mono/metadata/mono-security-windows.c

   1 /**
   2  * \file
   3  * Windows security support.
   4  *
   5  * Copyright 2016 Microsoft
   6  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
   7  */
   8 #include <config.h>
   9 #include <glib.h>
  10
  11 #if defined(HOST_WIN32)
  12 #include <winsock2.h>
  13 #include <windows.h>
  14 #include "mono/metadata/mono-security-windows-internals.h"
  15
  16 #if G_HAVE_API_SUPPORT(HAVE_CLASSIC_WINAPI_SUPPORT)
  17 #include <aclapi.h>
  18 #include <accctrl.h>
  19 #endif
  20
  21 #ifndef PROTECTED_DACL_SECURITY_INFORMATION
  22 #define PROTECTED_DACL_SECURITY_INFORMATION     0x80000000L
  23 #endif
  24
  25 #if G_HAVE_API_SUPPORT(HAVE_CLASSIC_WINAPI_SUPPORT)
  26 static gunichar2*
  27 GetSidName (gunichar2 *server, PSID sid, gint32 *size)
  28 {
  29         gunichar2 *uniname = NULL;
  30         DWORD cchName = 0;
  31         DWORD cchDomain = 0;
  32         SID_NAME_USE peUse; /* out */
  33
  34         LookupAccountSid (server, sid, NULL, &cchName, NULL,
  35                 &cchDomain, &peUse);
  36
  37         if ((cchName > 0) && (cchDomain > 0)) {
  38                 gunichar2 *user = g_malloc0 ((cchName + 1) * 2);
  39                 gunichar2 *domain = g_malloc0 ((cchDomain + 1) * 2);
  40
  41                 LookupAccountSid (server, sid, user, &cchName, domain,
  42                         &cchDomain, &peUse);
  43
  44                 if (cchName > 0) {
  45                         if (cchDomain > 0) {
  46                                 /* domain/machine name included (+ sepearator) */
  47                                 *size = cchName + cchDomain + 1;
  48                                 uniname = g_malloc0 ((*size + 1) * 2);
  49                                 memcpy (uniname, domain, cchDomain * 2);
  50                                 *(uniname + cchDomain) = '\\';
  51                                 memcpy (uniname + cchDomain + 1, user, cchName * 2);
  52                                 g_free (user);
  53                         }
  54                         else {
  55                                 /* no domain / machine */
  56                                 *size = cchName;
  57                                 uniname = user;
  58                         }
  59                 }
  60                 else {
  61                         /* nothing -> return NULL */
  62                         g_free (user);
  63                 }
  64
  65                 g_free (domain);
  66         }
  67
  68         return uniname;
  69 }
  70
  71 gpointer
  72 mono_security_principal_windows_identity_get_current_token (void)
  73 {
  74         gpointer token = NULL;
  75
  76         /* Note: This isn't a copy of the Token - we must not close it!!!
  77          * http://www.develop.com/kbrown/book/html/whatis_windowsprincipal.html
  78          */
  79
  80         /* thread may be impersonating somebody */
  81         if (OpenThreadToken (GetCurrentThread (), MAXIMUM_ALLOWED, 1, &token) == 0) {
  82                 /* if not take the process identity */
  83                 OpenProcessToken (GetCurrentProcess (), MAXIMUM_ALLOWED, &token);
  84         }
  85
  86         return token;
  87 }
  88
  89 gpointer
  90 ves_icall_System_Security_Principal_WindowsIdentity_GetCurrentToken (MonoError *error)
  91 {
  92         error_init (error);
  93         return mono_security_principal_windows_identity_get_current_token ();
  94 }
  95
  96 gint32
  97 mono_security_win_get_token_name (gpointer token, gunichar2 ** uniname)
  98 {
  99         gint32 size = 0;
 100
 101         GetTokenInformation (token, TokenUser, NULL, size, (PDWORD)&size);
 102         if (size > 0) {
 103                 TOKEN_USER *tu = g_malloc0 (size);
 104                 if (GetTokenInformation (token, TokenUser, tu, size, (PDWORD)&size)) {
 105                         *uniname = GetSidName (NULL, tu->User.Sid, &size);
 106                 }
 107                 g_free (tu);
 108         }
 109
 110         return size;
 111 }
 112 #endif /* G_HAVE_API_SUPPORT(HAVE_CLASSIC_WINAPI_SUPPORT) */
 113
 114 MonoStringHandle
 115 ves_icall_System_Security_Principal_WindowsIdentity_GetTokenName (gpointer token, MonoError *error)
 116 {
 117         MonoStringHandle result;
 118         gunichar2 *uniname = NULL;
 119         gint32 size = 0;
 120
 121         error_init (error);
 122
 123         size = mono_security_win_get_token_name (token, &uniname);
 124
 125         if (size > 0) {
 126                 result = mono_string_new_utf16_handle (mono_domain_get (), uniname, size, error);
 127         }
 128         else
 129                 result = mono_string_new_handle (mono_domain_get (), "", error);
 130
 131         if (uniname)
 132                 g_free (uniname);
 133
 134         return result;
 135 }
 136
 137 gpointer
 138 ves_icall_System_Security_Principal_WindowsIdentity_GetUserToken (MonoStringHandle username, MonoError *error)
 139 {
 140         error_init (error);
 141         gpointer token = NULL;
 142
 143         /* TODO: MS has something like this working in Windows 2003 (client and
 144          * server) but works only for domain accounts (so it's quite limiting).
