xref: /freebsd/contrib/unbound/daemon/remote.h (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
1 /*
2  * daemon/remote.h - remote control for the unbound daemon.
3  *
4  * Copyright (c) 2008, NLnet Labs. All rights reserved.
5  *
6  * This software is open source.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * Redistributions of source code must retain the above copyright notice,
13  * this list of conditions and the following disclaimer.
14  *
15  * Redistributions in binary form must reproduce the above copyright notice,
16  * this list of conditions and the following disclaimer in the documentation
17  * and/or other materials provided with the distribution.
18  *
19  * Neither the name of the NLNET LABS nor the names of its contributors may
20  * be used to endorse or promote products derived from this software without
21  * specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /**
37  * \file
38  *
39  * This file contains the remote control functionality for the daemon.
40  * The remote control can be performed using either the commandline
41  * unbound-control tool, or a SSLv3/TLS capable web browser.
42  * The channel is secured using SSLv3 or TLSv1, and certificates.
43  * Both the server and the client(control tool) have their own keys.
44  */
45 
46 #ifndef DAEMON_REMOTE_H
47 #define DAEMON_REMOTE_H
48 #ifdef HAVE_OPENSSL_SSL_H
49 #include "openssl/ssl.h"
50 #endif
51 struct config_file;
52 struct listen_list;
53 struct listen_port;
54 struct worker;
55 struct comm_reply;
56 struct comm_point;
57 struct daemon_remote;
58 
59 /** number of milliseconds timeout on incoming remote control handshake */
60 #define REMOTE_CONTROL_TCP_TIMEOUT 120000
61 
62 /**
63  * a busy control command connection, SSL state
64  */
65 struct rc_state {
66 	/** the next item in list */
67 	struct rc_state* next;
68 	/** the commpoint */
69 	struct comm_point* c;
70 	/** in the handshake part */
71 	enum { rc_none, rc_hs_read, rc_hs_write } shake_state;
72 #ifdef HAVE_SSL
73 	/** the ssl state */
74 	SSL* ssl;
75 #endif
76 	/** file descriptor */
77         int fd;
78 	/** the rc this is part of */
79 	struct daemon_remote* rc;
80 };
81 
82 /**
83  * The remote control tool state.
84  * The state is only created for the first thread, other threads
85  * are called from this thread.  Only the first threads listens to
86  * the control port.  The other threads do not, but are called on the
87  * command channel(pipe) from the first thread.
88  */
89 struct daemon_remote {
90 	/** the worker for this remote control */
91 	struct worker* worker;
92 	/** commpoints for accepting remote control connections */
93 	struct listen_list* accept_list;
94 	/* if certificates are used */
95 	int use_cert;
96 	/** number of active commpoints that are handling remote control */
97 	int active;
98 	/** max active commpoints */
99 	int max_active;
100 	/** current commpoints busy; should be a short list, malloced */
101 	struct rc_state* busy_list;
102 #ifdef HAVE_SSL
103 	/** the SSL context for creating new SSL streams */
104 	SSL_CTX* ctx;
105 #endif
106 };
107 
108 /**
109  * Connection to print to, either SSL or plain over fd
110  */
111 struct remote_stream {
112 #ifdef HAVE_SSL
113 	/** SSL structure, nonNULL if using SSL */
114 	SSL* ssl;
115 #endif
116 	/** file descriptor for plain transfer */
117 	int fd;
118 };
119 typedef struct remote_stream RES;
120 
121 /**
122  * Create new remote control state for the daemon.
123  * @param cfg: config file with key file settings.
124  * @return new state, or NULL on failure.
125  */
126 struct daemon_remote* daemon_remote_create(struct config_file* cfg);
127 
128 /**
129  * remote control state to delete.
130  * @param rc: state to delete.
131  */
132 void daemon_remote_delete(struct daemon_remote* rc);
133 
134 /**
135  * remote control state to clear up. Busy and accept points are closed.
136  * Does not delete the rc itself, or the ssl context (with its keys).
137  * @param rc: state to clear.
138  */
139 void daemon_remote_clear(struct daemon_remote* rc);
140 
141 /**
142  * Open and create listening ports for remote control.
143  * @param cfg: config options.
144  * @return list of ports or NULL on failure.
145  *	can be freed with listening_ports_free().
146  */
147 struct listen_port* daemon_remote_open_ports(struct config_file* cfg);
148 
149 /**
150  * Setup comm points for accepting remote control connections.
151  * @param rc: state
152  * @param ports: already opened ports.
153  * @param worker: worker with communication base. and links to command channels.
154  * @return false on error.
155  */
156 int daemon_remote_open_accept(struct daemon_remote* rc,
157 	struct listen_port* ports, struct worker* worker);
158 
159 /**
160  * Stop accept handlers for TCP (until enabled again)
161  * @param rc: state
162  */
163 void daemon_remote_stop_accept(struct daemon_remote* rc);
164 
165 /**
166  * Stop accept handlers for TCP (until enabled again)
167  * @param rc: state
168  */
169 void daemon_remote_start_accept(struct daemon_remote* rc);
170 
171 /**
172  * Handle nonthreaded remote cmd execution.
173  * @param worker: this worker (the remote worker).
174  */
175 void daemon_remote_exec(struct worker* worker);
176 
177 #ifdef HAVE_SSL
178 /**
179  * Print fixed line of text over ssl connection in blocking mode
180  * @param ssl: print to
181  * @param text: the text.
182  * @return false on connection failure.
183  */
184 int ssl_print_text(RES* ssl, const char* text);
185 
186 /**
187  * printf style printing to the ssl connection
188  * @param ssl: the RES connection to print to. Blocking.
189  * @param format: printf style format string.
190  * @return success or false on a network failure.
191  */
192 int ssl_printf(RES* ssl, const char* format, ...)
193         ATTR_FORMAT(printf, 2, 3);
194 
195 /**
196  * Read until \n is encountered
197  * If stream signals EOF, the string up to then is returned (without \n).
198  * @param ssl: the RES connection to read from. blocking.
199  * @param buf: buffer to read to.
200  * @param max: size of buffer.
201  * @return false on connection failure.
202  */
203 int ssl_read_line(RES* ssl, char* buf, size_t max);
204 #endif /* HAVE_SSL */
205 
206 #endif /* DAEMON_REMOTE_H */
207