test_security_curve.cpp

/* SPDX-License-Identifier: MPL-2.0 */

// TODO remove this workaround for handling libsodium

//  To define SIZE_MAX with older compilers
#define __STDC_LIMIT_MACROS

#if defined ZMQ_CUSTOM_PLATFORM_HPP
#include "platform.hpp"
#else
#include "../src/platform.hpp"
#endif

#ifndef ZMQ_USE_LIBSODIUM
#define ZMQ_USE_LIBSODIUM
#endif

#include "testutil.hpp"
#include "testutil_security.hpp"
#include <unity.h>

#include "../src/curve_client_tools.hpp"
#include "../src/random.hpp"

char error_message_buffer[256];

void *handler;
void *zap_thread;
void *server;
void *server_mon;
char my_endpoint[MAX_SOCKET_STRING];

void setUp ()
{
    setup_test_context ();
    setup_context_and_server_side (&handler, &zap_thread, &server, &server_mon,
                                   my_endpoint);
}

void tearDown ()
{
    shutdown_context_and_server_side (zap_thread, server, server_mon, handler);
    teardown_test_context ();
}

const int timeout = 250;

const char large_routing_id[] = "0123456789012345678901234567890123456789"
                                "0123456789012345678901234567890123456789"
                                "0123456789012345678901234567890123456789"
                                "0123456789012345678901234567890123456789"
                                "0123456789012345678901234567890123456789"
                                "0123456789012345678901234567890123456789"
                                "012345678901234";

static void zap_handler_large_routing_id (void * /*unused_*/)
{
    zap_handler_generic (zap_ok, large_routing_id);
}

void expect_new_client_curve_bounce_fail (const char *server_public_,
                                          const char *client_public_,
                                          const char *client_secret_,
                                          char *my_endpoint_,
                                          void *server_,
                                          void **client_mon_ = NULL,
                                          int expected_client_event_ = 0,
                                          int expected_client_value_ = 0)
{
    curve_client_data_t curve_client_data = {server_public_, client_public_,
                                             client_secret_};
    expect_new_client_bounce_fail (
      my_endpoint_, server_, socket_config_curve_client, &curve_client_data,
      client_mon_, expected_client_event_, expected_client_value_);
}

void test_null_key (void *server_,
                    void *server_mon_,
                    char *my_endpoint_,
                    char *server_public_,
                    char *client_public_,
                    char *client_secret_)
{
    expect_new_client_curve_bounce_fail (server_public_, client_public_,
                                         client_secret_, my_endpoint_, server_);

    int handshake_failed_encryption_event_count =
      expect_monitor_event_multiple (server_mon_,
                                     ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL,
                                     ZMQ_PROTOCOL_ERROR_ZMTP_CRYPTOGRAPHIC);

    // handshake_failed_encryption_event_count should be at least two because
    // expect_bounce_fail involves two exchanges
    // however, with valgrind we see only one event (maybe the next one takes
    // very long, or does not happen at all because something else takes very
    // long)

    fprintf (stderr,
             "count of "
             "ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL/"
             "ZMQ_PROTOCOL_ERROR_ZMTP_CRYPTOGRAPHIC events: %i\n",
             handshake_failed_encryption_event_count);
}

void test_curve_security_with_valid_credentials ()
{
    curve_client_data_t curve_client_data = {
      valid_server_public, valid_client_public, valid_client_secret};
    void *client_mon;
    void *client = create_and_connect_client (
      my_endpoint, socket_config_curve_client, &curve_client_data, &client_mon);
    bounce (server, client);
    test_context_socket_close (client);

    int event = get_monitor_event_with_timeout (server_mon, NULL, NULL, -1);
    assert (event == ZMQ_EVENT_HANDSHAKE_SUCCEEDED);

    assert_no_more_monitor_events_with_timeout (server_mon, timeout);

    event = get_monitor_event_with_timeout (client_mon, NULL, NULL, -1);
    assert (event == ZMQ_EVENT_HANDSHAKE_SUCCEEDED);

