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// SPDX-License-Identifier: GPL-2.0
#include <linux/ptrace.h>
#include <linux/bpf.h>
#include <netinet/in.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#if defined(__TARGET_ARCH_x86)
#define SYSCALL_WRAPPER 1
#define SYS_PREFIX "__x64_"
#elif defined(__TARGET_ARCH_s390)
#define SYSCALL_WRAPPER 1
#define SYS_PREFIX "__s390x_"
#elif defined(__TARGET_ARCH_arm64)
#define SYSCALL_WRAPPER 1
#define SYS_PREFIX "__arm64_"
#else
#define SYSCALL_WRAPPER 0
#define SYS_PREFIX ""
#endif
static struct sockaddr_in old;
SEC("kprobe/" SYS_PREFIX "sys_connect")
int BPF_KPROBE(handle_sys_connect)
{
#if SYSCALL_WRAPPER == 1
struct pt_regs *real_regs;
#endif
struct sockaddr_in new;
void *ptr;
#if SYSCALL_WRAPPER == 0
ptr = (void *)PT_REGS_PARM2(ctx);
#else
real_regs = (struct pt_regs *)PT_REGS_PARM1(ctx);
bpf_probe_read_kernel(&ptr, sizeof(ptr), &PT_REGS_PARM2(real_regs));
#endif
bpf_probe_read_user(&old, sizeof(old), ptr);
__builtin_memset(&new, 0xab, sizeof(new));
bpf_probe_write_user(ptr, &new, sizeof(new));
return 0;
}
char _license[] SEC("license") = "GPL";
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