source3/modules/vfs_posixacl.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    VFS module to get and set posix acls
   4    Copyright (C) Volker Lendecke 2006
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "system/filesys.h"
  22 #include "smbd/smbd.h"
  23 #include "modules/vfs_posixacl.h"
  24
  25 /* prototypes for static functions first - for clarity */
  26
  27 static bool smb_ace_to_internal(acl_entry_t posix_ace,
  28                                 struct smb_acl_entry *ace);
  29 static struct smb_acl_t *smb_acl_to_internal(acl_t acl, TALLOC_CTX *mem_ctx);
  30 static int smb_acl_set_mode(acl_entry_t entry, SMB_ACL_PERM_T perm);
  31 static acl_t smb_acl_to_posix(const struct smb_acl_t *acl);
  32
  33
  34 /* public functions - the api */
  35
  36 SMB_ACL_T posixacl_sys_acl_get_fd(vfs_handle_struct *handle,
  37                                   files_struct *fsp,
  38                                   SMB_ACL_TYPE_T type,
  39                                   TALLOC_CTX *mem_ctx)
  40 {
  41         struct smb_acl_t *result;
  42         acl_t acl = NULL;
  43         acl_type_t acl_type;
  44
  45         switch(type) {
  46         case SMB_ACL_TYPE_ACCESS:
  47                 acl_type = ACL_TYPE_ACCESS;
  48                 break;
  49         case SMB_ACL_TYPE_DEFAULT:
  50                 acl_type = ACL_TYPE_DEFAULT;
  51                 break;
  52         default:
  53                 errno = EINVAL;
  54                 return NULL;
  55         }
  56         if (!fsp->fsp_flags.is_pathref && (acl_type == ACL_TYPE_ACCESS)) {
  57                 /* POSIX API only allows ACL_TYPE_ACCESS fetched on fd. */
  58                 acl = acl_get_fd(fsp_get_io_fd(fsp));
  59         } else if (fsp->fsp_flags.have_proc_fds) {
  60                 int fd = fsp_get_pathref_fd(fsp);
  61                 struct sys_proc_fd_path_buf buf;
  62
  63                 acl = acl_get_file(sys_proc_fd_path(fd, &buf), acl_type);
  64         } else {
  65                 /*
  66                  * This is no longer a handle based call.
  67                  */
  68                 acl = acl_get_file(fsp->fsp_name->base_name, acl_type);
  69         }
  70         if (acl == NULL) {
  71                 return NULL;
  72         }
  73
  74         result = smb_acl_to_internal(acl, mem_ctx);
  75         acl_free(acl);
  76         return result;
  77 }
  78
  79 int posixacl_sys_acl_set_fd(vfs_handle_struct *handle,
  80                             files_struct *fsp,
  81                             SMB_ACL_TYPE_T type,
  82                             SMB_ACL_T theacl)
  83 {
  84         int res;
  85         acl_t acl = smb_acl_to_posix(theacl);
  86         acl_type_t acl_type;
  87         int fd = fsp_get_pathref_fd(fsp);
  88
  89         if (acl == NULL) {
  90                 return -1;
  91         }
  92
  93         switch(type) {
  94         case SMB_ACL_TYPE_ACCESS:
  95                 acl_type = ACL_TYPE_ACCESS;
  96                 break;
  97         case SMB_ACL_TYPE_DEFAULT:
  98                 acl_type = ACL_TYPE_DEFAULT;
  99                 break;
 100         default:
 101                 acl_free(acl);
 102                 errno = EINVAL;
 103                 return -1;
 104         }
 105
 106         if (!fsp->fsp_flags.is_pathref && type == SMB_ACL_TYPE_ACCESS) {
 107                 res = acl_set_fd(fd, acl);
 108         } else if (fsp->fsp_flags.have_proc_fds) {
 109                 struct sys_proc_fd_path_buf buf;
 110
 111                 res = acl_set_file(sys_proc_fd_path(fd, &buf), acl_type, acl);
 112         } else {
 113                 /*
 114                  * This is no longer a handle based call.
 115                  */
 116                 res = acl_set_file(fsp->fsp_name->base_name,
 117                                    acl_type,
 118                                    acl);
 119         }
 120
 121         acl_free(acl);
 122         return res;
 123 }
 124
 125 int posixacl_sys_acl_delete_def_fd(vfs_handle_struct *handle,
 126                                 files_struct *fsp)
 127 {
 128         if (fsp->fsp_flags.have_proc_fds) {
 129                 int fd = fsp_get_pathref_fd(fsp);
 130                 struct sys_proc_fd_path_buf buf;
 131
 132                 return acl_delete_def_file(sys_proc_fd_path(fd, &buf));
 133         }
 134
 135         /*
 136          * This is no longer a handle based call.
