How to pass an encrypted NSString with stringByAppendingFormat?

Question

I created an as.net web api to receive users credentials to authenticate. In my iOS app I am sending the username and password to the url. I only want to encrypt the password.

How to send an encrypted password that I can then decrypt it in asp.net?

My code:

NSString *username = Username.text;
NSString *password = Password.text;

NSData *dataToEnc = [Password.text dataUsingEncoding:NSUTF8StringEncoding];
NSData *encryptedData = [dataToEnc AES256EncryptWithKey:password];

NSURL *urlFormat = [NSURL URLWithString:[API_LOGIN stringByAppendingFormat:@"%@/%@",username, encryptedData]];
NSMutableURLRequest *urlRequest = [NSMutableURLRequest requestWithURL:urlFormat cachePolicy:NSURLRequestReturnCacheDataElseLoad timeoutInterval:60];
NSData *returnData = [NSURLConnection sendSynchronousRequest:urlRequest returningResponse:nil error:nil];
NSString *responseString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];

This does not work.

Be aware that sending an encrypted password, by itself, is apt to be fairly "weak", security-wise, unless you know what you're doing. — Hot Licks, Nov 24 '14 at 16:35

score 0 · Accepted Answer · answered Nov 24 '14 at 16:23

0

Typically you would base64 encode binary data in an http request.

NSString *encoded = [encryptedData base64EncodedStringWithOptions: NSDataBase64Encoding64CharacterLineLength];

answered Nov 24 '14 at 16:23

KirkSpaziani

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Thank you. It is passing through the URL now. I will try to decode it in my web api c# code and let you know if it worked. – Program_ming Nov 24 '14 at 16:33
Can you please update the code where the encoded string returns without slashes? – Program_ming Nov 24 '14 at 16:53
Do you think it is better to use base32 in this case? – Program_ming Nov 24 '14 at 17:00
Either take a look at this: http://stackoverflow.com/questions/8088473/url-encode-an-nsstring – KirkSpaziani Nov 24 '14 at 17:15
Or consider instead of including the base64encoded data in the URL, pass it in as a header entry. – KirkSpaziani Nov 24 '14 at 17:16

How to pass an encrypted NSString with stringByAppendingFormat?

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