From 554ae6e792ef38020b80b4d5127c51d510c0918f Mon Sep 17 00:00:00 2001 From: David Ahern Date: Thu, 1 Dec 2016 08:48:08 -0800 Subject: samples/bpf: add userspace example for prohibiting sockets Add examples preventing a process in a cgroup from opening a socket based family, protocol and type. Signed-off-by: David Ahern Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller --- samples/bpf/sock_flags_kern.c | 44 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 samples/bpf/sock_flags_kern.c (limited to 'samples/bpf/sock_flags_kern.c') diff --git a/samples/bpf/sock_flags_kern.c b/samples/bpf/sock_flags_kern.c new file mode 100644 index 000000000000..533dd11a6baa --- /dev/null +++ b/samples/bpf/sock_flags_kern.c @@ -0,0 +1,44 @@ +#include +#include +#include +#include +#include +#include "bpf_helpers.h" + +SEC("cgroup/sock1") +int bpf_prog1(struct bpf_sock *sk) +{ + char fmt[] = "socket: family %d type %d protocol %d\n"; + + bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol); + + /* block PF_INET6, SOCK_RAW, IPPROTO_ICMPV6 sockets + * ie., make ping6 fail + */ + if (sk->family == PF_INET6 && + sk->type == SOCK_RAW && + sk->protocol == IPPROTO_ICMPV6) + return 0; + + return 1; +} + +SEC("cgroup/sock2") +int bpf_prog2(struct bpf_sock *sk) +{ + char fmt[] = "socket: family %d type %d protocol %d\n"; + + bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol); + + /* block PF_INET, SOCK_RAW, IPPROTO_ICMP sockets + * ie., make ping fail + */ + if (sk->family == PF_INET && + sk->type == SOCK_RAW && + sk->protocol == IPPROTO_ICMP) + return 0; + + return 1; +} + +char _license[] SEC("license") = "GPL"; -- cgit