Adding upstream version 2:4.20.0+dfsg.upstream/2%4.20.0+dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2651 insertions, 0 deletions

diff --git a/source3/smbd/files.c b/source3/smbd/files.c
new file mode 100644
index 0000000..6aad76a
--- /dev/null
+++ b/source3/smbd/files.c
@@ -0,0 +1,2651 @@
+/*
+   Unix SMB/CIFS implementation.
+   Files[] structure handling
+   Copyright (C) Andrew Tridgell 1998
+
+   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 "smbd/smbd.h"
+#include "smbd/globals.h"
+#include "smbd/smbXsrv_open.h"
+#include "libcli/security/security.h"
+#include "util_tdb.h"
+#include "lib/util/bitmap.h"
+#include "lib/util/strv.h"
+#include "lib/util/memcache.h"
+#include "libcli/smb/reparse.h"
+
+#define FILE_HANDLE_OFFSET 0x1000
+
+static NTSTATUS fsp_attach_smb_fname(struct files_struct *fsp,
+				     struct smb_filename **_smb_fname);
+
+/**
+ * create new fsp to be used for file_new or a durable handle reconnect
+ */
+NTSTATUS fsp_new(struct connection_struct *conn, TALLOC_CTX *mem_ctx,
+		 files_struct **result)
+{
+	NTSTATUS status = NT_STATUS_NO_MEMORY;
+	files_struct *fsp = NULL;
+	struct smbd_server_connection *sconn = conn->sconn;
+
+	fsp = talloc_zero(mem_ctx, struct files_struct);
+	if (fsp == NULL) {
+		goto fail;
+	}
+
+	/*
+	 * This can't be a child of fsp because the file_handle can be ref'd
+	 * when doing a dos/fcb open, which will then share the file_handle
+	 * across multiple fsps.
+	 */
+	fsp->fh = fd_handle_create(mem_ctx);
+	if (fsp->fh == NULL) {
+		goto fail;
+	}
+
+	fsp->fsp_flags.use_ofd_locks = !lp_smbd_force_process_locks(SNUM(conn));
+#ifndef HAVE_OFD_LOCKS
+	fsp->fsp_flags.use_ofd_locks = false;
+#endif
+
+	fh_set_refcount(fsp->fh, 1);
+	fsp_set_fd(fsp, -1);
+
+	fsp->fnum = FNUM_FIELD_INVALID;
+	fsp->conn = conn;
+	fsp->close_write_time = make_omit_timespec();
+
+	DLIST_ADD(sconn->files, fsp);
+	sconn->num_files += 1;
+
+	conn->num_files_open++;
+
+	DBG_INFO("allocated files structure (%u used)\n",
+		(unsigned int)sconn->num_files);
+
+	*result = fsp;
+	return NT_STATUS_OK;
+
+fail:
+	if (fsp != NULL) {
+		TALLOC_FREE(fsp->fh);
+	}
+	TALLOC_FREE(fsp);
+
+	return status;
+}
+
+void fsp_set_gen_id(files_struct *fsp)
+{
+	static uint64_t gen_id = 1;
+
+	/*
+	 * A billion of 64-bit increments per second gives us
+	 * more than 500 years of runtime without wrap.
+	 */
+	gen_id++;
+	fh_set_gen_id(fsp->fh, gen_id);
+}
+
+/****************************************************************************
+ Find first available file slot.
+****************************************************************************/
+
+NTSTATUS fsp_bind_smb(struct files_struct *fsp, struct smb_request *req)
+{
+	struct smbXsrv_open *op = NULL;
+	NTTIME now;
+	NTSTATUS status;
+
+	if (req == NULL) {
+		DBG_DEBUG("INTERNAL_OPEN_ONLY, skipping smbXsrv_open\n");
+		return NT_STATUS_OK;
+	}
+
+	now = timeval_to_nttime(&fsp->open_time);
+
+	status = smbXsrv_open_create(req->xconn,
+				     fsp->conn->session_info,
+				     now,
+				     &op);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+	fsp->op = op;
+	op->compat = fsp;
+	fsp->fnum = op->local_id;
+
+	fsp->mid = req->mid;
+	req->chain_fsp = fsp;
+
+	DBG_DEBUG("fsp [%s] mid [%" PRIu64"]\n",
+		fsp_str_dbg(fsp), fsp->mid);
+
+	return NT_STATUS_OK;
+}
+
+NTSTATUS file_new(struct smb_request *req, connection_struct *conn,
+		  files_struct **result)
+{
+	struct smbd_server_connection *sconn = conn->sconn;
+	files_struct *fsp;
+	NTSTATUS status;
+
+	status = fsp_new(conn, conn, &fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	GetTimeOfDay(&fsp->open_time);
+
+	status = fsp_bind_smb(fsp, req);
+	if (!NT_STATUS_IS_OK(status)) {
+		file_free(NULL, fsp);
+		return status;
+	}
+
+	fsp_set_gen_id(fsp);
+
+	/*
+	 * Create an smb_filename with "" for the base_name.  There are very
+	 * few NULL checks, so make sure it's initialized with something. to
+	 * be safe until an audit can be done.
+	 */
+	fsp->fsp_name = synthetic_smb_fname(fsp,
+					    "",
+					    NULL,
+					    NULL,
+					    0,
+					    0);
+	if (fsp->fsp_name == NULL) {
+		file_free(NULL, fsp);
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	DBG_INFO("new file %s\n", fsp_fnum_dbg(fsp));
+
+	/* A new fsp invalidates the positive and
+	  negative fsp_fi_cache as the new fsp is pushed
+	  at the start of the list and we search from
+	  a cache hit to the *end* of the list. */
+
+	ZERO_STRUCT(sconn->fsp_fi_cache);
+
+	*result = fsp;
+	return NT_STATUS_OK;
+}
+
+NTSTATUS create_internal_fsp(connection_struct *conn,
+			     const struct smb_filename *smb_fname,
+			     struct files_struct **_fsp)
+{
+	struct files_struct *fsp = NULL;
+	NTSTATUS status;
+
+	status = file_new(NULL, conn, &fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	status = fsp_set_smb_fname(fsp, smb_fname);
+	if (!NT_STATUS_IS_OK(status)) {
+		file_free(NULL, fsp);
+		return status;
+	}
+
+	*_fsp = fsp;
+	return NT_STATUS_OK;
+}
+
+/*
+ * Create an internal fsp for an *existing* directory.
+ *
+ * This should only be used by callers in the VFS that need to control the
+ * opening of the directory. Otherwise use open_internal_dirfsp().
+ */
+NTSTATUS create_internal_dirfsp(connection_struct *conn,
+				const struct smb_filename *smb_dname,
+				struct files_struct **_fsp)
+{
+	struct files_struct *fsp = NULL;
+	NTSTATUS status;
+
+	status = create_internal_fsp(conn, smb_dname, &fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	fsp->access_mask = FILE_LIST_DIRECTORY;
+	fsp->fsp_flags.is_directory = true;
+	fsp->fsp_flags.is_dirfsp = true;
+
+	*_fsp = fsp;
+	return NT_STATUS_OK;
+}
+
+/*
+ * Open an internal fsp for an *existing* directory.
+ */
+NTSTATUS open_internal_dirfsp(connection_struct *conn,
+			      const struct smb_filename *smb_dname,
+			      int _open_flags,
+			      struct files_struct **_fsp)
+{
+	struct vfs_open_how how = { .flags = _open_flags, };
+	struct files_struct *fsp = NULL;
+	NTSTATUS status;
+
+	status = create_internal_dirfsp(conn, smb_dname, &fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+#ifdef O_DIRECTORY
+	how.flags |= O_DIRECTORY;
+#endif
+	status = fd_openat(conn->cwd_fsp, fsp->fsp_name, fsp, &how);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_INFO("Could not open fd for %s (%s)\n",
+			 smb_fname_str_dbg(smb_dname),
+			 nt_errstr(status));
+		file_free(NULL, fsp);
+		return status;
+	}
+
+	status = vfs_stat_fsp(fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		file_free(NULL, fsp);
+		return status;
+	}
+
+	if (!S_ISDIR(fsp->fsp_name->st.st_ex_mode)) {
+		DBG_ERR("%s is not a directory!\n",
+			smb_fname_str_dbg(smb_dname));
+                file_free(NULL, fsp);
+		return NT_STATUS_NOT_A_DIRECTORY;
+	}
+
+	fsp->file_id = vfs_file_id_from_sbuf(conn, &fsp->fsp_name->st);
+
+	*_fsp = fsp;
+	return NT_STATUS_OK;
+}
+
+/*
+ * Convert a pathref dirfsp into a real fsp. No need to do any cwd
+ * tricks, we just open ".".
+ */
+NTSTATUS openat_internal_dir_from_pathref(
+	struct files_struct *dirfsp,
+	int _open_flags,
+	struct files_struct **_fsp)
+{
+	struct connection_struct *conn = dirfsp->conn;
+	struct smb_filename *smb_dname = dirfsp->fsp_name;
+	struct files_struct *fsp = NULL;
+	char dot[] = ".";
+	struct smb_filename smb_dot = {
+		.base_name = dot,
+		.flags = smb_dname->flags,
+		.twrp = smb_dname->twrp,
+	};
+	struct vfs_open_how how = { .flags = _open_flags, };
+	NTSTATUS status;
+
+	status = create_internal_dirfsp(conn, smb_dname, &fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	/*
+	 * Pointless for opening ".", but you never know...
+	 */
+	how.flags |= O_NOFOLLOW;
+
+	status = fd_openat(dirfsp, &smb_dot, fsp, &how);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_INFO("fd_openat(\"%s\", \".\") failed: %s\n",
+			 fsp_str_dbg(dirfsp),
+			 nt_errstr(status));
+		file_free(NULL, fsp);
+		return status;
+	}
+
+	fsp->fsp_name->st = smb_dname->st;
+	fsp->file_id = vfs_file_id_from_sbuf(conn, &fsp->fsp_name->st);
+	*_fsp = fsp;
+	return NT_STATUS_OK;
+}
+
+/*
+ * The "link" in the name doesn't imply link in the filesystem
+ * sense. It's a object that "links" together an fsp and an smb_fname
+ * and the link allocated as talloc child of an fsp.
+ *
+ * The link is created for fsps that openat_pathref_fsp() returns in
+ * smb_fname->fsp. When this fsp is freed by file_free() by some caller
+ * somewhere, the destructor fsp_smb_fname_link_destructor() on the link object
+ * will use the link to reset the reference in smb_fname->fsp that is about to
+ * go away.
+ *
+ * This prevents smb_fname_internal_fsp_destructor() from seeing dangling fsp
+ * pointers.
