iOS 9: Application Transport Security plist configurations - ios

I am currently working on a application that uses both HTTPS endpoints and HTTP endpoints. Now I want to conform to Application Transport Security for iOS9 by making a NSExceptionDomainsdictionary in the plist, but the amount of 3rd party endpoints my application hits is dynamic and always growing so to do this would be a fairly tedious task.
So while I could just set NSAllowsArbitraryLoads to YES I would much rather have ATS off by default except for my handful of secure HTTPS endpoints. Is it possible to do this? I saw one blog post about someone configuring the plist this way.
But I cannot find any information verifying that this is a valid solution, nor do I know how to know if a HTTPS request is using ATS. Does anyone know if this is possible or how to know if this is working?
EDIT
It's worth mention that the tags in the current app documentation is incorrect.
NSExceptionAllowInsecureHTTPLoads
NSExceptionRequiresForwardSecrecy
NSExceptionMinimumTLSVersion
NSThirdPartyExceptionAllowsInsecureHTTPLoads
NSThirdPartyExceptionMinimumTLSVersion
NSThirdPartyExceptionRequiresForwardSecrecy
Are Actually
NSTemporaryExceptionAllowsInsecureHTTPLoads
NSTemporaryExceptionRequiresForwardSecrecy
NSTemporaryExceptionMinimumTLSVersion
NSTemporaryThirdPartyExceptionAllowsInsecureHTTPLoads
NSTemporaryThirdPartyExceptionMinimumTLSVersion
NSTemporaryThirdPartyExceptionRequiresForwardSecrecy

After doing some more research I was able to answer my own question. So basically you are saying everything needs to default to not using ATS by setting NSAllowsArbitraryLoads = YES.
But then in your exceptions dictionary(NSExceptionDomain) you are specifying endpoints that you want to act differently. So that means you can put your HTTPS endpoints in this list and specify it to use ATS by setting NSTemporaryExceptionAllowsInsecureHTTPSLoads to NO. I was able to verify this by putting a unsecure endpoint itunes.apple.com and trying to reach it. When I set NSTemporaryExceptionAllowsInsecureHTTPSLoads to NO it failed and complained about it not being secure.
This may be obvious to most people but with the little documentation out there I hope this helps.

Related

Where I should placed the "coap+tcp" uri?

I'm trying to write CoAP client protocol implementation for embedded device.
Now I'm working on tcp-implementation.
I don't understand where I should placed "coap+tcp" uri in the request.
I'm testing my code with Californium, so that works fine without that uri.
But in the sources of Californium i saw options:
"coap"
"coaps"
"coap+tcp"
"coaps+tcp"
I dont't understand purpose of that.
May anybody explain how to work with that in client-context?
As far as I understand it, URI Scheme is mainly (if consider only technical side) intended for clients to apply the default port if it is not defined:
RFC7252 Section 6.2
All of the requirements listed above for the "coap" scheme are also
requirements for the "coaps" scheme, except that a default UDP port
of 5684 is assumed if the port subcomponent is empty or not given,
and the UDP datagrams MUST be secured through the use of DTLS as
described in Section 9.1.
I've found no any direct mentions in the RFC that the PDU should contain the scheme.

Can I communicate with my server in a way that can't be figured out and spoofed by a third party?

It seems there are a couple choices within Xcode/iOS to communicate with my server, using simple HTTP requests or creating a full blown socket system. What vulnerabilities does each have? My main concern is that I can't allow someone to replicate a call that's not from my app, like you could spoof an AJAX call by examining a webpage's Javascript and getting the address for the call. Obv it wouldn't be so simple with a phone app, but I don't know what's possible for hackers.
Use HTTPS.
Override the TLS chain validation to fail if the public key doesn't match the one stored in your app.
In Apple's TLS validation doc below, start with "Listing 3 Overriding the trust object used by an NSURLConnection object", then add code so that if certificate evaluation succeeds, you check the key inside the challenge's protection space against a known-valid key (or keys) before allowing the connection to proceed.

