/* Enumerate the PC ranges covered by a DIE. Copyright (C) 2005, 2007, 2009 Red Hat, Inc. This file is part of elfutils. This file is free software; you can redistribute it and/or modify it under the terms of either * the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version or * the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version or both in parallel, as here. elfutils 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 General Public License for more details. You should have received copies of the GNU General Public License and the GNU Lesser General Public License along with this program. If not, see . */ #ifdef HAVE_CONFIG_H # include #endif #include "libdwP.h" #include #include /* Read up begin/end pair and increment read pointer. - If it's normal range record, set up `*beginp' and `*endp' and return 0. - If it's base address selection record, set up `*basep' and return 1. - If it's end of rangelist, don't set anything and return 2 - If an error occurs, don't set anything and return -1. */ internal_function int __libdw_read_begin_end_pair_inc (Dwarf *dbg, int sec_index, unsigned char **addrp, int width, Dwarf_Addr *beginp, Dwarf_Addr *endp, Dwarf_Addr *basep) { Dwarf_Addr escape = (width == 8 ? (Elf64_Addr) -1 : (Elf64_Addr) (Elf32_Addr) -1); Dwarf_Addr begin; Dwarf_Addr end; unsigned char *addr = *addrp; bool begin_relocated = READ_AND_RELOCATE (__libdw_relocate_address, begin); bool end_relocated = READ_AND_RELOCATE (__libdw_relocate_address, end); *addrp = addr; /* Unrelocated escape for begin means base address selection. */ if (begin == escape && !begin_relocated) { if (unlikely (end == escape)) { __libdw_seterrno (DWARF_E_INVALID_DWARF); return -1; } if (basep != NULL) *basep = end; return 1; } /* Unrelocated pair of zeroes means end of range list. */ if (begin == 0 && end == 0 && !begin_relocated && !end_relocated) return 2; /* Don't check for begin_relocated == end_relocated. Serve the data to the client even though it may be buggy. */ *beginp = begin; *endp = end; return 0; } ptrdiff_t dwarf_ranges (Dwarf_Die *die, ptrdiff_t offset, Dwarf_Addr *basep, Dwarf_Addr *startp, Dwarf_Addr *endp) { if (die == NULL) return -1; if (offset == 0 /* Usually there is a single contiguous range. */ && INTUSE(dwarf_highpc) (die, endp) == 0 && INTUSE(dwarf_lowpc) (die, startp) == 0) /* A offset into .debug_ranges will never be 1, it must be at least a multiple of 4. So we can return 1 as a special case value to mark there are no ranges to look for on the next call. */ return 1; if (offset == 1) return 0; /* We have to look for a noncontiguous range. */ const Elf_Data *d = die->cu->dbg->sectiondata[IDX_debug_ranges]; if (d == NULL && offset != 0) { __libdw_seterrno (DWARF_E_NO_DEBUG_RANGES); return -1; } unsigned char *readp; unsigned char *readendp; if (offset == 0) { Dwarf_Attribute attr_mem; Dwarf_Attribute *attr = INTUSE(dwarf_attr) (die, DW_AT_ranges, &attr_mem); if (attr == NULL) /* No PC attributes in this DIE at all, so an empty range list. */ return 0; Dwarf_Word start_offset; if ((readp = __libdw_formptr (attr, IDX_debug_ranges, DWARF_E_NO_DEBUG_RANGES, &readendp, &start_offset)) == NULL) return -1; offset = start_offset; assert ((Dwarf_Word) offset == start_offset); /* Fetch the CU's base address. */ Dwarf_Die cudie = CUDIE (attr->cu); /* Find the base address of the compilation unit. It will normally be specified by DW_AT_low_pc. In DWARF-3 draft 4, the base address could be overridden by DW_AT_entry_pc. It's been removed, but GCC emits DW_AT_entry_pc and not DW_AT_lowpc for compilation units with discontinuous ranges. */ if (unlikely (INTUSE(dwarf_lowpc) (&cudie, basep) != 0) && INTUSE(dwarf_formaddr) (INTUSE(dwarf_attr) (&cudie, DW_AT_entry_pc, &attr_mem), basep) != 0) *basep = (Dwarf_Addr) -1; } else { if (__libdw_offset_in_section (die->cu->dbg, IDX_debug_ranges, offset, 1)) return -1l; readp = d->d_buf + offset; readendp = d->d_buf + d->d_size; } next: if (readendp - readp < die->cu->address_size * 2) goto invalid; Dwarf_Addr begin; Dwarf_Addr end; switch (__libdw_read_begin_end_pair_inc (die->cu->dbg, IDX_debug_ranges, &readp, die->cu->address_size, &begin, &end, basep)) { case 0: break; case 1: goto next; case 2: return 0; default: return -1l; } /* We have an address range entry. Check that we have a base. */ if (*basep == (Dwarf_Addr) -1) { if (INTUSE(dwarf_errno) () == 0) { invalid: __libdw_seterrno (DWARF_E_INVALID_DWARF); } return -1; } *startp = *basep + begin; *endp = *basep + end; return readp - (unsigned char *) d->d_buf; } INTDEF (dwarf_ranges) it/qt/qtbase.git/tree/examples/network/secureudpserver?id=f140ef04a0c54c2c8a699db33433b8d7235d137c'>secureudpserver/server.cpp
blob: 450eb9e68d24181587906d5bed95595b3b453314 (plain) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276

