip.Addr) (rc *RuntimeClient
 
 // findRuntimeClient finds a runtime client by their IP.
 func (clients *clientsContainer) findRuntimeClient(ip netip.Addr) (rc *RuntimeClient, ok bool) {
-	if rc, ok = clients.runtimeClient(ip); ok && rc.Source > ClientSourceDHCP {
+	if rc, ok = clients.runtimeClient(ip); ok && rc.Source > client.SourceDHCP {
 		return rc, ok
 	}
 
@@ -544,7 +544,7 @@ func (clients *clientsContainer) findRuntimeClient(ip netip.Addr) (rc *RuntimeCl
 
 	return &RuntimeClient{
 		Host:   host,
-		Source: ClientSourceDHCP,
+		Source: client.SourceDHCP,
 		WHOIS:  &whois.Info{},
 	}, true
 }
@@ -744,7 +744,7 @@ func (clients *clientsContainer) setWHOISInfo(ip netip.Addr, wi *whois.Info) {
 		// Create a RuntimeClient implicitly so that we don't do this check
 		// again.
 		rc = &RuntimeClient{
-			Source: ClientSourceWHOIS,
+			Source: client.SourceWHOIS,
 		}
 		clients.ipToRC[ip] = rc
 
@@ -763,7 +763,7 @@ func (clients *clientsContainer) setWHOISInfo(ip netip.Addr, wi *whois.Info) {
 func (clients *clientsContainer) addHost(
 	ip netip.Addr,
 	host string,
-	src clientSource,
+	src client.Source,
 ) (ok bool) {
 	clients.lock.Lock()
 	defer clients.lock.Unlock()
@@ -786,7 +786,7 @@ func (clients *clientsContainer) UpdateAddress(ip netip.Addr, host string, info
 	defer clients.lock.Unlock()
 
 	if host != "" {
-		ok := clients.addHostLocked(ip, host, ClientSourceRDNS)
+		ok := clients.addHostLocked(ip, host, client.SourceRDNS)
 		if !ok {
 			log.Debug("clients: host for client %q already set with higher priority source", ip)
 		}
@@ -802,11 +802,11 @@ func (clients *clientsContainer) UpdateAddress(ip netip.Addr, host string, info
 func (clients *clientsContainer) addHostLocked(
 	ip netip.Addr,
 	host string,
-	src clientSource,
+	src client.Source,
 ) (ok bool) {
 	rc, ok := clients.ipToRC[ip]
 	if !ok {
-		if src < ClientSourceDHCP {
+		if src < client.SourceDHCP {
 			if clients.dhcp.HostByIP(ip) != "" {
 				return false
 			}
@@ -829,7 +829,7 @@ func (clients *clientsContainer) addHostLocked(
 }
 
 // rmHostsBySrc removes all entries that match the specified source.
-func (clients *clientsContainer) rmHostsBySrc(src clientSource) {
+func (clients *clientsContainer) rmHostsBySrc(src client.Source) {
 	n := 0
 	for ip, rc := range clients.ipToRC {
 		if rc.Source == src {
@@ -847,7 +847,7 @@ func (clients *clientsContainer) addFromHostsFile(hosts aghnet.Hosts) {
 	clients.lock.Lock()
 	defer clients.lock.Unlock()
 
-	clients.rmHostsBySrc(ClientSourceHostsFile)
+	clients.rmHostsBySrc(client.SourceHostsFile)
 
 	n := 0
 	for addr, rec := range hosts {
@@ -855,7 +855,7 @@ func (clients *clientsContainer) addFromHostsFile(hosts aghnet.Hosts) {
 		// hostname for the IP address.
 		//
 		// TODO(e.burkov):  Consider using all the names from all the records.
-		clients.addHostLocked(addr, rec[0].Names[0], ClientSourceHostsFile)
+		clients.addHostLocked(addr, rec[0].Names[0], client.SourceHostsFile)
 		n++
 	}
 
@@ -883,11 +883,11 @@ func (clients *clientsContainer) addFromSystemARP() {
 	clients.lock.Lock()
 	defer clients.lock.Unlock()
 
-	clients.rmHostsBySrc(ClientSourceARP)
+	clients.rmHostsBySrc(client.SourceARP)
 
 	added := 0
 	for _, n := range ns {
-		if clients.addHostLocked(n.IP, n.Name, ClientSourceARP) {
+		if clients.addHostLocked(n.IP, n.Name, client.SourceARP) {
 			added++
 		}
 	}
diff --git a/internal/home/clients_internal_test.go b/internal/home/clients_internal_test.go
index 5c92a896..b8ef598f 100644
--- a/internal/home/clients_internal_test.go
+++ b/internal/home/clients_internal_test.go
@@ -7,6 +7,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/AdguardTeam/AdGuardHome/internal/client"
 	"github.com/AdguardTeam/AdGuardHome/internal/dhcpd"
 	"github.com/AdguardTeam/AdGuardHome/internal/dhcpsvc"
 	"github.com/AdguardTeam/AdGuardHome/internal/filtering"
@@ -99,9 +100,9 @@ func TestClients(t *testing.T) {
 
 		assert.Equal(t, "client2", c.Name)
 
-		assert.Equal(t, clients.clientSource(cliNoneIP), ClientSourceNone)
-		assert.Equal(t, clients.clientSource(cli1IP), ClientSourcePersistent)
-		assert.Equal(t, clients.clientSource(cli2IP), ClientSourcePersistent)
+		assert.Equal(t, clients.clientSource(cliNoneIP), client.SourceNone)
+		assert.Equal(t, clients.clientSource(cli1IP), client.SourcePersistent)
+		assert.Equal(t, clients.clientSource(cli2IP), client.SourcePersistent)
 	})
 
 	t.Run("add_fail_name", func(t *testing.T) {
@@ -148,8 +149,8 @@ func TestClients(t *testing.T) {
 		})
 		require.NoError(t, err)
 
