Made ignoreCRCMismatches property public, so it can be set by an API …

…consumer, for purposes such as implementing a user preference to always ignore mismatches for a given file (or all files, etc.) (Issue #82)

Classes/URKArchive.h

@@ -25,7 +25,7 @@ DllHppIgnore
 typedef NS_ENUM(NSInteger, URKErrorCode) {
 
     /**
-     *  The archive's header is empty
+     *  The last file of the archive has been read
      */
     URKErrorCodeEndOfArchive = ERAR_END_ARCHIVE,
 
@@ -35,7 +35,7 @@ typedef NS_ENUM(NSInteger, URKErrorCode) {
     URKErrorCodeNoMemory = ERAR_NO_MEMORY,
 
     /**
-     *  The header is broken
+     *  The header's CRC doesn't match the decompressed data's CRC
      */
     URKErrorCodeBadData = ERAR_BAD_DATA,
 
@@ -173,6 +173,17 @@ extern NSString *URKErrorDomain;
  */
 @property(nullable, strong) NSProgress *progress;
 
+/**
+ *  When performing operations on a RAR archive, the contents of compressed files are checked
+ *  against the record of what they were when the archive was created. If there's a mismatch,
+ *  either the metadata (header) or archive contents have become corrupted. You can defeat this check by
+ *  setting this property to YES, though there may be security implications to turning the
+ *  warnings off, as it may indicate a maliciously crafted archive intended to exploit a vulnerability.
+ *
+ *  It's recommended to leave the decision of how to treat archives with mismatched CRCs to the user
+ */
+@property (assign) BOOL ignoreCRCMismatches;
+
 
 /**
  *  **DEPRECATED:** Creates and returns an archive at the given path
@@ -475,16 +486,16 @@ extern NSString *URKErrorDomain;
 - (BOOL)validatePassword;
 
 /**
- Extract each file in the archive, checking whether the data matches the CRC checksum
- stored at the time it was written
+ Iterate through the archive, checking for any errors, including CRC mismatches between
+ the archived file and its header
  
- @return YES if the data is all correct, false if any check failed
+ @return YES if the data is all correct, false if any check failed (_even if ignoreCRCMismatches is YES_)
  */
 - (BOOL)checkDataIntegrity;
 
 /**
- Extract each file in the archive, checking whether the data matches the CRC checksum
- stored at the time it was written. If any file doesn't match, run the given block
+ Iterate through the archive, checking for any errors, including CRC mismatches between
+ the archived file and its header. If any file's CRC doesn't match, run the given block
  to allow the API consumer to decide whether to ignore mismatches. NOTE: This may be a
  security risk. The block is intended to prompt the user, which is why it's forced onto
  the main thread, rather than making a design-time decision
@@ -502,7 +513,7 @@ extern NSString *URKErrorDomain;
 - (BOOL)checkDataIntegrityIgnoringCRCMismatches:(BOOL(^)(void))ignoreCRCMismatches;
 
 /**
- Extract a particular file, to determine if its data matches the CRC
+ Check a particular file, to determine if its data matches the CRC
  checksum stored at the time it written
 
  @param filePath The file in the archive to check

Classes/URKArchive.mm

@@ -53,7 +53,6 @@ - (instancetype)initWithFile:(NSURL *)fileURL password:(NSString*)password error
 
 @property (assign) NSString *lastArchivePath;
 @property (assign) NSString *lastFilepath;
-@property (assign) BOOL ignoreCRCMismatches;
 
 @end
 

Tests/CheckDataTests.m

@@ -47,6 +47,16 @@ - (void)testCheckDataIntegrity_ModifiedCRC {
     XCTAssertFalse(success, @"Data integrity check passed for archive with a modified CRC");
 }
 
+- (void)testCheckDataIntegrity_ModifiedCRC_IgnoringMismatches {
+    NSURL *testArchiveURL = self.testFileURLs[@"Modified CRC Archive.rar"];
+    URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
+    archive.ignoreCRCMismatches = YES;
+
+    // Still expect failure, so a consumer can still tell that data is mismatched
+    BOOL success = [archive checkDataIntegrity];
+    XCTAssertFalse(success, @"Data integrity check passed for archive with a modified CRC");
+}
+
 #pragma mark - checkDataIntegrityOfFile
 
