1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* 28 * Copyright (c) 1988 AT&T 29 * All Rights Reserved 30 */ 31 32 /* 33 * i386 specific setup routine - relocate ld.so's symbols, setup its 34 * environment, map in loadable sections of the executable. 35 * 36 * Takes base address ld.so was loaded at, address of ld.so's dynamic 37 * structure, address of process environment pointers, address of auxiliary 38 * vector and * argv[0] (process name). 39 * If errors occur, send process signal - otherwise 40 * return executable's entry point to the bootstrap routine. 41 */ 42 43 #include <signal.h> 44 #include <stdlib.h> 45 #include <sys/auxv.h> 46 #include <sys/types.h> 47 #include <sys/stat.h> 48 #include <link.h> 49 #include <dlfcn.h> 50 #include "_rtld.h" 51 #include "_audit.h" 52 #include "msg.h" 53 54 /* VARARGS */ 55 unsigned long 56 _setup(Boot *ebp, Dyn *ld_dyn) 57 { 58 ulong_t reladdr, relcount, ld_base = 0; 59 ulong_t relent = 0; 60 ulong_t strtab, soname, interp_base = 0; 61 char *_rt_name, **_envp, **_argv; 62 int _syspagsz = 0, fd = -1; 63 uint_t _flags = 0, hwcap_1 = 0; 64 Dyn *dyn_ptr; 65 Phdr *phdr = NULL; 66 Rt_map *lmp; 67 auxv_t *auxv, *_auxv; 68 uid_t uid = (uid_t)-1, euid = (uid_t)-1; 69 gid_t gid = (gid_t)-1, egid = (gid_t)-1; 70 char *_platform = NULL, *_execname = NULL, *_emulator = NULL; 71 int auxflags = -1; 72 73 /* 74 * Scan the bootstrap structure to pick up the basics. 75 */ 76 for (; ebp->eb_tag != EB_NULL; ebp++) 77 switch (ebp->eb_tag) { 78 case EB_LDSO_BASE: 79 ld_base = (unsigned long)ebp->eb_un.eb_val; 80 break; 81 case EB_ARGV: 82 _argv = (char **)ebp->eb_un.eb_ptr; 83 break; 84 case EB_ENVP: 85 _envp = (char **)ebp->eb_un.eb_ptr; 86 break; 87 case EB_AUXV: 88 _auxv = (auxv_t *)ebp->eb_un.eb_ptr; 89 break; 90 case EB_PAGESIZE: 91 _syspagsz = (int)ebp->eb_un.eb_val; 92 break; 93 } 94 95 /* 96 * Search the aux. vector for the information passed by exec. 97 */ 98 for (auxv = _auxv; auxv->a_type != AT_NULL; auxv++) { 99 switch (auxv->a_type) { 100 case AT_EXECFD: 101 /* this is the old exec that passes a file descriptor */ 102 fd = (int)auxv->a_un.a_val; 103 break; 104 case AT_FLAGS: 105 /* processor flags (MAU available, etc) */ 106 _flags = auxv->a_un.a_val; 107 break; 108 case AT_PAGESZ: 109 /* system page size */ 110 _syspagsz = (int)auxv->a_un.a_val; 111 break; 112 case AT_PHDR: 113 /* address of the segment table */ 114 phdr = (Phdr *)auxv->a_un.a_ptr; 115 break; 116 case AT_BASE: 117 /* interpreter base address */ 118 if (ld_base == 0) 119 ld_base = auxv->a_un.a_val; 120 interp_base = auxv->a_un.a_val; 121 break; 122 case AT_SUN_UID: 123 /* effective user id for the executable */ 124 euid = (uid_t)auxv->a_un.a_val; 125 break; 126 case AT_SUN_RUID: 127 /* real user id for the executable */ 128 uid = (uid_t)auxv->a_un.a_val; 129 break; 130 case AT_SUN_GID: 131 /* effective group id for