ios - Authorizing a certificate for MCSession -

i have created self signed certificate in keychain , using multipeerconnectivity framework transfer data between devices.

when create session can pass securityidentity when invite peers in mcsession.

  - (instancetype)initwithpeer:(mcpeerid *)mypeerid securityidentity:(nsarray *)identity encryptionpreference:(mcencryptionpreference)encryptionpreference; 

but securityidentity nsarray, how can pass certificate in nsarray , how can authenticate in

- (void)session:(mcsession *)session didreceivecertificate:(nsarray *)certificate frompeer:(mcpeerid *)peerid certificatehandler:(void(^)(bool accept))certificatehandler; 

it array containing information can used identify local peer other nearby peers.

the array contains objects helps identify peer others. first secidentityref object has seckeyref object , related seccertificateref object. (it apple developer certificate , private key pair)

the other elements in array can seccertificateref objects representing intermediate certificates may needed verifying secidentityref .

the receiving peer has validate identity represented secidentityref.

below code obtain secidentityref p12 file

- (secidentityref)getclientcertificate  {     secidentityref identity = nil;     nsarray *paths = nssearchpathfordirectoriesindomains(nsdocumentdirectory, nsuserdomainmask, yes);     nsstring *documentsdirectorypath = [paths objectatindex:0];     nsstring *myfilepath = [documentsdirectorypath stringbyappendingpathcomponent:@"cert_key_pair.p12"];      nsdata *pkcs12data = [nsdata datawithcontentsoffile:myfilepath];      cfdataref inpkcs12data = (__bridge cfdataref)pkcs12data;     cfstringref password = cfstr("password");     const void *keys[] = { ksecimportexportpassphrase };//ksecimportexportpassphrase };     const void *values[] = { password };     cfdictionaryref options = cfdictionarycreate(null, keys, values, 1, null, null);     cfarrayref items = cfarraycreate(null, 0, 0, null);     osstatus securityerror = secpkcs12import(inpkcs12data, options, &items);     cfrelease(options);     cfrelease(password);     if (securityerror == errsecsuccess) {         nslog(@"success opening p12 certificate. items: %ld", cfarraygetcount(items));         cfdictionaryref identitydict = cfarraygetvalueatindex(items, 0);         identity = (secidentityref)cfdictionarygetvalue(identitydict, ksecimportitemidentity);     } else {         nslog(@"error opening certificate.");     }      return identity; } 

obtaining policy reference object , evaluating trust

- (void)session:(mcsession *)session didreceivecertificate:(nsarray *)certificate frompeer:     (mcpeerid *)peerid certificatehandler:(void (^)(bool accept))certificatehandler {      seccertificateref mycert;     mycert = [certificate objectatindex:0];    // 1      secpolicyref mypolicy = secpolicycreatebasicx509();         // 2      seccertificateref certarray[1] = { mycert };     cfarrayref mycerts = cfarraycreate(                                    null, (void *)certarray,                                    1, null);     sectrustref mytrust;     osstatus status = sectrustcreatewithcertificates(                                                 mycerts,                                                 mypolicy,                                                 &mytrust);  // 3      sectrustresulttype trustresult;     if (status == noerr) {         status = sectrustevaluate(mytrust, &trustresult);       // 4     }     //...                                                                  if (trustresult == ksectrustresultconfirm || trustresult == ksectrustresultproceed || trustresult == ksectrustresultunspecified)                           // 5     {         certificatehandler(yes);     }      // ...     if (mypolicy)     cfrelease(mypolicy);   }