[U-Boot] [PATCH v2 1/1] net: new command: wol - Wake on LAN
Lothar Felten
lothar.felten at gmail.com
Fri Jun 22 20:29:54 UTC 2018
Add a new command 'wol': Wait for an incoming Wake-on-LAN packet or
time out if no WoL packed is received.
If the WoL packet contains a password, it is saved in the environment
variable 'wolpassword' using the etherwake format (dot or colon
separated decimals).
Intended use case: a networked device should boot an alternate image.
It's attached to a network on a client site, modifying the DHCP server
configuration or setup of a tftp server is not allowed.
After power on the device waits a few seconds for a WoL packet. If a
packet is received, the device boots the alternate image. Otherwise
it boots the default image.
This method is a simple way to interact with a system via network even
if only the MAC address is known. Tools to send WoL packets are
available on all common platforms.
Some ethernet drivers seem to pad the incoming packet. The additional
padding bytes might be recognized as Wake-on-LAN password bytes.
By default enabled in pengwyn_defconfig.
Signed-off-by: Lothar Felten <lothar.felten at gmail.com>
---
Changes v1 -> v2:
- UDP support (suggested by Joe Hershberger)
- moved to separate command file cmd/wol.c
- style and formatting
cmd/Kconfig | 5 +++
cmd/Makefile | 1 +
cmd/wol.c | 33 ++++++++++++++++
configs/pengwyn_defconfig | 1 +
include/net.h | 3 +-
net/Makefile | 1 +
net/net.c | 19 ++++++++++
net/wol.c | 96 +++++++++++++++++++++++++++++++++++++++++++++++
net/wol.h | 65 ++++++++++++++++++++++++++++++++
9 files changed, 223 insertions(+), 1 deletion(-)
create mode 100644 cmd/wol.c
create mode 100644 net/wol.c
create mode 100644 net/wol.h
diff --git a/cmd/Kconfig b/cmd/Kconfig
index 1eb55e5250..00c208843d 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1239,6 +1239,11 @@ config CMD_PXE
help
Boot image via network using PXE protocol
+config CMD_WOL
+ bool "wol"
+ help
+ Wait for wake-on-lan Magic Packet
+
endif
menu "Misc commands"
diff --git a/cmd/Makefile b/cmd/Makefile
index e0088df33b..2875fd4b4b 100644
--- a/cmd/Makefile
+++ b/cmd/Makefile
@@ -100,6 +100,7 @@ obj-$(CONFIG_CMD_PCI) += pci.o
endif
obj-y += pcmcia.o
obj-$(CONFIG_CMD_PXE) += pxe.o
+obj-$(CONFIG_CMD_WOL) += wol.o
obj-$(CONFIG_CMD_QFW) += qfw.o
obj-$(CONFIG_CMD_READ) += read.o
obj-$(CONFIG_CMD_REGINFO) += reginfo.o
diff --git a/cmd/wol.c b/cmd/wol.c
new file mode 100644
index 0000000000..91b3929025
--- /dev/null
+++ b/cmd/wol.c
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2018
+ * Lothar Felte, lothar.felten at gmail.com
+ */
+
+/*
+ * Wake-on-LAN support
+ */
+#include <common.h>
+#include <command.h>
+#include <net.h>
+
+#if defined(CONFIG_CMD_WOL)
+void wol_set_timeout(ulong);
+
+int do_wol(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+ /* Validate arguments */
+ if (argc < 2)
+ return CMD_RET_USAGE;
+ wol_set_timeout(simple_strtol(argv[1], NULL, 10) * 1000);
+ if (net_loop(WOL) < 0)
+ return CMD_RET_FAILURE;
+ return CMD_RET_SUCCESS;
+}
+
+U_BOOT_CMD(
+ wol, 2, 1, do_wol,
+ "wait for an incoming wake-on-lan packet",
+ "Timeout"
+);
+#endif
