1/*
2 * Copyright (c) 2000-2008, 2010-2013 Apple Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23
24/*
25 * Modification History
26 *
27 * June 1, 2001			Allan Nathanson <ajn@apple.com>
28 * - public API conversion
29 *
30 * November 9, 2000		Allan Nathanson <ajn@apple.com>
31 * - initial revision
32 */
33
34#include <TargetConditionals.h>
35#include <SystemConfiguration/SystemConfiguration.h>
36#include <SystemConfiguration/SCPrivate.h>
37#include "SCPreferencesInternal.h"
38#include "SCHelper_client.h"
39
40#include <fcntl.h>
41#include <unistd.h>
42#include <sys/errno.h>
43
44static Boolean
45__SCPreferencesCommitChanges_helper(SCPreferencesRef prefs)
46{
47	CFDataRef		data		= NULL;
48	Boolean			ok;
49	SCPreferencesPrivateRef	prefsPrivate	= (SCPreferencesPrivateRef)prefs;
50	uint32_t		status		= kSCStatusOK;
51	CFDataRef		reply		= NULL;
52
53	if (prefsPrivate->helper_port == MACH_PORT_NULL) {
54		// if no helper
55		status = kSCStatusAccessError;
56		goto fail;
57	}
58
59	if (prefsPrivate->changed) {
60		ok = _SCSerialize(prefsPrivate->prefs, &data, NULL, NULL);
61		if (!ok) {
62			status = kSCStatusFailed;
63			if (_sc_verbose) {
64				SCLog(TRUE, LOG_ERR,
65				      CFSTR("SCPreferencesCommitChanges(-->helper) CFPropertyListCreateData() failed"));
66				SCLog(TRUE, LOG_ERR,
67				      CFSTR("  prefs = %s"),
68				      prefsPrivate->newPath ? prefsPrivate->newPath : prefsPrivate->path);
69			}
70			goto error;
71		}
72	}
73
74	// have the helper "commit" the prefs
75//	status = kSCStatusOK;
76//	reply  = NULL;
77	ok = _SCHelperExec(prefsPrivate->helper_port,
78			   SCHELPER_MSG_PREFS_COMMIT,
79			   data,
80			   &status,
81			   &reply);
82	if (data != NULL) CFRelease(data);
83	if (!ok) {
84		goto fail;
85	}
86
87	if (status != kSCStatusOK) {
88		goto error;
89	}
90
91	if (prefsPrivate->changed) {
92		if (prefsPrivate->signature != NULL) CFRelease(prefsPrivate->signature);
93		prefsPrivate->signature = reply;
94	} else {
95		if (reply != NULL) CFRelease(reply);
96	}
97
98	prefsPrivate->changed = FALSE;
99	return TRUE;
100
101    fail :
102
103	// close helper
104	if (prefsPrivate->helper_port != MACH_PORT_NULL) {
105		_SCHelperClose(&prefsPrivate->helper_port);
106	}
107
108    error :
109
110	// return error
111	if (reply != NULL) CFRelease(reply);
112	_SCErrorSet(status);
113	return FALSE;
114}
115
116
117static ssize_t
118writen(int ref, const void *data, size_t len)
119{
120	size_t		left	= len;
121	ssize_t		n;
122	const void	*p	= data;
123
124	while (left > 0) {
125		if ((n = write(ref, p, left)) == -1) {
126			if (errno != EINTR) {
127				return -1;
128			}
129			n = 0;
130		}
131		left -= n;
132		p += n;
133	}
134	return len;
135}
136
137
138Boolean
139SCPreferencesCommitChanges(SCPreferencesRef prefs)
140{
141	Boolean			ok		= FALSE;
142	char *			path;
143	SCPreferencesPrivateRef	prefsPrivate	= (SCPreferencesPrivateRef)prefs;
144	Boolean			save		= TRUE;
145	struct stat		statBuf;
146	Boolean			wasLocked;
147
148	if (prefs == NULL) {
149		/* sorry, you must provide a session */
150		_SCErrorSet(kSCStatusNoPrefsSession);
151		return FALSE;
152	}
153
154	/*
155	 * Determine if the we have exclusive access to the preferences
156	 * and acquire the lock if necessary.
