如何以编程方式将证书导入我的iOS应用程序的钥匙串，并在需要时将身份传递给服务器？

Question

我正在开发一个iOS5应用程序，它将促进两个用户之间的移动支付。作为付款流程的一部分，发件人和收件人需要与服务器通信。服务器要求双方在连接时启动身份验证质询时显示其身份。

目前，我在代码中使用以下两种方法对证书过程进行了硬编码：

NSURLConnection委托didReceiveAuthenticationChallenge

(void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:    (NSURLAuthenticationChallenge *)challenge
{
NSLog(@"Authentication challenge");

// Load Certificate
NSString *path = [[NSBundle mainBundle] pathForResource:@"PKCS12" ofType:@"p12"];
NSData *p12data = [NSData dataWithContentsOfFile:path];
CFDataRef inP12data = (__bridge CFDataRef)p12data;

SecIdentityRef myIdentity;
SecTrustRef myTrust;
extractIdentityAndTrust(inP12data, &myIdentity, &myTrust);

SecCertificateRef myCertificate;
SecIdentityCopyCertificate(myIdentity, &myCertificate);
const void *certs[] = { myCertificate };
CFArrayRef certsArray = CFArrayCreate(NULL, certs, 1, NULL);

NSURLCredential *credential = [NSURLCredential credentialWithIdentity:myIdentity certificates:(__bridge NSArray*)certsArray persistence:NSURLCredentialPersistencePermanent];

[[challenge sender] useCredential:credential forAuthenticationChallenge:challenge];
}

C方法extractIdentityAndTrust

OSStatus extractIdentityAndTrust(CFDataRef inP12data, SecIdentityRef *identity, SecTrustRef *trust)
{
OSStatus securityError = errSecSuccess;

CFStringRef password = CFSTR("password");
const void *keys[] = { kSecImportExportPassphrase };
const void *values[] = { password };

CFDictionaryRef options = CFDictionaryCreate(NULL, keys, values, 1, NULL, NULL);

CFArrayRef items = CFArrayCreate(NULL, 0, 0, NULL);
securityError = SecPKCS12Import(inP12data, options, &items);

if (securityError == 0) {
    CFDictionaryRef myIdentityAndTrust = CFArrayGetValueAtIndex(items, 0);
    const void *tempIdentity = NULL;
    tempIdentity = CFDictionaryGetValue(myIdentityAndTrust, kSecImportItemIdentity);
    *identity = (SecIdentityRef)tempIdentity;
    const void *tempTrust = NULL;
    tempTrust = CFDictionaryGetValue(myIdentityAndTrust, kSecImportItemTrust);
    *trust = (SecTrustRef)tempTrust;
}

if (options) {
    CFRelease(options);
}

return securityError;
}

我已多次测试此代码并取得了成功。现在我试图继续并允许存储适当的身份，然后从应用程序的钥匙串中检索。我的目标是允许用户通过iTunes文件共享或Dropbox导入他们的P12文件并将其保存到钥匙串。

我查看了Apple的Getting and Using Persistent Keychain References文档，并且无法弄清楚如何导入身份。他们的代码对我来说有点混乱，因为他们使用未声明的变量/引用（特别是

&persistent_ref

变量）。如果有人可以帮助破译它，那将非常感激。

TL; DR：如何将P12文件的内容保存到我的iOS 5应用程序钥匙串中，稍后将其检索到NSURLConnection didReceiveAuthenticationChallenge方法？

Answer 1

以下代码应该可以解决问题：

NSMutableDictionary *secIdentityParams = [[NSMutableDictionary alloc] init];
[secIdentityParams setObject:(id)myIdentity forKey:(id)kSecValueRef];
OSStatus status = SecItemAdd((CFDictionaryRef) secIdentityParams, NULL);

您可以通过传递要查找或创建的键值对字典来与Keychain进行交互。每个键代表一个搜索选项或钥匙串中项目的属性。键是预定义的常量，必须根据要存储的数据类型使用。这些密钥可以在Apple的开发人员文档中找到。

我认为Apple的源代码确实缺少persistentRef的分配。他们应该在方法的开头添加这样的声明：

NSData *persistentRef = nil; 

请注意，使用持久性引用不是强制性的。上面的代码应该可以正常工作。正如Apple解释得好：

因为持久引用在程序调用之间保持有效并且可以存储在磁盘上，所以您可以使用一个来更容易地找到您需要重复使用的Keychain项目

来源：https://developer.apple.com/library/ios/#documentation/Security/Conceptual/CertKeyTrustProgGuide/iPhone_Tasks/iPhone_Tasks.html#//apple_ref/doc/uid/TP40001358-CH208-DontLinkElementID_10

Answer 2

Swift 4.0

 if let url = Bundle.main.url(forResource: "XXX", withExtension: "pem") {

            let PKCS12Data = NSData(contentsOf: url)
            let inPKCS12Data = CFDataCreate(kCFAllocatorDefault, PKCS12Data!.bytes.assumingMemoryBound(to: UInt8.self), (PKCS12Data?.length)!)

            let keys: [CFString] = [kSecImportExportPassphrase]
            let values: [CFTypeRef] = []

            let keysPointer = UnsafeMutablePointer<UnsafeRawPointer?>.allocate(capacity: keys.count)
            keysPointer.initialize(to: keys)

            let valuesPointer = UnsafeMutablePointer<UnsafeRawPointer?>.allocate(capacity: values.count)
            valuesPointer.initialize(to: values)

            let optionsDictionary = CFDictionaryCreate(kCFAllocatorDefault, keysPointer, valuesPointer, 1, nil, nil)

            var items = CFArrayCreate(kCFAllocatorDefault, UnsafeMutablePointer<UnsafeRawPointer?>.allocate(capacity: 0), 0, nil)
            let securityError = SecPKCS12Import(inPKCS12Data!, optionsDictionary!, &items)
            if (securityError == 0) {
                print("Certificate installed Successfully")
            } else {
                print("Certificate installation failed")
            }

    }