added booted?/boot methods
[strongswan.git] / src / dumm / mconsole.c
1 /*
2 * Copyright (C) 2007 Martin Willi
3 * Hochschule fuer Technik Rapperswil
4 * Copyright (C) 2001-2004 Jeff Dike
5 *
6 * Based on the "uml_mconsole" utility from Jeff Dike.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 * for more details.
17 */
18
19 #define _GNU_SOURCE
20
21 #include <sys/types.h>
22 #include <unistd.h>
23 #include <stdio.h>
24 #include <sys/socket.h>
25 #include <errno.h>
26 #include <sys/un.h>
27
28 #include <debug.h>
29
30 #include "mconsole.h"
31
32 #define MCONSOLE_MAGIC 0xcafebabe
33 #define MCONSOLE_VERSION 2
34 #define MCONSOLE_MAX_DATA 512
35
36 typedef struct private_mconsole_t private_mconsole_t;
37
38 struct private_mconsole_t {
39 /** public interface */
40 mconsole_t public;
41 /** mconsole socket */
42 int console;
43 /** notify socket */
44 int notify;
45 /** address of uml socket */
46 struct sockaddr_un uml;
47 /** idle function */
48 void (*idle)(void);
49 };
50
51 /**
52 * mconsole message format from "arch/um/include/mconsole.h"
53 */
54 typedef struct mconsole_request mconsole_request;
55 /** mconsole request message */
56 struct mconsole_request {
57 u_int32_t magic;
58 u_int32_t version;
59 u_int32_t len;
60 char data[MCONSOLE_MAX_DATA];
61 };
62
63
64 typedef struct mconsole_reply mconsole_reply;
65 /** mconsole reply message */
66 struct mconsole_reply {
67 u_int32_t err;
68 u_int32_t more;
69 u_int32_t len;
70 char data[MCONSOLE_MAX_DATA];
71 };
72
73 typedef struct mconsole_notify mconsole_notify;
74 /** mconsole notify message */
75 struct mconsole_notify {
76 u_int32_t magic;
77 u_int32_t version;
78 enum {
79 MCONSOLE_SOCKET,
80 MCONSOLE_PANIC,
81 MCONSOLE_HANG,
82 MCONSOLE_USER_NOTIFY,
83 } type;
84 u_int32_t len;
85 char data[MCONSOLE_MAX_DATA];
86 };
87
88 /**
89 * send a request to UML using mconsole
90 */
91 static int request(private_mconsole_t *this, void(*cb)(void*,char*,size_t),
92 void *data, char *command, ...)
93 {
94 mconsole_request request;
95 mconsole_reply reply;
96 int len, flags = 0;
97 va_list args;
98
99 memset(&request, 0, sizeof(request));
100 request.magic = MCONSOLE_MAGIC;
101 request.version = MCONSOLE_VERSION;
102 va_start(args, command);
103 request.len = vsnprintf(request.data, sizeof(request.data), command, args);
104 va_end(args);
105
106 if (this->idle)
107 {
108 flags = MSG_DONTWAIT;
109 }
110 do
111 {
112 if (this->idle)
113 {
114 this->idle();
115 }
116 len = sendto(this->console, &request, sizeof(request), flags,
117 (struct sockaddr*)&this->uml, sizeof(this->uml));
118 }
119 while (len < 0 && (errno == EINTR || errno == EAGAIN));
120
121 if (len < 0)
122 {
123 DBG1("sending mconsole command to UML failed: %m");
124 return -1;
125 }
126 do
127 {
128 len = recv(this->console, &reply, sizeof(reply), flags);
129 if (len < 0 && (errno == EINTR || errno == EAGAIN))
130 {
131 if (this->idle)
132 {
133 this->idle();
134 }
135 continue;
136 }
137 if (len < 0)
138 {
139 DBG1("receiving from mconsole failed: %m");
140 return -1;
141 }
142 if (len > 0)
143 {
144 if (cb)
145 {
146 cb(data, reply.data, reply.len);
147 }
148 else if (reply.err)
149 {
150 if (reply.len && *reply.data)
151 {
152 DBG1("received mconsole error %d: %*.s",
153 reply.err, reply.len, reply.data);
154 }
155 break;
156 }
157 }
158 }
159 while (reply.more);
160
161 return reply.err;
162 }
163
164 /**
165 * ignore error message
166 */
167 static void ignore(void *data, char *buf, size_t len)
168 {
169 }
170
171 /**
172 * Implementation of mconsole_t.add_iface.
173 */
174 static bool add_iface(private_mconsole_t *this, char *guest, char *host)
175 {
176 int tries = 0;
177
178 while (tries++ < 5)
179 {
180 if (request(this, ignore, NULL, "config %s=tuntap,%s", guest, host) == 0)
181 {
182 return TRUE;
183 }
184 usleep(10000 * tries * tries);
185 }
186 return FALSE;
187 }
188
189 /**
190 * Implementation of mconsole_t.del_iface.
