fix: separate Base64 text encoding from payload charset

common/src/main/java/com/highgo/cloud/util/toolkit/Base64Util.java

@@ -19,6 +19,8 @@
 
 import com.highgo.cloud.util.toolkit.support.Charsets;
 
+import java.nio.charset.StandardCharsets;
+
 /**
  * Base64工具
  *
@@ -45,7 +47,7 @@ public static String encode(String value) {
      */
     public static String encode(String value, java.nio.charset.Charset charset) {
         byte[] val = value.getBytes(charset);
-        return new String(Base64Util.encode(val), charset);
+        return new String(Base64Util.encode(val), StandardCharsets.US_ASCII);
     }
 
     /**
@@ -67,7 +69,7 @@ public static String encodeUrlSafe(String value) {
      */
     public static String encodeUrlSafe(String value, java.nio.charset.Charset charset) {
         byte[] val = value.getBytes(charset);
-        return new String(Base64Util.encodeUrlSafe(val), charset);
+        return new String(Base64Util.encodeUrlSafe(val), StandardCharsets.US_ASCII);
     }
 
     /**
@@ -88,7 +90,7 @@ public static String decode(String value) {
      * @return {String}
      */
     public static String decode(String value, java.nio.charset.Charset charset) {
-        byte[] val = value.getBytes(charset);
+        byte[] val = value.getBytes(StandardCharsets.US_ASCII);
         byte[] decodedValue = Base64Util.decode(val);
         return new String(decodedValue, charset);
     }
@@ -111,7 +113,7 @@ public static String decodeUrlSafe(String value) {
      * @return {String}
      */
     public static String decodeUrlSafe(String value, java.nio.charset.Charset charset) {
-        byte[] val = value.getBytes(charset);
+        byte[] val = value.getBytes(StandardCharsets.US_ASCII);
         byte[] decodedValue = Base64Util.decodeUrlSafe(val);
         return new String(decodedValue, charset);
     }

tests/Base64CharsetRegression.java

@@ -0,0 +1,79 @@
+import com.highgo.cloud.util.toolkit.Base64Util;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+import java.util.Base64;
+
+/** Calls the complete production codec; JDK Base64 is the independent oracle. */
+public final class Base64CharsetRegression {
+    private static int failures;
+
+    private interface CheckedCase {
+        void run();
+    }
+
+    private static void check(String name, CheckedCase test) {
+        try {
+            test.run();
+            System.out.println("PASS " + name);
+        } catch (RuntimeException | AssertionError failure) {
+            failures++;
+            System.err.println("FAIL " + name + ": " + failure);
+        }
+    }
+
+    private static void equal(String expected, String actual) {
+        if (!expected.equals(actual)) {
+            throw new AssertionError("expected <" + expected + "> but was <" + actual + ">");
+        }
+    }
+
+    private static String expected(String payload, Charset charset, boolean urlSafe) {
+        Base64.Encoder encoder = urlSafe ? Base64.getUrlEncoder() : Base64.getEncoder();
+        return encoder.encodeToString(payload.getBytes(charset));
+    }
+
+    private static String encode(String payload, Charset charset, boolean urlSafe) {
+        return urlSafe ? Base64Util.encodeUrlSafe(payload, charset) : Base64Util.encode(payload, charset);
+    }
+
+    private static String decode(String encoded, Charset charset, boolean urlSafe) {
+        return urlSafe ? Base64Util.decodeUrlSafe(encoded, charset) : Base64Util.decode(encoded, charset);
+    }
+
+    private static void runMode(boolean urlSafe) {
+        String prefix = urlSafe ? "url-safe-" : "basic-";
+        check(prefix + "UTF16-ASCII-carrier", () ->
+                equal(expected("A", StandardCharsets.UTF_16, urlSafe),
+                        encode("A", StandardCharsets.UTF_16, urlSafe)));
+        check(prefix + "UTF16-canonical-decode", () ->
+                equal("A", decode(expected("A", StandardCharsets.UTF_16, urlSafe),
+                        StandardCharsets.UTF_16, urlSafe)));
+        check(prefix + "UTF16-round-trip", () ->
+                equal("A", decode(encode("A", StandardCharsets.UTF_16, urlSafe),
+                        StandardCharsets.UTF_16, urlSafe)));
+        check(prefix + "UTF16LE-ASCII-carrier", () ->
+                equal(expected("A", StandardCharsets.UTF_16LE, urlSafe),
+                        encode("A", StandardCharsets.UTF_16LE, urlSafe)));
+        check(prefix + "default-UTF8-control", () -> {
+            String payload = "\u4e2d\u6587";
+            String encoded = urlSafe ? Base64Util.encodeUrlSafe(payload) : Base64Util.encode(payload);
+            equal(expected(payload, StandardCharsets.UTF_8, urlSafe), encoded);
+            equal(payload, urlSafe ? Base64Util.decodeUrlSafe(encoded) : Base64Util.decode(encoded));
+        });
+        check(prefix + "explicit-Latin1-control", () -> {
+            String payload = "caf\u00e9";
+            String encoded = encode(payload, StandardCharsets.ISO_8859_1, urlSafe);
+            equal(expected(payload, StandardCharsets.ISO_8859_1, urlSafe), encoded);
+            equal(payload, decode(encoded, StandardCharsets.ISO_8859_1, urlSafe));
+        });
+    }
+
+    public static void main(String[] args) {
+        runMode(false);
+        runMode(true);
+        if (failures != 0) {
+            throw new AssertionError(failures + " codec cases failed");
+        }
+    }
+}
+