diff --git a/source3/modules/string_replace.c b/source3/modules/string_replace.c
new file mode 100644
index 00000000000..88b53fbbf4a
--- /dev/null
+++ b/source3/modules/string_replace.c
@@ -0,0 +1,178 @@
+/*
+ * Unix SMB/CIFS implementation.
+ *
+ * Copyright (C) Volker Lendecke, 2005
+ * Copyright (C) Aravind Srinivasan, 2009
+ * Copyright (C) Guenter Kukkukk, 2013
+ * Copyright (C) Ralph Boehme, 2017
+ *
+ * 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 "string_replace.h"
+
+#define MAP_SIZE        0xFF
+#define MAP_NUM         0x101 /* max unicode charval / MAP_SIZE */
+#define T_OFFSET(_v_)   ((_v_ % MAP_SIZE))
+#define T_START(_v_)    (((_v_ / MAP_SIZE) * MAP_SIZE))
+#define T_PICK(_v_)     ((_v_ / MAP_SIZE))
+
+struct char_mappings {
+	smb_ucs2_t entry[MAP_SIZE][2];
+};
+
+static bool build_table(struct char_mappings **cmaps, int value)
+{
+	int i;
+	int start = T_START(value);
+
+	(*cmaps) = talloc_zero(NULL, struct char_mappings);
+
+	if (!*cmaps)
+		return False;
+
+	for (i = 0; i < MAP_SIZE;i++) {
+		(*cmaps)->entry[i][vfs_translate_to_unix] = start + i;
+		(*cmaps)->entry[i][vfs_translate_to_windows] = start + i;
+	}
+
+	return True;
+}
+
+static void set_tables(struct char_mappings **cmaps,
+		       long unix_map,
+		       long windows_map)
+{
+	int i;
+
+	/* set unix -> windows */
+	i = T_OFFSET(unix_map);
+	cmaps[T_PICK(unix_map)]->entry[i][vfs_translate_to_windows] = windows_map;
+
+	/* set windows -> unix */
+	i = T_OFFSET(windows_map);
+	cmaps[T_PICK(windows_map)]->entry[i][vfs_translate_to_unix] = unix_map;
+}
+
+static bool build_ranges(struct char_mappings **cmaps,
+			 long unix_map,
+			 long windows_map)
+{
+
+	if (!cmaps[T_PICK(unix_map)]) {
+		if (!build_table(&cmaps[T_PICK(unix_map)], unix_map))
+			return False;
+	}
+
+	if (!cmaps[T_PICK(windows_map)]) {
+		if (!build_table(&cmaps[T_PICK(windows_map)], windows_map))
+			return False;
+	}
+
+	set_tables(cmaps, unix_map, windows_map);
+
+	return True;
+}
+
+struct char_mappings **string_replace_init_map(const char **mappings)
+{
+	int i;
+	char *tmp;
+	fstring mapping;
+	long unix_map, windows_map;
+	struct char_mappings **cmaps = NULL;
+
+	if (mappings == NULL) {
+		return NULL;
+	}
+
+	cmaps = TALLOC_ZERO(NULL, MAP_NUM * sizeof(struct char_mappings *));
+	if (cmaps == NULL) {
+		return NULL;
+	}
+
+	/*
+	 * catia mappings are of the form :
+	 * UNIX char (in 0xnn hex) : WINDOWS char (in 0xnn hex)
+	 *
+	 * multiple mappings are comma separated in smb.conf
+	 */
+
+	for (i = 0; mappings[i]; i++) {
+		fstrcpy(mapping, mappings[i]);
