VIRT-PHY: Cleanup dirs, makefile, dependencies and formatting code.

Change-Id: Ibd68a03bcc439c262ba513782936c6b62937eaaa

2 files changed, 294 insertions, 0 deletions

diff --git a/src/host/virt_phy/src/shared/osmo_mcast_sock.c b/src/host/virt_phy/src/shared/osmo_mcast_sock.c
new file mode 100644
index 00000000..acc6bcb1
--- /dev/null
+++ b/src/host/virt_phy/src/shared/osmo_mcast_sock.c
@@ -0,0 +1,191 @@
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <osmocom/core/socket.h>
+#include <osmocom/core/select.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <talloc.h>
+#include <unistd.h>
+#include <virtphy/osmo_mcast_sock.h>
+
+struct mcast_server_sock *mcast_server_sock_setup(void *ctx,
+                                                  char* tx_mcast_group,
+                                                  int tx_mcast_port,
+                                                  int loopback)
+{
+	struct mcast_server_sock *serv_sock = talloc_zero(ctx,
+	                struct mcast_server_sock);
+
+	serv_sock->osmo_fd = talloc_zero(ctx, struct osmo_fd);
+	serv_sock->sock_conf = talloc_zero(ctx, struct sockaddr_in);
+
+	// setup mcast server socket
+	serv_sock->osmo_fd->fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (serv_sock->osmo_fd->fd == -1) {
+		perror("Failed to create Multicast Server Socket");
+		return NULL;
+	}
+
+	serv_sock->sock_conf->sin_family = AF_INET;
+	serv_sock->sock_conf->sin_addr.s_addr = inet_addr(tx_mcast_group);
+	serv_sock->sock_conf->sin_port = htons(tx_mcast_port);
+
+	// determines whether sent mcast packets should be looped back to the local sockets.
+	// loopback must be enabled if the mcast client is on the same machine
+	if (setsockopt(serv_sock->osmo_fd->fd, IPPROTO_IP,
+	IP_MULTICAST_LOOP, &loopback, sizeof(loopback)) < 0) {
+		perror("Failed to disable loopback.\n");
+		return NULL;
+	}
+
+	return serv_sock;
+}
+
+struct mcast_client_sock *mcast_client_sock_setup(
+                void *ctx, char* mcast_group, int mcast_port,
+                int (*fd_rx_cb)(struct osmo_fd *ofd, unsigned int what),
+                void *osmo_fd_data)
+{
+	struct mcast_client_sock *client_sock = talloc_zero(ctx,
+	                struct mcast_client_sock);
+	struct sockaddr_in *rx_sock_conf = talloc_zero(NULL,
+	                struct sockaddr_in);
+	int rc, reuseaddr = 1, loopback = 1;
+
+	client_sock->osmo_fd = talloc_zero(ctx, struct osmo_fd);
+	client_sock->mcast_group = talloc_zero(ctx, struct ip_mreq);
+
+	// Create mcast client socket
+	client_sock->osmo_fd->fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (client_sock->osmo_fd->fd == -1) {
+		perror("Could not create mcast client socket");
+		return NULL;
+	}
+
+	// Enable SO_REUSEADDR to allow multiple instances of this application to receive copies of the multicast datagrams.
+	rc = setsockopt(client_sock->osmo_fd->fd,
+	SOL_SOCKET,
+	SO_REUSEADDR, &reuseaddr, sizeof(reuseaddr));
+	if (rc < 0) {
+		perror("Failed to configure REUSEADDR option");
+		return NULL;
+	}
+
+	// Bind to the proper port number with the IP address specified as INADDR_ANY.
+	rx_sock_conf->sin_family = AF_INET;
+	rx_sock_conf->sin_addr.s_addr = htonl(INADDR_ANY);
+	rx_sock_conf->sin_port = htons(mcast_port);
+	rc = bind(client_sock->osmo_fd->fd, (struct sockaddr *)rx_sock_conf,
+	                sizeof(*rx_sock_conf));
+	talloc_free(rx_sock_conf);
+	if (rc < 0) {
+		perror("Could not bind mcast client socket");
+		return NULL;
+	}
+
+	// Enable loopback of msgs to the host.
