xref: /aosp_15_r20/external/webrtc/api/dtls_transport_interface.h (revision d9f758449e529ab9291ac668be2861e7a55c2422)
1 /*
2  *  Copyright 2018 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 API_DTLS_TRANSPORT_INTERFACE_H_
12 #define API_DTLS_TRANSPORT_INTERFACE_H_
13 
14 #include <memory>
15 #include <utility>
16 
17 #include "absl/types/optional.h"
18 #include "api/ice_transport_interface.h"
19 #include "api/rtc_error.h"
20 #include "api/scoped_refptr.h"
21 #include "rtc_base/ref_count.h"
22 #include "rtc_base/ssl_certificate.h"
23 #include "rtc_base/system/rtc_export.h"
24 
25 namespace webrtc {
26 
27 // States of a DTLS transport, corresponding to the JS API specification.
28 // http://w3c.github.io/webrtc-pc/#dom-rtcdtlstransportstate
29 enum class DtlsTransportState {
30   kNew,         // Has not started negotiating yet.
31   kConnecting,  // In the process of negotiating a secure connection.
32   kConnected,   // Completed negotiation and verified fingerprints.
33   kClosed,      // Intentionally closed.
34   kFailed,      // Failure due to an error or failing to verify a remote
35                 // fingerprint.
36   kNumValues
37 };
38 
39 enum class DtlsTransportTlsRole {
40   kServer,  // Other end sends CLIENT_HELLO
41   kClient   // This end sends CLIENT_HELLO
42 };
43 
44 // This object gives snapshot information about the changeable state of a
45 // DTLSTransport.
46 class RTC_EXPORT DtlsTransportInformation {
47  public:
48   DtlsTransportInformation();
49   explicit DtlsTransportInformation(DtlsTransportState state);
50   DtlsTransportInformation(
51       DtlsTransportState state,
52       absl::optional<DtlsTransportTlsRole> role,
53       absl::optional<int> tls_version,
54       absl::optional<int> ssl_cipher_suite,
55       absl::optional<int> srtp_cipher_suite,
56       std::unique_ptr<rtc::SSLCertChain> remote_ssl_certificates);
57   ABSL_DEPRECATED("Use version with role parameter")
58   DtlsTransportInformation(
59       DtlsTransportState state,
60       absl::optional<int> tls_version,
61       absl::optional<int> ssl_cipher_suite,
62       absl::optional<int> srtp_cipher_suite,
63       std::unique_ptr<rtc::SSLCertChain> remote_ssl_certificates);
64 
65   // Copy and assign
66   DtlsTransportInformation(const DtlsTransportInformation& c);
67   DtlsTransportInformation& operator=(const DtlsTransportInformation& c);
68   // Move
69   DtlsTransportInformation(DtlsTransportInformation&& other) = default;
70   DtlsTransportInformation& operator=(DtlsTransportInformation&& other) =
71       default;
72 
state()73   DtlsTransportState state() const { return state_; }
role()74   absl::optional<DtlsTransportTlsRole> role() const { return role_; }
tls_version()75   absl::optional<int> tls_version() const { return tls_version_; }
ssl_cipher_suite()76   absl::optional<int> ssl_cipher_suite() const { return ssl_cipher_suite_; }
srtp_cipher_suite()77   absl::optional<int> srtp_cipher_suite() const { return srtp_cipher_suite_; }
78   // The accessor returns a temporary pointer, it does not release ownership.
remote_ssl_certificates()79   const rtc::SSLCertChain* remote_ssl_certificates() const {
80     return remote_ssl_certificates_.get();
81   }
82 
83  private:
84   DtlsTransportState state_;
85   absl::optional<DtlsTransportTlsRole> role_;
86   absl::optional<int> tls_version_;
87   absl::optional<int> ssl_cipher_suite_;
88   absl::optional<int> srtp_cipher_suite_;
89   std::unique_ptr<rtc::SSLCertChain> remote_ssl_certificates_;
90 };
91 
92 class DtlsTransportObserverInterface {
93  public:
94   // This callback carries information about the state of the transport.
95   // The argument is a pass-by-value snapshot of the state.
96   virtual void OnStateChange(DtlsTransportInformation info) = 0;
97   // This callback is called when an error occurs, causing the transport
98   // to go to the kFailed state.
99   virtual void OnError(RTCError error) = 0;
100 
101  protected:
102   virtual ~DtlsTransportObserverInterface() = default;
103 };
104 
105 // A DTLS transport, as represented to the outside world.
106 // This object is created on the network thread, and can only be
107 // accessed on that thread, except for functions explicitly marked otherwise.
108 // References can be held by other threads, and destruction can therefore
109 // be initiated by other threads.
110 class DtlsTransportInterface : public rtc::RefCountInterface {
111  public:
112   // Returns a pointer to the ICE transport that is owned by the DTLS transport.
113   virtual rtc::scoped_refptr<IceTransportInterface> ice_transport() = 0;
114   // Returns information on the state of the DtlsTransport.
115   // This function can be called from other threads.
116   virtual DtlsTransportInformation Information() = 0;
117   // Observer management.
118   virtual void RegisterObserver(DtlsTransportObserverInterface* observer) = 0;
119   virtual void UnregisterObserver() = 0;
120 };
121 
122 }  // namespace webrtc
123 
124 #endif  // API_DTLS_TRANSPORT_INTERFACE_H_
125