+		unix_map = strtol(mapping, &tmp, 16);
+		if (unix_map == 0 && errno == EINVAL) {
+			DEBUG(0, ("INVALID CATIA MAPPINGS - %s\n", mapping));
+			continue;
+		}
+		windows_map = strtol(++tmp, NULL, 16);
+		if (windows_map == 0 && errno == EINVAL) {
+			DEBUG(0, ("INVALID CATIA MAPPINGS - %s\n", mapping));
+			continue;
+		}
+
+		if (!build_ranges(cmaps, unix_map, windows_map)) {
+			DEBUG(0, ("TABLE ERROR - CATIA MAPPINGS - %s\n", mapping));
+			continue;
+		}
+	}
+
+	return cmaps;
+}
+
+NTSTATUS string_replace_allocate(connection_struct *conn,
+				 const char *name_in,
+				 struct char_mappings **cmaps,
+				 TALLOC_CTX *mem_ctx,
+				 char **mapped_name,
+				 enum vfs_translate_direction direction)
+{
+	static smb_ucs2_t *tmpbuf = NULL;
+	smb_ucs2_t *ptr = NULL;
+	struct char_mappings *map = NULL;
+	size_t converted_size;
+	bool ok;
+
+	ok = push_ucs2_talloc(talloc_tos(), &tmpbuf, name_in,
+			      &converted_size);
+	if (!ok) {
+		return map_nt_error_from_unix(errno);
+	}
+
+	for (ptr = tmpbuf; *ptr; ptr++) {
+		if (*ptr == 0) {
+			break;
+		}
+		if (cmaps == NULL) {
+			continue;
+		}
+		map = cmaps[T_PICK((*ptr))];
+		if (map == NULL) {
+			/* nothing to do */
+			continue;
+		}
+
+		*ptr = map->entry[T_OFFSET((*ptr))][direction];
+	}
+
+	ok = pull_ucs2_talloc(mem_ctx, mapped_name, tmpbuf,
+			      &converted_size);
+	TALLOC_FREE(tmpbuf);
+	if (!ok) {
+		return map_nt_error_from_unix(errno);
+	}
+	return NT_STATUS_OK;
+}
diff --git a/source3/modules/string_replace.h b/source3/modules/string_replace.h
new file mode 100644
index 00000000000..d7c9b52c85c
--- /dev/null
+++ b/source3/modules/string_replace.h
@@ -0,0 +1,32 @@
+/*
+ * Unix SMB/CIFS implementation.
+ *
+ * Copyright (C) Volker Lendecke, 2005
+ * Copyright (C) Aravind Srinivasan, 2009
+ * Copyright (C) Guenter Kukkukk, 2013
+ * Copyright (C) Ralph Boehme, 2017
+ *
+ * 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/>.
+ */
+
+struct char_mappings;
+
+struct char_mappings **string_replace_init_map(const char **mappings);
+
+NTSTATUS string_replace_allocate(connection_struct *conn,
+				 const char *name_in,
+				 struct char_mappings **cmaps,
+				 TALLOC_CTX *mem_ctx,
+				 char **mapped_name,
+				 enum vfs_translate_direction direction);
diff --git a/source3/modules/vfs_catia.c b/source3/modules/vfs_catia.c
index c47b64d8657..ce760ceefda 100644
--- a/source3/modules/vfs_catia.c
+++ b/source3/modules/vfs_catia.c
@@ -31,23 +31,13 @@
 #include "smbd/smbd.h"
 #include "lib/util/tevent_unix.h"
 #include "lib/util/tevent_ntstatus.h"
+#include "string_replace.h"
 