/****************************************************************************
**
** Copyright (C) 2018 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "server.h"

#include <algorithm>

QT_BEGIN_NAMESPACE

namespace {

QString peer_info(const QHostAddress &address, quint16 port)
{
    const static QString info = QStringLiteral("(%1:%2)");
    return info.arg(address.toString()).arg(port);
}

QString connection_info(QDtls *connection)
{
    QString info(DtlsServer::tr("Session cipher: "));
    info += connection->sessionCipher().name();

    info += DtlsServer::tr("; session protocol: ");
    switch (connection->sessionProtocol()) {
    case QSsl::DtlsV1_0:
        info += DtlsServer::tr("DTLS 1.0.");
        break;
    case QSsl::DtlsV1_2:
        info += DtlsServer::tr("DTLS 1.2.");
        break;
    case QSsl::DtlsV1_2OrLater:
        info += DtlsServer::tr("DTLS 1.2 or later.");
        break;
    default:
        info += DtlsServer::tr("Unknown protocol.");
    }

    return info;
}

} // unnamed namespace

//! [1]
DtlsServer::DtlsServer()
{
    connect(&serverSocket, &QAbstractSocket::readyRead, this, &DtlsServer::readyRead);

    serverConfiguration = QSslConfiguration::defaultDtlsConfiguration();
    serverConfiguration.setPreSharedKeyIdentityHint("Qt DTLS example server");
    serverConfiguration.setPeerVerifyMode(QSslSocket::VerifyNone);
}
//! [1]

DtlsServer::~DtlsServer()
{
    shutdown();
}

//! [2]
bool DtlsServer::listen(const QHostAddress &address, quint16 port)
{
    if (address != serverSocket.localAddress() || port != serverSocket.localPort()) {
        shutdown();
        listening = serverSocket.bind(address, port);
        if (!listening)
            emit errorMessage(serverSocket.errorString());
    } else {
        listening = true;
    }

    return listening;
}
//! [2]

bool DtlsServer::isListening() const
{
    return listening;
}

void DtlsServer::close()
{
    listening = false;
}

void DtlsServer::readyRead()
{
    //! [3]
    const qint64 bytesToRead = serverSocket.pendingDatagramSize();
    if (bytesToRead <= 0) {
        emit warningMessage(tr("A spurious read notification"));
        return;
    }

