X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=drivers%2Fnet%2Fpppol2tp.c;h=f1a946785c6aee3bf580ad6015d9b825318c6566;hb=ce279e6ec91c49f2c5f59f7492e19d39edbf8bbd;hp=e98d9773158d287ba1ae35052dca968fc6cf5735;hpb=855caa37b9b61c1ccfeb91a2bc04d90bfc5e4525;p=linux-2.6-omap-h63xx.git diff --git a/drivers/net/pppol2tp.c b/drivers/net/pppol2tp.c index e98d9773158..f1a946785c6 100644 --- a/drivers/net/pppol2tp.c +++ b/drivers/net/pppol2tp.c @@ -489,6 +489,30 @@ out: spin_unlock_bh(&session->reorder_q.lock); } +static inline int pppol2tp_verify_udp_checksum(struct sock *sk, + struct sk_buff *skb) +{ + struct udphdr *uh = udp_hdr(skb); + u16 ulen = ntohs(uh->len); + struct inet_sock *inet; + __wsum psum; + + if (sk->sk_no_check || skb_csum_unnecessary(skb) || !uh->check) + return 0; + + inet = inet_sk(sk); + psum = csum_tcpudp_nofold(inet->saddr, inet->daddr, ulen, + IPPROTO_UDP, 0); + + if ((skb->ip_summed == CHECKSUM_COMPLETE) && + !csum_fold(csum_add(psum, skb->csum))) + return 0; + + skb->csum = psum; + + return __skb_checksum_complete(skb); +} + /* Internal receive frame. Do the real work of receiving an L2TP data frame * here. The skb is not on a list when we get here. * Returns 0 if the packet was a data packet and was successfully passed on. @@ -509,6 +533,9 @@ static int pppol2tp_recv_core(struct sock *sock, struct sk_buff *skb) if (tunnel == NULL) goto no_tunnel; + if (tunnel->sock && pppol2tp_verify_udp_checksum(tunnel->sock, skb)) + goto discard_bad_csum; + /* UDP always verifies the packet length. */ __skb_pull(skb, sizeof(struct udphdr)); @@ -725,6 +752,14 @@ discard: return 0; +discard_bad_csum: + LIMIT_NETDEBUG("%s: UDP: bad checksum\n", tunnel->name); + UDP_INC_STATS_USER(&init_net, UDP_MIB_INERRORS, 0); + tunnel->stats.rx_errors++; + kfree_skb(skb); + + return 0; + error: /* Put UDP header back */ __skb_push(skb, sizeof(struct udphdr)); @@ -851,7 +886,7 @@ static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msgh static const unsigned char ppph[2] = { 0xff, 0x03 }; struct sock *sk = sock->sk; struct inet_sock *inet; - __wsum csum = 0; + __wsum csum; struct sk_buff *skb; int error; int hdr_len; @@ -859,6 +894,8 @@ static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msgh struct pppol2tp_tunnel *tunnel; struct udphdr *uh; unsigned int len; + struct sock *sk_tun; + u16 udp_len; error = -ENOTCONN; if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) @@ -870,7 +907,8 @@ static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msgh if (session == NULL) goto error; - tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock); + sk_tun = session->tunnel_sock; + tunnel = pppol2tp_sock_to_tunnel(sk_tun); if (tunnel == NULL) goto error_put_sess; @@ -893,11 +931,12 @@ static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msgh skb_reset_transport_header(skb); /* Build UDP header */ - inet = inet_sk(session->tunnel_sock); + inet = inet_sk(sk_tun); + udp_len = hdr_len + sizeof(ppph) + total_len; uh = (struct udphdr *) skb->data; uh->source = inet->sport; uh->dest = inet->dport; - uh->len = htons(hdr_len + sizeof(ppph) + total_len); + uh->len = htons(udp_len); uh->check = 0; skb_put(skb, sizeof(struct udphdr)); @@ -919,8 +958,22 @@ static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msgh skb_put(skb, total_len); /* Calculate UDP checksum if configured to do so */ - if (session->tunnel_sock->sk_no_check != UDP_CSUM_NOXMIT) - csum = udp_csum_outgoing(sk, skb); + if (sk_tun->sk_no_check == UDP_CSUM_NOXMIT) + skb->ip_summed = CHECKSUM_NONE; + else if (!(skb->dst->dev->features & NETIF_F_V4_CSUM)) { + skb->ip_summed = CHECKSUM_COMPLETE; + csum = skb_checksum(skb, 0, udp_len, 0); + uh->check = csum_tcpudp_magic(inet->saddr, inet->daddr, + udp_len, IPPROTO_UDP, csum); + if (uh->check == 0) + uh->check = CSUM_MANGLED_0; + } else { + skb->ip_summed = CHECKSUM_PARTIAL; + skb->csum_start = skb_transport_header(skb) - skb->head; + skb->csum_offset = offsetof(struct udphdr, check); + uh->check = ~csum_tcpudp_magic(inet->saddr, inet->daddr, + udp_len, IPPROTO_UDP, 0); + } /* Debug */ if (session->send_seq) @@ -1008,13 +1061,14 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb) struct sock *sk = (struct sock *) chan->private; struct sock *sk_tun; int hdr_len; + u16 udp_len; struct pppol2tp_session *session; struct pppol2tp_tunnel *tunnel; int rc; int headroom; int data_len = skb->len; struct inet_sock *inet; - __wsum csum = 0; + __wsum csum; struct udphdr *uh; unsigned int len; int old_headroom; @@ -1060,6 +1114,8 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb) /* Setup L2TP header */ pppol2tp_build_l2tp_header(session, __skb_push(skb, hdr_len)); + udp_len = sizeof(struct udphdr) + hdr_len + sizeof(ppph) + data_len; + /* Setup UDP header */ inet = inet_sk(sk_tun); __skb_push(skb, sizeof(*uh)); @@ -1067,13 +1123,9 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb) uh = udp_hdr(skb); uh->source = inet->sport; uh->dest = inet->dport; - uh->len = htons(sizeof(struct udphdr) + hdr_len + sizeof(ppph) + data_len); + uh->len = htons(udp_len); uh->check = 0; - /* *BROKEN* Calculate UDP checksum if configured to do so */ - if (sk_tun->sk_no_check != UDP_CSUM_NOXMIT) - csum = udp_csum_outgoing(sk_tun, skb); - /* Debug */ if (session->send_seq) PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG, @@ -1108,6 +1160,24 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb) skb->dst = dst_clone(__sk_dst_get(sk_tun)); pppol2tp_skb_set_owner_w(skb, sk_tun); + /* Calculate UDP checksum if configured to do so */ + if (sk_tun->sk_no_check == UDP_CSUM_NOXMIT) + skb->ip_summed = CHECKSUM_NONE; + else if (!(skb->dst->dev->features & NETIF_F_V4_CSUM)) { + skb->ip_summed = CHECKSUM_COMPLETE; + csum = skb_checksum(skb, 0, udp_len, 0); + uh->check = csum_tcpudp_magic(inet->saddr, inet->daddr, + udp_len, IPPROTO_UDP, csum); + if (uh->check == 0) + uh->check = CSUM_MANGLED_0; + } else { + skb->ip_summed = CHECKSUM_PARTIAL; + skb->csum_start = skb_transport_header(skb) - skb->head; + skb->csum_offset = offsetof(struct udphdr, check); + uh->check = ~csum_tcpudp_magic(inet->saddr, inet->daddr, + udp_len, IPPROTO_UDP, 0); + } + /* Queue the packet to IP for output */ len = skb->len; rc = ip_queue_xmit(skb, 1);