--- zzzz-none-000/linux-4.9.276/net/l2tp/l2tp_ppp.c	2021-07-20 14:21:16.000000000 +0000
+++ falcon-5530-750/linux-4.9.276/net/l2tp/l2tp_ppp.c	2023-04-05 08:19:02.000000000 +0000
@@ -181,6 +181,183 @@
 	return session;
 }
 
+#if IS_ENABLED(CONFIG_PPA)
+enum {
+	PPPOL2TP_GET_SESSION_ID = 1,
+	PPPOL2TP_GET_TUNNEL_ID,
+	PPPOL2TP_GET_BASEIF,
+	PPPOL2TP_GET_ADDR,
+	PPPOL2TP_GET_DMAC,
+	PPPOL2TP_GET_SADDR,
+	PPPOL2TP_GET_DADDR,
+};
+
+extern int32_t (*ppa_get_pppol2tp_info_fn)(struct net_device *dev, void *po, uint32_t pppol2tp_id, void *value);
+
+static void pppol2tp_getsaddr(struct net_device *dev, struct sock *sk_tun,
+			      u32 *outer_srcip)
+{
+	struct inet_sock *inet;
+	unsigned int src_ip;
+
+	inet = inet_sk(sk_tun);
+	src_ip = inet->inet_saddr;
+
+	*outer_srcip = src_ip;
+}
+
+static void pppol2tp_getdaddr(struct net_device *dev, struct sock *sk_tun,
+			      u32 *outer_dstip)
+{
+	struct inet_sock *inet;
+	unsigned int dst_ip;
+
+	inet = inet_sk(sk_tun);
+	dst_ip = inet->inet_daddr;
+
+	*outer_dstip = dst_ip;
+}
+
+static void pppol2tp_geteth(struct net_device *dev, struct sock *sk_tun,
+			    void *devname)
+{
+	struct inet_sock *inet;
+	struct net_device *phydev = NULL;
+	struct rtable *rt;
+
+	inet = inet_sk(sk_tun);
+
+	if (inet->inet_daddr) {
+		struct flowi fl = { .u.ip4 = { .daddr = inet->inet_daddr,
+					       .saddr = inet->inet_saddr,
+					       .flowi4_tos = RT_TOS(inet->tos),
+					       .flowi4_oif = sk_tun->sk_bound_dev_if,
+					       .flowi4_proto = sk_tun->sk_protocol } };
+		rt = ip_route_output_key(dev_net(dev), (struct flowi4 *)&fl);
+		if (rt) {
+			phydev = rt->dst.dev;
+			memcpy(devname, (phydev->name), sizeof(phydev->name));
+		}
+	}
+}
+
+static int pppol2tp_getdmac(struct net_device *dev, struct sock *sk_tun,
+			    u8 *mac)
+{
+	struct rtable *rt = NULL;
+	struct dst_entry *dst = NULL;
+	struct neighbour *neighbour = NULL;
+	struct inet_sock *inet;
+
+	inet = inet_sk(sk_tun);
+	dst = sk_tun->sk_dst_cache;
+	rt = (struct rtable *)__sk_dst_check(sk_tun, 0);
+	if (!rt) {
+		if (inet->inet_daddr) {
+			struct flowi f1 = { .u.ip4 = { .daddr = inet->inet_daddr,
+						       .saddr = inet->inet_saddr,
+						       .flowi4_tos = RT_TOS(inet->tos),
+						       .flowi4_proto = sk_tun->sk_protocol,
+						       .flowi4_flags = inet_sk_flowi_flags(sk_tun),
+						       .flowi4_oif = sk_tun->sk_bound_dev_if } };
+
+			rt = ip_route_output_key(dev_net(dev),
+						 (struct flowi4 *)&f1);
+			if (rt)
+				dst = &rt->dst;
+		}
+	}
+	dst = &rt->dst;
+	if (!dst)
+		goto MAC_ERROR;
+
+	neighbour = dst_neigh_lookup(dst, &inet->inet_daddr);
+	if (neighbour) {
