From c14292dc508fddb334c30307bae46943ced78092 Mon Sep 17 00:00:00 2001
From: ionutboangiu <ionut.boangiu@itsyscom.com>
Date: Thu, 19 Feb 2026 20:11:43 +0200
Subject: [PATCH] radius: support reading vendor-specific attributes

handles paths with 2 elements the same way radAppendAttributes does
e.g. *req.Microsoft.MS-CHAP2-Response

Ref: #4962
---
 agents/librad.go      | 12 +++++++++---
 agents/librad_test.go | 15 ++++++++++++++-
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/agents/librad.go b/agents/librad.go
index 78caf44e8..fc82829ca 100644
--- a/agents/librad.go
+++ b/agents/librad.go
@@ -72,7 +72,7 @@ func (pk *radiusDP) String() string {
 
 // FieldAsInterface is part of utils.DataProvider interface
 func (pk *radiusDP) FieldAsInterface(fldPath []string) (data any, err error) {
-	if len(fldPath) != 1 {
+	if len(fldPath) == 0 || len(fldPath) > 2 {
 		return nil, utils.ErrNotFound
 	}
 	if data, err = pk.cache.FieldAsInterface(fldPath); err != nil {
@@ -83,8 +83,14 @@ func (pk *radiusDP) FieldAsInterface(fldPath []string) (data any, err error) {
 	} else {
 		return // data found in cache
 	}
-	if len(pk.req.AttributesWithName(fldPath[0], "")) != 0 {
-		data = pk.req.AttributesWithName(fldPath[0], "")[0].GetStringValue()
+	var attrName, vendorName string
+	if len(fldPath) == 2 {
+		vendorName, attrName = fldPath[0], fldPath[1]
+	} else {
+		attrName = fldPath[0]
+	}
+	if avps := pk.req.AttributesWithName(attrName, vendorName); len(avps) != 0 {
+		data = avps[0].GetStringValue()
 	}
 	pk.cache.Set(fldPath, data)
 	return
diff --git a/agents/librad_test.go b/agents/librad_test.go
index a97d4f9fd..a36b747cc 100644
--- a/agents/librad_test.go
+++ b/agents/librad_test.go
@@ -166,9 +166,22 @@ func TestLibradRadiusDPString(t *testing.T) {
 	}
 }
 
+func TestRadiusDPFieldAsInterfaceVSA(t *testing.T) {
+	pkt := radigo.NewPacket(radigo.AccountingRequest, 1, dictRad, coder, "CGRateS.org")
+	if err := pkt.AddAVPWithName("Cisco-NAS-Port", "CGR1", "Cisco"); err != nil {
+		t.Fatal(err)
+	}
+	dp := newRADataProvider(pkt)
+	if data, err := dp.FieldAsInterface([]string{"Cisco", "Cisco-NAS-Port"}); err != nil {
+		t.Error(err)
+	} else if data != "CGR1" {
+		t.Errorf("Expected CGR1, got: %v", data)
+	}
+}
+
 func TestLibradFieldAsInterfaceWithInvalidPathLength(t *testing.T) {
 	pk := &radiusDP{}
-	fldPath := []string{"attribute1", "attribute2"}
+	fldPath := []string{"vendor", "attribute", "extra"}
 	data, err := pk.FieldAsInterface(fldPath)
 	if err != utils.ErrNotFound {
 		t.Errorf("Expected ErrNotFound error, got: %v", err)