HTTPS POST Security level

I've searched for this a bit on Stack, but I cannot find a definitive answer for https, only for solutions that somehow include http or unencrypted parameters which are not present in my situation.
I have developed an iOS application that communicates with MySQL via Apache HTTPS POSTS and php.
Now, the server runs with a valid certificate, is only open for traffic on port 443 and all posts are done to https://thedomain.net/obscurefolder/obscurefile.php
If someone knew the correct parameters to post, anyone from anywhere in the world could mess up the database completely, so the question is: Is this method secure? Let it be known nobody has access to the source code and none of the iPads that run this software are jailbreaked or otherwise compromised.
Edit in response to answers:
There are several php files which alone only support one specific operation and depend on very strict input formatting and correct license key (retreived by SQL on every query). They do not respond to input at all unless it's 100% correct and has a proper license (e.g. password) included. There is no actual website, only php files that respond to POSTs, given the correct input, as mentioned above. The webserver has been scanned by a third party security company and contains no known vulnerabilities.
Encryption is necessary but not sufficient for security. There are many other considerations beyond encrypting the connection. With server-side certificates, you can confirm the identity of the server, but you can't (as you are discovering) confirm the identity of the clients (at least not without client-side certficates which are very difficult to protect by virtue of them being on the client).
It sounds like you need to take additional measures to prevent abuse such as:
Only supporting a sane, limited, well-defined set of operations on the database (not passing arbitrary SQL input to your database but instead having a clear, small list of URL handlers that perform specific, reasonable operations on the database).
Validating that the inputs to your handler are reasonable and within allowable parameters.
Authenticating client applications to the best you are able (e.g. with client IDs or other tokens) to restrict the capabilities on a per-client basis and detect anomalous usage patterns for a given client.
Authenticating users to ensure that only authorized users can make the appropriate modifications.
You should also probably get a security expert to review your code and/or hire someone to perform penetration testing on your website to see what vulnerabilities they can uncover.
Sending POST requests is not a secure way of communicating with a server. Inspite of no access to code or valid devices, it still leaves an open way to easily access database and manipulating with it once the link is discovered.
I would not suggest using POST. You can try / use other communication ways if you want to send / fetch data from the server. Encrypting the parameters can also be helpful here though it would increase the code a bit due to encryption-decryption logic.
Its good that your app goes through HTTPS. Make sure the app checks for the certificates during its communication phase.
You can also make use of tokens(Not device tokens) during transactions. This might be a bit complex, but offers more safety.
The solutions and ways here for this are broad. Every possible solution cannot be covered. You might want to try out a few yourself to get an idea. Though I Suggest going for some encryption-decryption on a basic level.
Hope this helps.

