c – Please be for tomorrow How are passwords generated for each entered name and how is a function created to display the next password to be retrieved?

The program is based on passwords that are automatically generated for each registered user, e.g. For example, answering a bank that generates a password and displays the next password to call … Follow the code below.


struct NO{  
 char dados(100);  
 int senha;  
 struct NO *prox;  
typedef struct NO no;  

int tam;  

int menu(void);  
void inicia(no *FILA);  
void opcao(no *FILA, int op);  
void exibe(no *FILA);  
void exibeSenha(no *FILA);  
void libera(no *FILA);  
void adiciona(no *FILA);  
no *exclui(no *FILA);  

int main(void)  
 no *FILA = (no*) malloc(sizeof(no));  
  printf("Sem memoria disponivel!n");  
 int opt;  


 return 0;  

void inicia(no *FILA)  
 FILA->prox = NULL;  

int menu(void)  
 int opt;  

 printf("nnEscolha a opcaon");  
 printf("0. Sairn");  
 printf("1. Cadastrar novo clienten");  
 printf("2. Exibir lista de clientesn");  
 printf("3, Proxinha senha a ser chamadan");  
 printf("4. Excluir cliente/senhann");  
 printf("Opcao: "); scanf("%d", &opt);  

 return opt;  

void opcao(no *FILA, int op)  
 no *tmp;  
  case 0:  

  case 1:  

  case 2:  

  case 3:  

  case 4:  
   tmp= exclui(FILA);  

   printf("Comando invalidonn");  

int vazia(no *FILA)   
 if(FILA->prox == NULL)  
  return 1;  
  return 0;  

no *aloca()  
 no *novo=(no *) malloc(sizeof(no));  
  printf("Sem memoria disponivel!n");  
  printf("nNovo elemento: "); scanf("%s", &novo->dados);  
  return novo;  

void exibe(no *FILA)  

  printf("FILA vazia!nn");  
  return ;  
 no *tmp;  
 tmp = FILA->prox;     
 while( tmp != NULL){  

  printf("%s - ", tmp->dados);  
  tmp = tmp->prox;  


void exibeSenha (no *FILA) {  
    if(vazia(FILA)) {  
        printf("Sem nenhuma senha cadastrada. Fila vazia!n");  
        return ;  


void libera(no *FILA)  
  no *proxNO,  

  atual = FILA->prox;  
  while(atual != NULL){  
   proxNO = atual->prox;  
   atual = proxNO;  

void adiciona(no *FILA)  
 no *novo=aloca();  
 novo->prox = NULL;  

  no *tmp = FILA->prox;  

  while(tmp->prox != NULL)  
   tmp = tmp->prox;  

  tmp->prox = novo;  

no *exclui(no *FILA)  
 no *ultimo;  
 if(FILA->prox == NULL){  
  printf("FILA ja vaziann");  
  return NULL;  
  no *ultimo = FILA->prox;  

  while(ultimo->prox != NULL){  
   ultimo = ultimo->prox;  

  ultimo->prox = NULL;  
  return ultimo;  

Password – To add Sudo Insults with TouchID without disabling SIP

I follow a tutorial to recompile sudo with insults. However, I was uncomfortable disabling SIP, and I changed it a bit so I can use it with SIP enabled. Sorry, recompiled sudo violated my ability to authenticate sudo with TouchID. I've investigated this and found that it has to do with sudo's code-tagging permissions.

If you look at the permissions for sudo:
sudo cp /usr/bin/sudo . && sudo codesign -d --entitlements :- ./sudo* you get:


Apparently that com.apple.private.AuthorizationServices The key is needed to enable TouchID for sudo.

./sudo ls prompts me to enter TouchID βœ…

sudo codesign --remove-signature ./sudo && sudo -k && ./sudo ls Do not ask me to enter TouchID and just ask for my password ❌

Is that just because I've still enabled SIP? Does disabling SIP remove the TouchID code signature?

* do not do sudo codesign -d --entitlements :- $(which sudo) to expand it to what you will see in a second

Cryptography – Is using a public key to sign in to SSH better than saving a password?

