--- /dev/null
+/*
+ Unix SMB/CIFS implementation.
+ Check access to files based on security descriptors.
+ Copyright (C) Jeremy Allison 2005-2006.
+ Copyright (C) Michael Adam 2007.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+
+extern struct current_user current_user;
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_ACLS
+
+/****************************************************************************
+ Helper function that gets a security descriptor by connection and
+ file name.
+ NOTE: This is transitional, in the sense that SMB_VFS_GET_NT_ACL really
+ should *not* get a files_struct pointer but a connection_struct ptr
+ (automatic by the vfs handle) and the file name and _use_ that!
+****************************************************************************/
+static NTSTATUS conn_get_nt_acl(TALLOC_CTX *mem_ctx,
+ struct connection_struct *conn,
+ const char *fname,
+ SMB_STRUCT_STAT *psbuf,
+ struct security_descriptor **psd)
+{
+ NTSTATUS status;
+ struct files_struct *fsp = NULL;
+ struct security_descriptor *secdesc = NULL;
+ size_t secdesc_size;
+
+ if (!VALID_STAT(*psbuf)) {
+ if (SMB_VFS_STAT(conn, fname, psbuf) != 0) {
+ return map_nt_error_from_unix(errno);
+ }
+ }
+
+ /* fake a files_struct ptr: */
+
+ status = open_file_stat(conn, NULL, fname, psbuf, &fsp);
+ /* Perhaps it is a directory */
+ if (NT_STATUS_EQUAL(status, NT_STATUS_FILE_IS_A_DIRECTORY)) {
+ status = open_directory(conn, NULL, fname, psbuf,
+ READ_CONTROL_ACCESS,
+ FILE_SHARE_READ|FILE_SHARE_WRITE,
+ FILE_OPEN,
+ 0,
+ FILE_ATTRIBUTE_DIRECTORY,
+ NULL, &fsp);
+ }
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(3, ("Unable to open file %s: %s\n", fname,
+ nt_errstr(status)));
+ return status;
+ }
+
+ secdesc_size = SMB_VFS_GET_NT_ACL(fsp, fname,
+ (OWNER_SECURITY_INFORMATION |
+ GROUP_SECURITY_INFORMATION |
+ DACL_SECURITY_INFORMATION),
+ &secdesc);
+ if (secdesc_size == 0) {
+ DEBUG(5, ("Unable to get NT ACL for file %s\n", fname));
+ return NT_STATUS_ACCESS_DENIED;
+ }
+
+ *psd = talloc_move(mem_ctx, &secdesc);
+ close_file(fsp, NORMAL_CLOSE);
+ return NT_STATUS_OK;
+}
+
+static bool can_access_file_acl(struct connection_struct *conn,
+ const char * fname, SMB_STRUCT_STAT *psbuf,
+ uint32_t access_mask)
+{
+ bool result;
+ NTSTATUS status;
+ uint32_t access_granted;
+ struct security_descriptor *secdesc = NULL;
+
+ status = conn_get_nt_acl(talloc_tos(), conn, fname, psbuf, &secdesc);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(5, ("Could not get acl: %s\n", nt_errstr(status)));
+ return false;
+ }
+
+ result = se_access_check(secdesc, current_user.nt_user_token,
+ access_mask, &access_granted, &status);
+ TALLOC_FREE(secdesc);
+ return result;
+}
+
+/****************************************************************************
+ Actually emulate the in-kernel access checking for delete access. We need
+ this to successfully return ACCESS_DENIED on a file open for delete access.
+****************************************************************************/
+
+bool can_delete_file_in_directory(connection_struct *conn, const char *fname)
+{
+ SMB_STRUCT_STAT sbuf;
+ TALLOC_CTX *ctx = talloc_tos();
+ char *dname = NULL;
+
+ if (!CAN_WRITE(conn)) {
+ return False;
+ }
+
+ /* Get the parent directory permission mask and owners. */
+ if (!parent_dirname_talloc(ctx,
+ fname,
+ &dname,
+ NULL)) {
+ return False;
+ }
+ if(SMB_VFS_STAT(conn, dname, &sbuf) != 0) {
+ return False;
+ }
+
+ /* fast paths first */
+
+ if (!S_ISDIR(sbuf.st_mode)) {
+ return False;
+ }
+ if (current_user.ut.uid == 0 || conn->admin_user) {
+ /* I'm sorry sir, I didn't know you were root... */
+ return True;
+ }
+
+ /* Check primary owner write access. */
+ if (current_user.ut.uid == sbuf.st_uid) {
+ return (sbuf.st_mode & S_IWUSR) ? True : False;
+ }
+
+#ifdef S_ISVTX
+ /* sticky bit means delete only by owner or root. */
+ if (sbuf.st_mode & S_ISVTX) {
+ SMB_STRUCT_STAT sbuf_file;
+ if(SMB_VFS_STAT(conn, fname, &sbuf_file) != 0) {
+ if (errno == ENOENT) {
+ /* If the file doesn't already exist then
+ * yes we'll be able to delete it. */
+ return True;
+ }
+ return False;
+ }
+ /*
+ * Patch from SATOH Fumiyasu <fumiyas@miraclelinux.com>
+ * for bug #3348. Don't assume owning sticky bit
+ * directory means write access allowed.
