1/* $NetBSD: rtld_start.S,v 1.14 2011/01/16 01:22:29 matt Exp $ */ 2 3/*- 4 * Copyright (C) 1998 Tsubai Masanari 5 * Portions copyright 2002 Charles M. Hannum <root@ihack.net> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31#include <machine/asm.h> 32 33 .globl _rtld_start 34 .globl _rtld 35 36 .text 37 38_rtld_start: 39 stwu %r1,-48(%r1) 40 stw %r3,12(%r1) # argc 41 stw %r4,16(%r1) # argv 42 stw %r5,20(%r1) # envp 43/* stw %r6,24(%r1) # obj (always 0) */ 44/* stw %r7,28(%r1) # cleanup (always 0) */ 45 stw %r8,32(%r1) # ps_strings 46 47 bcl 20,31,1f 481: mflr %r30 49 mr %r3,%r30 # save for _DYNAMIC 50 addis %r30,%r30,_GLOBAL_OFFSET_TABLE_-1b@ha 51 addi %r30,%r30,_GLOBAL_OFFSET_TABLE_-1b@l 52 addis %r3,%r3,_DYNAMIC-1b@ha # get _DYNAMIC actual address 53 addi %r3,%r3,_DYNAMIC-1b@l 54 lwz %r28,0(%r30) # get base-relative &_DYNAMIC 55 sub %r28,%r3,%r28 # r28 = relocbase 56 mr %r4,%r28 # r4 = relocbase 57 bl _rtld_relocate_nonplt_self 58 59 lwz %r3,16(%r1) 60 addi %r3,%r3,-12 # sp = &argv[-3] /* XXX */ 61 mr %r4,%r28 # r4 = relocbase 62 bl _rtld # _start = _rtld(sp, relocbase) 63 mtlr %r3 64 65 lwz %r3,12(%r1) # argc 66 lwz %r4,16(%r1) # argv 67 lwz %r5,20(%r1) # envp 68 lwz %r6,-8(%r4) # obj = sp[1] (== argv[-2]) 69 lwz %r7,-12(%r4) # cleanup = sp[0] (== argv[-3]) 70 lwz %r8,32(%r1) # ps_strings 71 72 addi %r1,%r1,48 73 blrl # _start(argc, argv, envp, obj, cleanup, ps_strings) 74 75 li %r0,1 # _exit() 76 sc 77 78END(_rtld_start) 79 80 .globl _rtld_bind 81 82/* 83 * secure-plt expects %r11 to be the offset to the rela entry. 84 * bss-plt expects %r11 to be index of the rela entry. 85 * So for bss-plt, we multiply the index by 12 to get the offset. 86 */ 87ENTRY_NOPROFILE(_rtld_bind_bssplt_start) 88 slwi %r11,%r11,2 89 add %r0,%r11,%r11 90 add %r11,%r11,%r0 91ENTRY_NOPROFILE(_rtld_bind_secureplt_start) 92 stwu %r1,-160(%r1) 93 94 stw %r0,20(%r1) 95 mflr %r0 96 stw %r0,16(%r1) # save lr 97 mfcr %r0 98 stw %r0,12(%r1) # save cr 99 stmw %r3,24(%r1) # save r3-r31 100 101 mr %r3,%r12 # obj 102 mr %r4,%r11 # reloff 103 bl _rtld_bind # _rtld_bind(obj, reloff) 104 mtctr %r3 105 106 lmw %r3,24(%r1) # load r3-r31 107 lwz %r0,12(%r1) # restore cr 108 mtcr %r0 109 lwz %r0,16(%r1) # restore lr 110 mtlr %r0 111 lwz %r0,20(%r1) 112 113 addi %r1,%r1,160 114 bctr 115END(_rtld_bind_start) 116 117 .globl _rtld_powerpc_pltcall 118 .globl _rtld_powerpc_pltresolve 119 120_rtld_powerpc_pltcall: 121 slwi %r11,%r11,2 122 addis %r11,%r11,0 # addis 11,11,jmptab@ha 123 lwz %r11,0(%r11) # lwz 11,jmptab@l(11) 124 mtctr %r11 125 bctr 126 127_rtld_powerpc_pltresolve: 128 lis %r12,0 # lis 12,_rtld_bind_bssplt_start@ha 129 addi %r12,%r12,0 # addi 12,12,_rtld_bind_bssplt_start@l 130 mtctr %r12 131 lis %r12,0 # lis 12,obj@ha 132 addi %r12,%r12,0 # addi 12,12,obj@l 133 bctr 134