I am trying to set up self signed SSL certificate for my IOS app which has a REST backend.
My question is should I use [securityPolicy setAllowInvalidCertificates:YES]; when we use self signed certificates? And NO with trusted certificates?
I didn't understand the exact mechanism however I read about SSL for hours.. It works with setAllowInvalidCertificates:YES but otherwise I get 1012 error.
Yes, you should set [securityPolicy setAllowInvalidCertificates:YES]; when using self signed certificates. And correct; you should use NO with trusted certificates.
You are likely still getting the error when it is set to NO because a part of your certificate chain is not trusted. Try using an app called SSL Detective to make sure the entire chain is trusted with no red (untrusted) components. AFNetworking doesn't like those.
My question is should I use [securityPolicy setAllowInvalidCertificates:YES]; when we use self signed certificates? And NO with trusted certificates?
No! This would defeat the whole purpose of SSL because it would make man-in-the-middle attacks possible. Better use public key pinning. I don't know how to do this with AFNetwork, but the linked resource has code for lots of environments.
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I am developing an app with a server part programmed in Go and a client programmed in C#, the connection between the two is made using TCP socket communication, and to ensure the connection I am using TLS.
My question is whether there would be any security problem in my case when using self-signed certificates for TLS communication.
I understand that for a web server that uses https it is necessary to use certificates signed by a certificate authority (CA) but in my case, when connecting my own client application I don't see why I should use one of these.
If anyone knows anything about it, it would be a great help.
Certificates are used for authenticating the end points, and usually the cert is signed by a certificate authority which your client (such as a web browser) already trusts. Using a self-signed cert in that scenario can lead to problems, as the browser won't trust it, and so will pop a warning box. However, the real issue is that for the typical user, a warning from your server is as good as indistinguishable from an attacker using another self-signed certificate. They'll click-away and KABOOM!
If this is a closed environment, and you control both the server and client, then the self-signed certificate is irrelevant. In fact, you don't even need one at all, and may be better off with one of the alternatives, like TLS-PSK, or TLS-SRP.
I have to develop a web application that is both secured over https and uses client authentication certificates. The clients are connecting via invitation, thus it is not intended for users stumbling upon this application by googling around.
The ideal would be to get an intermediate CA certificate form a public root authority and sign both the ssl certificate and use it to issue client authentication certificates. I think that won't work, as simply put I will never qualify for such an intermediate CA (as far as I know, but maybe I am wrong with that).
Second guess: create own Root CA, an intermediate CA and use them. Because of what I wrote about the users, I can embed the necessary certificate chain in the issued certificates. This technically works.
What I would prefer is to get an ssl certificate from public authority and to use my own chain to issue authentication certificates and verify the users. According to this it is possible. But I haven't found anything about how to configure IIS for example (or Kestrel) to request client certificates issued by a specific CA, even less some standard specification where this flow is described.
Basically our iOS app needs to communicate with a server which has a self signed certificate for now. In my app, the https is failing with untrusted server certificate which is understandable. The error is like this:
Error Domain=NSURLErrorDomain Code=-1202 "The certificate for this server is invalid. You might be connecting to a server that is pretending to be “my host name here” which could put your confidential information at risk."
So I sent the self signed certificate via email to the iOS device and imported into the profiles and hoping that it would be used as part of root CA for https authentication. To my surprise, it is not and I am still getting the same error. I think that iOS would be default to use root CAs at keychain to validate the server certificate and from what I read, the imported certificate at profiles are at keychain as well. So I could not understand why my imported self signed certificate is not used as root CA.
At this point, I don't really want to trust this self signed certificate via the coding like this iOS authenticate HTTPS with self-signed certificate or In iOS, how to connect to a server using https with self-signed certificate on the server? since this won't work in customer case where they would install our server on their network and they could create their own self signed certificate.
Somehow I didn't really get much information around this from searching. Could anyone shed some lights here and what I need to do to debug this? Thanks very much.
Update on July 15:
More update around this. I also tried to use configuration profile to add a self signed CA to root CA at the iOS device by following Adding Trusted Root Certificate Authorities to iOS , from my testing on 6.0 iPad and iPhone, it doesn't work as well. So not sure if that only works on jail broken device or not. In the end, I end up by allowing user to import a self signed certificate into the app. The app would load such imported certificate for certificate verification similar to this In iOS, how to connect to a server using https with self-signed certificate on the server?. Hope that it would help others in this case.
looking at the first tutorial you linked to you should be able to use that or some more advanced form of that and once you have tested and have it working then all you have to do for a client to create and add their own certificate would be to override/replace the localhost.cer file in the apps folder where the file localhost.cer "or whatever name scheme you use" is located. there are many ways to do this but one could be telling the app a link where the certificate is online for download and once downloaded, then replace.
Any questions I'll try and help further but hopes this helps you in the right direction.
I have a mobile app that will be communicating with my webserver over https. My question is, do I even need to worry about installing a certificate since all traffic to this api will be headless?
In my understanding, SSL provides the encryption for a request, and a certificate establishes trust for the end user. Because these calls to my webserver will essentially be headless, I'm thinking I don't need to worry about the trust establishment.
Am I correct in this thinking?
You will either need a self-signed certificate or a CA-signed certificate in order to use HTTPS on your server.
If your certificate is not assigned to you by a certificate authority, then any connection you make will trigger an error in your URLRequest that you will have to handle. The problem with an untrusted certificate is that a malicious man-in-the-middle could fake data to and from your server with his own self-signed certificate, and possibly pick up authentication credentials or data that he should not have access to.
If you are dealing with any authentication credentials or other private data, I'd recommend just requesting a signed certificate. If you shop around, you can find cheap signed certificates for $10-20 a year, which is a trivial cost to protect your users.
However, if this is just a personal project (the only data you have to worry about is yours), or any data that you will be sending is freely available, a self-signed certificate may be enough.
My application uses ASIHttpRequest for my server communication. I have a requirement that I should block HTTP protocol cos I dont wont to transmit that data over insecure link. So only SSL over HTTPS will be allowed. Also even thought the link is HTTPS I need to ensure that I am calling to the correct certificate. So I need a server certificate validation in my code. Please guide me how to do this.
I researched on this. I found few possible answers. One is to create a client certificate and do the validation. Also there are ways to "Client certificates support" under ASIHttpRequest documentation. So how to achieve my requirements above. Also integration of CFNetwork code into ASIHttpRequest will also do.
Regards,
Dilshan
You can get a validated certificate from an certificate authority like StartSSL or Thawte. Then iOS checks if the certificate is trusted by an authority. iOS comes with different trusted authorites.
If the server certificate is not validated by an authority the connection is rejected.
You don't need to do something special in code. Only use a https connection.