1 files changed, 131 insertions, 0 deletions
diff --git a/src/go/collectors/go.d.plugin/modules/openvpn_status_log/parser.go b/src/go/collectors/go.d.plugin/modules/openvpn_status_log/parser.go
new file mode 100644
index 000000000..c734fd5fb
--- /dev/null
+++ b/src/go/collectors/go.d.plugin/modules/openvpn_status_log/parser.go
@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package openvpn_status_log
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type clientInfo struct {
+	commonName     string
+	bytesReceived  int64
+	bytesSent      int64
+	connectedSince int64
+}
+
+func parse(path string) ([]clientInfo, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer func() { _ = f.Close() }()
+
+	sc := bufio.NewScanner(f)
+	_ = sc.Scan()
+	line := sc.Text()
+
+	if line == "OpenVPN CLIENT LIST" {
+		return parseV1(sc), nil
+	}
+	if strings.HasPrefix(line, "TITLE,OpenVPN") || strings.HasPrefix(line, "TITLE\tOpenVPN") {
+		return parseV2V3(sc), nil
+	}
+	if line == "OpenVPN STATISTICS" {
+		return parseStaticKey(sc), nil
+	}
+	return nil, fmt.Errorf("the status log file is invalid (%s)", path)
+}
+
+func parseV1(sc *bufio.Scanner) []clientInfo {
+	// https://github.com/OpenVPN/openvpn/blob/d5315a5d7400a26f1113bbc44766d49dd0c3688f/src/openvpn/multi.c#L836
+	var clients []clientInfo
+
+	for sc.Scan() {
+		if !strings.HasPrefix(sc.Text(), "Common Name") {
+			continue
+		}
+		for sc.Scan() && !strings.HasPrefix(sc.Text(), "ROUTING TABLE") {
+			parts := strings.Split(sc.Text(), ",")
+			if len(parts) != 5 {
+				continue
+			}
+
+			name := parts[0]
+			bytesRx, _ := strconv.ParseInt(parts[2], 10, 64)
+			bytesTx, _ := strconv.ParseInt(parts[3], 10, 64)
+			connSince, _ := time.Parse("Mon Jan 2 15:04:05 2006", parts[4])
+
+			clients = append(clients, clientInfo{
+				commonName:     name,
+				bytesReceived:  bytesRx,
+				bytesSent:      bytesTx,
+				connectedSince: connSince.Unix(),
+			})
+		}
+		break
+	}
+	return clients
+}
+
+func parseV2V3(sc *bufio.Scanner) []clientInfo {
+	// https://github.com/OpenVPN/openvpn/blob/d5315a5d7400a26f1113bbc44766d49dd0c3688f/src/openvpn/multi.c#L901
+	var clients []clientInfo
+	var sep string
+	if strings.IndexByte(sc.Text(), '\t') != -1 {
+		sep = "\t"
+	} else {
+		sep = ","
+	}
+
+	for sc.Scan() {
+		line := sc.Text()
+		if !strings.HasPrefix(line, "CLIENT_LIST") {
+			continue
+		}
+		parts := strings.Split(line, sep)
+		if len(parts) != 13 {
+			continue
+		}
+
+		name := parts[1]
+		bytesRx, _ := strconv.ParseInt(parts[5], 10, 64)
+		bytesTx, _ := strconv.ParseInt(parts[6], 10, 64)
+		connSince, _ := strconv.ParseInt(parts[8], 10, 64)
+
+		clients = append(clients, clientInfo{
+			commonName:     name,
+			bytesReceived:  bytesRx,
+			bytesSent:      bytesTx,
+			connectedSince: connSince,
+		})
+	}
+	return clients
+}
+
+func parseStaticKey(sc *bufio.Scanner) []clientInfo {
+	// https://github.com/OpenVPN/openvpn/blob/d5315a5d7400a26f1113bbc44766d49dd0c3688f/src/openvpn/sig.c#L283
+	var info clientInfo
+	for sc.Scan() {
+		line := sc.Text()
+		if !strings.HasPrefix(line, "TCP/UDP") {
+			continue
+		}
+		i := strings.IndexByte(line, ',')
+		if i == -1 || len(line) == i {
+			continue
+		}
+		bytes, _ := strconv.ParseInt(line[i+1:], 10, 64)
+		switch line[:i] {
+		case "TCP/UDP read bytes":
+			info.bytesReceived += bytes
+		case "TCP/UDP write bytes":
+			info.bytesSent += bytes
+		}
+	}
+	return []clientInfo{info}
+}