62 lines
1.1 KiB
Go
62 lines
1.1 KiB
Go
//go:build unix && !disable_jit && !purego
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package randomx
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import (
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"golang.org/x/sys/unix"
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"runtime"
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"unsafe"
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)
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func (f ProgramFunc) Execute(v uintptr) {
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if f == nil {
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panic("program is nil")
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}
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var reservedStackHack [8 * 8]byte
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for i := range reservedStackHack {
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reservedStackHack[i] = uint8(i)
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}
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memoryPtr := &f
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fun := *(*func(v uintptr))(unsafe.Pointer(&memoryPtr))
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fun(v)
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for i := range reservedStackHack {
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reservedStackHack[i] = uint8(-i)
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}
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runtime.KeepAlive(reservedStackHack)
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}
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func (f ProgramFunc) Close() error {
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return unix.Munmap(f)
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}
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func mapProgram(program []byte) ProgramFunc {
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// Write only
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execFunc, err := unix.Mmap(-1, 0, len(program), unix.PROT_WRITE, unix.MAP_PRIVATE|unix.MAP_ANONYMOUS)
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if err != nil {
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panic(err)
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}
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// Introduce machine code into the memory region
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copy(execFunc, program)
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// uphold W^X
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// Read and Exec only
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err = unix.Mprotect(execFunc, unix.PROT_READ|unix.PROT_EXEC)
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if err != nil {
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defer func() {
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// unmap if we err
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err := unix.Munmap(execFunc)
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if err != nil {
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panic(err)
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}
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}()
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panic(err)
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}
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return execFunc
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}
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