 137          */
 138         return acl_delete_def_file(fsp->fsp_name->base_name);
 139 }
 140
 141 /* private functions */
 142
 143 static bool smb_ace_to_internal(acl_entry_t posix_ace,
 144                                 struct smb_acl_entry *ace)
 145 {
 146         acl_tag_t tag;
 147         acl_permset_t permset;
 148
 149         if (acl_get_tag_type(posix_ace, &tag) != 0) {
 150                 DEBUG(0, ("smb_acl_get_tag_type failed\n"));
 151                 return False;
 152         }
 153
 154         switch(tag) {
 155         case ACL_USER:
 156                 ace->a_type = SMB_ACL_USER;
 157                 break;
 158         case ACL_USER_OBJ:
 159                 ace->a_type = SMB_ACL_USER_OBJ;
 160                 break;
 161         case ACL_GROUP:
 162                 ace->a_type = SMB_ACL_GROUP;
 163                 break;
 164         case ACL_GROUP_OBJ:
 165                 ace->a_type = SMB_ACL_GROUP_OBJ;
 166                 break;
 167         case ACL_OTHER:
 168                 ace->a_type = SMB_ACL_OTHER;
 169                 break;
 170         case ACL_MASK:
 171                 ace->a_type = SMB_ACL_MASK;
 172                 break;
 173 #ifdef HAVE_ACL_EVERYONE
 174         case ACL_EVERYONE:
 175                 DEBUG(1, ("ACL tag type ACL_EVERYONE. FreeBSD with ZFS? Use 'vfs objects = zfsacl'\n"));
 176                 return false;
 177 #endif
 178         default:
 179                 DEBUG(0, ("unknown tag type %d\n", (unsigned int)tag));
 180                 return False;
 181         }
 182         switch(ace->a_type) {
 183         case SMB_ACL_USER: {
 184                 uid_t *puid = (uid_t *)acl_get_qualifier(posix_ace);
 185                 if (puid == NULL) {
 186                         DEBUG(0, ("smb_acl_get_qualifier failed\n"));
 187                         return False;
 188                 }
 189                 ace->info.user.uid = *puid;
 190                 acl_free(puid);
 191                 break;
 192         }
 193
 194         case SMB_ACL_GROUP: {
 195                 gid_t *pgid = (uid_t *)acl_get_qualifier(posix_ace);
 196                 if (pgid == NULL) {
 197                         DEBUG(0, ("smb_acl_get_qualifier failed\n"));
 198                         return False;
 199                 }
 200                 ace->info.group.gid = *pgid;
 201                 acl_free(pgid);
 202                 break;
 203         }
 204         default:
 205                 break;
 206         }
 207         if (acl_get_permset(posix_ace, &permset) != 0) {
 208                 DEBUG(0, ("smb_acl_get_mode failed\n"));
 209                 return False;
 210         }
 211         ace->a_perm = 0;
 212 #ifdef HAVE_ACL_GET_PERM_NP
 213         ace->a_perm |= (acl_get_perm_np(permset, ACL_READ) ? SMB_ACL_READ : 0);
 214         ace->a_perm |= (acl_get_perm_np(permset, ACL_WRITE) ? SMB_ACL_WRITE : 0);
 215         ace->a_perm |= (acl_get_perm_np(permset, ACL_EXECUTE) ? SMB_ACL_EXECUTE : 0);
 216 #else
 217         ace->a_perm |= (acl_get_perm(permset, ACL_READ) ? SMB_ACL_READ : 0);
 218         ace->a_perm |= (acl_get_perm(permset, ACL_WRITE) ? SMB_ACL_WRITE : 0);
 219         ace->a_perm |= (acl_get_perm(permset, ACL_EXECUTE) ? SMB_ACL_EXECUTE : 0);
 220 #endif
 221         return True;
 222 }
 223
 224 static struct smb_acl_t *smb_acl_to_internal(acl_t acl, TALLOC_CTX *mem_ctx)
 225 {
 226         struct smb_acl_t *result = sys_acl_init(mem_ctx);
 227         int entry_id = ACL_FIRST_ENTRY;
 228         acl_entry_t e;
 229         if (result == NULL) {
 230                 return NULL;
 231         }
 232         while (acl_get_entry(acl, entry_id, &e) == 1) {
 233
 234                 entry_id = ACL_NEXT_ENTRY;
 235
 236                 result->acl = talloc_realloc(result, result->acl,
 237                                              struct smb_acl_entry, result->count+1);
 238                 if (result->acl == NULL) {
 239                         TALLOC_FREE(result);
 240                         DEBUG(0, ("talloc_realloc failed\n"));
 241                         errno = ENOMEM;
 242                         return NULL;
 243                 }
 244
 245                 if (!smb_ace_to_internal(e, &result->acl[result->count])) {
 246                         TALLOC_FREE(result);
 247                         return NULL;
 248                 }
 249
 250                 result->count += 1;
 251         }
 252         return result;
 253 }
 254
 255 static int smb_acl_set_mode(acl_entry_t entry, SMB_ACL_PERM_T perm)
 256 {
 257         int ret;
 258         acl_permset_t permset;
 259
 260         if ((ret = acl_get_permset(entry, &permset)) != 0) {
 261                 return ret;
 262         }
 263         if ((ret = acl_clear_perms(permset)) != 0) {
