Add methods to check data integrity

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 * Added support for `NSProgress` and `NSProgressReporting` in all extraction and iteration methods (Issue #34)
 * Added enhanced support for multivolume archives (PRs #59, #38 - Thanks to [@aonez](https://github.com/aonez) for the idea and implementation!)
+* Added methods for checking data integrity of archived files (Issue #26, PR #61 - Thanks to [@amosavian](https://github.com/amosavian) for the suggestion!)
 * Added detailed logging using new unified logging framework. See [the readme](README.md) for more details (Issue #35)
 * Added localized details to returned `NSError` objects (Issue #45)
 * Moved `unrar` sources into a static library, and addressed a wide variety of warnings exposed by the `-Weverything` flag (Issue #56)

Classes/URKArchive.h

@@ -326,7 +326,7 @@ extern NSString *URKErrorDomain;
 - (BOOL)extractFilesTo:(NSString *)filePath
              overwrite:(BOOL)overwrite
               progress:(nullable void (^)(URKFileInfo *currentFile, CGFloat percentArchiveDecompressed))progressBlock
-                 error:(NSError **)error __deprecated_msg("Use extractFilesTo:overwrite:error: instead, and if using the progress block, replace with NSProgress as described in the README");
+                 error:(NSError **)error __deprecated_msg("Use -extractFilesTo:overwrite:error: instead, and if using the progress block, replace with NSProgress as described in the README");
 
 /**
  *  Unarchive a single file from the archive into memory. Supports NSProgress for progress reporting, which also
@@ -354,7 +354,7 @@ extern NSString *URKErrorDomain;
  */
 - (nullable NSData *)extractData:(URKFileInfo *)fileInfo
                         progress:(nullable void (^)(CGFloat percentDecompressed))progressBlock
-                           error:(NSError **)error __deprecated_msg("Use extractData:error: instead, and if using the progress block, replace with NSProgress as described in the README");
+                           error:(NSError **)error __deprecated_msg("Use -extractData:error: instead, and if using the progress block, replace with NSProgress as described in the README");
 
 /**
  *  Unarchive a single file from the archive into memory. Supports NSProgress for progress reporting, which also
@@ -385,7 +385,7 @@ extern NSString *URKErrorDomain;
  */
 - (nullable NSData *)extractDataFromFile:(NSString *)filePath
                                 progress:(nullable void (^)(CGFloat percentDecompressed))progressBlock
-                                   error:(NSError **)error __deprecated_msg("Use extractDataFromFile:error: instead, and if using the progress block, replace with NSProgress as described in the README");
+                                   error:(NSError **)error __deprecated_msg("Use -extractDataFromFile:error: instead, and if using the progress block, replace with NSProgress as described in the README");
 
 /**
  *  Loops through each file in the archive in alphabetical order, allowing you to perform an
@@ -452,5 +452,24 @@ 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
+
+ @return YES if the data is all correct, false if any check failed
+ */
+- (BOOL)checkDataIntegrity;
+
+
+/**
+ Extract 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
+
+ @return YES if the data is correct, false if any check failed
+ */
+- (BOOL)checkDataIntegrityOfFile:(NSString *)filePath;
+
 @end
 NS_ASSUME_NONNULL_END

Classes/URKArchive.mm

@@ -9,6 +9,8 @@
 #import "UnrarKitMacros.h"
 #import "NSString+UnrarKit.h"
 
+#import "zlib.h"
+
 RarHppIgnore
 #import "rar.hpp"
 #pragma clang diagnostic pop
@@ -721,6 +723,11 @@ - (BOOL)performOnFilesInArchive:(void(^)(URKFileInfo *fileInfo, BOOL *stop))acti
         URKCreateActivity("Iterating Each File Info");
 