+	// Loopback must be enabled for the client, so multiple processes are able to recevie a mcast package.
+	rc = setsockopt(client_sock->osmo_fd->fd,
+	IPPROTO_IP,
+	IP_MULTICAST_LOOP, &loopback, sizeof(loopback));
+	if (rc < 0) {
+		perror("Failed to enable IP_MULTICAST_LOOP");
+		return NULL;
+	}
+
+	// Configure and join the multicast group
+	client_sock->mcast_group->imr_multiaddr.s_addr = inet_addr(mcast_group);
+	client_sock->mcast_group->imr_interface.s_addr = htonl(INADDR_ANY);
+	rc = setsockopt(client_sock->osmo_fd->fd,
+	IPPROTO_IP,
+	IP_ADD_MEMBERSHIP, client_sock->mcast_group,
+	                sizeof(*client_sock->mcast_group));
+	if (rc < 0) {
+		perror("Failed to join to mcast goup");
+		return NULL;
+	}
+
+	// configure and register the osmocom filedescriptor
+	client_sock->osmo_fd->cb = fd_rx_cb;
+	client_sock->osmo_fd->when = BSC_FD_READ;
+	client_sock->osmo_fd->data = osmo_fd_data;
+
+	osmo_fd_register(client_sock->osmo_fd);
+
+	return client_sock;
+}
+
+struct mcast_bidir_sock *mcast_bidir_sock_setup(
+                void *ctx, char* tx_mcast_group, int tx_mcast_port,
+                char* rx_mcast_group, int rx_mcast_port, int loopback,
+                int (*fd_rx_cb)(struct osmo_fd *ofd, unsigned int what),
+                void *osmo_fd_data)
+{
+	struct mcast_bidir_sock *bidir_sock = talloc(ctx,
+	                struct mcast_bidir_sock);
+	bidir_sock->rx_sock = mcast_client_sock_setup(ctx, rx_mcast_group,
+	                rx_mcast_port, fd_rx_cb, osmo_fd_data);
+	bidir_sock->tx_sock = mcast_server_sock_setup(ctx, tx_mcast_group,
+	                tx_mcast_port, loopback);
+	if (!bidir_sock->rx_sock || !bidir_sock->tx_sock) {
+		return NULL;
+	}
+	return bidir_sock;
+
+}
+
+int mcast_client_sock_rx(struct mcast_client_sock *client_sock, void* buf,
+                         int buf_len)
+{
+	return recv(client_sock->osmo_fd->fd, buf, buf_len, 0);
+}
+
+int mcast_server_sock_tx(struct mcast_server_sock *serv_sock, void* data,
+                         int data_len)
+{
+	return sendto(serv_sock->osmo_fd->fd, data, data_len, 0,
+	                (struct sockaddr *)serv_sock->sock_conf,
+	                sizeof(*serv_sock->sock_conf));
+}
+
+int mcast_bidir_sock_tx(struct mcast_bidir_sock *bidir_sock, void* data,
+                        int data_len)
+{
+	return mcast_server_sock_tx(bidir_sock->tx_sock, data, data_len);
+}
+int mcast_bidir_sock_rx(struct mcast_bidir_sock *bidir_sock, void* buf,
+                        int buf_len)
+{
+	return mcast_client_sock_rx(bidir_sock->rx_sock, buf, buf_len);
+}
+
+void mcast_client_sock_close(struct mcast_client_sock *client_sock)
+{
+	setsockopt(client_sock->osmo_fd->fd,
+	IPPROTO_IP,
+	IP_DROP_MEMBERSHIP, client_sock->mcast_group,
+	                sizeof(*client_sock->mcast_group));
+	osmo_fd_unregister(client_sock->osmo_fd);
+	client_sock->osmo_fd->fd = -1;
+	client_sock->osmo_fd->when = 0;
+	close(client_sock->osmo_fd->fd);
+	talloc_free(client_sock->mcast_group);
+	talloc_free(client_sock->osmo_fd);