157	 */
158	wasLocked = prefsPrivate->locked;
159	if (!wasLocked) {
160		if (!SCPreferencesLock(prefs, TRUE)) {
161			SCLog(_sc_verbose, LOG_ERR, CFSTR("SCPreferencesCommitChanges SCPreferencesLock() failed"));
162			return FALSE;
163		}
164	}
165
166	if (prefsPrivate->authorizationData != NULL) {
167		ok = __SCPreferencesCommitChanges_helper(prefs);
168		if (ok) {
169			prefsPrivate->changed = FALSE;
170		}
171		goto done;
172	}
173
174	/*
175	 * if necessary, apply changes
176	 */
177	if (!prefsPrivate->changed) {
178		goto committed;
179	}
180
181	/*
182	 * check if the preferences should be removed
183	 */
184	if (CFDictionaryGetCount(prefsPrivate->prefs) == 0) {
185		CFBooleanRef	val;
186
187		/* if empty */
188		if ((prefsPrivate->options != NULL) &&
189		    CFDictionaryGetValueIfPresent(prefsPrivate->options,
190						  kSCPreferencesOptionRemoveWhenEmpty,
191						  (const void **)&val) &&
192		    isA_CFBoolean(val) &&
193		    CFBooleanGetValue(val)) {
194			/* if we've been asked to remove empty .plists */
195			save = FALSE;
196		}
197	}
198
199	path = prefsPrivate->newPath ? prefsPrivate->newPath : prefsPrivate->path;
200	if (save) {
201		int		fd;
202		CFDataRef	newPrefs;
203		CFIndex		pathLen;
204		char *		thePath;
205
206		if (stat(prefsPrivate->path, &statBuf) == -1) {
207			if (errno == ENOENT) {
208				bzero(&statBuf, sizeof(statBuf));
209				statBuf.st_mode = 0644;
210				statBuf.st_uid  = geteuid();
211				statBuf.st_gid  = getegid();
212			} else {
213				SCLog(_sc_verbose, LOG_ERR, CFSTR("SCPreferencesCommitChanges stat() failed: %s"), strerror(errno));
214				goto done;
215			}
216		}
217
218		/* create the (new) preferences file */
219		pathLen = strlen(path) + sizeof("-new");
220		thePath = CFAllocatorAllocate(NULL, pathLen, 0);
221		snprintf(thePath, pathLen, "%s-new", path);
222
223		fd = open(thePath, O_WRONLY|O_CREAT, statBuf.st_mode);
224		if (fd == -1) {
225			_SCErrorSet(errno);
226			SCLog(_sc_verbose, LOG_ERR, CFSTR("SCPreferencesCommitChanges open() failed: %s"), strerror(errno));
227			CFAllocatorDeallocate(NULL, thePath);
228			goto done;
229		}
230
231		/* preserve permissions */
232		(void) fchown(fd, statBuf.st_uid, statBuf.st_gid);
233		(void) fchmod(fd, statBuf.st_mode);
234
235		/* write the new preferences */
236		newPrefs = CFPropertyListCreateData(NULL,
237						    prefsPrivate->prefs,
238#if	TARGET_OS_IPHONE
239						    kCFPropertyListBinaryFormat_v1_0,
240#else	// TARGET_OS_IPHONE
241						    kCFPropertyListXMLFormat_v1_0,
242#endif	// TARGET_OS_IPHONE
243						    0,
244						    NULL);
245		if (!newPrefs) {
246			_SCErrorSet(kSCStatusFailed);
247			SCLog(_sc_verbose, LOG_ERR, CFSTR("SCPreferencesCommitChanges CFPropertyListCreateData() failed"));
248			SCLog(_sc_verbose, LOG_ERR, CFSTR("  prefs = %s"), path);
249			CFAllocatorDeallocate(NULL, thePath);
250			(void) close(fd);
251			goto done;
