feat: downgrade RSC-004 (cannot decrypt resource) to INFO (#1136)

rdeltour · web-flow · commit e7320689abbb · 2020-05-01T17:07:29.000+02:00
feat: downgrade RSC-004 (cannot decrypt resource) to INFO

An INFO better describes EPUBCheck’s inability to decrypt or de-obfuscate
a resource. RSC-004 does not necessarily means the content is invalid,
but it means EPUBCheck is unable to process it.

- All the incomplete `EncryptionFilter` implementations now accurately
report they cannot decrypt related content.
- Validation will abort early for encrypted (or obfuscated) files,
reporting RSC-004 as an INFO message.

Fixes 1077, caused by an attempt to parse an obfuscated SVG document
which was falsely assumed decryptable by the lying `EncryptionFilter`
(boo).
diff --git a/src/main/java/com/adobe/epubcheck/messages/DefaultSeverities.java b/src/main/java/com/adobe/epubcheck/messages/DefaultSeverities.java
@@ -293,7 +293,7 @@ private void initialize()
     severities.put(MessageId.RSC_001, Severity.ERROR);
     severities.put(MessageId.RSC_002, Severity.FATAL);
     severities.put(MessageId.RSC_003, Severity.ERROR);
-    severities.put(MessageId.RSC_004, Severity.ERROR);
+    severities.put(MessageId.RSC_004, Severity.INFO);
     severities.put(MessageId.RSC_005, Severity.ERROR);
     severities.put(MessageId.RSC_006, Severity.ERROR);
     severities.put(MessageId.RSC_006b, Severity.USAGE);
diff --git a/src/main/java/com/adobe/epubcheck/ocf/AdobeFontManglingFilter.java b/src/main/java/com/adobe/epubcheck/ocf/AdobeFontManglingFilter.java
@@ -13,10 +13,9 @@ public AdobeFontManglingFilter(String Uid)
 
   public boolean canDecrypt()
   {
-    //FIXME we force return true to not issue a false-positive warning (see Issue 220)
-    // ultimately, we need to pass the concatenated publication IDs (encryption key)
+    //TODO we need to pass the concatenated publication IDs (encryption key)
     // and implement de-obfuscation.
-    return true;
+    return false;
 //		return uniqueIdentifier != null;
   }
 
diff --git a/src/main/java/com/adobe/epubcheck/ocf/IDPFFontManglingFilter.java b/src/main/java/com/adobe/epubcheck/ocf/IDPFFontManglingFilter.java
@@ -13,10 +13,9 @@ public IDPFFontManglingFilter(String Uid)
 
   public boolean canDecrypt()
   {
-    //FIXME we force return true to not issue a false-positive warning (see Issue 220)
-    // ultimately, we need to pass the concatenated publication IDs (encryption key)
+    // TODO we need to pass the concatenated publication IDs (encryption key)
     // and implement de-obfuscation.
-    return true;
+    return false;
 //		return uniqueIdentifier != null;
   }
 
diff --git a/src/test/java/com/adobe/epubcheck/api/Epub30CheckExpandedTest.java b/src/test/java/com/adobe/epubcheck/api/Epub30CheckExpandedTest.java
@@ -1412,7 +1412,7 @@ public void testDuplicateResources()
 
   @Test
   public void testEncryption_Unknown(){
-    expectedErrors.add(MessageId.RSC_004);
+    expectedInfos.add(MessageId.RSC_004);
     testValidateDocument("invalid/encryption-unknown");
   }
   
@@ -1472,4 +1472,11 @@ public void testEncryption_DuplicateIDs()
     Collections.addAll(expectedErrors, MessageId.RSC_005, MessageId.RSC_005);
     testValidateDocument("invalid/encryption-duplicate-ids");
   }
+
+  @Test
+  public void testObfuscatedSVG()
+  {
+    expectedInfos.add(MessageId.RSC_004);
+    testValidateDocument("valid/container-obfuscation-svg-valid");
+  }
 }
diff --git a/src/test/java/com/adobe/epubcheck/api/Epub30CheckTest.java b/src/test/java/com/adobe/epubcheck/api/Epub30CheckTest.java
@@ -198,6 +198,7 @@ public void testValidateEPUB30Issue289()
   @Test
   public void testValidateEPUB30FontObfuscation()
   {
+    Collections.addAll(expectedInfos, MessageId.RSC_004);
     testValidateDocument("valid/font-obfuscation.epub");
   }
 
