diff options
Diffstat (limited to 'net/ipv4/fou.c')
| -rw-r--r-- | net/ipv4/fou.c | 170 |
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) { |