 static int vfs_catia_debug_level = DBGC_VFS;
 
 #undef DBGC_CLASS
 #define DBGC_CLASS vfs_catia_debug_level
 
-#define GLOBAL_SNUM     0xFFFFFFF
-#define MAP_SIZE        0xFF
-#define MAP_NUM         0x101 /* max unicode charval / MAP_SIZE */
-#define T_OFFSET(_v_)   ((_v_ % MAP_SIZE))
-#define T_START(_v_)    (((_v_ / MAP_SIZE) * MAP_SIZE))
-#define T_PICK(_v_)     ((_v_ / MAP_SIZE))
-
-struct char_mappings {
-	smb_ucs2_t entry[MAP_SIZE][2];
-};
-
 struct share_mapping_entry {
 	int snum;
 	struct share_mapping_entry *next;
@@ -65,66 +55,13 @@ struct catia_cache {
 
 struct share_mapping_entry *srt_head = NULL;
 
-static bool build_table(struct char_mappings **cmaps, int value)
-{
-	int i;
-	int start = T_START(value);
-
-	(*cmaps) = talloc_zero(NULL, struct char_mappings);
-
-	if (!*cmaps)
-		return False;
-
-	for (i = 0; i < MAP_SIZE;i++) {
-		(*cmaps)->entry[i][vfs_translate_to_unix] = start + i;
-		(*cmaps)->entry[i][vfs_translate_to_windows] = start + i;
-	}
-
-	return True;
-}
-
-static void set_tables(struct char_mappings **cmaps,
-		       long unix_map,
-		       long windows_map)
-{
-	int i;
-
-	/* set unix -> windows */
-	i = T_OFFSET(unix_map);
-	cmaps[T_PICK(unix_map)]->entry[i][vfs_translate_to_windows] = windows_map;
-
-	/* set windows -> unix */
-	i = T_OFFSET(windows_map);
-	cmaps[T_PICK(windows_map)]->entry[i][vfs_translate_to_unix] = unix_map;
-}
-
-static bool build_ranges(struct char_mappings **cmaps,
-			 long unix_map,
-			 long windows_map)
-{
-
-	if (!cmaps[T_PICK(unix_map)]) {
-		if (!build_table(&cmaps[T_PICK(unix_map)], unix_map))
-			return False;
-	}
-
-	if (!cmaps[T_PICK(windows_map)]) {
-		if (!build_table(&cmaps[T_PICK(windows_map)], windows_map))
-			return False;
-	}
-
-	set_tables(cmaps, unix_map, windows_map);
-
-	return True;
-}
-
 static struct share_mapping_entry *get_srt(connection_struct *conn,
 					   struct share_mapping_entry **global)
 {
 	struct share_mapping_entry *share;
 
 	for (share = srt_head; share != NULL; share = share->next) {
-		if (share->snum == GLOBAL_SNUM)
+		if (share->snum == GLOBAL_SECTION_SNUM)
 			(*global) = share;
 
 		if (share->snum == SNUM(conn))
@@ -136,61 +73,24 @@ static struct share_mapping_entry *get_srt(connection_struct *conn,
 
 static struct share_mapping_entry *add_srt(int snum, const char **mappings)
 {
+	struct share_mapping_entry *sme = NULL;
 
-	char *tmp;
-	fstring mapping;
-	int i;
-	long unix_map, windows_map;
-	struct share_mapping_entry *ret = NULL;
+	sme = TALLOC_ZERO(NULL, sizeof(struct share_mapping_entry));
+	if (sme == NULL)
+		return sme;
 
-	ret = (struct share_mapping_entry *)
-		TALLOC_ZERO(NULL, sizeof(struct share_mapping_entry) +
-		(mappings ? (MAP_NUM * sizeof(struct char_mappings *)) : 0));
+	sme->snum = snum;
+	sme->next = srt_head;
+	srt_head = sme;
 
-	if (!ret)
-		return ret;
-
-	ret->snum = snum;
-
-	ret->next = srt_head;
-	srt_head = ret;
-
-	if (mappings) {
-		ret->mappings = (struct char_mappings**) ((unsigned char*) ret +
-		    sizeof(struct share_mapping_entry));
-		memset(ret->mappings, 0,
-		    MAP_NUM * sizeof(struct char_mappings *));
-	} else {
-		ret->mappings = NULL;
-		return ret;
+	if (mappings == NULL) {
+		sme->mappings = NULL;
+		return sme;
 	}
 
-	/*
-	 * catia mappings are of the form :
-	 * UNIX char (in 0xnn hex) : WINDOWS char (in 0xnn hex)
-	 *
-	 * multiple mappings are comma separated in smb.conf
-	 */
-	for (i=0;mappings[i];i++) {
-		fstrcpy(mapping, mappings[i]);
-		unix_map = strtol(mapping, &tmp, 16);
-		if (unix_map == 0 && errno == EINVAL) {
-			DEBUG(0, ("INVALID CATIA MAPPINGS - %s\n", mapping));
-			continue;
-		}
-		windows_map = strtol(++tmp, NULL, 16);
-		if (windows_map == 0 && errno == EINVAL) {
-			DEBUG(0, ("INVALID CATIA MAPPINGS - %s\n", mapping));
-			continue;
-		}
+	sme->mappings = string_replace_init_map(mappings);
 
