l2tp: Update PPP-over-L2TP driver to work over L2TPv3

This patch makes changes to the L2TP PPP code for L2TPv3. The existing code has some assumptions about the L2TP header which are broken by L2TPv3. Also the sockaddr_pppol2tp structure of the original code is too small to support the increased size of the L2TPv3 tunnel and session id, so a new sockaddr_pppol2tpv3 structure is needed. In the socket calls, the size of this structure is used to tell if the operation is for L2TPv2 or L2TPv3. Signed-off-by: James Chapman <jchapman@katalix.com> Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>

l2tp: Update PPP-over-L2TP driver to work over L2TPv3
This patch makes changes to the L2TP PPP code for L2TPv3. The existing code has some assumptions about the L2TP header which are broken by L2TPv3. Also the sockaddr_pppol2tp structure of the original code is too small to support the increased size of the L2TPv3 tunnel and session id, so a new sockaddr_pppol2tpv3 structure is needed. In the socket calls, the size of this structure is used to tell if the operation is for L2TPv2 or L2TPv3. Signed-off-by: James Chapman <jchapman@katalix.com> Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
James Chapman · David S. Miller
1 parent f7faffa3ff
Showing 3 changed files with 97 additions and 46 deletions Side-by-side Diff
include/linux/if_pppol2tp.h
include/linux/if_pppox.h
net/l2tp/l2tp_ppp.c
@@ -35,6 +35,20 @@
 	__u16 d_tunnel, d_session;	/* For sending outgoing packets */
 };
  
+/* The L2TPv3 protocol changes tunnel and session ids from 16 to 32
+ * bits. So we need a different sockaddr structure.
+ */
+struct pppol2tpv3_addr {
+	pid_t	pid;			/* pid that owns the fd.
+					 * 0 => current */
+	int	fd;			/* FD of UDP or IP socket to use */
+
+	struct sockaddr_in addr;	/* IP address and port to send to */
+
+	__u32 s_tunnel, s_session;	/* For matching incoming packets */
+	__u32 d_tunnel, d_session;	/* For sending outgoing packets */
+};
+
 /* Socket options:
  * DEBUG	- bitmask of debug message categories
  * SENDSEQ	- 0 => don't send packets with sequence numbers
@@ -72,6 +72,15 @@
 	struct pppol2tp_addr pppol2tp;
 }__attribute__ ((packed));
  
+/* The L2TPv3 protocol changes tunnel and session ids from 16 to 32
+ * bits. So we need a different sockaddr structure.
+ */
+struct sockaddr_pppol2tpv3 {
+	sa_family_t     sa_family;      /* address family, AF_PPPOX */
+	unsigned int    sa_protocol;    /* protocol identifier */
+	struct pppol2tpv3_addr pppol2tp;
+} __attribute__ ((packed));
+
 /*********************************************************************
  *
  * ioctl interface for defining forwarding of connections
@@ -291,17 +291,6 @@
  * Transmit handling
  ***********************************************************************/
  
-/* Tell how big L2TP headers are for a particular session. This
- * depends on whether sequence numbers are being used.
- */
-static inline int pppol2tp_l2tp_header_len(struct l2tp_session *session)
-{
-	if (session->send_seq)
-		return PPPOL2TP_L2TP_HDR_SIZE_SEQ;
-
-	return PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
-}
-
 /* This is the sendmsg for the PPPoL2TP pppol2tp_session socket.  We come here
  * when a user application does a sendmsg() on the session socket. L2TP and
  * PPP headers must be inserted into the user's data.
@@ -394,7 +383,6 @@
 	static const u8 ppph[2] = { 0xff, 0x03 };
 	struct sock *sk = (struct sock *) chan->private;
 	struct sock *sk_tun;
-	int hdr_len;
 	struct l2tp_session *session;
 	struct l2tp_tunnel *tunnel;
 	struct pppol2tp_session *ps;
@@ -417,9 +405,6 @@
 	if (tunnel == NULL)
 		goto abort_put_sess;
  
