/* * $OpenBSD: mdprologue.S,v 1.2 1998/03/26 19:46:42 niklas Exp $*/ /* * Copyright (c) 1993 Paul Kranenburg * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Paul Kranenburg. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ /* * i386 run-time link editor entry points. */ #include .text .globl _binder, _binder_entry /* * _rtl(int version, struct crt_ldso *crtp) */ _rtl: # crt0 calls us here pushl %ebp # Allocate stack frame movl %esp,%ebp pushl %ebx call 1f # PIC function prologue 1: popl %ebx addl $_GLOBAL_OFFSET_TABLE_+[.-1b],%ebx movl 12(%ebp),%eax # Extract data from interface structure movl (%eax),%eax # base address of ld.so (first field) # setup arguments for rtld() movl (%ebx),%ecx # 1st entry in GOT is our __DYNAMIC addl %eax,%ecx # add load address pushl %ecx # 3rd arg pushl 12(%ebp) # 2nd arg == &crt. pushl 8(%ebp) # 1st arg == version addl _rtld@GOT(%ebx),%eax # relocate address of function call %eax # _rtld(version, crtp, DYNAMIC) addl $12,%esp # pop arguments popl %ebx leave # remove stack frame ret # First call to a procedure generally comes through here for # binding. _binder_entry: pushl %ebp # setup a stack frame movl %esp,%ebp pusha # save all regs xorl %eax,%eax # clear movl 4(%ebp),%esi # return address in PLT movw (%esi),%ax # get hold of relocation number subl $6,%esi # make it point to the jmpslot pushl %eax # pushd arguments pushl %esi # call _binder@PLT # _binder(rpc, index) addl $8,%esp # pop arguments movl %eax,4(%ebp) # return value from _binder() == actual # address of function popa # restore regs leave # remove our stack frame ret