OSX/libsecurity_utilities/lib/simpleprefs.cpp

   1 /*
   2  * Copyright (c) 2002-2004,2011,2014 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  * simpleprefs.cpp - plist support for a bare bones Preferences implementation,
  26  *                 using only Darwin-avaialble CoreFoundation classes.
  27  */
  28
  29 #include "simpleprefs.h"
  30 #include "errors.h"
  31 #include <sys/param.h>
  32 #include <stdlib.h>
  33 #include <assert.h>
  34 #include <stdexcept>
  35 #include <security_utilities/debugging.h>
  36 #include <CoreFoundation/CFData.h>
  37 #include <CoreFoundation/CFNumber.h>
  38 #include <CoreFoundation/CFURLAccess.h>
  39 #include <CoreFoundation/CFPropertyList.h>
  40 #include <sys/stat.h>
  41
  42 #define prefsDebug(args...)             secinfo("simpleprefs", ## args)
  43
  44 #define kSecUserPrefsDir                        "Library/Preferences"           /* relative to $HOME */
  45 #define kSecSystemPrefsDir                      "/Library/Preferences"
  46
  47 #pragma mark ----- (immutable) Dictionary -----
  48
  49 static void pathForDomain(const char *domain, Dictionary::UserOrSystem userSys, std::string &path)
  50 {
  51         path.clear();
  52         if(userSys == Dictionary::US_User) {
  53                 const char *home = getenv("HOME");
  54                 if(home == NULL) {
  55                         home = "";
  56                 }
  57                 path = std::string(home) + "/" + kSecUserPrefsDir + "/" + domain + ".plist";
  58         }
  59         else {
  60                 path = std::string(kSecSystemPrefsDir) + "/" + domain + ".plist";
  61         }
  62 }
  63
  64 static bool FileExists(const char* s)
  65 {
  66         // this isn't very efficient, either, but orders are to get rid of exceptions...
  67         struct stat st;
  68         int result = stat(s, &st);
  69         return result == 0;
  70 }
  71
  72 // use factory functions to create the dictionaries so that we can test for the presence of the dictionaries
  73 // without throwing
  74 Dictionary* Dictionary::CreateDictionary(const char* path)
  75 {
  76         if (!FileExists(path))
  77         {
  78                 return NULL;
  79         }
  80         else
  81         {
  82                 return new Dictionary(path);
  83         }
  84 }
  85
  86 Dictionary* Dictionary::CreateDictionary(const char* domain, UserOrSystem userSys, bool loose)
  87 {
  88         std::string path;
  89         pathForDomain(domain, userSys, path);
  90         bool exists = FileExists(path.c_str());
  91         if (!loose && !exists)
  92         {
  93                 return NULL;
  94         }
  95
  96         if (!exists)
  97         {
  98                 return new Dictionary();
  99         }
 100
 101         return new Dictionary(path.c_str());
 102 }
 103
 104 Dictionary::Dictionary() : mDict(NULL)
 105 {
 106 }
 107
 108 Dictionary::Dictionary(
 109         const char              *path)
 110                 : mDict(NULL)
 111 {
 112         initFromFile(path);
 113 }
 114
 115 Dictionary::Dictionary(
 116         CFDictionaryRef dict)
 117                 : mDict(dict)
 118 {
 119         if (mDict)
 120                 CFRetain(mDict);
 121 }
 122
 123 Dictionary::~Dictionary()
 124 {
 125         if(mDict) {
 126                 CFRelease(mDict);
 127         }
 128 }
 129
 130 /* basic lookup */
 131 const void *Dictionary::getValue(
 132         CFStringRef key)
 133 {
 134         return CFDictionaryGetValue(dict(), key);
 135 }
 136
 137 /* lookup, value must be CFString (we check) */
 138 CFStringRef Dictionary::getStringValue(
 139         CFStringRef     key)
 140 {
 141         CFStringRef val = (CFStringRef)CFDictionaryGetValue(dict(), key);
 142         if(val == NULL) {
 143                 return NULL;
 144         }
 145         if(CFGetTypeID(val) != CFStringGetTypeID()) {
 146                 return NULL;
 147         }
 148         return val;
 149 }
 150
 151 /* lookup, value must be CFData (we check) */
 152 CFDataRef Dictionary::getDataValue(
 153         CFStringRef     key)
 154 {
 155         CFDataRef val = (CFDataRef)CFDictionaryGetValue(dict(), key);
 156         if(val == NULL) {
 157                 return NULL;
 158         }