         [sortedFileInfo enumerateObjectsUsingBlock:^(URKFileInfo *info, NSUInteger idx, BOOL *stop) {
+            if (progress.isCancelled) {
+                URKLogInfo("PerformOnFiles iteration was cancelled");
+                *stop = YES;
+            }
+
             URKLogDebug("Performing action on %{public}@", info.filename);
             action(info, stop);
             progress.completedUnitCount += 1;
@@ -729,11 +736,6 @@ - (BOOL)performOnFilesInArchive:(void(^)(URKFileInfo *fileInfo, BOOL *stop))acti
                 URKLogInfo("Action dictated an early stop");
                 progress.completedUnitCount = progress.totalUnitCount;
             }
-
-            if (progress.isCancelled) {
-                URKLogInfo("File info iteration was cancelled");
-                *stop = YES;
-            }
         }];
     }
 
@@ -1030,6 +1032,53 @@ - (BOOL)validatePassword
     return passwordIsGood;
 }
 
+- (BOOL)checkDataIntegrity
+{
+    return [self checkDataIntegrityOfFile:(NSString *_Nonnull)nil];
+}
+
+- (BOOL)checkDataIntegrityOfFile:(NSString *)filePath
+{
+    URKCreateActivity("Checking Data Integrity");
+
+    URKLogInfo("Checking integrity of %{public}@", filePath ? filePath : @"whole archive");
+
+    __block BOOL corruptDataFound = YES;
+
+    NSError *performOnFilesError = nil;
+    [self performOnFilesInArchive:^(URKFileInfo *fileInfo, BOOL *stop) {
+        URKCreateActivity("Iterating through each file");
+        corruptDataFound = NO; // Set inside here so invalid archives are marked as corrupt
+        if (filePath && ![fileInfo.filename isEqualToString:filePath]) return;
+
+        URKLogDebug("Extracting '%{public}@ to check its CRC...", fileInfo.filename);
+        NSError *extractError = nil;
+        NSData *fileData = [self extractData:fileInfo error:&extractError];
+        if (!fileData) {
+            URKLogError("Error extracting %{public}@: %{public}@", fileInfo.filename, extractError);
+            *stop = YES;
+            return;
+        }
+
+        uLong expectedCRC = fileInfo.CRC;
+        uLong actualCRC = crc32((uLong)0, (const Bytef*)fileData.bytes, (uint)fileData.length);
+        URKLogDebug("Checking integrity of %{public}@. Expected CRC: %010lu vs. Actual: %010lu",
+                    fileInfo.filename, expectedCRC, actualCRC);
+        if (expectedCRC != actualCRC) {
+            corruptDataFound = YES;
+            URKLogError("Corrupt data found (filename: %{public}@, expected CRC: %010lu, actual CRC: %010lu",
+                        fileInfo.filename, expectedCRC, actualCRC);
+        }
+
+        if (filePath) *stop = YES;
+    } error:&performOnFilesError];
+
+    if (performOnFilesError) {
+        URKLogError("Error checking data integrity: %{public}@", performOnFilesError);
+    }
+
+    return !corruptDataFound;
+}
 
 
 #pragma mark - Callback Functions
@@ -1278,7 +1327,7 @@ - (NSString *)errorNameForErrorCode:(NSInteger)errorCode detail:(NSString * __au
         case URKErrorCodeUserCancelled:
             errorName = @"ERAR_USER_CANCELLED";
             detail = NSLocalizedStringFromTableInBundle(@"User cancelled the operation in progress", @"UnrarKit", _resources, @"Error detail string");
-   break;
+            break;
 
         default:
             errorName = [NSString stringWithFormat:@"Unknown (%ld)", (long)errorCode];
@@ -1292,12 +1341,17 @@ - (NSString *)errorNameForErrorCode:(NSInteger)errorCode detail:(NSString * __au
 