 145          * http://www.develop.com/kbrown/book/html/howto_logonuser.html
 146          */
 147         g_warning ("Unsupported on Win32 (anyway requires W2K3 minimum)");
 148         return token;
 149 }
 150
 151 #if G_HAVE_API_SUPPORT(HAVE_CLASSIC_WINAPI_SUPPORT)
 152 MonoArray*
 153 ves_icall_System_Security_Principal_WindowsIdentity_GetRoles (gpointer token)
 154 {
 155         ERROR_DECL (error);
 156         MonoArray *array = NULL;
 157         MonoDomain *domain = mono_domain_get ();
 158
 159         gint32 size = 0;
 160
 161         GetTokenInformation (token, TokenGroups, NULL, size, (PDWORD)&size);
 162         if (size > 0) {
 163                 TOKEN_GROUPS *tg = g_malloc0 (size);
 164                 if (GetTokenInformation (token, TokenGroups, tg, size, (PDWORD)&size)) {
 165                         int i=0;
 166                         int num = tg->GroupCount;
 167
 168                         array = mono_array_new_checked (domain, mono_get_string_class (), num, error);
 169                         if (mono_error_set_pending_exception (error)) {
 170                                 g_free (tg);
 171                                 return NULL;
 172                         }
 173
 174                         for (i=0; i < num; i++) {
 175                                 gint32 size = 0;
 176                                 gunichar2 *uniname = GetSidName (NULL, tg->Groups [i].Sid, &size);
 177
 178                                 if (uniname) {
 179                                         MonoString *str = mono_string_new_utf16_checked (domain, uniname, size, error);
 180                                         if (!is_ok (error)) {
 181                                                 g_free (uniname);
 182                                                 g_free (tg);
 183                                                 mono_error_set_pending_exception (error);
 184                                                 return NULL;
 185                                         }
 186                                         mono_array_setref (array, i, str);
 187                                         g_free (uniname);
 188                                 }
 189                         }
 190                 }
 191                 g_free (tg);
 192         }
 193
 194         if (!array) {
 195                 /* return empty array of string, i.e. string [0] */
 196                 array = mono_array_new_checked (domain, mono_get_string_class (), 0, error);
 197                 mono_error_set_pending_exception (error);
 198         }
 199         return array;
 200 }
 201 #endif /* G_HAVE_API_SUPPORT(HAVE_CLASSIC_WINAPI_SUPPORT) */
 202
 203 gboolean
 204 ves_icall_System_Security_Principal_WindowsImpersonationContext_CloseToken (gpointer token)
 205 {
 206         gboolean result = TRUE;
 207         result = (CloseHandle (token) != 0);
 208         return result;
 209 }
 210
 211 #if G_HAVE_API_SUPPORT(HAVE_CLASSIC_WINAPI_SUPPORT)
 212 gpointer
 213 ves_icall_System_Security_Principal_WindowsImpersonationContext_DuplicateToken (gpointer token)
 214 {
 215         gpointer dupe = NULL;
 216
 217         if (DuplicateToken (token, SecurityImpersonation, &dupe) == 0) {
 218                 dupe = NULL;
 219         }
 220         return dupe;
 221 }
 222 #endif /* G_HAVE_API_SUPPORT(HAVE_CLASSIC_WINAPI_SUPPORT) */
 223
 224 gboolean
 225 ves_icall_System_Security_Principal_WindowsPrincipal_IsMemberOfGroupId (gpointer user, gpointer group)
 226 {
 227         gboolean result = FALSE;
 228
 229         /* The convertion from an ID to a string is done in managed code for Windows */
 230         g_warning ("IsMemberOfGroupId should never be called on Win32");