My answer is that using public key pairs is a lot to do wiser thing as with passwords or lists of passwords. I will focus on the things that are not generally known about different forms of SSH authentication, and I do not see any other answers that mention them.

First of all, you have to understand that user authentication is a different and separate process than setting up the user safe channel, For non-experts, this means using the server's public key first (if accepted!) To create the secure SSH channel by enabling the negotiation of a symmetric key used to protect the remaining session and enabling channel is confidentiality, integrity protection and server authentication.

To The channel is functional and safe. The authentication of the user takes place.
The two common methods are using a password or public key pair.
Password-based authentication works the way you expect it to: the client sends its password over the secure channel, and the server verifies that it is actually the user's password and provides access.
In the case of a public key, we have a very different situation. In this case, the public key of the user is stored on the server. Next, the server creates a nonce, encrypts it with the public key and sends it to the user. If the user is the one who should be, he can decrypt the query and send it back to the server, which then confirms the identity of the user. It is the classic Challenge-response model, (SSHv2 actually uses something different, but conceptually close)

As you can imagine, in the first case the password is actually sent to the server (unless SSH would use a password query response), in the second case your private key never leaves the client. In the imaginary scenario that someone can intercept and decrypt SSL traffic (using a compromised private key of the server or if you accept a wrong public key when connecting to the server) or have access to the server or client, enter your password will be known – with the public-private-key authentication and the challenge-response model your private data will never fall into the hands of the attacker.
Even if a server you connect to is compromised, other servers that use the same key will not be affected!

The use of a public key pair offers even more advantages: The private key should not be stored in clear text on your client PC, as you suggest. This will of course allow the private key file to be compromised, as would be the case with an unencrypted password file, but it will be easier to decrypt (at login) and use the private key. It should be kept encodedand you must specify a normally long passphrase to decrypt each time it is used.

Of course, this means that every time you connect to a server, you must enter the long passphrase to unlock your private key. You can enhance the usability of the system by using an authentication agent: software that unlocks your keys for the current session, for example, when you log in to gnome or when you log in to your client for the first time You're remote system ip & # 39; s and log in without specifying a passphrase. Do this several times until you log out of your session.

So, to summarize, The use of public key pairs offers much more protection as with passwords or password lists that can be captured when the client, the server or the secure session is compromised, If no passphrase is used (which should not happen), public key pairs still provide protection against vulnerable sessions and servers.

magento2 – Magento 2 How do I check if the customer changes his password?

You can check / compare the customer's old password and the updated password value using the following code.

encryptor = $encryptor;
        $this->_messageManager = $messageManager;
        $this->objectManager = $objectManager;

    public function execute(MagentoFrameworkEventObserver $observer)
        $customer = $observer->getEvent()->getCustomer();
        $currentPasswordHash = $this->getCurrentPasswordHash($customer->getEntityId());
            $newPasswordHash = $this->encryptor->encrypt("new password value");
            if($currentPasswordHash == $newPasswordHash){
                // password is same
                $this->_messageManager->addWarning(__("New Password is same as current password. Please choose another one"));
        }catch(Exception $e){
            echo 'Error::'.$e->getMessage();

    private function getCurrentPasswordHash($customerId){
        $resource = $this->objectManager->get('MagentoFrameworkAppResourceConnection');
        $connection = $resource->getConnection();
        $sql = "Select password_hash from customer_entity WHERE entity_id = ".$customerId;
        $hash = $connection->fetchOne($sql);
        return $hash;

If you want to use decrypted password values ​​to compare and verify, you can use the following line of code in your Observer.

$decrypt = $this->encryptor->decrypt("password hash");

I hope it helps!!!

Electron Cash Wallet password is not working!

I downloaded the wallet software from electroncash.org, version 2.9.4. I used Shapeshift to transfer some Bitcoins from Coinbase to my new BCH wallet and after a few minutes saw my tokens in order.

Then, 2 days later, when I started the software again, my password did not work!

Can you help me? I received the startup phrase, but how do I use it?
When I start the software, all I have to do is select a wallet default_wallet, I also see the password field just below the pull-down menu to select my wallet. I also tried to enter the start phrase in the password field.