 - (void)testCheckDataIntegrityForFile {
@@ -91,6 +101,16 @@ - (void)testCheckDataIntegrityForFile_ModifiedCRC {
     XCTAssertFalse(success, @"Data integrity check passed for archive with modified CRC");
 }
 
+- (void)testCheckDataIntegrityForFile_ModifiedCRC_IgnoringMismatches {
+    NSURL *testArchiveURL = self.testFileURLs[@"Modified CRC Archive.rar"];
+    URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
+    archive.ignoreCRCMismatches = YES;
+
+    // Still expect failure, so a consumer can still tell that data is mismatched
+    BOOL success = [archive checkDataIntegrityOfFile:@"README.md"];
+    XCTAssertFalse(success, @"Data integrity check passed for archive with modified CRC");
+}
+
 - (void)testCheckDataIntegrityIgnoringCRCMismatches {
     NSArray *testArchives = @[@"Test Archive.rar",
                               @"Test Archive (Password).rar",
@@ -112,7 +132,8 @@ - (void)testCheckDataIntegrityIgnoringCRCMismatches {
 
         XCTAssertTrue(success, @"Data integrity check failed for %@", testArchiveName);
         XCTAssertFalse(blockInvoked, @"Block prompting whether to ignore CRC mismatches should not have been called");
-    }
+        XCTAssertFalse(archive.ignoreCRCMismatches);
+ }
 }
 
 - (void)testCheckDataIntegrityIgnoringCRCMismatches_InBackground {
@@ -137,6 +158,7 @@ - (void)testCheckDataIntegrityIgnoringCRCMismatches_InBackground {
     [self waitForExpectationsWithTimeout:10 handler:nil];
     XCTAssertTrue(blockInvoked, @"Block prompting whether to ignore CRC mismatches should have been called");
     XCTAssertEqualObjects(blockThread, [NSThread mainThread]);
+    XCTAssertTrue(archive.ignoreCRCMismatches);
 }
 
 - (void)testCheckDataIntegrityIgnoringCRCMismatches_NotAnArchive {
@@ -151,6 +173,7 @@ - (void)testCheckDataIntegrityIgnoringCRCMismatches_NotAnArchive {
 
     XCTAssertFalse(success, @"Data integrity check passed for non-archive");
     XCTAssertFalse(blockInvoked, @"Block prompting whether to ignore CRC mismatches should not have been called");
+    XCTAssertFalse(archive.ignoreCRCMismatches);
 }
 
 - (void)testCheckDataIntegrityIgnoringCRCMismatches_ModifiedCRC_Ignore {
@@ -165,6 +188,7 @@ - (void)testCheckDataIntegrityIgnoringCRCMismatches_ModifiedCRC_Ignore {
 
     XCTAssertTrue(success, @"Data integrity check failed for archive with modified CRC, when instructed to ignore");
     XCTAssertTrue(blockInvoked, @"Block prompting whether to ignore CRC mismatches should have been called");
+    XCTAssertTrue(archive.ignoreCRCMismatches);
 }
 
 - (void)testCheckDataIntegrityIgnoringCRCMismatches_ModifiedCRC_DontIgnore {
@@ -179,6 +203,7 @@ - (void)testCheckDataIntegrityIgnoringCRCMismatches_ModifiedCRC_DontIgnore {
 
     XCTAssertFalse(success, @"Data integrity check passed for archive with modified CRC");
     XCTAssertTrue(blockInvoked, @"Block prompting whether to ignore CRC mismatches should have been called");
+    XCTAssertFalse(archive.ignoreCRCMismatches);
 }
 
