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Diffstat (limited to 'net/ipv6/udp.c')
-rw-r--r--net/ipv6/udp.c141
1 files changed, 140 insertions, 1 deletions
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 33b59bd92c4..d79fa672445 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -638,6 +638,47 @@ static void udp_v6_flush_pending_frames(struct sock *sk)
}
}
+/**
+ * udp6_hwcsum_outgoing - handle outgoing HW checksumming
+ * @sk: socket we are sending on
+ * @skb: sk_buff containing the filled-in UDP header
+ * (checksum field must be zeroed out)
+ */
+static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
+ const struct in6_addr *saddr,
+ const struct in6_addr *daddr, int len)
+{
+ unsigned int offset;
+ struct udphdr *uh = udp_hdr(skb);
+ __wsum csum = 0;
+
+ if (skb_queue_len(&sk->sk_write_queue) == 1) {
+ /* Only one fragment on the socket. */
+ skb->csum_start = skb_transport_header(skb) - skb->head;
+ skb->csum_offset = offsetof(struct udphdr, check);
+ uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
+ } else {
+ /*
+ * HW-checksum won't work as there are two or more
+ * fragments on the socket so that all csums of sk_buffs
+ * should be together
+ */
+ offset = skb_transport_offset(skb);
+ skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
+
+ skb->ip_summed = CHECKSUM_NONE;
+
+ skb_queue_walk(&sk->sk_write_queue, skb) {
+ csum = csum_add(csum, skb->csum);
+ }
+
+ uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
+ csum);
+ if (uh->check == 0)
+ uh->check = CSUM_MANGLED_0;
+ }
+}
+
/*
* Sending
*/
@@ -668,7 +709,11 @@ static int udp_v6_push_pending_frames(struct sock *sk)
if (is_udplite)
csum = udplite_csum_outgoing(sk, skb);
- else
+ else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
+ udp6_hwcsum_outgoing(sk, skb, &fl->fl6_src, &fl->fl6_dst,
+ up->len);
+ goto send;
+ } else
csum = udp_csum_outgoing(sk, skb);
/* add protocol-dependent pseudo-header */
@@ -677,6 +722,7 @@ static int udp_v6_push_pending_frames(struct sock *sk)
if (uh->check == 0)
uh->check = CSUM_MANGLED_0;
+send:
err = ip6_push_pending_frames(sk);
out:
up->len = 0;
@@ -1032,9 +1078,102 @@ int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
}
#endif
+static int udp6_ufo_send_check(struct sk_buff *skb)
+{
+ struct ipv6hdr *ipv6h;
+ struct udphdr *uh;
+
+ if (!pskb_may_pull(skb, sizeof(*uh)))
+ return -EINVAL;
+
+ ipv6h = ipv6_hdr(skb);
+ uh = udp_hdr(skb);
+
+ uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
+ IPPROTO_UDP, 0);
+ skb->csum_start = skb_transport_header(skb) - skb->head;
+ skb->csum_offset = offsetof(struct udphdr, check);
+ skb->ip_summed = CHECKSUM_PARTIAL;
+ return 0;
+}
+
+static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, int features)
+{
+ struct sk_buff *segs = ERR_PTR(-EINVAL);
+ unsigned int mss;
+ unsigned int unfrag_ip6hlen, unfrag_len;
+ struct frag_hdr *fptr;
+ u8 *mac_start, *prevhdr;
+ u8 nexthdr;
+ u8 frag_hdr_sz = sizeof(struct frag_hdr);
+ int offset;
+ __wsum csum;
+
+ mss = skb_shinfo(skb)->gso_size;
+ if (unlikely(skb->len <= mss))
+ goto out;
+
+ if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
+ /* Packet is from an untrusted source, reset gso_segs. */
+ int type = skb_shinfo(skb)->gso_type;
+
+ if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
+ !(type & (SKB_GSO_UDP))))
+ goto out;
+
+ skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
+
+ segs = NULL;
+ goto out;
+ }
+
+ /* Do software UFO. Complete and fill in the UDP checksum as HW cannot
+ * do checksum of UDP packets sent as multiple IP fragments.
+ */
+ offset = skb->csum_start - skb_headroom(skb);
+ csum = skb_checksum(skb, offset, skb->len- offset, 0);
+ offset += skb->csum_offset;
+ *(__sum16 *)(skb->data + offset) = csum_fold(csum);
+ skb->ip_summed = CHECKSUM_NONE;
+
+ /* Check if there is enough headroom to insert fragment header. */
+ if ((skb_headroom(skb) < frag_hdr_sz) &&
+ pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
+ goto out;
+
+ /* Find the unfragmentable header and shift it left by frag_hdr_sz
+ * bytes to insert fragment header.
+ */
+ unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
+ nexthdr = *prevhdr;
+ *prevhdr = NEXTHDR_FRAGMENT;
+ unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
+ unfrag_ip6hlen;
+ mac_start = skb_mac_header(skb);
+ memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
+
+ skb->mac_header -= frag_hdr_sz;
+ skb->network_header -= frag_hdr_sz;
+
+ fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
+ fptr->nexthdr = nexthdr;
+ fptr->reserved = 0;
+ ipv6_select_ident(fptr);
+
+ /* Fragment the skb. ipv6 header and the remaining fields of the
+ * fragment header are updated in ipv6_gso_segment()
+ */
+ segs = skb_segment(skb, features);
+
+out:
+ return segs;
+}
+
static struct inet6_protocol udpv6_protocol = {
.handler = udpv6_rcv,
.err_handler = udpv6_err,
+ .gso_send_check = udp6_ufo_send_check,
+ .gso_segment = udp6_ufo_fragment,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};