s3-xattr_tdb: make xattr_tdb a private library, for use outside vfs_xattr_tdb

2 files changed, 495 insertions, 0 deletions

diff --git a/source3/lib/xattr_tdb.c b/source3/lib/xattr_tdb.c
new file mode 100644
index 0000000000..21223f04b8
--- /dev/null
+++ b/source3/lib/xattr_tdb.c
@@ -0,0 +1,455 @@
+/*
+ * Store posix-level xattrs in a tdb
+ *
+ * Copyright (C) Andrew Bartlett 2011
+ *
+ * extracted from vfs_xattr_tdb by
+ *
+ * Copyright (C) Volker Lendecke, 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"
+#include "system/filesys.h"
+#include "librpc/gen_ndr/xattr.h"
+#include "librpc/gen_ndr/ndr_xattr.h"
+#include "librpc/gen_ndr/file_id.h"
+#include "dbwrap/dbwrap.h"
+#include "lib/util/util_tdb.h"
+#include "source3/lib/xattr_tdb.h"
+#include "source3/lib/file_id.h"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_VFS
+
+/*
+ * unmarshall tdb_xattrs
+ */
+
+static NTSTATUS xattr_tdb_pull_attrs(TALLOC_CTX *mem_ctx,
+				     const TDB_DATA *data,
+				     struct tdb_xattrs **presult)
+{
+	DATA_BLOB blob;
+	enum ndr_err_code ndr_err;
+	struct tdb_xattrs *result;
+
+	if (!(result = talloc_zero(mem_ctx, struct tdb_xattrs))) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	if (data->dsize == 0) {
+		*presult = result;
+		return NT_STATUS_OK;
+	}
+
+	blob = data_blob_const(data->dptr, data->dsize);
+
+	ndr_err = ndr_pull_struct_blob(&blob, result, result,
+		(ndr_pull_flags_fn_t)ndr_pull_tdb_xattrs);
+
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		DEBUG(0, ("ndr_pull_tdb_xattrs failed: %s\n",
+			  ndr_errstr(ndr_err)));
+		TALLOC_FREE(result);
+		return ndr_map_error2ntstatus(ndr_err);
+	}
+
+	*presult = result;
+	return NT_STATUS_OK;
+}
+
+/*
+ * marshall tdb_xattrs
+ */
+
+static NTSTATUS xattr_tdb_push_attrs(TALLOC_CTX *mem_ctx,
+				     const struct tdb_xattrs *attribs,
+				     TDB_DATA *data)
+{
+	DATA_BLOB blob;
+	enum ndr_err_code ndr_err;
+
+	ndr_err = ndr_push_struct_blob(&blob, mem_ctx, attribs,
+		(ndr_push_flags_fn_t)ndr_push_tdb_xattrs);
+
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		DEBUG(0, ("ndr_push_tdb_xattrs failed: %s\n",
+			  ndr_errstr(ndr_err)));
+		return ndr_map_error2ntstatus(ndr_err);
+	}
+
+	*data = make_tdb_data(blob.data, blob.length);
+	return NT_STATUS_OK;
+}
+
+/*
+ * Load tdb_xattrs for a file from the tdb
+ */
+
+static NTSTATUS xattr_tdb_load_attrs(TALLOC_CTX *mem_ctx,
+				     struct db_context *db_ctx,
+				     const struct file_id *id,
+				     struct tdb_xattrs **presult)
+{
+	uint8_t id_buf[16];
+	NTSTATUS status;
+	TDB_DATA data;
+
+	/* For backwards compatibility only store the dev/inode. */
+	push_file_id_16((char *)id_buf, id);
+
+	status = dbwrap_fetch(db_ctx, mem_ctx,
+			      make_tdb_data(id_buf, sizeof(id_buf)),
+			      &data);
+	if (!NT_STATUS_IS_OK(status)) {
+		return NT_STATUS_INTERNAL_DB_CORRUPTION;
+	}
+
+	status = xattr_tdb_pull_attrs(mem_ctx, &data, presult);
+	TALLOC_FREE(data.dptr);
+	return status;
+}
+
+/*
+ * fetch_lock the tdb_ea record for a file
+ */
+
+static struct db_record *xattr_tdb_lock_attrs(TALLOC_CTX *mem_ctx,
+					      struct db_context *db_ctx,
+					      const struct file_id *id)
+{
+	uint8_t id_buf[16];
+
+	/* For backwards compatibility only store the dev/inode. */
+	push_file_id_16((char *)id_buf, id);
+	return dbwrap_fetch_locked(db_ctx, mem_ctx,
+				   make_tdb_data(id_buf, sizeof(id_buf)));
+}
+
+/*
+ * Save tdb_xattrs to a previously fetch_locked record
+ */
+
+static NTSTATUS xattr_tdb_save_attrs(struct db_record *rec,
+				     const struct tdb_xattrs *attribs)
+{
+	TDB_DATA data = tdb_null;
+	NTSTATUS status;
+