+ */
+ if (current_user.ut.uid != sbuf_file.st_uid) {
+ return False;
+ }
+ }
+#endif
+
+ /* now for ACL checks */
+
+ return can_access_file_acl(conn, dname, &sbuf, FILE_WRITE_DATA);
+}
+
+/****************************************************************************
+ Actually emulate the in-kernel access checking for read/write access. We need
+ this to successfully check for ability to write for dos filetimes.
+ Note this doesn't take into account share write permissions.
+****************************************************************************/
+
+bool can_access_file(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf, uint32 access_mask)
+{
+ if (!(access_mask & (FILE_READ_DATA|FILE_WRITE_DATA))) {
+ return False;
+ }
+ access_mask &= (FILE_READ_DATA|FILE_WRITE_DATA);
+
+ /* some fast paths first */
+
+ DEBUG(10,("can_access_file: requesting 0x%x on file %s\n",
+ (unsigned int)access_mask, fname ));
+
+ if (current_user.ut.uid == 0 || conn->admin_user) {
+ /* I'm sorry sir, I didn't know you were root... */
+ return True;
+ }
+
+ if (!VALID_STAT(*psbuf)) {
+ /* Get the file permission mask and owners. */
+ if(SMB_VFS_STAT(conn, fname, psbuf) != 0) {
+ return False;
+ }
+ }
+
+ /* Check primary owner access. */
+ if (current_user.ut.uid == psbuf->st_uid) {
+ switch (access_mask) {
+ case FILE_READ_DATA:
+ return (psbuf->st_mode & S_IRUSR) ? True : False;
+
+ case FILE_WRITE_DATA:
+ return (psbuf->st_mode & S_IWUSR) ? True : False;
+
+ default: /* FILE_READ_DATA|FILE_WRITE_DATA */
+
+ if ((psbuf->st_mode & (S_IWUSR|S_IRUSR)) == (S_IWUSR|S_IRUSR)) {
+ return True;
+ } else {
+ return False;
+ }
+ }
+ }
+
+ /* now for ACL checks */
+
+ return can_access_file_acl(conn, fname, psbuf, access_mask);
+}
+
+/****************************************************************************
+ Userspace check for write access.
+ Note this doesn't take into account share write permissions.
+****************************************************************************/
+
+bool can_write_to_file(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf)
+{
+ return can_access_file(conn, fname, psbuf, FILE_WRITE_DATA);
+}
+
return True;
}
-/****************************************************************************
- Helper function that gets a security descriptor by connection and
- file name.
- NOTE: This is transitional, in the sense that SMB_VFS_GET_NT_ACL really
- should *not* get a files_struct pointer but a connection_struct ptr
- (automatic by the vfs handle) and the file name and _use_ that!
-****************************************************************************/
-static NTSTATUS conn_get_nt_acl(TALLOC_CTX *mem_ctx,
- struct connection_struct *conn,
- const char *fname,
- SMB_STRUCT_STAT *psbuf,
- struct security_descriptor **psd)
-{
- NTSTATUS status;
- struct files_struct *fsp = NULL;
- struct security_descriptor *secdesc = NULL;
- size_t secdesc_size;
-
- if (!VALID_STAT(*psbuf)) {
- if (SMB_VFS_STAT(conn, fname, psbuf) != 0) {
- return map_nt_error_from_unix(errno);
- }
- }
-
- /* fake a files_struct ptr: */
-
- status = open_file_stat(conn, NULL, fname, psbuf, &fsp);
- /* Perhaps it is a directory */
- if (NT_STATUS_EQUAL(status, NT_STATUS_FILE_IS_A_DIRECTORY)) {
- status = open_directory(conn, NULL, fname, psbuf,
- READ_CONTROL_ACCESS,
- FILE_SHARE_READ|FILE_SHARE_WRITE,
- FILE_OPEN,
- 0,
- FILE_ATTRIBUTE_DIRECTORY,
- NULL, &fsp);
- }
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(3, ("Unable to open file %s: %s\n", fname,
- nt_errstr(status)));
- return status;
- }
-
- secdesc_size = SMB_VFS_GET_NT_ACL(fsp, fname,
- (OWNER_SECURITY_INFORMATION |
- GROUP_SECURITY_INFORMATION |
- DACL_SECURITY_INFORMATION),
- &secdesc);
- if (secdesc_size == 0) {
- DEBUG(5, ("Unable to get NT ACL for file %s\n", fname));
- return NT_STATUS_ACCESS_DENIED;
- }
-
- *psd = talloc_move(mem_ctx, &secdesc);
- close_file(fsp, NORMAL_CLOSE);
- return NT_STATUS_OK;
-}
-
-static bool can_access_file_acl(struct connection_struct *conn,
- const char * fname, SMB_STRUCT_STAT *psbuf,
- uint32_t access_mask)
-{
- bool result;
- NTSTATUS status;
- uint32_t access_granted;
- struct security_descriptor *secdesc = NULL;
-
- status = conn_get_nt_acl(talloc_tos(), conn, fname, psbuf, &secdesc);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(5, ("Could not get acl: %s\n", nt_errstr(status)));
- return false;
- }
-
- result = se_access_check(secdesc, current_user.nt_user_token,
- access_mask, &access_granted, &status);
- TALLOC_FREE(secdesc);
- return result;
-}
-
-/****************************************************************************
- Actually emulate the in-kernel access checking for delete access. We need
- this to successfully return ACCESS_DENIED on a file open for delete access.
