Integração do aplicativo para iPhone com Shibboleth

Question

Alguém integrou um aplicativo para iPhone com um provedor de identidade Shibboleth? O Google não criou nada, então estou perguntando diretamente aos gurus.

Se não foi dones anteriormente, é viável fazê -lo?

Answer 1

A resposta para ambos é "sim".

Eu sou um cara de Java, então me pediram há duas semanas para:

• Aprenda Objetivo-C
• Escreva um aplicativo nativo para iPhone
• Autenticado programaticamente com shibboleth
• Faça o download de uma exibição Shibboleth Protected Datafile

... foi um pouco assustador. Componha isso com a ausência de qualquer postagem do fórum para ajudar me levou a compartilhar minha experiência.

Aqui está uma visão geral seguida por alguns códigos de amostra muito úteis. Por favor, vote na minha resposta se isso ajudar! Vale algumas semanas do meu tempo :)

Para um aplicativo no iPhone baixar recursos shibbolizados, o seguinte precisa acontecer:

1. Use as APIs de URL no cacau para enviar a solicitação HTTP para o recurso em questão.
2. Implementar uma classe delegada para a solicitação para:
3. Responda ao SP re-diretamente ao IDP (cortesia automática do cacau)
4. Responda aos desafios de confiança do certificado do servidor
5. Responda aos desafios de credenciais do usuário
6. Responda a erros (se necessário)
7. Receba o "modelo de ligação" do IDP para o usuário autenticado, um formulário HTML que re-direciona o usuário de volta ao SP com dois parâmetros
8. Programaticamente HTTP Publique os dois parâmetros do IDP de volta ao SP.
9. Os cookies são automaticamente armazenados e a avanços cortesia de cacau novamente
10. Implementar um segundo delegado de solicitação de URL para receber os dados de solicitar originalmente.

Aqui estão algumas referências úteis da Apple e Shibboleth:

• http://developer.apple.com/mac/library/documentation/cocoa/conceptual/urlloadingsystem/urlloadingsystem.html
• https://spaces.internet2.edu/display/shib2/idpsplocaltInstall

E espero poder incluir toda a fonte para uma demonstração rápida.

ApplicationDelegate.h
----------
#import <UIKit/UIKit.h>
#import "ConsoleViewController.h"

/*
 The application delegate will hold references to the application's UIWindow and a ConsoleViewController.
 The console does all of the interesting Shibboleth activities.
*/
@interface ApplicationDelegate : NSObject <UIApplicationDelegate> {

 UIWindow *window;
 ConsoleViewController *consoleViewController;
}


@end

ApplicationDelegate.m
----------
#import "ApplicationDelegate.h"
#import "ConsoleViewController.h"

/*
 The implementation for the ApplicationDelegate initializes the console view controller and assembles everything.
 The console does all of the interesting Shibboleth activities.
 */
@implementation ApplicationDelegate


- (void)applicationDidFinishLaunching:(UIApplication *)application {    

 // Initialize the console.
 consoleViewController = [[ConsoleViewController alloc] init];

 window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
 [window setBackgroundColor:[UIColor lightGrayColor]];
 [window addSubview:[consoleViewController view]];

 [window makeKeyAndVisible];
}


- (void)dealloc {
    [window release];
 [ConsoleViewController release];
    [super dealloc];
}


@end

ConsoleController.h
----------
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>

/*
 The ConsoleViewController's interface declares references to the network data used in negotiating with Shibboleth
 and a UITextView used to display the final result or errors.
 */
@interface ConsoleViewController : UIViewController {

 NSMutableData *responseData;
 NSString *responseString;
 UITextView *console;
}

@end

ConsoleController.m
----------
#import "ApplicationDelegate.h"
#import "ConsoleViewController.h"


/*
 This delegate is used when making the second HTTP request with Shibboleth.  If you're just getting here, start
 by reading the comments for ConsoleViewController below.

 All we need to do now is receive the response from the SP and display it.
 If all goes well, this should be the secured page originally requested.
 */
@interface AuthenticationRedirectDelegate : NSObject {

 NSMutableData *authResponseData;
 NSString *authResponseString;
 UITextView *console;
}

@property (nonatomic retain) UITextView *console;

@end


/*
 Refer to the comments for the interface above.
 */
@implementation AuthenticationRedirectDelegate

@synthesize console;

-(id)init {
 authResponseData = [[NSMutableData alloc] retain];
 return self;
}


- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
 [authResponseData setLength:0];
}


- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
 [authResponseData appendData:data];
}


- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
 [console setText:[error localizedDescription]]; 
}


/*
 Once the data is received from Shibboleth's SP, display it.
 */
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {  

 authResponseString = [[NSString alloc] initWithData:authResponseData encoding:NSUTF8StringEncoding]; 
 [console setText:authResponseString]; 
 [connection release];
}