 159         if(CFGetTypeID(val) != CFDataGetTypeID()) {
 160                 return NULL;
 161         }
 162         return val;
 163 }
 164
 165 /* lookup, value must be CFDictionary (we check) */
 166 CFDictionaryRef Dictionary::getDictValue(
 167         CFStringRef key)
 168 {
 169         CFDictionaryRef val = (CFDictionaryRef)CFDictionaryGetValue(dict(), key);
 170         if(val == NULL) {
 171                 return NULL;
 172         }
 173         if(CFGetTypeID(val) != CFDictionaryGetTypeID()) {
 174                 return NULL;
 175         }
 176         return val;
 177 }
 178
 179 /*
 180  * Lookup, value is a dictionary, we return value as Dictionary
 181  * if found, else return NULL.
 182  */
 183 Dictionary *Dictionary::copyDictValue(
 184         CFStringRef key)
 185 {
 186         CFDictionaryRef cfDict = getDictValue(key);
 187         if(cfDict == NULL) {
 188                 return NULL;
 189         }
 190         Dictionary *rtnDict = new Dictionary(cfDict);
 191         /*
 192          * mDict has one ref count
 193          * cfDict has one ref count
 194          */
 195         return rtnDict;
 196 }
 197
 198 /*
 199  * boolean lookup, tolerate many different forms of value.
 200  * Default if value not present is false.
 201  */
 202 bool Dictionary::getBoolValue(
 203         CFStringRef key)
 204 {
 205         CFTypeRef val = CFDictionaryGetValue(dict(), key);
 206         if(val == NULL) {
 207                 return false;
 208         }
 209         CFComparisonResult res;
 210         if(CFGetTypeID(val) == CFStringGetTypeID()) {
 211                 res = CFStringCompare((CFStringRef)val, CFSTR("YES"),
 212                                 kCFCompareCaseInsensitive);
 213                 if(res == kCFCompareEqualTo) {
 214                         return true;
 215                 }
 216                 else {
 217                         return false;
 218                 }
 219         }
 220         if(CFGetTypeID(val) == CFBooleanGetTypeID()) {
 221                 return CFBooleanGetValue((CFBooleanRef)val) ? true : false;
 222         }
 223         if(CFGetTypeID(val) == CFNumberGetTypeID()) {
 224                 char cval = 0;
 225                 CFNumberGetValue((CFNumberRef)val, kCFNumberCharType, &cval);
 226                 return (cval == 0) ? false : true;
 227         }
 228         return false;
 229 }
 230
 231 CFIndex Dictionary::count()
 232 {
 233         return CFDictionaryGetCount(dict());
 234 }
 235
 236 void Dictionary::setDict(
 237         CFDictionaryRef newDict)
 238 {
 239         if(mDict != NULL)
 240                 CFRelease(mDict);
 241         mDict = newDict;
 242         CFRetain(mDict);
 243 }
 244
 245 /* fundamental routine to init from a plist file; throws a UnixError on error */
 246 void Dictionary::initFromFile(
 247         const char *path,
 248         bool            loose /* = false */)
 249 {
 250         if(mDict != NULL) {
 251                 CFRelease(mDict);
 252                 mDict = NULL;
 253         }
 254         CFURLRef url = CFURLCreateFromFileSystemRepresentation(NULL, (const UInt8 *)path,
 255                 strlen(path), false);
 256         if(url == NULL) {
 257         UnixError::throwMe(EIO);
 258         }
 259
 260         CFDataRef fileData = NULL;
 261         CFPropertyListRef propList = NULL;
 262         CFStringRef errorString = NULL;
 263         SInt32 errorCode;
 264
 265         Boolean success = CFURLCreateDataAndPropertiesFromResource(
 266                 NULL,
 267                 url,
 268                 &fileData,
 269                 NULL,                   // properties
 270                 NULL,                   // desiredProperties
 271                 &errorCode);
 272         CFRelease(url);
 273         if(success) {
 274                 propList = CFPropertyListCreateFromXMLData(
 275                         NULL,
 276                         fileData,
 277                         kCFPropertyListImmutable,
 278                         &errorString);
 279                 if(propList != NULL) {
 280                         /*
 281                          * Note don't use setDict() here to avoid the extra
 282                          * refcount that would entail. We own the dictionary now.