 - (BOOL)assignError:(NSError * __autoreleasing *)error code:(NSInteger)errorCode errorName:(NSString * __autoreleasing *)outErrorName
 {
-    if (error) {
-        NSAssert(outErrorName, @"An out variable for errorName must be provided");
-
-        NSString *errorDetail = nil;
-        *outErrorName = [self errorNameForErrorCode:errorCode detail:&errorDetail];
+    return [self assignError:error code:errorCode underlyer:nil errorName:outErrorName];
+}
+
+- (BOOL)assignError:(NSError * __autoreleasing *)error code:(NSInteger)errorCode underlyer:(NSError *)underlyingError errorName:(NSString * __autoreleasing *)outErrorName
+{
+    NSAssert(outErrorName, @"An out variable for errorName must be provided");
+
+    NSString *errorDetail = nil;
+    *outErrorName = [self errorNameForErrorCode:errorCode detail:&errorDetail];
 
+    if (error) {
         NSMutableDictionary *userInfo = [NSMutableDictionary dictionaryWithDictionary:
                                          @{NSLocalizedFailureReasonErrorKey: *outErrorName,
                                            NSLocalizedDescriptionKey: errorDetail,
@@ -1307,6 +1361,10 @@ - (BOOL)assignError:(NSError * __autoreleasing *)error code:(NSInteger)errorCode
             userInfo[NSURLErrorKey] = self.fileURL;
         }
 
+        if (underlyingError) {
+            userInfo[NSUnderlyingErrorKey] = underlyingError;
+        }
+
         *error = [NSError errorWithDomain:URKErrorDomain
                                      code:errorCode
                                  userInfo:userInfo];
@@ -1337,6 +1395,8 @@ - (NSProgress *)beginProgressOperation:(unsigned long long)totalUnitCount
 
     NSProgress *progress;
     progress = self.progress;
+    self.progress = nil;
+
     if (!progress) {
         progress = [[NSProgress alloc] initWithParent:[NSProgress currentProgress]
                                              userInfo:nil];

README.md

@@ -61,19 +61,12 @@ if (archive.isPasswordProtected) {
 ```Objective-C
 BOOL extractFilesSuccessful = [archive extractFilesTo:@"some/directory"
                                             overWrite:NO
-                                             progress:
-    ^(URKFileInfo *currentFile, CGFloat percentArchiveDecompressed) {
-        NSLog(@"Extracting %@: %f%% complete", currentFile.filename, percentArchiveDecompressed);
-    }
                                                 error:&error];
 ```
 
 ## Extracting a file into memory
 ```Objective-C
 NSData *extractedData = [archive extractDataFromFile:@"a file in the archive.jpg"
-                                            progress:^(CGFloat percentDecompressed) {
-                                                         NSLog(@"Extracting, %f%% complete", percentDecompressed);
-                                            }
                                                error:&error];
 ```
 

