Encryption/NSFileManager-AES.m at master · darkerk/Encryption · GitHub

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//
//  NSFileManager-AES.m
//  Encryption
//
//  Created by Jeff LaMarche on 2/12/09.
//  Copyright 2009 Jeff LaMarche Consulting. All rights reserved.
//

#import "NSFileManager-AES.h"
#import "rijndael.h"

@implementation NSFileManager(AES)
-(BOOL)AESEncryptFile:(NSString *)inPath toFile:(NSString *)outPath usingPassphrase:(NSString *)pass error:(NSError **)error
{
	unsigned long rk[RKLENGTH(KEYBITS)];
	unsigned char key[KEYLENGTH(KEYBITS)];
	const char *password = [pass UTF8String];

	for (int i = 0; i < sizeof(key); i++)
		key[i] = password != 0 ? *password++ : 0;

	int nrounds = rijndaelSetupEncrypt(rk, key, KEYBITS);
	FILE *fp = fopen([inPath UTF8String], "r");
	FILE *output = fopen([outPath UTF8String], "wb");
	if (output == NULL)
	{
		*error = [NSError errorWithDomain:@"AES Encryption" code:1000 userInfo:[NSDictionary dictionaryWithObject:NSLocalizedString(@"File Open Error", @"File Open Error") forKey:AESEncryptionErrorDescriptionKey]];
		return NO;
	}
    while (1)
	{
		unsigned char plaintext[16];
		unsigned char ciphertext[16];
		int j;
		for (j = 0; j < sizeof(plaintext); j++)
		{
			int c = getc(fp);
			if (c == EOF)
				break;
			plaintext[j] = c;
		}
		if (j == 0)
			break;
		for (; j < sizeof(plaintext); j++)
			plaintext[j] = ' ';
		rijndaelEncrypt(rk, nrounds, plaintext, ciphertext);
		if (fwrite(ciphertext, sizeof(ciphertext), 1, output) != 1)
		{
			fclose(output);
			*error = [NSError errorWithDomain:@"AES Encryption" code:1000 userInfo:[NSDictionary dictionaryWithObject:NSLocalizedString(@"File write error", @"File write error") forKey:AESEncryptionErrorDescriptionKey]];
			return NO;
		}
    }
	fclose(output);
	fclose(fp);
	return YES;
}
-(BOOL)AESDecryptFile:(NSString *)inPath toFile:(NSString *)outPath usingPassphrase:(NSString *)pass error:(NSError **)error
{
	unsigned long rk[RKLENGTH(KEYBITS)];
	unsigned char key[KEYLENGTH(KEYBITS)];
	const char *password = [pass UTF8String];
	for (int i = 0; i < sizeof(key); i++)
		key[i] = password != 0 ? *password++ : 0;

	FILE *fp = fopen([inPath UTF8String], "r");
	FILE *output = fopen([outPath UTF8String], "wb");
	if (output == NULL)
	{
		*error = [NSError errorWithDomain:@"AES Encryption" code:1000 userInfo:[NSDictionary dictionaryWithObject:NSLocalizedString(@"File Open Error", @"File Open Error") forKey:AESEncryptionErrorDescriptionKey]];
		return NO;
	}
	int nrounds = rijndaelSetupDecrypt(rk, key, KEYBITS);
	while (1)
	{
		unsigned char plaintext[16];
		unsigned char ciphertext[16];

		if (fread(ciphertext, sizeof(ciphertext), 1, fp) != 1)
			break;
		rijndaelDecrypt(rk, nrounds, ciphertext, plaintext);
		if (fwrite(plaintext, sizeof(plaintext), 1, output) != 1)
		{
			fclose(output);
			*error = [NSError errorWithDomain:@"AES Encryption" code:1000 userInfo:[NSDictionary dictionaryWithObject:NSLocalizedString(@"File write error", @"File write error") forKey:AESEncryptionErrorDescriptionKey]];
			return NO;
		}
	}
	fclose(output);
	fclose(fp);
	return YES;
}
@end