    assert_no_more_monitor_events_with_timeout (client_mon, timeout);

    test_context_socket_close (client_mon);
}

void test_curve_security_with_bogus_client_credentials ()
{
    //  This must be caught by the ZAP handler
    char bogus_public[41];
    char bogus_secret[41];
    zmq_curve_keypair (bogus_public, bogus_secret);

    expect_new_client_curve_bounce_fail (
      valid_server_public, bogus_public, bogus_secret, my_endpoint, server,
      NULL, ZMQ_EVENT_HANDSHAKE_FAILED_AUTH, 400);

    int server_event_count = 0;
    server_event_count = expect_monitor_event_multiple (
      server_mon, ZMQ_EVENT_HANDSHAKE_FAILED_AUTH, 400);
    TEST_ASSERT_LESS_OR_EQUAL_INT (1, server_event_count);

    // there may be more than one ZAP request due to repeated attempts by the client
    TEST_ASSERT (0 == server_event_count
                 || 1 <= zmq_atomic_counter_value (zap_requests_handled));
}

void expect_zmtp_mechanism_mismatch (void *client_,
                                     char *my_endpoint_,
                                     void *server_,
                                     void *server_mon_)
{
    //  This must be caught by the curve_server class, not passed to ZAP
    TEST_ASSERT_SUCCESS_ERRNO (zmq_connect (client_, my_endpoint_));
    expect_bounce_fail (server_, client_);
    test_context_socket_close_zero_linger (client_);

    expect_monitor_event_multiple (server_mon_,
                                   ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL,
                                   ZMQ_PROTOCOL_ERROR_ZMTP_MECHANISM_MISMATCH);

    TEST_ASSERT_EQUAL_INT (0, zmq_atomic_counter_value (zap_requests_handled));
}

void test_curve_security_with_null_client_credentials ()
{
    void *client = test_context_socket (ZMQ_DEALER);

    expect_zmtp_mechanism_mismatch (client, my_endpoint, server, server_mon);
}

void test_curve_security_with_plain_client_credentials ()
{
    void *client = test_context_socket (ZMQ_DEALER);
    TEST_ASSERT_SUCCESS_ERRNO (
      zmq_setsockopt (client, ZMQ_PLAIN_USERNAME, "admin", 5));
    TEST_ASSERT_SUCCESS_ERRNO (
      zmq_setsockopt (client, ZMQ_PLAIN_PASSWORD, "password", 8));

    expect_zmtp_mechanism_mismatch (client, my_endpoint, server, server_mon);
}

void test_curve_security_unauthenticated_message ()
{
    // Unauthenticated messages from a vanilla socket shouldn't be received
    fd_t s = connect_socket (my_endpoint);
    // send anonymous ZMTP/1.0 greeting
    send (s, "\x01\x00", 2, 0);
    // send sneaky message that shouldn't be received
    send (s, "\x08\x00sneaky\0", 9, 0);

    zmq_setsockopt (server, ZMQ_RCVTIMEO, &timeout, sizeof (timeout));
    char *buf = s_recv (server);
    TEST_ASSERT_NULL_MESSAGE (buf, "Received unauthenticated message");
    close (s);
}

void send_all (fd_t fd_, const char *data_, socket_size_t size_)
{
    while (size_ > 0) {
        int res = send (fd_, data_, size_, 0);
        TEST_ASSERT_GREATER_THAN_INT (0, res);
        size_ -= res;
        data_ += res;
    }
}

template <size_t N> void send (fd_t fd_, const char (&data_)[N])
{
    send_all (fd_, data_, N - 1);
}

template <size_t N> void send (fd_t fd_, const uint8_t (&data_)[N])
{
    send_all (fd_, reinterpret_cast<const char *> (&data_), N);
}

void test_curve_security_invalid_hello_wrong_length ()
{
    fd_t s = connect_socket (my_endpoint);

    send (s, zmtp_greeting_curve);

