libzmq/tests/testutil_security.hpp

/*
    Copyright (c) 2007-2017 Contributors as noted in the AUTHORS file

    This file is part of libzmq, the ZeroMQ core engine in C++.

    libzmq is free software; you can redistribute it and/or modify it under
    the terms of the GNU Lesser General Public License (LGPL) as published
    by the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    As a special exception, the Contributors give you permission to link
    this library with independent modules to produce an executable,
    regardless of the license terms of these independent modules, and to
    copy and distribute the resulting executable under terms of your choice,
    provided that you also meet, for each linked independent module, the
    terms and conditions of the license of that module. An independent
    module is a module which is not derived from or based on this library.
    If you modify this library, you must extend this exception to your
    version of the library.

    libzmq is distributed in the hope that it will be useful, but WITHOUT
    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
    License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef __TESTUTIL_SECURITY_HPP_INCLUDED__
#define __TESTUTIL_SECURITY_HPP_INCLUDED__

#include "testutil.hpp"

//  security test utils

typedef void(socket_config_fn) (void *, void *);

const char *test_zap_domain = "ZAPTEST";

//  NULL specific functions
void socket_config_null_client (void *server, void *server_secret)
{
}

void socket_config_null_server (void *server, void *server_secret)
{
    int rc = zmq_setsockopt (server, ZMQ_ZAP_DOMAIN, test_zap_domain, 7);
    assert (rc == 0);
}

//  CURVE specific functions

//  We'll generate random test keys at startup
char valid_client_public[41];
char valid_client_secret[41];
char valid_server_public[41];
char valid_server_secret[41];

void setup_testutil_security_curve ()
{
    //  Generate new keypairs for these tests
    int rc = zmq_curve_keypair (valid_client_public, valid_client_secret);
    assert (rc == 0);
    rc = zmq_curve_keypair (valid_server_public, valid_server_secret);
    assert (rc == 0);
}

void socket_config_curve_server (void *server, void *server_secret)
{
    int as_server = 1;
    int rc = zmq_setsockopt (server, ZMQ_CURVE_SERVER, &as_server, sizeof (int));
    assert (rc == 0);

    rc = zmq_setsockopt (server, ZMQ_CURVE_SECRETKEY, server_secret, 41);
    assert (rc == 0);
}

struct curve_client_data_t
{
    const char *server_public;
    const char *client_public;
    const char *client_secret;
};

void socket_config_curve_client (void *client, void *data)
{
    curve_client_data_t *curve_client_data =
      static_cast<curve_client_data_t *> (data);

    int rc = zmq_setsockopt (client, ZMQ_CURVE_SERVERKEY,
                             curve_client_data->server_public, 41);
    assert (rc == 0);
    rc = zmq_setsockopt (client, ZMQ_CURVE_PUBLICKEY,
                         curve_client_data->client_public, 41);
    assert (rc == 0);
    rc = zmq_setsockopt (client, ZMQ_CURVE_SECRETKEY,
                         curve_client_data->client_secret, 41);
    assert (rc == 0);
}

//  --------------------------------------------------------------------------
//  This methods receives and validates ZAP requests (allowing or denying
//  each client connection).

enum zap_protocol_t
{
  zap_ok,
  // ZAP-compliant non-standard cases
  zap_status_temporary_failure,
  zap_status_internal_error,
  // ZAP protocol errors
  zap_wrong_version,
  zap_wrong_request_id,
  zap_status_invalid,
  zap_too_many_parts
};

void *zap_requests_handled;

void zap_handler_generic (void *ctx,
                          zap_protocol_t zap_protocol,
                          const char *expected_identity = "IDENT")
{
    void *control = zmq_socket (ctx, ZMQ_REQ);
    assert (control);
    int rc = zmq_connect (control, "inproc://handler-control");
    assert (rc == 0);

    void *handler = zmq_socket (ctx, ZMQ_REP);
    assert (handler);
    rc = zmq_bind (handler, "inproc://zeromq.zap.01");
    assert (rc == 0);