@end


/*
 The implementation of the ConsoleViewController, and AuthenticationRedirectDelegate above, contain the real logic of
 this Shibboleth exercise.  The ConsoleViewController performs the following:
 1. Prepare the initial HTTP request to a Shibboleth protected resource.
 2. Act as the delegate whilst Cocoa's URL Loading API receives the HTTP Response.
 NOTE: We instruct Cocoa in advance to take care of the SP redirecting to the IdP, accepting the server certificate,
 and submitting the user credentials
 3. Once the HTTP Response is finished loading, parse the <form action, RelayState and SAMLResponse from the IdP's
 response
 4. Call a utility method to prepare a second HTTP POST Request to the <form action/SP with the IdP's parameters
 NOTE: We do not need to transfer over any of Shibboleth's cookies, since Cocoa is doing this automatically
 5. Use a new instance of AuthenticationRedirectDelegate to receive the POST's response, which should be the secured
 page originally requested.
 6. Display the final content in the UITextView known as console.
 */
@implementation ConsoleViewController


/*
 A handy utility method for extracting a substring marked by two provided token strings.
 Used in parsing the HTML form returned by the IdP after the first HTTP Request.
 */
+(id)substringFromString:(NSString *)source BetweenOpenToken:(NSString *)openToken AndCloseToken:(NSString *)closeToken {

 NSUInteger l = [source length];
 NSUInteger openTokenLen = [openToken length];

 NSUInteger openTokenLoc = ([source rangeOfString:openToken]).location;
 NSUInteger valueLoc = openTokenLoc + openTokenLen;
 NSRange searchRange = NSMakeRange(valueLoc, l - valueLoc);
 NSUInteger closeTokenLoc = ([source rangeOfString:closeToken options:NSCaseInsensitiveSearch range:searchRange]).location;
 searchRange = NSMakeRange(valueLoc, closeTokenLoc - valueLoc);
 NSString *result = [source substringWithRange:searchRange];

 return result;
}


/*
 This function takes the three properties returned by the IdP after the first HTTP request and 
 HTTP POSTs them to the SP as specified by the IdP in the "url" parameter.
 */
-(void)authReturnTo:(NSURL *)url WithRelay:(NSString *)relayState AndSAML:(NSString *)samlResponse {

 // Here we assemble the HTTP POST body as usual.
 NSString *preBody = [[NSString alloc] initWithString:@"RelayState="];
 preBody = [preBody stringByAppendingString:relayState];
 preBody = [preBody stringByAppendingString:@"&"];
 preBody = [preBody stringByAppendingString:@"SAMLResponse="];
 preBody = [preBody stringByAppendingString:samlResponse];

 /* The SAMLResponse parameter contains characters (+) that the SP expects to be URL encoded.
  Here we simply manually URL encode those characters.  You may wish to harden this with proper
  URL encoding for production use.
  */
 NSString *httpBody = [preBody stringByReplacingOccurrencesOfString:@"+" withString:@"%2B"];
 NSData *httpBodyData = [httpBody dataUsingEncoding:NSUTF8StringEncoding];

 NSString *httpContentLength = [NSString stringWithFormat:@"%d", [httpBodyData length]];

 NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url
              cachePolicy:NSURLRequestReloadIgnoringCacheData
              timeoutInterval:12.0];
 [request setHTTPMethod:@"POST"];
 [request setValue:httpContentLength forHTTPHeaderField:@"Content-Length"];
 [request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];

 [request setHTTPBody:httpBodyData];

 // Submit the HTTP POST using the second delegate class to receive the response
 AuthenticationRedirectDelegate *delegate = [[AuthenticationRedirectDelegate alloc] init];
 delegate.console=console;
 [[NSURLConnection alloc] initWithRequest:request delegate:delegate];
}


/*
 When this UIViewController finishes loading, automatically prepare and send a request to the Shibboleth SP Web Server
 for a secured resource.
 */
- (void)viewDidLoad {
 [super viewDidLoad];

 console = [[UITextView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
 [[self view] addSubview:console];

 responseData = [[NSMutableData data] retain];

 // TODO: Enter your own URL for a Shibboleth secured resource.
 NSURL *url = [NSURL URLWithString:@"<URL>"];

 NSURLRequest *request = [NSURLRequest requestWithURL:url
       cachePolicy:NSURLRequestUseProtocolCachePolicy
       timeoutInterval:12.0];

 [[NSURLConnection alloc] initWithRequest:request delegate:self];

 /* Control flows to the delegate methods below */
}


/*
 Refer to Apple's docs on the URL Loading System for details.
 http://developer.apple.com/mac/library/DOCUMENTATION/Cocoa/Conceptual/URLLoadingSystem/URLLoadingSystem.html
 */
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
  [responseData setLength:0];
}


/*
 Refer to Apple's docs on the URL Loading System for details.
 http://developer.apple.com/mac/library/DOCUMENTATION/Cocoa/Conceptual/URLLoadingSystem/URLLoadingSystem.html
 */
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
 [responseData appendData:data];
}

/*
 This implementation in the delegate let's Cocoa trust my SP Web Server's self-signed certificate.
 TODO: You will want to harden this for production use.

