httputil: fix ParseIP usage

The string fed into the ParseIP function needs to not have a port.
This does that and adds a test to check the desired behavior.

Closes: #1689
Signed-off-by: Hank Donnay <hdonnay@redhat.com>
(cherry picked from commit b18f989)

internal/httputil/client.go

@@ -50,14 +50,23 @@ func ctlLocalOnly(network, address string, _ syscall.RawConn) error {
 			Err:  "disallowed by policy",
 		}
 	}
-	addr := net.ParseIP(address)
+	host, _, err := net.SplitHostPort(address)
+	if err != nil {
+		return &net.AddrError{
+			Addr: network + "!" + address,
+			Err:  "martian address",
+		}
+	}
+	addr := net.ParseIP(host)
 	if addr == nil {
 		return &net.AddrError{
 			Addr: network + "!" + address,
 			Err:  "martian address",
 		}
 	}
-	if !addr.IsPrivate() {
+	if !addr.IsPrivate() &&
+		!addr.IsLoopback() &&
+		!addr.IsLinkLocalUnicast() {
 		return &net.AddrError{
 			Addr: network + "!" + address,
 			Err:  "disallowed by policy",

internal/httputil/client_test.go

@@ -0,0 +1,57 @@
+package httputil
+
+import (
+	"errors"
+	"net"
+	"testing"
+)
+
+func TestLocalOnly(t *testing.T) {
+	tt := []struct {
+		Network string
+		Addr    string
+		Err     *net.AddrError
+	}{
+		{
+			Network: "tcp4",
+			Addr:    "192.168.0.1:443",
+			Err:     nil,
+		},
+		{
+			Network: "tcp4",
+			Addr:    "127.0.0.1:443",
+			Err:     nil,
+		},
+		{
+			Network: "tcp6",
+			Addr:    "[fe80::]:443",
+			Err:     nil,
+		},
+		{
+			Network: "tcp4",
+			Addr:    "8.8.8.8:443",
+			Err: &net.AddrError{
+				Addr: "tcp4!8.8.8.8:443",
+				Err:  "disallowed by policy",
+			},
+		},
+		{
+			Network: "tcp6",
+			Addr:    "[2000::]:443",
+			Err: &net.AddrError{
+				Addr: "tcp6![2000::]:443",
+				Err:  "disallowed by policy",
+			},
+		},
+	}
+	for _, tc := range tt {
+		t.Logf("%s!%s", tc.Network, tc.Addr)
+		var nErr *net.AddrError
+		got := ctlLocalOnly(tc.Network, tc.Addr, nil)
+		if errors.As(got, &nErr) {
+			if tc.Err.Err != nErr.Err || tc.Err.Addr != nErr.Addr {
+				t.Errorf("got: %v, want: %v", got, tc.Err)
+			}
+		}
+	}
+}