+ */
+
+struct fsp_smb_fname_link {
+	struct fsp_smb_fname_link **smb_fname_link;
+	struct files_struct **smb_fname_fsp;
+};
+
+static int fsp_smb_fname_link_destructor(struct fsp_smb_fname_link *link)
+{
+	if (link->smb_fname_link == NULL) {
+		return 0;
+	}
+
+	*link->smb_fname_link = NULL;
+	*link->smb_fname_fsp = NULL;
+	return 0;
+}
+
+static NTSTATUS fsp_smb_fname_link(struct files_struct *fsp,
+				   struct fsp_smb_fname_link **smb_fname_link,
+				   struct files_struct **smb_fname_fsp)
+{
+	struct fsp_smb_fname_link *link = NULL;
+
+	SMB_ASSERT(*smb_fname_link == NULL);
+	SMB_ASSERT(*smb_fname_fsp == NULL);
+
+	link = talloc_zero(fsp, struct fsp_smb_fname_link);
+	if (link == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	link->smb_fname_link = smb_fname_link;
+	link->smb_fname_fsp = smb_fname_fsp;
+	*smb_fname_link = link;
+	*smb_fname_fsp = fsp;
+
+	talloc_set_destructor(link, fsp_smb_fname_link_destructor);
+	return NT_STATUS_OK;
+}
+
+/*
+ * Free a link, carefully avoiding to trigger the link destructor
+ */
+static void destroy_fsp_smb_fname_link(struct fsp_smb_fname_link **_link)
+{
+	struct fsp_smb_fname_link *link = *_link;
+
+	if (link == NULL) {
+		return;
+	}
+	talloc_set_destructor(link, NULL);
+	TALLOC_FREE(link);
+	*_link = NULL;
+}
+
+/*
+ * Talloc destructor set on an smb_fname set by openat_pathref_fsp() used to
+ * close the embedded smb_fname->fsp.
+ */
+static int smb_fname_fsp_destructor(struct smb_filename *smb_fname)
+{
+	struct files_struct *fsp = smb_fname->fsp;
+	struct files_struct *base_fsp = NULL;
+	NTSTATUS status;
+	int saved_errno = errno;
+
+	destroy_fsp_smb_fname_link(&smb_fname->fsp_link);
+
+	if (fsp == NULL) {
+		errno = saved_errno;
+		return 0;
+	}
+
+	if (fsp_is_alternate_stream(fsp)) {
+		base_fsp = fsp->base_fsp;
+	}
+
+	status = fd_close(fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_ERR("Closing fd for fsp [%s] failed: %s. "
+			"Please check your filesystem!!!\n",
+			fsp_str_dbg(fsp), nt_errstr(status));
+	}
+	file_free(NULL, fsp);
+	smb_fname->fsp = NULL;
+
+	if (base_fsp != NULL) {
+		base_fsp->stream_fsp = NULL;
+		status = fd_close(base_fsp);
+		if (!NT_STATUS_IS_OK(status)) {
+			DBG_ERR("Closing fd for base_fsp [%s] failed: %s. "
+				"Please check your filesystem!!!\n",
+				fsp_str_dbg(base_fsp), nt_errstr(status));
+		}
+		file_free(NULL, base_fsp);
+	}
+
+	errno = saved_errno;
+	return 0;
+}
+
+static NTSTATUS openat_pathref_fullname(
+	struct connection_struct *conn,
+	const struct files_struct *dirfsp,
+	struct files_struct *basefsp,
+	struct smb_filename **full_fname,
+	struct smb_filename *smb_fname,
+	const struct vfs_open_how *how)
+{
+	struct files_struct *fsp = NULL;
+	bool have_dirfsp = (dirfsp != NULL);
+	bool have_basefsp = (basefsp != NULL);
+	NTSTATUS status;
+
+	DBG_DEBUG("smb_fname [%s]\n", smb_fname_str_dbg(smb_fname));
+
+	SMB_ASSERT(smb_fname->fsp == NULL);
+	SMB_ASSERT(have_dirfsp != have_basefsp);
+
+	status = fsp_new(conn, conn, &fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	GetTimeOfDay(&fsp->open_time);
+	fsp_set_gen_id(fsp);
+	ZERO_STRUCT(conn->sconn->fsp_fi_cache);
+
+	fsp->fsp_flags.is_pathref = true;
+
+	status = fsp_attach_smb_fname(fsp, full_fname);
+	if (!NT_STATUS_IS_OK(status)) {
+		goto fail;
+	}
+	fsp_set_base_fsp(fsp, basefsp);
+
+	status = fd_openat(dirfsp, smb_fname, fsp, how);
+	if (!NT_STATUS_IS_OK(status)) {
+
+		smb_fname->st = fsp->fsp_name->st;
+
+		if (NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND) ||
+		    NT_STATUS_EQUAL(status, NT_STATUS_OBJECT_PATH_NOT_FOUND) ||
+		    NT_STATUS_EQUAL(status, NT_STATUS_STOPPED_ON_SYMLINK))
+		{
+			/*
+			 * streams_xattr return NT_STATUS_NOT_FOUND for
+			 * opens of not yet existing streams.
+			 *
+			 * ELOOP maps to NT_STATUS_OBJECT_PATH_NOT_FOUND
+			 * and this will result from a open request from
+			 * a POSIX client on a symlink.
+			 *
+			 * NT_STATUS_OBJECT_NAME_NOT_FOUND is the simple
+			 * ENOENT case.
+			 *
+			 * NT_STATUS_STOPPED_ON_SYMLINK is returned when trying
+			 * to open a symlink, our callers are not interested in
+			 * this.
+			 */
+			status = NT_STATUS_OBJECT_NAME_NOT_FOUND;
+		}
+		goto fail;
+	}
+
+	/*
+	 * fd_openat() has done an FSTAT on the handle
+	 * so update the smb_fname stat info with "truth".
+	 * from the handle.
+	 */
+	smb_fname->st = fsp->fsp_name->st;
+
+	fsp->fsp_flags.is_directory = S_ISDIR(fsp->fsp_name->st.st_ex_mode);
+
+	fsp->file_id = vfs_file_id_from_sbuf(conn, &fsp->fsp_name->st);
+
+	status = fsp_smb_fname_link(fsp,
+				    &smb_fname->fsp_link,
+				    &smb_fname->fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		goto fail;
+	}
+
+	DBG_DEBUG("fsp [%s]: OK\n", fsp_str_dbg(fsp));
+
+	talloc_set_destructor(smb_fname, smb_fname_fsp_destructor);
+	return NT_STATUS_OK;
+
+fail:
+	DBG_DEBUG("Opening pathref for [%s] failed: %s\n",
+		  smb_fname_str_dbg(smb_fname),
+		  nt_errstr(status));
+
+	fsp_set_base_fsp(fsp, NULL);
+	fd_close(fsp);
+	file_free(NULL, fsp);
+	return status;
+}
+
+/*
+ * Open an internal O_PATH based fsp for smb_fname. If O_PATH is not
+ * available, open O_RDONLY as root. Both is done in fd_open() ->
+ * non_widelink_open(), triggered by setting fsp->fsp_flags.is_pathref to
+ * true.
+ */
+NTSTATUS openat_pathref_fsp(const struct files_struct *dirfsp,
+			    struct smb_filename *smb_fname)
+{
+	connection_struct *conn = dirfsp->conn;
+	struct smb_filename *full_fname = NULL;
+	struct smb_filename *base_fname = NULL;
+	struct vfs_open_how how = { .flags = O_RDONLY|O_NONBLOCK, };
+	NTSTATUS status;
+
+	DBG_DEBUG("smb_fname [%s]\n", smb_fname_str_dbg(smb_fname));
+
+	if (smb_fname->fsp != NULL) {
+		/* We already have one for this name. */
+		DBG_DEBUG("smb_fname [%s] already has a pathref fsp.\n",
+			smb_fname_str_dbg(smb_fname));
+		return NT_STATUS_OK;
+	}
+
+	if (is_named_stream(smb_fname) &&
+	    ((conn->fs_capabilities & FILE_NAMED_STREAMS) == 0)) {
+		DBG_DEBUG("stream open [%s] on non-stream share\n",
+			  smb_fname_str_dbg(smb_fname));
+		return NT_STATUS_OBJECT_NAME_INVALID;
+	}
+
+	if (!is_named_stream(smb_fname)) {
+		/*
+		 * openat_pathref_fullname() will make "full_fname" a
+		 * talloc child of the smb_fname->fsp. Don't use
+		 * talloc_tos() to allocate it to avoid making the
+		 * talloc stackframe pool long-lived.