-		assert.Equal(t, clients.clientSource(cliOldIP), ClientSourceNone)
-		assert.Equal(t, clients.clientSource(cliNewIP), ClientSourcePersistent)
+		assert.Equal(t, clients.clientSource(cliOldIP), client.SourceNone)
+		assert.Equal(t, clients.clientSource(cliNewIP), client.SourcePersistent)
 
 		prev, ok = clients.list["client1"]
 		require.True(t, ok)
@@ -181,7 +182,7 @@ func TestClients(t *testing.T) {
 		ok := clients.Del("client1-renamed")
 		require.True(t, ok)
 
-		assert.Equal(t, clients.clientSource(netip.MustParseAddr("1.1.1.2")), ClientSourceNone)
+		assert.Equal(t, clients.clientSource(netip.MustParseAddr("1.1.1.2")), client.SourceNone)
 	})
 
 	t.Run("del_fail", func(t *testing.T) {
@@ -191,32 +192,32 @@ func TestClients(t *testing.T) {
 
 	t.Run("addhost_success", func(t *testing.T) {
 		ip := netip.MustParseAddr("1.1.1.1")
-		ok := clients.addHost(ip, "host", ClientSourceARP)
+		ok := clients.addHost(ip, "host", client.SourceARP)
 		assert.True(t, ok)
 
-		ok = clients.addHost(ip, "host2", ClientSourceARP)
+		ok = clients.addHost(ip, "host2", client.SourceARP)
 		assert.True(t, ok)
 
-		ok = clients.addHost(ip, "host3", ClientSourceHostsFile)
+		ok = clients.addHost(ip, "host3", client.SourceHostsFile)
 		assert.True(t, ok)
 
-		assert.Equal(t, clients.clientSource(ip), ClientSourceHostsFile)
+		assert.Equal(t, clients.clientSource(ip), client.SourceHostsFile)
 	})
 
 	t.Run("dhcp_replaces_arp", func(t *testing.T) {
 		ip := netip.MustParseAddr("1.2.3.4")
-		ok := clients.addHost(ip, "from_arp", ClientSourceARP)
+		ok := clients.addHost(ip, "from_arp", client.SourceARP)
 		assert.True(t, ok)
-		assert.Equal(t, clients.clientSource(ip), ClientSourceARP)
+		assert.Equal(t, clients.clientSource(ip), client.SourceARP)
 
-		ok = clients.addHost(ip, "from_dhcp", ClientSourceDHCP)
+		ok = clients.addHost(ip, "from_dhcp", client.SourceDHCP)
 		assert.True(t, ok)
-		assert.Equal(t, clients.clientSource(ip), ClientSourceDHCP)
+		assert.Equal(t, clients.clientSource(ip), client.SourceDHCP)
 	})
 
 	t.Run("addhost_fail", func(t *testing.T) {
 		ip := netip.MustParseAddr("1.1.1.1")
-		ok := clients.addHost(ip, "host1", ClientSourceRDNS)
+		ok := clients.addHost(ip, "host1", client.SourceRDNS)
 		assert.False(t, ok)
 	})
 }
@@ -239,7 +240,7 @@ func TestClientsWHOIS(t *testing.T) {
 
 	t.Run("existing_auto-client", func(t *testing.T) {
 		ip := netip.MustParseAddr("1.1.1.1")
-		ok := clients.addHost(ip, "host", ClientSourceRDNS)
+		ok := clients.addHost(ip, "host", client.SourceRDNS)
 		assert.True(t, ok)
 
 		clients.setWHOISInfo(ip, whois)
@@ -282,7 +283,7 @@ func TestClientsAddExisting(t *testing.T) {
 		assert.True(t, ok)
 
 		// Now add an auto-client with the same IP.
-		ok = clients.addHost(ip, "test", ClientSourceRDNS)
+		ok = clients.addHost(ip, "test", client.SourceRDNS)
 		assert.True(t, ok)
 	})
 
diff --git a/internal/home/clientshttp.go b/internal/home/clientshttp.go
index 6b49881c..62a46e78 100644
--- a/internal/home/clientshttp.go
+++ b/internal/home/clientshttp.go
@@ -8,6 +8,7 @@ import (
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghalg"
 	"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
+	"github.com/AdguardTeam/AdGuardHome/internal/client"
 	"github.com/AdguardTeam/AdGuardHome/internal/filtering"
 	"github.com/AdguardTeam/AdGuardHome/internal/schedule"
 	"github.com/AdguardTeam/AdGuardHome/internal/whois"
@@ -88,9 +89,9 @@ func (j *clientJSON) copySettings(
 type runtimeClientJSON struct {
 	WHOIS *whois.Info `json:"whois_info"`
 
-	IP     netip.Addr   `json:"ip"`
-	Name   string       `json:"name"`
-	Source clientSource `json:"source"`
+	IP     netip.Addr    `json:"ip"`
+	Name   string        `json:"name"`
+	Source client.Source `json:"source"`
 }
 
 type clientListJSON struct {
@@ -126,7 +127,7 @@ func (clients *clientsContainer) handleGetClients(w http.ResponseWriter, r *http
 	for _, l := range clients.dhcp.Leases() {
 		cj := runtimeClientJSON{
 			Name:   l.Hostname,
-			Source: ClientSourceDHCP,
+			Source: client.SourceDHCP,
 			IP:     l.IP,
 			WHOIS:  &whois.Info{},
 		}