CBSP Server improvements

Change-Id: Id4e661ab9281c394eaa82430d49f7e3dfeab3f57

src/cbc_data.c

@@ -6,6 +6,7 @@
 #include <osmocom/core/utils.h>
 
 #include "cbc_data.h"
+#include "cbsp_server.h"
 
 /* remove a peer from the message */
 int cbc_message_del_peer(struct cbc_message *cbcmsg, struct cbc_peer *peer)
@@ -49,6 +50,23 @@ struct cbc_peer *cbc_peer_by_name(const char *name)
 	return NULL;
 }
 
+/* look-up of cbc_peer by tuple of (remote host, protocol) */
+struct cbc_peer *cbc_peer_by_addr_proto(const char *remote_host, uint16_t remote_port,
+					enum cbc_peer_protocol proto)
+{
+	struct cbc_peer *peer;
+
+	llist_for_each_entry(peer, &g_cbc->peers, list) {
+		if (!strcasecmp(remote_host, peer->remote_host)) {
+			if (peer->remote_port == -1)
+				return peer;
+			else if (remote_port == peer->remote_port)
+				return peer;
+		}
+	}
+	return NULL;
+}
+
 /* create a new cbc_peer */
 struct cbc_peer *cbc_peer_create(const char *name, enum cbc_peer_protocol proto)
 {

src/cbc_data.h

@@ -19,6 +19,9 @@ struct cbc_peer {
 	struct llist_head list;		/* linked to cbc.peers */
 	const char *name;
 
+	char *remote_host;	/* remote IP address in string format */
+	int remote_port;		/* remote port number or -1 for random */
+
 	enum cbc_peer_protocol proto;
 	union {
 		struct osmo_cbsp_cbc_client *cbsp;
@@ -104,6 +107,7 @@ struct cbc_message {
 
 struct cbc {
 	struct {
+		bool permit_unknown_peers;
 	} config;
 
 	struct llist_head messages;	/* cbc_message.list */
@@ -111,3 +115,13 @@ struct cbc {
 };
 
 extern struct cbc *g_cbc;
+
+
+
+int cbc_message_del_peer(struct cbc_message *cbcmsg, struct cbc_peer *peer);
+int cbc_message_add_peer(struct cbc_message *cbcmsg, struct cbc_peer *peer);
+struct cbc_peer *cbc_peer_by_name(const char *name);
+struct cbc_peer *cbc_peer_by_addr_proto(const char *remote_host, uint16_t remote_port,
+					enum cbc_peer_protocol proto);
+struct cbc_peer *cbc_peer_create(const char *name, enum cbc_peer_protocol proto);
+void cbc_peer_remove(struct cbc_peer *peer);

src/cbsp_server.c

@@ -98,6 +98,7 @@ static int cbsp_cbc_closed_cb(struct osmo_stream_srv *conn)
 	struct osmo_cbsp_cbc_client *client = osmo_stream_srv_get_data(conn);
 	LOGPCC(client, LOGL_INFO, "connection closed\n");
 	llist_del(&client->list);
+	osmo_fsm_inst_term(client->fi, OSMO_FSM_TERM_REQUEST, NULL);
 	talloc_free(client);
 	return 0;
 }
@@ -107,12 +108,19 @@ static int cbsp_cbc_accept_cb(struct osmo_stream_srv_link *link, int fd)
 {
 	struct osmo_cbsp_cbc *cbc = osmo_stream_srv_link_get_data(link);
 	struct osmo_cbsp_cbc_client *client = talloc_zero(cbc, struct osmo_cbsp_cbc_client);
+	char remote_ip[INET6_ADDRSTRLEN], portbuf[6];
+	int remote_port;
 	OSMO_ASSERT(client);
 
