null_mechanism.cpp 7.01 KB
Newer Older
1
/*
2
    Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
3

4
    This file is part of libzmq, the ZeroMQ core engine in C++.
5

6 7 8
    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
9 10
    (at your option) any later version.

11 12 13 14 15 16 17 18 19 20 21 22 23 24
    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.
25 26 27 28 29

    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/>.
*/

30
#include "precompiled.hpp"
31 32 33 34 35 36 37

#include <stddef.h>
#include <string.h>
#include <stdlib.h>

#include "err.hpp"
#include "msg.hpp"
38
#include "session_base.hpp"
39 40 41
#include "wire.hpp"
#include "null_mechanism.hpp"

42 43 44
zmq::null_mechanism_t::null_mechanism_t (session_base_t *session_,
                                         const std::string &peer_address_,
                                         const options_t &options_) :
45
    mechanism_base_t (session_, options_),
46
    zap_client_t (session_, peer_address_, options_),
47
    ready_command_sent (false),
48
    error_command_sent (false),
49
    ready_command_received (false),
50
    error_command_received (false),
51 52
    zap_request_sent (false),
    zap_reply_received (false)
53 54 55 56 57 58 59
{
}

zmq::null_mechanism_t::~null_mechanism_t ()
{
}

60
int zmq::null_mechanism_t::next_handshake_command (msg_t *msg_)
61
{
62
    if (ready_command_sent || error_command_sent) {
63 64 65
        errno = EAGAIN;
        return -1;
    }
66

67
    if (zap_required () && !zap_reply_received) {
68 69 70 71
        if (zap_request_sent) {
            errno = EAGAIN;
            return -1;
        }
72 73
        //  Given this is a backward-incompatible change, it's behind a socket
        //  option disabled by default.
74
        int rc = session->zap_connect ();
75
        if (rc == -1 && options.zap_enforce_domain) {
76 77
            session->get_socket ()->event_handshake_failed_no_detail (
              session->get_endpoint (), EFAULT);
78
            return -1;
79 80 81 82 83 84 85 86 87 88 89 90 91
        } else if (rc == 0) {
            send_zap_request ();
            zap_request_sent = true;

            //  TODO actually, it is quite unlikely that we can read the ZAP
            //  reply already, but removing this has some strange side-effect
            //  (probably because the pipe's in_active flag is true until a read
            //  is attempted)
            rc = receive_and_process_zap_reply ();
            if (rc != 0)
                return -1;

            zap_reply_received = true;
92
        }
93
    }
94

95
    if (zap_reply_received && status_code != "200") {
96
        error_command_sent = true;
97 98 99 100 101 102 103 104 105 106 107 108 109 110
        if (status_code != "300") {
            const size_t status_code_len = 3;
            const int rc = msg_->init_size (6 + 1 + status_code_len);
            zmq_assert (rc == 0);
            unsigned char *msg_data =
              static_cast<unsigned char *> (msg_->data ());
            memcpy (msg_data, "\5ERROR", 6);
            msg_data[6] = status_code_len;
            memcpy (msg_data + 7, status_code.c_str (), status_code_len);
            return 0;
        } else {
            errno = EAGAIN;
            return -1;
        }
111 112
    }

113
    make_command_with_basic_properties (msg_, "\5READY", 6);
114 115 116 117 118 119

    ready_command_sent = true;

    return 0;
}

120
int zmq::null_mechanism_t::process_handshake_command (msg_t *msg_)
121
{
122
    if (ready_command_received || error_command_received) {
123
        session->get_socket ()->event_handshake_failed_protocol (
124
          session->get_endpoint (), ZMQ_PROTOCOL_ERROR_ZMTP_UNEXPECTED_COMMAND);
125 126 127 128
        errno = EPROTO;
        return -1;
    }

129
    const unsigned char *cmd_data =
130
      static_cast<unsigned char *> (msg_->data ());
131
    const size_t data_size = msg_->size ();
132

133 134 135
    int rc = 0;
    if (data_size >= 6 && !memcmp (cmd_data, "\5READY", 6))
        rc = process_ready_command (cmd_data, data_size);
136
    else if (data_size >= 6 && !memcmp (cmd_data, "\5ERROR", 6))
137 138
        rc = process_error_command (cmd_data, data_size);
    else {
139
        session->get_socket ()->event_handshake_failed_protocol (
140
          session->get_endpoint (), ZMQ_PROTOCOL_ERROR_ZMTP_UNEXPECTED_COMMAND);
141
        errno = EPROTO;
142
        rc = -1;
143 144
    }

145
    if (rc == 0) {
146
        rc = msg_->close ();
147 148 149
        errno_assert (rc == 0);
        rc = msg_->init ();
        errno_assert (rc == 0);
150
    }
151 152
    return rc;
}
153

154 155
int zmq::null_mechanism_t::process_ready_command (const unsigned char *cmd_data,
                                                  size_t data_size)
156
{
157
    ready_command_received = true;
158 159
    return parse_metadata (cmd_data + 6, data_size - 6);
}
160

161 162
int zmq::null_mechanism_t::process_error_command (const unsigned char *cmd_data,
                                                  size_t data_size)
163
{
164
    if (data_size < 7) {
165 166 167 168
        session->get_socket ()->event_handshake_failed_protocol (
          session->get_endpoint (),
          ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_ERROR);

169 170 171
        errno = EPROTO;
        return -1;
    }
172
    const size_t error_reason_len = static_cast<size_t> (cmd_data[6]);
173
    if (error_reason_len > data_size - 7) {
174 175 176 177
        session->get_socket ()->event_handshake_failed_protocol (
          session->get_endpoint (),
          ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_ERROR);

178 179 180
        errno = EPROTO;
        return -1;
    }
181 182
    const char *error_reason = reinterpret_cast<const char *> (cmd_data) + 7;
    handle_error_reason (error_reason, error_reason_len);
183
    error_command_received = true;
184
    return 0;
185 186
}

187 188 189 190 191 192 193 194 195
int zmq::null_mechanism_t::zap_msg_available ()
{
    if (zap_reply_received) {
        errno = EFSM;
        return -1;
    }
    const int rc = receive_and_process_zap_reply ();
    if (rc == 0)
        zap_reply_received = true;
196
    return rc == -1 ? -1 : 0;
197 198
}

199
zmq::mechanism_t::status_t zmq::null_mechanism_t::status () const
200
{
201
    const bool command_sent = ready_command_sent || error_command_sent;
202
    const bool command_received =
203
      ready_command_received || error_command_received;
204 205

    if (ready_command_sent && ready_command_received)
206
        return mechanism_t::ready;
207
    else if (command_sent && command_received)
208 209 210
        return error;
    else
        return handshaking;
211
}
212

213
void zmq::null_mechanism_t::send_zap_request ()
214
{
215
    zap_client_t::send_zap_request ("NULL", 4, NULL, NULL, 0);
216
}