path: root/source3/smbd/close.c

/*
   Unix SMB/CIFS implementation.
   file closing
   Copyright (C) Andrew Tridgell 1992-1998
   Copyright (C) Jeremy Allison 1992-2007.
   Copyright (C) Volker Lendecke 2005

   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"
#include "system/filesys.h"
#include "lib/util/server_id.h"
#include "printing.h"
#include "locking/share_mode_lock.h"
#include "smbd/smbd.h"
#include "smbd/globals.h"
#include "smbd/smbXsrv_open.h"
#include "smbd/scavenger.h"
#include "fake_file.h"
#include "transfer_file.h"
#include "auth.h"
#include "messages.h"
#include "librpc/gen_ndr/ndr_open_files.h"
#include "lib/util/tevent_ntstatus.h"
#include "source3/smbd/dir.h"

/****************************************************************************
 Run a file if it is a magic script.
****************************************************************************/

static NTSTATUS check_magic(struct files_struct *fsp)
{
	int ret;
	const struct loadparm_substitution *lp_sub =
		loadparm_s3_global_substitution();
	const char *magic_output = NULL;
	SMB_STRUCT_STAT st;
	int tmp_fd, outfd;
	TALLOC_CTX *ctx = NULL;
	const char *p;
	struct connection_struct *conn = fsp->conn;
	char *fname = NULL;
	NTSTATUS status;

	if (!*lp_magic_script(talloc_tos(), lp_sub, SNUM(conn))) {
		return NT_STATUS_OK;
	}

	DEBUG(5,("checking magic for %s\n", fsp_str_dbg(fsp)));

	ctx = talloc_stackframe();

	fname = fsp->fsp_name->base_name;

	if (!(p = strrchr_m(fname,'/'))) {
		p = fname;
	} else {
		p++;
	}

	if (!strequal(lp_magic_script(talloc_tos(), lp_sub, SNUM(conn)),p)) {
		status = NT_STATUS_OK;
		goto out;
	}

	if (*lp_magic_output(talloc_tos(), lp_sub, SNUM(conn))) {
		magic_output = lp_magic_output(talloc_tos(), lp_sub, SNUM(conn));
	} else {
		magic_output = talloc_asprintf(ctx,
				"%s.out",
				fname);
	}
	if (!magic_output) {
		status = NT_STATUS_NO_MEMORY;
		goto out;
	}

	/* Ensure we don't depend on user's PATH. */
	p = talloc_asprintf(ctx, "./%s", fname);
	if (!p) {
		status = NT_STATUS_NO_MEMORY;
		goto out;
	}

	if (chmod(fname, 0755) == -1) {
		status = map_nt_error_from_unix(errno);
		goto out;
	}
	ret = smbrun(p, &tmp_fd, NULL);
	DEBUG(3,("Invoking magic command %s gave %d\n",
		p,ret));

	unlink(fname);
	if (ret != 0 || tmp_fd == -1) {
		if (tmp_fd != -1) {
			close(tmp_fd);
		}
		status = NT_STATUS_UNSUCCESSFUL;
		goto out;
	}
	outfd = open(magic_output, O_CREAT|O_EXCL|O_RDWR, 0600);
	if (outfd == -1) {
		int err = errno;
		close(tmp_fd);
		status = map_nt_error_from_unix(err);
		goto out;
	}

	if (sys_fstat(tmp_fd, &st, false) == -1) {
		int err = errno;
		close(tmp_fd);
		close(outfd);
		status = map_nt_error_from_unix(err);
		goto out;
	}

	if (transfer_file(tmp_fd,outfd,(off_t)st.st_ex_size) == (off_t)-1) {
		int err = errno;
		close(tmp_fd);
		close(outfd);
		status = map_nt_error_from_unix(err);
		goto out;
	}
	close(tmp_fd);
	if (close(outfd) == -1) {
		status = map_nt_error_from_unix(errno);
		goto out;
	}

	status = NT_STATUS_OK;

 out:
	TALLOC_FREE(ctx);
	return status;
}

/****************************************************************************
 Delete all streams
****************************************************************************/

NTSTATUS delete_all_streams(struct files_struct *fsp,
			    struct files_struct *dirfsp,
			    struct smb_filename *fsp_atname)
{
	struct smb_filename *smb_fname = fsp->fsp_name;
	struct stream_struct *stream_info = NULL;
	unsigned int i;
	unsigned int num_streams = 0;
	TALLOC_CTX *frame = talloc_stackframe();
	NTSTATUS status;

	status = vfs_fstreaminfo(fsp,
				 talloc_tos(),
				 &num_streams,
				 &stream_info);

	if (NT_STATUS_EQUAL(status, NT_STATUS_NOT_IMPLEMENTED)) {
		DEBUG(10, ("no streams around\n"));
		TALLOC_FREE(frame);
		return NT_STATUS_OK;
	}