 @end

Tests/ExtractBufferedDataTests.m

@@ -82,12 +82,7 @@ - (void)testExtractBufferedData_ModifiedCRC_IgnoringMismatches
     NSURL *archiveURL = self.testFileURLs[@"Modified CRC Archive.rar"];
     NSString *extractedFile = @"README.md";
     URKArchive *archive = [[URKArchive alloc] initWithURL:archiveURL error:nil];
-
-    BOOL checkIntegritySuccess = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return YES;
-    }];
-
-    XCTAssertTrue(checkIntegritySuccess, @"Data integrity check failed for archive with modified CRC, when instructed to ignore");
+    archive.ignoreCRCMismatches = YES;
 
     NSError *error = nil;
     NSMutableData *reconstructedFile = [NSMutableData data];

Tests/ExtractDataTests.m

@@ -136,12 +136,7 @@ - (void)testExtractData_ModifiedCRC
 - (void)testExtractData_ModifiedCRC_IgnoringMismatches
 {
     URKArchive *archive = [[URKArchive alloc] initWithURL:self.testFileURLs[@"Modified CRC Archive.rar"] error:nil];
-
-    BOOL checkIntegritySuccess = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return YES;
-    }];
-
-    XCTAssertTrue(checkIntegritySuccess, @"Data integrity check failed for archive with modified CRC, when instructed to ignore");
+    archive.ignoreCRCMismatches = YES;
 
     NSError *error = nil;
     NSData *data = [archive extractDataFromFile:@"README.md" error:&error];

Tests/ExtractFilesTests.m

@@ -265,13 +265,8 @@ - (void)testExtractFiles_ModifiedCRC_IgnoreCRCMismatches
     NSFileManager *fm = [NSFileManager defaultManager];
 
     URKArchive *archive = [[URKArchive alloc] initWithURL:self.testFileURLs[@"Modified CRC Archive.rar"] error:nil];
-
-    BOOL fileHasIntegrity = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return YES;
-    }];
-
-    XCTAssertTrue(fileHasIntegrity);
-
+    archive.ignoreCRCMismatches = YES;
+
     NSString *extractDirectory = [self randomDirectoryWithPrefix:@"ExtractInvalidArchive"];
     NSURL *extractURL = [self.tempDirectory URLByAppendingPathComponent:extractDirectory];
 
@@ -295,13 +290,8 @@ - (void)testExtractFiles_ModifiedCRC_DontIgnoreCRCMismatches
     NSFileManager *fm = [NSFileManager defaultManager];
 
     URKArchive *archive = [[URKArchive alloc] initWithURL:self.testFileURLs[@"Modified CRC Archive.rar"] error:nil];
-
-    BOOL fileHasIntegrity = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return NO;
-    }];
-
-    XCTAssertFalse(fileHasIntegrity);
-
+    archive.ignoreCRCMismatches = YES;
+
     NSString *extractDirectory = [self randomDirectoryWithPrefix:@"ExtractInvalidArchive"];
     NSURL *extractURL = [self.tempDirectory URLByAppendingPathComponent:extractDirectory];
 

Tests/IterateFileInfoTests.m

@@ -230,12 +230,7 @@ - (void)testIterateFileInfo_ModifiedCRC
 - (void)testIterateFileInfo_ModifiedCRC_IgnoringMismatches
 {
     URKArchive *archive = [[URKArchive alloc] initWithURL:self.testFileURLs[@"Modified CRC Archive.rar"] error:nil];
-
-    BOOL checkIntegritySuccess = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return YES;
-    }];
-
-    XCTAssertTrue(checkIntegritySuccess, @"Data integrity check failed for archive with modified CRC, when instructed to ignore");
+    archive.ignoreCRCMismatches = YES;
 
     NSError *error = nil;
     __block int calledCount = 0;

Tests/ListFileInfoTests.m

@@ -199,13 +199,8 @@ - (void)testListFileInfo_ModifiedCRC
 - (void)testListFileInfo_ModifiedCRC_IgnoringMismatches
 {
     URKArchive *archive = [[URKArchive alloc] initWithURL:self.testFileURLs[@"Modified CRC Archive.rar"] error:nil];
-
-    BOOL checkIntegritySuccess = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return YES;
-    }];
-
-    XCTAssertTrue(checkIntegritySuccess, @"Data integrity check failed for archive with modified CRC, when instructed to ignore");
-
+    archive.ignoreCRCMismatches = YES;
+
     NSError *error = nil;
     NSArray<URKFileInfo*> *files = [archive listFileInfo:&error];
 