-	/* What header length is configured for this session? */
-	hdr_len = pppol2tp_l2tp_header_len(session);
-
 	old_headroom = skb_headroom(skb);
 	if (skb_cow_head(skb, sizeof(ppph)))
 		goto abort_put_sess_tun;
@@ -432,7 +417,7 @@
 	skb->data[0] = ppph[0];
 	skb->data[1] = ppph[1];
  
-	l2tp_xmit_skb(session, skb, hdr_len);
+	l2tp_xmit_skb(session, skb, session->hdr_len);
  
 	sock_put(sk_tun);
 	sock_put(sk);
@@ -615,6 +600,7 @@
 {
 	struct sock *sk = sock->sk;
 	struct sockaddr_pppol2tp *sp = (struct sockaddr_pppol2tp *) uservaddr;
+	struct sockaddr_pppol2tpv3 *sp3 = (struct sockaddr_pppol2tpv3 *) uservaddr;
 	struct pppox_sock *po = pppox_sk(sk);
 	struct l2tp_session *session = NULL;
 	struct l2tp_tunnel *tunnel;
@@ -622,6 +608,10 @@
 	struct dst_entry *dst;
 	struct l2tp_session_cfg cfg = { 0, };
 	int error = 0;
+	u32 tunnel_id, peer_tunnel_id;
+	u32 session_id, peer_session_id;
+	int ver = 2;
+	int fd;
  
 	lock_sock(sk);
  
  
  
  
  
@@ -639,21 +629,40 @@
 	if (sk->sk_user_data)
 		goto end; /* socket is already attached */
  
-	/* Don't bind if s_tunnel is 0 */
+	/* Get params from socket address. Handle L2TPv2 and L2TPv3 */
+	if (sockaddr_len == sizeof(struct sockaddr_pppol2tp)) {
+		fd = sp->pppol2tp.fd;
+		tunnel_id = sp->pppol2tp.s_tunnel;
+		peer_tunnel_id = sp->pppol2tp.d_tunnel;
+		session_id = sp->pppol2tp.s_session;
+		peer_session_id = sp->pppol2tp.d_session;
+	} else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpv3)) {
+		ver = 3;
+		fd = sp3->pppol2tp.fd;
+		tunnel_id = sp3->pppol2tp.s_tunnel;
+		peer_tunnel_id = sp3->pppol2tp.d_tunnel;
+		session_id = sp3->pppol2tp.s_session;
+		peer_session_id = sp3->pppol2tp.d_session;
+	} else {
+		error = -EINVAL;
+		goto end; /* bad socket address */
+	}
+
+	/* Don't bind if tunnel_id is 0 */
 	error = -EINVAL;
-	if (sp->pppol2tp.s_tunnel == 0)
+	if (tunnel_id == 0)
 		goto end;
  
-	/* Special case: create tunnel context if s_session and
-	 * d_session is 0. Otherwise look up tunnel using supplied
+	/* Special case: create tunnel context if session_id and
+	 * peer_session_id is 0. Otherwise look up tunnel using supplied
 	 * tunnel id.
 	 */
-	if ((sp->pppol2tp.s_session == 0) && (sp->pppol2tp.d_session == 0)) {
-		error = l2tp_tunnel_create(sock_net(sk), sp->pppol2tp.fd, 2, sp->pppol2tp.s_tunnel, sp->pppol2tp.d_tunnel, NULL, &tunnel);
+	if ((session_id == 0) && (peer_session_id == 0)) {
+		error = l2tp_tunnel_create(sock_net(sk), fd, ver, tunnel_id, peer_tunnel_id, NULL, &tunnel);
 		if (error < 0)
 			goto end;
 	} else {
-		tunnel = l2tp_tunnel_find(sock_net(sk), sp->pppol2tp.s_tunnel);
+		tunnel = l2tp_tunnel_find(sock_net(sk), tunnel_id);
  
 		/* Error if we can't find the tunnel */
 		error = -ENOENT;
  