+		 */
+		full_fname = full_path_from_dirfsp_atname(
+			conn,
+			dirfsp,
+			smb_fname);
+		if (full_fname == NULL) {
+			status = NT_STATUS_NO_MEMORY;
+			goto fail;
+		}
+		status = openat_pathref_fullname(
+			conn, dirfsp, NULL, &full_fname, smb_fname, &how);
+		TALLOC_FREE(full_fname);
+		return status;
+	}
+
+	/*
+	 * stream open
+	 */
+	base_fname = cp_smb_filename_nostream(conn, smb_fname);
+	if (base_fname == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	full_fname = full_path_from_dirfsp_atname(
+		conn,	/* no talloc_tos(), see comment above */
+		dirfsp,
+		base_fname);
+	if (full_fname == NULL) {
+		status = NT_STATUS_NO_MEMORY;
+		goto fail;
+	}
+
+	status = openat_pathref_fullname(
+		conn, dirfsp, NULL, &full_fname, base_fname, &how);
+	TALLOC_FREE(full_fname);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("openat_pathref_fullname() failed: %s\n",
+			  nt_errstr(status));
+		goto fail;
+	}
+
+	status = open_stream_pathref_fsp(&base_fname->fsp, smb_fname);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("open_stream_pathref_fsp failed: %s\n",
+			  nt_errstr(status));
+		goto fail;
+	}
+
+	smb_fname_fsp_unlink(base_fname);
+fail:
+	TALLOC_FREE(base_fname);
+	return status;
+}
+
+/*
+ * Open a stream given an already opened base_fsp. Avoid
+ * non_widelink_open: This is only valid for the case where we have a
+ * valid non-cwd_fsp dirfsp that we can pass to SMB_VFS_OPENAT()
+ */
+NTSTATUS open_stream_pathref_fsp(
+	struct files_struct **_base_fsp,
+	struct smb_filename *smb_fname)
+{
+	struct files_struct *base_fsp = *_base_fsp;
+	connection_struct *conn = base_fsp->conn;
+	struct smb_filename *base_fname = base_fsp->fsp_name;
+	struct smb_filename *full_fname = NULL;
+	struct vfs_open_how how = { .flags = O_RDONLY|O_NONBLOCK, };
+	NTSTATUS status;
+
+	SMB_ASSERT(smb_fname->fsp == NULL);
+	SMB_ASSERT(is_named_stream(smb_fname));
+
+	full_fname = synthetic_smb_fname(
+		conn, /* no talloc_tos(), this will be long-lived */
+		base_fname->base_name,
+		smb_fname->stream_name,
+		&smb_fname->st,
+		smb_fname->twrp,
+		smb_fname->flags);
+	if (full_fname == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = openat_pathref_fullname(
+		conn, NULL, base_fsp, &full_fname, smb_fname, &how);
+	TALLOC_FREE(full_fname);
+	return status;
+}
+
+static char *path_to_strv(TALLOC_CTX *mem_ctx, const char *path)
+{
+	char *result = talloc_strdup(mem_ctx, path);
+
+	if (result == NULL) {
+		return NULL;
+	}
+	string_replace(result, '/', '\0');
+	return result;
+}
+
+NTSTATUS readlink_talloc(
+	TALLOC_CTX *mem_ctx,
+	struct files_struct *dirfsp,
+	struct smb_filename *smb_relname,
+	char **_substitute)
+{
+	struct smb_filename null_fname = {
+		.base_name = discard_const_p(char, ""),
+	};
+	char buf[PATH_MAX];
+	ssize_t ret;
+	char *substitute;
+	NTSTATUS status;
+
+	if (smb_relname == NULL) {
+		/*
+		 * We have a Linux O_PATH handle in dirfsp and want to
+		 * read its value, essentially a freadlink
+		 */
+		smb_relname = &null_fname;
+	}
+
+	ret = SMB_VFS_READLINKAT(
+		dirfsp->conn, dirfsp, smb_relname, buf, sizeof(buf));
+	if (ret < 0) {
+		status = map_nt_error_from_unix(errno);
+		DBG_DEBUG("SMB_VFS_READLINKAT() failed: %s\n",
+			  strerror(errno));
+		return status;
+	}
+
+	if ((size_t)ret == sizeof(buf)) {
+		/*
+		 * Do we need symlink targets longer than PATH_MAX?
+		 */
+		DBG_DEBUG("Got full %zu bytes from readlink, too long\n",
+			  sizeof(buf));
+		return NT_STATUS_BUFFER_OVERFLOW;
+	}
+
+	substitute = talloc_strndup(mem_ctx, buf, ret);
+	if (substitute == NULL) {
+		DBG_DEBUG("talloc_strndup() failed\n");
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	*_substitute = substitute;
+	return NT_STATUS_OK;
+}
+
+NTSTATUS read_symlink_reparse(
+	TALLOC_CTX *mem_ctx,
+	struct files_struct *dirfsp,
+	struct smb_filename *smb_relname,
+	struct symlink_reparse_struct **_symlink)
+{
+	struct symlink_reparse_struct *symlink = NULL;
+	NTSTATUS status;
+
+	symlink = talloc_zero(mem_ctx, struct symlink_reparse_struct);
+	if (symlink == NULL) {
+		goto nomem;
+	}
+
+	status = readlink_talloc(
+		symlink, dirfsp, smb_relname, &symlink->substitute_name);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("readlink_talloc failed: %s\n", nt_errstr(status));
+		goto fail;
+	}
+
+	if (symlink->substitute_name[0] == '/') {
+		char *subdir_path = NULL;
+		char *abs_target_canon = NULL;
+		const char *relative = NULL;
+		bool in_share;
+
+		subdir_path = talloc_asprintf(talloc_tos(),
+					      "%s/%s",
+					      dirfsp->conn->connectpath,
+					      dirfsp->fsp_name->base_name);
+		if (subdir_path == NULL) {
+			goto nomem;
+		}
+
+		abs_target_canon =
+			canonicalize_absolute_path(talloc_tos(),
+						   symlink->substitute_name);
+		if (abs_target_canon == NULL) {
+			goto nomem;
+		}
+
+		in_share = subdir_of(subdir_path,
+				     strlen(subdir_path),
+				     abs_target_canon,
+				     &relative);
+		if (in_share) {
+			TALLOC_FREE(symlink->substitute_name);
+			symlink->substitute_name =
+				talloc_strdup(symlink, relative);
+			if (symlink->substitute_name == NULL) {
+				goto nomem;
+			}
+		}
+	}
+
+	if (!IS_DIRECTORY_SEP(symlink->substitute_name[0])) {
+		symlink->flags |= SYMLINK_FLAG_RELATIVE;
+	}
+
+	*_symlink = symlink;
+	return NT_STATUS_OK;
+nomem:
+	status = NT_STATUS_NO_MEMORY;
+fail:
+	TALLOC_FREE(symlink);
+	return status;
+}
+
+static bool full_path_extend(char **dir, const char *atname)
+{
+	talloc_asprintf_addbuf(dir,
+			       "%s%s",
+			       (*dir)[0] == '\0' ? "" : "/",
+			       atname);
+	return (*dir) != NULL;
+}
+
+NTSTATUS create_open_symlink_err(TALLOC_CTX *mem_ctx,
+				 files_struct *dirfsp,
+				 struct smb_filename *smb_relname,
+				 struct open_symlink_err **_err)
+{
+	struct open_symlink_err *err = NULL;
+	NTSTATUS status;
+
+	err = talloc_zero(mem_ctx, struct open_symlink_err);
+	if (err == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = read_symlink_reparse(err, dirfsp, smb_relname, &err->reparse);
+	if (!NT_STATUS_IS_OK(status)) {
+		TALLOC_FREE(err);
+		return status;
+	}
+
+	*_err = err;
+	return NT_STATUS_OK;
+}
+
+/*
+ * Create the memcache-key for GETREALFILENAME_CACHE: This supplements
+ * the stat cache for the last component to be looked up. Cache
+ * contents is the correctly capitalized translation of the parameter
+ * "name" as it exists on disk. This is indexed by inode of the dirfsp
+ * and name, and contrary to stat_cahce_lookup() it does not
+ * vfs_stat() the last component. This will be taken care of by an
+ * attempt to do a openat_pathref_fsp().
+ */
+static bool get_real_filename_cache_key(TALLOC_CTX *mem_ctx,
+					struct files_struct *dirfsp,
+					const char *name,
+					DATA_BLOB *_key)
+{
+	struct file_id fid = vfs_file_id_from_sbuf(dirfsp->conn,
+						   &dirfsp->fsp_name->st);
+	char *upper = NULL;
+	uint8_t *key = NULL;
+	size_t namelen, keylen;
+
+	upper = talloc_strdup_upper(mem_ctx, name);
+	if (upper == NULL) {
+		return false;
+	}
+	namelen = talloc_get_size(upper);
+
+	keylen = namelen + sizeof(fid);
+	if (keylen < sizeof(fid)) {
+		TALLOC_FREE(upper);
+		return false;
+	}
+
+	key = talloc_size(mem_ctx, keylen);
+	if (key == NULL) {
+		TALLOC_FREE(upper);
+		return false;
+	}
+
+	memcpy(key, &fid, sizeof(fid));
+	memcpy(key + sizeof(fid), upper, namelen);
+	TALLOC_FREE(upper);
+
+	*_key = (DATA_BLOB){
+		.data = key,
+		.length = keylen,
+	};
+	return true;
+}
+
+static int smb_vfs_openat_ci(TALLOC_CTX *mem_ctx,
+			     bool case_sensitive,
+			     struct connection_struct *conn,
+			     struct files_struct *dirfsp,
+			     struct smb_filename *smb_fname_rel,
+			     files_struct *fsp,
+			     const struct vfs_open_how *how)
+{
+	char *orig_base_name = smb_fname_rel->base_name;
+	DATA_BLOB cache_key = {
+		.data = NULL,
+	};
+	DATA_BLOB cache_value = {
+		.data = NULL,
+	};
+	NTSTATUS status;
+	int fd;
+	bool ok;
+
+	fd = SMB_VFS_OPENAT(conn, dirfsp, smb_fname_rel, fsp, how);
+	if ((fd >= 0) || case_sensitive) {
+		return fd;
+	}
+	if (errno != ENOENT) {
+		return -1;
+	}
+
+	if (!lp_stat_cache()) {
+		goto lookup;
+	}
+
+	ok = get_real_filename_cache_key(mem_ctx,
+					 dirfsp,
+					 orig_base_name,
+					 &cache_key);
+	if (!ok) {
+		/*
+		 * probably ENOMEM, just bail
+		 */
+		errno = ENOMEM;
+		return -1;
+	}
+
+	DO_PROFILE_INC(statcache_lookups);
+
+	ok = memcache_lookup(NULL,
+			     GETREALFILENAME_CACHE,
+			     cache_key,
+			     &cache_value);
+	if (!ok) {
+		DO_PROFILE_INC(statcache_misses);
+		goto lookup;
+	}
+	DO_PROFILE_INC(statcache_hits);
+
+	smb_fname_rel->base_name = talloc_strndup(mem_ctx,
+						  (char *)cache_value.data,
+						  cache_value.length);
+	if (smb_fname_rel->base_name == NULL) {
+		TALLOC_FREE(cache_key.data);
+		smb_fname_rel->base_name = orig_base_name;
+		errno = ENOMEM;
+		return -1;
+	}
+
+	if (IS_VETO_PATH(dirfsp->conn, smb_fname_rel->base_name)) {
+		DBG_DEBUG("veto files rejecting last component %s\n",
+			  smb_fname_str_dbg(smb_fname_rel));
+		TALLOC_FREE(cache_key.data);
+		smb_fname_rel->base_name = orig_base_name;
+		errno = EPERM;
+		return -1;
+	}
+
+	fd = SMB_VFS_OPENAT(conn, dirfsp, smb_fname_rel, fsp, how);
+	if (fd >= 0) {
+		TALLOC_FREE(cache_key.data);
+		return fd;
+	}
+
+	memcache_delete(NULL, GETREALFILENAME_CACHE, cache_key);
+
+	/*
+	 * For the "new filename" case we need to preserve the
+	 * capitalization the client sent us, see
+	 * https://bugzilla.samba.org/show_bug.cgi?id=15481
+	 */
+	TALLOC_FREE(smb_fname_rel->base_name);
+	smb_fname_rel->base_name = orig_base_name;
+
+lookup:
+
+	status = get_real_filename_at(dirfsp,
+				      orig_base_name,
+				      mem_ctx,
+				      &smb_fname_rel->base_name);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("get_real_filename_at() failed: %s\n",
+			  nt_errstr(status));
+		errno = ENOENT;
+		return -1;
+	}
+
+	if (IS_VETO_PATH(conn, smb_fname_rel->base_name)) {
+		DBG_DEBUG("found veto files path component "
+			  "%s => %s\n",
+			  orig_base_name,
+			  smb_fname_rel->base_name);
+		TALLOC_FREE(smb_fname_rel->base_name);
+		smb_fname_rel->base_name = orig_base_name;
+		errno = ENOENT;
+		return -1;
+	}
+
+	fd = SMB_VFS_OPENAT(conn, dirfsp, smb_fname_rel, fsp, how);
+
+	if ((fd >= 0) && (cache_key.data != NULL)) {
+		DATA_BLOB value = {
+			.data = (uint8_t *)smb_fname_rel->base_name,
+			.length = strlen(smb_fname_rel->base_name) + 1,
+		};
+
+		memcache_add(NULL, GETREALFILENAME_CACHE, cache_key, value);
+		TALLOC_FREE(cache_key.data);
+	}
+
+	return fd;
+}
+
+NTSTATUS openat_pathref_fsp_nosymlink(TALLOC_CTX *mem_ctx,
+				      struct connection_struct *conn,
+				      struct files_struct *in_dirfsp,
+				      const char *path_in,
+				      NTTIME twrp,
+				      bool posix,
+				      struct smb_filename **_smb_fname,
+				      struct open_symlink_err **_symlink_err)
+{
+	struct files_struct *dirfsp = in_dirfsp;
+	struct smb_filename full_fname = {
+		.base_name = NULL,
+		.twrp = twrp,
+		.flags = posix ? SMB_FILENAME_POSIX_PATH : 0,
+	};
+	struct smb_filename rel_fname = {
+		.base_name = NULL,
+		.twrp = twrp,
+		.flags = full_fname.flags,
+	};
+	struct smb_filename *result = NULL;
+	struct open_symlink_err *symlink_err = NULL;
+	struct files_struct *fsp = NULL;
+	char *path = NULL, *next = NULL;
+	bool ok, is_toplevel;
+	int fd;
+	NTSTATUS status;
+	struct vfs_open_how how = {
+		.flags = O_NOFOLLOW | O_NONBLOCK,
+		.mode = 0,
+	};
+
+	DBG_DEBUG("path_in=%s\n", path_in);
+
+	status = fsp_new(conn, conn, &fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("fsp_new() failed: %s\n", nt_errstr(status));
+		goto fail;
+	}
+
+	GetTimeOfDay(&fsp->open_time);
+	fsp_set_gen_id(fsp);
+	ZERO_STRUCT(conn->sconn->fsp_fi_cache);
+
+	fsp->fsp_name = &full_fname;
+
+#ifdef O_PATH
+	/*
+	 * Add O_PATH manually, doing this by setting
+	 * fsp->fsp_flags.is_pathref will make us become_root() in the
+	 * non-O_PATH case, which would cause a security problem.