    // send CURVE HELLO of wrong size
    send (s, "\x04\x06\x05HELLO");

    expect_monitor_event_multiple (
      server_mon, ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL,
      ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_HELLO);

    close (s);
}

const size_t hello_length = 200;
const size_t welcome_length = 168;

zmq::curve_client_tools_t make_curve_client_tools ()
{
    uint8_t valid_client_secret_decoded[32];
    uint8_t valid_client_public_decoded[32];

    zmq_z85_decode (valid_client_public_decoded, valid_client_public);
    zmq_z85_decode (valid_client_secret_decoded, valid_client_secret);

    uint8_t valid_server_public_decoded[32];
    zmq_z85_decode (valid_server_public_decoded, valid_server_public);

    return zmq::curve_client_tools_t (valid_client_public_decoded,
                                      valid_client_secret_decoded,
                                      valid_server_public_decoded);
}

// same as htonll, which is only available on few platforms (recent Windows, but not on Linux, e.g.(
static uint64_t host_to_network (uint64_t value_)
{
    // The answer is 42
    static const int num = 42;

    // Check the endianness
    if (*reinterpret_cast<const char *> (&num) == num) {
        const uint32_t high_part = htonl (static_cast<uint32_t> (value_ >> 32));
        const uint32_t low_part =
          htonl (static_cast<uint32_t> (value_ & 0xFFFFFFFFLL));

        return (static_cast<uint64_t> (low_part) << 32) | high_part;
    }
    return value_;
}

template <size_t N> void send_command (fd_t s_, char (&command_)[N])
{
    if (N < 256) {
        send (s_, "\x04");
        char len = (char) N;
        send_all (s_, &len, 1);
    } else {
        send (s_, "\x06");
        uint64_t len = host_to_network (N);
        send_all (s_, reinterpret_cast<char *> (&len), 8);
    }
    send_all (s_, command_, N);
}

void test_curve_security_invalid_hello_command_name ()
{
    fd_t s = connect_socket (my_endpoint);

    send (s, zmtp_greeting_curve);

    zmq::curve_client_tools_t tools = make_curve_client_tools ();

    // send CURVE HELLO with a misspelled command name (but otherwise correct)
    char hello[hello_length];
    TEST_ASSERT_SUCCESS_ERRNO (tools.produce_hello (hello, 0));
    hello[5] = 'X';

    send_command (s, hello);

    expect_monitor_event_multiple (server_mon,
                                   ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL,
                                   ZMQ_PROTOCOL_ERROR_ZMTP_UNEXPECTED_COMMAND);

    close (s);
}

void test_curve_security_invalid_hello_version ()
{
    fd_t s = connect_socket (my_endpoint);

    send (s, zmtp_greeting_curve);

    zmq::curve_client_tools_t tools = make_curve_client_tools ();

    // send CURVE HELLO with a wrong version number (but otherwise correct)
    char hello[hello_length];
    TEST_ASSERT_SUCCESS_ERRNO (tools.produce_hello (hello, 0));
    hello[6] = 2;

    send_command (s, hello);

    expect_monitor_event_multiple (
      server_mon, ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL,
      ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_HELLO);

    close (s);
}

void flush_read (fd_t fd_)
{
    int res;
    char buf[256];

    while ((res = recv (fd_, buf, 256, 0)) == 256) {
    }
    TEST_ASSERT_NOT_EQUAL (-1, res);
}

void recv_all (fd_t fd_, uint8_t *data_, socket_size_t len_)
{
    socket_size_t received = 0;
    while (received < len_) {
        int res = recv (fd_, reinterpret_cast<char *> (data_), len_, 0);
        TEST_ASSERT_GREATER_THAN_INT (0, res);

        data_ += res;
        received += res;
    }
}

void recv_greeting (fd_t fd_)
{
    uint8_t greeting[64];
    recv_all (fd_, greeting, 64);
    //  TODO assert anything about the greeting received from the server?
}

fd_t connect_exchange_greeting_and_send_hello (
  char *my_endpoint_, zmq::curve_client_tools_t &tools_)
{
    fd_t s = connect_socket (my_endpoint_);

    send (s, zmtp_greeting_curve);
    recv_greeting (s);