 231         return result;
 232 }
 233
 234 gboolean
 235 ves_icall_System_Security_Principal_WindowsPrincipal_IsMemberOfGroupName (gpointer user, MonoString *group)
 236 {
 237         gboolean result = FALSE;
 238
 239         /* Windows version use a cache built using WindowsIdentity._GetRoles */
 240         g_warning ("IsMemberOfGroupName should never be called on Win32");
 241         return result;
 242 }
 243
 244 #if G_HAVE_API_SUPPORT(HAVE_CLASSIC_WINAPI_SUPPORT)
 245 static PSID
 246 GetAdministratorsSid (void)
 247 {
 248         SID_IDENTIFIER_AUTHORITY admins = { SECURITY_NT_AUTHORITY };
 249         PSID pSid = NULL;
 250         if (!AllocateAndInitializeSid (&admins, 2, SECURITY_BUILTIN_DOMAIN_RID,
 251                 DOMAIN_ALIAS_RID_ADMINS, 0, 0, 0, 0, 0, 0, &pSid))
 252                 return NULL;
 253         /* Note: this SID must be freed with FreeSid () */
 254         return pSid;
 255 }
 256
 257 static PSID
 258 GetEveryoneSid (void)
 259 {
 260         SID_IDENTIFIER_AUTHORITY everyone = { SECURITY_WORLD_SID_AUTHORITY };
 261         PSID pSid = NULL;
 262         if (!AllocateAndInitializeSid (&everyone, 1, SECURITY_WORLD_RID, 0, 0, 0, 0, 0, 0, 0, &pSid))
 263                 return NULL;
 264         /* Note: this SID must be freed with FreeSid () */
 265         return pSid;
 266 }
 267
 268 static PSID
 269 GetCurrentUserSid (void)
 270 {
 271         PSID sid = NULL;
 272         guint32 size = 0;
 273         gpointer token = mono_security_principal_windows_identity_get_current_token ();
 274
 275         GetTokenInformation (token, TokenUser, NULL, size, (PDWORD)&size);
 276         if (size > 0) {
 277                 TOKEN_USER *tu = g_malloc0 (size);
 278                 if (GetTokenInformation (token, TokenUser, tu, size, (PDWORD)&size)) {
 279                         DWORD length = GetLengthSid (tu->User.Sid);
 280                         sid = (PSID) g_malloc0 (length);
 281                         if (!CopySid (length, sid, tu->User.Sid)) {
 282                                 g_free (sid);
 283                                 sid = NULL;
 284                         }
 285                 }
 286                 g_free (tu);
 287         }
 288         /* Note: this SID must be freed with g_free () */
 289         return sid;
 290 }
 291
 292 static ACCESS_MASK
 293 GetRightsFromSid (PSID sid, PACL acl)
 294 {
 295         ACCESS_MASK rights = 0;
 296         TRUSTEE trustee;
 297
 298         BuildTrusteeWithSidW (&trustee, sid);
 299         if (GetEffectiveRightsFromAcl (acl, &trustee, &rights) != ERROR_SUCCESS)
 300                 return 0;
 301
 302         return rights;
 303 }
 304
 305 gboolean
 306 mono_security_win_is_machine_protected (gunichar2 *path)
 307 {
 308         gboolean success = FALSE;
 309         PACL pDACL = NULL;
 310         PSECURITY_DESCRIPTOR pSD = NULL;
 311         PSID pEveryoneSid = NULL;
 312
 313         DWORD dwRes = GetNamedSecurityInfoW (path, SE_FILE_OBJECT, DACL_SECURITY_INFORMATION, NULL, NULL, &pDACL, NULL, &pSD);
 314         if (dwRes != ERROR_SUCCESS)
 315                 return FALSE;
 316
 317         /* We check that Everyone is still limited to READ-ONLY -
 318         but not if new entries have been added by an Administrator */
 319
 320         pEveryoneSid = GetEveryoneSid ();
 321         if (pEveryoneSid) {
 322                 ACCESS_MASK rights = GetRightsFromSid (pEveryoneSid, pDACL);
 323                 /* http://msdn.microsoft.com/library/en-us/security/security/generic_access_rights.asp?frame=true */
 324                 success = (rights == (READ_CONTROL | SYNCHRONIZE | FILE_READ_DATA | FILE_READ_EA | FILE_READ_ATTRIBUTES));
