key file to database file mapping now hash the database url to obscure the mapping

MacPass/NSString+MPHash.m

@@ -0,0 +1,34 @@
+//
+//  NSString+MPHash.m
+//  MacPass
+//
+//  Created by Michael Starke on 05/02/16.
+//  Copyright © 2016 HicknHack Software GmbH. All rights reserved.
+//
+
+#import "NSString+MPHash.h"
+
+#import <CommonCrypto/CommonCrypto.h>
+
+@implementation NSString (MPHash)
+
++ (NSString*)sha1HexDigest:(NSString*)input {
+  if(input.length == 0) {
+    return nil;
+  }
+  const char* str = input.UTF8String;
+  unsigned char result[CC_SHA1_DIGEST_LENGTH];
+  CC_SHA1(str, (CC_LONG)strlen(str), result);
+  
+  NSMutableString *hexDigest = [NSMutableString stringWithCapacity:CC_SHA1_DIGEST_LENGTH*2];
+  for(int i = 0; i<CC_SHA1_DIGEST_LENGTH; i++) {
+    [hexDigest appendFormat:@"%02x",result[i]];
+  }
+  return hexDigest;
+}
+
+- (NSString *)sha1HexDigest {
+  return [NSString sha1HexDigest:self];
+}
+
+@end