Better core logic for JWT; supports a more generic structure

router/tokens/parser.go

@@ -0,0 +1,33 @@
+package tokens
+
+import (
+	"github.com/gbrlsnchs/jwt/v3"
+	"github.com/pterodactyl/wings/config"
+	"time"
+)
+
+var alg *jwt.HMACSHA
+
+type TokenData interface {
+	GetPayload() *jwt.Payload
+}
+
+// Validates the provided JWT against the known secret for the Daemon and returns the
+// parsed data. This function DOES NOT validate that the token is valid for the connected
+// server, nor does it ensure that the user providing the token is able to actually do things.
+//
+// This simply returns a parsed token.
+func ParseToken(token []byte, data TokenData) error {
+	if alg == nil {
+		alg = jwt.NewHS256([]byte(config.Get().AuthenticationToken))
+	}
+
+	verifyOptions := jwt.ValidatePayload(
+		data.GetPayload(),
+		jwt.ExpirationTimeValidator(time.Now()),
+	)
+
+	_, err := jwt.Verify(token, alg, &data, verifyOptions)
+
+	return err
+}