+	 */
+	how.flags |= O_PATH;
+#else
+#ifdef O_SEARCH
+	/*
+	 * O_SEARCH just checks for the "x" bit. We are traversing
+	 * directories, so we don't need the implicit O_RDONLY ("r"
+	 * permissions) but only the "x"-permissions requested by
+	 * O_SEARCH. We need either O_PATH or O_SEARCH to correctly
+	 * function, without either we will incorrectly require also
+	 * the "r" bit when traversing the directory hierarchy.
+	 */
+	how.flags |= O_SEARCH;
+#endif
+#endif
+
+	is_toplevel = (dirfsp == dirfsp->conn->cwd_fsp);
+	is_toplevel |= ISDOT(dirfsp->fsp_name->base_name);
+
+	full_fname.base_name =
+		talloc_strdup(talloc_tos(),
+			      is_toplevel ? "" : dirfsp->fsp_name->base_name);
+	if (full_fname.base_name == NULL) {
+		DBG_DEBUG("talloc_strdup() failed\n");
+		goto nomem;
+	}
+
+	/*
+	 * First split the path into individual components.
+	 */
+	path = path_to_strv(talloc_tos(), path_in);
+	if (path == NULL) {
+		DBG_DEBUG("path_to_strv() failed\n");
+		goto nomem;
+	}
+
+	/*
+	 * First we loop over all components
+	 * in order to verify, there's no '.' or '..'
+	 */
+	rel_fname.base_name = path;
+	while (rel_fname.base_name != NULL) {
+
+		next = strv_next(path, rel_fname.base_name);
+
+		/*
+		 * Path sanitizing further up has cleaned or rejected
+		 * empty path components. Assert this here.
+		 */
+		SMB_ASSERT(rel_fname.base_name[0] != '\0');
+
+		if (ISDOT(rel_fname.base_name) ||
+		    ISDOTDOT(rel_fname.base_name)) {
+			DBG_DEBUG("%s contains a dot\n", path_in);
+			status = NT_STATUS_OBJECT_NAME_INVALID;
+			goto fail;
+		}
+
+		/* Check veto files. */
+		if (IS_VETO_PATH(conn, rel_fname.base_name)) {
+			DBG_DEBUG("%s contains veto files path component %s\n",
+				  path_in, rel_fname.base_name);
+			status = NT_STATUS_OBJECT_PATH_NOT_FOUND;
+			goto fail;
+		}
+
+		rel_fname.base_name = next;
+	}
+
+	if (conn->open_how_resolve & VFS_OPEN_HOW_RESOLVE_NO_SYMLINKS) {
+
+		/*
+		 * Try a direct openat2 with RESOLVE_NO_SYMLINKS to
+		 * avoid the openat/close loop further down.
+		 */
+
+		rel_fname.base_name = discard_const_p(char, path_in);
+		how.resolve = VFS_OPEN_HOW_RESOLVE_NO_SYMLINKS;
+
+		fd = SMB_VFS_OPENAT(conn, dirfsp, &rel_fname, fsp, &how);
+		if (fd >= 0) {
+			fsp_set_fd(fsp, fd);
+			ok = full_path_extend(&full_fname.base_name,
+					      rel_fname.base_name);
+			if (!ok) {
+				goto nomem;
+			}
+			goto done;
+		}
+
+		status = map_nt_error_from_unix(errno);
+		DBG_DEBUG("SMB_VFS_OPENAT(%s, %s, RESOLVE_NO_SYMLINKS) "
+			  "returned %d %s => %s\n",
+			  smb_fname_str_dbg(dirfsp->fsp_name), path_in,
+			  errno, strerror(errno), nt_errstr(status));
+		SMB_ASSERT(fd == -1);
+		switch (errno) {
+		case ENOSYS:
+			/*
+			 * We got ENOSYS, so fallback to the old code
+			 * if the kernel doesn't support openat2() yet.
+			 */
+			break;
+
+		case ELOOP:
+		case ENOTDIR:
+			/*
+			 * For ELOOP we also fallback in order to
+			 * return the correct information with
+			 * NT_STATUS_STOPPED_ON_SYMLINK.
+			 *
+			 * O_NOFOLLOW|O_DIRECTORY results in
+			 * ENOTDIR instead of ELOOP for the final
+			 * component.
+			 */
+			break;
+
+		case ENOENT:
+			/*
+			 * If we got ENOENT, the filesystem could
+			 * be case sensitive. For now we only do
+			 * the get_real_filename_at() dance in
+			 * the fallback loop below.
+			 */
+			break;
+
+		default:
+			goto fail;
+		}
+
+		/*
+		 * Just fallback to the openat loop
+		 */
+		how.resolve = 0;
+	}
+
+	/*
+	 * Now we loop over all components
+	 * opening each one and using it
+	 * as dirfd for the next one.
+	 *
+	 * It means we can detect symlinks
+	 * within the path.
+	 */
+	rel_fname.base_name = path;
+next:
+	next = strv_next(path, rel_fname.base_name);
+
+	fd = smb_vfs_openat_ci(talloc_tos(),
+			       posix || conn->case_sensitive,
+			       conn,
+			       dirfsp,
+			       &rel_fname,
+			       fsp,
+			       &how);
+
+#ifndef O_PATH
+	if ((fd == -1) && (errno == ELOOP)) {
+		int ret;
+
+		/*
+		 * openat() hit a symlink. With O_PATH we open the
+		 * symlink and get ENOTDIR in the next round, see
+		 * below.
+		 */
+
+		status = create_open_symlink_err(mem_ctx,
+						 dirfsp,
+						 &rel_fname,
+						 &symlink_err);
+		if (!NT_STATUS_IS_OK(status)) {
+			DBG_DEBUG("create_open_symlink_err failed: %s\n",
+				  nt_errstr(status));
+			goto fail;
+		}
+
+		if (next != NULL) {
+			size_t parsed = next - path;
+			size_t len = talloc_get_size(path);
+			symlink_err->unparsed = len - parsed;
+		}
+
+		/*
+		 * We know rel_fname is a symlink, now fill in the
+		 * rest of the metadata for our callers.
+		 */
+
+		ret = SMB_VFS_FSTATAT(conn,
+				      dirfsp,
+				      &rel_fname,
+				      &symlink_err->st,
+				      AT_SYMLINK_NOFOLLOW);
+		if (ret == -1) {
+			status = map_nt_error_from_unix(errno);
+			DBG_DEBUG("SMB_VFS_FSTATAT(%s/%s) failed: %s\n",
+				  fsp_str_dbg(dirfsp),
+				  rel_fname.base_name,
+				  strerror(errno));
+			TALLOC_FREE(symlink_err);
+			goto fail;
+		}
+
+		if (!S_ISLNK(symlink_err->st.st_ex_mode)) {
+			/*
+			 * Hit a race: readlink_talloc() worked before
+			 * the fstatat(), but rel_fname changed to
+			 * something that's not a symlink.
+			 */
+			status = NT_STATUS_OBJECT_NAME_NOT_FOUND;
+			TALLOC_FREE(symlink_err);
+			goto fail;
+		}
+
+		status = NT_STATUS_STOPPED_ON_SYMLINK;
+		goto fail;
+	}
+#endif
+
+	if ((fd == -1) && (errno == ENOTDIR)) {
+		size_t parsed, len;
+
+		/*
+		 * dirfsp does not point at a directory, try a
+		 * freadlink.