+		if (neighbour->ha[0] != 0 || neighbour->ha[1] != 0 || neighbour->ha[2] != 0 || neighbour->ha[3] != 0 || neighbour->ha[4] != 0 || neighbour->ha[5] != 0)
+			memcpy(mac, (u8 *)(neighbour->ha), ETH_ALEN);
+		neigh_release(neighbour);
+	} else {
+		goto MAC_ERROR;
+	}
+
+	return 0;
+
+MAC_ERROR:
+	return -1;
+}
+
+static int get_pppol2tp_info(struct net_device *dev, void *po,
+			     unsigned int pppol2tp_id, void *value)
+{
+	struct pppol2tp_addr *pa;
+	struct pppol2tp_session *pls;
+	struct l2tp_session *session;
+	struct l2tp_tunnel *tunnel;
+	char devname[IFNAMSIZ];
+	struct net_device *pppol2tp_dev;
+	struct sock *sk_tun;
+	struct sock *sk;
+	struct inet_sock *inet;
+	int ret = 0;
+
+	if (!po)
+		return -1;
+
+	sk = (struct sock *)po;
+	session = pppol2tp_sock_to_session(sk);
+	if (!session)
+		return -1;
+
+	pls = l2tp_session_priv(session);
+	sk_tun = pls->tunnel_sock;
+	tunnel = l2tp_sock_to_tunnel(sk_tun);
+	if (!tunnel)
+		return -1;
+
+	inet = inet_sk(sk_tun);
+
+	pppol2tp_dev = dev_get_by_name(dev_net(dev), devname);
+	if (pppol2tp_dev)
+		dev_put(pppol2tp_dev);
+
+	switch (pppol2tp_id) {
+	case PPPOL2TP_GET_SESSION_ID:
+		*(u_int16_t *)value = session->peer_session_id;
+		break;
+	case PPPOL2TP_GET_TUNNEL_ID:
+		*(u_int16_t *)value = tunnel->peer_tunnel_id;
+		break;
+	case PPPOL2TP_GET_ADDR:
+		pa = (struct pppol2tp_addr *)value;
+		pa->fd = tunnel->fd;
+		pa->pid = pls->owner;
+		pa->s_tunnel = tunnel->tunnel_id;
+		pa->d_tunnel = tunnel->peer_tunnel_id;
+		pa->s_session = session->session_id;
+		pa->d_session = session->peer_session_id;
+		pa->addr.sin_family = AF_INET;
+		pa->addr.sin_port = inet->inet_dport;
+		pa->addr.sin_addr.s_addr = inet->inet_daddr;
+		break;
+	case PPPOL2TP_GET_BASEIF:
+		pppol2tp_geteth(dev, sk_tun, value);
+		break;
+	case PPPOL2TP_GET_DMAC:
+		ret = pppol2tp_getdmac(dev, sk_tun, (u8 *)value);
+		break;
+	case PPPOL2TP_GET_SADDR:
+		pppol2tp_getsaddr(dev, sk_tun, (u32 *)value);
+		break;
+	case PPPOL2TP_GET_DADDR:
+		pppol2tp_getdaddr(dev, sk_tun, (u32 *)value);
+		break;
+	default:
+		return -1;
+	}
+	return 0;
+}
+#endif /* CONFIG_PPA */
+
 /*****************************************************************************
  * Receive data handling
  *****************************************************************************/
@@ -1892,7 +2069,9 @@
 	if (err)
 		goto out_unregister_pppox;
 #endif
-
+#if IS_ENABLED(CONFIG_PPA)
+	ppa_get_pppol2tp_info_fn = get_pppol2tp_info;
+#endif
 	pr_info("PPPoL2TP kernel driver, %s\n", PPPOL2TP_DRV_VERSION);
 
 out:
@@ -1911,6 +2090,9 @@
 
 static void __exit pppol2tp_exit(void)
 {
+#if IS_ENABLED(CONFIG_PPA)
+	ppa_get_pppol2tp_info_fn = NULL;
+#endif
 #ifdef CONFIG_L2TP_V3
 	l2tp_nl_unregister_ops(L2TP_PWTYPE_PPP);
 #endif