[PATCH v5 14/14] add ethlog command

[Oleksij Rempel]

It is kind of tcpdump or tshark for barebox. Instead of starting
application it will let barebox dump everything to the console by still
allowing to use other application.

Signed-off-by: Oleksij Rempel <o.rempel at pengutronix.de>
---
 commands/Kconfig  |  8 +++++
 commands/Makefile |  1 +
 commands/ethlog.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++
 include/net.h     | 11 +++++++
 net/eth.c         |  4 +--
 net/net.c         |  3 ++
 6 files changed, 105 insertions(+), 2 deletions(-)
 create mode 100644 commands/ethlog.c

diff --git a/commands/Kconfig b/commands/Kconfig
index caef1e8fb5..c5505321cf 100644
--- a/commands/Kconfig
+++ b/commands/Kconfig
@@ -1272,6 +1272,14 @@ config CMD_IP_ROUTE_GET
 	  be shown on the command line or alternatively a variable is set to
 	  the result.
 
+config CMD_ETHLOG
+	tristate
+	prompt "ethlog"
+	help
+	  log ethernet traffic.
+
+	  Usage: ethlog [-r] [DEVICENAME]
+
 # end Network commands
 endmenu
 
diff --git a/commands/Makefile b/commands/Makefile
index fffb6d979e..b3b7bafe6b 100644
--- a/commands/Makefile
+++ b/commands/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_CMD_MEMCMP)	+= memcmp.o
 obj-$(CONFIG_CMD_MEMCPY)	+= memcpy.o
 obj-$(CONFIG_CMD_MEMSET)	+= memset.o
 obj-$(CONFIG_CMD_EDIT)		+= edit.o
+obj-$(CONFIG_CMD_ETHLOG)	+= ethlog.o
 obj-$(CONFIG_CMD_EXEC)		+= exec.o
 obj-$(CONFIG_CMD_SLEEP)		+= sleep.o
 obj-$(CONFIG_CMD_SMC)		+= smc.o
diff --git a/commands/ethlog.c b/commands/ethlog.c
new file mode 100644
index 0000000000..0cc93ba808
--- /dev/null
+++ b/commands/ethlog.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// SPDX-FileCopyrightText: (c) 2022 Pengutronix,
+//                             Oleksij Rempel <o.rempel at pengutronix.de>
+
+#include <common.h>
+#include <command.h>
+#include <complete.h>
+#include <environment.h>
+#include <getopt.h>
+#include <net.h>
+
+static void ethlog_rx_monitor(struct eth_device *edev, void *packet,
+			       int length)
+{
+	dev_print_hex_dump(&edev->dev, KERN_DEBUG, "rx data <: ",
+			   DUMP_PREFIX_OFFSET, 16, 1, packet, length, true);
+	printk("\n");
+}
+
+static void ethlog_tx_monitor(struct eth_device *edev, void *packet,
+			       int length)
+{
+	dev_print_hex_dump(&edev->dev, KERN_DEBUG, "tx data >: ",
+			   DUMP_PREFIX_OFFSET, 16, 1, packet, length, true);
+	printk("\n");
+}
+
+static int do_ethlog(int argc, char *argv[])
+{
+	struct eth_device *edev;
+	const char *edevname;
+	bool remove = false;
+	int opt;
+
+	while ((opt = getopt(argc, argv, "r")) > 0) {
+		switch (opt) {
+		case 'r':
+			remove = true;
+			break;
+		default:
+			return COMMAND_ERROR_USAGE;
+		}
+	}
+
+	if (optind == argc)
+		edevname = "eth0";
+	else
+		edevname = argv[optind];
+
+	edev = eth_get_byname(edevname);
+	if (!edev) {
+		printf("No such network device: %s\n", edevname);
+		return 1;
+	}
+
+	if (remove) {
+		edev->tx_monitor = NULL;
+		edev->rx_monitor = NULL;
+
+		return 0;
+	}
+
+	edev->tx_monitor = ethlog_tx_monitor;
+	edev->rx_monitor = ethlog_rx_monitor;
+
+	return 0;
+}
+
+BAREBOX_CMD_HELP_START(ethlog)
+BAREBOX_CMD_HELP_TEXT("Options:")
+BAREBOX_CMD_HELP_OPT("-r", "remove log handler from Ethernet interface")
+BAREBOX_CMD_HELP_END
+
+BAREBOX_CMD_START(ethlog)
+	.cmd		= do_ethlog,
+	BAREBOX_CMD_DESC("ETHLOG - tool to get dump of Ethernet packets")
+	BAREBOX_CMD_OPTS("[-r] [device]")
+	BAREBOX_CMD_GROUP(CMD_GRP_NET)
+	BAREBOX_CMD_COMPLETE(eth_complete)
+BAREBOX_CMD_END
diff --git a/include/net.h b/include/net.h
index 8013f79c2e..b50b6e76c8 100644
--- a/include/net.h
+++ b/include/net.h
@@ -46,6 +46,8 @@ struct eth_device {
 	int  (*set_ethaddr) (struct eth_device*, const unsigned char *adr);
 	int  (*rx_preprocessor) (struct eth_device*, unsigned char **packet,
 				 int *length);
+	void (*rx_monitor) (struct eth_device*, void *packet, int length);
+	void (*tx_monitor) (struct eth_device*, void *packet, int length);
 
 	struct eth_device *next;
 	void *priv;
@@ -90,6 +92,15 @@ static inline const char *eth_name(struct eth_device *edev)
 	return edev->devname;
 }
 
+static inline int eth_send_raw(struct eth_device *edev, void *packet,
+			       int length)
+{
+	if (edev->tx_monitor)
+		edev->tx_monitor(edev, packet, length);
+
+	return edev->send(edev, packet, length);
+}
+
 int eth_register(struct eth_device* dev);    /* Register network device		*/
 void eth_unregister(struct eth_device* dev); /* Unregister network device	*/
 int eth_set_ethaddr(struct eth_device *edev, const char *ethaddr);
diff --git a/net/eth.c b/net/eth.c
index e9e53341f3..bc641dc8e4 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -245,7 +245,7 @@ int eth_send(struct eth_device *edev, void *packet, int length)
 
 	led_trigger_network(LED_TRIGGER_NET_TX);
 
-	ret = edev->send(edev, packet, length);
+	ret = eth_send_raw(edev, packet, length);
 
 	slice_release(eth_device_slice(edev));
 
@@ -272,7 +272,7 @@ static void eth_do_work(struct eth_device *edev)
 
 	list_for_each_entry_safe(q, tmp, &edev->send_queue, list) {
 		led_trigger_network(LED_TRIGGER_NET_TX);
-		edev->send(edev, q->data, q->length);
+		eth_send_raw(edev, q->data, q->length);
 		list_del(&q->list);
 		free(q->data);
 		free(q);
diff --git a/net/net.c b/net/net.c
index 0b8e4caa0e..eae45e1843 100644
--- a/net/net.c
+++ b/net/net.c
@@ -708,6 +708,9 @@ int net_receive(struct eth_device *edev, unsigned char *pkt, int len)
 		goto out;
 	}
 
+	if (edev->rx_monitor)
+		edev->rx_monitor(edev, pkt, len);
+
 	if (edev->rx_preprocessor) {
 		ret = edev->rx_preprocessor(edev, &pkt, &len);
 		if (ret == -ENOMSG)
-- 
2.30.2