SURT URL canicalization to handle non-UTF-8 percent-encoded characters

src/main/java/org/archive/url/BasicURLCanonicalizer.java

@@ -15,18 +15,18 @@
 /**
  * Canonicalizer that does more or less basic fixup. Based initially on rules
  * specified at <a href=
- * "https://developers.google.com/safe-browsing/developers_guide_v2#Canonicalization"
+ * "https://web.archive.org/web/20130306015559/https://developers.google.com/safe-browsing/developers_guide_v2#Canonicalization"
  * >https://developers.google.com/safe-browsing/developers_guide_v2#
- * Canonicalization</a>. These rules are designed for clients of google's
+ * Canonicalization</a>. These rules are designed for clients of Google's
  * "experimental" Safe Browsing API to "check URLs against Google's
  * constantly-updated blacklists of suspected phishing and malware pages".
  * 
  * <p>
- * This class differs from google in treatment of non-ascii input. Google's
+ * This class differs from Google in treatment of non-ascii input. Google's
  * rules don't really address this except with one example test case, which
  * seems to suggest taking raw input bytes and pct-encoding them byte for byte.
  * Since the input to this class consists of java strings, not raw bytes, that
- * wouldn't be possible, even if deemed preferable. Instead
+ * wouldn't be possible, even if deemed preferable. Instead,
  * BasicURLCanonicalizer expresses non-ascii characters pct-encoded UTF-8.
  */
 public class BasicURLCanonicalizer implements URLCanonicalizer {
@@ -212,6 +212,10 @@ protected static Charset UTF8() {
 		return _UTF8;
 	}
 
+	/**
+	 * @param input String to be percent-encoded. Assumed to be fully unescaped.
+	 * @return percent-encoded string
+	 */
 	public String escapeOnce(String input) {
 		if (input == null) {
 			return null;
@@ -243,6 +247,19 @@ public String escapeOnce(String input) {
 					 */
 					sb = new StringBuilder(input.substring(0, i));
 				}
+				if (b == '%' && i < utf8bytes.length - 2) {
+					// Any hex escapes left at this point represent non-UTF-8 encoded characters
+					// Unescape them, so they don't get double escaped
+					int hex1 = getHex(utf8bytes[i + 1]);
+					if (hex1 >= 0) {
+						int hex2 = getHex(utf8bytes[i + 2]);
+						if (hex2 >= 0) {
+							i = i+2;
+							b = hex1 * 16 + hex2;
+						}
+					}
+
+				}
 				sb.append("%");
 				String hex = Integer.toHexString(b).toUpperCase();
 				if (hex.length() == 1) {
@@ -337,7 +354,7 @@ public String decode(String input) {
 	 * Decodes bytes in bbuf as utf-8 and appends decoded characters to sb. If
 	 * decoding of any portion fails, appends the un-decodable %xx%xx sequence
 	 * extracted from inputStr instead of decoded characters. See "bad unicode"
-	 * tests in GoogleCanonicalizerTest#testDecode(). Variables only make sense
+	 * tests in BasicURLCanonicalizerTest#testDecode(). Variables only make sense
 	 * within context of {@link #decode(String)}.
 	 * 
 	 * @param sb

src/test/java/org/archive/url/BasicURLCanonicalizerTest.java

@@ -143,6 +143,9 @@ public void testUnescapeRepeatedly() {
 		assertEquals("%",guc.unescapeRepeatedly("%25%32%35"));
 
 		assertEquals("168.188.99.26",guc.unescapeRepeatedly("%31%36%38%2e%31%38%38%2e%39%39%2e%32%36"));
+
+		assertEquals("tag=%E4%EE%F8%EA%EE%EB%FC%ED%EE%E5",
+				guc.unescapeRepeatedly("tag=%E4%EE%F8%EA%EE%EB%FC%ED%EE%E5"));
 	}
 
 	public void testAttemptIPFormats() throws URIException {

src/test/java/org/archive/url/WaybackURLKeyMakerTest.java

@@ -26,6 +26,12 @@ public void testMakeKey() throws URISyntaxException {
 		assertEquals("192,211,203,34)/robots.txt", km.makeKey("https://34.203.211.192/robots.txt"));
 		assertEquals("2600:1f18:200d:fb00:2b74:867c:ab0c:150a)/robots.txt",
 				km.makeKey("https://[2600:1f18:200d:fb00:2b74:867c:ab0c:150a]/robots.txt"));
+		assertEquals("ua,1kr)/newslist.html?tag=%e4%ee%f8%ea%ee%eb%fc%ed%ee%e5",
+				km.makeKey("http://1kr.ua/newslist.html?tag=%E4%EE%F8%EA%EE%EB%FC%ED%EE%E5"));
+		assertEquals("com,aluroba)/tags/%c3%ce%ca%c7%d1%e5%c7.htm",
+				km.makeKey("http://www.aluroba.com/tags/%C3%CE%CA%C7%D1%E5%C7.htm"));
+		assertEquals("ac,insbase)/xoops2/modules/xpwiki?%a4%d5%a4%af%a4%aa%a4%ab%b8%a9%a4%aa%a4%aa%a4%ce%a4%b8%a4%e7%a4%a6%bb%d4",
+			km.makeKey("https://www.insbase.ac/xoops2/modules/xpwiki/?%A4%D5%A4%AF%A4%AA%A4%AB%B8%A9%A4%AA%A4%AA%A4%CE%A4%B8%A4%E7%A4%A6%BB%D4"));
 	}
 
 }