CredStore Perform Query error

Question

I am running into an issue while doing API calls to my apps backend, every connection now prompts with

CredStore - performQuery - Error copying matching cred         


        

Answer 1

OK, I had this error, and fought with it for a long time (years) when interacting with my Ruby on Rails app.

I had default credentials set up as described in the accepted answer, but still got the error, and have been relying on a didReceiveChallenge response to supply the credentials - fortunately that worked as a work around.

But! I've just found the solution!

I was working on a hunch that that the protectedSpace fields did not match the Authorization challenge from the Ruby on Rails server - and I looked into the realm field, which seemed to be the only one that was being left undefined.

I started by printing out the server response headers, and although I was able to examine these, they did not include the WWW-Authorization field that would have included the realm field.

I thought this was maybe because my Rails app wasn't specifying the realm, so I started looking at the Rails side of things.

I found I could specify the realm in the call to,

authenticate_or_request_with_http_basic

...which I am using for HTTP Basic authentication.

I wasn't specifying a realm already, so added one,

authenticate_or_request_with_http_basic("My Rails App")

I then added the corresponding string to the protectionSpace,

NSURLProtectionSpace *protectionSpace =
    [[NSURLProtectionSpace alloc] initWithHost:@"myrailsapp.com"
        port:443
        protocol:NSURLProtectionSpaceHTTPS
        realm:@"My Rails App"
        authenticationMethod:NSURLAuthenticationMethodHTTPBasic];

Voila! That worked, and I no longer get the,

CredStore - performQuery - Error copying matching creds.  Error=-25300

Even after specifying the realm in the Rails app, I still don't see it passed in the HTTP header, I don't know why, but at least it works.