  
@@ -670,20 +679,21 @@
  
 	/* Check that this session doesn't already exist */
 	error = -EEXIST;
-	session = l2tp_session_find(sock_net(sk), tunnel, sp->pppol2tp.s_session);
+	session = l2tp_session_find(sock_net(sk), tunnel, session_id);
 	if (session != NULL)
 		goto end;
  
-	/* Default MTU must allow space for UDP/L2TP/PPP
-	 * headers.
-	 */
-	cfg.mtu = cfg.mru = 1500 - PPPOL2TP_HEADER_OVERHEAD;
+	/* Default MTU values. */
+	if (cfg.mtu == 0)
+		cfg.mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD;
+	if (cfg.mru == 0)
+		cfg.mru = cfg.mtu;
 	cfg.debug = tunnel->debug;
  
 	/* Allocate and initialize a new session context. */
 	session = l2tp_session_create(sizeof(struct pppol2tp_session),
-				      tunnel, sp->pppol2tp.s_session,
-				      sp->pppol2tp.d_session, &cfg);
+				      tunnel, session_id,
+				      peer_session_id, &cfg);
 	if (session == NULL) {
 		error = -ENOMEM;
 		goto end;
@@ -756,8 +766,7 @@
 static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
 			    int *usockaddr_len, int peer)
 {
-	int len = sizeof(struct sockaddr_pppol2tp);
-	struct sockaddr_pppol2tp sp;
+	int len = 0;
 	int error = 0;
 	struct l2tp_session *session;
 	struct l2tp_tunnel *tunnel;
  
@@ -783,21 +792,40 @@
 		goto end_put_sess;
 	}
  
-	memset(&sp, 0, len);
-	sp.sa_family	= AF_PPPOX;
-	sp.sa_protocol	= PX_PROTO_OL2TP;
-	sp.pppol2tp.fd  = tunnel->fd;
-	sp.pppol2tp.pid = pls->owner;
-	sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
-	sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
-	sp.pppol2tp.s_session = session->session_id;
-	sp.pppol2tp.d_session = session->peer_session_id;
 	inet = inet_sk(sk);
-	sp.pppol2tp.addr.sin_family = AF_INET;
-	sp.pppol2tp.addr.sin_port = inet->inet_dport;
-	sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
-
-	memcpy(uaddr, &sp, len);
+	if (tunnel->version == 2) {
+		struct sockaddr_pppol2tp sp;
+		len = sizeof(sp);
+		memset(&sp, 0, len);
+		sp.sa_family	= AF_PPPOX;
+		sp.sa_protocol	= PX_PROTO_OL2TP;
+		sp.pppol2tp.fd  = tunnel->fd;
+		sp.pppol2tp.pid = pls->owner;
+		sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
+		sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
+		sp.pppol2tp.s_session = session->session_id;
+		sp.pppol2tp.d_session = session->peer_session_id;
+		sp.pppol2tp.addr.sin_family = AF_INET;
+		sp.pppol2tp.addr.sin_port = inet->inet_dport;
+		sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
+		memcpy(uaddr, &sp, len);
+	} else if (tunnel->version == 3) {
+		struct sockaddr_pppol2tpv3 sp;
+		len = sizeof(sp);
+		memset(&sp, 0, len);
+		sp.sa_family	= AF_PPPOX;
+		sp.sa_protocol	= PX_PROTO_OL2TP;
+		sp.pppol2tp.fd  = tunnel->fd;
+		sp.pppol2tp.pid = pls->owner;
+		sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
+		sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
+		sp.pppol2tp.s_session = session->session_id;
+		sp.pppol2tp.d_session = session->peer_session_id;
+		sp.pppol2tp.addr.sin_family = AF_INET;
+		sp.pppol2tp.addr.sin_port = inet->inet_dport;
+		sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
+		memcpy(uaddr, &sp, len);
+	}
  
