sandbox: eth: Add a bridge to a real network for sandbox

Implement a bridge between U-Boot's network stack and Linux's raw packet
API allowing the sandbox to send and receive packets using the host
machine's network interface.

This raw Ethernet API requires elevated privileges.  You can either run
as root, or you can add the capability needed like so:

sudo /sbin/setcap "CAP_NET_RAW+ep" /path/to/u-boot

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

3 files changed, 109 insertions, 0 deletions

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index e46e57b..5bd66ea 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -29,4 +29,14 @@ config ETH_SANDBOX
 
 	  This driver is particularly useful in the test/dm/eth.c tests
 
+config ETH_SANDBOX_RAW
+	depends on DM_ETH && SANDBOX
+	default y
+	bool "Sandbox: Bridge to Linux Raw Sockets"
+	help
+	  This driver is a bridge from the bottom of the network stack
+	  in U-Boot to the RAW AF_PACKET API in Linux. This allows real
+	  network traffic to be tested from within sandbox. See
+	  board/sandbox/README.sandbox for more details.
+
 endif # NETDEVICES
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index b9f5db3..2f22151 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_PCNET) += pcnet.o
 obj-$(CONFIG_RTL8139) += rtl8139.o
 obj-$(CONFIG_RTL8169) += rtl8169.o
 obj-$(CONFIG_ETH_SANDBOX) += sandbox.o
+obj-$(CONFIG_ETH_SANDBOX_RAW) += sandbox-raw.o
 obj-$(CONFIG_SH_ETHER) += sh_eth.o
 obj-$(CONFIG_SMC91111) += smc91111.o
 obj-$(CONFIG_SMC911X) += smc911x.o
diff --git a/drivers/net/sandbox-raw.c b/drivers/net/sandbox-raw.c
new file mode 100644
index 0000000..435b874
--- /dev/null
+++ b/drivers/net/sandbox-raw.c
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2015 National Instruments
+ *
+ * (C) Copyright 2015
+ * Joe Hershberger <joe.hershberger@ni.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0
+ */
+
+#include <asm/eth-raw-os.h>
+#include <common.h>
+#include <dm.h>
+#include <malloc.h>
+#include <net.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+
+static int sb_eth_raw_start(struct udevice *dev)
+{
+	struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
+	struct eth_pdata *pdata = dev_get_platdata(dev);
+	const char *interface;
+
+	debug("eth_sandbox_raw: Start\n");
+
+	interface = fdt_getprop(gd->fdt_blob, dev->of_offset,
+					    "host-raw-interface", NULL);
+	if (interface == NULL)
+		return -EINVAL;
+
+	return sandbox_eth_raw_os_start(interface, pdata->enetaddr, priv);
+}
+
+static int sb_eth_raw_send(struct udevice *dev, void *packet, int length)
+{
+	struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
+
+	debug("eth_sandbox_raw: Send packet %d\n", length);
+
+	return sandbox_eth_raw_os_send(packet, length, priv);
+}
+
+static int sb_eth_raw_recv(struct udevice *dev, uchar **packetp)
+{
+	struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
+	int retval;
+	int length;
+
+	retval = sandbox_eth_raw_os_recv(net_rx_packets[0], &length, priv);
+
+	if (!retval && length) {
+		debug("eth_sandbox_raw: received packet %d\n",
+		      length);
+		*packetp = net_rx_packets[0];
+		return length;
+	}
+	return retval;
+}
+
+static void sb_eth_raw_stop(struct udevice *dev)
+{
+	struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
+
+	debug("eth_sandbox_raw: Stop\n");
+
+	sandbox_eth_raw_os_stop(priv);
+}
+
+static const struct eth_ops sb_eth_raw_ops = {
+	.start			= sb_eth_raw_start,
+	.send			= sb_eth_raw_send,
+	.recv			= sb_eth_raw_recv,
+	.stop			= sb_eth_raw_stop,
+};
+
+static int sb_eth_raw_ofdata_to_platdata(struct udevice *dev)
+{
+	struct eth_pdata *pdata = dev_get_platdata(dev);
+
+	pdata->iobase = dev_get_addr(dev);
+	return 0;
+}
+
+static const struct udevice_id sb_eth_raw_ids[] = {
+	{ .compatible = "sandbox,eth-raw" },
+	{ }
+};
+
+U_BOOT_DRIVER(eth_sandbox_raw) = {
+	.name	= "eth_sandbox_raw",
+	.id	= UCLASS_ETH,
+	.of_match = sb_eth_raw_ids,
+	.ofdata_to_platdata = sb_eth_raw_ofdata_to_platdata,
+	.ops	= &sb_eth_raw_ops,
+	.priv_auto_alloc_size = sizeof(struct eth_sandbox_raw_priv),
+	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
+};