+		 */
+
+		status = create_open_symlink_err(mem_ctx,
+						 dirfsp,
+						 NULL,
+						 &symlink_err);
+
+		if (!NT_STATUS_IS_OK(status)) {
+			DBG_DEBUG("create_open_symlink_err failed: %s\n",
+				  nt_errstr(status));
+			status = NT_STATUS_NOT_A_DIRECTORY;
+			goto fail;
+		}
+
+		parsed = rel_fname.base_name - path;
+		len = talloc_get_size(path);
+		symlink_err->unparsed = len - parsed;
+
+		symlink_err->st = dirfsp->fsp_name->st;
+
+		status = NT_STATUS_STOPPED_ON_SYMLINK;
+		goto fail;
+	}
+
+	if (fd == -1) {
+		status = map_nt_error_from_unix(errno);
+		DBG_DEBUG("SMB_VFS_OPENAT() failed: %s\n",
+			  strerror(errno));
+		goto fail;
+	}
+	fsp_set_fd(fsp, fd);
+
+	ok = full_path_extend(&full_fname.base_name, rel_fname.base_name);
+	if (!ok) {
+		goto nomem;
+	}
+
+	if (next != NULL) {
+		struct files_struct *tmp = NULL;
+
+		if (dirfsp != in_dirfsp) {
+			fd_close(dirfsp);
+		}
+
+		tmp = dirfsp;
+		dirfsp = fsp;
+
+		if (tmp == in_dirfsp) {
+			status = fsp_new(conn, conn, &fsp);
+			if (!NT_STATUS_IS_OK(status)) {
+				DBG_DEBUG("fsp_new() failed: %s\n",
+					  nt_errstr(status));
+				goto fail;
+			}
+			fsp->fsp_name = &full_fname;
+		} else {
+			fsp = tmp;
+		}
+
+		rel_fname.base_name = next;
+
+		goto next;
+	}
+
+	if (dirfsp != in_dirfsp) {
+		SMB_ASSERT(fsp_get_pathref_fd(dirfsp) != -1);
+		fd_close(dirfsp);
+		dirfsp->fsp_name = NULL;
+		file_free(NULL, dirfsp);
+		dirfsp = NULL;
+	}
+
+done:
+	fsp->fsp_flags.is_pathref = true;
+	fsp->fsp_name = NULL;
+
+	status = fsp_set_smb_fname(fsp, &full_fname);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("fsp_set_smb_fname() failed: %s\n",
+			  nt_errstr(status));
+		goto fail;
+	}
+
+	status = vfs_stat_fsp(fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("vfs_stat_fsp(%s) failed: %s\n",
+			  fsp_str_dbg(fsp),
+			  nt_errstr(status));
+		goto fail;
+	}
+
+	if (S_ISLNK(fsp->fsp_name->st.st_ex_mode)) {
+		/*
+		 * Last component was a symlink we opened with O_PATH, fail it
+		 * here.
+		 */
+		status = create_open_symlink_err(mem_ctx,
+						 fsp,
+						 NULL,
+						 &symlink_err);
+		if (!NT_STATUS_IS_OK(status)) {
+			return status;
+		}
+		symlink_err->st = fsp->fsp_name->st;
+
+		status = NT_STATUS_STOPPED_ON_SYMLINK;
+		goto fail;
+	}
+
+	/*
+	 * We must correctly set fsp->file_id as code inside
+	 * open.c will use this to check if delete_on_close
+	 * has been set on the dirfsp.
+	 */
+	fsp->file_id = vfs_file_id_from_sbuf(conn, &fsp->fsp_name->st);
+
+	result = cp_smb_filename(mem_ctx, fsp->fsp_name);
+	if (result == NULL) {
+		DBG_DEBUG("cp_smb_filename() failed\n");
+		goto nomem;
+	}
+
+	status = fsp_smb_fname_link(fsp,
+					&result->fsp_link,
+					&result->fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		goto fail;
+	}
+	talloc_set_destructor(result, smb_fname_fsp_destructor);
+
+	*_smb_fname = result;
+
+	DBG_DEBUG("returning %s\n", smb_fname_str_dbg(result));
+
+	return NT_STATUS_OK;
+
+nomem:
+	status = NT_STATUS_NO_MEMORY;
+fail:
+	if (fsp != NULL) {
+		if (fsp_get_pathref_fd(fsp) != -1) {
+			fd_close(fsp);
+		}
+		file_free(NULL, fsp);
+		fsp = NULL;
+	}
+
+	if ((dirfsp != NULL) && (dirfsp != in_dirfsp)) {
+		SMB_ASSERT(fsp_get_pathref_fd(dirfsp) != -1);
+		fd_close(dirfsp);
+		dirfsp->fsp_name = NULL;
+		file_free(NULL, dirfsp);
+		dirfsp = NULL;
+	}
+
+	if (NT_STATUS_EQUAL(status, NT_STATUS_STOPPED_ON_SYMLINK)) {
+		*_symlink_err = symlink_err;
+	}
+
+	TALLOC_FREE(path);
+	return status;
+}
+
+/*
+ * Open smb_fname_rel->fsp as a pathref fsp with a case insensitive
+ * fallback using GETREALFILENAME_CACHE and get_real_filename_at() if
+ * the first attempt based on the filename sent by the client gives
+ * ENOENT.
+ */
+NTSTATUS openat_pathref_fsp_lcomp(struct files_struct *dirfsp,
+				  struct smb_filename *smb_fname_rel,
+				  uint32_t ucf_flags)
+{
+	struct connection_struct *conn = dirfsp->conn;
+	const char *orig_rel_base_name = smb_fname_rel->base_name;
+	struct files_struct *fsp = NULL;
+	struct smb_filename *full_fname = NULL;
+	struct vfs_open_how how = {
+		.flags = O_RDONLY | O_NONBLOCK | O_NOFOLLOW,
+	};
+	NTSTATUS status;
+	int ret, fd;
+
+	/*
+	 * Make sure we don't need of the all the magic in
+	 * openat_pathref_fsp() with regards non_widelink_open etc.
+	 */
+
+	SMB_ASSERT((smb_fname_rel->fsp == NULL) &&
+		   (dirfsp != dirfsp->conn->cwd_fsp) &&
+		   (strchr_m(smb_fname_rel->base_name, '/') == NULL) &&
+		   !is_named_stream(smb_fname_rel));
+
+	SET_STAT_INVALID(smb_fname_rel->st);
+
+	/* Check veto files - only looks at last component. */
+	if (IS_VETO_PATH(dirfsp->conn, smb_fname_rel->base_name)) {
+		DBG_DEBUG("veto files rejecting last component %s\n",
+			  smb_fname_str_dbg(smb_fname_rel));
+		return NT_STATUS_NETWORK_OPEN_RESTRICTION;
+	}
+
+	status = fsp_new(conn, conn, &fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("fsp_new() failed: %s\n", nt_errstr(status));
+		return status;
+	}
+
+	GetTimeOfDay(&fsp->open_time);
+	fsp_set_gen_id(fsp);
+	ZERO_STRUCT(conn->sconn->fsp_fi_cache);
+
+	fsp->fsp_flags.is_pathref = true;
+
+	full_fname = full_path_from_dirfsp_atname(conn, dirfsp, smb_fname_rel);
+	if (full_fname == NULL) {
+		DBG_DEBUG("full_path_from_dirfsp_atname(%s/%s) failed\n",
+			  dirfsp->fsp_name->base_name,
+			  smb_fname_rel->base_name);
+		file_free(NULL, fsp);
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = fsp_attach_smb_fname(fsp, &full_fname);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("fsp_attach_smb_fname(fsp, %s) failed: %s\n",
+			  smb_fname_str_dbg(full_fname),
+			  nt_errstr(status));
+		file_free(NULL, fsp);
+		return status;
+	}
+
+	fd = smb_vfs_openat_ci(smb_fname_rel,
+			       (ucf_flags & UCF_POSIX_PATHNAMES) ||
+				       conn->case_sensitive,
+			       conn,
+			       dirfsp,
+			       smb_fname_rel,
+			       fsp,
+			       &how);
+
+	if ((fd == -1) && (errno == ENOENT)) {
+		status = map_nt_error_from_unix(errno);
+		DBG_DEBUG("smb_vfs_openat(%s/%s) failed: %s\n",
+			  dirfsp->fsp_name->base_name,
+			  smb_fname_rel->base_name,
+			  strerror(errno));
+		file_free(NULL, fsp);
+		return status;
+	}
+
+	if (smb_fname_rel->base_name != orig_rel_base_name) {
+		struct smb_filename new_fullname = *smb_fname_rel;
+
+		DBG_DEBUG("rel->base_name changed from %s to %s\n",
+			  orig_rel_base_name,
+			  smb_fname_rel->base_name);
+
+		new_fullname.base_name = full_path_from_dirfsp_at_basename(
+			talloc_tos(), dirfsp, new_fullname.base_name);
+		if (new_fullname.base_name == NULL) {
+			fd_close(fsp);
+			file_free(NULL, fsp);
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		status = fsp_set_smb_fname(fsp, &new_fullname);
+		if (!NT_STATUS_IS_OK(status)) {
+			fd_close(fsp);
+			file_free(NULL, fsp);
+			return status;
+		}
+	}
+
+	fsp_set_fd(fsp, fd);
+
+	if (fd >= 0) {
+		ret = SMB_VFS_FSTAT(fsp, &fsp->fsp_name->st);
+	} else {
+		ret = SMB_VFS_FSTATAT(fsp->conn,
+				      dirfsp,
+				      smb_fname_rel,
+				      &fsp->fsp_name->st,
+				      AT_SYMLINK_NOFOLLOW);
+	}
+	if (ret == -1) {
+		status = map_nt_error_from_unix(errno);
+		DBG_DEBUG("SMB_VFS_%sSTAT(%s/%s) failed: %s\n",
+			  (fd >= 0) ? "F" : "",
+			  dirfsp->fsp_name->base_name,
+			  smb_fname_rel->base_name,
+			  strerror(errno));
+		fd_close(fsp);
+		file_free(NULL, fsp);
+		return status;
+	}
+
+	fsp->fsp_flags.is_directory = S_ISDIR(fsp->fsp_name->st.st_ex_mode);
+	fsp->file_id = vfs_file_id_from_sbuf(conn, &fsp->fsp_name->st);
+
+	smb_fname_rel->st = fsp->fsp_name->st;
+
+	status = fsp_smb_fname_link(fsp,
+				    &smb_fname_rel->fsp_link,
+				    &smb_fname_rel->fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("fsp_smb_fname_link() failed: %s\n",
+			  nt_errstr(status));
+		fd_close(fsp);
+		file_free(NULL, fsp);
+		return status;
+	}
+
+	DBG_DEBUG("fsp [%s]: OK, fd=%d\n", fsp_str_dbg(fsp), fd);
+
+	talloc_set_destructor(smb_fname_rel, smb_fname_fsp_destructor);
+	return NT_STATUS_OK;
+}
+
+void smb_fname_fsp_unlink(struct smb_filename *smb_fname)
+{
+	talloc_set_destructor(smb_fname, NULL);
+	smb_fname->fsp = NULL;
+	destroy_fsp_smb_fname_link(&smb_fname->fsp_link);
+}
+
+/*
+ * Move any existing embedded fsp refs from the src name to the
+ * destination. It's safe to call this on src smb_fname's that have no embedded
+ * pathref fsp.
