wasm-bpf/examples/go-execve/main.go

61 lines
1.3 KiB
Go

package main
import (
"bytes"
_ "embed"
"fmt"
"go_wasm/helper"
"unsafe"
)
type CString struct {
s []byte
}
func (c CString) new(s string) *CString {
c.s = bytes.Join([][]byte{[]byte(s), {0}}, nil)
return &c
}
func (c *CString) toWasmPtr() int32 {
return int32(uintptr(unsafe.Pointer(&(c.s[0]))))
}
//go:embed execve.bpf.o
var obj []byte
//export go-callback
func callback(ctx, data, size uint32) uint32 {
// I'm not good at Go...
/*
#define COMM_SIZE 352
struct comm_event {
int pid;
char parent_proc[16];
char command[COMM_SIZE];
};
*/
ptr := (unsafe.Pointer(uintptr(data)))
pid := (unsafe.Slice((*int32)(ptr), 1))[0]
byte_arr := unsafe.Slice((*byte)(ptr), size)
parent_proc := string(byte_arr[4 : 4+16])
command := string(byte_arr[4+16 : 4+16+352])
fmt.Printf("[%d] %s -> %s\n", pid, parent_proc, command)
return 0
}
func main() {
var bpfObj int32 = int32(uintptr(unsafe.Pointer(&obj[0])))
objPtr := helper.WasmLoadBpfObject(bpfObj, int32(len(obj)))
helper.WasmAttachBpfProgram(objPtr, CString{}.new("sys_enter_execve").toWasmPtr(), 0)
mapFd := helper.WasmBpfMapFdByName(objPtr, CString{}.new("comm_event").toWasmPtr())
buf := make([]byte, 512, 512)
for {
helper.PerfBufferPoll(objPtr, mapFd, 0, int32(uintptr(unsafe.Pointer(&buf[0]))), int32(len(buf)), 100)
}
}