Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

plugins/inputs/powerdns_recursor/protocol_v3.go

@@ -0,0 +1,91 @@
+package powerdns_recursor
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"time"
+
+	"github.com/influxdata/telegraf"
+)
+
+// V3 (4.6.0+) Protocol:
+// Standard unix stream socket
+// Synchronous request / response
+// Data structure:
+// status: uint32
+// dataLength: size_t
+// data: byte[dataLength]
+func gatherFromV3Server(address string, acc telegraf.Accumulator) error {
+	conn, err := net.Dial("unix", address)
+	if err != nil {
+		return err
+	}
+
+	defer conn.Close()
+
+	if err := conn.SetDeadline(time.Now().Add(defaultTimeout)); err != nil {
+		return err
+	}
+
+	// Write 4-byte response code.
+	if _, err = conn.Write([]byte{0, 0, 0, 0}); err != nil {
+		return err
+	}
+
+	command := []byte("get-all")
+
+	if err := writeNativeUIntToConn(conn, uint(len(command))); err != nil {
+		return err
+	}
+
+	if _, err = conn.Write(command); err != nil {
+		return err
+	}
+
+	// Now read the response.
+	status := make([]byte, 4)
+	n, err := conn.Read(status)
+	if err != nil {
+		return err
+	}
+	if n == 0 {
+		return errors.New("no status code received")
+	}
+
+	responseLength, err := readNativeUIntFromConn(conn)
+	if err != nil {
+		return err
+	}
+	if responseLength == 0 {
+		return errors.New("received data length was '0'")
+	}
+
+	// Don't allow more than 64kb of data to prevent DOS / issues
+	// with architecture mismatch. V2 protocol allowed for up to
+	// 16kb, so 64kb should give us a pretty good margin for anything
+	// that has been added since.
+	if responseLength > 64*1024 {
+		return fmt.Errorf("received data length was '%d', we only allow up to '%d'", responseLength, 64*1024)
+	}
+
+	data := make([]byte, responseLength)
+	n, err = conn.Read(data)
+	if err != nil {
+		return err
+	}
+	if uint(n) != responseLength {
+		return fmt.Errorf("no data received, expected '%v' bytes but got '%v'", responseLength, n)
+	}
+
+	// Process data
+	metrics := string(data)
+	fields := parseResponse(metrics)
+
+	// Add server socket as a tag
+	tags := map[string]string{"server": address}
+
+	acc.AddFields("powerdns_recursor", fields, tags)
+
+	return nil
+}