54 lines
1.1 KiB
Go
54 lines
1.1 KiB
Go
package netlink
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import (
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"unsafe"
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"golang.org/x/sys/unix"
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)
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type BpfProgType uint32
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const (
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BPF_PROG_TYPE_UNSPEC BpfProgType = iota
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BPF_PROG_TYPE_SOCKET_FILTER
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BPF_PROG_TYPE_KPROBE
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BPF_PROG_TYPE_SCHED_CLS
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BPF_PROG_TYPE_SCHED_ACT
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BPF_PROG_TYPE_TRACEPOINT
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BPF_PROG_TYPE_XDP
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)
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type BPFAttr struct {
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ProgType uint32
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InsnCnt uint32
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Insns uintptr
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License uintptr
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LogLevel uint32
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LogSize uint32
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LogBuf uintptr
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KernVersion uint32
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}
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// loadSimpleBpf loads a trivial bpf program for testing purposes.
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func loadSimpleBpf(progType BpfProgType, ret uint32) (int, error) {
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insns := []uint64{
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0x00000000000000b7 | (uint64(ret) << 32),
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0x0000000000000095,
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}
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license := []byte{'A', 'S', 'L', '2', '\x00'}
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attr := BPFAttr{
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ProgType: uint32(progType),
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InsnCnt: uint32(len(insns)),
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Insns: uintptr(unsafe.Pointer(&insns[0])),
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License: uintptr(unsafe.Pointer(&license[0])),
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}
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fd, _, errno := unix.Syscall(unix.SYS_BPF,
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5, /* bpf cmd */
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uintptr(unsafe.Pointer(&attr)),
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unsafe.Sizeof(attr))
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if errno != 0 {
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return 0, errno
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}
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return int(fd), nil
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}
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