diff options
| -rw-r--r-- | include/net/lwtunnel.h | 2 | ||||
| -rw-r--r-- | net/core/filter.c | 3 | ||||
| -rw-r--r-- | net/core/lwt_bpf.c | 65 |
3 files changed, 69 insertions, 1 deletions
diff --git a/include/net/lwtunnel.h b/include/net/lwtunnel.h index 33fd9ba7e0e5..671113bcb2cc 100644 --- a/include/net/lwtunnel.h +++ b/include/net/lwtunnel.h @@ -126,6 +126,8 @@ int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b); int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb); int lwtunnel_input(struct sk_buff *skb); int lwtunnel_xmit(struct sk_buff *skb); +int bpf_lwt_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len, + bool ingress); static inline void lwtunnel_set_redirect(struct dst_entry *dst) { diff --git a/net/core/filter.c b/net/core/filter.c index 12c88c21b6b8..a78deb2656e1 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -73,6 +73,7 @@ #include <linux/seg6_local.h> #include <net/seg6.h> #include <net/seg6_local.h> +#include <net/lwtunnel.h> /** * sk_filter_trim_cap - run a packet through a socket filter @@ -4819,7 +4820,7 @@ static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len static int bpf_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len, bool ingress) { - return -EINVAL; /* Implemented in the next patch. */ + return bpf_lwt_push_ip_encap(skb, hdr, len, ingress); } #endif diff --git a/net/core/lwt_bpf.c b/net/core/lwt_bpf.c index a648568c5e8f..e5a9850d9f48 100644 --- a/net/core/lwt_bpf.c +++ b/net/core/lwt_bpf.c @@ -390,6 +390,71 @@ static const struct lwtunnel_encap_ops bpf_encap_ops = { .owner = THIS_MODULE, }; +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 bpf_lwt_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len, bool ingress) +{ + struct iphdr *iph; + bool ipv4; + int err; + + if (unlikely(len < sizeof(struct iphdr) || len > LWT_BPF_MAX_HEADROOM)) + return -EINVAL; + + /* validate protocol and length */ + iph = (struct iphdr *)hdr; + if (iph->version == 4) { + ipv4 = true; + if (unlikely(len < iph->ihl * 4)) + return -EINVAL; + } else if (iph->version == 6) { + ipv4 = false; + if (unlikely(len < sizeof(struct ipv6hdr))) + return -EINVAL; + } else { + return -EINVAL; + } + + if (ingress) + err = skb_cow_head(skb, len + skb->mac_len); + else + err = skb_cow_head(skb, + len + LL_RESERVED_SPACE(skb_dst(skb)->dev)); + if (unlikely(err)) + return err; + + /* push the encap headers and fix pointers */ + skb_reset_inner_headers(skb); + skb->encapsulation = 1; + skb_push(skb, len); + if (ingress) + skb_postpush_rcsum(skb, iph, len); + skb_reset_network_header(skb); + memcpy(skb_network_header(skb), hdr, len); + bpf_compute_data_pointers(skb); + skb_clear_hash(skb); + + if (ipv4) { + skb->protocol = htons(ETH_P_IP); + iph = ip_hdr(skb); + + if (!iph->check) + iph->check = ip_fast_csum((unsigned char *)iph, + iph->ihl); + } else { + skb->protocol = htons(ETH_P_IPV6); + } + + if (skb_is_gso(skb)) + return handle_gso_encap(skb, ipv4, len); + + return 0; +} + static int __init bpf_lwt_init(void) { return lwtunnel_encap_add_ops(&bpf_encap_ops, LWTUNNEL_ENCAP_BPF); |