+	remote_ip[0] = '\0';
+	portbuf[0] = '\0';
+	osmo_sock_get_ip_and_port(fd, remote_ip, sizeof(remote_ip), portbuf, sizeof(portbuf), false);
+	remote_port = atoi(portbuf);
+
 	client->conn = osmo_stream_srv_create(link, link, fd, cbsp_cbc_read_cb, cbsp_cbc_closed_cb, client);
 	if (!client->conn) {
-		LOGP(DCBSP, LOGL_ERROR, "Unable to create stream server for %s\n",
-		     osmo_sock_get_name2(fd));
+		LOGP(DCBSP, LOGL_ERROR, "Unable to create stream server for %s:%d\n",
+			remote_ip, remote_port);
 		talloc_free(client);
 		return -1;
 	}
@@ -123,6 +131,24 @@ static int cbsp_cbc_accept_cb(struct osmo_stream_srv_link *link, int fd)
 		talloc_free(client);
 		return -1;
 	}
+
+	/* Match client to peer */
+	client->peer = cbc_peer_by_addr_proto(remote_ip, remote_port, CBC_PEER_PROTO_CBSP);
+	if (!client->peer) {
+		if (g_cbc->config.permit_unknown_peers) {
+			LOGPCC(client, LOGL_INFO, "Accepting unknown CBSP peer %s:%d\n",
+				remote_ip, remote_port);
+			client->peer = cbc_peer_create(NULL, CBC_PEER_PROTO_CBSP);
+			OSMO_ASSERT(client->peer);
+		} else {
+			LOGPCC(client, LOGL_NOTICE, "Rejecting unknown CBSP peer %s:%d (not permitted)\n",
+				remote_ip, remote_port);
+			osmo_stream_srv_destroy(client->conn);
+			/* FIXME: further cleanup needed? or does close_cb handle everything? */
+			return -1;
+		}
+	}
+
 	LOGPCC(client, LOGL_INFO, "New CBSP client connection\n");
 	llist_add_tail(&client->list, &cbc->clients);
 	osmo_fsm_inst_dispatch(client->fi, CBSP_SRV_E_CMD_RESET, NULL);
@@ -145,6 +171,12 @@ void cbsp_cbc_client_tx(struct osmo_cbsp_cbc_client *client, struct osmo_cbsp_de
 	osmo_stream_srv_send(client->conn, msg);
 }
 
+void cbsp_cbc_client_close(struct osmo_cbsp_cbc_client *client)
+{
+	osmo_stream_srv_destroy(client->conn);
+	/* FIXME: do we need to unlink/free the client? */
+}
+
 /* initialize the CBC-side CBSP server */
 struct osmo_cbsp_cbc *cbsp_cbc_create(void *ctx, const char *bind_ip, int bind_port,
 				      int (*rx_cb)(struct osmo_cbsp_cbc_client *client,

src/cbsp_server.h

@@ -3,6 +3,8 @@
 #include <osmocom/gsm/cbsp.h>
 #include <osmocom/netif/stream.h>
 
+#include "cbc_data.h"
+
 #define LOGPCC(client, level, fmt, args...) \
 	LOGP(DCBSP, level, "%s: " fmt, cbsp_cbc_client_name(client), ## args)
 
@@ -31,10 +33,13 @@ struct osmo_cbsp_cbc_client {
 	struct msgb *rx_msg;
 
 	struct osmo_fsm_inst *fi;
+
+	struct cbc_peer *peer;
 };
 
 const char *cbsp_cbc_client_name(const struct osmo_cbsp_cbc_client *client);
 void cbsp_cbc_client_tx(struct osmo_cbsp_cbc_client *client, struct osmo_cbsp_decoded *cbsp);
+void cbsp_cbc_client_close(struct osmo_cbsp_cbc_client *client);
 struct osmo_cbsp_cbc *cbsp_cbc_create(void *ctx, const char *bind_ip, int bind_port,
 				      int (*rx_cb)(struct osmo_cbsp_cbc_client *client,
 						   struct osmo_cbsp_decoded *dec));