如何使用NSURLConnection发布SAML响应消息？

我正在创建一个允许用户与安全服务器进行交互的iPhone应用程序。但是，要验证用户，应用程序需要通过SAML从用户登录到服务器的数据所在的服务器（提供SSO）。因此，该应用程序模仿发送SAML HTTP请求（通常浏览器会照顾）。如何使用NSURLConnection发布SAML响应消息？

该过程使用Mechanize gem与Ruby一起工作，但现在我无法使用NSURLConnection在iPhone上工作。

我碰到的问题是：似乎base64编码的SAML响应没有通过NSURLConnection正确发送到服务器。 +号被空格替换，导致服务器端的SAML响应解码失败。对stringByAddingPercentEscapesUsingEncoding使用URL编码会导致相同的解码错误。

这是代码提取和发送SAML响应：

// Extract the SAML Response from the form that is sent by the server 
body = [[NSString alloc] initWithData:[self receivedData]  encoding:NSUTF8StringEncoding]; 
NSString *searchSAMLResponseStart = @"name=\"SAMLResponse\" value=\""; 
NSString *searchSAMLResponseEnd = @">\n<NOSCRIPT><INPUT TYPE=\"SUBMIT\""; 
NSRange samlResponseStartRange = [body rangeOfString:searchSAMLResponseStart options:0]; 
NSRange samlResponseEndRange = [body rangeOfString:searchSAMLResponseEnd options:0]; 
NSRange range = NSMakeRange (NSMaxRange(samlResponseStartRange), samlResponseEndRange.location - NSMaxRange(samlResponseStartRange) -1); 
NSString* samlResponseString = [body substringWithRange:range]; 

// Construct the SAML POST request 
NSURL    *url; 
NSMutableURLRequest *request; 
url = [NSURL URLWithString:kSamlPostUrl]; 
request = [NSMutableURLRequest requestWithURL:url]; 
NSString *userAgent = kUserAgent; 
[request setValue:userAgent forHTTPHeaderField:@"User-Agent"]; 
[request setHTTPMethod:@"POST"]; 
NSString *post = [@"RelayState=https://example.com&SAMLResponse=" stringByAppendingString:samlResponseString]; 
NSData *postData = [post dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:NO]; 
NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]]; 
[request setValue:postLength forHTTPHeaderField:@"Content-Length"]; 
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"]; 
[request setHTTPBody:postData]; 

// Send the request   
self.connectionPostSaml = [NSURLConnection connectionWithRequest:request delegate:self];

的SAML表单服务器发送并在SAML响应摘自，看起来是这样的：

<html> 
<HEAD><META HTTP-EQUIV='PRAGMA' CONTENT='NO-CACHE'><META HTTP-EQUIV='CACHE-CONTROL'  CONTENT='NO-CACHE'><TITLE>SAML 2.0 Auto-POST form</TITLE></HEAD> 
    <body onLoad="document.forms[0].submit()"> 
<NOSCRIPT>Your browser does not support JavaScript. Please click the 'Continue' button  below to proceed. <br><br></NOSCRIPT> 
     <form action="https://sso.example.com/saml2" method="POST"> 
     <input type="hidden" name="RelayState" value="https://example.com"> 
     <input type="hidden" name="SAMLResponse"  value="PFJlc3BvbnNlIHhtbG5zPSJ1cm46b2FzaXM6bmFtZXM6dGM6U0FNTDoyLjA6cHJvdG9jb2wiIERl 
c3RpbmF0aW9uPSJodHRwczovL3Nzby5vcG93ZXIuY29tL3NwL0FDUy5zYW1sMiIgSUQ9Il85ZWY0 
M2MzMGRkZmQ0YzY1ODNiMjgxZjAwNDU5ZWQyMjZmMjQiIElzc3VlSW5zdGFudD0iMjAxMi0wMy0y 
OFQyMTo0MDowNloiIFZlcnNpb249IjIuMCI+CiAgICA8bnMxOklzc3VlciB4bWxuczpuczE9InVy 
bjpvYXNpczpuYW1lczp0YzpTQU1MOjIuMDphc3NlcnRpb24iIEZvcm1hdD0idXJuOm9hc2lzOm5h 
bWVzOnRjOlNBTUw6Mi4wOm5hbWVpZC1mb3JtYXQ6ZW50aXR5Ij5wZ2UuY29tPC9uczE6SXNzdWVy 
(…) 
cnRpb24+CjwvUmVzcG9uc2U+"> 
<NOSCRIPT><INPUT TYPE="SUBMIT" VALUE="Continue"></NOSCRIPT> 
     </form> 
    </body> 
</html>

