[PATCH v6 10/12] net/netcat: add netcat over tcp support

10 Sep 2024

This patch adds downloading/uploading of data with netcat.
Client/server mode both supported.
How to test:
============
  netcat-openbsd=1.219-1 from debian were used for a tests
a) Load data from remote host.
       * U-Boot listen on tcp port 3456
       * PC connects
u-boot: netcat load ${loadaddr} 3456
     PC:     netcat -q1 ${UBOOT_IP} 3456 < image.itb
b) Load data from remote host.
       * PC listen on tcp port 3456
       * U-Boot connects
PC:     netcat -q1 -l -p 3456 < image.itb
     u-boot: netcat load ${loadaddr} ${PC_IP}:3456
c) Save data to remote host
       * U-Boot listen on tcp port 3456
       * PC connects
u-boot: netcat save ${loadaddr} ${data_size_in_hex} 3456
     PC:     netcat -w1 ${UBOOT_IP} 3456 >image.itb
d) Save data to remote host
       * PC listen on tcp port 3456
       * U-Boot connects
PC:     netcat -w1 -l -p 3456 >image.itb
     u-boot: netcat save ${loadaddr} ${data_size_in_hex} ${PC_IP}:3456
Signed-off-by: Mikhail Kshevetskiy mikhail.kshevetskiy@iopsys.eu
---
 cmd/Kconfig          |   7 ++
 cmd/net.c            |  34 ++++++--
 include/net.h        |   2 +-
 include/net/netcat.h |  20 +++++
 net/Makefile         |   1 +
 net/net.c            |   9 +++
 net/netcat.c         | 181 +++++++++++++++++++++++++++++++++++++++++++
 7 files changed, 248 insertions(+), 6 deletions(-)
 create mode 100644 include/net/netcat.h
 create mode 100644 net/netcat.c

diff --git a/cmd/Kconfig b/cmd/Kconfig
index 978f44eda42..abcd003f7f1 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -2007,6 +2007,13 @@ config CMD_WGET
      wget is a simple command to download kernel, or other files,
      from a http server over TCP.
+config CMD_NETCAT
+	bool "netcat"
+	select PROT_TCP
+	help
+	  netcat is a simple command to load/store kernel, or other files,
+	  using netcat like manner over TCP.
+
 config CMD_MII
    bool "mii"
    imply CMD_MDIO
diff --git a/cmd/net.c b/cmd/net.c
index 53ce2bc5d0c..364139ec5b9 100644
--- a/cmd/net.c
+++ b/cmd/net.c
@@ -206,6 +206,28 @@ U_BOOT_CMD(
 );
 #endif
+#if defined(CONFIG_CMD_NETCAT)
+static int do_netcat(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
+{
+	if (argc < 2)
+		return 1;
+
+	if (!strcmp(argv[1], "load"))
+		return netboot_common(NETCAT_LOAD, cmdtp, argc - 1, argv + 1);
+	else if (!strcmp(argv[1], "save"))
+		return netboot_common(NETCAT_SAVE, cmdtp, argc - 1, argv + 1);
+	else
+		return 1;
+}
+
+U_BOOT_CMD(
+	netcat,   5,      1,      do_netcat,
+	"load/store data via tcp netcat utility",
+	"load [loadAddress] [[hostIPaddr:]port]\n"
+	"save Address Size [[hostIPaddr:]port]\n"
+);
+#endif
+
 static void netboot_update_env(void)
 {
    char tmp[46];
@@ -323,16 +345,17 @@ static int parse_args(enum proto_t proto, int argc, char *const argv[])
switch (argc) {
    case 1:
-		if (IS_ENABLED(CONFIG_CMD_TFTPPUT) && proto == TFTPPUT)
+		if ((IS_ENABLED(CONFIG_CMD_TFTPPUT) && proto == TFTPPUT) ||
+		    (IS_ENABLED(CONFIG_CMD_NETCAT) && proto == NETCAT_SAVE))
    		return 1;
-
    	/* refresh bootfile name from env */
    	copy_filename(net_boot_file_name, env_get("bootfile"),
    		      sizeof(net_boot_file_name));
    	break;
case 2:
-		if (IS_ENABLED(CONFIG_CMD_TFTPPUT) && proto == TFTPPUT)
+		if ((IS_ENABLED(CONFIG_CMD_TFTPPUT) && proto == TFTPPUT) ||
+		    (IS_ENABLED(CONFIG_CMD_NETCAT) && proto == NETCAT_SAVE))
    		return 1;
    	/*
    	 * Only one arg - accept two forms:
@@ -354,7 +377,8 @@ static int parse_args(enum proto_t proto, int argc, char *const argv[])
    	break;
case 3:
