Request to web service over SSL - ios

Question

i am struggling to request web service using https. I am getting this kind of error:
An error occured : The certificate for this server is invalid. You might be connecting to a server that is pretending to be “SERVER_ADDRESS” which could put your confidential information at risk.
I am not using NSUrlConnectionDelegate. Here is my method:
- (void)sendRequestWithUrl:(NSURL*)url block:(void (^)(NSDictionary *dict, NSError *error)) block{
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
[request setHTTPMethod:#"POST"];
[[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate distantFuture]];
NSError* err = nil;
NSHTTPURLResponse* rsp = nil;
// Perform the request synchronously on this thread
NSData *rspData = [NSURLConnection sendSynchronousRequest:request returningResponse:&rsp error:&err];
if (rspData && err == nil) {
NSDictionary *result = [NSJSONSerialization JSONObjectWithData:rspData options:NSJSONReadingMutableLeaves error:&err];
if(result) {
block(result, err);
} else {
block(nil, err);
}
}else{
DLog(#"Requesting URL: %# An error occured : %#",url,[err localizedDescription]);
block(nil, err);
}
}
How i could solve this problem ?

Answer 1

Apple has a technote that covers this very well:
"Technical Note TN2232: HTTPS Server Trust Evaluation"
https://developer.apple.com/library/ios/#technotes/tn2232/_index.html

Answer 2

Well my solution was to create class AsyncURLConnection this code i found somewhere at http://stackoverflow.com but can't find it now. So i will give the code:
AsyncURLConnection:
.h
#import <Foundation/Foundation.h>
typedef void (^completeBlock_t)(NSData *data);
typedef void (^errorBlock_t)(NSError *error);
#interface AsyncURLConnection : NSObject{
NSMutableData *data_;
completeBlock_t completeBlock_;
errorBlock_t errorBlock_;
}
+ (id)request:(NSString *)requestUrl completeBlock:(completeBlock_t)completeBlock errorBlock:(errorBlock_t)errorBlock;
- (id)initWithRequest:(NSString *)requestUrl completeBlock:(completeBlock_t)completeBlock errorBlock:(errorBlock_t)errorBlock;
+ (id)requestWithMutable:(NSMutableURLRequest *)request completeBlock:(completeBlock_t)completeBlock errorBlock:(errorBlock_t)errorBlock;
- (id)initWithMutableRequest:(NSMutableURLRequest *)request completeBlock:(completeBlock_t)completeBlock errorBlock:(errorBlock_t)errorBlock;
#end
.m
#import "AsyncURLConnection.h"
#implementation AsyncURLConnection
+ (id)requestWithMutable:(NSMutableURLRequest *)request completeBlock:(completeBlock_t)completeBlock errorBlock:(errorBlock_t)errorBlock
{
return [[self alloc] initWithMutableRequest:request completeBlock:completeBlock errorBlock:errorBlock];
}
+ (id)request:(NSString*)requestUrl completeBlock:(completeBlock_t)completeBlock errorBlock:(errorBlock_t)errorBlock
{
return [[self alloc] initWithRequest:requestUrl
completeBlock:completeBlock errorBlock:errorBlock];
}
- (id)initWithRequest:(NSString *)requestUrl completeBlock:(completeBlock_t)completeBlock errorBlock:(errorBlock_t)errorBlock
{
if ((self=[super init])) {
data_ = [[NSMutableData alloc] init];
completeBlock_ = [completeBlock copy];
errorBlock_ = [errorBlock copy];
NSURL *url = [NSURL URLWithString:requestUrl];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
[NSURLConnection connectionWithRequest:request delegate:self];
}
return self;
}
- (id)initWithMutableRequest:(NSMutableURLRequest *)request completeBlock:(completeBlock_t)completeBlock errorBlock:(errorBlock_t)errorBlock
{
if ((self=[super init])) {
data_ = [[NSMutableData alloc] init];
completeBlock_ = [completeBlock copy];
errorBlock_ = [errorBlock copy];
[NSURLConnection connectionWithRequest:request delegate:self];
}
return self;
}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
[data_ setLength:0];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
[data_ appendData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
completeBlock_(data_);
}
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
errorBlock_(error);
}
- (void)connection:(NSURLConnection *)connection willSendRequestForAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge {
if ([challenge previousFailureCount] == 0)
{
NSURLCredential *newCredential;
newCredential=[NSURLCredential credentialWithUser:#"someUser"
password:#"someUser"
persistence:NSURLCredentialPersistenceForSession];
[[challenge sender] useCredential:newCredential forAuthenticationChallenge:challenge];
DLog(#"responded to authentication challenge");
}else{
DLog(#"previous authentication failure");
}
}
So in some controller this class could be used:
+ (void) downloadFileForURL:(NSURL *) url completionBlock:(void (^)(NSData *data, NSError *error)) block {
NSString *requestURL = #"https://www.google.lt/restServer/Method";
[AsyncURLConnection request:requestURL completeBlock:^(NSData *data) {
/* success! */
dispatch_queue_t downloadQueue = dispatch_queue_create("Download queue", NULL);
dispatch_async(downloadQueue, ^{
/* process downloaded data in Concurrent Queue */
if (data != nil) {
block(data, nil);
}else{
block(nil,nil);
}
dispatch_async(dispatch_get_main_queue(), ^{
/* update UI on Main Thread */
});
});
} errorBlock:^(NSError *error) {
/* error! */
block(nil,error);
}];
}
Hope some one this code could help.
Thank you all for answers.

Answer 3

You should add below delegate methods to your communication class.
- (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge
{
if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])
{
if ([YOUR_HOST isEqualToString:challenge.protectionSpace.host])
{
[challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];
}
}
[challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];
}
- (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace
{
return [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust];
}

Answer 4

This always happen for self-signed certificate. By using NSURLConnectionDelegate
- (BOOL)connection:(NSURLConnection *)connection
canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace
{
if ([protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust]) {
return YES;
}
}

Answer 5

Trying this delegate method solved same issue for me.
- (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace {
return [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust];
}
- (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge {
[challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];
[challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];
}