+	status = xattr_tdb_push_attrs(talloc_tos(), attribs, &data);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(0, ("xattr_tdb_push_attrs failed: %s\n",
+			  nt_errstr(status)));
+		return status;
+	}
+
+	status = dbwrap_record_store(rec, data, 0);
+
+	TALLOC_FREE(data.dptr);
+
+	return status;
+}
+
+/*
+ * Worker routine for getxattr and fgetxattr
+ */
+
+ssize_t xattr_tdb_getattr(struct db_context *db_ctx,
+			  const struct file_id *id,
+			  const char *name, void *value, size_t size)
+{
+	struct tdb_xattrs *attribs;
+	uint32_t i;
+	ssize_t result = -1;
+	NTSTATUS status;
+
+	DEBUG(10, ("xattr_tdb_getattr called for file %s, name %s\n",
+		   file_id_string_tos(id), name));
+
+	status = xattr_tdb_load_attrs(talloc_tos(), db_ctx, id, &attribs);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("xattr_tdb_fetch_attrs failed: %s\n",
+			   nt_errstr(status)));
+		errno = EINVAL;
+		return -1;
+	}
+
+	for (i=0; i<attribs->num_eas; i++) {
+		if (strcmp(attribs->eas[i].name, name) == 0) {
+			break;
+		}
+	}
+
+	if (i == attribs->num_eas) {
+		errno = ENOATTR;
+		goto fail;
+	}
+
+	if (attribs->eas[i].value.length > size) {
+		errno = ERANGE;
+		goto fail;
+	}
+
+	memcpy(value, attribs->eas[i].value.data,
+	       attribs->eas[i].value.length);
+	result = attribs->eas[i].value.length;
+
+ fail:
+	TALLOC_FREE(attribs);
+	return result;
+}
+
+/*
+ * Worker routine for setxattr and fsetxattr
+ */
+
+int xattr_tdb_setattr(struct db_context *db_ctx,
+		      const struct file_id *id, const char *name,
+		      const void *value, size_t size, int flags)
+{
+	NTSTATUS status;
+	struct db_record *rec;
+	struct tdb_xattrs *attribs;
+	uint32_t i;
+	TDB_DATA data;
+
+	DEBUG(10, ("xattr_tdb_setattr called for file %s, name %s\n",
+		   file_id_string_tos(id), name));
+
+	rec = xattr_tdb_lock_attrs(talloc_tos(), db_ctx, id);
+
+	if (rec == NULL) {
+		DEBUG(0, ("xattr_tdb_lock_attrs failed\n"));
+		errno = EINVAL;
+		return -1;
+	}
+
+	data = dbwrap_record_get_value(rec);
+
+	status = xattr_tdb_pull_attrs(rec, &data, &attribs);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("xattr_tdb_fetch_attrs failed: %s\n",
+			   nt_errstr(status)));
+		TALLOC_FREE(rec);
+		return -1;
+	}
+
+	for (i=0; i<attribs->num_eas; i++) {
+		if (strcmp(attribs->eas[i].name, name) == 0) {
+			if (flags & XATTR_CREATE) {
+				TALLOC_FREE(rec);
+				errno = EEXIST;
+				return -1;
+			}
+			break;
+		}
+	}
+
+	if (i == attribs->num_eas) {
+		struct xattr_EA *tmp;
+
+		if (flags & XATTR_REPLACE) {
+			TALLOC_FREE(rec);
+			errno = ENOATTR;
+			return -1;
+		}
+
+		tmp = talloc_realloc(
+			attribs, attribs->eas, struct xattr_EA,
+			attribs->num_eas+ 1);
+
+		if (tmp == NULL) {
+			DEBUG(0, ("talloc_realloc failed\n"));
+			TALLOC_FREE(rec);
+			errno = ENOMEM;
+			return -1;
+		}
+
+		attribs->eas = tmp;
+		attribs->num_eas += 1;
+	}
+
+	attribs->eas[i].name = name;
+	attribs->eas[i].value.data = discard_const_p(uint8_t, value);
+	attribs->eas[i].value.length = size;
+
+	status = xattr_tdb_save_attrs(rec, attribs);
+
+	TALLOC_FREE(rec);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(1, ("save failed: %s\n", nt_errstr(status)));
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Worker routine for listxattr and flistxattr
+ */
+
+ssize_t xattr_tdb_listattr(struct db_context *db_ctx,
+			   const struct file_id *id, char *list,
+			   size_t size)
+{
+	NTSTATUS status;
+	struct tdb_xattrs *attribs;
+	uint32_t i;
+	size_t len = 0;
+
+	status = xattr_tdb_load_attrs(talloc_tos(), db_ctx, id, &attribs);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("xattr_tdb_fetch_attrs failed: %s\n",
