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// SPDX-License-Identifier: GPL-2.0
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include <bpf/bpf_core_read.h>
#include "bpf_misc.h"
static struct sockaddr_in old;
static int handle_sys_connect_common(struct sockaddr_in *uservaddr)
{
struct sockaddr_in new;
bpf_probe_read_user(&old, sizeof(old), uservaddr);
__builtin_memset(&new, 0xab, sizeof(new));
bpf_probe_write_user(uservaddr, &new, sizeof(new));
return 0;
}
SEC("ksyscall/connect")
int BPF_KSYSCALL(handle_sys_connect, int fd, struct sockaddr_in *uservaddr,
int addrlen)
{
return handle_sys_connect_common(uservaddr);
}
#if defined(bpf_target_s390)
#ifndef SYS_CONNECT
#define SYS_CONNECT 3
#endif
SEC("ksyscall/socketcall")
int BPF_KSYSCALL(handle_sys_socketcall, int call, unsigned long *args)
{
if (call == SYS_CONNECT) {
struct sockaddr_in *uservaddr;
bpf_probe_read_user(&uservaddr, sizeof(uservaddr), &args[1]);
return handle_sys_connect_common(uservaddr);
}
return 0;
}
#endif
char _license[] SEC("license") = "GPL";
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