I state that I am not an expert.
I'm trying to create a TCP server / client encrypted. I have implemented SSL, and I created a key selfsigned and its certificate.
I realized, thanks to many post also read on this site that i do not need to use the certificate. I refer in particular to a user's response Remy Lebeau: Delphi Indy - How to get SSL certificates for a SSL-TCP Client/Server link with Indy 10
Now I was wondering if you can, somehow, prevent attacks man in the middle.
Or rather, if I implement the code of the app the signature and fingerprint of the certificate and verify during event OnVerifyPeer is enough?
Related
How do I install a certified TLS certificate on an iOS app?
I assume there also needs to be the ability to send a new certificate over the network to the app in the future, if need be, and how exactly would that work?
I assume once it's installed that Apple will handle the entire handshake process of the device side?
Had some trouble finding explicit answers to these questions online.
Assuming that what you are describing is a signed SSL certificate for your domain name, the only thing you will need to do is install it on your web server. When your application makes a request to your web server, the server will send the certificate to the client during the initial HTTPS handshake, and the client will verify it automatically.
I'm building multi-platform client app using FireMonkey which will communicate with server that will be also developed in house, so we were looking for using self signed certificate in this scenario.
According to this article: SSL / HTTPS on different platforms with TIdHTTP and TRESTClient, it seems that TRestClient has support for SSL out of the box and there is no need to assign IO Handler like with TidHTTP. Problem is that I can't find a way to assign self signed certificate to TRestClient the way you could do it with IdSSLIOHandlerSocketOpenSSL component. Also, TRestClient.HTTPClient seems to not have published IOHandler property the way Indy's HTTP had.
My question is this:
Is there a way to provide self-signed certificate to TRestClient component in Delphi XE7 and how?
I'm fairly new to SSL and secure connections in general. What are the major steps required for an iOS app to talk to a server over a secure communications channel?
I'm aware that an SSL certificate will probably be necessary. I'm planning to purchase one from a trusted certificate authority. However I'm not sure if both the app and the server need certificates or if it's just the server. Also I'm not sure how to handle SSL errors. Perhaps there's a library that can help with this like ASIHTTPRequest or similar.
If you are using HTTPS as your protocol for communication and have valid certificates on your server all that should be required is changing your http:// to https:// on your client. For HTTP libraries a very popular option now is AFNetworking. It is a bit better maintained than ASI and has some nice block features not supported by ASI.
As far as SSL errors, it is usually a good idea to present the warnings to end users (through alert views or some other means). They could point to real security attacks (but more likely will point to miss configured or expired certificates).
The Application i am working on needs to connect to a webservice over https, The certificate is trusted and valid.
I have used NSURLConnection is previous projects to use soap over http
Can anybody please point the difference between the two above mentioned scenarios,
I also need to understand what exactly happens when connecting over https, is the certificate stored automatically on the device, how does ssl handshake happen.
Any Pointers in this direction will be really helpful.
Regards,
Ishan
I need some clarification. Is the certificate signed by Apple for use with notifications or is it signed by an SSL root certificate authority (like VeriSign)?
Apple signed certificates are only to be used with WebServer to Apple Server communications like the Apple Push Notification Service. They are not intended for iOS device to WebServer.
A SSL certificate signed by a SSL root certificate authority should just work.
I think you are looking for an HTTP over SSL/TLS primer. So, here it goes.
HTTP is an unencrypted channel. The request and response are in a plain text data stream. HTTPS is an encrypted channel. The request and response are in a data stream encrypted using a shared master key. The magic of SSL/TLS is how this encrypted channel is created.
First, the client and server say hello to each other (in a clear channel).
Next, the client downloads the server's public certificate (in a clear channel).
At this point, the client has some work to do. It needs to verify the certificate. It needs to know that it understands the certificate, that the date range is valid, that the certificate is signed by a trusted certificate authority, and that the certificate has not been revoked.
Now, the client knows that it can trust the server.
Next, It sends a few short messages encrypted with the public key of the server (which is in the server's public certificate). These messages can only be decrypted by the server's private key (which only the server knows about). These messages allow the client and the server to negotiate a master key.
Finally, the client and the server begin the normal HTTP request and response using the newly created encrypted channel.
I hope this is what you are looking for. For a more detailed description see: http://www.moserware.com/2009/06/first-few-milliseconds-of-https.html
If the certificate was issued by a chain of certificate authorities whose root is trusted by Apple, then there is nothing to do. The iOS device will accept the certificate, as long as it is otherwise valid (ie not expired, not revoked, etc).
If the CA chain's root is not trusted by Apple, you will need to download the root's certificate to the phone. This can be done (I think) via the iPhone Configuration Utility. Enterprise provisioning scenarios undoubtedly support this also.
I'm working on an ios application without authentication. Now I would like to protect my server API from calls other then my ios application. A possible solution would be to have the application generate a unique key (based on the appname and the signing), which is not stored on the device since this is the main problem. I could think off an application logic that does some protection combined with some file encryption but the problem is that somewhere something is stored (ex public key can be stored in keychain but still not safe for my API-hackers).
Anyone any tips/advice on how I can handle this ?
thanks in advance
In short, there is no 100% secure way to make sure that the request comes from your application, if the key is available to the iPhone, it's available to extract from the iPhone.
You can make it reasonably safe by calculating a key runtime from info in the application as you say and communicate it over SSL, but a determined attacker can always reverse engineer the key generation too.
What you want to do is employ mutually-authenticated SSL, so that your server will only accept incoming connections from your app and your app will only communicate with your server.
Here's the high-level approach. Create a self-signed server SSL certificate and deploy on your web server. You can use freely available tools for this, like keytool, and I think (but don't know for sure) that Apple includes a tool for this with the iOS SDK. Then create a self-signed client and deploy that within your application in a custom keystore included in your application as a resource. Configure the server to require client-side SSL authentication and to only accept the client certificate you generated. Configure the client to use that client-side certificate to identify itself and only accept the one server-side certificate you installed on your server for that part of it.
If someone/something other than your app attempts to connect to your server, the SSL connection will not be created, as the server will reject incoming SSL connections that do not present the client certificate that you have included in your app.