Exemplo n.º 1
0
func StackInit(u models.Usercorn, args, env []string, auxv []byte) error {
	// push argv and envp strings
	envp, err := pushStrings(u, env...)
	if err != nil {
		return err
	}
	argv, err := pushStrings(u, args...)
	if err != nil {
		return err
	}
	// align stack pointer
	sp, _ := u.RegRead(u.Arch().SP)
	u.RegWrite(u.Arch().SP, (sp & ^uint64(15)))
	// end marker
	if _, err := u.Push(0); err != nil {
		return err
	}
	// auxv
	if len(auxv) > 0 {
		if _, err := u.PushBytes(auxv); err != nil {
			return err
		}
	}
	// envp
	if err := pushAddrs(u, envp); err != nil {
		return err
	}
	// argv
	if err := pushAddrs(u, argv); err != nil {
		return err
	}
	// argc
	_, err = u.Push(uint64(len(args)))
	return err
}
Exemplo n.º 2
0
func StackArgs(u models.Usercorn) func(n int) ([]uint64, error) {
	return func(n int) ([]uint64, error) {
		sp, _ := u.RegRead(u.Arch().SP)
		// starts with an empty slot
		s := u.StrucAt(sp + uint64(u.Bits()/8))

		ret := make([]uint64, n)
		for i := 0; i < n; i++ {
			var arg uint64
			var err error
			// TODO: simplify this when struc issue #47 is fixed
			if u.Bits() == 64 {
				err = s.Unpack(&arg)
			} else {
				var arg32 uint32
				err = s.Unpack(&arg32)
				arg = uint64(arg32)
			}
			if err != nil {
				return nil, err
			}
			ret[i] = arg
		}
		return ret, nil
	}
}
Exemplo n.º 3
0
func StackInit(u models.Usercorn, args, env []string, auxv []byte) error {
	if _, err := u.Push(0); err != nil {
		return err
	}
	if len(args) > 0 {
		if _, err := u.PushBytes([]byte(args[0] + "\x00")); err != nil {
			return err
		}
	}
	// push argv and envp strings
	envp, err := pushStrings(u, env...)
	if err != nil {
		return err
	}
	argv, err := pushStrings(u, args...)
	if err != nil {
		return err
	}
	// precalc envp -> argc for stack alignment
	envpb, err := packAddrs(u, envp)
	if err != nil {
		return err
	}
	argvb, err := packAddrs(u, argv)
	if err != nil {
		return err
	}
	var tmp [8]byte
	argcb, err := u.PackAddr(tmp[:], uint64(len(argv)))
	init := append(argcb, argvb...)
	init = append(init, envpb...)
	// align stack pointer
	sp, _ := u.RegRead(u.Arch().SP)
	sp &= ^uint64(15)
	off := len(init) & 15
	if off > 0 {
		sp -= uint64(16 - off)
	}
	u.RegWrite(u.Arch().SP, sp)
	// auxv
	if len(auxv) > 0 {
		if _, err := u.PushBytes(auxv); err != nil {
			return err
		}
	}
	// write envp -> argc
	u.PushBytes(init)
	return err
}