 325                 FreeSid (pEveryoneSid);
 326         }
 327         /* Note: we don't need to check our own access -
 328         we'll know soon enough when reading the file */
 329
 330         if (pSD)
 331                 LocalFree (pSD);
 332
 333         return success;
 334 }
 335
 336 gboolean
 337 mono_security_win_is_user_protected (gunichar2 *path)
 338 {
 339         gboolean success = FALSE;
 340         PACL pDACL = NULL;
 341         PSID pEveryoneSid = NULL;
 342         PSECURITY_DESCRIPTOR pSecurityDescriptor = NULL;
 343
 344         DWORD dwRes = GetNamedSecurityInfoW (path, SE_FILE_OBJECT,
 345                 DACL_SECURITY_INFORMATION, NULL, NULL, &pDACL, NULL, &pSecurityDescriptor);
 346         if (dwRes != ERROR_SUCCESS)
 347                 return FALSE;
 348
 349         /* We check that our original entries in the ACL are in place -
 350         but not if new entries have been added by the user */
 351
 352         /* Everyone should be denied */
 353         pEveryoneSid = GetEveryoneSid ();
 354         if (pEveryoneSid) {
 355                 ACCESS_MASK rights = GetRightsFromSid (pEveryoneSid, pDACL);
 356                 success = (rights == 0);
 357                 FreeSid (pEveryoneSid);
 358         }
 359         /* Note: we don't need to check our own access -
 360         we'll know soon enough when reading the file */
 361
 362         if (pSecurityDescriptor)
 363                 LocalFree (pSecurityDescriptor);
 364
 365         return success;
 366 }
 367
 368 gboolean
 369 mono_security_win_protect_machine (gunichar2 *path)
 370 {
 371         PSID pEveryoneSid = GetEveryoneSid ();
 372         PSID pAdminsSid = GetAdministratorsSid ();
 373         DWORD retval = -1;
 374
 375         if (pEveryoneSid && pAdminsSid) {
 376                 PACL pDACL = NULL;
 377                 EXPLICIT_ACCESS ea [2];
 378                 ZeroMemory (&ea, 2 * sizeof (EXPLICIT_ACCESS));
 379
 380                 /* grant all access to the BUILTIN\Administrators group */
 381                 BuildTrusteeWithSidW (&ea [0].Trustee, pAdminsSid);
 382                 ea [0].grfAccessPermissions = GENERIC_ALL;
 383                 ea [0].grfAccessMode = SET_ACCESS;
 384                 ea [0].grfInheritance = SUB_CONTAINERS_AND_OBJECTS_INHERIT;
 385                 ea [0].Trustee.TrusteeForm = TRUSTEE_IS_SID;
 386                 ea [0].Trustee.TrusteeType = TRUSTEE_IS_WELL_KNOWN_GROUP;
 387
 388                 /* read-only access everyone */
 389                 BuildTrusteeWithSidW (&ea [1].Trustee, pEveryoneSid);
 390                 ea [1].grfAccessPermissions = GENERIC_READ;
 391                 ea [1].grfAccessMode = SET_ACCESS;
 392                 ea [1].grfInheritance = SUB_CONTAINERS_AND_OBJECTS_INHERIT;
 393                 ea [1].Trustee.TrusteeForm = TRUSTEE_IS_SID;
 394                 ea [1].Trustee.TrusteeType = TRUSTEE_IS_WELL_KNOWN_GROUP;
 395
 396                 retval = SetEntriesInAcl (2, ea, NULL, &pDACL);
 397                 if (retval == ERROR_SUCCESS) {
 398                         /* with PROTECTED_DACL_SECURITY_INFORMATION we */
 399                         /* remove any existing ACL (like inherited ones) */
 400                         retval = SetNamedSecurityInfo (path, SE_FILE_OBJECT,
 401                                 DACL_SECURITY_INFORMATION | PROTECTED_DACL_SECURITY_INFORMATION,
 402                                 NULL, NULL, pDACL, NULL);
 403                 }
 404                 if (pDACL)
 405                         LocalFree (pDACL);
 406         }
 407
 408         if (pEveryoneSid)
 409                 FreeSid (pEveryoneSid);
 410         if (pAdminsSid)
