To override the hostname (to allow a certificate for one specific site
to work for another specific site,or to allow a certificate to work
when you connected to a host by its IP address),you must replace
the policy object that the trust policy uses to determine how to
interpret the certificate. To do this,first create a new TLS policy
object for the desired hostname. Then create an array containing that
policy. Finally,tell the trust object to use that array for future
evaluation of trust.@H_502_5@

SecTrustRef changeHostForTrust(SecTrustRef trust)
{
        CFMutableArrayRef newTrustPolicies = CFArrayCreateMutable(
                kcfAllocatorDefault,&kcfTypeArrayCallBacks);

        SecPolicyRef sslPolicy = SecPolicyCreateSSL(true,CFSTR("www.example.com"));

        CFArrayAppendValue(newTrustPolicies,sslPolicy);

#ifdef MAC_BACKWARDS_COMPATIBILITY
        /* This technique works in OS X (v10.5 and later) */

        SecTrustSetPolicies(trust,newTrustPolicies);
        CFRelease(oldTrustPolicies);

        return trust;
#else
        /* This technique works in iOS 2 and later,or
           OS X v10.7 and later */

        CFMutableArrayRef certificates = CFArrayCreateMutable(
                kcfAllocatorDefault,&kcfTypeArrayCallBacks);

        /* Copy the certificates from the original trust object */
        CFIndex count = SecTrustGetCertificateCount(trust);
        CFIndex i=0;
        for (i = 0; i < count; i++) {
                SecCertificateRef item = SecTrustGetCertificateAtIndex(trust,i);
                CFArrayAppendValue(certificates,item);
        }

        /* Create a new trust object */
        SecTrustRef newtrust = NULL;
        if (SecTrustCreateWithCertificates(certificates,newTrustPolicies,&newtrust) != errSecSuccess) {
                /* Probably a good spot to log something. */

                return NULL;
        }

        return newtrust;
#endif
}

资料来源：iOS Developer Library — Overriding TLS Chain Validation Correctly — Manipulating Trust Objects@H_502_5@

请注意,在同一页面上,您可以找到处理自签名SSL证书的其他代码段,以防您处理此类证书.@H_502_5@

要在Swift项目中使用此功能,请将新的C文件添加到您的项目(File .. New .. File .. iOS / Source / C_File),例如mysectrust.c和相应的头mysectrust.h(如果XCode要求你创建一个桥接头,说是)@H_502_5@

mysectrust.h@H_502_5@

#ifndef mysectrust_h
#define mysectrust_h

#include <Security/Security.h>

SecTrustRef changeHostForTrust(SecTrustRef trust);

#endif /* mysectrust_h */

mysectrust.c@H_502_5@

#include "mysectrust.h"

SecTrustRef changeHostForTrust(SecTrustRef trust)
{
    CFMutableArrayRef newTrustPolicies = CFArrayCreateMutable(
                                                              kcfAllocatorDefault,&kcfTypeArrayCallBacks);

    SecPolicyRef sslPolicy = SecPolicyCreateSSL(true,CFSTR("www.example.com"));

    CFArrayAppendValue(newTrustPolicies,sslPolicy);

#ifdef MAC_BACKWARDS_COMPATIBILITY
    /* This technique works in OS X (v10.5 and later) */

    SecTrustSetPolicies(trust,newTrustPolicies);
    CFRelease(oldTrustPolicies);

    return trust;
#else
    /* This technique works in iOS 2 and later,or
     OS X v10.7 and later */

    CFMutableArrayRef certificates = CFArrayCreateMutable(
                                                          kcfAllocatorDefault,&kcfTypeArrayCallBacks);

    /* Copy the certificates from the original trust object */
    CFIndex count = SecTrustGetCertificateCount(trust);
    CFIndex i=0;
    for (i = 0; i < count; i++) {
        SecCertificateRef item = SecTrustGetCertificateAtIndex(trust,i);
        CFArrayAppendValue(certificates,item);
    }

    /* Create a new trust object */
    SecTrustRef newtrust = NULL;
    if (SecTrustCreateWithCertificates(certificates,&newtrust) != errSecSuccess) {
        /* Probably a good spot to log something. */

        return NULL;
    }

    return newtrust;
#endif
}

当然,请使用您的主机名替换上述代码中的www.example.com.@H_502_5@

然后,在Xcode项目projectname-Bridging-Header.h中找到桥接头,并附加以下行：@H_502_5@

#import "mysectrust.h"

现在你可以从Swift调用这个函数,例如：@H_502_5@

func whatever(trust: SecTrustRef){

    let newTrust = changeHostForTrust(trust) // call to C function
    ...
}