Swift 2.0 NSData(contentsOfURL) always nil in-app but the same code run well in playground [duplicate] - ios

Question

has anyone with the iOS 9 beta 1 had this issue?
I use standard NSURLConnection to connect to a webservice and as soon as a call is made to the webservice i get the below error. This is currently working in iOS 8.3
Possible beta bug? any ideas or thoughts would be great ! I know its very early in iOS 9 development
Here is the full error:
CFNetwork SSLHandshake failed (-9824)
NSURLSession/NSURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9824)
NSURLRequest * urlRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:#"https://mywebserviceurl"]];
NSURLResponse * response = nil;
NSError * error = nil;
NSData * data = [NSURLConnection sendSynchronousRequest:urlRequest
returningResponse:&response
error:&error];

Answer 1

iOS 9 and OSX 10.11 require TLSv1.2 SSL for all hosts you plan to request data from unless you specify exception domains in your app's Info.plist file.
The syntax for the Info.plist configuration looks like this:
<key>NSAppTransportSecurity</key>
<dict>
<key>NSExceptionDomains</key>
<dict>
<key>yourserver.com</key>
<dict>
<!--Include to allow subdomains-->
<key>NSIncludesSubdomains</key>
<true/>
<!--Include to allow insecure HTTP requests-->
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
<!--Include to specify minimum TLS version-->
<key>NSExceptionMinimumTLSVersion</key>
<string>TLSv1.1</string>
</dict>
</dict>
</dict>
If your application (a third-party web browser, for instance) needs to connect to arbitrary hosts, you can configure it like this:
<key>NSAppTransportSecurity</key>
<dict>
<!--Connect to anything (this is probably BAD)-->
<key>NSAllowsArbitraryLoads</key>
<true/>
</dict>
If you're having to do this, it's probably best to update your servers to use TLSv1.2 and SSL, if they're not already doing so. This should be considered a temporary workaround.
As of today, the prerelease documentation makes no mention of any of these configuration options in any specific way. Once it does, I'll update the answer to link to the relevant documentation.

Answer 2

In iOS 10+, the TLS string MUST be of the form "TLSv1.0". It can't just be "1.0". (Sigh)
The following combination of the other Answers works.
Let's say you are trying to connect to a host (YOUR_HOST.COM) that only has TLS 1.0.
Add these to your app's Info.plist
<key>NSAppTransportSecurity</key>
<dict>
<key>NSExceptionDomains</key>
<dict>
<key>YOUR_HOST.COM</key>
<dict>
<key>NSIncludesSubdomains</key>
<true/>
<key>NSTemporaryExceptionAllowsInsecureHTTPLoads</key>
<true/>
<key>NSTemporaryExceptionMinimumTLSVersion</key>
<string>TLSv1.0</string>
<key>NSTemporaryExceptionRequiresForwardSecrecy</key>
<false/>
</dict>
</dict>
</dict>

Answer 3

For more info Configuring App Transport Security Exceptions in iOS 9 and OSX 10.11
Curiously, you’ll notice that the connection attempts to change the
http protocol to https to protect against mistakes in your code where
you may have accidentally misconfigured the URL. In some cases, this
might actually work, but it’s also confusing.
This Shipping an App With App Transport Security covers some good debugging tips
ATS Failure
Most ATS failures will present as CFErrors with a code in the -9800
series. These are defined in the Security/SecureTransport.h header
2015-08-23 06:34:42.700 SelfSignedServerATSTest[3792:683731] NSURLSession/NSURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9813)
CFNETWORK_DIAGNOSTICS
Set the environment variable CFNETWORK_DIAGNOSTICS to 1 in order to
get more information on the console about the failure
nscurl
The tool will run through several different combinations of ATS
exceptions, trying a secure connection to the given host under each
ATS configuration and reporting the result.
nscurl --ats-diagnostics https://example.com

Answer 4

If your backend uses a secure connection ant you get using NSURLSession
CFNetwork SSLHandshake failed (-9801)
NSURLSession/NSURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9801)
you need to check your server configuration especially to get ATS version and SSL certificate Info:
Instead of just Allowing Insecure Connection by setting NSExceptionAllowsInsecureHTTPLoads = YES , instead you need to Allow Lowered Security in case your server do not meet the min requirement (v1.2) for ATS (or better to fix server side).
Allowing Lowered Security to a Single Server
<key>NSExceptionDomains</key>
<dict>
<key>api.yourDomaine.com</key>
<dict>
<key>NSExceptionMinimumTLSVersion</key>
<string>TLSv1.0</string>
<key>NSExceptionRequiresForwardSecrecy</key>
<false/>
</dict>
</dict>
use openssl client to investigate certificate and get your server configuration using openssl client :
openssl s_client -connect api.yourDomaine.com:port //(you may need to specify port or to try with https://... or www.)
..find at the end
SSL-Session:
Protocol : TLSv1
Cipher : AES256-SHA
Session-ID: //
Session-ID-ctx:
Master-Key: //
Key-Arg : None
Start Time: 1449693038
Timeout : 300 (sec)
Verify return code: 0 (ok)
App Transport Security (ATS) require Transport Layer Security (TLS) protocol version 1.2.
Requirements for Connecting Using ATS:
The requirements for a web service connection to use App Transport Security (ATS) involve the server, connection ciphers, and certificates, as follows:
Certificates must be signed with one of the following types of keys:
Secure Hash Algorithm 2 (SHA-2) key with a digest length of at least 256 (that is, SHA-256 or greater)
Elliptic-Curve Cryptography (ECC) key with a size of at least 256 bits
Rivest-Shamir-Adleman (RSA) key with a length of at least 2048 bits An
invalid certificate results in a hard failure and no connection.
The following connection ciphers support forward secrecy (FS) and work
with ATS:
TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
Update: it turns out that openssl only provide the minimal protocol version Protocol : TLSv1 links