diff --git a/configs/pengwyn_defconfig b/configs/pengwyn_defconfig
index 0ee8e6e1b9..76b5715a99 100644
--- a/configs/pengwyn_defconfig
+++ b/configs/pengwyn_defconfig
@@ -37,6 +37,7 @@ CONFIG_CMD_MMC=y
CONFIG_CMD_NAND=y
CONFIG_CMD_SPI=y
CONFIG_CMD_USB=y
+CONFIG_CMD_WOL=y
# CONFIG_CMD_SETEXPR is not set
CONFIG_CMD_EXT4_WRITE=y
CONFIG_CMD_MTDPARTS=y
diff --git a/include/net.h b/include/net.h
index 5760685556..9c7199aca9 100644
--- a/include/net.h
+++ b/include/net.h
@@ -344,6 +344,7 @@ struct vlan_ethernet_hdr {
#define PROT_IP 0x0800 /* IP protocol */
#define PROT_ARP 0x0806 /* IP ARP protocol */
+#define PROT_WOL 0x0842 /* ether-wake WoL protocol */
#define PROT_RARP 0x8035 /* IP ARP protocol */
#define PROT_VLAN 0x8100 /* IEEE 802.1q protocol */
#define PROT_IPV6 0x86dd /* IPv6 over bluebook */
@@ -535,7 +536,7 @@ extern int net_restart_wrap; /* Tried all network devices */
enum proto_t {
BOOTP, RARP, ARP, TFTPGET, DHCP, PING, DNS, NFS, CDP, NETCONS, SNTP,
- TFTPSRV, TFTPPUT, LINKLOCAL, FASTBOOT
+ TFTPSRV, TFTPPUT, LINKLOCAL, FASTBOOT, WOL
};
extern char net_boot_file_name[1024];/* Boot File name */
diff --git a/net/Makefile b/net/Makefile
index 07466879f5..c3699d309d 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_CMD_PING) += ping.o
obj-$(CONFIG_CMD_RARP) += rarp.o
obj-$(CONFIG_CMD_SNTP) += sntp.o
obj-$(CONFIG_CMD_TFTPBOOT) += tftp.o
+obj-$(CONFIG_CMD_WOL) += wol.o
obj-$(CONFIG_UDP_FUNCTION_FASTBOOT) += fastboot.o
# Disable this warning as it is triggered by:
diff --git a/net/net.c b/net/net.c
index b4563a4cab..084269e31e 100644
--- a/net/net.c
+++ b/net/net.c
@@ -78,6 +78,12 @@
* - own IP address
* We want: - network time
* Next step: none
+ *
+ * WOL:
+ *
+ * Prerequisites: - own ethernet address
+ * We want: - magic packet or timeout
+ * Next step: none
*/
@@ -108,6 +114,9 @@
#if defined(CONFIG_CMD_SNTP)
#include "sntp.h"
#endif
+#if defined(CONFIG_CMD_WOL)
+#include "wol.h"
+#endif
/** BOOTP EXTENTIONS **/
@@ -514,6 +523,11 @@ restart:
case LINKLOCAL:
link_local_start();
break;
+#endif
+#if defined(CONFIG_CMD_WOL)
+ case WOL:
+ wol_start();
+ break;
#endif
default:
break;
@@ -1281,6 +1295,11 @@ void net_process_received_packet(uchar *in_packet, int len)
ntohs(ip->udp_src),
ntohs(ip->udp_len) - UDP_HDR_SIZE);
break;
+#ifdef CONFIG_CMD_WOL
+ case PROT_WOL:
+ wol_receive(ip, len);
+ break;
+#endif
}
}
diff --git a/net/wol.c b/net/wol.c
new file mode 100644
index 0000000000..b95b03ce5e
--- /dev/null
+++ b/net/wol.c
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2018 Lothar Felten, lothar.felten at gmail.com
+ */
+
+#include <common.h>
+#include <command.h>
+#include <net.h>
+#include <environment.h>
+#include "wol.h"
+
+static ulong wol_timeout = WOL_DEFAULT_TIMEOUT;
+
+/*
+ * Check incoming Wake-on-LAN packet for:
+ * - sync bytes
+ * - sixteen copies of the target MAC address
+ *
+ * @param wol Wake-on-LAN packet
+ * @param len Packet length
+ */
+static int wol_check_magic(struct wol_hdr *wol, unsigned int len)
+{
+ int i;
+
+ if (len < sizeof(struct wol_hdr))
+ return 0;
+
+ for (i = 0; i < WOL_SYNC_COUNT; i++)
+ if (wol->wol_sync[i] != WOL_SYNC_BYTE)
+ return 0;
+