+ */
+NTSTATUS move_smb_fname_fsp_link(struct smb_filename *smb_fname_dst,
+				 struct smb_filename *smb_fname_src)
+{
+	NTSTATUS status;
+
+	/*
+	 * The target should always not be linked yet!
+	 */
+	SMB_ASSERT(smb_fname_dst->fsp == NULL);
+	SMB_ASSERT(smb_fname_dst->fsp_link == NULL);
+
+	if (smb_fname_src->fsp == NULL) {
+		return NT_STATUS_OK;
+	}
+
+	status = fsp_smb_fname_link(smb_fname_src->fsp,
+				    &smb_fname_dst->fsp_link,
+				    &smb_fname_dst->fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	talloc_set_destructor(smb_fname_dst, smb_fname_fsp_destructor);
+
+	smb_fname_fsp_unlink(smb_fname_src);
+
+	return NT_STATUS_OK;
+}
+
+static int fsp_ref_no_close_destructor(struct smb_filename *smb_fname)
+{
+	destroy_fsp_smb_fname_link(&smb_fname->fsp_link);
+	return 0;
+}
+
+NTSTATUS reference_smb_fname_fsp_link(struct smb_filename *smb_fname_dst,
+				      const struct smb_filename *smb_fname_src)
+{
+	NTSTATUS status;
+
+	/*
+	 * The target should always not be linked yet!
+	 */
+	SMB_ASSERT(smb_fname_dst->fsp == NULL);
+	SMB_ASSERT(smb_fname_dst->fsp_link == NULL);
+
+	if (smb_fname_src->fsp == NULL) {
+		return NT_STATUS_OK;
+	}
+
+	status = fsp_smb_fname_link(smb_fname_src->fsp,
+				    &smb_fname_dst->fsp_link,
+				    &smb_fname_dst->fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	talloc_set_destructor(smb_fname_dst, fsp_ref_no_close_destructor);
+
+	return NT_STATUS_OK;
+}
+
+/**
+ * Create an smb_fname and open smb_fname->fsp pathref
+ **/
+NTSTATUS synthetic_pathref(TALLOC_CTX *mem_ctx,
+			   struct files_struct *dirfsp,
+			   const char *base_name,
+			   const char *stream_name,
+			   const SMB_STRUCT_STAT *psbuf,
+			   NTTIME twrp,
+			   uint32_t flags,
+			   struct smb_filename **_smb_fname)
+{
+	struct smb_filename *smb_fname = NULL;
+	NTSTATUS status;
+
+	smb_fname = synthetic_smb_fname(mem_ctx,
+					base_name,
+					stream_name,
+					psbuf,
+					twrp,
+					flags);
+	if (smb_fname == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = openat_pathref_fsp(dirfsp, smb_fname);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_NOTICE("opening [%s] failed\n",
+			smb_fname_str_dbg(smb_fname));
+		TALLOC_FREE(smb_fname);
+		return status;
+	}
+
+	*_smb_fname = smb_fname;
+	return NT_STATUS_OK;
+}
+
+/**
+ * Turn a path into a parent pathref and atname
+ *
+ * This returns the parent pathref in _parent and the name relative to it. If
+ * smb_fname was a pathref (ie smb_fname->fsp != NULL), then _atname will be a
+ * pathref as well, ie _atname->fsp will point at the same fsp as
+ * smb_fname->fsp.
+ **/
+NTSTATUS parent_pathref(TALLOC_CTX *mem_ctx,
+			struct files_struct *dirfsp,
+			const struct smb_filename *smb_fname,
+			struct smb_filename **_parent,
+			struct smb_filename **_atname)
+{
+	struct smb_filename *parent = NULL;
+	struct smb_filename *atname = NULL;
+	NTSTATUS status;
+
+	status = SMB_VFS_PARENT_PATHNAME(dirfsp->conn,
+					 mem_ctx,
+					 smb_fname,
+					 &parent,
+					 &atname);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	/*
+	 * We know that the parent name must
+	 * exist, and the name has been canonicalized
+	 * even if this was a POSIX pathname.
+	 * Ensure that we follow symlinks for
+	 * the parent. See the torture test
+	 * POSIX-SYMLINK-PARENT for details.
+	 */
+	parent->flags &= ~SMB_FILENAME_POSIX_PATH;
+
+	status = openat_pathref_fsp(dirfsp, parent);
+	if (!NT_STATUS_IS_OK(status)) {
+		TALLOC_FREE(parent);
+		return status;
+	}
+
+	status = reference_smb_fname_fsp_link(atname, smb_fname);
+	if (!NT_STATUS_IS_OK(status)) {
+		TALLOC_FREE(parent);
+		return status;
+	}
+
+	*_parent = parent;
+	*_atname = atname;
+	return NT_STATUS_OK;
+}
+
+static bool close_file_in_loop(struct files_struct *fsp,
+			       enum file_close_type close_type)
+{
+	if (fsp_is_alternate_stream(fsp)) {
+		/*
+		 * This is a stream, it can't be a base
+		 */
+		SMB_ASSERT(fsp->stream_fsp == NULL);
+		SMB_ASSERT(fsp->base_fsp->stream_fsp == fsp);
+
+		/*
+		 * Remove the base<->stream link so that
+		 * close_file_free() does not close fsp->base_fsp as
+		 * well. This would destroy walking the linked list of
+		 * fsps.
+		 */
+		fsp->base_fsp->stream_fsp = NULL;
+		fsp->base_fsp = NULL;
+
+		close_file_free(NULL, &fsp, close_type);
+		return NULL;
+	}
+
+	if (fsp->stream_fsp != NULL) {
+		/*
+		 * This is the base of a stream.
+		 */
+		SMB_ASSERT(fsp->stream_fsp->base_fsp == fsp);
+
+		/*
+		 * Remove the base<->stream link. This will make fsp
+		 * look like a normal fsp for the next round.
+		 */
+		fsp->stream_fsp->base_fsp = NULL;
+		fsp->stream_fsp = NULL;
+
+		/*
+		 * Have us called back a second time. In the second
+		 * round, "fsp" now looks like a normal fsp.
+		 */
+		return false;
+	}
+
+	close_file_free(NULL, &fsp, close_type);
+	return true;
+}
+
+/****************************************************************************
+ Close all open files for a connection.
+****************************************************************************/
+
+struct file_close_conn_state {
+	struct connection_struct *conn;
+	enum file_close_type close_type;
+	bool fsp_left_behind;
+};
+
+static struct files_struct *file_close_conn_fn(
+	struct files_struct *fsp,
+	void *private_data)
+{
+	struct file_close_conn_state *state = private_data;
+	bool did_close;
+
+	if (fsp->conn != state->conn) {
+		return NULL;
+	}
+
+	if (fsp->op != NULL && fsp->op->global->durable) {
+		/*
+		 * A tree disconnect closes a durable handle
+		 */
+		fsp->op->global->durable = false;
+	}
+
+	did_close = close_file_in_loop(fsp, state->close_type);
+	if (!did_close) {
+		state->fsp_left_behind = true;
+	}
+
+	return NULL;
+}
+
+void file_close_conn(connection_struct *conn, enum file_close_type close_type)
+{
+	struct file_close_conn_state state = { .conn = conn,
+					       .close_type = close_type };
+
+	files_forall(conn->sconn, file_close_conn_fn, &state);
+
+	if (state.fsp_left_behind) {
+		state.fsp_left_behind = false;
+		files_forall(conn->sconn, file_close_conn_fn, &state);
+		SMB_ASSERT(!state.fsp_left_behind);
+	}
+}
+
+/****************************************************************************
+ Initialise file structures.
+****************************************************************************/
+
+static int files_max_open_fds;
+
+bool file_init_global(void)
+{
+	int request_max = lp_max_open_files();
+	int real_lim;
+	int real_max;
+
+	if (files_max_open_fds != 0) {
+		return true;
+	}
+
+	/*
+	 * Set the max_open files to be the requested
+	 * max plus a fudgefactor to allow for the extra
+	 * fd's we need such as log files etc...
+	 */
+	real_lim = set_maxfiles(request_max + MAX_OPEN_FUDGEFACTOR);
+
+	real_max = real_lim - MAX_OPEN_FUDGEFACTOR;
+
+	if (real_max + FILE_HANDLE_OFFSET + MAX_OPEN_PIPES > 65536) {
+		real_max = 65536 - FILE_HANDLE_OFFSET - MAX_OPEN_PIPES;
+	}
+
+	if (real_max != request_max) {
+		DEBUG(1, ("file_init_global: Information only: requested %d "
+			  "open files, %d are available.\n",
+			  request_max, real_max));
+	}
+
+	SMB_ASSERT(real_max > 100);
+
+	files_max_open_fds = real_max;
+	return true;
+}
+
+bool file_init(struct smbd_server_connection *sconn)
+{
+	bool ok;
+
+	ok = file_init_global();
+	if (!ok) {
+		return false;
+	}
+
+	sconn->real_max_open_files = files_max_open_fds;
+
+	return true;
+}
+
+/****************************************************************************
+ Close files open by a specified vuid.
+****************************************************************************/
+
+struct file_close_user_state {
+	uint64_t vuid;
+	bool fsp_left_behind;
+};
+
+static struct files_struct *file_close_user_fn(
+	struct files_struct *fsp,
+	void *private_data)
+{
+	struct file_close_user_state *state = private_data;
+	bool did_close;
+
+	if (fsp->vuid != state->vuid) {
+		return NULL;
+	}
+
+	did_close = close_file_in_loop(fsp, SHUTDOWN_CLOSE);
+	if (!did_close) {
+		state->fsp_left_behind = true;
+	}
+
+	return NULL;
+}
+
+void file_close_user(struct smbd_server_connection *sconn, uint64_t vuid)
+{
+	struct file_close_user_state state = { .vuid = vuid };
+
+	files_forall(sconn, file_close_user_fn, &state);
+
+	if (state.fsp_left_behind) {
+		state.fsp_left_behind = false;
+		files_forall(sconn, file_close_user_fn, &state);
+		SMB_ASSERT(!state.fsp_left_behind);
+	}
+}
+
+/*
+ * Walk the files table until "fn" returns non-NULL
+ */
+
+struct files_struct *files_forall(
+	struct smbd_server_connection *sconn,
+	struct files_struct *(*fn)(struct files_struct *fsp,
+				   void *private_data),
+	void *private_data)
+{
+	struct files_struct *fsp, *next;
+
+	for (fsp = sconn->files; fsp; fsp = next) {
+		struct files_struct *ret;
+		next = fsp->next;
+		ret = fn(fsp, private_data);
+		if (ret != NULL) {
+			return ret;
+		}
+	}
+	return NULL;
+}
+
+/****************************************************************************
+ Find a fsp given a file descriptor.