    QByteArray dgram(bytesToRead, Qt::Uninitialized);
    QHostAddress peerAddress;
    quint16 peerPort = 0;
    const qint64 bytesRead = serverSocket.readDatagram(dgram.data(), dgram.size(),
                                                       &peerAddress, &peerPort);
    if (bytesRead <= 0) {
        emit warningMessage(tr("Failed to read a datagram: ") + serverSocket.errorString());
        return;
    }

    dgram.resize(bytesRead);
    //! [3]
    //! [4]
    if (peerAddress.isNull() || !peerPort) {
        emit warningMessage(tr("Failed to extract peer info (address, port)"));
        return;
    }

    const auto client = std::find_if(knownClients.begin(), knownClients.end(),
                                     [&](const std::unique_ptr<QDtls> &connection){
        return connection->peerAddress() == peerAddress
               && connection->peerPort() == peerPort;
    });
    //! [4]

    //! [5]
    if (client == knownClients.end())
        return handleNewConnection(peerAddress, peerPort, dgram);
    //! [5]

    //! [6]
    if ((*client)->isConnectionEncrypted()) {
        decryptDatagram(client->get(), dgram);
        if ((*client)->dtlsError() == QDtlsError::RemoteClosedConnectionError)
            knownClients.erase(client);
        return;
    }
    //! [6]

    //! [7]
    doHandshake(client->get(), dgram);
    //! [7]
}

//! [13]
void DtlsServer::pskRequired(QSslPreSharedKeyAuthenticator *auth)
{
    Q_ASSERT(auth);

    emit infoMessage(tr("PSK callback, received a client's identity: '%1'")
                     .arg(QString::fromLatin1(auth->identity())));
    auth->setPreSharedKey(QByteArrayLiteral("\x1a\x2b\x3c\x4d\x5e\x6f"));
}
//! [13]

//! [8]
void DtlsServer::handleNewConnection(const QHostAddress &peerAddress,
                                     quint16 peerPort, const QByteArray &clientHello)
{
    if (!listening)
        return;

    const QString peerInfo = peer_info(peerAddress, peerPort);
    if (cookieSender.verifyClient(&serverSocket, clientHello, peerAddress, peerPort)) {
        emit infoMessage(peerInfo + tr(": verified, starting a handshake"));
    //! [8]
    //! [9]
        std::unique_ptr<QDtls> newConnection{new QDtls{QSslSocket::SslServerMode}};
        newConnection->setDtlsConfiguration(serverConfiguration);
        newConnection->setPeer(peerAddress, peerPort);
        newConnection->connect(newConnection.get(), &QDtls::pskRequired,
                               this, &DtlsServer::pskRequired);
        knownClients.push_back(std::move(newConnection));
        doHandshake(knownClients.back().get(), clientHello);
    //! [9]
    } else if (cookieSender.dtlsError() != QDtlsError::NoError) {
        emit errorMessage(tr("DTLS error: ") + cookieSender.dtlsErrorString());
    } else {
        emit infoMessage(peerInfo + tr(": not verified yet"));
    }
}

//! [11]
void DtlsServer::doHandshake(QDtls *newConnection, const QByteArray &clientHello)
{
    const bool result = newConnection->doHandshake(&serverSocket, clientHello);
    if (!result) {
        emit errorMessage(newConnection->dtlsErrorString());
        return;
    }

    const QString peerInfo = peer_info(newConnection->peerAddress(),
                                       newConnection->peerPort());
    switch (newConnection->handshakeState()) {
    case QDtls::HandshakeInProgress:
        emit infoMessage(peerInfo + tr(": handshake is in progress ..."));
        break;
    case QDtls::HandshakeComplete:
        emit infoMessage(tr("Connection with %1 encrypted. %2")
                         .arg(peerInfo, connection_info(newConnection)));
        break;
    default:
        Q_UNREACHABLE();
    }
}
//! [11]