Tests/CheckDataTests.m

@@ -0,0 +1,94 @@
+//
+//  CheckDataTests.m
+//  UnrarKit
+//
+//  Created by Dov Frankel on 10/6/17.
+//
+
+#import "URKArchiveTestCase.h"
+
+@interface CheckDataTests : URKArchiveTestCase @end
+
+@implementation CheckDataTests
+
+#pragma mark - checkDataIntegrity
+
+- (void)testCheckDataIntegrity {
+    NSArray *testArchives = @[@"Test Archive.rar",
+                              @"Test Archive (Password).rar",
+                              @"Test Archive (Header Password).rar"];
+
+    for (NSString *testArchiveName in testArchives) {
+        NSLog(@"Testing data integrity of archive %@", testArchiveName);
+        NSURL *testArchiveURL = self.testFileURLs[testArchiveName];
+        NSString *password = ([testArchiveName rangeOfString:@"Password"].location != NSNotFound
+                              ? @"password"
+                              : nil);
+        URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL password:password error:nil];
+
+        BOOL success = [archive checkDataIntegrity];
+        XCTAssertTrue(success, @"Data integrity check failed for %@", testArchiveName);
+    }
+}
+
+- (void)testCheckDataIntegrity_NotAnArchive {
+    NSURL *testArchiveURL = self.testFileURLs[@"Test File B.jpg"];
+    URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
+
+    BOOL success = [archive checkDataIntegrity];
+    XCTAssertFalse(success, @"Data integrity check passed for non-archive");
+}
+
+- (void)testCheckDataIntegrity_ModifiedCRC {
+    NSURL *testArchiveURL = self.testFileURLs[@"Modified CRC Archive.rar"];
+    URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
+
+    BOOL success = [archive checkDataIntegrity];
+    XCTAssertFalse(success, @"Data integrity check passed for archive with a modified CRC");
+}
+
+#pragma mark - checkDataIntegrityOfFile
+
+- (void)testCheckDataIntegrityForFile {
+    NSArray *testArchives = @[@"Test Archive.rar",
+                              @"Test Archive (Password).rar",
+                              @"Test Archive (Header Password).rar"];
+
+    for (NSString *testArchiveName in testArchives) {
+        NSLog(@"Testing data integrity of file in archive %@", testArchiveName);
+        NSURL *testArchiveURL = self.testFileURLs[testArchiveName];
+        NSString *password = ([testArchiveName rangeOfString:@"Password"].location != NSNotFound
+                              ? @"password"
+                              : nil);
+        URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL password:password error:nil];
+
+        NSError *listFilenamesError = nil;
+        NSArray <NSString*> *filenames = [archive listFilenames:&listFilenamesError];
+
+        XCTAssertNotNil(filenames, @"No file info returned for %@", testArchiveName);
+        XCTAssertNil(listFilenamesError, @"Error returned for %@: %@", testArchiveName, listFilenamesError);
+
+        NSString *firstFilename = filenames.firstObject;
+        BOOL success = [archive checkDataIntegrityOfFile:firstFilename];
+
+        XCTAssertTrue(success, @"Data integrity check failed for %@ in %@", firstFilename, testArchiveName);
+    }
+}
+
+- (void)testCheckDataIntegrityForFile_NotAnArchive {
+    NSURL *testArchiveURL = self.testFileURLs[@"Test File B.jpg"];
+    URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
+
+    BOOL success = [archive checkDataIntegrityOfFile:@"README.md"];
+    XCTAssertFalse(success, @"Data integrity check passed for non-archive");
+}
+
+- (void)testCheckDataIntegrityForFile_ModifiedCRC {
+    NSURL *testArchiveURL = self.testFileURLs[@"Modified CRC Archive.rar"];
+    URKArchive *archive = [[URKArchive alloc] initWithURL:testArchiveURL error:nil];
+
+    BOOL success = [archive checkDataIntegrityOfFile:@"README.md"];
+    XCTAssertFalse(success, @"Data integrity check passed for archive with modified CRC");
+}
+
+@end

Tests/ProgressReportingTests.m

@@ -64,7 +64,7 @@ - (void)testProgressReporting_ExtractFiles_FractionCompleted
                                  overwrite:NO
                                      error:&extractError];
 
-    XCTAssertNil(extractError, @"Error returned by extractFilesTo:overwrite:progress:error:");
+    XCTAssertNil(extractError, @"Error returned by extractFilesTo:overwrite:error:");
     XCTAssertTrue(success, @"Unrar failed to extract %@ to %@", testArchiveName, extractURL);
 
     [extractFilesProgress resignCurrent];
@@ -113,7 +113,7 @@ - (void)testProgressReporting_ExtractFiles_Description
                                  overwrite:NO
                                      error:&extractError];
 
-    XCTAssertNil(extractError, @"Error returned by extractFilesTo:overwrite:progress:error:");
+    XCTAssertNil(extractError, @"Error returned by extractFilesTo:overwrite:error:");
     XCTAssertTrue(success, @"Unrar failed to extract %@ to %@", testArchiveName, extractURL);
 
     [extractFilesProgress removeObserver:self forKeyPath:observedSelector];
@@ -153,7 +153,7 @@ - (void)testProgressReporting_ExtractFiles_AdditionalDescription
                                  overwrite:NO
                                      error:&extractError];
 
