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/* $OpenBSD: ldasm.S,v 1.18 2014/07/14 03:54:50 deraadt Exp $ */
/*
* Copyright (c) 2002,2004 Dale Rahn
* 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.
*
* 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.
*
*/
#define DL_DATA_SIZE (16*8) /* 16 * sizeof(ELF_Addr) */
#define DL_LOFF_OFFSET (7*8) /* index 7 */
#include <sys/syscall.h>
#include <machine/asm.h>
.text
.align 4
.globl _dl_start
.type _dl_start,@function
_dl_start:
movq %rsp, %r12 # save stack pointer for _rtld
subq $8, %rsp # align stack
andq $~15, %rsp
addq $8, %rsp
pushq %rbx # save ps_strings
subq $DL_DATA_SIZE, %rsp # allocate dl_data
leaq _DYNAMIC(%rip),%rdx # &_DYNAMIC
movq %rsp, %rsi # dl_data for dl_boot_bind
movq %r12, %rdi # load saved SP for dl_boot_bind
call _dl_boot_bind@PLT # _dl_boot_bind(sp,dl_data,dynamicp)
movq %rsp, %rcx # dl_data
movq DL_LOFF_OFFSET(%rsp), %rdx # loff from dl_data
movq (%r12), %rdi
leaq 16(%r12,%rdi,8), %rsi # envp
movq %r12, %rdi
addq $8,%rdi # argv
call _dl_boot@PLT # _dl_boot(argv,envp,loff,dl_data)
addq $DL_DATA_SIZE,%rsp # return dl_data
leaq _dl_dtors(%rip), %rdx # %rdx = cleanup
movq %r12, %rsp
jmp *%rax
.section ".text"
#define DL_SYSCALL(n) DL_SYSCALL2(n,n)
#define DL_SYSCALL2(n,c) \
.global __CONCAT(_dl_,n) ;\
.type __CONCAT(_dl_,n), @function ;\
.align 4 ;\
__CONCAT(_dl_,n): ;\
movl $(__CONCAT(SYS_,c)), %eax ;\
movq %rcx, %r10 ;\
syscall ;\
jb 1f ;\
ret
DL_SYSCALL(open)
DL_SYSCALL(fstat)
DL_SYSCALL(read)
DL_SYSCALL(write)
DL_SYSCALL(close)
DL_SYSCALL(issetugid)
DL_SYSCALL(getdents)
DL_SYSCALL(mprotect)
DL_SYSCALL(munmap)
DL_SYSCALL(gettimeofday)
DL_SYSCALL(exit)
DL_SYSCALL(readlink)
DL_SYSCALL(lstat)
DL_SYSCALL(utrace)
DL_SYSCALL(getentropy)
DL_SYSCALL(sendsyslog)
DL_SYSCALL2(getcwd,__getcwd)
DL_SYSCALL2(set_tcb,__set_tcb)
DL_SYSCALL2(_syscall,__syscall)
DL_SYSCALL2(sysctl,__sysctl)
1:
/* error: result = -errno; - handled here. */
neg %rax
ret
/* _dl_sigprocmask: does not handle NULL new set */
.align 4
.global _dl_sigprocmask
.type _dl_sigprocmask,@function
_dl_sigprocmask:
movl (%rsi),%esi # fetch indirect...
movl $SYS_sigprocmask, %eax
movq %rcx, %r10
syscall
jc 1b /* error: result = -errno */
testq %rdx,%rdx # test if old mask requested
jz 2f
movl %eax,(%rdx) # store old mask
xorq %rax,%rax
2: ret
.align 4
.global _dl_bind_start
.type _dl_bind_start,@function
_dl_bind_start:
.cfi_startproc
.cfi_adjust_cfa_offset 16
pushfq # save registers
.cfi_adjust_cfa_offset 8
/*.cfi_offset %rflags, -16 */
pushq %rax
.cfi_adjust_cfa_offset 8
.cfi_offset %rax, -24
pushq %rcx
.cfi_adjust_cfa_offset 8
.cfi_offset %rcx, -32
pushq %rdx
.cfi_adjust_cfa_offset 8
.cfi_offset %rdx, -40
pushq %rsi
.cfi_adjust_cfa_offset 8
.cfi_offset %rsi, -48
pushq %rdi
.cfi_adjust_cfa_offset 8
.cfi_offset %rdi, -56
pushq %r8
.cfi_adjust_cfa_offset 8
.cfi_offset %r8, -64
pushq %r9
.cfi_adjust_cfa_offset 8
.cfi_offset %r9, -72
pushq %r10
.cfi_adjust_cfa_offset 8
.cfi_offset %r10, -80
pushq %r11
.cfi_adjust_cfa_offset 8
.cfi_offset %r11, -88
movq 80(%rsp), %rdi # Copy of reloff
movq 88(%rsp), %rsi # Copy of obj
call _dl_bind@PLT # Call the binder
movq %rax,88(%rsp) # Store function to be called in obj
popq %r11 # restore registers
.cfi_adjust_cfa_offset -8
.cfi_restore %r11
popq %r10
.cfi_adjust_cfa_offset -8
.cfi_restore %r10
popq %r9
.cfi_adjust_cfa_offset -8
.cfi_restore %r9
popq %r8
.cfi_adjust_cfa_offset -8
.cfi_restore %r8
popq %rdi
.cfi_adjust_cfa_offset -8
.cfi_restore %rdi
popq %rsi
.cfi_adjust_cfa_offset -8
.cfi_restore %rsi
popq %rdx
.cfi_adjust_cfa_offset -8
.cfi_restore %rdx
popq %rcx
.cfi_adjust_cfa_offset -8
.cfi_restore %rcx
popq %rax
.cfi_adjust_cfa_offset -8
.cfi_restore %rax
popfq
.cfi_adjust_cfa_offset -8
/*.cfi_restore %rflags */
leaq 8(%rsp),%rsp # Discard reloff, do not change eflags
.cfi_adjust_cfa_offset -8
ret
.cfi_endproc
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