1 /*
2  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef RTC_BASE_SSL_ADAPTER_H_
12 #define RTC_BASE_SSL_ADAPTER_H_
13 
14 #include <string>
15 #include <vector>
16 
17 #include "rtc_base/async_socket.h"
18 #include "rtc_base/ssl_certificate.h"
19 #include "rtc_base/ssl_identity.h"
20 #include "rtc_base/ssl_stream_adapter.h"
21 #include "rtc_base/system/rtc_export.h"
22 
23 namespace rtc {
24 
25 class SSLAdapter;
26 
27 // Class for creating SSL adapters with shared state, e.g., a session cache,
28 // which allows clients to resume SSL sessions to previously-contacted hosts.
29 // Clients should create the factory using Create(), set up the factory as
30 // needed using SetMode, and then call CreateAdapter to create adapters when
31 // needed.
32 class SSLAdapterFactory {
33  public:
~SSLAdapterFactory()34   virtual ~SSLAdapterFactory() {}
35 
36   // Specifies whether TLS or DTLS is to be used for the SSL adapters.
37   virtual void SetMode(SSLMode mode) = 0;
38 
39   // Specify a custom certificate verifier for SSL.
40   virtual void SetCertVerifier(SSLCertificateVerifier* ssl_cert_verifier) = 0;
41 
42   // Creates a new SSL adapter, but from a shared context.
43   virtual SSLAdapter* CreateAdapter(AsyncSocket* socket) = 0;
44 
45   static SSLAdapterFactory* Create();
46 };
47 
48 // Class that abstracts a client-to-server SSL session. It can be created
49 // standalone, via SSLAdapter::Create, or through a factory as described above,
50 // in which case it will share state with other SSLAdapters created from the
51 // same factory.
52 // After creation, call StartSSL to initiate the SSL handshake to the server.
53 class SSLAdapter : public AsyncSocketAdapter {
54  public:
SSLAdapter(AsyncSocket * socket)55   explicit SSLAdapter(AsyncSocket* socket) : AsyncSocketAdapter(socket) {}
56 
57   // Methods that control server certificate verification, used in unit tests.
58   // Do not call these methods in production code.
59   // TODO(juberti): Remove the opportunistic encryption mechanism in
60   // BasicPacketSocketFactory that uses this function.
61   virtual void SetIgnoreBadCert(bool ignore) = 0;
62 
63   virtual void SetAlpnProtocols(const std::vector<std::string>& protos) = 0;
64   virtual void SetEllipticCurves(const std::vector<std::string>& curves) = 0;
65 
66   // Do DTLS or TLS (default is TLS, if unspecified)
67   virtual void SetMode(SSLMode mode) = 0;
68   // Specify a custom certificate verifier for SSL.
69   virtual void SetCertVerifier(SSLCertificateVerifier* ssl_cert_verifier) = 0;
70 
71   // Set the certificate this socket will present to incoming clients.
72   // Takes ownership of |identity|.
73   virtual void SetIdentity(std::unique_ptr<SSLIdentity> identity) = 0;
74 
75   // Choose whether the socket acts as a server socket or client socket.
76   virtual void SetRole(SSLRole role) = 0;
77 
78   // StartSSL returns 0 if successful.
79   // If StartSSL is called while the socket is closed or connecting, the SSL
80   // negotiation will begin as soon as the socket connects.
81   virtual int StartSSL(const char* hostname) = 0;
82 
83   // When an SSLAdapterFactory is used, an SSLAdapter may be used to resume
84   // a previous SSL session, which results in an abbreviated handshake.
85   // This method, if called after SSL has been established for this adapter,
86   // indicates whether the current session is a resumption of a previous
87   // session.
88   virtual bool IsResumedSession() = 0;
89 
90   // Create the default SSL adapter for this platform. On failure, returns null
91   // and deletes |socket|. Otherwise, the returned SSLAdapter takes ownership
92   // of |socket|.
93   static SSLAdapter* Create(AsyncSocket* socket);
94 };
95 
96 ///////////////////////////////////////////////////////////////////////////////
97 
98 // Call this on the main thread, before using SSL.
99 // Call CleanupSSL when finished with SSL.
100 RTC_EXPORT bool InitializeSSL();
101 
102 // Call to cleanup additional threads, and also the main thread.
103 RTC_EXPORT bool CleanupSSL();
104 
105 }  // namespace rtc
106 
107 #endif  // RTC_BASE_SSL_ADAPTER_H_
108