-		if (IS_ENABLED(CONFIG_CMD_TFTPPUT) && proto == TFTPPUT) {
+		if ((IS_ENABLED(CONFIG_CMD_TFTPPUT) && proto == TFTPPUT) ||
+		    (IS_ENABLED(CONFIG_CMD_NETCAT) && proto == NETCAT_SAVE)) {
    		if (parse_addr_size(argv))
    			return 1;
    	} else {
@@ -365,7 +389,7 @@ static int parse_args(enum proto_t proto, int argc, char *const argv[])
    	}
    	break;
-#ifdef CONFIG_CMD_TFTPPUT
+#if defined(CONFIG_CMD_TFTPPUT) || defined(CONFIG_CMD_NETCAT)
    case 4:
    	if (parse_addr_size(argv))
    		return 1;
diff --git a/include/net.h b/include/net.h
index b0ce13e0a9d..0af6493788a 100644
--- a/include/net.h
+++ b/include/net.h
@@ -515,7 +515,7 @@ extern int		net_restart_wrap;	/* Tried all network devices */
 enum proto_t {
    BOOTP, RARP, ARP, TFTPGET, DHCP, DHCP6, PING, PING6, DNS, NFS, CDP,
    NETCONS, SNTP, TFTPSRV, TFTPPUT, LINKLOCAL, FASTBOOT_UDP, FASTBOOT_TCP,
-	WOL, UDP, NCSI, WGET, RS
+	WOL, UDP, NCSI, WGET, NETCAT_LOAD, NETCAT_SAVE, RS
 };
extern char	net_boot_file_name[1024];/* Boot File name */
diff --git a/include/net/netcat.h b/include/net/netcat.h
new file mode 100644
index 00000000000..d8e09aaaa55
--- /dev/null
+++ b/include/net/netcat.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: BSD-2-Clause
+ *
+ * netcat include file
+ * Copyright (C) 2024 IOPSYS Software Solutions AB
+ * Author: Mikhail Kshevetskiy mikhail.kshevetskiy@iopsys.eu
+ */
+#ifndef __NET_NETCAT_TCP_H__
+#define __NET_NETCAT_TCP_H__
+
+/**
+ * netcat_load_start() - begin netcat in loading mode
+ */
+void netcat_load_start(void);
+
+/**
+ * netcat_save_start() - begin netcat in data saving mode
+ */
+void netcat_save_start(void);
+
+#endif /* __NET_NETCAT_TCP_H__ */
diff --git a/net/Makefile b/net/Makefile
index 64ab7ec740a..dac7b4859fb 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_CMD_WOL)  += wol.o
 obj-$(CONFIG_PROT_UDP) += udp.o
 obj-$(CONFIG_PROT_TCP) += tcp.o
 obj-$(CONFIG_CMD_WGET) += wget.o
+obj-$(CONFIG_CMD_NETCAT) += netcat.o
# Disable this warning as it is triggered by:
 # sprintf(buf, index ? "foo%d" : "foo", index)
diff --git a/net/net.c b/net/net.c
index 86182cc504e..d81604a57ce 100644
--- a/net/net.c
+++ b/net/net.c
@@ -108,6 +108,7 @@
 #include <test/test.h>
 #include <net/tcp.h>
 #include <net/wget.h>
+#include <net/netcat.h>
 #include "arp.h"
 #include "bootp.h"
 #include "cdp.h"
@@ -564,6 +565,14 @@ restart:
    		wget_start();
    		break;
 #endif
+#if defined(CONFIG_CMD_NETCAT)
+		case NETCAT_LOAD:
+			netcat_load_start();
+			break;
+		case NETCAT_SAVE:
+			netcat_save_start();
+			break;
+#endif
 #if defined(CONFIG_CMD_CDP)
    	case CDP:
    		cdp_start();
diff --git a/net/netcat.c b/net/netcat.c
new file mode 100644
index 00000000000..633afe5c60b
--- /dev/null
+++ b/net/netcat.c
@@ -0,0 +1,181 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * netcat support driver
+ * Copyright (C) 2024 IOPSYS Software Solutions AB
+ * Author: Mikhail Kshevetskiy mikhail.kshevetskiy@iopsys.eu
+ */
+
+#include <command.h>
+#include <display_options.h>
+#include <env.h>
+#include <image.h>
+#include <mapmem.h>
+#include <net.h>
+#include <net/tcp.h>
+#include <net/netcat.h>
+
+#define HASHES_PER_LINE		65
+
+static struct in_addr		server_ip;
+static u16			server_port;
+static u16			local_port;
+static int			listen;
+static int			reading;
+static unsigned int		packets;
+static enum net_loop_state	netcat_loop_state;
+
+static void show_block_marker(void)
+{
+	if ((packets % 10) == 0)
+		putc('#');
+	else if (((packets + 1) % (10 * HASHES_PER_LINE)) == 0)
+		puts("\n");
+}
+
+static void tcp_stream_on_closed(struct tcp_stream *tcp)
+{
+	if (tcp->status != TCP_ERR_OK)