CloudFlare SSL compatibility with ASP.NET MVC RequireHttps

I am hosting an ASP.NET MVC 4 site on AppHarbor (which uses Amazon EC2), and I'm using CloudFlare for Flexible SSL. I'm having a problem with redirect loops (310) when trying to use RequireHttps. The problem is that, like EC2, CloudFlare terminates the SSL before forwarding the request onto the server. However, whereas Amazon sets the X-Forwarded-Proto header so that you can handle the request with a custom filter, CloudFlare does not appear to. Or if they do, I don't know how they are doing it, since I can't intercept traffic at that level. I've tried the solutions for Amazon EC2, but they don't seem to help with CloudFlare.
Has anyone experienced this issue, or know enough about CloudFlare to help?
The X-Forwarded-Proto header is intentionally overridden by AppHarbor's load balancers to the actual scheme of the request.
Note that while CloudFlare's flexible SSL option may add slightly more security, there is still unencrypted traffic travelling over the public internet from CloudFlare to AppHarbor. This arguably defies the purpose of SSL for anything else than appearances and reducing the number of attack vectors (like packet sniffing on the user's local network) - i.e. it may look "professional" to your users, but it actually is still insecure.
That's less than ideal particularly since AppHarbor supports both installing your own certificates and includes piggyback SSL out of the box. CloudFlare also recommends using "Full SSL" for scenarios where the origin servers/service support SSL. So you have a couple of options:
Continue to use the insecure "Flexible SSL" option, but instead of inspecting the X-Forwarded-Proto header in your custom RequireHttps filter, you should inspect the scheme attribute of the CF-Visitor header. There are more details in this discussion.
Use "Full SSL" and point CloudFlare to your *.apphb.com hostname. This way you can use the complimentary piggyback SSL that is enabled by default with your AppHarbor app. You'll have to override the Host header on CloudFlare to make this work and here's a blog post on how to do that. This will of course make requests to your app appear like they were made to your *.apphb.com domain - so if for instance you automatically redirect requests to a "canonical" URL or generate absolute URLs you'll likely have to take this into consideration.
Upload your certificate and add a custom hostname to AppHarbor. Then turn on "Full SSL" on CloudFlare. This way the host header will remain the same and your application will continue to work without any modifications. You can read more about the SSL options offered by AppHarbor in this knowledge base article.
This is interesting.
Just I recently had a discussion with one of our clients, who asked me about "flexible" SSL and suggested that we (Incapsula) also offer such option.
After some discussion we both came to the conclusion that such a feature would be misleading, since it will provide the end-user with a false sense of security while also exposing the site owner to liability claims.
Simply put, the visitor on one of "flexible" SSL connection may feel absolutely safe behind the encryption and will be willing provide sensitive data, not knowing that the 'server to cloud' route is not encrypted at all and can be intercepted (i.e. by backdoor shells).
It was interesting to visit here and see others reach the same conclusion. +1
Please know that as website owner you may be liable for any unwanted exposure such setup may cause.
My suggestion is to do the responsible thing and to invest in SSL certificate or even create a self signed one (to use for encryption of 'cloud to server' route).
Or you could just get a free one year SSL cert signed by StartCom and upload that to AppHarbor.
Then you can call it a day and pat yourself on the back! That is until future you one year from now has to purchase a cert =).

Security between app and server?

I know that there are a ton of threads about this. But I'm still confused.
I've got an app that making request to my server(nodeJS) to get JSON-data.
For the moment everyone can get everything at: http://myserver/allUpdates/ with no password. They just have to know the URL.
So I thought I would do it little more secure.
I been looking at Basic Auth, that seems to work by sending username and password in the header for every request.
Is that enough?
Some guys say that it doesn't do much if youre not using SSL. But it must be better than nothing, right?
I've never used SSL and it seems there is a lot to learn.
So my question is, should I bother with auth when I'm not using SSL?
Or are there other alternatives?
Some guys say that it doesn't do much if youre not using SSL. But it must be better than nothing, right?
Unfortunately, those guys are right. Basic Auth is, when sent plaintext, probably worse than nothing as it gives you the vague feeling of some security without any actual security.
This is because it is trivial to intercept network requests through a proxy or similar. If you're not used SSL then every parameter you're sending is easily and readily visible, including your basic authentication credentials.
In answer to your question "should I bother with auth when I'm not using SSL?" - that depends. If you want to ensure your data is only accessed by authenticated users, then it's really SSL or nothing. But if all you're trying to do is reduce the burden on your servers (i.e, rate limiting), then maybe not. I'm going to assume you're looking to do the former, in which case I'd recommend taking the time to get to grips with SSL. There are lots of resources out there about using Node with SSL, depending upon what additional frameworks you might be using (Express, etc).
SSL encrypts your requests, which means that anyone that sniffs your network traffic can't read the payload of the request.
You have two ways to auth the client to the server:
send credentials or an API key with every request OR
login in the client once with credentials or API key and reuse it's session
In both ways, you should use SSL and send the credentials with your POST data.

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