From 69ff7cede511457837ed93659b38804841bd7dc7 Mon Sep 17 00:00:00 2001
From: Riya Singhal <rsinghal@redhat.com>
Date: Fri, 15 Dec 2023 18:37:49 +0530
Subject: [PATCH] cephfs: fix fetchIP to support more formats

Signed-off-by: Riya Singhal <rsinghal@redhat.com>
(cherry picked from commit bee77f7fac51a733063c59b0c635d62bc8d6b3a5)
(cherry picked from commit 03087481e77817ef220ad2cdf492ef2eacd807b4)
---
 internal/csi-addons/networkfence/fencing.go   | 24 +++++++++++++++----
 .../csi-addons/networkfence/fencing_test.go   |  5 ++++
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/internal/csi-addons/networkfence/fencing.go b/internal/csi-addons/networkfence/fencing.go
index d8361e55c2b..5554a0cd33d 100644
--- a/internal/csi-addons/networkfence/fencing.go
+++ b/internal/csi-addons/networkfence/fencing.go
@@ -22,6 +22,7 @@ import (
 	"errors"
 	"fmt"
 	"net"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -210,11 +211,24 @@ func (ac *activeClient) fetchIP() (string, error) {
 	// example: "inst": "client.4305 172.21.9.34:0/422650892",
 	// then returning value will be 172.21.9.34
 	clientInfo := ac.Inst
-	parts := strings.Fields(clientInfo)
-	if len(parts) >= 2 {
-		lastColonIndex := strings.LastIndex(parts[1], ":")
-		firstPart := parts[1][:lastColonIndex]
-		ip := net.ParseIP(firstPart)
+
+	// Attempt to extract the IP address using a regular expression
+	// the regular expression aims to match either a complete IPv6
+	// address or a complete IPv4 address follows by any prefix (v1 or v2)
+	// if exists
+	// (?:v[0-9]+:): this allows for an optional prefix starting with "v"
+	// followed by one or more digits and a colon.
+	// The ? outside the group makes the entire prefix section optional.
+	// (?:[0-9a-fA-F]{1,4}:){7}[0-9a-fA-F]{1,4}: this allows to check for
+	// standard IPv6 address.
+	// |: Alternation operator to allow matching either the IPv6 pattern
+	// with a prefix or the IPv4 pattern.
+	// '(?:\d+\.){3}\d+: This part matches a standard IPv4 address.
+	re := regexp.MustCompile(`(?:v[0-9]+:)?([0-9a-fA-F]{1,4}(:[0-9a-fA-F]{1,4}){7}|(?:\d+\.){3}\d+)`)
+	ipMatches := re.FindStringSubmatch(clientInfo)
+
+	if len(ipMatches) > 0 {
+		ip := net.ParseIP(ipMatches[1])
 		if ip != nil {
 			return ip.String(), nil
 		}
diff --git a/internal/csi-addons/networkfence/fencing_test.go b/internal/csi-addons/networkfence/fencing_test.go
index 40242cf7907..26aab00f606 100644
--- a/internal/csi-addons/networkfence/fencing_test.go
+++ b/internal/csi-addons/networkfence/fencing_test.go
@@ -73,6 +73,11 @@ func TestFetchIP(t *testing.T) {
 			expectedIP:  "2001:db8:85a3::8a2e:370:7334",
 			expectedErr: false,
 		},
+		{
+			clientInfo:  "client.24152 v1:100.64.0.7:0/3658550259",
+			expectedIP:  "100.64.0.7",
+			expectedErr: false,
+		},
 		{
 			clientInfo:  "",
 			expectedIP:  "",