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Diffstat (limited to 'net/ipv4/fou.c')
-rw-r--r--net/ipv4/fou.c170
1 files changed, 161 insertions, 9 deletions
diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
index fb0db99adf9e..740ae099a0d9 100644
--- a/net/ipv4/fou.c
+++ b/net/ipv4/fou.c
@@ -63,6 +63,59 @@ static int fou_udp_recv(struct sock *sk, struct sk_buff *skb)
return -fou->protocol;
}
+static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr,
+ void *data, int hdrlen, u8 ipproto)
+{
+ __be16 *pd = data;
+ u16 start = ntohs(pd[0]);
+ u16 offset = ntohs(pd[1]);
+ u16 poffset = 0;
+ u16 plen;
+ __wsum csum, delta;
+ __sum16 *psum;
+
+ if (skb->remcsum_offload) {
+ /* Already processed in GRO path */
+ skb->remcsum_offload = 0;
+ return guehdr;
+ }
+
+ if (start > skb->len - hdrlen ||
+ offset > skb->len - hdrlen - sizeof(u16))
+ return NULL;
+
+ if (unlikely(skb->ip_summed != CHECKSUM_COMPLETE))
+ __skb_checksum_complete(skb);
+
+ plen = hdrlen + offset + sizeof(u16);
+ if (!pskb_may_pull(skb, plen))
+ return NULL;
+ guehdr = (struct guehdr *)&udp_hdr(skb)[1];
+
+ if (ipproto == IPPROTO_IP && sizeof(struct iphdr) < plen) {
+ struct iphdr *ip = (struct iphdr *)(skb->data + hdrlen);
+
+ /* If next header happens to be IP we can skip that for the
+ * checksum calculation since the IP header checksum is zero
+ * if correct.
+ */
+ poffset = ip->ihl * 4;
+ }
+
+ csum = csum_sub(skb->csum, skb_checksum(skb, poffset + hdrlen,
+ start - poffset - hdrlen, 0));
+
+ /* Set derived checksum in packet */
+ psum = (__sum16 *)(skb->data + hdrlen + offset);
+ delta = csum_sub(csum_fold(csum), *psum);
+ *psum = csum_fold(csum);
+
+ /* Adjust skb->csum since we changed the packet */
+ skb->csum = csum_add(skb->csum, delta);
+
+ return guehdr;
+}
+
static int gue_control_message(struct sk_buff *skb, struct guehdr *guehdr)
{
/* No support yet */
@@ -76,6 +129,7 @@ static int gue_udp_recv(struct sock *sk, struct sk_buff *skb)
size_t len, optlen, hdrlen;
struct guehdr *guehdr;
void *data;
+ u16 doffset = 0;
if (!fou)
return 1;
@@ -100,20 +154,43 @@ static int gue_udp_recv(struct sock *sk, struct sk_buff *skb)
if (guehdr->version != 0 || validate_gue_flags(guehdr, optlen))
goto drop;
- /* Pull UDP and GUE headers */
- fou_recv_pull(skb, len);
+ hdrlen = sizeof(struct guehdr) + optlen;
+
+ ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(skb)->tot_len) - len);
+
+ /* Pull UDP header now, skb->data points to guehdr */
+ __skb_pull(skb, sizeof(struct udphdr));
+
+ /* Pull csum through the guehdr now . This can be used if
+ * there is a remote checksum offload.
