xref: /netbsd-src/external/apache2/mDNSResponder/dist/mDNSPosix/mDNSPosix.h (revision 7acf6d0e5e0389907a20f8f0de48a871e49c29e8)
1 /* -*- Mode: C; tab-width: 4; c-file-style: "bsd"; c-basic-offset: 4; fill-column: 108; indent-tabs-mode: nil; -*-
2  *
3  * Copyright (c) 2002-2021 Apple Computer, Inc. All rights reserved.
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *     https://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 #ifndef __mDNSPlatformPosix_h
19 #define __mDNSPlatformPosix_h
20 
21 #include <signal.h>
22 #include <sys/time.h>
23 
24 #ifdef  __cplusplus
25 extern "C" {
26 #endif
27 
28 // PosixNetworkInterface is a record extension of the core NetworkInterfaceInfo
29 // type that supports extra fields needed by the Posix platform.
30 //
31 // IMPORTANT: coreIntf must be the first field in the structure because
32 // we cast between pointers to the two different types regularly.
33 
34 typedef struct PosixNetworkInterface PosixNetworkInterface;
35 
36 struct PosixNetworkInterface
37 {
38     NetworkInterfaceInfo coreIntf;      // MUST be the first element in this structure
39     mDNSs32 LastSeen;
40     char *                  intfName;
41     PosixNetworkInterface * aliasIntf;
42     int index;
43     int multicastSocket4;
44 #if HAVE_IPV6
45     int multicastSocket6;
46 #endif
47 };
48 
49 // This is a global because debugf_() needs to be able to check its value
50 extern int gMDNSPlatformPosixVerboseLevel;
51 
52 struct mDNS_PlatformSupport_struct
53 {
54     int unicastSocket4;
55 #if HAVE_IPV6
56     int unicastSocket6;
57 #endif
58 };
59 
60 // We keep a list of client-supplied event sources in PosixEventSource records
61 // Add a file descriptor to the set that mDNSPosixRunEventLoopOnce() listens to.
62 #define PosixEventFlag_OnList   1
63 #define PosixEventFlag_Read     2
64 #define PosixEventFlag_Write    4
65 
66 typedef void (*mDNSPosixEventCallback)(int fd, void *context);
67 struct PosixEventSource
68 {
69     struct PosixEventSource *next;
70     mDNSPosixEventCallback readCallback;
71     mDNSPosixEventCallback writeCallback;
72     const char *readTaskName;
73     const char *writeTaskName;
74     void *readContext;
75     void *writeContext;
76     int fd;
77     unsigned flags;
78 };
79 typedef struct PosixEventSource PosixEventSource;
80 
81 struct UDPSocket_struct
82 {
83     mDNSIPPort port;
84     PosixEventSource events;
85     mDNSAddr remoteAddress;
86     mDNSIPPort remotePort;
87     mDNSBool setup;
88     mDNSBool randomizePort;
89 };
90 
91 struct TCPSocket_struct
92 {
93     mDNSIPPort port;            // MUST BE FIRST FIELD -- mDNSCore expects every TCPSocket_struct to begin with mDNSIPPort
94     TCPSocketFlags flags;       // MUST BE SECOND FIELD -- mDNSCore expects every TCPSocket_struct have TCPSocketFlags flags after mDNSIPPort
95     TCPConnectionCallback callback;
96     PosixEventSource events;
97     TLSContext *tls;
98     domainname *hostname;
99     mDNSAddr remoteAddress;
100     mDNSIPPort remotePort;
101     void *context;
102     mDNSBool setup;
103     mDNSBool connected;
104     mStatus err;
105 };
106 
107 struct TCPListener_struct
108 {
109     TCPAcceptedCallback callback;
110     PosixEventSource events;
111     TLSServerContext *tls;
112     void *context;
113     mDNSAddr_Type addressType;
114     TCPSocketFlags socketFlags;
115 };
116 
117 #define uDNS_SERVERS_FILE "/etc/resolv.conf"
118 extern int ParseDNSServers(mDNS *m, const char *filePath);
119 extern mStatus mDNSPlatformPosixRefreshInterfaceList(mDNS *const m);
120 // See comment in implementation.
121 
122 // Call mDNSPosixGetFDSet before calling select(), to update the parameters
123 // as may be necessary to meet the needs of the mDNSCore code.
124 // The timeout pointer MUST NOT be NULL.
125 // Set timeout->tv_sec to FutureTime if you want to have effectively no timeout
126 // After calling mDNSPosixGetFDSet(), call select(nfds, &readfds, NULL, NULL, &timeout); as usual
127 // After select() returns, call mDNSPosixProcessFDSet() to let mDNSCore do its work
128 extern void mDNSPosixGetFDSet(mDNS *m, int *nfds, fd_set *readfds, fd_set *writefds, struct timeval *timeout);
129 extern void mDNSPosixProcessFDSet(mDNS *const m, fd_set *readfds, fd_set *writefds);
130 
131 extern mStatus mDNSPosixAddFDToEventLoop( int fd, mDNSPosixEventCallback callback, void *context);
132 extern mStatus mDNSPosixRemoveFDFromEventLoop( int fd);
133 extern mStatus mDNSPosixListenForSignalInEventLoop( int signum);
134 extern mStatus mDNSPosixIgnoreSignalInEventLoop( int signum);
135 extern mStatus mDNSPosixRunEventLoopOnce( mDNS *m, const struct timeval *pTimeout, sigset_t *pSignalsReceived, mDNSBool *pDataDispatched);
136 
137 extern mStatus mDNSPosixListenForSignalInEventLoop( int signum);
138 extern mStatus mDNSPosixIgnoreSignalInEventLoop( int signum);
139 extern mStatus mDNSPosixRunEventLoopOnce( mDNS *m, const struct timeval *pTimeout, sigset_t *pSignalsReceived, mDNSBool *pDataDispatched);
140 
141 // From the TLS shim:
142 extern mDNSBool mDNSPosixTLSInit(void);
143 extern void mDNSPosixTLSContextFree(TLSContext *tls);
144 extern TLSContext *mDNSPosixTLSClientStateCreate(TCPSocket *sock);
145 extern mDNSBool mDNSPosixTLSStart(TCPSocket *sock);
146 extern TLSContext *PosixTLSAccept(TCPListener *listenContext);
147 extern int mDNSPosixTLSRead(TCPSocket *sock, void *buf, unsigned long buflen, mDNSBool *closed);
148 extern int mDNSPosixTLSWrite(TCPSocket *sock, const void *buf, unsigned long buflen);
149 
150 #ifdef  __cplusplus
151 }
152 #endif
153 
154 #endif
155