Answer 5

After two days of attempts and failures, what worked for me is this code of womble
with One change, according to this post we should stop using sub-keys associated with the NSExceptionDomains dictionary of that kind of Convention
NSTemporaryExceptionMinimumTLSVersion
And use at the new Convention
NSExceptionMinimumTLSVersion
instead.
apple documentation
my code
<key>NSAppTransportSecurity</key>
<dict>
<key>NSExceptionDomains</key>
<dict>
<key>YOUR_HOST.COM</key>
<dict>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
<key>NSExceptionMinimumTLSVersion</key>
<string>TLSv1.0</string>
<key>NSExceptionRequiresForwardSecrecy</key>
<false/>
<key>NSIncludesSubdomains</key>
<true/>
</dict>
</dict>
</dict>

Answer 6

Another useful tool is nmap (brew install nmap)
nmap --script ssl-enum-ciphers -p 443 google.com
Gives output
Starting Nmap 7.12 ( https://nmap.org ) at 2016-08-11 17:25 IDT
Nmap scan report for google.com (172.217.23.46)
Host is up (0.061s latency).
Other addresses for google.com (not scanned): 2a00:1450:4009:80a::200e
PORT STATE SERVICE
443/tcp open https
| ssl-enum-ciphers:
| TLSv1.0:
| ciphers:
| TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA (secp256r1) - A
| TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA (secp256r1) - A
| TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA (secp256r1) - A
| TLS_RSA_WITH_AES_128_CBC_SHA (rsa 2048) - A
| TLS_RSA_WITH_3DES_EDE_CBC_SHA (rsa 2048) - C
| TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA (secp256r1) - A
| TLS_RSA_WITH_AES_256_CBC_SHA (rsa 2048) - A
| compressors:
| NULL
| cipher preference: server
| TLSv1.1:
| ciphers:
| TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA (secp256r1) - A
| TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA (secp256r1) - A
| TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA (secp256r1) - A
| TLS_RSA_WITH_AES_128_CBC_SHA (rsa 2048) - A
| TLS_RSA_WITH_3DES_EDE_CBC_SHA (rsa 2048) - C
| TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA (secp256r1) - A
| TLS_RSA_WITH_AES_256_CBC_SHA (rsa 2048) - A
| compressors:
| NULL
| cipher preference: server
| TLSv1.2:
| ciphers:
| TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA (secp256r1) - A
| TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 (secp256r1) - A
| TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 (secp256r1) - A
| TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA (secp256r1) - A
| TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 (secp256r1) - A
| TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 (secp256r1) - A
| TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 (secp256r1) - A
| TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA (secp256r1) - A
| TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 (secp256r1) - A
| TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (secp256r1) - A
| TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA (secp256r1) - A
| TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 (secp256r1) - A
| TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (secp256r1) - A
| TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 (secp256r1) - A
| TLS_RSA_WITH_3DES_EDE_CBC_SHA (rsa 2048) - C
| TLS_RSA_WITH_AES_128_CBC_SHA (rsa 2048) - A
| TLS_RSA_WITH_AES_128_CBC_SHA256 (rsa 2048) - A
| TLS_RSA_WITH_AES_128_GCM_SHA256 (rsa 2048) - A
| TLS_RSA_WITH_AES_256_CBC_SHA (rsa 2048) - A
| TLS_RSA_WITH_AES_256_CBC_SHA256 (rsa 2048) - A
| TLS_RSA_WITH_AES_256_GCM_SHA384 (rsa 2048) - A
| compressors:
| NULL
| cipher preference: client
|_ least strength: C
Nmap done: 1 IP address (1 host up) scanned in 5.48 seconds

Answer 7

This error was showing up in the logs sometimes when I was using a buggy/crashy Cordova iOS version. It went away when I upgraded or downgraded cordova iOS.
The server I was connecting to was using TLSv1.2 SSL so I knew that was not the problem.

Answer 8

In your project .plist file in add this permission :
<key>NSAppTransportSecurity</key>
<dict>
<!--Connect to anything (this is probably BAD)-->
<key>NSAllowsArbitraryLoads</key>
<true/>
</dict>

Answer 9

The syntax for the Info.plist configuration
<key>NSAppTransportSecurity</key>
<dict>
<key>NSExceptionDomains</key>
<dict>
<key>yourserver.com</key>
<dict>
<!--Include to allow subdomains-->
<key>NSIncludesSubdomains</key>
<true/>
<!--Include to allow insecure HTTP requests-->
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
<!--Include to specify minimum TLS version-->
<key>NSExceptionMinimumTLSVersion</key>
<string>TLSv1.1</string>
</dict>
</dict>

Answer 10

Updated Answer (post-WWDC 2016):
iOS apps will require secure HTTPS connections by the end of
2016. Trying turn ATS off may get your app rejected in the future.
App Transport Security, or ATS, is a feature that Apple introduced in iOS 9. When ATS is enabled, it forces an app to connect to web services over an HTTPS connection rather than non secure HTTP.
However, developers can still switch ATS off and allow their apps to send data over an HTTP connection as mentioned in above answers. At the end of 2016, Apple will make ATS mandatory for all developers who hope to submit their apps to the App Store. link

Answer 11

The device I tested at had wrong time set. So when I tried accessing a page with a certificate that would run out soon it would deny access because the device though the certificate had expired. To fix, set proper time on the device!