Merge branch 'mkirk/scrub-log-data'

Signal/src/util/OWSScrubbingLogFormatter.m

@@ -10,17 +10,32 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (NSString *)formatLogMessage:(DDLogMessage *)logMessage
 {
-    NSString *string = [super formatLogMessage:logMessage];
+    NSString *logString = [super formatLogMessage:logMessage];
     NSRegularExpression *phoneRegex =
         [NSRegularExpression regularExpressionWithPattern:@"\\+\\d{7,12}(\\d{3})"
                                                   options:NSRegularExpressionCaseInsensitive
                                                     error:nil];
-    NSString *filteredString = [phoneRegex stringByReplacingMatchesInString:string
-                                                                    options:0
-                                                                      range:NSMakeRange(0, [string length])
-                                                               withTemplate:@"[ REDACTED_PHONE_NUMBER:xxx$1 ]"];
 
-    return filteredString;
+    logString = [phoneRegex stringByReplacingMatchesInString:logString
+                                                     options:0
+                                                       range:NSMakeRange(0, [logString length])
+                                                withTemplate:@"[ REDACTED_PHONE_NUMBER:xxx$1 ]"];
+
+
+    // We capture only the first two characters of the hex string for logging.
+    // example log line: "Called someFunction with nsData: <01234567 89abcdef>"
+    //  scrubbed output: "Called someFunction with nsData: [ REDACTED_DATA:01 ]"
+    NSRegularExpression *dataRegex =
+        [NSRegularExpression regularExpressionWithPattern:@"<([\\da-f]{2})[\\da-f]{6}( [\\da-f]{8})*>"
+                                                  options:NSRegularExpressionCaseInsensitive
+                                                    error:nil];
+
+    logString = [dataRegex stringByReplacingMatchesInString:logString
+                                                    options:0
+                                                      range:NSMakeRange(0, [logString length])
+                                               withTemplate:@"[ REDACTED_DATA:$1... ]"];
+
+    return logString;
 }
 
 @end

Signal/test/util/OWSScrubbingLogFormatterTest.m

@@ -27,6 +27,34 @@ NS_ASSUME_NONNULL_BEGIN
                                        timestamp:[NSDate new]];
 }
 
+- (void)testDataScrubbed
+{
+    NSDictionary<NSString *, NSString *> *expectedOutputs = @{
+        @"<01234567 89a23def 23234567 89ab1234>" : @"[ REDACTED_DATA:01... ]",
+        @"My data is: <01234567 89a23def 23234567 89ab1223>" : @"My data is: [ REDACTED_DATA:01... ]",
+        @"My data is <12345670 89a23def 23234567 89ab1223> their data is <87654321 89ab1234>" :
+            @"My data is [ REDACTED_DATA:12... ] their data is [ REDACTED_DATA:87... ]"
+    };
+
+    OWSScrubbingLogFormatter *formatter = [OWSScrubbingLogFormatter new];
+
+    // Other formatters add a dynamic date prefix to log lines. We truncate that when comparing our expected output.
+    NSUInteger datePrefixLength = [formatter formatLogMessage:[self messageWithString:@""]].length;
+
+    for (NSString *input in expectedOutputs) {
+
+        NSString *rawActual = [formatter formatLogMessage:[self messageWithString:input]];
+
+        // strip out dynamic date portion of log line
+        NSString *actual =
+            [rawActual substringWithRange:NSMakeRange(datePrefixLength, rawActual.length - datePrefixLength)];
+
+        NSString *expected = expectedOutputs[input];
+
+        XCTAssertEqualObjects(expected, actual);
+    }
+}
+
 - (void)testPhoneNumbersScrubbed
 {
     NSArray<NSString *> *phoneStrings = @[