 	*usockaddr_len = len;
...	...	@@ -35,6 +35,20 @@
35	35	__u16 d_tunnel, d_session; /* For sending outgoing packets */
36	36	};
37	37
	38	+/* The L2TPv3 protocol changes tunnel and session ids from 16 to 32
	39	+ * bits. So we need a different sockaddr structure.
	40	+ */
	41	+struct pppol2tpv3_addr {
	42	+ pid_t pid; /* pid that owns the fd.
	43	+ * 0 => current */
	44	+ int fd; /* FD of UDP or IP socket to use */
	45	+
	46	+ struct sockaddr_in addr; /* IP address and port to send to */
	47	+
	48	+ __u32 s_tunnel, s_session; /* For matching incoming packets */
	49	+ __u32 d_tunnel, d_session; /* For sending outgoing packets */
	50	+};
	51	+
38	52	/* Socket options:
39	53	* DEBUG - bitmask of debug message categories
40	54	* SENDSEQ - 0 => don't send packets with sequence numbers
...	...	@@ -72,6 +72,15 @@
72	72	struct pppol2tp_addr pppol2tp;
73	73	}__attribute__ ((packed));
74	74
	75	+/* The L2TPv3 protocol changes tunnel and session ids from 16 to 32
	76	+ * bits. So we need a different sockaddr structure.
	77	+ */
	78	+struct sockaddr_pppol2tpv3 {
	79	+ sa_family_t sa_family; /* address family, AF_PPPOX */
	80	+ unsigned int sa_protocol; /* protocol identifier */
	81	+ struct pppol2tpv3_addr pppol2tp;
	82	+} __attribute__ ((packed));
	83	+
75	84	/*********************************************************************
76	85	*
77	86	* ioctl interface for defining forwarding of connections
...	...	@@ -291,17 +291,6 @@
291	291	* Transmit handling
292	292	***********************************************************************/
293	293
294		-/* Tell how big L2TP headers are for a particular session. This
295		- * depends on whether sequence numbers are being used.
296		- */
297		-static inline int pppol2tp_l2tp_header_len(struct l2tp_session *session)
298		-{
299		- if (session->send_seq)
300		- return PPPOL2TP_L2TP_HDR_SIZE_SEQ;
301		-
302		- return PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
303		-}
304		-
305	294	/* This is the sendmsg for the PPPoL2TP pppol2tp_session socket. We come here
306	295	* when a user application does a sendmsg() on the session socket. L2TP and
307	296	* PPP headers must be inserted into the user's data.
...	...	@@ -394,7 +383,6 @@
394	383	static const u8 ppph[2] = { 0xff, 0x03 };
395	384	struct sock sk = (struct sock ) chan->private;
396	385	struct sock *sk_tun;
397		- int hdr_len;
398	386	struct l2tp_session *session;
399	387	struct l2tp_tunnel *tunnel;
400	388	struct pppol2tp_session *ps;
...	...	@@ -417,9 +405,6 @@
417	405	if (tunnel == NULL)
418	406	goto abort_put_sess;
419	407
420		- /* What header length is configured for this session? */
421		- hdr_len = pppol2tp_l2tp_header_len(session);
422		-
423	408	old_headroom = skb_headroom(skb);
424	409	if (skb_cow_head(skb, sizeof(ppph)))
425	410	goto abort_put_sess_tun;
...	...	@@ -432,7 +417,7 @@
432	417	skb->data[0] = ppph[0];
433	418	skb->data[1] = ppph[1];
434	419
435		- l2tp_xmit_skb(session, skb, hdr_len);
	420	+ l2tp_xmit_skb(session, skb, session->hdr_len);
436	421
437	422	sock_put(sk_tun);
438	423	sock_put(sk);
...	...	@@ -615,6 +600,7 @@
615	600	{