+ for (i = 0; i < WOL_MAC_REPETITIONS; i++)
+ if (memcmp(&wol->wol_dest[i * ARP_HLEN],
+ net_ethaddr, ARP_HLEN) != 0)
+ return 0;
+
+ return 1;
+}
+
+void wol_receive(struct ip_udp_hdr *ip, unsigned int len)
+{
+ struct wol_hdr *wol;
+
+ wol = (struct wol_hdr *)ip;
+
+ if (!wol_check_magic(wol, len))
+ return;
+
+ /* save the optional password using the ether-wake formats */
+ /* don't check for exact length, the packet might have padding */
+ if (len >= (sizeof(struct wol_hdr) + WOL_PASSWORD_6B)) {
+ eth_env_set_enetaddr("wolpassword", wol->wol_passwd);
+ } else if (len >= (sizeof(struct wol_hdr) + WOL_PASSWORD_4B)) {
+ char buffer[16];
+ struct in_addr *ip = (struct in_addr *)(wol->wol_passwd);
+
+ ip_to_string(*ip, buffer);
+ env_set("wolpassword", buffer);
+ }
+ net_set_state(NETLOOP_SUCCESS);
+}
+
+static void wol_udp_handler(uchar *pkt, unsigned int dest, struct in_addr sip,
+ unsigned int src, unsigned int len)
+{
+ struct wol_hdr *wol;
+
+ wol = (struct wol_hdr *)pkt;
+
+ /* UDP destination port must be 0, 7 or 9 */
+ if (dest != 0 && dest != 7 && dest != 9)
+ return;
+
+ if (!wol_check_magic(wol, len))
+ return;
+
+ net_set_state(NETLOOP_SUCCESS);
+}
+
+void wol_set_timeout(ulong timeout)
+{
+ wol_timeout = timeout;
+}
+
+static void wol_timeout_handler(void)
+{
+ eth_halt();
+ net_set_state(NETLOOP_FAIL);
+}
+
+void wol_start(void)
+{
+ net_set_timeout_handler(wol_timeout, wol_timeout_handler);
+ net_set_udp_handler(wol_udp_handler);
+}
diff --git a/net/wol.h b/net/wol.h
new file mode 100644
index 0000000000..ebc81f24b6
--- /dev/null
+++ b/net/wol.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * wol - Wake-on-LAN
+ *
+ * Supports both Wake-on-LAN packet types:
+ * - EtherType 0x0842 packets
+ * - UDP packets on ports 0, 7 and 9.
+ *
+ * Copyright 2018 Lothar Felten, lothar.felten at gmail.com
+ */
+
+#if defined(CONFIG_CMD_WOL)
+
+#ifndef __WOL_H__
+#define __WOL_H__
+
+#include <net.h>
+
+/**********************************************************************/
+
+#define WOL_SYNC_BYTE 0xFF
+#define WOL_SYNC_COUNT 6
+#define WOL_MAC_REPETITIONS 16
+#define WOL_DEFAULT_TIMEOUT 5000
+#define WOL_PASSWORD_4B 4
+#define WOL_PASSWORD_6B 6
+
+/*
+ * Wake-on-LAN header
+ */
+struct wol_hdr {
+ u8 wol_sync[WOL_SYNC_COUNT]; /* sync bytes */
+ u8 wol_dest[WOL_MAC_REPETITIONS * ARP_HLEN]; /* 16x MAC */
+ u8 wol_passwd[0]; /* optional */
+};
+
+/*
+ * Initialize wol (beginning of netloop)
+ */
+void wol_start(void);
+
+/*
+ * Check incoming Wake-on-LAN packet for:
+ * - sync bytes
+ * - sixteen copies of the target MAC address
+ *
+ * Optionally store the four or six byte password in the environment
+ * variable "wolpassword"
+ *
+ * @param ip IP header in the packet
+ * @param len Packet length
+ */
+void wol_receive(struct ip_udp_hdr *ip, unsigned int len);
+
+/*
+ * Set the timeout for the reception of a Wake-on-LAN packet
+ *
+ * @param timeout in milliseconds
+ */
+void wol_set_timeout(ulong timeout);
+
+/**********************************************************************/
+
+#endif /* __WOL_H__ */
+#endif
--
2.14.1
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