2018-02-01 01:26:34 +00:00
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/*
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2020-03-29 15:04:03 +00:00
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* Copyright (c) 2018, 2020 Ariadne Conill <ariadne@dereferenced.org>
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2018-02-01 01:26:34 +00:00
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*
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* Permission to use, copy, modify, and/or distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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*
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* This software is provided 'as is' and without any warranty, express or
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* implied. In no event shall the authors be liable for any damages arising
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* from the use of this software.
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*/
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2020-03-29 15:04:03 +00:00
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#include "defs.h"
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2020-12-06 08:59:59 +00:00
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FUNC(libucontext_trampoline)
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2018-02-01 01:26:34 +00:00
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/* get the proper context into position and test for NULL */
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leal (%esp,%ebx,4), %esp
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cmpl $0, (%esp)
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2018-02-15 04:32:16 +00:00
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2020-12-06 09:03:07 +00:00
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/* restore global offset table, exit@plt and libucontext_setcontext@plt need this */
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2018-02-15 04:32:16 +00:00
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call __i686.get_pc_thunk.bx
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addl $_GLOBAL_OFFSET_TABLE_, %ebx
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/* if we have no linked context, lets get out of here */
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je no_linked_context
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2018-02-01 01:26:34 +00:00
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/* call setcontext to switch to the linked context */
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2020-12-06 09:03:07 +00:00
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call libucontext_setcontext@plt
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2018-02-01 01:26:34 +00:00
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movl %eax, (%esp)
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2018-02-15 04:32:16 +00:00
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no_linked_context:
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2018-02-01 01:26:34 +00:00
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/* we are returning into a null context, it seems, so maybe we should exit */
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call exit@plt
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/* something is really hosed, call hlt to force termination */
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hlt
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2018-02-15 04:32:16 +00:00
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__i686.get_pc_thunk.bx:
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mov (%esp), %ebx
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ret
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2020-12-06 08:59:59 +00:00
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END(libucontext_trampoline)
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