    //  Signal main thread that we are ready
    rc = s_send (control, "GO");
    assert (rc == 2);

    zmq_pollitem_t items[] = {
      {control, 0, ZMQ_POLLIN, 0}, {handler, 0, ZMQ_POLLIN, 0},
    };

    //  Process ZAP requests forever
    while (zmq_poll (items, 2, -1) >= 0) {
        if (items[0].revents & ZMQ_POLLIN) {
            char *buf = s_recv (control);
            assert (buf);
            assert (streq (buf, "STOP"));
            free (buf);
            break; //  Terminating - main thread signal
        }
        if (!(items[1].revents & ZMQ_POLLIN))
            continue;

        char *version = s_recv (handler);
        if (!version)
            break; //  Terminating - peer's socket closed

        char *sequence = s_recv (handler);
        char *domain = s_recv (handler);
        char *address = s_recv (handler);
        char *identity = s_recv (handler);
        char *mechanism = s_recv (handler);
        bool authentication_succeeded = false;
        if (streq (mechanism, "CURVE")) {
            uint8_t client_key[32];
            int size = zmq_recv (handler, client_key, 32, 0);
            assert (size == 32);

            char client_key_text[41];
            zmq_z85_encode (client_key_text, client_key, 32);

            authentication_succeeded =
              streq (client_key_text, valid_client_public);
        }
        else if (streq(mechanism, "PLAIN"))
        {
          // TODO
          authentication_succeeded = true;
        }
        else if (streq(mechanism, "NULL"))
        {
          authentication_succeeded = true;
        }
        else
        {
            fprintf (stderr, "Unsupported mechanism: %s\n", mechanism);
            assert (false);
        }

        assert (streq (version, "1.0"));
        assert (streq (identity, expected_identity));

        s_sendmore (handler, zap_protocol == zap_wrong_version
                               ? "invalid_version"
                               : version);
        s_sendmore (handler, zap_protocol == zap_wrong_request_id
                               ? "invalid_request_id"
                               : sequence);

        if (authentication_succeeded) {
            const char *status_code;
            switch (zap_protocol) {
                case zap_status_internal_error:
                    status_code = "500";
                    break;
                case zap_status_temporary_failure:
                    status_code = "300";
                    break;
                case zap_status_invalid:
                    status_code = "invalid_status";
                    break;
                default:
                    status_code = "200";
            }
            s_sendmore (handler, status_code);
            s_sendmore (handler, "OK");
            s_sendmore (handler, "anonymous");
            if (zap_protocol == zap_too_many_parts) {
                s_sendmore (handler, "");
            }
            s_send (handler, "");
        } else {
            s_sendmore (handler, "400");
            s_sendmore (handler, "Invalid client public key");
            s_sendmore (handler, "");
            s_send (handler, "");
        }
        free (version);
        free (sequence);
        free (domain);
        free (address);
        free (identity);
        free (mechanism);

        zmq_atomic_counter_inc (zap_requests_handled);
    }
    rc = zmq_unbind (handler, "inproc://zeromq.zap.01");
    assert (rc == 0);
    close_zero_linger (handler);

    rc = s_send (control, "STOPPED");
    assert (rc == 7);
    close_zero_linger (control);
}

void zap_handler (void *ctx)
{
    zap_handler_generic (ctx, zap_ok);
}

void setup_context_and_server_side (
  void **ctx,
  void **handler,
  void **zap_thread,
  void **server,
  void **server_mon,
  char *my_endpoint,
  zmq_thread_fn zap_handler_ = &zap_handler,
  socket_config_fn socket_config_ = &socket_config_curve_server,
  void *socket_config_data_ = valid_server_secret,
  const char *identity = "IDENT")
{
    *ctx = zmq_ctx_new ();
    assert (*ctx);

    //  Spawn ZAP handler
    zap_requests_handled = zmq_atomic_counter_new ();
    assert (zap_requests_handled != NULL);