 411                 FreeSid (pAdminsSid);
 412         return (retval == ERROR_SUCCESS);
 413 }
 414
 415 gboolean
 416 mono_security_win_protect_user (gunichar2 *path)
 417 {
 418         DWORD retval = -1;
 419
 420         PSID pCurrentSid = GetCurrentUserSid ();
 421         if (pCurrentSid) {
 422                 PACL pDACL = NULL;
 423                 EXPLICIT_ACCESS ea;
 424                 ZeroMemory (&ea, sizeof (EXPLICIT_ACCESS));
 425
 426                 /* grant exclusive access to the current user */
 427                 BuildTrusteeWithSidW (&ea.Trustee, pCurrentSid);
 428                 ea.grfAccessPermissions = GENERIC_ALL;
 429                 ea.grfAccessMode = SET_ACCESS;
 430                 ea.grfInheritance = SUB_CONTAINERS_AND_OBJECTS_INHERIT;
 431                 ea.Trustee.TrusteeForm = TRUSTEE_IS_SID;
 432                 ea.Trustee.TrusteeType = TRUSTEE_IS_USER;
 433
 434                 retval = SetEntriesInAcl (1, &ea, NULL, &pDACL);
 435                 if (retval == ERROR_SUCCESS) {
 436                         /* with PROTECTED_DACL_SECURITY_INFORMATION we
 437                            remove any existing ACL (like inherited ones) */
 438                         retval = SetNamedSecurityInfo (path, SE_FILE_OBJECT,
 439                                 DACL_SECURITY_INFORMATION | PROTECTED_DACL_SECURITY_INFORMATION,
 440                                 NULL, NULL, pDACL, NULL);
 441                 }
 442
 443                 if (pDACL)
 444                         LocalFree (pDACL);
 445                 g_free (pCurrentSid); /* g_malloc0 */
 446         }
 447
 448         return (retval == ERROR_SUCCESS);
 449 }
 450 #endif /* G_HAVE_API_SUPPORT(HAVE_CLASSIC_WINAPI_SUPPORT) */
 451
 452 MonoBoolean
 453 ves_icall_Mono_Security_Cryptography_KeyPairPersistence_CanSecure (MonoString *root)
 454 {
 455         gint32 flags;
 456
 457         /* ACL are nice... unless you have FAT or other uncivilized filesystem */
 458         if (!GetVolumeInformation (mono_string_chars (root), NULL, 0, NULL, NULL, (LPDWORD)&flags, NULL, 0))
 459                 return FALSE;
 460         return ((flags & FS_PERSISTENT_ACLS) == FS_PERSISTENT_ACLS);
 461 }
 462
 463 MonoBoolean
 464 ves_icall_Mono_Security_Cryptography_KeyPairPersistence_IsMachineProtected (MonoString *path)
 465 {
 466         gboolean ret = FALSE;
 467
 468         /* no one, but the owner, should have write access to the directory */
 469         ret = mono_security_win_is_machine_protected (mono_string_chars (path));
 470         return (MonoBoolean)ret;
 471 }
 472
 473 MonoBoolean
 474 ves_icall_Mono_Security_Cryptography_KeyPairPersistence_IsUserProtected (MonoString *path)
 475 {
 476         gboolean ret = FALSE;
 477
 478         /* no one, but the user, should have access to the directory */
 479         ret = mono_security_win_is_user_protected (mono_string_chars (path));
 480         return (MonoBoolean)ret;
 481 }
 482
 483 MonoBoolean
 484 ves_icall_Mono_Security_Cryptography_KeyPairPersistence_ProtectMachine (MonoString *path)
 485 {
 486         gboolean ret = FALSE;
 487
 488         /* read/write to owner, read to everyone else */
 489         ret = mono_security_win_protect_machine (mono_string_chars (path));
 490         return (MonoBoolean)ret;
 491 }
 492
 493 MonoBoolean
 494 ves_icall_Mono_Security_Cryptography_KeyPairPersistence_ProtectUser (MonoString *path)
 495 {
 496         gboolean ret = FALSE;
 497
 498         /* read/write to user, no access to everyone else */
 499         ret = mono_security_win_protect_user (mono_string_chars (path));
 500         return (MonoBoolean)ret;
 501 }
 502 #endif /* HOST_WIN32 */