swift3 - CFDictionaryCreate crashes in Xcode 8 swift 3 -

i have following code retrieving , storing rsakeydata

fileprivate func retrieveandstorersakeydata(ispublic: bool) throws -> cfdata {      var resultcode = noerr     var result: cfdata     let value = {         if ispublic {             let t = self.publictag             print(t)         }         else         {             let s = self.privatetag             print(s)         }     }     var keycallbacks = kcftypedictionarykeycallbacks     var valuecallbacks = kcftypedictionaryvaluecallbacks     let keys = [unmanaged.passunretained(ksecclass).toopaque(), unmanaged.passunretained(ksecattrapplicationtag).toopaque(), unmanaged.passunretained(ksecattrkeytype).toopaque(), unmanaged.passunretained(ksecreturndata).toopaque()]     let values = [unmanaged.passunretained(ksecclasskey).toopaque(), unmanaged<anyobject>.passunretained(value anyobject).toopaque(), unmanaged.passunretained(ksecattrkeytypersa).toopaque(), unmanaged.passunretained(kcfbooleantrue).toopaque()]     let querykey = cfdictionarycreate(kcfallocatordefault,unsafemutablepointer.allocate(capacity: keys.count),unsafemutablepointer.allocate(capacity: values.count), 4, &keycallbacks, &valuecallbacks)      // key.     var item: anyobject?     resultcode = secitemcopymatching(querykey!, &item)      if(resultcode != noerr) {          try generatekeypair()         /*         recurcively call retrieval again after keys have been generated         */         result = try retrieveandstorersakeydata(ispublic: ispublic)     }     else {          result = item as! cfdata     }      return result } 

the cfdictionarycreate fails , code crashes in line in

     let querykey = cfdictionarycreate(kcfallocatordefault,unsafemutablepointer.allocate(capacity: keys.count),unsafemutablepointer.allocate(capacity: values.count), 4, &keycallbacks, &valuecallbacks) 

can me out on this. in advance

to generate key pair

func generatekeypair(_ publictag: string, privatetag: string, keysize: int)->bool {         let privateattributes = [string(ksecattrispermanent): true,                                  string(ksecattrapplicationtag): privatetag] [string : any]         let publicattributes = [string(ksecattrispermanent): true,                                 string(ksecattrapplicationtag): publictag] [string : any]          let pairattributes = [string(ksecattrkeytype): ksecattrkeytypersa,                               string(ksecattrkeysizeinbits): keysize,                               string(ksecpublickeyattrs): publicattributes,                               string(ksecprivatekeyattrs): privateattributes] [string : any]          var publicref: seckey?         var privateref: seckey?         switch seckeygeneratepair(pairattributes cfdictionary, &publicref, &privateref) {         case noerr: return true         default: return false         }     } 

and few helper functions

func obtainkey(_ tag: string) -> seckey? {     var keyref: anyobject?     let query: dictionary<string, anyobject> = [         string(ksecattrkeytype): ksecattrkeytypersa,         string(ksecreturnref): kcfbooleantrue cfboolean,         string(ksecclass): ksecclasskey cfstring,         string(ksecattrapplicationtag): tag cfstring,         ]      let status = secitemcopymatching(query cfdictionary, &keyref)      switch status {     case noerr:         if let ref = keyref {             return (ref as! seckey)         }     default:         break     }      return nil }  func obtainkeydata(_ tag: string) -> data? {     var keyref: anyobject?     let query: dictionary<string, anyobject> = [         string(ksecattrkeytype): ksecattrkeytypersa,         string(ksecreturndata): kcfbooleantrue cfboolean,         string(ksecclass): ksecclasskey cfstring,         string(ksecattrapplicationtag): tag cfstring,         ]      let result: data?      switch secitemcopymatching(query cfdictionary, &keyref) {     case noerr:         result = keyref as? data     default:         result = nil     }      return result }  func insertpublickey(_ publictag: string, data: data) -> seckey? {     let query: dictionary<string, anyobject> = [         string(ksecattrkeytype): ksecattrkeytypersa,         string(ksecclass): ksecclasskey cfstring,         string(ksecattrapplicationtag): publictag cfstring,         string(ksecvaluedata): data cfdata,         string(ksecreturnpersistentref): true cfboolean]      var persistentref: anyobject?     let status = secitemadd(query cfdictionary, &persistentref)      if status != noerr && status != errsecduplicateitem {         return nil     }      return obtainkey(publictag) }  func deletekey(_ tag: string) -> bool {     let query: dictionary<string, anyobject> = [         string(ksecattrkeytype): ksecattrkeytypersa,         string(ksecclass): ksecclasskey cfstring,         string(ksecattrapplicationtag): tag cfstring]      return secitemdelete(query cfdictionary) == noerr }  func updatekey(_ tag: string, data: data) -> bool {     let query: dictionary<string, anyobject> = [         string(ksecattrkeytype): ksecattrkeytypersa,         string(ksecclass): ksecclasskey cfstring,         string(ksecattrapplicationtag): tag cfstring]      return secitemupdate(query cfdictionary, [string(ksecvaluedata): data] cfdictionary) == noerr }