QCA

publickeyexample.cpp
1 /*
2  Copyright (C) 2003 Justin Karneges <[email protected]>
3  Copyright (C) 2005 Brad Hards <[email protected]>
4 
5  Permission is hereby granted, free of charge, to any person obtaining a copy
6  of this software and associated documentation files (the "Software"), to deal
7  in the Software without restriction, including without limitation the rights
8  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9  copies of the Software, and to permit persons to whom the Software is
10  furnished to do so, subject to the following conditions:
11 
12  The above copyright notice and this permission notice shall be included in
13  all copies or substantial portions of the Software.
14 
15  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18  AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
19  AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
20  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
21 */
22 
23 #include <QtCrypto>
24 
25 #include <QCoreApplication>
26 
27 #include <iostream>
28 
29 #ifdef QT_STATICPLUGIN
30 #include "import_plugins.h"
31 #endif
32 
33 int main(int argc, char **argv)
34 {
35  // the Initializer object sets things up, and
36  // also does cleanup when it goes out of scope
38 
39  QCoreApplication app(argc, argv);
40 
41  // We need to ensure that we have certificate handling support
42  if (!QCA::isSupported("cert")) {
43  std::cout << "Sorry, no PKI certificate support" << std::endl;
44  return 1;
45  }
46 
47  // Read in a private key
48  QCA::PrivateKey privKey;
49  QCA::ConvertResult convRes;
50  QCA::SecureArray passPhrase = "start";
51  privKey = QCA::PrivateKey::fromPEMFile(QStringLiteral("Userkey.pem"), passPhrase, &convRes);
52  if (convRes != QCA::ConvertGood) {
53  std::cout << "Sorry, could not import Private Key" << std::endl;
54  return 1;
55  }
56 
57  // Read in a matching public key cert
58  // you could also build this using the fromPEMFile() method
59  QCA::Certificate pubCert(QStringLiteral("User.pem"));
60  if (pubCert.isNull()) {
61  std::cout << "Sorry, could not import public key certificate" << std::endl;
62  return 1;
63  }
64  // We are building the certificate into a SecureMessageKey object, via a
65  // CertificateChain
66  QCA::SecureMessageKey secMsgKey;
68  chain += pubCert;
69  secMsgKey.setX509CertificateChain(chain);
70 
71  // build up a SecureMessage object, based on our public key certificate
72  QCA::CMS cms;
73  QCA::SecureMessage msg(&cms);
74  msg.setRecipient(secMsgKey);
75 
76  // Some plain text - we use the first command line argument if provided
77  QByteArray plainText = (argc >= 2) ? argv[1] : "What do ya want for nuthin'";
78 
79  // Now use the SecureMessage object to encrypt the plain text.
80  msg.startEncrypt();
81  msg.update(plainText);
82  msg.end();
83  // I think it is reasonable to wait for 1 second for this
84  msg.waitForFinished(1000);
85 
86  // check to see if it worked
87  if (!msg.success()) {
88  std::cout << "Error encrypting: " << msg.errorCode() << std::endl;
89  return 1;
90  }
91 
92  // get the result
93  QCA::SecureArray cipherText = msg.read();
94  QCA::Base64 enc;
95  std::cout << plainText.data() << " encrypts to (in base 64): ";
96  std::cout << qPrintable(enc.arrayToString(cipherText)) << std::endl;
97 
98  // Show we can decrypt it with the private key
99  if (!privKey.canDecrypt()) {
100  std::cout << "Private key cannot be used to decrypt" << std::endl;
101  return 1;
102  }
103  QCA::SecureArray plainTextResult;
104  if (0 == privKey.decrypt(cipherText, &plainTextResult, QCA::EME_PKCS1_OAEP)) {
105  std::cout << "Decryption process failed" << std::endl;
106  return 1;
107  }
108 
109  std::cout << qPrintable(enc.arrayToString(cipherText));
110  std::cout << " (in base 64) decrypts to: ";
111  std::cout << plainTextResult.data() << std::endl;
112 
113  return 0;
114 }
ConvertResult
Return value from a format conversion.
Key for SecureMessage system.
Generic private key.
QString arrayToString(const MemoryRegion &a)
Process an array in the "forward" direction, returning a QString.
Base64 encoding / decoding
void setX509CertificateChain(const CertificateChain &c)
Set the public key part of this X.509 key.
Conversion succeeded, results should be valid.
bool canDecrypt() const
Test if this key can be used for decryption.
char * data()
Pointer to the data in the secure array.
QCA_EXPORT bool isSupported(const char *features, const QString &provider=QString())
Test if a capability (algorithm) is available.
Optimal asymmetric encryption padding (PKCS#1, Version 2.0)
Definition: qca_publickey.h:57
bool decrypt(const SecureArray &in, SecureArray *out, EncryptionAlgorithm alg)
Decrypt the message.
QCA_EXPORT void init()
Initialise QCA.
Secure array of bytes.
Definition: qca_tools.h:316
A chain of related Certificates.
Definition: qca_cert.h:1225
char * data()
Convenience method for initialising and cleaning up QCA.
Definition: qca_core.h:659
Public Key (X.509) certificate.
Definition: qca_cert.h:856
static PrivateKey fromPEMFile(const QString &fileName, const SecureArray &passphrase=SecureArray(), ConvertResult *result=nullptr, const QString &provider=QString())
Import the key in Privacy Enhanced Mail (PEM) format from a file.
Class representing a secure message.
QByteArray::iterator end()
Cryptographic Message Syntax messaging system.
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