net: ping6: Add ping6 command

Implement ping6 command to ping hosts using IPv6. It works the same way as
an ordinary ping command. There is no ICMP request so it is not possible
to ping our host. This patch adds options in Kconfig and Makefile to
build ping6 command.

Series-changes: 3
- Added structures and functions descriptions
- Added to ping6_receive() return value instead of void

Series-changes: 4
- Fixed structures and functions description style

Signed-off-by: Viacheslav Mitrofanov <v.v.mitrofanov@yadro.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

cmd/Kconfig

@@ -1847,6 +1847,13 @@ config CMD_PING
 	help
 	  Send ICMP ECHO_REQUEST to network host
 
+config CMD_PING6
+	bool "ping6"
+	depends on IPV6
+	default y if (CMD_PING && IPV6)
+	help
+	  Send ICMPv6 ECHO_REQUEST to network host
+
 config CMD_CDP
 	bool "cdp"
 	help

cmd/net.c

@@ -403,6 +403,32 @@ U_BOOT_CMD(
 );
 #endif
 
+#if IS_ENABLED(CONFIG_CMD_PING6)
+int do_ping6(struct cmd_tbl *cmdtp, int flag, int argc, char * const argv[])
+{
+	if (string_to_ip6(argv[1], strlen(argv[1]), &net_ping_ip6))
+		return CMD_RET_USAGE;
+
+	use_ip6 = true;
+	if (net_loop(PING6) < 0) {
+		use_ip6 = false;
+		printf("ping6 failed; host %pI6c is not alive\n",
+		       &net_ping_ip6);
+		return 1;
+	}
+
+	use_ip6 = false;
+	printf("host %pI6c is alive\n", &net_ping_ip6);
+	return 0;
+}
+
+U_BOOT_CMD(
+	ping6,  2,      1,      do_ping6,
+	"send ICMPv6 ECHO_REQUEST to network host",
+	"pingAddress"
+);
+#endif /* CONFIG_CMD_PING6 */
+
 #if defined(CONFIG_CMD_CDP)
 
 static void cdp_update_env(void)

include/net.h

@@ -560,8 +560,8 @@ extern ushort		net_native_vlan;	/* Our Native VLAN */
 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, WOL, UDP, NCSI, WGET
+	BOOTP, RARP, ARP, TFTPGET, DHCP, PING, PING6, DNS, NFS, CDP, NETCONS,
+	SNTP, TFTPSRV, TFTPPUT, LINKLOCAL, FASTBOOT, WOL, UDP, NCSI, WGET
 };
 
 extern char	net_boot_file_name[1024];/* Boot File name */

include/net6.h

@@ -172,6 +172,7 @@ extern struct in6_addr net_ip6;	/* Our IPv6 addr (0 = unknown) */
 extern struct in6_addr net_link_local_ip6;	/* Our link local IPv6 addr */
 extern u32 net_prefix_length;	/* Our prefixlength (0 = unknown) */
 extern struct in6_addr net_server_ip6;	/* Server IPv6 addr (0 = unknown) */
+extern struct in6_addr net_ping_ip6; /* the ipv6 address to ping */
 extern bool use_ip6;
 
 #if IS_ENABLED(CONFIG_IPV6)
@@ -403,4 +404,29 @@ static inline void net_copy_ip6(void *to, const void *from)
 }
 #endif
 
+#if IS_ENABLED(CONFIG_CMD_PING6)
+/* Send ping requset */
+void ping6_start(void);
+
+/**
+ * ping6_receive() - Handle reception of ICMPv6 echo request/reply
+ *
+ * @et:		pointer to incoming patcket
+ * @ip6:	pointer to IPv6 protocol
+ * @len:	packet length
+ * Return: 0 if success, -EINVAL in case of failure during reception
+ */
+int ping6_receive(struct ethernet_hdr *et, struct ip6_hdr *ip6, int len);
+#else
+static inline void ping6_start(void)
+{
+}
+
+static inline
+int ping6_receive(struct ethernet_hdr *et, struct ip6_hdr *ip6, int len)
+{
+	return -EINVAL;
+}
+#endif /* CONFIG_CMD_PING6 */
+
 #endif /* __NET6_H__ */

net/Makefile

@@ -25,6 +25,7 @@ obj-$(CONFIG_NET)      += net.o
 obj-$(CONFIG_IPV6)     += net6.o
 obj-$(CONFIG_CMD_NFS)  += nfs.o
 obj-$(CONFIG_CMD_PING) += ping.o
+obj-$(CONFIG_CMD_PING6) += ping6.o
 obj-$(CONFIG_CMD_PCAP) += pcap.o
 obj-$(CONFIG_CMD_RARP) += rarp.o
 obj-$(CONFIG_CMD_SNTP) += sntp.o

net/net.c

@@ -525,6 +525,11 @@ restart:
 			ping_start();
 			break;
 #endif
+#if defined(CONFIG_CMD_PING6)
+		case PING6:
+			ping6_start();
+			break;
+#endif
 #if defined(CONFIG_CMD_NFS) && !defined(CONFIG_SPL_BUILD)
 		case NFS:
 			nfs_start();
@@ -1434,6 +1439,14 @@ static int net_check_prereq(enum proto_t protocol)
 		}
 		goto common;
 #endif
+#if defined(CONFIG_CMD_PING6)
+	case PING6:
+		if (ip6_is_unspecified_addr(&net_ping_ip6)) {
+			puts("*** ERROR: ping address not given\n");
+			return 1;
+		}
+		goto common;
+#endif
 #if defined(CONFIG_CMD_DNS)
 	case DNS:
 		if (net_dns_server.s_addr == 0) {