+****************************************************************************/
+
+files_struct *file_find_fd(struct smbd_server_connection *sconn, int fd)
+{
+	int count=0;
+	files_struct *fsp;
+
+	for (fsp=sconn->files; fsp; fsp=fsp->next,count++) {
+		if (fsp_get_pathref_fd(fsp) == fd) {
+			if (count > 10) {
+				DLIST_PROMOTE(sconn->files, fsp);
+			}
+			return fsp;
+		}
+	}
+
+	return NULL;
+}
+
+/****************************************************************************
+ Find a fsp given a device, inode and file_id.
+****************************************************************************/
+
+files_struct *file_find_dif(struct smbd_server_connection *sconn,
+			    struct file_id id, unsigned long gen_id)
+{
+	int count=0;
+	files_struct *fsp;
+
+	if (gen_id == 0) {
+		return NULL;
+	}
+
+	for (fsp = sconn->files; fsp; fsp = fsp->next,count++) {
+		/*
+		 * We can have a fsp->fh->fd == -1 here as it could be a stat
+		 * open.
+		 */
+		if (!file_id_equal(&fsp->file_id, &id)) {
+			continue;
+		}
+		if (!fsp->fsp_flags.is_fsa) {
+			continue;
+		}
+		if (fh_get_gen_id(fsp->fh) != gen_id) {
+			continue;
+		}
+		if (count > 10) {
+			DLIST_PROMOTE(sconn->files, fsp);
+		}
+		return fsp;
+	}
+
+	return NULL;
+}
+
+/****************************************************************************
+ Find the first fsp given a device and inode.
+ We use a singleton cache here to speed up searching from getfilepathinfo
+ calls.
+****************************************************************************/
+
+files_struct *file_find_di_first(struct smbd_server_connection *sconn,
+				 struct file_id id,
+				 bool need_fsa)
+{
+	files_struct *fsp;
+
+	if (file_id_equal(&sconn->fsp_fi_cache.id, &id)) {
+		/* Positive or negative cache hit. */
+		return sconn->fsp_fi_cache.fsp;
+	}
+
+	sconn->fsp_fi_cache.id = id;
+
+	for (fsp=sconn->files;fsp;fsp=fsp->next) {
+		if (need_fsa && !fsp->fsp_flags.is_fsa) {
+			continue;
+		}
+		if (file_id_equal(&fsp->file_id, &id)) {
+			/* Setup positive cache. */
+			sconn->fsp_fi_cache.fsp = fsp;
+			return fsp;
+		}
+	}
+
+	/* Setup negative cache. */
+	sconn->fsp_fi_cache.fsp = NULL;
+	return NULL;
+}
+
+/****************************************************************************
+ Find the next fsp having the same device and inode.
+****************************************************************************/
+
+files_struct *file_find_di_next(files_struct *start_fsp,
+				bool need_fsa)
+{
+	files_struct *fsp;
+
+	for (fsp = start_fsp->next;fsp;fsp=fsp->next) {
+		if (need_fsa && !fsp->fsp_flags.is_fsa) {
+			continue;
+		}
+		if (file_id_equal(&fsp->file_id, &start_fsp->file_id)) {
+			return fsp;
+		}
+	}
+
+	return NULL;
+}
+
+struct files_struct *file_find_one_fsp_from_lease_key(
+	struct smbd_server_connection *sconn,
+	const struct smb2_lease_key *lease_key)
+{
+	struct files_struct *fsp;
+
+	for (fsp = sconn->files; fsp; fsp=fsp->next) {
+		if ((fsp->lease != NULL) &&
+		    (fsp->lease->lease.lease_key.data[0] ==
+		     lease_key->data[0]) &&
+		    (fsp->lease->lease.lease_key.data[1] ==
+		     lease_key->data[1])) {
+			return fsp;
+		}
+	}
+	return NULL;
+}
+
+/****************************************************************************
+ Find any fsp open with a pathname below that of an already open path.
+****************************************************************************/
+
+bool file_find_subpath(files_struct *dir_fsp)
+{
+	files_struct *fsp;
+	size_t dlen;
+	char *d_fullname = NULL;
+
+	d_fullname = talloc_asprintf(talloc_tos(), "%s/%s",
+				     dir_fsp->conn->connectpath,
+				     dir_fsp->fsp_name->base_name);
+
+	if (!d_fullname) {
+		return false;
+	}
+
+	dlen = strlen(d_fullname);
+
+	for (fsp=dir_fsp->conn->sconn->files; fsp; fsp=fsp->next) {
+		char *d1_fullname;
+
+		if (fsp == dir_fsp) {
+			continue;
+		}
+
+		d1_fullname = talloc_asprintf(talloc_tos(),
+					"%s/%s",
+					fsp->conn->connectpath,
+					fsp->fsp_name->base_name);
+
+		/*
+		 * If the open file has a path that is a longer
+		 * component, then it's a subpath.
+		 */
+		if (strnequal(d_fullname, d1_fullname, dlen) &&
+				(d1_fullname[dlen] == '/')) {
+			TALLOC_FREE(d1_fullname);
+			TALLOC_FREE(d_fullname);
+			return true;
+		}
+		TALLOC_FREE(d1_fullname);
+	}
+
+	TALLOC_FREE(d_fullname);
+	return false;
+}
+
+/****************************************************************************
+ Free up a fsp.
+****************************************************************************/
+
+static void fsp_free(files_struct *fsp)
+{
+	struct smbd_server_connection *sconn = fsp->conn->sconn;
+
+	if (fsp == sconn->fsp_fi_cache.fsp) {
+		ZERO_STRUCT(sconn->fsp_fi_cache);
+	}
+
+	DLIST_REMOVE(sconn->files, fsp);
+	SMB_ASSERT(sconn->num_files > 0);
+	sconn->num_files--;
+
+	TALLOC_FREE(fsp->fake_file_handle);
+
+	if (fh_get_refcount(fsp->fh) == 1) {
+		TALLOC_FREE(fsp->fh);
+	} else {
+		size_t new_refcount = fh_get_refcount(fsp->fh) - 1;
+		fh_set_refcount(fsp->fh, new_refcount);
+	}
+
+	if (fsp->lease != NULL) {
+		if (fsp->lease->ref_count == 1) {
+			TALLOC_FREE(fsp->lease);
+		} else {
+			fsp->lease->ref_count--;
+		}
+	}
+
+	fsp->conn->num_files_open--;
+
+	if (fsp->fsp_name != NULL &&
+	    fsp->fsp_name->fsp_link != NULL)
+	{
+		/*
+		 * Free fsp_link of fsp->fsp_name. To do this in the correct
+		 * talloc destructor order we have to do it here. The
+		 * talloc_free() of the link should set the fsp pointer to NULL.
+		 */
+		TALLOC_FREE(fsp->fsp_name->fsp_link);
+		SMB_ASSERT(fsp->fsp_name->fsp == NULL);
+	}
+
+	/* this is paranoia, just in case someone tries to reuse the
+	   information */
+	ZERO_STRUCTP(fsp);
+
+	/* fsp->fsp_name is a talloc child and is free'd automatically. */
+	TALLOC_FREE(fsp);
+}
+
+/*
+ * Rundown of all smb-related sub-structures of an fsp
+ */
+void fsp_unbind_smb(struct smb_request *req, files_struct *fsp)
+{
+	if (fsp == fsp->conn->cwd_fsp) {
+		return;
+	}
+
+	if (fsp->notify) {
+		size_t len = fsp_fullbasepath(fsp, NULL, 0);
+		char fullpath[len+1];
+
+		fsp_fullbasepath(fsp, fullpath, sizeof(fullpath));
+
+		/*
+		 * Avoid /. at the end of the path name. notify can't
+		 * deal with it.
+		 */
+		if (len > 1 && fullpath[len-1] == '.' &&
+		    fullpath[len-2] == '/') {
+			fullpath[len-2] = '\0';
+		}
+
+		notify_remove(fsp->conn->sconn->notify_ctx, fsp, fullpath);
+		TALLOC_FREE(fsp->notify);
+	}
+
+	/* Ensure this event will never fire. */
+	TALLOC_FREE(fsp->update_write_time_event);
+
+	if (fsp->op != NULL) {
+		fsp->op->compat = NULL;
+	}
+	TALLOC_FREE(fsp->op);
+
+	if ((req != NULL) && (fsp == req->chain_fsp)) {
+		req->chain_fsp = NULL;
+	}
+
+	/*
+	 * Clear all possible chained fsp
+	 * pointers in the SMB2 request queue.
+	 */
+	remove_smb2_chained_fsp(fsp);
+}
+
+void file_free(struct smb_request *req, files_struct *fsp)
+{
+	struct smbd_server_connection *sconn = fsp->conn->sconn;
+	uint64_t fnum = fsp->fnum;
+
+	fsp_unbind_smb(req, fsp);
+
+	/* Drop all remaining extensions. */
+	vfs_remove_all_fsp_extensions(fsp);
+
+	fsp_free(fsp);
+
+	DBG_INFO("freed files structure %"PRIu64" (%zu used)\n",
+		 fnum,
+		 sconn->num_files);
+}
+
+/****************************************************************************
+ Get an fsp from a packet given a 16 bit fnum.
+****************************************************************************/
+
+files_struct *file_fsp(struct smb_request *req, uint16_t fid)
+{
+	struct smbXsrv_open *op;
+	NTSTATUS status;
+	NTTIME now = 0;
+	files_struct *fsp;
+
+	if (req == NULL) {
+		/*
+		 * We should never get here. req==NULL could in theory
+		 * only happen from internal opens with a non-zero
+		 * root_dir_fid. Internal opens just don't do that, at
+		 * least they are not supposed to do so. And if they
+		 * start to do so, they better fake up a smb_request
+		 * from which we get the right smbd_server_conn. While
+		 * this should never happen, let's return NULL here.