616	601	struct sock *sk = sock->sk;
617	602	struct sockaddr_pppol2tp sp = (struct sockaddr_pppol2tp ) uservaddr;
	603	+ struct sockaddr_pppol2tpv3 sp3 = (struct sockaddr_pppol2tpv3 ) uservaddr;
618	604	struct pppox_sock *po = pppox_sk(sk);
619	605	struct l2tp_session *session = NULL;
620	606	struct l2tp_tunnel *tunnel;
...	...	@@ -622,6 +608,10 @@
622	608	struct dst_entry *dst;
623	609	struct l2tp_session_cfg cfg = { 0, };
624	610	int error = 0;
	611	+ u32 tunnel_id, peer_tunnel_id;
	612	+ u32 session_id, peer_session_id;
	613	+ int ver = 2;
	614	+ int fd;
625	615
626	616	lock_sock(sk);
627	617
628	618
629	619
630	620
631	621
...	...	@@ -639,21 +629,40 @@
639	629	if (sk->sk_user_data)
640	630	goto end; /* socket is already attached */
641	631
642		- /* Don't bind if s_tunnel is 0 */
	632	+ /* Get params from socket address. Handle L2TPv2 and L2TPv3 */
	633	+ if (sockaddr_len == sizeof(struct sockaddr_pppol2tp)) {
	634	+ fd = sp->pppol2tp.fd;
	635	+ tunnel_id = sp->pppol2tp.s_tunnel;
	636	+ peer_tunnel_id = sp->pppol2tp.d_tunnel;
	637	+ session_id = sp->pppol2tp.s_session;
	638	+ peer_session_id = sp->pppol2tp.d_session;
	639	+ } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpv3)) {
	640	+ ver = 3;
	641	+ fd = sp3->pppol2tp.fd;
	642	+ tunnel_id = sp3->pppol2tp.s_tunnel;
	643	+ peer_tunnel_id = sp3->pppol2tp.d_tunnel;
	644	+ session_id = sp3->pppol2tp.s_session;
	645	+ peer_session_id = sp3->pppol2tp.d_session;
	646	+ } else {
	647	+ error = -EINVAL;
	648	+ goto end; /* bad socket address */
	649	+ }
	650	+
	651	+ /* Don't bind if tunnel_id is 0 */
643	652	error = -EINVAL;
644		- if (sp->pppol2tp.s_tunnel == 0)
	653	+ if (tunnel_id == 0)
645	654	goto end;
646	655
647		- /* Special case: create tunnel context if s_session and
648		- * d_session is 0. Otherwise look up tunnel using supplied
	656	+ /* Special case: create tunnel context if session_id and
	657	+ * peer_session_id is 0. Otherwise look up tunnel using supplied
649	658	* tunnel id.
650	659	*/
651		- if ((sp->pppol2tp.s_session == 0) && (sp->pppol2tp.d_session == 0)) {
652		- error = l2tp_tunnel_create(sock_net(sk), sp->pppol2tp.fd, 2, sp->pppol2tp.s_tunnel, sp->pppol2tp.d_tunnel, NULL, &tunnel);
	660	+ if ((session_id == 0) && (peer_session_id == 0)) {
	661	+ error = l2tp_tunnel_create(sock_net(sk), fd, ver, tunnel_id, peer_tunnel_id, NULL, &tunnel);
653	662	if (error < 0)
654	663	goto end;
655	664	} else {
656		- tunnel = l2tp_tunnel_find(sock_net(sk), sp->pppol2tp.s_tunnel);
	665	+ tunnel = l2tp_tunnel_find(sock_net(sk), tunnel_id);
657	666
658	667	/* Error if we can't find the tunnel */
659	668	error = -ENOENT;
660	669
661	670
...	...	@@ -670,20 +679,21 @@
670	679
671	680	/* Check that this session doesn't already exist */
672	681	error = -EEXIST;
673		- session = l2tp_session_find(sock_net(sk), tunnel, sp->pppol2tp.s_session);
	682	+ session = l2tp_session_find(sock_net(sk), tunnel, session_id);
674	683	if (session != NULL)
675	684	goto end;
676	685
677		- /* Default MTU must allow space for UDP/L2TP/PPP
678		- * headers.
679		- */
680		- cfg.mtu = cfg.mru = 1500 - PPPOL2TP_HEADER_OVERHEAD;
