cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

socket_cookie_prog.c (2121B)

      1// SPDX-License-Identifier: GPL-2.0
      2// Copyright (c) 2018 Facebook
      3
      4#include "vmlinux.h"
      5
      6#include <bpf/bpf_helpers.h>
      7#include <bpf/bpf_endian.h>
      8#include <bpf/bpf_tracing.h>
      9
     10#define AF_INET6 10
     11
     12struct socket_cookie {
     13	__u64 cookie_key;
     14	__u32 cookie_value;
     15};
     16
     17struct {
     18	__uint(type, BPF_MAP_TYPE_SK_STORAGE);
     19	__uint(map_flags, BPF_F_NO_PREALLOC);
     20	__type(key, int);
     21	__type(value, struct socket_cookie);
     22} socket_cookies SEC(".maps");
     23
     24/*
     25 * These three programs get executed in a row on connect() syscalls. The
     26 * userspace side of the test creates a client socket, issues a connect() on it
     27 * and then checks that the local storage associated with this socket has:
     28 * cookie_value == local_port << 8 | 0xFF
     29 * The different parts of this cookie_value are appended by those hooks if they
     30 * all agree on the output of bpf_get_socket_cookie().
     31 */
     32SEC("cgroup/connect6")
     33int set_cookie(struct bpf_sock_addr *ctx)
     34{
     35	struct socket_cookie *p;
     36
     37	if (ctx->family != AF_INET6 || ctx->user_family != AF_INET6)
     38		return 1;
     39
     40	p = bpf_sk_storage_get(&socket_cookies, ctx->sk, 0,
     41			       BPF_SK_STORAGE_GET_F_CREATE);
     42	if (!p)
     43		return 1;
     44
     45	p->cookie_value = 0xF;
     46	p->cookie_key = bpf_get_socket_cookie(ctx);
     47
     48	return 1;
     49}
     50
     51SEC("sockops")
     52int update_cookie_sockops(struct bpf_sock_ops *ctx)
     53{
     54	struct bpf_sock *sk = ctx->sk;
     55	struct socket_cookie *p;
     56
     57	if (ctx->family != AF_INET6)
     58		return 1;
     59
     60	if (ctx->op != BPF_SOCK_OPS_TCP_CONNECT_CB)
     61		return 1;
     62
     63	if (!sk)
     64		return 1;
     65
     66	p = bpf_sk_storage_get(&socket_cookies, sk, 0, 0);
     67	if (!p)
     68		return 1;
     69
     70	if (p->cookie_key != bpf_get_socket_cookie(ctx))
     71		return 1;
     72
     73	p->cookie_value |= (ctx->local_port << 8);
     74
     75	return 1;
     76}
     77
     78SEC("fexit/inet_stream_connect")
     79int BPF_PROG(update_cookie_tracing, struct socket *sock,
     80	     struct sockaddr *uaddr, int addr_len, int flags)
     81{
     82	struct socket_cookie *p;
     83
     84	if (uaddr->sa_family != AF_INET6)
     85		return 0;
     86
     87	p = bpf_sk_storage_get(&socket_cookies, sock->sk, 0, 0);
     88	if (!p)
     89		return 0;
     90
     91	if (p->cookie_key != bpf_get_socket_cookie(sock->sk))
     92		return 0;
     93
     94	p->cookie_value |= 0xF0;
     95
     96	return 0;
     97}
     98
     99char _license[] SEC("license") = "GPL";