+			   nt_errstr(status)));
+		errno = EINVAL;
+		return -1;
+	}
+
+	DEBUG(10, ("xattr_tdb_listattr: Found %d xattrs\n",
+		   attribs->num_eas));
+
+	for (i=0; i<attribs->num_eas; i++) {
+		size_t tmp;
+
+		DEBUG(10, ("xattr_tdb_listattr: xattrs[i].name: %s\n",
+			   attribs->eas[i].name));
+
+		tmp = strlen(attribs->eas[i].name);
+
+		/*
+		 * Try to protect against overflow
+		 */
+
+		if (len + (tmp+1) < len) {
+			TALLOC_FREE(attribs);
+			errno = EINVAL;
+			return -1;
+		}
+
+		/*
+		 * Take care of the terminating NULL
+		 */
+		len += (tmp + 1);
+	}
+
+	if (len > size) {
+		TALLOC_FREE(attribs);
+		errno = ERANGE;
+		return len;
+	}
+
+	len = 0;
+
+	for (i=0; i<attribs->num_eas; i++) {
+		strlcpy(list+len, attribs->eas[i].name,
+			size-len);
+		len += (strlen(attribs->eas[i].name) + 1);
+	}
+
+	TALLOC_FREE(attribs);
+	return len;
+}
+
+/*
+ * Worker routine for removexattr and fremovexattr
+ */
+
+int xattr_tdb_removeattr(struct db_context *db_ctx,
+			 const struct file_id *id, const char *name)
+{
+	NTSTATUS status;
+	struct db_record *rec;
+	struct tdb_xattrs *attribs;
+	uint32_t i;
+	TDB_DATA value;
+
+	rec = xattr_tdb_lock_attrs(talloc_tos(), db_ctx, id);
+
+	if (rec == NULL) {
+		DEBUG(0, ("xattr_tdb_lock_attrs failed\n"));
+		errno = EINVAL;
+		return -1;
+	}
+
+	value = dbwrap_record_get_value(rec);
+
+	status = xattr_tdb_pull_attrs(rec, &value, &attribs);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("xattr_tdb_fetch_attrs failed: %s\n",
+			   nt_errstr(status)));
+		TALLOC_FREE(rec);
+		return -1;
+	}
+
+	for (i=0; i<attribs->num_eas; i++) {
+		if (strcmp(attribs->eas[i].name, name) == 0) {
+			break;
+		}
+	}
+
+	if (i == attribs->num_eas) {
+		TALLOC_FREE(rec);
+		errno = ENOATTR;
+		return -1;
+	}
+
+	attribs->eas[i] =
+		attribs->eas[attribs->num_eas-1];
+	attribs->num_eas -= 1;
+
+	if (attribs->num_eas == 0) {
+		dbwrap_record_delete(rec);
+		TALLOC_FREE(rec);
+		return 0;
+	}
+
+	status = xattr_tdb_save_attrs(rec, attribs);
+
+	TALLOC_FREE(rec);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(1, ("save failed: %s\n", nt_errstr(status)));
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Worker routine for unlink and rmdir
+ */
+
+void xattr_tdb_remove_all_attrs(struct db_context *db_ctx,
+			       const struct file_id *id)
+{
+	struct db_record *rec;
+	rec = xattr_tdb_lock_attrs(talloc_tos(), db_ctx, id);
+
+	/*
+	 * If rec == NULL there's not much we can do about it
+	 */
+
+	if (rec != NULL) {
+		dbwrap_record_delete(rec);
+		TALLOC_FREE(rec);
+	}
+}
diff --git a/source3/lib/xattr_tdb.h b/source3/lib/xattr_tdb.h
new file mode 100644
index 0000000000..0a54833f51
--- /dev/null
+++ b/source3/lib/xattr_tdb.h
@@ -0,0 +1,40 @@
+/*
+ * Store posix-level xattrs in a tdb
+ *
+ * Copyright (C) Andrew Bartlett 2011
+ *
+ * extracted from vfs_xattr_tdb by
+ *
+ * Copyright (C) Volker Lendecke, 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 "librpc/gen_ndr/file_id.h"
+
+/* The following definitions come from lib/util/xattr_tdb.c  */
+
+ssize_t xattr_tdb_getattr(struct db_context *db_ctx,
+			  const struct file_id *id,
+			  const char *name, void *value, size_t size);
+int xattr_tdb_setattr(struct db_context *db_ctx,
+		      const struct file_id *id, const char *name,
+		      const void *value, size_t size, int flags);
+ssize_t xattr_tdb_listattr(struct db_context *db_ctx,
+			   const struct file_id *id, char *list,
+			   size_t size);
+int xattr_tdb_removeattr(struct db_context *db_ctx,
+			 const struct file_id *id, const char *name);
+void xattr_tdb_remove_all_attrs(struct db_context *db_ctx,
+				const struct file_id *id);