the executable */ 132 egid = (gid_t)auxv->a_un.a_val; 133 break; 134 case AT_SUN_RGID: 135 /* real group id for the executable */ 136 gid = (gid_t)auxv->a_un.a_val; 137 break; 138 case AT_SUN_PLATFORM: 139 /* platform name */ 140 _platform = auxv->a_un.a_ptr; 141 break; 142 case AT_SUN_EXECNAME: 143 /* full pathname of execed object */ 144 _execname = auxv->a_un.a_ptr; 145 break; 146 case AT_SUN_AUXFLAGS: 147 /* auxiliary flags */ 148 auxflags = (int)auxv->a_un.a_val; 149 break; 150 case AT_SUN_HWCAP: 151 /* hardware capabilities */ 152 hwcap_1 = (uint_t)auxv->a_un.a_val; 153 break; 154 case AT_SUN_EMULATOR: 155 /* name of emulation library, if any */ 156 _emulator = auxv->a_un.a_ptr; 157 break; 158 } 159 } 160 161 /* 162 * Get needed info from ld.so's dynamic structure. 163 */ 164 /* LINTED */ 165 dyn_ptr = (Dyn *)((char *)ld_dyn + ld_base); 166 for (ld_dyn = dyn_ptr; ld_dyn->d_tag != DT_NULL; ld_dyn++) { 167 switch (ld_dyn->d_tag) { 168 case DT_REL: 169 reladdr = ld_dyn->d_un.d_ptr + ld_base; 170 break; 171 case DT_RELCOUNT: 172 relcount = ld_dyn->d_un.d_val; 173 break; 174 case DT_RELENT: 175 relent = ld_dyn->d_un.d_val; 176 break; 177 case DT_STRTAB: 178 strtab = ld_dyn->d_un.d_ptr + ld_base; 179 break; 180 case DT_SONAME: 181 soname = ld_dyn->d_un.d_val; 182 break; 183 } 184 } 185 _rt_name = (char *)strtab + soname; 186 187 /* 188 * If we don't have a RELENT, just assume the size. 189 */ 190 if (relent == 0) 191 relent = sizeof (Rel); 192 193 /* 194 * As all global symbol references within ld.so.1 are protected 195 * (symbolic), only RELATIVE and JMPSLOT relocations should be left 196 * to process at runtime. Process all relative relocations now. 197 */ 198 for (; relcount; relcount--) { 199 ulong_t roffset; 200 201 roffset = ((Rel *)reladdr)->r_offset + ld_base; 202 *((ulong_t *)roffset) += ld_base; 203 reladdr += relent; 204 } 205 206 /* 207 * If an emulation library is being used, use that as the linker's 208 * effective executable name. The real executable is not linked by this 209 * linker. 210 */ 211 if (_emulator != NULL) { 212 _execname = _emulator; 213 rtld_flags2 |= RT_FL2_BRANDED; 214 } 215 216 /* 217 * Initialize the dyn_plt_ent_size field. It currently contains the 218 * size of the dyn_plt_template. It still needs to be aligned and have 219 * space for the 'dyn_data' area added. 220 */ 221 dyn_plt_ent_size = ROUND(dyn_plt_ent_size, M_WORD_ALIGN) + 222 sizeof (uintptr_t) + sizeof (uintptr_t) + sizeof (ulong_t) + 223 sizeof (ulong_t) + sizeof (Sym); 224 225 /* 226 * Continue with generic startup processing. 227 */ 228 if ((lmp = setup((char **)_envp, (auxv_t *)_auxv, _flags, _platform, 229 _syspagsz, _rt_name, ld_base, interp_base, fd, phdr, 230 _execname, _argv, uid, euid, gid, egid, NULL, auxflags, 231 hwcap_1)) == NULL) { 232 rtldexit(&lml_main, 1); 233 } 234 235 return (LM_ENTRY_PT(lmp)()); 236 } 237