    *handler = zmq_socket (*ctx, ZMQ_REP);
    assert (*handler);
    int rc = zmq_bind (*handler, "inproc://handler-control");
    assert (rc == 0);

    *zap_thread = zmq_threadstart (zap_handler_, *ctx);

    char *buf = s_recv (*handler);
    assert (buf);
    assert (streq (buf, "GO"));
    free (buf);

    //  Server socket will accept connections
    *server = zmq_socket (*ctx, ZMQ_DEALER);
    assert (*server);

    socket_config_ (*server, socket_config_data_);

    rc = zmq_setsockopt (*server, ZMQ_IDENTITY, identity, strlen(identity));
    assert (rc == 0);

    rc = zmq_bind (*server, "tcp://127.0.0.1:*");
    assert (rc == 0);

    size_t len = MAX_SOCKET_STRING;
    rc = zmq_getsockopt (*server, ZMQ_LAST_ENDPOINT, my_endpoint, &len);
    assert (rc == 0);

#ifdef ZMQ_BUILD_DRAFT_API
    char monitor_endpoint [] = "inproc://monitor-server";

    //  Monitor handshake events on the server
    rc = zmq_socket_monitor (
      *server, monitor_endpoint,
      ZMQ_EVENT_HANDSHAKE_SUCCEEDED | ZMQ_EVENT_HANDSHAKE_FAILED_NO_DETAIL
        | ZMQ_EVENT_HANDSHAKE_FAILED_ZAP | ZMQ_EVENT_HANDSHAKE_FAILED_ZMTP
        | ZMQ_EVENT_HANDSHAKE_FAILED_ENCRYPTION);
    assert (rc == 0);

    //  Create socket for collecting monitor events
    *server_mon = zmq_socket (*ctx, ZMQ_PAIR);
    assert (*server_mon);

    //  Connect it to the inproc endpoints so they'll get events
    rc = zmq_connect (*server_mon, monitor_endpoint);
    assert (rc == 0);
#endif
}

void shutdown_context_and_server_side (void *ctx,
                                       void *zap_thread,
                                       void *server,
                                       void *server_mon,
                                       void *handler)
{
    int rc = s_send (handler, "STOP");
    assert (rc == 4);
    char *buf = s_recv (handler);
    assert (buf);
    assert (streq (buf, "STOPPED"));
    free (buf);
    rc = zmq_unbind (handler, "inproc://handler-control");
    assert (rc == 0);
    close_zero_linger (handler);

#ifdef ZMQ_BUILD_DRAFT_API
    close_zero_linger (server_mon);
#endif
    close_zero_linger (server);

    //  Wait until ZAP handler terminates
    zmq_threadclose (zap_thread);

    rc = zmq_ctx_term (ctx);
    assert (rc == 0);

    zmq_atomic_counter_destroy (&zap_requests_handled);
}

void *create_and_connect_client (void *ctx,
                                 char *my_endpoint,
                                 socket_config_fn socket_config_,
                                 void *socket_config_data_)
{
    void *client = zmq_socket (ctx, ZMQ_DEALER);
    assert (client);

    socket_config_ (client, socket_config_data_);

    int rc = zmq_connect (client, my_endpoint);
    assert (rc == 0);

    return client;
}

void expect_new_client_bounce_fail (void *ctx,
                                    char *my_endpoint,
                                    void *server,
                                    socket_config_fn socket_config_,
                                    void *socket_config_data_)
{
    void *client = create_and_connect_client (ctx, my_endpoint, socket_config_,
                                              socket_config_data_);
    expect_bounce_fail (server, client);
    close_zero_linger (client);
}

//  Monitor event utilities

//  Read one event off the monitor socket; return value and address
//  by reference, if not null, and event number by value. Returns -1
//  in case of error.

