cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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connect_force_port6.c (2343B)

      1// SPDX-License-Identifier: GPL-2.0
      2#include <string.h>
      3
      4#include <linux/bpf.h>
      5#include <linux/in.h>
      6#include <linux/in6.h>
      7#include <sys/socket.h>
      8
      9#include <bpf/bpf_helpers.h>
     10#include <bpf/bpf_endian.h>
     11
     12#include <bpf_sockopt_helpers.h>
     13
     14char _license[] SEC("license") = "GPL";
     15
     16struct svc_addr {
     17	__be32 addr[4];
     18	__be16 port;
     19};
     20
     21struct {
     22	__uint(type, BPF_MAP_TYPE_SK_STORAGE);
     23	__uint(map_flags, BPF_F_NO_PREALLOC);
     24	__type(key, int);
     25	__type(value, struct svc_addr);
     26} service_mapping SEC(".maps");
     27
     28SEC("cgroup/connect6")
     29int connect6(struct bpf_sock_addr *ctx)
     30{
     31	struct sockaddr_in6 sa = {};
     32	struct svc_addr *orig;
     33
     34	/* Force local address to [::1]:22223. */
     35	sa.sin6_family = AF_INET6;
     36	sa.sin6_port = bpf_htons(22223);
     37	sa.sin6_addr.s6_addr32[3] = bpf_htonl(1);
     38
     39	if (bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa)) != 0)
     40		return 0;
     41
     42	/* Rewire service [fc00::1]:60000 to backend [::1]:60124. */
     43	if (ctx->user_port == bpf_htons(60000)) {
     44		orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0,
     45					  BPF_SK_STORAGE_GET_F_CREATE);
     46		if (!orig)
     47			return 0;
     48
     49		orig->addr[0] = ctx->user_ip6[0];
     50		orig->addr[1] = ctx->user_ip6[1];
     51		orig->addr[2] = ctx->user_ip6[2];
     52		orig->addr[3] = ctx->user_ip6[3];
     53		orig->port = ctx->user_port;
     54
     55		ctx->user_ip6[0] = 0;
     56		ctx->user_ip6[1] = 0;
     57		ctx->user_ip6[2] = 0;
     58		ctx->user_ip6[3] = bpf_htonl(1);
     59		ctx->user_port = bpf_htons(60124);
     60	}
     61	return 1;
     62}
     63
     64SEC("cgroup/getsockname6")
     65int getsockname6(struct bpf_sock_addr *ctx)
     66{
     67	if (!get_set_sk_priority(ctx))
     68		return 1;
     69
     70	/* Expose local server as [fc00::1]:60000 to client. */
     71	if (ctx->user_port == bpf_htons(60124)) {
     72		ctx->user_ip6[0] = bpf_htonl(0xfc000000);
     73		ctx->user_ip6[1] = 0;
     74		ctx->user_ip6[2] = 0;
     75		ctx->user_ip6[3] = bpf_htonl(1);
     76		ctx->user_port = bpf_htons(60000);
     77	}
     78	return 1;
     79}
     80
     81SEC("cgroup/getpeername6")
     82int getpeername6(struct bpf_sock_addr *ctx)
     83{
     84	struct svc_addr *orig;
     85
     86	if (!get_set_sk_priority(ctx))
     87		return 1;
     88
     89	/* Expose service [fc00::1]:60000 as peer instead of backend. */
     90	if (ctx->user_port == bpf_htons(60124)) {
     91		orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0, 0);
     92		if (orig) {
     93			ctx->user_ip6[0] = orig->addr[0];
     94			ctx->user_ip6[1] = orig->addr[1];
     95			ctx->user_ip6[2] = orig->addr[2];
     96			ctx->user_ip6[3] = orig->addr[3];
     97			ctx->user_port = orig->port;
     98		}
     99	}
    100	return 1;
    101}