+		netcat_loop_state = NETLOOP_FAIL;
+
+	/*
+	 * The status line will be shown after the download/upload
+	 * progress (see show_block_marker() function). This progress
+	 * generally have no final "\n", so jump to new line before
+	 * output the status
+	 */
+	if (netcat_loop_state != NETLOOP_SUCCESS)
+		printf("\nnetcat: Transfer Fail, TCP status - %d\n", tcp->status);
+	else
+		printf("\nPackets %s %d, Transfer Successful\n",
+		       reading ? "received" : "transmitted", packets);
+	net_set_state(netcat_loop_state);
+}
+
+static void tcp_stream_on_rcv_nxt_update(struct tcp_stream *tcp, u32 rx_bytes)
+{
+	net_boot_file_size = rx_bytes;
+	show_block_marker();
+}
+
+static void tcp_stream_on_snd_una_update(struct tcp_stream *tcp, u32 tx_bytes)
+{
+	show_block_marker();
+	if (tx_bytes == image_save_size)
+		tcp_stream_close(tcp);
+}
+
+static void tcp_stream_on_established(struct tcp_stream *tcp)
+{
+	netcat_loop_state = NETLOOP_SUCCESS;
+}
+
+static u32 tcp_stream_rx(struct tcp_stream *tcp, u32 rx_offs, void *buf, u32 len)
+{
+	void *ptr;
+
+	packets++;
+	ptr = map_sysmem(image_load_addr + rx_offs, len);
+	memcpy(ptr, buf, len);
+	unmap_sysmem(ptr);
+	return len;
+}
+
+static u32 tcp_stream_tx(struct tcp_stream *tcp, u32 tx_offs, void *buf, u32 maxlen)
+{
+	void *ptr;
+
+	if (tx_offs + maxlen > image_save_size)
+		maxlen = image_save_size - tx_offs;
+	if (maxlen == 0)
+		return 0;
+
+	packets++;
+	ptr = map_sysmem(image_save_addr + tx_offs, maxlen);
+	memcpy(buf, ptr, maxlen);
+	unmap_sysmem(ptr);
+	return maxlen;
+}
+
+/*
+ * This function will be called on new connections (incoming or outgoing)
+ * It MUST:
+ *   -- setup required tcp_stream callbacks (if connection will be accepted)
+ *   -- return a connection verdict:
+ *        0: discard connection
+ *        1: accept connection
+ */
+static int tcp_stream_on_create(struct tcp_stream *tcp)
+{
+	if (listen) {
+		/*
+		 * We are listening for incoming connections.
+		 * Accept connections to netcat listen port only.
+		 */
+		if (tcp->lport != local_port)
+			return 0;
+	} else {
+		/*
+		 * We are connecting to remote host.
+		 * Check remote IP:port to make sure that this is our connection
+		 */
+		if ((tcp->rhost.s_addr != server_ip.s_addr) ||
+		    (tcp->rport != server_port))
+			return 0;
+	}
+
+	netcat_loop_state = NETLOOP_FAIL;
+	net_boot_file_size = 0;
+	packets = 0;
+
+	tcp->on_closed = tcp_stream_on_closed;
+	tcp->on_established = tcp_stream_on_established;
+	if (reading) {
+		tcp->on_rcv_nxt_update = tcp_stream_on_rcv_nxt_update;
+		tcp->rx = tcp_stream_rx;
+	} else {
+		tcp->on_snd_una_update = tcp_stream_on_snd_una_update;
+		tcp->tx = tcp_stream_tx;
+	}
+	return 1;
+}
+
+static void netcat_start(void)
+{
+	struct tcp_stream *tcp;
+
+	memset(net_server_ethaddr, 0, 6);
+	tcp_stream_set_on_create_handler(tcp_stream_on_create);
+
+	if (strchr(net_boot_file_name, ':') == NULL) {
+		listen = 1;
+		printf("Listening on port %s...\n", net_boot_file_name);
+
+		local_port = dectoul(net_boot_file_name, NULL);
+	} else {
+		listen = 0;
+		printf("Connecting to %s...\n", net_boot_file_name);
+
+		server_ip = string_to_ip(net_boot_file_name);
+		server_port = dectoul(strchr(net_boot_file_name, ':') + 1, NULL);
+
+		tcp = tcp_stream_connect(server_ip, server_port);
+		if (tcp == NULL) {
+			printf("No free tcp streams\n");
+			net_set_state(NETLOOP_FAIL);
+			return;
+		}
+		tcp_stream_put(tcp);
+	}
+}
+
+void netcat_load_start(void)
+{
+	reading = 1;
+	return netcat_start();
+}
+
+void netcat_save_start(void)
+{
+	reading = 0;
+	return netcat_start();
+}
-- 
2.45.2


    