-    XCTAssertNil(extractError, @"Error returned by extractFilesTo:overwrite:progress:error:");
+    XCTAssertNil(extractError, @"Error returned by extractFilesTo:overwrite:error:");
     XCTAssertTrue(success, @"Unrar failed to extract %@ to %@", testArchiveName, extractURL);
 
     [extractFilesProgress removeObserver:self forKeyPath:observedSelector];
@@ -194,7 +194,7 @@ - (void)testProgressReporting_ExtractFiles_FileInfo
                                  overwrite:NO
                                      error:&extractError];
 
-    XCTAssertNil(extractError, @"Error returned by extractFilesTo:overwrite:progress:error:");
+    XCTAssertNil(extractError, @"Error returned by extractFilesTo:overwrite:error:");
     XCTAssertTrue(success, @"Unrar failed to extract %@ to %@", testArchiveName, extractURL);
 
     [extractFilesProgress removeObserver:self forKeyPath:observedSelector];
@@ -321,7 +321,7 @@ - (void)testProgressCancellation_ExtractFiles {
                                  overwrite:NO
                                      error:&extractError];
 
-    XCTAssertNotNil(extractError, @"Error not returned by extractFilesTo:overwrite:progress:error:");
+    XCTAssertNotNil(extractError, @"Error not returned by extractFilesTo:overwrite:error:");
     XCTAssertEqual(extractError.code, URKErrorCodeUserCancelled, @"Incorrect error code returned from user cancellation");
     XCTAssertFalse(success, @"Unrar didn't cancel extraction");
 
@@ -365,7 +365,7 @@ - (void)testProgressReporting_ExtractData {
     NSError *extractError = nil;
     NSData *data = [archive extractDataFromFile:firstFile error:&extractError];
 
-    XCTAssertNil(extractError, @"Error returned by extractDataFromFile:progress:error:");
+    XCTAssertNil(extractError, @"Error returned by extractDataFromFile:error:");
     XCTAssertNotNil(data, @"Unrar failed to extract large archive");
 
     [extractFileProgress resignCurrent];
@@ -409,7 +409,7 @@ - (void)testProgressReporting_ExtractBufferedData {
                                                   error:&extractError
                                                  action:^(NSData * _Nonnull dataChunk, CGFloat percentDecompressed) {}];
 
-    XCTAssertNil(extractError, @"Error returned by extractDataFromFile:progress:error:");
+    XCTAssertNil(extractError, @"Error returned by extractDataFromFile:error:");
     XCTAssertTrue(success, @"Unrar failed to extract large archive into buffer");
 
     [extractFileProgress resignCurrent];
@@ -451,7 +451,7 @@ - (void)testProgressCancellation_ExtractData {
     NSError *extractError = nil;
     NSData *data = [archive extractDataFromFile:firstFile error:&extractError];
 
-    XCTAssertNotNil(extractError, @"No error returned by cancelled extractDataFromFile:progress:error:");
+    XCTAssertNotNil(extractError, @"No error returned by cancelled extractDataFromFile:error:");
     XCTAssertEqual(extractError.code, URKErrorCodeUserCancelled, @"Incorrect error code returned from user cancellation");
     XCTAssertNil(data, @"extractData didn't return nil when cancelled");
 
@@ -487,7 +487,7 @@ - (void)testProgressCancellation_ExtractBufferedData {
                                                      blockCallCount++;
                                                  }];
 
-    XCTAssertNotNil(extractError, @"No error returned by cancelled extractDataFromFile:progress:error:");
+    XCTAssertNotNil(extractError, @"No error returned by cancelled extractDataFromFile:error:");
     XCTAssertEqual(extractError.code, URKErrorCodeUserCancelled, @"Incorrect error code returned from user cancellation");
     XCTAssertFalse(success, @"extractBufferedData didn't return false when cancelled");