text: /*
   * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
   *
   * Licensed under the Apache License, Version 2.0 (the "License").
   * You may not use this file except in compliance with the License.
   * A copy of the License is located at
   *
   *  http://aws.amazon.com/apache2.0
   *
   * or in the "license" file accompanying this file. This file is distributed
   * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
   * express or implied. See the License for the specific language governing
   * permissions and limitations under the License.
   */
  
  #include "s2n_test.h"
  
  #include "testlib/s2n_testlib.h"
  
  #include <unistd.h>
  #include <stdint.h>
  
  #include "api/s2n.h"
  
  #define ZERO_TO_THIRTY_ONE  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, \
                              0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F
  
  #define INTERNAL_ERROR_ALERT_HEX 0x50
  
  /* This test simulates a client sends a TLS alert record and closes its socket immediately after the ClientHello.
   * We want to validate that s2n informs the caller of the alert instead of an I/O error. Both errors result
   * in a failed handshake, but the alert is generally more useful.
   */
  
  int main(int argc, char **argv)
  {
      BEGIN_TEST();
      EXPECT_SUCCESS(s2n_disable_tls13());
      uint8_t client_hello_message[] = {
          /* Protocol version TLS 1.2 */
          0x03, 0x03,
          /* Client random */
          ZERO_TO_THIRTY_ONE,
          /* SessionID len - 32 bytes */
          0x20,
          /* Session ID */
          ZERO_TO_THIRTY_ONE,
          /* Cipher suites len */
          0x00, 0x02,
          /* Cipher suite - TLS_RSA_WITH_AES_128_CBC_SHA256 */
          0x00, 0x3C,
          /* Compression methods len */
          0x01,
          /* Compression method - none */
          0x00,
          /* Extensions len */
          0x00, 0x00
      };
      size_t body_len = sizeof(client_hello_message);
      uint8_t message_header[] = {
          /* Handshake message type CLIENT HELLO */
          0x01,
          /* Body len */
          (body_len >> 16) & 0xff, (body_len >> 8) & 0xff, (body_len & 0xff),
      };
      size_t message_len = sizeof(message_header) + body_len;
      uint8_t record_header[] = {
          /* Record type HANDSHAKE */
          0x16,
          /* Protocol version TLS 1.2 */
          0x03, 0x03,
          /* Message len */
          (message_len >> 8) & 0xff, (message_len & 0xff),
      };
  
      uint8_t alert_record[] = {
          /* Record type ALERT */
          0x15,
          /* Protocol version TLS 1.2 */
          0x03, 0x03,
          /* Length */
          0x00, 0x02,
          /* Fatal alert "internal_error" */
          0x02, INTERNAL_ERROR_ALERT_HEX,
      };
  
      struct s2n_connection *server_conn;
      struct s2n_config *server_config;
      s2n_blocked_status server_blocked;
      char *cert_chain = malloc(S2N_MAX_TEST_PEM_SIZE);
      char *private_key = malloc(S2N_MAX_TEST_PEM_SIZE);
      struct s2n_cert_chain_and_key *chain_and_key;
  
      struct s2n_test_io_pair io_pair;
      EXPECT_SUCCESS(s2n_io_pair_init_non_blocking(&io_pair));
  
      EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
      EXPECT_SUCCESS(s2n_connection_set_io_pair(server_conn, &io_pair));
  
      EXPECT_NOT_NULL(server_config = s2n_config_new());
      EXPECT_SUCCESS(s2n_read_test_pem(S2N_DEFAULT_TEST_CERT_CHAIN, cert_chain, S2N_MAX_TEST_PEM_SIZE));
      EXPECT_SUCCESS(s2n_read_test_pem(S2N_DEFAULT_TEST_PRIVATE_KEY, private_key, S2N_MAX_TEST_PEM_SIZE));
      EXPECT_NOT_NULL(chain_and_key = s2n_cert_chain_and_key_new());
      EXPECT_SUCCESS(s2n_cert_chain_and_key_load_pem(chain_and_key, cert_chain, private_key));
      EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(server_config, chain_and_key));
      EXPECT_SUCCESS(s2n_connection_set_config(server_conn, server_config));
  
      /* Send the client hello */
      EXPECT_EQUAL(write(io_pair.client, record_header, sizeof(record_header)), sizeof(record_header));
      EXPECT_EQUAL(write(io_pair.client, message_header, sizeof(message_header)), sizeof(message_header));
      EXPECT_EQUAL(write(io_pair.client, client_hello_message, sizeof(client_hello_message)), sizeof(client_hello_message));
  
      /* Send an alert from client to server */
      EXPECT_EQUAL(write(io_pair.client, alert_record, sizeof(alert_record)), sizeof(alert_record));
  
      /* Close the client read/write end */
      EXPECT_SUCCESS(s2n_io_pair_close_one_end(&io_pair, S2N_CLIENT));
  
      /* Expect the server to fail due to an incoming alert. We should not fail due to an I/O error(EPIPE). */
      s2n_negotiate(server_conn, &server_blocked);
      EXPECT_EQUAL(s2n_error_get_type(s2n_errno), S2N_ERR_T_ALERT);
      EXPECT_EQUAL(s2n_connection_get_alert(server_conn), INTERNAL_ERROR_ALERT_HEX);
  
      EXPECT_SUCCESS(s2n_connection_free(server_conn));
      EXPECT_SUCCESS(s2n_cert_chain_and_key_free(chain_and_key));
      EXPECT_SUCCESS(s2n_config_free(server_config));
      free(cert_chain);
      free(private_key);
  
      EXPECT_SUCCESS(s2n_io_pair_close_one_end(&io_pair, S2N_SERVER));
  
      END_TEST();
  }
  