diff options
Diffstat (limited to 'net/l2tp/l2tp_ppp.c')
| -rw-r--r-- | net/l2tp/l2tp_ppp.c | 33 |
1 files changed, 11 insertions, 22 deletions
diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c index 9ac02c93df98..000c9829304c 100644 --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -183,25 +183,6 @@ out: * Receive data handling *****************************************************************************/ -static int pppol2tp_recv_payload_hook(struct sk_buff *skb) -{ - /* Skip PPP header, if present. In testing, Microsoft L2TP clients - * don't send the PPP header (PPP header compression enabled), but - * other clients can include the header. So we cope with both cases - * here. The PPP header is always FF03 when using L2TP. - * - * Note that skb->data[] isn't dereferenced from a u16 ptr here since - * the field may be unaligned. - */ - if (!pskb_may_pull(skb, 2)) - return 1; - - if ((skb->data[0] == PPP_ALLSTATIONS) && (skb->data[1] == PPP_UI)) - skb_pull(skb, 2); - - return 0; -} - /* Receive message. This is the recvmsg for the PPPoL2TP socket. */ static int pppol2tp_recvmsg(struct socket *sock, struct msghdr *msg, @@ -248,6 +229,17 @@ static void pppol2tp_recv(struct l2tp_session *session, struct sk_buff *skb, int if (sk == NULL) goto no_sock; + /* If the first two bytes are 0xFF03, consider that it is the PPP's + * Address and Control fields and skip them. The L2TP module has always + * worked this way, although, in theory, the use of these fields should + * be negociated and handled at the PPP layer. These fields are + * constant: 0xFF is the All-Stations Address and 0x03 the Unnumbered + * Information command with Poll/Final bit set to zero (RFC 1662). + */ + if (pskb_may_pull(skb, 2) && skb->data[0] == PPP_ALLSTATIONS && + skb->data[1] == PPP_UI) + skb_pull(skb, 2); + if (sk->sk_state & PPPOX_BOUND) { struct pppox_sock *po; @@ -763,9 +755,6 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr, goto end; } - if (tunnel->recv_payload_hook == NULL) - tunnel->recv_payload_hook = pppol2tp_recv_payload_hook; - if (tunnel->peer_tunnel_id == 0) tunnel->peer_tunnel_id = info.peer_tunnel_id; |