 283                          */
 284                         mDict = (CFDictionaryRef)propList;
 285                 }
 286                 else {
 287                         success = false;
 288                 }
 289         }
 290         if(fileData != NULL) {
 291                 CFRelease(fileData);
 292         }
 293         if(errorString != NULL) {
 294                 CFRelease(errorString);
 295         }
 296         if(!success) {
 297                 if (loose)
 298                         return;
 299                 else
 300                         UnixError::throwMe(EIO);
 301         }
 302 }
 303
 304 #pragma mark ----- Mutable Dictionary -----
 305
 306 // factory functions
 307 MutableDictionary* MutableDictionary::CreateMutableDictionary(const char* fileName)
 308 {
 309         std::string path;
 310
 311         if (!FileExists(path.c_str()))
 312         {
 313                 return NULL;
 314         }
 315         else
 316         {
 317                 return new MutableDictionary(path.c_str());
 318         }
 319 }
 320
 321 MutableDictionary* MutableDictionary::CreateMutableDictionary(const char *domain, UserOrSystem userSys)
 322 {
 323         std::string path;
 324         pathForDomain(domain, userSys, path);
 325
 326         if (!FileExists(path.c_str()))
 327         {
 328                 return NULL;
 329         }
 330
 331         return new MutableDictionary(path.c_str());
 332 }
 333
 334 /* Create an empty mutable dictionary */
 335 MutableDictionary::MutableDictionary()
 336         : Dictionary((CFDictionaryRef)CFDictionaryCreateMutable(NULL, 0,
 337                 &kCFCopyStringDictionaryKeyCallBacks,
 338                 &kCFTypeDictionaryValueCallBacks))
 339 {
 340         /* lose one of those two retain counts.... */
 341         CFRelease(mDict);
 342 }
 343
 344 MutableDictionary::MutableDictionary(
 345         const char              *filename)
 346                 : Dictionary(filename)
 347 {
 348         /*
 349          * Dictionary's contructor read the plist from disk. Now
 350          * replace that dictionary with a mutable copy.
 351          */
 352         makeMutable();
 353 }
 354
 355 /*
 356  * Create from existing CFDictionary (OR CFMutableDictionary).
 357  * I don't see any way the CF runtime will let us differentiate an
 358  * immutable from a mutable dictionary here, so caller has to tell us.
 359  */
 360 MutableDictionary::MutableDictionary(
 361         CFDictionaryRef dict,
 362         bool isMutable)
 363                 : Dictionary(dict)
 364 {
 365         if(!isMutable) {
 366                 makeMutable();
 367         }
 368 }
 369
 370 MutableDictionary::~MutableDictionary()
 371 {
 372         /* nothing for now */
 373 }
 374
 375 /*
 376  * Lookup, value must be CFDictionary (we check). We return a
 377  * mutable copy, or if key not found, we return a new mutable dictionary
 378  * with a ref count of one.
 379  * If you want a NULL return if it's not there, use getDictValue().
 380  */
 381 CFMutableDictionaryRef MutableDictionary::getMutableDictValue(
 382         CFStringRef key)
 383 {
 384         CFDictionaryRef dict = getDictValue(key);
 385         if(dict == NULL) {
 386                 prefsDebug("getMutableDictValue returning new empty dict; this %p", this);
 387                 return CFDictionaryCreateMutable(NULL, 0,
 388                                         &kCFCopyStringDictionaryKeyCallBacks,
 389                                         &kCFTypeDictionaryValueCallBacks);
 390         }
 391         else {
 392                 prefsDebug("getMutableDictValue returning copy; this %p", this);
 393                 return CFDictionaryCreateMutableCopy(NULL, 0, dict);
 394         }
 395 }
 396
 397 /*
 398  * Lookup, value is a dictionary, we return a MutableDictionary, even if
 399  * no value found.