 Refer to Apple's docs on the URL Loading System for details.
 http://developer.apple.com/mac/library/DOCUMENTATION/Cocoa/Conceptual/URLLoadingSystem/URLLoadingSystem.html
 */
- (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace {
 return [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust] || [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodHTTPBasic];
}


/*
 This implementation for the delegate does two things:
 1. Respond to challenges for my server's self-signed certificate
 2. Respond to the IdP's challenge for the username and password.
 TODO: Enter your own username and password here.
 Refer to Apple's docs on the URL Loading System for details.
 http://developer.apple.com/mac/library/DOCUMENTATION/Cocoa/Conceptual/URLLoadingSystem/URLLoadingSystem.html
 */
- (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge {
 // TODO: Enter the correct username and password below.
 /*
  WARNING: Using an incorrect user name and password will result in your application being re-challenged
  by the IdP.  Cocoa will return to this function in a never-ending loop.  This can result in the message
  "NSPosixErrorDomain Too many open files".  You'll need to perform additional coding to handle this.
  */
 if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])
  [challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];
 else if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodHTTPBasic])
  [challenge.sender useCredential:[NSURLCredential credentialWithUser:@"<USERNAME>" password:@"<PASSWORD>" persistence:NSURLCredentialPersistenceNone] forAuthenticationChallenge:challenge];
 else
  [challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];
}


/*
 You may wish to add more code here to log errors.

 Refer to Apple's docs on the URL Loading System for details.
 http://developer.apple.com/mac/library/DOCUMENTATION/Cocoa/Conceptual/URLLoadingSystem/URLLoadingSystem.html
 */
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
 [console setText:[error localizedDescription]];
}


/*
 Once Cocoa has received a (hopefully) authenticated response from the IdP, we parse out the relevant pieces and prepare to
 HTTP POST them back to the SP as specified by the IdP in the <form action attribute.

 Refer to Apple's docs on the URL Loading System for details.
 http://developer.apple.com/mac/library/DOCUMENTATION/Cocoa/Conceptual/URLLoadingSystem/URLLoadingSystem.html
 */
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {  
 [connection release];
 responseString = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];

 if([responseString rangeOfString:@"SAMLResponse"].length < 1)
 {
  [console setText:[@"Unexpected response:\n]n" stringByAppendingString:responseString]];
  return;
 }

 NSString *relayState = [ConsoleViewController substringFromString:responseString BetweenOpenToken:@"RelayState\" value=\"" AndCloseToken:@"\"/>"];
 NSString *SAMLResponse = [ConsoleViewController substringFromString:responseString BetweenOpenToken:@"SAMLResponse\" value=\"" AndCloseToken:@"\"/>"];
 NSString *formAction = [ConsoleViewController substringFromString:responseString BetweenOpenToken:@"<form action=\"" AndCloseToken:@"\""];
 NSURL *formActionURL = [[NSURL alloc] initWithString:formAction];
 [self authReturnTo:formActionURL WithRelay:relayState AndSAML:SAMLResponse];
}


@end

Answer 2

Consegui fazer exatamente isso, mas levei algum tempo para entender cada passo do processo e reproduzi -lo perfeitamente. Se eu tiver tempo, posso escrever um tutorial detalhado, porque não encontrei ajuda para muitos problemas que tive. O problema é que também depende do site para o qual você deseja se conectar, para que o seu talvez não siga o mesmo caminho que o meu (seu processo é o mesmo que o descrito descrito aqui).

Para ver todas as solicitações demitidas pelo meu navegador (Chrome) para conectar, usei o painel de rede de ferramentas do desenvolvedor, com o 'Log Reserve' verificado.

Algumas dicas:

• 1 °) você precisa obter "_idp_authn_lc_key ..." Cookie. Há um pedido que o defina, encontre -o.

• 2 °) você precisa do tíquete de login (LT -...). Você provavelmente o encontrará no corpo da página que solicita suas credenciais.

• 3 °) você precisa de um ticket de serviço (ST -...). Novamente, você encontrará na página que a solicitação anterior retornou.

• 4 °) você precisa de SamlResponse. Novamente, você encontrará na página que a solicitação anterior retornou.

• 5 °) Finalmente, você pode efetuar login enviando de volta o SAMLRESPONHO para o provedor de serviços. Você deve cuidar da codificação, aqui. Eu tinha alguns '+' ou '=' que eu precisava mudar para '%2b' e '%3D'. Você receberá um cookie "_idp_session", que permitirá que você se reconecte sem toda essa bagunça.

Se alguém tentar fazer o mesmo, ficaria feliz em ajudar! Apenas me envie uma mensagem.

Answer 3

Eu implementei com sucesso usando a solução da CE como ponto de partida. A única outra coisa que acrescentaria é que você realmente precisa prestar atenção em manter apenas uma solicitação de cada vez. Em nossa implementação, o processo de autenticação ficaria confuso entre várias solicitações assíncronas em execução simultaneamente. Usando a NSOPERATION para acelerar a fila parecia funcionar muito bem para mim.