diff options
Diffstat (limited to '')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/test_btf_skc_cls_ingress.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_btf_skc_cls_ingress.c b/tools/testing/selftests/bpf/progs/test_btf_skc_cls_ingress.c new file mode 100644 index 000000000000..e2bea4da194b --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_btf_skc_cls_ingress.c @@ -0,0 +1,174 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ + +#include <string.h> +#include <errno.h> +#include <netinet/in.h> +#include <linux/stddef.h> +#include <linux/bpf.h> +#include <linux/ipv6.h> +#include <linux/tcp.h> +#include <linux/if_ether.h> +#include <linux/pkt_cls.h> + +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_endian.h> +#include "bpf_tcp_helpers.h" + +struct sockaddr_in6 srv_sa6 = {}; +__u16 listen_tp_sport = 0; +__u16 req_sk_sport = 0; +__u32 recv_cookie = 0; +__u32 gen_cookie = 0; +__u32 linum = 0; + +#define LOG() ({ if (!linum) linum = __LINE__; }) + +static void test_syncookie_helper(struct ipv6hdr *ip6h, struct tcphdr *th, + struct tcp_sock *tp, + struct __sk_buff *skb) +{ + if (th->syn) { + __s64 mss_cookie; + void *data_end; + + data_end = (void *)(long)(skb->data_end); + + if (th->doff * 4 != 40) { + LOG(); + return; + } + + if ((void *)th + 40 > data_end) { + LOG(); + return; + } + + mss_cookie = bpf_tcp_gen_syncookie(tp, ip6h, sizeof(*ip6h), + th, 40); + if (mss_cookie < 0) { + if (mss_cookie != -ENOENT) + LOG(); + } else { + gen_cookie = (__u32)mss_cookie; + } + } else if (gen_cookie) { + /* It was in cookie mode */ + int ret = bpf_tcp_check_syncookie(tp, ip6h, sizeof(*ip6h), + th, sizeof(*th)); + + if (ret < 0) { + if (ret != -ENOENT) + LOG(); + } else { + recv_cookie = bpf_ntohl(th->ack_seq) - 1; + } + } +} + +static int handle_ip6_tcp(struct ipv6hdr *ip6h, struct __sk_buff *skb) +{ + struct bpf_sock_tuple *tuple; + struct bpf_sock *bpf_skc; + unsigned int tuple_len; + struct tcphdr *th; + void *data_end; + + data_end = (void *)(long)(skb->data_end); + + th = (struct tcphdr *)(ip6h + 1); + if (th + 1 > data_end) + return TC_ACT_OK; + + /* Is it the testing traffic? */ + if (th->dest != srv_sa6.sin6_port) + return TC_ACT_OK; + + tuple_len = sizeof(tuple->ipv6); + tuple = (struct bpf_sock_tuple *)&ip6h->saddr; + if ((void *)tuple + tuple_len > data_end) { + LOG(); + return TC_ACT_OK; + } + + bpf_skc = bpf_skc_lookup_tcp(skb, tuple, tuple_len, + BPF_F_CURRENT_NETNS, 0); + if (!bpf_skc) { + LOG(); + return TC_ACT_OK; + } + + if (bpf_skc->state == BPF_TCP_NEW_SYN_RECV) { + struct request_sock *req_sk; + + req_sk = (struct request_sock *)bpf_skc_to_tcp_request_sock(bpf_skc); + if (!req_sk) { + LOG(); + goto release; + } + + if (bpf_sk_assign(skb, req_sk, 0)) { + LOG(); + goto release; + } + + req_sk_sport = req_sk->__req_common.skc_num; + + bpf_sk_release(req_sk); + return TC_ACT_OK; + } else if (bpf_skc->state == BPF_TCP_LISTEN) { + struct tcp_sock *tp; + + tp = bpf_skc_to_tcp_sock(bpf_skc); + if (!tp) { + LOG(); + goto release; + } + + if (bpf_sk_assign(skb, tp, 0)) { + LOG(); + goto release; + } + + listen_tp_sport = tp->inet_conn.icsk_inet.sk.__sk_common.skc_num; + + test_syncookie_helper(ip6h, th, tp, skb); + bpf_sk_release(tp); + return TC_ACT_OK; + } + + if (bpf_sk_assign(skb, bpf_skc, 0)) + LOG(); + +release: + bpf_sk_release(bpf_skc); + return TC_ACT_OK; +} + +SEC("tc") +int cls_ingress(struct __sk_buff *skb) +{ + struct ipv6hdr *ip6h; + struct ethhdr *eth; + void *data_end; + + data_end = (void *)(long)(skb->data_end); + + eth = (struct ethhdr *)(long)(skb->data); + if (eth + 1 > data_end) + return TC_ACT_OK; + + if (eth->h_proto != bpf_htons(ETH_P_IPV6)) + return TC_ACT_OK; + + ip6h = (struct ipv6hdr *)(eth + 1); + if (ip6h + 1 > data_end) + return TC_ACT_OK; + + if (ip6h->nexthdr == IPPROTO_TCP) + return handle_ip6_tcp(ip6h, skb); + + return TC_ACT_OK; +} + +char _license[] SEC("license") = "GPL"; |