initial skeleton for accepting UMA/GAN connections

1 files changed, 145 insertions, 0 deletions

diff --git a/openbsc/src/osmo-ganc/conn.c b/openbsc/src/osmo-ganc/conn.c
new file mode 100644
index 000000000..1c252757f
--- /dev/null
+++ b/openbsc/src/osmo-ganc/conn.c
@@ -0,0 +1,145 @@
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/fcntl.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/select.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/socket.h>
+#include <osmocom/core/write_queue.h>
+
+#include "conn.h"
+
+
+static int slave_read_cb(struct osmo_fd *ofd)
+{
+	struct osmo_conn *conn = ofd->data;
+
+	return conn->link->slave_read_cb(conn);
+}
+
+static int slave_write_cb(struct osmo_fd *ofd, struct msgb *msg)
+{
+	int rc;
+
+	rc = send(ofd->fd, msg->data, msg->len, 0);
+	if (rc < 0) {
+		LOGP(DLINP, LOGL_ERROR, "error %d on send()\n", rc);
+	}
+
+	return rc;
+}
+
+static int server_fd_cb(struct osmo_fd *ofd, unsigned int what)
+{
+	int rc;
+	struct sockaddr_in sa;
+	socklen_t sa_len = sizeof(sa);
+	struct osmo_link *link = ofd->data;
+	struct osmo_conn *conn;
+
+	rc = accept(ofd->fd, (struct sockaddr *)&sa, &sa_len);
+	if (rc < 0)
+		return rc;
+
+	conn = talloc_zero(link, struct osmo_conn);
+	if (!conn) {
+		close(rc);
+		return -ENOMEM;
+	}
+
+	conn->link = link;
+	osmo_wqueue_init(&conn->queue, link->slave_max_qlen);
+	conn->queue.read_cb = slave_read_cb;
+	conn->queue.write_cb = slave_write_cb;
+
+	conn->queue.bfd.when = BSC_FD_READ | BSC_FD_WRITE;
+	conn->queue.bfd.data = conn;
+
+	conn->remote.host = talloc_strdup(conn, inet_ntoa(sa.sin_addr));
+	conn->remote.port = ntohs(sa.sin_port);
+
+	llist_add_tail(&conn->list, &link->conns);
+
+	LOGP(DLINP, LOGL_NOTICE, "accept()ed new UNC link from %s:%u to port %u\n",
+		conn->remote.host, conn->remote.port, link->port);
+
+	if (link->accept_cb)
+		link->accept_cb(conn);
+
+	return 0;
+}
+
+struct osmo_link *osmo_link_create(void *ctx, const char *addr, uint16_t port,
+				   int (*read_cb)(struct osmo_conn *),
+				   int slave_max_qlen)
+{
+	struct osmo_link *link;
+
+	link = talloc_zero(ctx, struct osmo_link);
+	if (!link)
+		return NULL;
+
+	link->ofd.when = BSC_FD_READ | BSC_FD_WRITE;
+	link->ofd.cb = server_fd_cb;
+	link->ofd.data = link;
+	link->addr = talloc_strdup(link, addr);
+	link->port = port;
+	link->slave_read_cb = read_cb;
+	link->slave_max_qlen = slave_max_qlen;
+	INIT_LLIST_HEAD(&link->conns);
+
+	return link;
+}
+
+
+int osmo_link_listen(struct osmo_link *link,
+		     void (*accept_cb)(struct osmo_conn *))
+{
+	int rc;
+
+	rc = osmo_sock_init(AF_INET, SOCK_STREAM, IPPROTO_TCP,
+			    link->addr, link->port, OSMO_SOCK_F_BIND);
+
+	link->ofd.fd = rc;
+
+	if (osmo_fd_register(&link->ofd) < 0) {
+		close(rc);
+		return -EIO;
+	}
+	link->accept_cb = accept_cb;
+
+	return 0;
+}
+
+int osmo_conn_enqueue(struct osmo_conn *conn, struct msgb *msg)
+{
+	return osmo_wqueue_enqueue(&conn->queue, msg);
+}
+
+void osmo_conn_close(struct osmo_conn *conn)
+{
+	close(conn->queue.bfd.fd);
+	osmo_wqueue_clear(&conn->queue);
+	llist_del(&conn->list);
+
+	talloc_free(conn);
+}
+
+int osmo_link_close(struct osmo_link *link)
+{
+	struct osmo_conn *conn, *conn2;
+
+	osmo_fd_unregister(&link->ofd);
+	close(link->ofd.fd);
+
+	llist_for_each_entry_safe(conn, conn2, &link->conns, list)
+		osmo_conn_close(conn);
+
+	return 0;
+}