 264                 return ret;
 265         }
 266         if ((perm & SMB_ACL_READ) &&
 267             ((ret = acl_add_perm(permset, ACL_READ)) != 0)) {
 268                 return ret;
 269         }
 270         if ((perm & SMB_ACL_WRITE) &&
 271             ((ret = acl_add_perm(permset, ACL_WRITE)) != 0)) {
 272                 return ret;
 273         }
 274         if ((perm & SMB_ACL_EXECUTE) &&
 275             ((ret = acl_add_perm(permset, ACL_EXECUTE)) != 0)) {
 276                 return ret;
 277         }
 278
 279         return 0;
 280 }
 281
 282 static acl_t smb_acl_to_posix(const struct smb_acl_t *acl)
 283 {
 284         acl_t result;
 285         int i;
 286
 287         result = acl_init(acl->count);
 288         if (result == NULL) {
 289                 DEBUG(10, ("acl_init failed\n"));
 290                 return NULL;
 291         }
 292
 293         for (i=0; i<acl->count; i++) {
 294                 const struct smb_acl_entry *entry = &acl->acl[i];
 295                 acl_entry_t e;
 296                 acl_tag_t tag;
 297
 298                 if (acl_create_entry(&result, &e) != 0) {
 299                         DEBUG(1, ("acl_create_entry failed: %s\n",
 300                                   strerror(errno)));
 301                         goto fail;
 302                 }
 303
 304                 switch (entry->a_type) {
 305                 case SMB_ACL_USER:
 306                         tag = ACL_USER;
 307                         break;
 308                 case SMB_ACL_USER_OBJ:
 309                         tag = ACL_USER_OBJ;
 310                         break;
 311                 case SMB_ACL_GROUP:
 312                         tag = ACL_GROUP;
 313                         break;
 314                 case SMB_ACL_GROUP_OBJ:
 315                         tag = ACL_GROUP_OBJ;
 316                         break;
 317                 case SMB_ACL_OTHER:
 318                         tag = ACL_OTHER;
 319                         break;
 320                 case SMB_ACL_MASK:
 321                         tag = ACL_MASK;
 322                         break;
 323                 default:
 324                         DEBUG(1, ("Unknown tag value %d\n", entry->a_type));
 325                         goto fail;
 326                 }
 327
 328                 if (acl_set_tag_type(e, tag) != 0) {
 329                         DEBUG(10, ("acl_set_tag_type(%d) failed: %s\n",
 330                                    tag, strerror(errno)));
 331                         goto fail;
 332                 }
 333
 334                 switch (entry->a_type) {
 335                 case SMB_ACL_USER:
 336                         if (acl_set_qualifier(e, &entry->info.user.uid) != 0) {
 337                                 DEBUG(1, ("acl_set_qualifier failed: %s\n",
 338                                           strerror(errno)));
 339                                 goto fail;
 340                         }
 341                         break;
 342                 case SMB_ACL_GROUP:
 343                         if (acl_set_qualifier(e, &entry->info.group.gid) != 0) {
 344                                 DEBUG(1, ("acl_set_qualifier failed: %s\n",
 345                                           strerror(errno)));
 346                                 goto fail;
 347                         }
 348                         break;
 349                 default:        /* Shut up, compiler! :-) */
 350                         break;
 351                 }
 352
 353                 if (smb_acl_set_mode(e, entry->a_perm) != 0) {
 354                         goto fail;
 355                 }
 356         }
 357
 358         if (acl_valid(result) != 0) {
 359                 char *acl_string = sys_acl_to_text(acl, NULL);
 360                 DEBUG(0, ("smb_acl_to_posix: ACL %s is invalid for set (%s)\n",
 361                           acl_string, strerror(errno)));
 362                 SAFE_FREE(acl_string);
 363                 goto fail;
 364         }
 365
 366         return result;
 367
 368  fail:
 369         if (result != NULL) {
 370                 acl_free(result);
 371         }
 372         return NULL;
 373 }
 374
 375 /* VFS operations structure */
 376
 377 static struct vfs_fn_pointers posixacl_fns = {
 378         .sys_acl_get_fd_fn = posixacl_sys_acl_get_fd,
 379         .sys_acl_blob_get_fd_fn = posix_sys_acl_blob_get_fd,
 380         .sys_acl_set_fd_fn = posixacl_sys_acl_set_fd,
 381         .sys_acl_delete_def_fd_fn = posixacl_sys_acl_delete_def_fd,
 382 };
 383
 384 static_decl_vfs;
 385 NTSTATUS vfs_posixacl_init(TALLOC_CTX *ctx)
 386 {
 387         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "posixacl",
 388                                 &posixacl_fns);
 389 }