问NSURLCredential在https上安全吗？

EN

- (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge {
NSString *user = you user
NSString *password = you pass;

NSURLCredential *credential = [NSURLCredential credentialWithUser:user
                                                         password:password
                                                      persistence:NSURLCredentialPersistenceForSession];
[[challenge sender] useCredential:credential forAuthenticationChallenge:challenge];

}