diff --git a/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/EPUB/content_001.xhtml b/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/EPUB/content_001.xhtml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<title>Minimal EPUB</title>
+	</head>
+	<body epub:type="bodymatter">
+		<h1>Loomings</h1>
+		<p>Call me Ishmael.</p>
+		<img src="emoji.svg" alt="a smiling emoji" />
+	</body>
+</html>
diff --git a/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/EPUB/emoji.svg b/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/EPUB/emoji.svg
diff --git a/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/EPUB/nav.xhtml b/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/EPUB/nav.xhtml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<title>Minimal Nav</title>
+	</head>
+	<body>
+		<nav epub:type="toc">
+			<ol>
+				<li><a href="content_001.xhtml">content 001</a></li>
+			</ol>
+		</nav>
+		<nav epub:type="landmarks">
+			<ol>
+				<li><a href="content_001.xhtml" epub:type="bodymatter">Start Reading</a></li>
+			</ol>
+		</nav>
+	</body>
+</html>
diff --git a/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/EPUB/package.opf b/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/EPUB/package.opf
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<package xmlns="http://www.idpf.org/2007/opf" version="3.0" xml:lang="en" unique-identifier="q">
+<metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <dc:title id="title">Minimal EPUB 3.0</dc:title>
+  <dc:language>en</dc:language>
+  <dc:identifier id="q">NOID</dc:identifier>
+  <meta property="dcterms:modified">2017-06-14T00:00:01Z</meta>
+</metadata>
+<manifest>
+  <item id="content_001"  href="content_001.xhtml" media-type="application/xhtml+xml"/>
+  <item id="nav"  href="nav.xhtml" media-type="application/xhtml+xml" properties="nav"/>
+  <item id="emoji" href="emoji.svg" media-type="image/svg+xml"/>
+</manifest>
+<spine>
+  <itemref idref="content_001" />
+</spine>
+</package>
diff --git a/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/META-INF/container.xml b/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/META-INF/container.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
+   <rootfiles>
+      <rootfile full-path="EPUB/package.opf" media-type="application/oebps-package+xml"/>
+   </rootfiles>
+</container>
diff --git a/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/META-INF/encryption.xml b/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/META-INF/encryption.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<encryption xmlns="urn:oasis:names:tc:opendocument:xmlns:container"
+  xmlns:enc="http://www.w3.org/2001/04/xmlenc#">
+  <enc:EncryptedData>
+    <enc:EncryptionMethod Algorithm="http://www.idpf.org/2008/embedding"/>
+    <enc:CipherData>
+      <enc:CipherReference URI="EPUB/emoji.svg"/>
+    </enc:CipherData>
+  </enc:EncryptedData>
+</encryption>
diff --git a/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/mimetype b/src/test/resources/30/expanded/valid/container-obfuscation-svg-valid/mimetype
@@ -0,0 +1 @@
+application/epub+zip
diff --git a/src/test/resources/com/adobe/epubcheck/test/css/font_encryption_adobe_expected_results.json b/src/test/resources/com/adobe/epubcheck/test/css/font_encryption_adobe_expected_results.json
@@ -320,5 +320,17 @@
       "context" : null
     } ],
     "suggestion" : null
+  }, {
+    "ID" : "RSC-004",
+    "severity" : "INFO",
+    "message" : "File \"OEBPS/fonts/ChaparralPro-Regular.otf\" could not be decrypted.",
+    "additionalLocations" : 0,
+    "locations" : [ {
+      "path" : "font_encryption_adobe.epub",
+      "line" : -1,
+      "column" : -1,
+      "context" : null
+    } ],
+    "suggestion" : null
   } ]
 }
diff --git a/src/test/resources/com/adobe/epubcheck/test/css/font_encryption_unknown_expected_results.json b/src/test/resources/com/adobe/epubcheck/test/css/font_encryption_unknown_expected_results.json
@@ -7,7 +7,7 @@
     "checkDate" : "09-05-2014 03:17:17",
     "elapsedTime" : 25,
     "nFatal" : 0,
-    "nError" : 2,
+    "nError" : 1,
     "nWarning" : 0,
     "nUsage" : 6
   },
@@ -322,7 +322,7 @@
     "suggestion" : null
   }, {
     "ID" : "RSC-004",
-    "severity" : "ERROR",
+    "severity" : "INFO",
     "message" : "File \"OEBPS/fonts/ChaparralPro-Regular.otf\" could not be decrypted.",
     "additionalLocations" : 0,
     "locations" : [ {
diff --git a/src/test/resources/com/adobe/epubcheck/test/encryption/epub20_encryption_binary_content.epub_expected_results.xml b/src/test/resources/com/adobe/epubcheck/test/encryption/epub20_encryption_binary_content.epub_expected_results.xml
@@ -12,7 +12,6 @@
   <version>2.0.1</version>
   <status>Not well-formed</status>
   <messages>
-   <message severity="error" subMessage="RSC-004">RSC-004, ERROR, [File 'OEBPS/Text/pdfMigration.html' could not be decrypted.], epub20_encryption_binary_content.epub</message>
    <message severity="error" subMessage="RSC-012">RSC-012, ERROR, [Fragment identifier is not defined.], OEBPS/toc.ncx (24-67)</message>
    <message severity="error" subMessage="RSC-012">RSC-012, ERROR, [Fragment identifier is not defined.], OEBPS/toc.ncx (30-82)</message>
    <message severity="error" subMessage="RSC-012">RSC-012, ERROR, [Fragment identifier is not defined.], OEBPS/toc.ncx (36-81)</message>
diff --git a/src/test/resources/com/adobe/epubcheck/test/encryption/epub20_minimal_encryption.epub_expected_results.xml b/src/test/resources/com/adobe/epubcheck/test/encryption/epub20_minimal_encryption.epub_expected_results.xml
@@ -12,7 +12,6 @@
   <version>2.0.1</version>
   <status>Not well-formed</status>
   <messages>
-   <message severity="error" subMessage="RSC-004">RSC-004, ERROR, [File 'OEBPS/Text/pdfMigration.html' could not be decrypted.], epub20_minimal_encryption.epub</message>
    <message severity="error" subMessage="RSC-012">RSC-012, ERROR, [Fragment identifier is not defined.], OEBPS/toc.ncx (24-67)</message>
    <message severity="error" subMessage="RSC-012">RSC-012, ERROR, [Fragment identifier is not defined.], OEBPS/toc.ncx (30-82)</message>
    <message severity="error" subMessage="RSC-012">RSC-012, ERROR, [Fragment identifier is not defined.], OEBPS/toc.ncx (36-81)</message>

