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/*
* 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 withough 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.
*
* $Id: mdprologue.S,v 1.1 1993/10/16 21:53:16 pk Exp $
*/
/*
* i386 run-time link editor entry points.
*/
#include <sys/syscall.h>
#define LCALL(x,y) .byte 0x9a ; .long y; .word x
.text
.globl _binder, _binder_entry
/*
* _rtl(int version, struct crt_ldso *crtp)
*/
#define FRAME 12 /* Size of stack frame */
_rtl: # crt0 calls us here
pushl %ebp # Allocate stack frame
movl %esp, %ebp
subl $FRAME, %esp
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
movl (-FRAME-4)(%ebp), %ebx # restore %ebx
leave # remove stack frame,
ret # let's rock
# 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
movl $0, %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
# Special system call stubs which return real and effective user and group
# id's. Saves overhead of making separate calls for each.
# !! Relies on compatability option in BSD 4.three-and-a-half
.globl _getreuid, _getregid
_getreuid:
lea SYS_getuid, %eax
LCALL(7,0)
jc out
movl 4(%esp), %ecx # get 1st arg
movl %eax, (%ecx) # put value in it
movl 8(%esp), %ecx # same for 2nd arg
movl %edx, (%ecx) #
ret # done
_getregid:
lea SYS_getgid, %eax
LCALL(7,0)
jc out
movl 4(%esp), %ecx # get 1st arg
movl %eax, (%ecx) # put value in it
movl 8(%esp), %ecx # same for 2nd arg
movl %edx, (%ecx) #
ret # done
out: jmp cerror@PLT # Call common error routine
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