    // send valid CURVE HELLO
    char hello[hello_length];
    TEST_ASSERT_SUCCESS_ERRNO (tools_.produce_hello (hello, 0));

    send_command (s, hello);
    return s;
}

void test_curve_security_invalid_initiate_wrong_length ()
{
    zmq::curve_client_tools_t tools = make_curve_client_tools ();

    fd_t s = connect_exchange_greeting_and_send_hello (my_endpoint, tools);

    // receive but ignore WELCOME
    flush_read (s);

    int res = get_monitor_event_with_timeout (server_mon, NULL, NULL, timeout);
    TEST_ASSERT_EQUAL_INT (-1, res);

    send (s, "\x04\x09\x08INITIATE");

    expect_monitor_event_multiple (
      server_mon, ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL,
      ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_INITIATE);

    close (s);
}

fd_t connect_exchange_greeting_and_hello_welcome (
  char *my_endpoint_,
  void *server_mon_,
  int timeout_,
  zmq::curve_client_tools_t &tools_)
{
    fd_t s = connect_exchange_greeting_and_send_hello (my_endpoint_, tools_);

    // receive but ignore WELCOME
    uint8_t welcome[welcome_length + 2];
    recv_all (s, welcome, welcome_length + 2);

    uint8_t cn_precom[crypto_box_BEFORENMBYTES];
    TEST_ASSERT_SUCCESS_ERRNO (
      tools_.process_welcome (welcome + 2, welcome_length, cn_precom));

    const int res =
      get_monitor_event_with_timeout (server_mon_, NULL, NULL, timeout_);
    TEST_ASSERT_EQUAL_INT (-1, res);

    return s;
}

void test_curve_security_invalid_initiate_command_name ()
{
    zmq::curve_client_tools_t tools = make_curve_client_tools ();
    fd_t s = connect_exchange_greeting_and_hello_welcome (
      my_endpoint, server_mon, timeout, tools);

    char initiate[257];
    tools.produce_initiate (initiate, 257, 1, NULL, 0);
    // modify command name
    initiate[5] = 'X';

    send_command (s, initiate);

    expect_monitor_event_multiple (server_mon,
                                   ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL,
                                   ZMQ_PROTOCOL_ERROR_ZMTP_UNEXPECTED_COMMAND);

    close (s);
}

void test_curve_security_invalid_initiate_command_encrypted_cookie ()
{
    zmq::curve_client_tools_t tools = make_curve_client_tools ();
    fd_t s = connect_exchange_greeting_and_hello_welcome (
      my_endpoint, server_mon, timeout, tools);

    char initiate[257];
    tools.produce_initiate (initiate, 257, 1, NULL, 0);
    // make garbage from encrypted cookie
    initiate[30] = !initiate[30];

    send_command (s, initiate);

    expect_monitor_event_multiple (server_mon,
                                   ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL,
                                   ZMQ_PROTOCOL_ERROR_ZMTP_CRYPTOGRAPHIC);

    close (s);
}

void test_curve_security_invalid_initiate_command_encrypted_content ()
{
    zmq::curve_client_tools_t tools = make_curve_client_tools ();
    fd_t s = connect_exchange_greeting_and_hello_welcome (
      my_endpoint, server_mon, timeout, tools);

    char initiate[257];
    tools.produce_initiate (initiate, 257, 1, NULL, 0);
    // make garbage from encrypted content
    initiate[150] = !initiate[150];

    send_command (s, initiate);

    expect_monitor_event_multiple (server_mon,
                                   ZMQ_EVENT_HANDSHAKE_FAILED_PROTOCOL,
                                   ZMQ_PROTOCOL_ERROR_ZMTP_CRYPTOGRAPHIC);