	686	+ /* Default MTU values. */
	687	+ if (cfg.mtu == 0)
	688	+ cfg.mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD;
	689	+ if (cfg.mru == 0)
	690	+ cfg.mru = cfg.mtu;
681	691	cfg.debug = tunnel->debug;
682	692
683	693	/* Allocate and initialize a new session context. */
684	694	session = l2tp_session_create(sizeof(struct pppol2tp_session),
685		- tunnel, sp->pppol2tp.s_session,
686		- sp->pppol2tp.d_session, &cfg);
	695	+ tunnel, session_id,
	696	+ peer_session_id, &cfg);
687	697	if (session == NULL) {
688	698	error = -ENOMEM;
689	699	goto end;
...	...	@@ -756,8 +766,7 @@
756	766	static int pppol2tp_getname(struct socket sock, struct sockaddr uaddr,
757	767	int *usockaddr_len, int peer)
758	768	{
759		- int len = sizeof(struct sockaddr_pppol2tp);
760		- struct sockaddr_pppol2tp sp;
	769	+ int len = 0;
761	770	int error = 0;
762	771	struct l2tp_session *session;
763	772	struct l2tp_tunnel *tunnel;
764	773
...	...	@@ -783,21 +792,40 @@
783	792	goto end_put_sess;
784	793	}
785	794
786		- memset(&sp, 0, len);
787		- sp.sa_family = AF_PPPOX;
788		- sp.sa_protocol = PX_PROTO_OL2TP;
789		- sp.pppol2tp.fd = tunnel->fd;
790		- sp.pppol2tp.pid = pls->owner;
791		- sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
792		- sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
793		- sp.pppol2tp.s_session = session->session_id;
794		- sp.pppol2tp.d_session = session->peer_session_id;
795	795	inet = inet_sk(sk);
796		- sp.pppol2tp.addr.sin_family = AF_INET;
797		- sp.pppol2tp.addr.sin_port = inet->inet_dport;
798		- sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
799		-
800		- memcpy(uaddr, &sp, len);
	796	+ if (tunnel->version == 2) {
	797	+ struct sockaddr_pppol2tp sp;
	798	+ len = sizeof(sp);
	799	+ memset(&sp, 0, len);
	800	+ sp.sa_family = AF_PPPOX;
	801	+ sp.sa_protocol = PX_PROTO_OL2TP;
	802	+ sp.pppol2tp.fd = tunnel->fd;
	803	+ sp.pppol2tp.pid = pls->owner;
	804	+ sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
	805	+ sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
	806	+ sp.pppol2tp.s_session = session->session_id;
	807	+ sp.pppol2tp.d_session = session->peer_session_id;
	808	+ sp.pppol2tp.addr.sin_family = AF_INET;
	809	+ sp.pppol2tp.addr.sin_port = inet->inet_dport;
	810	+ sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
	811	+ memcpy(uaddr, &sp, len);
	812	+ } else if (tunnel->version == 3) {
	813	+ struct sockaddr_pppol2tpv3 sp;
	814	+ len = sizeof(sp);
	815	+ memset(&sp, 0, len);
	816	+ sp.sa_family = AF_PPPOX;
	817	+ sp.sa_protocol = PX_PROTO_OL2TP;
	818	+ sp.pppol2tp.fd = tunnel->fd;
	819	+ sp.pppol2tp.pid = pls->owner;
	820	+ sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
	821	+ sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
	822	+ sp.pppol2tp.s_session = session->session_id;
	823	+ sp.pppol2tp.d_session = session->peer_session_id;
	824	+ sp.pppol2tp.addr.sin_family = AF_INET;
	825	+ sp.pppol2tp.addr.sin_port = inet->inet_dport;
	826	+ sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
	827	+ memcpy(uaddr, &sp, len);
	828	+ }
801	829
802	830	*usockaddr_len = len;
803	831