+	talloc_free(client_sock);
+
+}
+void mcast_server_sock_close(struct mcast_server_sock *serv_sock)
+{
+	close(serv_sock->osmo_fd->fd);
+	talloc_free(serv_sock->sock_conf);
+	talloc_free(serv_sock);
+}
+
+void mcast_bidir_sock_close(struct mcast_bidir_sock *bidir_sock)
+{
+	mcast_client_sock_close(bidir_sock->rx_sock);
+	mcast_server_sock_close(bidir_sock->tx_sock);
+	talloc_free(bidir_sock);
+}
diff --git a/src/host/virt_phy/src/shared/virtual_um.c b/src/host/virt_phy/src/shared/virtual_um.c
new file mode 100644
index 00000000..9415bfbb
--- /dev/null
+++ b/src/host/virt_phy/src/shared/virtual_um.c
@@ -0,0 +1,103 @@
+/* Routines for a Virtual Um interface over GSMTAP/UDP */
+
+/* (C) 2015 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <osmocom/core/select.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/socket.h>
+#include <osmocom/core/gsmtap.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/talloc.h>
+#include <virtphy/osmo_mcast_sock.h>
+#include <virtphy/virtual_um.h>
+#include <unistd.h>
+
+/**
+ * Virtual UM interface file descriptor callback.
+ * Should be called by select.c when the fd is ready for reading.
+ */
+static int virt_um_fd_cb(struct osmo_fd *ofd, unsigned int what)
+{
+	struct virt_um_inst *vui = ofd->data;
+
+	// check if the read flag is set
+	if (what & BSC_FD_READ) {
+		// allocate message buffer of specified size
+		struct msgb *msg = msgb_alloc(VIRT_UM_MSGB_SIZE,
+		                "Virtual UM Rx");
+		int rc;
+
+		// read message from fd in message buffer
+		rc = mcast_bidir_sock_rx(vui->mcast_sock, msgb_data(msg),
+		                msgb_tailroom(msg));
+		// rc is number of bytes actually read
+		if (rc > 0) {
+			msgb_put(msg, rc);
+			msg->l1h = msgb_data(msg);
+			// call the l1 callback function for a received msg
+			vui->recv_cb(vui, msg);
+		} else {
+			// TODO: this kind of error handling might be a bit harsh
+			vui->recv_cb(vui, NULL);
+			// Unregister fd from select loop
+			osmo_fd_unregister(ofd);
+			close(ofd->fd);
+			ofd->fd = -1;
+			ofd->when = 0;
+		}
+	}
+
+	return 0;
+}
+
+struct virt_um_inst *virt_um_init(
+                void *ctx, char *tx_mcast_group, uint16_t tx_mcast_port,
+                char *rx_mcast_group, uint16_t rx_mcast_port,
+                void (*recv_cb)(struct virt_um_inst *vui, struct msgb *msg))
+{
+	struct virt_um_inst *vui = talloc_zero(ctx, struct virt_um_inst);
+	vui->mcast_sock = mcast_bidir_sock_setup(ctx, tx_mcast_group,
+	                tx_mcast_port, rx_mcast_group, rx_mcast_port, 1,
+	                virt_um_fd_cb, vui);
+	vui->recv_cb = recv_cb;
+
+	return vui;
+
+}
+
+void virt_um_destroy(struct virt_um_inst *vui)
+{
+	mcast_bidir_sock_close(vui->mcast_sock);
+	talloc_free(vui);
+}
+
+/**
+ * Write msg to to multicast socket and free msg afterwards
+ */
+int virt_um_write_msg(struct virt_um_inst *vui, struct msgb *msg)
+{
+	int rc;
+
+	rc = mcast_bidir_sock_tx(vui->mcast_sock, msgb_data(msg),
+	                msgb_length(msg));
+	msgb_free(msg);
+
+	return rc;
+}