而且服务器收到POST请求后产生的错误：

Unable to parse incoming SAML2 message, raw:  PFJlc3BvbnNlIHhtbG5zPSJ1cm46b2FzaXM6bmFtZXM6dGM6U0FNTDoyLjA6cHJvdG9jb2wiIERl 
c3RpbmF0aW9uPSJodHRwczovL3Nzby5vcG93ZXIuY29tL3NwL0FDUy5zYW1sMiIgSUQ9Il9iN2Q5 
OTZhMmI1MjhiNWRkNjY0YWM4YjUwZmVjM2M2OTMzMWEiIElzc3VlSW5zdGFudD0iMjAxMi0wMy0y 
OVQyMjowMzoxNVoiIFZlcnNpb249IjIuMCI CiAgICA8bnMxOklzc3VlciB4bWxuczpuczE9InVy 
bjpvYXNpczpuYW1lczp0YzpTQU1MOjIuMDphc3NlcnRpb24iIEZvcm1hdD0idXJuOm9hc2lzOm5h 
bWVzOnRjOlNBTUw6Mi4wOm5hbWVpZC1mb3JtYXQ6ZW50aXR5Ij5wZ2UuY29tPC9uczE6SXNzdWVy 
PgogICAgPFN0YXR1cz4KICAgICAgICA8U3RhdHVzQ29kZSBWYWx1ZT0idXJuOm9hc2lzOm5hbWVz 
OnRjOlNBTUw6Mi4wOnN0YXR1czpTdWNjZXNzIi8 CiAgICA8L1N0YXR1cz4KICAgIDxuczI6QXNz 
(…)

请注意t他在原始回应中的标志被改为空格。

这似乎是服务器解码接收到的响应，因此用空格替换+符号的正常行为：但是，为什么当SAML表单从浏览器发布，而不是从NSURLConnection发布时，它工作？使用不同的编码来解码和编码SAML响应

：

为了解决我尝试。现在，使用NSUTF8StringEncoding，也尝试：NSASCIIStringEncoding，NSNEXTSTEPStringEncoding，NSNonLossyASCIIStringEncoding，NSUnicodeStringEncoding
使用stringByAddingPercentEscapesUsingEncoding，所以这行代码：

的NSString * samlResponseString = [身体substringWithRange：范围];

变为：

NSString* samlResponseString = [[body substringWithRange:range] stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

使用其他enctypes的形式，但服务器甚至不会接受这些要求：的multipart/form-data的 text/plain的

我非常感谢你的帮助。先谢谢你！

来源

2012-03-29 user1246146

我有一个问题，通过发送base64并通过url编码解决它。试试这个：

NSString *post = [@"RelayState=https://example.com&SAMLResponse=" stringByAppendingString: 
     (__bridge_transfer NSString *)CFURLCreateStringByAddingPercentEscapes(NULL, 
     (__bridge CFStringRef)samlResponseString, NULL, (CFStringRef)@"!*'\"();:@&=+$,/?%#[]% ", 
     CFStringConvertNSStringEncodingToEncoding(NSUTF8StringEncoding))];

来源

2013-04-11 15:24:58 Bushrod

如何使用NSURLConnection发布SAML响应消息？

回答

相关问题