diff --git a/net/core/lwt_bpf.c b/net/core/lwt_bpf.c index e5a9850d9f4804bd928f7e75cc4e059809636d5b..079871fc020fc7da6786f46eb975f955e9fae5f1 100644 --- a/net/core/lwt_bpf.c +++ b/net/core/lwt_bpf.c @@ -16,6 +16,7 @@ #include #include #include +#include struct bpf_lwt_prog { struct bpf_prog *prog; @@ -390,10 +391,72 @@ static const struct lwtunnel_encap_ops bpf_encap_ops = { .owner = THIS_MODULE, }; +static int handle_gso_type(struct sk_buff *skb, unsigned int gso_type, + int encap_len) +{ + struct skb_shared_info *shinfo = skb_shinfo(skb); + + gso_type |= SKB_GSO_DODGY; + shinfo->gso_type |= gso_type; + skb_decrease_gso_size(shinfo, encap_len); + shinfo->gso_segs = 0; + return 0; +} + static int handle_gso_encap(struct sk_buff *skb, bool ipv4, int encap_len) { - /* Handling of GSO-enabled packets is added in the next patch. */ - return -EOPNOTSUPP; + int next_hdr_offset; + void *next_hdr; + __u8 protocol; + + /* SCTP and UDP_L4 gso need more nuanced handling than what + * handle_gso_type() does above: skb_decrease_gso_size() is not enough. + * So at the moment only TCP GSO packets are let through. + */ + if (!(skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) + return -ENOTSUPP; + + if (ipv4) { + protocol = ip_hdr(skb)->protocol; + next_hdr_offset = sizeof(struct iphdr); + next_hdr = skb_network_header(skb) + next_hdr_offset; + } else { + protocol = ipv6_hdr(skb)->nexthdr; + next_hdr_offset = sizeof(struct ipv6hdr); + next_hdr = skb_network_header(skb) + next_hdr_offset; + } + + switch (protocol) { + case IPPROTO_GRE: + next_hdr_offset += sizeof(struct gre_base_hdr); + if (next_hdr_offset > encap_len) + return -EINVAL; + + if (((struct gre_base_hdr *)next_hdr)->flags & GRE_CSUM) + return handle_gso_type(skb, SKB_GSO_GRE_CSUM, + encap_len); + return handle_gso_type(skb, SKB_GSO_GRE, encap_len); + + case IPPROTO_UDP: + next_hdr_offset += sizeof(struct udphdr); + if (next_hdr_offset > encap_len) + return -EINVAL; + + if (((struct udphdr *)next_hdr)->check) + return handle_gso_type(skb, SKB_GSO_UDP_TUNNEL_CSUM, + encap_len); + return handle_gso_type(skb, SKB_GSO_UDP_TUNNEL, encap_len); + + case IPPROTO_IP: + case IPPROTO_IPV6: + if (ipv4) + return handle_gso_type(skb, SKB_GSO_IPXIP4, encap_len); + else + return handle_gso_type(skb, SKB_GSO_IPXIP6, encap_len); + + default: + return -EPROTONOSUPPORT; + } } int bpf_lwt_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len, bool ingress)