VAPID config and push subscription API (Feature 19) (#153)

Co-authored-by: orchestrator-agent <20+orchestrator-agent@code.cubecraftcreations.com>

internal/vapid/vapid_test.go

@@ -0,0 +1,92 @@
+package vapid
+
+import (
+	"encoding/base64"
+	"strings"
+	"testing"
+)
+
+func TestGenerateRoundTrips(t *testing.T) {
+	t.Parallel()
+	a, err := Generate()
+	if err != nil {
+		t.Fatal(err)
+	}
+	b, err := Generate()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if a == b {
+		t.Fatal("two generated key pairs are equal")
+	}
+	// 65 and 32 bytes in unpadded base64url.
+	if len(a.PublicKey) != 87 || len(a.PrivateKey) != 43 {
+		t.Errorf("key lengths = %d, %d; want 87, 43", len(a.PublicKey), len(a.PrivateKey))
+	}
+	pub, err := ParsePublicKey(a.PublicKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	priv, err := ParsePrivateKey(a.PrivateKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := CheckPair(pub, priv); err != nil {
+		t.Errorf("CheckPair of a generated pair: %v", err)
+	}
+	other, err := ParsePrivateKey(b.PrivateKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := CheckPair(pub, other); err != ErrMismatch {
+		t.Errorf("CheckPair of mismatched keys = %v, want ErrMismatch", err)
+	}
+}
+
+func TestParseRejectsMalformedKeys(t *testing.T) {
+	t.Parallel()
+	pair, err := Generate()
+	if err != nil {
+		t.Fatal(err)
+	}
+	raw := func(b []byte) string { return base64.RawURLEncoding.EncodeToString(b) }
+	compressed, _ := base64.RawURLEncoding.DecodeString(pair.PublicKey)
+	compressed = append([]byte{0x02}, compressed[1:33]...)
+	offCurve := make([]byte, 65)
+	offCurve[0] = 0x04
+	offCurve[64] = 1
+	order := []byte{ // the P-256 group order n, not a valid scalar
+		0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+		0xbc, 0xe6, 0xfa, 0xad, 0xa7, 0x17, 0x9e, 0x84, 0xf3, 0xb9, 0xca, 0xc2, 0xfc, 0x63, 0x25, 0x51,
+	}
+
+	for name, s := range map[string]string{
+		"empty":          "",
+		"padded":         pair.PublicKey + "=",
+		"standard alpha": strings.NewReplacer("-", "+", "_", "/").Replace(pair.PublicKey) + "+/",
+		"compressed":     raw(compressed),
+		"off curve":      raw(offCurve),
+		"private key":    pair.PrivateKey,
+	} {
+		if _, err := ParsePublicKey(s); err == nil {
+			t.Errorf("ParsePublicKey(%s) succeeded", name)
+		}
+	}
+	for name, s := range map[string]string{
+		"empty":      "",
+		"padded":     pair.PrivateKey + "=",
+		"PEM":        "-----BEGIN EC PRIVATE KEY-----",
+		"zero":       raw(make([]byte, 32)),
+		"group size": raw(order),
+		"public key": pair.PublicKey,
+	} {
+		_, err := ParsePrivateKey(s)
+		if err == nil {
+			t.Errorf("ParsePrivateKey(%s) succeeded", name)
+			continue
+		}
+		if s != "" && strings.Contains(err.Error(), s) {
+			t.Errorf("ParsePrivateKey(%s) error quotes the key: %v", name, err)
+		}
+	}
+}