3.21.8

core/ping.go

@@ -0,0 +1,87 @@
+package openp2p
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"time"
+
+	"golang.org/x/net/icmp"
+	"golang.org/x/net/ipv4"
+)
+
+// 定义ICMP回显请求和应答的结构
+type ICMPMessage struct {
+	Type     uint8
+	Code     uint8
+	Checksum uint16
+	Ident    uint16
+	Seq      uint16
+	Data     []byte
+}
+
+// Ping sends an ICMP Echo request to the specified host and returns the response time.
+func Ping(host string) (time.Duration, error) {
+	// Resolve the IP address of the host
+	ipAddr, err := net.ResolveIPAddr("ip4", host)
+	if err != nil {
+		return 0, fmt.Errorf("failed to resolve host: %v", err)
+	}
+
+	// Create an ICMP listener
+	conn, err := net.ListenPacket("ip4:icmp", "0.0.0.0")
+	if err != nil {
+		return 0, fmt.Errorf("failed to create ICMP connection: %v", err)
+	}
+	defer conn.Close()
+
+	// Create an ICMP Echo request message
+	message := icmp.Message{
+		Type: ipv4.ICMPTypeEcho,
+		Code: 0,
+		Body: &icmp.Echo{
+			ID:   os.Getpid() & 0xffff,
+			Seq:  1,
+			Data: []byte("HELLO-R-U-THERE"),
+		},
+	}
+
+	// Marshal the message into binary form
+	messageBytes, err := message.Marshal(nil)
+	if err != nil {
+		return 0, fmt.Errorf("failed to marshal ICMP message: %v", err)
+	}
+
+	// Send the ICMP Echo request
+	start := time.Now()
+	if _, err := conn.WriteTo(messageBytes, ipAddr); err != nil {
+		return 0, fmt.Errorf("failed to send ICMP request: %v", err)
+	}
+
+	// Set a deadline for the response
+	err = conn.SetReadDeadline(time.Now().Add(3 * time.Second))
+	if err != nil {
+		return 0, fmt.Errorf("failed to set read deadline: %v", err)
+	}
+
+	// Read the ICMP response
+	response := make([]byte, 1500)
+	n, _, err := conn.ReadFrom(response)
+	if err != nil {
+		return 0, fmt.Errorf("failed to read ICMP response: %v", err)
+	}
+
+	// Parse the ICMP response message
+	parsedMessage, err := icmp.ParseMessage(ipv4.ICMPTypeEchoReply.Protocol(), response[:n])
+	if err != nil {
+		return 0, fmt.Errorf("failed to parse ICMP response: %v", err)
+	}
+
+	// Check if the response is an Echo reply
+	if parsedMessage.Type == ipv4.ICMPTypeEchoReply {
+		duration := time.Since(start)
+		return duration, nil
+	} else {
+		return 0, fmt.Errorf("unexpected ICMP message: %+v", parsedMessage)
+	}
+}