net/net6.c

@@ -404,6 +404,10 @@ int net_ip6_handler(struct ethernet_hdr *et, struct ip6_hdr *ip6, int len)
 			return -EINVAL;
 
 		switch (icmp->icmp6_type) {
+		case IPV6_ICMP_ECHO_REQUEST:
+		case IPV6_ICMP_ECHO_REPLY:
+			ping6_receive(et, ip6, len);
+			break;
 		case IPV6_NDISC_NEIGHBOUR_SOLICITATION:
 		case IPV6_NDISC_NEIGHBOUR_ADVERTISEMENT:
 			ndisc_receive(et, ip6, len);

net/ping6.c

@@ -0,0 +1,118 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2013 Allied Telesis Labs NZ
+ * Chris Packham, <judge.packham@gmail.com>
+ *
+ * Copyright (C) 2022 YADRO
+ * Viacheslav Mitrofanov <v.v.mitrofanov@yadro.com>
+ */
+
+/* Simple ping6 implementation */
+
+#include <common.h>
+#include <net.h>
+#include <net6.h>
+#include "ndisc.h"
+
+static ushort seq_no;
+
+/* the ipv6 address to ping */
+struct in6_addr net_ping_ip6;
+
+int
+ip6_make_ping(uchar *eth_dst_addr, struct in6_addr *neigh_addr, uchar *pkt)
+{
+	struct echo_msg *msg;
+	u16 len;
+	u16 csum_p;
+	uchar *pkt_old = pkt;
+
+	len = sizeof(struct echo_msg);
+
+	pkt += net_set_ether(pkt, eth_dst_addr, PROT_IP6);
+	pkt += ip6_add_hdr(pkt, &net_ip6, neigh_addr, PROT_ICMPV6,
+			   IPV6_NDISC_HOPLIMIT, len);
+
+	/* ICMPv6 - Echo */
+	msg = (struct echo_msg *)pkt;
+	msg->icmph.icmp6_type = IPV6_ICMP_ECHO_REQUEST;
+	msg->icmph.icmp6_code = 0;
+	msg->icmph.icmp6_cksum = 0;
+	msg->icmph.icmp6_identifier = 0;
+	msg->icmph.icmp6_sequence = htons(seq_no++);
+	msg->id = msg->icmph.icmp6_identifier;	/* these seem redundant */
+	msg->sequence = msg->icmph.icmp6_sequence;
+
+	/* checksum */
+	csum_p = csum_partial((u8 *)msg, len, 0);
+	msg->icmph.icmp6_cksum = csum_ipv6_magic(&net_ip6, neigh_addr, len,
+						 PROT_ICMPV6, csum_p);
+
+	pkt += len;
+
+	return pkt - pkt_old;
+}
+
+int ping6_send(void)
+{
+	uchar *pkt;
+	static uchar mac[6];
+
+	/* always send neighbor solicit */
+
+	memcpy(mac, net_null_ethaddr, 6);
+
+	net_nd_sol_packet_ip6 = net_ping_ip6;
+	net_nd_packet_mac = mac;
+
+	pkt = net_nd_tx_packet;
+	pkt += ip6_make_ping(mac, &net_ping_ip6, pkt);
+
+	/* size of the waiting packet */
+	net_nd_tx_packet_size = (pkt - net_nd_tx_packet);
+
+	/* and do the ARP request */
+	net_nd_try = 1;
+	net_nd_timer_start = get_timer(0);
+	ndisc_request();
+	return 1;		/* waiting */
+}
+
+static void ping6_timeout(void)
+{
+	eth_halt();
+	net_set_state(NETLOOP_FAIL);	/* we did not get the reply */
+}
+
+void ping6_start(void)
+{
+	printf("Using %s device\n", eth_get_name());
+	net_set_timeout_handler(10000UL, ping6_timeout);
+
+	ping6_send();
+}
+
+int ping6_receive(struct ethernet_hdr *et, struct ip6_hdr *ip6, int len)
+{
+	struct icmp6hdr *icmp =
+	    (struct icmp6hdr *)(((uchar *)ip6) + IP6_HDR_SIZE);
+	struct in6_addr src_ip;
+
+	switch (icmp->icmp6_type) {
+	case IPV6_ICMP_ECHO_REPLY:
+		src_ip = ip6->saddr;
+		if (memcmp(&net_ping_ip6, &src_ip, sizeof(struct in6_addr)))
+			return -EINVAL;
+		net_set_state(NETLOOP_SUCCESS);
+		break;
+	case IPV6_ICMP_ECHO_REQUEST:
+		/* ignore for now.... */
+		debug("Got ICMPv6 ECHO REQUEST from %pI6c\n", &ip6->saddr);
+		return -EINVAL;
+	default:
+		debug("Unexpected ICMPv6 type 0x%x\n", icmp->icmp6_type);
+		return -EINVAL;
+	}
+
+	return 0;
+}