+ */
+ skb_postpull_rcsum(skb, udp_hdr(skb), len);
data = &guehdr[1];
if (guehdr->flags & GUE_FLAG_PRIV) {
- data += GUE_LEN_PRIV;
+ __be32 flags = *(__be32 *)(data + doffset);
+
+ doffset += GUE_LEN_PRIV;
- /* Process private flags */
+ if (flags & GUE_PFLAG_REMCSUM) {
+ guehdr = gue_remcsum(skb, guehdr, data + doffset,
+ hdrlen, guehdr->proto_ctype);
+ if (!guehdr)
+ goto drop;
+
+ data = &guehdr[1];
+
+ doffset += GUE_PLEN_REMCSUM;
+ }
}
if (unlikely(guehdr->control))
return gue_control_message(skb, guehdr);
+ __skb_pull(skb, hdrlen);
+ skb_reset_transport_header(skb);
+
return -guehdr->proto_ctype;
drop:
@@ -164,6 +241,66 @@ out_unlock:
return err;
}
+static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off,
+ struct guehdr *guehdr, void *data,
+ size_t hdrlen, u8 ipproto)
+{
+ __be16 *pd = data;
+ u16 start = ntohs(pd[0]);
+ u16 offset = ntohs(pd[1]);
+ u16 poffset = 0;
+ u16 plen;
+ void *ptr;
+ __wsum csum, delta;
+ __sum16 *psum;
+
+ if (skb->remcsum_offload)
+ return guehdr;
+
+ if (start > skb_gro_len(skb) - hdrlen ||
+ offset > skb_gro_len(skb) - hdrlen - sizeof(u16) ||
+ !NAPI_GRO_CB(skb)->csum_valid || skb->remcsum_offload)
+ return NULL;
+
+ plen = hdrlen + offset + sizeof(u16);
+
+ /* Pull checksum that will be written */
+ if (skb_gro_header_hard(skb, off + plen)) {
+ guehdr = skb_gro_header_slow(skb, off + plen, off);
+ if (!guehdr)
+ return NULL;
+ }
+
+ ptr = (void *)guehdr + hdrlen;
+
+ if (ipproto == IPPROTO_IP &&
+ (hdrlen + sizeof(struct iphdr) < plen)) {
+ struct iphdr *ip = (struct iphdr *)(ptr + hdrlen);
+
+ /* If next header happens to be IP we can skip
+ * that for the checksum calculation since the
+ * IP header checksum is zero if correct.
+ */
+ poffset = ip->ihl * 4;
+ }
+
+ csum = csum_sub(NAPI_GRO_CB(skb)->csum,
+ csum_partial(ptr + poffset, start - poffset, 0));
+
+ /* Set derived checksum in packet */
+ psum = (__sum16 *)(ptr + offset);
+ delta = csum_sub(csum_fold(csum), *psum);
+ *psum = csum_fold(csum);
+
+ /* Adjust skb->csum since we changed the packet */
+ skb->csum = csum_add(skb->csum, delta);
+ NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta);
+
+ skb->remcsum_offload = 1;
+
+ return guehdr;
+}
+
static struct sk_buff **gue_gro_receive(struct sk_buff **head,
struct sk_buff *skb)
{
@@ -174,6 +311,7 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
struct guehdr *guehdr;
size_t len, optlen, hdrlen, off;
void *data;
+ u16 doffset = 0;
int flush = 1;
off = skb_gro_offset(skb);
@@ -201,19 +339,33 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
hdrlen = sizeof(*guehdr) + optlen;
- skb_gro_pull(skb, hdrlen);
-
- /* Adjusted NAPI_GRO_CB(skb)->csum after skb_gro_pull()*/
+ /* Adjust NAPI_GRO_CB(skb)->csum to account for guehdr,
+ * this is needed if there is a remote checkcsum offload.
+ */
skb_gro_postpull_rcsum(skb, guehdr, hdrlen);
data = &guehdr[1];
if (guehdr->flags & GUE_FLAG_PRIV) {
- data += GUE_LEN_PRIV;
+ __be32 flags = *(__be32 *)(data + doffset);
- /* Process private flags */
+ doffset += GUE_LEN_PRIV;
+
+ if (flags & GUE_PFLAG_REMCSUM) {
+ guehdr = gue_gro_remcsum(skb, off, guehdr,
+ data + doffset, hdrlen,
+ guehdr->proto_ctype);
+ if (!guehdr)
+ goto out;
+
+ data = &guehdr[1];
+
+ doffset += GUE_PLEN_REMCSUM;
+ }
}
+ skb_gro_pull(skb, hdrlen);
+
flush = 0;
for (p = *head; p; p = p->next) {