252		}
253		if (writen(fd, (const void *)CFDataGetBytePtr(newPrefs), CFDataGetLength(newPrefs)) == -1) {
254			_SCErrorSet(errno);
255			SCLog(_sc_verbose, LOG_ERR, CFSTR("SCPreferencesCommitChanges write() failed: %s"), strerror(errno));
256			SCLog(_sc_verbose, LOG_ERR, CFSTR("  path = %s"), thePath);
257			(void) unlink(thePath);
258			CFAllocatorDeallocate(NULL, thePath);
259			(void) close(fd);
260			CFRelease(newPrefs);
261			goto done;
262		}
263
264		/* new preferences have been written */
265		if (close(fd) == -1) {
266			_SCErrorSet(errno);
267			SCLog(_sc_verbose, LOG_ERR, CFSTR("SCPreferencesCommitChanges close() failed: %s"), strerror(errno));
268			SCLog(_sc_verbose, LOG_ERR, CFSTR("  path = %s"), thePath);
269			(void) unlink(thePath);
270			CFAllocatorDeallocate(NULL, thePath);
271			CFRelease(newPrefs);
272			goto done;
273		}
274		CFRelease(newPrefs);
275
276		/* rename new->old */
277		if (rename(thePath, path) == -1) {
278			_SCErrorSet(errno);
279			SCLog(_sc_verbose, LOG_ERR, CFSTR("SCPreferencesCommitChanges rename() failed: %s"), strerror(errno));
280			SCLog(_sc_verbose, LOG_ERR, CFSTR("  path = %s --> %s"), thePath, path);
281			CFAllocatorDeallocate(NULL, thePath);
282			goto done;
283		}
284		CFAllocatorDeallocate(NULL, thePath);
285
286		if (prefsPrivate->newPath) {
287			/* prefs file saved in "new" directory */
288			(void) unlink(prefsPrivate->path);
289			(void) symlink(prefsPrivate->newPath, prefsPrivate->path);
290			CFAllocatorDeallocate(NULL, prefsPrivate->path);
291			prefsPrivate->path = path;
292			prefsPrivate->newPath = NULL;
293		}
294
295		/* grab the new signature */
296		if (stat(path, &statBuf) == -1) {
297			_SCErrorSet(errno);
298			SCLog(_sc_verbose, LOG_ERR, CFSTR("SCPreferencesCommitChanges stat() failed: %s"), strerror(errno));
299			SCLog(_sc_verbose, LOG_ERR, CFSTR("  path = %s"), thePath);
300			goto done;
301		}
302	} else {
303		/* remove the empty .plist */
304		unlink(path);
305
306		/* init the new signature */
307		bzero(&statBuf, sizeof(statBuf));
308	}
309
310	/* update signature */
311	if (prefsPrivate->signature != NULL) CFRelease(prefsPrivate->signature);
312	prefsPrivate->signature = __SCPSignatureFromStatbuf(&statBuf);
313
314    committed :
315
316	/* post notification */
317	if (prefsPrivate->session == NULL) {
318		ok = TRUE;
319	} else {
320		ok = SCDynamicStoreNotifyValue(prefsPrivate->session, prefsPrivate->sessionKeyCommit);
321		if (!ok) {
322			SCLog(_sc_verbose, LOG_ERR, CFSTR("SCPreferencesCommitChanges SCDynamicStoreNotifyValue() failed"));
323			_SCErrorSet(kSCStatusFailed);
324			goto done;
325		}
326	}
327
328	prefsPrivate->changed = FALSE;
329
330    done :
331
332	if (!wasLocked) {
333		uint32_t	status;
334
335		status = SCError();	// preserve status across unlock
336		(void) SCPreferencesUnlock(prefs);
337		_SCErrorSet(status);
338	}
339	return ok;
340}
341