-****************************************************************************/
-
-bool can_delete_file_in_directory(connection_struct *conn, const char *fname)
-{
- SMB_STRUCT_STAT sbuf;
- TALLOC_CTX *ctx = talloc_tos();
- char *dname = NULL;
-
- if (!CAN_WRITE(conn)) {
- return False;
- }
-
- /* Get the parent directory permission mask and owners. */
- if (!parent_dirname_talloc(ctx,
- fname,
- &dname,
- NULL)) {
- return False;
- }
- if(SMB_VFS_STAT(conn, dname, &sbuf) != 0) {
- return False;
- }
-
- /* fast paths first */
-
- if (!S_ISDIR(sbuf.st_mode)) {
- return False;
- }
- if (current_user.ut.uid == 0 || conn->admin_user) {
- /* I'm sorry sir, I didn't know you were root... */
- return True;
- }
-
- /* Check primary owner write access. */
- if (current_user.ut.uid == sbuf.st_uid) {
- return (sbuf.st_mode & S_IWUSR) ? True : False;
- }
-
-#ifdef S_ISVTX
- /* sticky bit means delete only by owner or root. */
- if (sbuf.st_mode & S_ISVTX) {
- SMB_STRUCT_STAT sbuf_file;
- if(SMB_VFS_STAT(conn, fname, &sbuf_file) != 0) {
- if (errno == ENOENT) {
- /* If the file doesn't already exist then
- * yes we'll be able to delete it. */
- return True;
- }
- return False;
- }
- /*
- * Patch from SATOH Fumiyasu <fumiyas@miraclelinux.com>
- * for bug #3348. Don't assume owning sticky bit
- * directory means write access allowed.
- */
- if (current_user.ut.uid != sbuf_file.st_uid) {
- return False;
- }
- }
-#endif
-
- /* now for ACL checks */
-
- return can_access_file_acl(conn, dname, &sbuf, FILE_WRITE_DATA);
-}
-
-/****************************************************************************
- Actually emulate the in-kernel access checking for read/write access. We need
- this to successfully check for ability to write for dos filetimes.
- Note this doesn't take into account share write permissions.
-****************************************************************************/
-
-bool can_access_file(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf, uint32 access_mask)
-{
- if (!(access_mask & (FILE_READ_DATA|FILE_WRITE_DATA))) {
- return False;
- }
- access_mask &= (FILE_READ_DATA|FILE_WRITE_DATA);
-
- /* some fast paths first */
-
- DEBUG(10,("can_access_file: requesting 0x%x on file %s\n",
- (unsigned int)access_mask, fname ));
-
- if (current_user.ut.uid == 0 || conn->admin_user) {
- /* I'm sorry sir, I didn't know you were root... */
- return True;
- }
-
- if (!VALID_STAT(*psbuf)) {
- /* Get the file permission mask and owners. */
- if(SMB_VFS_STAT(conn, fname, psbuf) != 0) {
- return False;
- }
- }
-
- /* Check primary owner access. */
- if (current_user.ut.uid == psbuf->st_uid) {
- switch (access_mask) {
- case FILE_READ_DATA:
- return (psbuf->st_mode & S_IRUSR) ? True : False;
-
- case FILE_WRITE_DATA:
- return (psbuf->st_mode & S_IWUSR) ? True : False;
-
- default: /* FILE_READ_DATA|FILE_WRITE_DATA */
-
- if ((psbuf->st_mode & (S_IWUSR|S_IRUSR)) == (S_IWUSR|S_IRUSR)) {
- return True;
- } else {
- return False;
- }
- }
- }
-
- /* now for ACL checks */
-
- return can_access_file_acl(conn, fname, psbuf, access_mask);
-}
-
-/****************************************************************************
- Userspace check for write access.
- Note this doesn't take into account share write permissions.
-****************************************************************************/
-
-bool can_write_to_file(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf)
-{
- return can_access_file(conn, fname, psbuf, FILE_WRITE_DATA);
-}
-
/********************************************************************
Pull the NT ACL from a file on disk or the OpenEventlog() access
check. Caller is responsible for freeing the returned security
git.samba.org / obnox / samba / samba-obnox.git / commitdiff