    close (s);
}

void test_curve_security_invalid_keysize (void *ctx_)
{
    //  Check return codes for invalid buffer sizes
    void *client = zmq_socket (ctx_, ZMQ_DEALER);
    TEST_ASSERT_NOT_NULL (client);
    errno = 0;
    int rc =
      zmq_setsockopt (client, ZMQ_CURVE_SERVERKEY, valid_server_public, 123);
    assert (rc == -1 && errno == EINVAL);
    errno = 0;
    rc = zmq_setsockopt (client, ZMQ_CURVE_PUBLICKEY, valid_client_public, 123);
    assert (rc == -1 && errno == EINVAL);
    errno = 0;
    rc = zmq_setsockopt (client, ZMQ_CURVE_SECRETKEY, valid_client_secret, 123);
    assert (rc == -1 && errno == EINVAL);
    TEST_ASSERT_SUCCESS_ERRNO (zmq_close (client));
}

// TODO why isn't this const?
char null_key[] = "0000000000000000000000000000000000000000";

void test_null_server_key ()
{
    //  Check CURVE security with a null server key
    //  This will be caught by the curve_server class, not passed to ZAP
    test_null_key (server, server_mon, my_endpoint, null_key,
                   valid_client_public, valid_client_secret);
}

void test_null_client_public_key ()
{
    //  Check CURVE security with a null client public key
    //  This will be caught by the curve_server class, not passed to ZAP
    test_null_key (server, server_mon, my_endpoint, valid_server_public,
                   null_key, valid_client_secret);
}

void test_null_client_secret_key ()
{
    //  Check CURVE security with a null client public key
    //  This will be caught by the curve_server class, not passed to ZAP
    test_null_key (server, server_mon, my_endpoint, valid_server_public,
                   valid_client_public, null_key);
}


int main (void)
{
    if (!zmq_has ("curve")) {
        printf ("CURVE encryption not installed, skipping test\n");
        return 0;
    }

    zmq::random_open ();

    setup_testutil_security_curve ();


    setup_test_environment (180);

    UNITY_BEGIN ();
    RUN_TEST (test_curve_security_with_valid_credentials);
    RUN_TEST (test_null_server_key);
    RUN_TEST (test_null_client_public_key);
    RUN_TEST (test_null_client_secret_key);
    RUN_TEST (test_curve_security_with_bogus_client_credentials);
    RUN_TEST (test_curve_security_with_null_client_credentials);
    RUN_TEST (test_curve_security_with_plain_client_credentials);
    RUN_TEST (test_curve_security_unauthenticated_message);

    //  tests with misbehaving CURVE client
    RUN_TEST (test_curve_security_invalid_hello_wrong_length);
    RUN_TEST (test_curve_security_invalid_hello_command_name);
    RUN_TEST (test_curve_security_invalid_hello_version);
    RUN_TEST (test_curve_security_invalid_initiate_wrong_length);
    RUN_TEST (test_curve_security_invalid_initiate_command_name);
    RUN_TEST (test_curve_security_invalid_initiate_command_encrypted_cookie);
    RUN_TEST (test_curve_security_invalid_initiate_command_encrypted_content);

    // TODO this requires a deviating test setup, must be moved to a separate executable/fixture
    //  test with a large routing id (resulting in large metadata)
    fprintf (stderr,
             "test_curve_security_with_valid_credentials (large routing id)\n");
    setup_test_context ();
    setup_context_and_server_side (&handler, &zap_thread, &server, &server_mon,
                                   my_endpoint, &zap_handler_large_routing_id,
                                   &socket_config_curve_server,
                                   &valid_server_secret, large_routing_id);
    test_curve_security_with_valid_credentials ();
    shutdown_context_and_server_side (zap_thread, server, server_mon, handler);
    teardown_test_context ();

    void *ctx = zmq_ctx_new ();
    test_curve_security_invalid_keysize (ctx);
    TEST_ASSERT_SUCCESS_ERRNO (zmq_ctx_term (ctx));

    zmq::random_close ();

    return UNITY_END ();
}