static int
get_monitor_event_internal (void *monitor, int *value, char **address, int recv_flag)
{
    //  First frame in message contains event number and value
    zmq_msg_t msg;
    zmq_msg_init (&msg);
    if (zmq_msg_recv (&msg, monitor, recv_flag) == -1) {
        assert (errno == EAGAIN);
        return -1; //  timed out or no message available
    }
    assert (zmq_msg_more (&msg));

    uint8_t *data = (uint8_t *) zmq_msg_data (&msg);
    uint16_t event = *(uint16_t *) (data);
    if (value)
        *value = *(uint32_t *) (data + 2);

    //  Second frame in message contains event address
    zmq_msg_init (&msg);
    int res = zmq_msg_recv (&msg, monitor, recv_flag) == -1;
    assert (res != -1);
    assert (!zmq_msg_more (&msg));

    if (address) {
        uint8_t *data = (uint8_t *) zmq_msg_data (&msg);
        size_t size = zmq_msg_size (&msg);
        *address = (char *) malloc (size + 1);
        memcpy (*address, data, size);
        *address [size] = 0;
    }
    return event;
}

int get_monitor_event_with_timeout (void *monitor,
                                    int *value,
                                    char **address,
                                    int timeout)
{
    int res;
    if (timeout == -1) {
        // process infinite timeout in small steps to allow the user
        // to see some information on the console

        int timeout_step = 250;
        int wait_time = 0;
        zmq_setsockopt (monitor, ZMQ_RCVTIMEO, &timeout_step,
                        sizeof (timeout_step));
        while ((res = get_monitor_event_internal (monitor, value, address, 0))
               == -1) {
            wait_time += timeout_step;
            fprintf (stderr, "Still waiting for monitor event after %i ms\n",
                     wait_time);
        }
    } else {
        zmq_setsockopt (monitor, ZMQ_RCVTIMEO, &timeout, sizeof (timeout));
        res = get_monitor_event_internal (monitor, value, address, 0);
    }
    int timeout_infinite = -1;
    zmq_setsockopt (monitor, ZMQ_RCVTIMEO, &timeout_infinite,
                    sizeof (timeout_infinite));
    return res;
}

#ifdef ZMQ_BUILD_DRAFT_API
//  expects that one or more occurrences of the expected event are received 
//  via the specified socket monitor
//  returns the number of occurrences of the expected event
//  interrupts, if a ZMQ_EVENT_HANDSHAKE_FAILED_NO_DETAIL with EPIPE, ECONNRESET
//  or ECONNABORTED occurs; in this case, 0 is returned
//  this should be investigated further, see 
//  https://github.com/zeromq/libzmq/issues/2644
int expect_monitor_event_multiple (void *server_mon,
                                   int expected_event,
                                   int expected_err = -1)
{
    int count_of_expected_events = 0;
    int client_closed_connection = 0;
    //  infinite timeout at the start
    int timeout = -1;

    int event;
    int err;
    while (
      (event = get_monitor_event_with_timeout (server_mon, &err, NULL, timeout))
      != -1) {
        timeout = 250;

        // ignore errors with EPIPE/ECONNRESET/ECONNABORTED, which can happen
        // ECONNRESET can happen on very slow machines, when the engine writes
        // to the peer and then tries to read the socket before the peer reads
        // ECONNABORTED happens when a client aborts a connection via RST/timeout
        if (event == ZMQ_EVENT_HANDSHAKE_FAILED_NO_DETAIL &&
                (err == EPIPE || err == ECONNRESET || err == ECONNABORTED)) {
            fprintf (
              stderr,
              "Ignored event (skipping any further events): %x (err = %i)\n",
              event, err);
            client_closed_connection = 1;
            break;
        }
        if (event != expected_event
            || (-1 != expected_err && err != expected_err)) {
            fprintf (stderr, "Unexpected event: %x (err = %i)\n", event, err);
            assert (false);
        }
        ++count_of_expected_events;
    }
    assert (count_of_expected_events > 0 || client_closed_connection);

    return count_of_expected_events;
}
#endif

#endif