+		 */
+		return NULL;
+	}
+
+	if (req->chain_fsp != NULL) {
+		if (req->chain_fsp->fsp_flags.closing) {
+			return NULL;
+		}
+		return req->chain_fsp;
+	}
+
+	if (req->xconn == NULL) {
+		return NULL;
+	}
+
+	now = timeval_to_nttime(&req->request_time);
+
+	status = smb1srv_open_lookup(req->xconn,
+				     fid, now, &op);
+	if (!NT_STATUS_IS_OK(status)) {
+		return NULL;
+	}
+
+	fsp = op->compat;
+	if (fsp == NULL) {
+		return NULL;
+	}
+
+	if (fsp->fsp_flags.closing) {
+		return NULL;
+	}
+
+	req->chain_fsp = fsp;
+	fsp->fsp_name->st.cached_dos_attributes = FILE_ATTRIBUTE_INVALID;
+	return fsp;
+}
+
+struct files_struct *file_fsp_get(struct smbd_smb2_request *smb2req,
+				  uint64_t persistent_id,
+				  uint64_t volatile_id)
+{
+	struct smbXsrv_open *op;
+	NTSTATUS status;
+	NTTIME now = 0;
+	struct files_struct *fsp;
+
+	now = timeval_to_nttime(&smb2req->request_time);
+
+	status = smb2srv_open_lookup(smb2req->xconn,
+				     persistent_id, volatile_id,
+				     now, &op);
+	if (!NT_STATUS_IS_OK(status)) {
+		return NULL;
+	}
+
+	fsp = op->compat;
+	if (fsp == NULL) {
+		return NULL;
+	}
+
+	if (smb2req->tcon == NULL) {
+		return NULL;
+	}
+
+	if (smb2req->tcon->compat != fsp->conn) {
+		return NULL;
+	}
+
+	if (smb2req->session == NULL) {
+		return NULL;
+	}
+
+	if (smb2req->session->global->session_wire_id != fsp->vuid) {
+		return NULL;
+	}
+
+	if (fsp->fsp_flags.closing) {
+		return NULL;
+	}
+
+	fsp->fsp_name->st.cached_dos_attributes = FILE_ATTRIBUTE_INVALID;
+
+	return fsp;
+}
+
+struct files_struct *file_fsp_smb2(struct smbd_smb2_request *smb2req,
+				   uint64_t persistent_id,
+				   uint64_t volatile_id)
+{
+	struct files_struct *fsp;
+
+	if (smb2req->compat_chain_fsp != NULL) {
+		if (smb2req->compat_chain_fsp->fsp_flags.closing) {
+			return NULL;
+		}
+		smb2req->compat_chain_fsp->fsp_name->st.cached_dos_attributes =
+			FILE_ATTRIBUTE_INVALID;
+		return smb2req->compat_chain_fsp;
+	}
+
+	fsp = file_fsp_get(smb2req, persistent_id, volatile_id);
+	if (fsp == NULL) {
+		return NULL;
+	}
+
+	smb2req->compat_chain_fsp = fsp;
+	return fsp;
+}
+
+/****************************************************************************
+ Duplicate the file handle part for a DOS or FCB open.
+****************************************************************************/
+
+NTSTATUS dup_file_fsp(
+	files_struct *from,
+	uint32_t access_mask,
+	files_struct *to)
+{
+	size_t new_refcount;
+
+	/* this can never happen for print files */
+	SMB_ASSERT(from->print_file == NULL);
+
+	TALLOC_FREE(to->fh);
+
+	to->fh = from->fh;
+	new_refcount = fh_get_refcount(to->fh) + 1;
+	fh_set_refcount(to->fh, new_refcount);
+
+	to->file_id = from->file_id;
+	to->initial_allocation_size = from->initial_allocation_size;
+	to->file_pid = from->file_pid;
+	to->vuid = from->vuid;
+	to->open_time = from->open_time;
+	to->access_mask = access_mask;
+	to->oplock_type = from->oplock_type;
+	to->fsp_flags.can_lock = from->fsp_flags.can_lock;
+	to->fsp_flags.can_read = ((access_mask & FILE_READ_DATA) != 0);
+	to->fsp_flags.can_write =
+		CAN_WRITE(from->conn) &&
+		((access_mask & (FILE_WRITE_DATA | FILE_APPEND_DATA)) != 0);
+	if (from->fsp_name->twrp != 0) {
+		to->fsp_flags.can_write = false;
+	}
+	to->fsp_flags.modified = from->fsp_flags.modified;
+	to->fsp_flags.is_directory = from->fsp_flags.is_directory;
+	to->fsp_flags.aio_write_behind = from->fsp_flags.aio_write_behind;
+	to->fsp_flags.is_fsa = from->fsp_flags.is_fsa;
+	to->fsp_flags.is_pathref = from->fsp_flags.is_pathref;
+	to->fsp_flags.have_proc_fds = from->fsp_flags.have_proc_fds;
+	to->fsp_flags.is_dirfsp = from->fsp_flags.is_dirfsp;
+
+	return fsp_set_smb_fname(to, from->fsp_name);
+}
+
+/**
+ * Return a jenkins hash of a pathname on a connection.
+ */
+
+NTSTATUS file_name_hash(connection_struct *conn,
+			const char *name, uint32_t *p_name_hash)
+{
+	char tmpbuf[PATH_MAX];
+	char *fullpath, *to_free;
+	ssize_t len;
+	TDB_DATA key;
+
+	/* Set the hash of the full pathname. */
+
+	if (name[0] == '/') {
+		strlcpy(tmpbuf, name, sizeof(tmpbuf));
+		fullpath = tmpbuf;
+		len = strlen(fullpath);
+		to_free = NULL;
+	} else {
+		len = full_path_tos(conn->connectpath,
+				    name,
+				    tmpbuf,
+				    sizeof(tmpbuf),
+				    &fullpath,
+				    &to_free);
+	}
+	if (len == -1) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	key = (TDB_DATA) { .dptr = (uint8_t *)fullpath, .dsize = len+1 };
+	*p_name_hash = tdb_jenkins_hash(&key);
+
+	DEBUG(10,("file_name_hash: %s hash 0x%x\n",
+		  fullpath,
+		(unsigned int)*p_name_hash ));
+
+	TALLOC_FREE(to_free);
+	return NT_STATUS_OK;
+}
+
+static NTSTATUS fsp_attach_smb_fname(struct files_struct *fsp,
+				     struct smb_filename **_smb_fname)
+{
+	TALLOC_CTX *frame = talloc_stackframe();
+	struct smb_filename *smb_fname_new = talloc_move(fsp, _smb_fname);
+	const char *name_str = NULL;
+	uint32_t name_hash = 0;
+	NTSTATUS status;
+
+	name_str = smb_fname_str_dbg(smb_fname_new);
+	if (name_str == NULL) {
+		TALLOC_FREE(frame);
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = file_name_hash(fsp->conn,
+				name_str,
+				&name_hash);
+	TALLOC_FREE(frame);
+	name_str = NULL;
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	status = fsp_smb_fname_link(fsp,
+				    &smb_fname_new->fsp_link,
+				    &smb_fname_new->fsp);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	fsp->name_hash = name_hash;
+	fsp->fsp_name = smb_fname_new;
+	fsp->fsp_name->st.cached_dos_attributes = FILE_ATTRIBUTE_INVALID;
+	*_smb_fname = NULL;
+	return NT_STATUS_OK;
+}
+
+/**
+ * The only way that the fsp->fsp_name field should ever be set.
+ */
+NTSTATUS fsp_set_smb_fname(struct files_struct *fsp,
+			   const struct smb_filename *smb_fname_in)
+{
+	struct smb_filename *smb_fname_old = fsp->fsp_name;
+	struct smb_filename *smb_fname_new = NULL;
+	NTSTATUS status;
+
+	smb_fname_new = cp_smb_filename(fsp, smb_fname_in);
+	if (smb_fname_new == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = fsp_attach_smb_fname(fsp, &smb_fname_new);
+	if (!NT_STATUS_IS_OK(status)) {
+		TALLOC_FREE(smb_fname_new);
+		return status;
+	}
+
+	if (smb_fname_old != NULL) {
+		smb_fname_fsp_unlink(smb_fname_old);
+		TALLOC_FREE(smb_fname_old);
+	}
+
+	return NT_STATUS_OK;
+}
+
+size_t fsp_fullbasepath(struct files_struct *fsp, char *buf, size_t buflen)
+{
+	int len = 0;
+
+	if ((buf == NULL) || (buflen == 0)) {
+		return strlen(fsp->conn->connectpath) + 1 +
+		       strlen(fsp->fsp_name->base_name);
+	}
+
+	len = snprintf(buf, buflen, "%s/%s", fsp->conn->connectpath,
+		       fsp->fsp_name->base_name);
+	SMB_ASSERT(len>0);
+
+	return len;
+}
+
+void fsp_set_base_fsp(struct files_struct *fsp, struct files_struct *base_fsp)
+{
+	SMB_ASSERT(fsp->stream_fsp == NULL);
+	if (base_fsp != NULL) {
+		SMB_ASSERT(base_fsp->base_fsp == NULL);
+		SMB_ASSERT(base_fsp->stream_fsp == NULL);
+	}
+
+	if (fsp->base_fsp != NULL) {
+		SMB_ASSERT(fsp->base_fsp->stream_fsp == fsp);
+		fsp->base_fsp->stream_fsp = NULL;
+	}
+
+	fsp->base_fsp = base_fsp;
+	if (fsp->base_fsp != NULL) {
+		fsp->base_fsp->stream_fsp = fsp;
+	}
+}
+
+bool fsp_is_alternate_stream(const struct files_struct *fsp)
+{
+	return (fsp->base_fsp != NULL);
+}
+
+struct files_struct *metadata_fsp(struct files_struct *fsp)
+{
+	if (fsp_is_alternate_stream(fsp)) {
+		return fsp->base_fsp;
+	}
+	return fsp;
+}
+
+static bool fsp_generic_ask_sharemode(struct files_struct *fsp)
+{
+	if (fsp == NULL) {
+		return false;
+	}
+
+	if (fsp->posix_flags & FSP_POSIX_FLAGS_PATHNAMES) {
+		/* Always use filesystem for UNIX mtime query. */
+		return false;
+	}
+
+	return true;
+}
+
+bool fsp_search_ask_sharemode(struct files_struct *fsp)
+{
+	if (!fsp_generic_ask_sharemode(fsp)) {
+		return false;
+	}
+
+	return lp_smbd_search_ask_sharemode(SNUM(fsp->conn));
+}
+
+bool fsp_getinfo_ask_sharemode(struct files_struct *fsp)
+{
+	if (!fsp_generic_ask_sharemode(fsp)) {
+		return false;
+	}
+
+	return lp_smbd_getinfo_ask_sharemode(SNUM(fsp->conn));
+}