Original file line number	Diff line number	Diff line change
`@@ -13,10 +13,9 @@ public AdobeFontManglingFilter(String Uid)`
`13`	`13`
`14`	`14`	`public boolean canDecrypt()`
`15`	`15`	`{`
`16`		`- //FIXME we force return true to not issue a false-positive warning (see Issue 220)`
`17`		`- // ultimately, we need to pass the concatenated publication IDs (encryption key)`
	`16`	`+ //TODO we need to pass the concatenated publication IDs (encryption key)`
`18`	`17`	`// and implement de-obfuscation.`
`19`		`- return true;`
	`18`	`+ return false;`
`20`	`19`	`// return uniqueIdentifier != null;`
`21`	`20`	`}`
`22`	`21`
Original file line number	Diff line number	Diff line change
`@@ -13,10 +13,9 @@ public IDPFFontManglingFilter(String Uid)`
`13`	`13`
`14`	`14`	`public boolean canDecrypt()`
`15`	`15`	`{`
`16`		`- //FIXME we force return true to not issue a false-positive warning (see Issue 220)`
`17`		`- // ultimately, we need to pass the concatenated publication IDs (encryption key)`
	`16`	`+ // TODO we need to pass the concatenated publication IDs (encryption key)`
`18`	`17`	`// and implement de-obfuscation.`
`19`		`- return true;`
	`18`	`+ return false;`
`20`	`19`	`// return uniqueIdentifier != null;`
`21`	`20`	`}`
`22`	`21`
Original file line number	Diff line number	Diff line change
`@@ -1412,7 +1412,7 @@ public void testDuplicateResources()`
`1412`	`1412`
`1413`	`1413`	`@Test`
`1414`	`1414`	`public void testEncryption_Unknown(){`
`1415`		`- expectedErrors.add(MessageId.RSC_004);`
	`1415`	`+ expectedInfos.add(MessageId.RSC_004);`
`1416`	`1416`	`testValidateDocument("invalid/encryption-unknown");`
`1417`	`1417`	`}`
`1418`	`1418`
`@@ -1472,4 +1472,11 @@ public void testEncryption_DuplicateIDs()`
`1472`	`1472`	`Collections.addAll(expectedErrors, MessageId.RSC_005, MessageId.RSC_005);`
`1473`	`1473`	`testValidateDocument("invalid/encryption-duplicate-ids");`
`1474`	`1474`	`}`
	`1475`	`+`
	`1476`	`+ @Test`
	`1477`	`+ public void testObfuscatedSVG()`
	`1478`	`+ {`
	`1479`	`+ expectedInfos.add(MessageId.RSC_004);`
	`1480`	`+ testValidateDocument("valid/container-obfuscation-svg-valid");`
	`1481`	`+ }`
`1475`	`1482`	`}`
Original file line number	Diff line number	Diff line change
`@@ -198,6 +198,7 @@ public void testValidateEPUB30Issue289()`
`198`	`198`	`@Test`
`199`	`199`	`public void testValidateEPUB30FontObfuscation()`
`200`	`200`	`{`
	`201`	`+ Collections.addAll(expectedInfos, MessageId.RSC_004);`
`201`	`202`	`testValidateDocument("valid/font-obfuscation.epub");`
`202`	`203`	`}`
`203`	`204`