 400  */
 401 MutableDictionary *MutableDictionary::copyMutableDictValue(
 402         CFStringRef key)
 403 {
 404         CFMutableDictionaryRef cfDict = getMutableDictValue(key);
 405         assert(CFGetRetainCount(cfDict) == 1);
 406         MutableDictionary *rtnDict = new MutableDictionary(cfDict, true);
 407         CFRelease(cfDict);
 408         /* rtnDict->mDict now holds the only ref count */
 409         return rtnDict;
 410 }
 411
 412 /*
 413  * Basic setter. Does a replace if present, add if not present op.
 414  */
 415 void MutableDictionary::setValue(
 416         CFStringRef             key,
 417         CFTypeRef               val)
 418 {
 419         CFDictionarySetValue(mutableDict(), key, val);
 420 }
 421
 422 /*
 423  * Set key/value pair, data as CFData in the dictionary but passed to us as CSSM_DATA.
 424  */
 425 void MutableDictionary::setDataValue(
 426         CFStringRef             key,
 427         const void *valData, CFIndex valLength)
 428 {
 429         CFDataRef cfVal = CFDataCreate(NULL, reinterpret_cast<const UInt8 *>(valData), valLength);
 430         setValue(key, cfVal);
 431         CFRelease(cfVal);
 432 }
 433
 434 /* remove key/value, if present; not an error if it's not */
 435 void MutableDictionary::removeValue(
 436         CFStringRef             key)
 437 {
 438         CFDictionaryRemoveValue(mutableDict(), key);
 439 }
 440
 441 /* write as XML property list, both return true on success */
 442 bool MutableDictionary::writePlistToFile(
 443         const char      *path)
 444 {
 445         assert(mDict != NULL);
 446         CFURLRef url = CFURLCreateFromFileSystemRepresentation(NULL, (const UInt8 *)path,
 447                 strlen(path), false);
 448         if(url == NULL) {
 449         UnixError::throwMe(EIO);
 450         }
 451
 452         CFDataRef xmlData = CFPropertyListCreateXMLData(NULL, dict());
 453         bool ourRtn = false;
 454         SInt32 errorCode;
 455         if(xmlData == NULL) {
 456                 goto errOut;
 457         }
 458         if(CFURLWriteDataAndPropertiesToResource(url, xmlData, NULL, &errorCode)) {
 459                 ourRtn = true;
 460         }
 461 errOut:
 462         if(url) {
 463                 CFRelease(url);
 464         }
 465         if(xmlData) {
 466                 CFRelease(xmlData);
 467         }
 468         return ourRtn;
 469 }
 470
 471 /* write XML property list to preferences file */
 472 bool MutableDictionary::writePlistToPrefs(
 473         const char              *domain,                // e.g., com.apple.security
 474         UserOrSystem    userSys)                // US_User  : ~/Library/Preferences/domain.plist
 475                                                                         // US_System: /Library/Preferences/domain.plist
 476 {
 477         std::string path;
 478         pathForDomain(domain, userSys, path);
 479         return writePlistToFile(path.c_str());
 480 }
 481
 482 /*
 483  * Called after Dictionary reads plist from file, resulting in an immutable
 484  * mDict. We replace that with a mutable copy.
 485  */
 486 void MutableDictionary::makeMutable()
 487 {
 488         CFMutableDictionaryRef mutDict = CFDictionaryCreateMutableCopy(NULL, 0, dict());
 489         if(mutDict == NULL) {
 490                 throw std::bad_alloc();
 491         }
 492         setDict(mutDict);
 493         /* we own the dictionary now */
 494         CFRelease(mutDict);
 495 }
 496