Tests/ListFilenamesTests.m

@@ -196,12 +196,7 @@ - (void)testListFilenames_ModifiedCRC_IgnoringMismatch
 {
     NSURL *testArchiveURL = self.testFileURLs[@"Modified CRC Archive.rar"];
     URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
-
-    BOOL checkIntegritySuccess = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return YES;
-    }];
-
-    XCTAssertTrue(checkIntegritySuccess, @"Data integrity check failed for archive with modified CRC, when instructed to ignore");
+    archive.ignoreCRCMismatches = YES;
 
     NSError *error = nil;
     NSArray *filesInArchive = [archive listFilenames:&error];

Tests/ListVolumesTests.m

@@ -44,13 +44,8 @@ - (void)testSingleVolume_ModifiedCRC {
 - (void)testSingleVolume_ModifiedCRC_IgnoringMismatch {
     NSURL *testArchiveURL = self.testFileURLs[@"Modified CRC Archive.rar"];
     URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
-
-    BOOL checkIntegritySuccess = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return YES;
-    }];
-
-    XCTAssertTrue(checkIntegritySuccess, @"Data integrity check failed for archive with modified CRC, when instructed to ignore");
-
+    archive.ignoreCRCMismatches = YES;
+
     NSError *listVolumesError = nil;
     NSArray<NSURL*> *volumeURLs = [archive listVolumeURLs:&listVolumesError];
 

Tests/PerformOnDataTests.m

@@ -100,13 +100,8 @@ - (void)testPerformOnData_ModifiedCRC_IgnoringMismatches
 {
     NSURL *testArchiveURL = self.testFileURLs[@"Modified CRC Archive.rar"];
     URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
-
-    BOOL checkIntegritySuccess = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return YES;
-    }];
-
-    XCTAssertTrue(checkIntegritySuccess, @"Data integrity check failed for archive with modified CRC, when instructed to ignore");
-
+    archive.ignoreCRCMismatches = YES;
+
     __block NSUInteger fileIndex = 0;
     NSError *error = nil;
 

Tests/PerformOnFilesTests.m

@@ -68,13 +68,8 @@ - (void)testPerformOnFiles_ModifiedCRC_MismatchesIgnored
     NSURL *testArchiveURL = self.testFileURLs[@"Modified CRC Archive.rar"];
     NSString *password = nil;
     URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL password:password error:nil];
-
-    BOOL checkIntegritySuccess = [archive checkDataIntegrityIgnoringCRCMismatches:^BOOL{
-        return YES;
-    }];
-
-    XCTAssertTrue(checkIntegritySuccess, @"Data integrity check failed for archive with modified CRC, when instructed to ignore");
-
+    archive.ignoreCRCMismatches = YES;
+
     __block NSUInteger fileIndex = 0;
     NSError *error = nil;
 

Tests/URKArchiveTests.m

@@ -34,7 +34,8 @@ - (void)testFileURL {
                                  : self.testFileURLs[testArchiveName]);
 
         URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
-
+        XCTAssertFalse(archive.ignoreCRCMismatches);
+
         NSURL *resolvedURL = archive.fileURL.URLByResolvingSymlinksInPath;
         XCTAssertNotNil(resolvedURL, @"Nil URL returned for valid archive");
         XCTAssertTrue([testArchiveURL isEqual:resolvedURL], @"Resolved URL doesn't match original");
@@ -56,7 +57,8 @@ - (void)testFilename {
                                  : self.testFileURLs[testArchiveName]);
 
         URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
-
+        XCTAssertFalse(archive.ignoreCRCMismatches);
+
         NSString *resolvedFilename = archive.filename;
         XCTAssertNotNil(resolvedFilename, @"Nil filename returned for valid archive");