191 */
192 static bool del_iface(private_mconsole_t *this, char *guest)
193 {
194 if (request(this, NULL, NULL, "remove %s", guest) != 0)
195 {
196 return FALSE;
197 }
198 return TRUE;
199 }
200
201 /**
202 * Implementation of mconsole_t.exec
203 */
204 static int exec(private_mconsole_t *this, void(*cb)(void*,char*,size_t),
205 void *data, char *cmd)
206 {
207 return request(this, cb, data, "%s", cmd);
208 }
209
210 /**
211 * Poll until guest is ready
212 */
213 static void wait_bootup(private_mconsole_t *this)
214 {
215 /* wait for init process to appear */
216 while (request(this, ignore, NULL, "exec ps -p 1 > /dev/null"))
217 {
218 if (this->idle)
219 {
220 this->idle();
221 }
222 usleep(100000);
223 }
224 }
225
226 /**
227 * Implementation of mconsole_t.destroy.
228 */
229 static void destroy(private_mconsole_t *this)
230 {
231 close(this->console);
232 close(this->notify);
233 free(this);
234 }
235
236 /**
237 * setup the mconsole notify connection and wait for its readiness
238 */
239 static bool wait_for_notify(private_mconsole_t *this, char *nsock)
240 {
241 struct sockaddr_un addr;
242 mconsole_notify notify;
243 int len, flags = 0;
244
245 this->notify = socket(AF_UNIX, SOCK_DGRAM, 0);
246 if (this->notify < 0)
247 {
248 DBG1("opening mconsole notify socket failed: %m");
249 return FALSE;
250 }
251 memset(&addr, 0, sizeof(addr));
252 addr.sun_family = AF_UNIX;
253 strncpy(addr.sun_path, nsock, sizeof(addr.sun_path));
254 if (bind(this->notify, (struct sockaddr*)&addr, sizeof(addr)) < 0)
255 {
256 DBG1("binding mconsole notify socket to '%s' failed: %m", nsock);
257 close(this->notify);
258 return FALSE;
259 }
260 if (this->idle)
261 {
262 flags = MSG_DONTWAIT;
263 }
264 do
265 {
266 if (this->idle)
267 {
268 this->idle();
269 }
270 len = recvfrom(this->notify, &notify, sizeof(notify), flags, NULL, 0);
271 }
272 while (len < 0 && (errno == EINTR || errno == EAGAIN));
273
274 if (len < 0 || len >= sizeof(notify))
275 {
276 DBG1("reading from mconsole notify socket failed: %m");
277 close(this->notify);
278 unlink(nsock);
279 return FALSE;
280 }
281 if (notify.magic != MCONSOLE_MAGIC ||
282 notify.version != MCONSOLE_VERSION ||
283 notify.type != MCONSOLE_SOCKET)
284 {
285 DBG1("received unexpected message from mconsole notify socket: %b",
286 &notify, sizeof(notify));
287 close(this->notify);
288 unlink(nsock);
289 return FALSE;
290 }
291 memset(&this->uml, 0, sizeof(this->uml));
292 this->uml.sun_family = AF_UNIX;
293 strncpy(this->uml.sun_path, (char*)&notify.data, sizeof(this->uml.sun_path));
294 return TRUE;
295 }
296
297 /**
298 * setup the mconsole console connection
299 */
300 static bool setup_console(private_mconsole_t *this)
301 {
302 struct sockaddr_un addr;
303
304 this->console = socket(AF_UNIX, SOCK_DGRAM, 0);
305 if (this->console < 0)
306 {
307 DBG1("opening mconsole socket failed: %m");
308 return FALSE;
309 }
310 memset(&addr, 0, sizeof(addr));
311 addr.sun_family = AF_UNIX;
312 snprintf(&addr.sun_path[1], sizeof(addr.sun_path)-1, "%5d-%d",
313 getpid(), this->console);
314 if (bind(this->console, (struct sockaddr*)&addr, sizeof(addr)) < 0)
315 {
316 DBG1("binding mconsole socket to '%s' failed: %m", &addr.sun_path[1]);
317 close(this->console);
318 return FALSE;
319 }
320 return TRUE;
321 }
322
323 /**
324 * create the mconsole instance
325 */
326 mconsole_t *mconsole_create(char *notify, void(*idle)(void))
327 {
328 private_mconsole_t *this = malloc_thing(private_mconsole_t);
329
330 this->public.add_iface = (bool(*)(mconsole_t*, char *guest, char *host))add_iface;
331 this->public.del_iface = (bool(*)(mconsole_t*, char *guest))del_iface;
332 this->public.exec = (int(*)(mconsole_t*, void(*cb)(void*,char*,size_t), void *data, char *cmd))exec;
333 this->public.destroy = (void*)destroy;
334
335 this->idle = idle;
336
337 if (!wait_for_notify(this, notify))
338 {
339 free(this);
340 return NULL;
341 }
342
343 if (!setup_console(this))
344 {
345 close(this->notify);
346 unlink(notify);
347 free(this);
348 return NULL;
349 }
350 unlink(notify);
351
352 wait_bootup(this);
353
354 return &this->public;
355 }
356