	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(10, ("vfs_fstreaminfo failed: %s\n",
			   nt_errstr(status)));
		goto fail;
	}

	DEBUG(10, ("delete_all_streams found %d streams\n",
		   num_streams));

	if (num_streams == 0) {
		TALLOC_FREE(frame);
		return NT_STATUS_OK;
	}

	for (i=0; i<num_streams; i++) {
		int res;
		struct smb_filename *smb_fname_stream;

		if (strequal(stream_info[i].name, "::$DATA")) {
			continue;
		}

		smb_fname_stream = synthetic_smb_fname(
			talloc_tos(),
			fsp_atname->base_name,
			stream_info[i].name,
			NULL,
			smb_fname->twrp,
			(smb_fname->flags & ~SMB_FILENAME_POSIX_PATH));
		if (smb_fname_stream == NULL) {
			DEBUG(0, ("talloc_aprintf failed\n"));
			status = NT_STATUS_NO_MEMORY;
			goto fail;
		}

		res = SMB_VFS_UNLINKAT(dirfsp->conn,
				       dirfsp,
				       smb_fname_stream,
				       0);

		if (res == -1) {
			status = map_nt_error_from_unix(errno);
			DEBUG(10, ("Could not delete stream %s: %s\n",
				   smb_fname_str_dbg(smb_fname_stream),
				   strerror(errno)));
			TALLOC_FREE(smb_fname_stream);
			break;
		}
		TALLOC_FREE(smb_fname_stream);
	}

 fail:
	TALLOC_FREE(frame);
	return status;
}

struct has_other_nonposix_opens_state {
	files_struct *fsp;
	bool found_another;
};

static bool has_other_nonposix_opens_fn(
	struct share_mode_entry *e,
	bool *modified,
	void *private_data)
{
	struct has_other_nonposix_opens_state *state = private_data;
	struct files_struct *fsp = state->fsp;

	if (e->flags & SHARE_ENTRY_FLAG_POSIX_OPEN) {
		return false;
	}
	if (fsp != NULL) {
		if (e->name_hash != fsp->name_hash) {
			return false;
		}
		if (e->share_file_id == fh_get_gen_id(fsp->fh)) {
			struct server_id self = messaging_server_id(
				fsp->conn->sconn->msg_ctx);
			if (server_id_equal(&self, &e->pid)) {
				return false;
			}
		}
	}
	if (share_entry_stale_pid(e)) {
		return false;
	}

	state->found_another = true;
	return true;
}

bool has_other_nonposix_opens(struct share_mode_lock *lck,
			      struct files_struct *fsp)
{
	struct has_other_nonposix_opens_state state = { .fsp = fsp };
	bool ok;

	ok = share_mode_forall_entries(
		lck, has_other_nonposix_opens_fn, &state);
	if (!ok) {
		return false;
	}
	return state.found_another;
}

struct has_delete_access_opens_state {
	bool delete_access;
	bool delete_pending;
};

static bool has_delete_access_opens_fn(
	struct share_mode_entry *e,
	bool *modified,
	void *private_data)
{
	struct has_delete_access_opens_state *state = private_data;

	if (share_entry_stale_pid(e)) {
		return false;
	}

	if (e->access_mask & SEC_STD_DELETE) {
		state->delete_access = true;
	}
	return false;
}

bool has_delete_opens(struct files_struct *fsp,
		      struct share_mode_lock *lck,
		      bool *delete_access,
		      bool *delete_pending)
{
	struct has_delete_access_opens_state state = {};
	bool ok;

	ok = share_mode_forall_entries(
		lck, has_delete_access_opens_fn, &state);
	if (!ok) {
		return false;
	}

	*delete_access = state.delete_access;
	*delete_pending = is_delete_on_close_set(lck, fsp->name_hash);
	return true;
}

bool has_nonposix_opens(struct share_mode_lock *lck)
{
	struct has_other_nonposix_opens_state state = {};
	bool ok;

	ok = share_mode_forall_entries(
		lck, has_other_nonposix_opens_fn, &state);
	if (!ok) {
		return false;
	}
	return state.found_another;
}

struct close_share_mode_lock_state {
	struct share_mode_entry_prepare_state prepare_state;
	const char *object_type;
	struct files_struct *fsp