diff --git a/openbsc/src/libmsc/smpp_smsc.h b/openbsc/src/libmsc/smpp_smsc.h
index b1617e6..4b5bd85 100644
--- a/openbsc/src/libmsc/smpp_smsc.h
+++ b/openbsc/src/libmsc/smpp_smsc.h
@@ -12,15 +12,20 @@
 #include <smpp34_structs.h>
 #include <smpp34_params.h>
 
+#define SMPP_SYS_ID_LEN	16
+#define SMPP_PASSWD_LEN	16
+
 enum esme_read_state {
 	READ_ST_IN_LEN = 0,
 	READ_ST_IN_MSG = 1,
 };
 
+struct osmo_smpp_acl;
+
 struct osmo_esme {
 	struct llist_head list;
 	struct smsc *smsc;
-
+	struct osmo_smpp_acl *acl;
 	int use;
 
 	uint32_t own_seq_nr;
@@ -35,15 +40,28 @@
 	struct msgb *read_msg;
 
 	uint8_t smpp_version;
-	char system_id[16+1];
+	char system_id[SMPP_SYS_ID_LEN+1];
 
 	uint8_t bind_flags;
 };
 
+struct osmo_smpp_acl {
+	struct llist_head list;
+	struct smsc *smsc;
+	char *description;
+	char system_id[SMPP_SYS_ID_LEN+1];
+	char passwd[SMPP_PASSWD_LEN+1];
+	int default_route;
+};
+
 struct smsc {
 	struct osmo_fd listen_ofd;
 	struct llist_head esme_list;
-	char system_id[16+1];
+	struct llist_head acl_list;
+	uint16_t listen_port;
+	char system_id[SMPP_SYS_ID_LEN+1];
+	int accept_all;
+	struct osmo_esme *def_route;
 	void *priv;
 };
 
@@ -53,6 +71,11 @@
 void smpp_esme_get(struct osmo_esme *esme);
 void smpp_esme_put(struct osmo_esme *esme);
 
+struct osmo_smpp_acl *smpp_acl_alloc(struct smsc *smsc, const char *sys_id);
+struct osmo_smpp_acl *smpp_acl_by_system_id(struct smsc *smsc,
+					    const char *sys_id);
+void smpp_acl_delete(struct osmo_smpp_acl *acl);
+
 int smpp_tx_submit_r(struct osmo_esme *esme, uint32_t sequence_nr,
 		     uint32_t command_status, char *msg_id);