Add fallback to pretty print invalid UTF8 data.

Malformed UTF8 data can cause the escaping code to fail. Capture the
failures and print out a hex version with error note.

Author: davidlehn

CHANGELOG.md

@@ -1,6 +1,11 @@
 Forge ChangeLog
 ===============
 
+## 1.3.0 - 2022-XXX
+
+### Fixed
+- [asn1] Add fallback to pretty print invalid UTF8 data.
+
 ## 1.2.1 - 2022-01-11
 
 ### Fixed

lib/asn1.js

@@ -1391,7 +1391,16 @@ asn1.prettyPrint = function(obj, level, indentation) {
       }
       rval += '0x' + forge.util.bytesToHex(obj.value);
     } else if(obj.type === asn1.Type.UTF8) {
-      rval += forge.util.decodeUtf8(obj.value);
+      try {
+        rval += forge.util.decodeUtf8(obj.value);
+      } catch(e) {
+        if(e.message === 'URI malformed') {
+          rval +=
+            '0x' + forge.util.bytesToHex(obj.value) + ' (malformed UTF8)';
+        } else {
+          throw e;
+        }
+      }
     } else if(obj.type === asn1.Type.PRINTABLESTRING ||
       obj.type === asn1.Type.IA5String) {
       rval += obj.value;