[sccp] Implement parts of ITU SCCP for use in the A-Interface
include/sccp/sccp_types.h contain Q.713 and GSM definitions
include/sccp/sccp.h is the application interface resembling
the esentials of the UNIX socket interface.
src/sccp.c is the actual implementation of SCCP featuring
connection and UDT1 support.
tests/sccp/sccp.c is testing connection creation and formating
of the SCCP messages used by the A-interface. And
it contains a simple fuzzing test to test the
robustnes of the implementation.
diff --git a/openbsc/include/sccp/sccp.h b/openbsc/include/sccp/sccp.h
new file mode 100644
index 0000000..8ee4b68
--- /dev/null
+++ b/openbsc/include/sccp/sccp.h
@@ -0,0 +1,145 @@
+/*
+ * SCCP management code
+ *
+ * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
+ *
+ * All Rights Reserved
+ *
+ * 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 2 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, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#ifndef SCCP_H
+#define SCCP_H
+
+#include <stdlib.h>
+
+#include <sys/socket.h>
+
+#include <openbsc/msgb.h>
+
+#include "sccp_types.h"
+
+struct sccp_system;
+
+enum {
+ SCCP_CONNECTION_STATE_NONE,
+ SCCP_CONNECTION_STATE_REQUEST,
+ SCCP_CONNECTION_STATE_CONFIRM,
+ SCCP_CONNECTION_STATE_ESTABLISHED,
+ SCCP_CONNECTION_STATE_RELEASE,
+ SCCP_CONNECTION_STATE_RELEASE_COMPLETE,
+ SCCP_CONNECTION_STATE_REFUSED,
+ SCCP_CONNECTION_STATE_SETUP_ERROR,
+};
+
+struct sockaddr_sccp {
+ sa_family_t sccp_family; /* AF_SCCP in the future??? */
+ u_int8_t sccp_ssn; /* subssystem number for routing */
+
+ /* TODO fill in address indicator... if that is ever needed */
+
+ /* not sure about these */
+ /* u_int8_t sccp_class; */
+};
+
+/*
+ * parsed structure of an address
+ */
+struct sccp_address {
+ struct sccp_called_party_address address;
+ u_int8_t ssn;
+ u_int8_t poi[2];
+};
+
+struct sccp_optional_data {
+ u_int8_t data_len;
+ u_int8_t data_start;
+};
+
+struct sccp_connection {
+ /* public */
+ void *data_ctx;
+ void (*data_cb)(struct sccp_connection *conn, struct msgb *msg, unsigned int len);
+
+ void *state_ctx;
+ void (*state_cb)(struct sccp_connection *, int old_state);
+
+ struct sccp_source_reference source_local_reference;
+ struct sccp_source_reference destination_local_reference;
+
+ int connection_state;
+
+ /* private */
+ /* list of active connections */
+ struct llist_head list;
+ struct sccp_system *system;
+ int incoming;
+};
+
+/**
+ * system functionality to implement on top of any other transport layer:
+ * call sccp_system_incoming for incoming data (from the network)
+ * sccp will call outgoing whenever outgoing data exists
+ */
+int sccp_system_init(int (*outgoing)(struct msgb *data, void *ctx), void *context);
+int sccp_system_incoming(struct msgb *data);
+
+/**
+ * Send data on an existing connection
+ */
+int sccp_connection_write(struct sccp_connection *connection, struct msgb *data);
+int sccp_connection_close(struct sccp_connection *connection, int cause);
+int sccp_connection_free(struct sccp_connection *connection);
+
+/**
+ * Create a new socket. Set your callbacks and then call bind to open
+ * the connection.
+ */
+struct sccp_connection *sccp_connection_socket(void);
+
+/**
+ * Open the connection and send additional data
+ */
+int sccp_connection_connect(struct sccp_connection *conn,
+ const struct sockaddr_sccp *sccp_called,
+ struct msgb *data);
+
+/**
+ * mostly for testing purposes only. Set the accept callback.
+ * TODO: add true routing information... in analogy to socket, bind, accept
+ */
+int sccp_connection_set_incoming(const struct sockaddr_sccp *sock,
+ int (*accept_cb)(struct sccp_connection *connection, void *data),
+ void *user_data);
+
+/**
+ * Send data in terms of unit data. A fixed address indicator will be used.
+ */
+int sccp_write(struct msgb *data,
+ const struct sockaddr_sccp *sock_sender,
+ const struct sockaddr_sccp *sock_target, int class);
+int sccp_set_read(const struct sockaddr_sccp *sock,
+ int (*read_cb)(struct msgb *msgb, unsigned int, void *user_data),
+ void *user_data);
+
+/* generic sock addresses */
+extern const struct sockaddr_sccp sccp_ssn_bssap;
+
+/* helpers */
+u_int32_t sccp_src_ref_to_int(struct sccp_source_reference *ref);
+struct sccp_source_reference sccp_src_ref_from_int(u_int32_t);
+
+#endif