-		if (!build_ranges(ret->mappings, unix_map, windows_map)) {
-			DEBUG(0, ("TABLE ERROR - CATIA MAPPINGS - %s\n", mapping));
-			continue;
-		}
-	}
-
-	return ret;
+	return sme;
 }
 
 static bool init_mappings(connection_struct *conn,
@@ -211,7 +111,7 @@ static bool init_mappings(connection_struct *conn,
 	if (!global) {
 		/* global setting */
 		mappings = lp_parm_string_list(-1, "catia", "mappings", NULL);
-		global = add_srt(GLOBAL_SNUM, mappings);
+		global = add_srt(GLOBAL_SECTION_SNUM, mappings);
 	}
 
 	/* no global setting - what about share level ? */
@@ -236,12 +136,8 @@ static NTSTATUS catia_string_replace_allocate(connection_struct *conn,
 					      char **mapped_name,
 					enum vfs_translate_direction direction)
 {
-	static smb_ucs2_t *tmpbuf = NULL;
-	smb_ucs2_t *ptr;
 	struct share_mapping_entry *selected;
-	struct char_mappings *map = NULL;
-	size_t converted_size;
-	TALLOC_CTX *ctx = talloc_tos();
+	NTSTATUS status;
 
 	if (!init_mappings(conn, &selected)) {
 		/* No mappings found. Just use the old name */
@@ -253,30 +149,13 @@ static NTSTATUS catia_string_replace_allocate(connection_struct *conn,
 		return NT_STATUS_OK;
 	}
 
-	if ((push_ucs2_talloc(ctx, &tmpbuf, name_in,
-			      &converted_size)) == false) {
-		return map_nt_error_from_unix(errno);
-	}
-	ptr = tmpbuf;
-	for(;*ptr;ptr++) {
-		if (*ptr == 0)
-			break;
-		map = selected->mappings[T_PICK((*ptr))];
-
-		/* nothing to do */
-		if (!map)
-			continue;
-
-		*ptr = map->entry[T_OFFSET((*ptr))][direction];
-	}
-
-	if ((pull_ucs2_talloc(ctx, mapped_name, tmpbuf,
-			      &converted_size)) == false) {
-		TALLOC_FREE(tmpbuf);
-		return map_nt_error_from_unix(errno);
-	}
-	TALLOC_FREE(tmpbuf);
-	return NT_STATUS_OK;
+	status = string_replace_allocate(conn,
+					 name_in,
+					 selected->mappings,
+					 talloc_tos(),
+					 mapped_name,
+					 direction);
+	return status;
 }
 
 static DIR *catia_opendir(vfs_handle_struct *handle,
diff --git a/source3/modules/wscript_build b/source3/modules/wscript_build
index 58aaf2e99d9..810dc4cd6be 100644
--- a/source3/modules/wscript_build
+++ b/source3/modules/wscript_build
@@ -29,6 +29,9 @@ bld.SAMBA3_SUBSYSTEM('OFFLOAD_TOKEN',
                     source='offload_token.c',
                     deps='samba-util')
 
+bld.SAMBA3_SUBSYSTEM('STRING_REPLACE',
+                    source='string_replace.c')
+
 bld.SAMBA3_MODULE('vfs_default',
                  subsystem='vfs',
                  source='vfs_default.c',
@@ -239,7 +242,7 @@ bld.SAMBA3_MODULE('vfs_tru64acl',
 bld.SAMBA3_MODULE('vfs_catia',
                  subsystem='vfs',
                  source='vfs_catia.c',
-                 deps='samba-util',
+                 deps='samba-util STRING_REPLACE',
                  init_function='',
                  internal_module=bld.SAMBA3_IS_STATIC_MODULE('vfs_catia'),
                  enabled=bld.SAMBA3_IS_ENABLED_MODULE('vfs_catia'))