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 (c) 1988 AT&T 24 * All Rights Reserved 25 * 26 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 27 * Use is subject to license terms. 28 */ 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 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 #include "_synonyms.h" 43 44 #include <signal.h> 45 #include <stdlib.h> 46 #include <sys/auxv.h> 47 #include <sys/types.h> 48 #include <sys/stat.h> 49 #include <link.h> 50 #include <dlfcn.h> 51 #include <debug.h> 52 #include "_rtld.h" 53 #include "_audit.h" 54 #include "msg.h" 55 56 extern int _end; 57 extern int _etext; 58 59 60 /* 61 * Stub routine to prevent atexit_init() being extracted from libc_pic.a on 62 * i386 and added to ld.so.1. We don't need it. 63 */ 64 void 65 atexit_init() 66 { 67 } 68 69 /* VARARGS */ 70 unsigned long 71 _setup(Boot * ebp, Dyn * ld_dyn) 72 { 73 unsigned long reladdr, relcount, ld_base = 0; 74 unsigned long relent = 0; 75 unsigned long strtab, soname, interp_base = 0; 76 char *_rt_name, **_envp, **_argv; 77 int _syspagsz = 0, fd = -1, dz_fd = FD_UNAVAIL; 78 uint_t _flags = 0, hwcap_1 = 0; 79 Dyn * dyn_ptr; 80 Phdr * phdr = 0; 81 Rt_map * lmp; 82 auxv_t *auxv, *_auxv; 83 uid_t uid = (uid_t)-1, euid = (uid_t)-1; 84 gid_t gid = (gid_t)-1, egid = (gid_t)-1; 85 char *_platform = 0, *_execname = 0, *_emulator = 0; 86 int auxflags = -1; 87 /* 88 * Scan the bootstrap structure to pick up the basics. 89 */ 90 for (; ebp->eb_tag != EB_NULL; ebp++) 91 switch (ebp->eb_tag) { 92 case EB_LDSO_BASE: 93 ld_base = (unsigned long)ebp->eb_un.eb_val; 94 break; 95 case EB_ARGV: 96 _argv = (char **)ebp->eb_un.eb_ptr; 97 break; 98 case EB_ENVP: 99 _envp = (char **)ebp->eb_un.eb_ptr; 100 break; 101 case EB_AUXV: 102 _auxv = (auxv_t *)ebp->eb_un.eb_ptr; 103 break; 104 case EB_DEVZERO: 105 dz_fd = (int)ebp->eb_un.eb_val; 106 break; 107 case EB_PAGESIZE: 108 _syspagsz = (int)ebp->eb_un.eb_val; 109 break; 110 } 111 112 /* 113 * Search the aux. vector for the information passed by exec. 114 */ 115 for (auxv = _auxv; auxv->a_type != AT_NULL; auxv++) { 116 switch (auxv->a_type) { 117 case AT_EXECFD: 118 /* this is the old exec that passes a file descriptor */ 119 fd = (int)auxv->a_un.a_val; 120 break; 121 case AT_FLAGS: 122 /* processor flags (MAU available, etc) */ 123 _flags = auxv->a_un.a_val; 124 break; 125 case AT_PAGESZ: 126 /* system page size */ 127 _syspagsz = (int)auxv->a_un.a_val; 128 break; 129 case AT_PHDR: 130 /* address of the segment table */ 131 phdr = (Phdr *)auxv->a_un.a_ptr; 132 break; 133 case AT_BASE: 134 /* interpreter base address */ 135 if (ld_base == 0) 136 ld_base = auxv->a_un.a_val; 137 interp_base = auxv->a_un.a_val; 138 break; 139 case AT_SUN_UID: 140 /* effective user id for the executable */ 141 euid = (uid_t)auxv->a_un.a_val; 142 break; 143 case AT_SUN_RUID: 144 /* real user id for the executable */ 145 uid = (uid_t)auxv->a_un.a_val; 146 break; 147 case AT_SUN_GID: 148 /* effective group id for the executable */ 149 egid = (gid_t)auxv->a_un.a_val; 150 break; 151 case AT_SUN_RGID: 152 /* real group id for the executable */ 153 gid = (gid_t)auxv->a_un.a_val; 154 break; 155 #ifdef AT_SUN_PLATFORM /* Defined on SunOS 5.5 & greater. */ 156 case AT_SUN_PLATFORM: 157 /* platform name */ 158 _platform = auxv->a_un.a_ptr; 159 break; 160 #endif 161 #ifdef AT_SUN_EXECNAME /* Defined on SunOS 5.6 & greater. */ 162 case AT_SUN_EXECNAME: 163 /* full pathname of execed object */ 164 _execname = auxv->a_un.a_ptr; 165 break; 166 #endif 167 #ifdef AT_SUN_AUXFLAGS /* At the behest of PSARC 2002/188 */ 168 case AT_SUN_AUXFLAGS: 169 auxflags = (int)auxv->a_un.a_val; 170 break; 171 #endif 172 #ifdef AT_SUN_HWCAP /* Hardware capabilities */ 173 case AT_SUN_HWCAP: 174 hwcap_1 = (uint_t)auxv->a_un.a_val; 175 break; 176 #endif 177 #ifdef AT_SUN_EMULATOR /* Emulation library name */ 178 case AT_SUN_EMULATOR: 179 /* name of emulation library, if any */ 180 _emulator = auxv->a_un.a_ptr; 181 break; 182 #endif 183 } 184 } 185 186 /* 187 * Get needed info from ld.so's dynamic structure. 188 */ 189 /* LINTED */ 190 dyn_ptr = (Dyn *)((char *)ld_dyn + ld_base); 191 for (ld_dyn = dyn_ptr; ld_dyn->d_tag != DT_NULL; ld_dyn++) { 192 switch (ld_dyn->d_tag) { 193 case DT_REL: 194 reladdr = ld_dyn->d_un.d_ptr + ld_base; 195 break; 196 case DT_RELCOUNT: 197 relcount = ld_dyn->d_un.d_val; 198 break; 199 case DT_RELENT: 200 relent = ld_dyn->d_un.d_val; 201 break; 202 case DT_STRTAB: 203 strtab = ld_dyn->d_un.d_ptr + ld_base; 204 break; 205 case DT_SONAME: 206 soname = ld_dyn->d_un.d_val; 207 break; 208 } 209 } 210 _rt_name = (char *)strtab + soname; 211 212 /* 213 * If we don't have a RELENT, just assume 214 * the size. 215 */ 216 if (relent == 0) 217 relent = sizeof (Rel); 218 219 /* 220 * Relocate all symbols in ld.so. 221 * 222 * Because ld.so.1 is built with -Bsymbolic there should only be 223 * RELATIVE and JMPSLOT relocations, both of which get relative 224 * additions against them. 225 */ 226 for (; relcount; relcount--) { 227 ulong_t roffset; 228 229 roffset = ((Rel *)reladdr)->r_offset + ld_base; 230 *((ulong_t *)roffset) += ld_base; 231 reladdr += relent; 232 } 233 234 /* 235 * If an emulation library is being used, use that as the linker's 236 * effective executable name. The real executable is not linked by this 237 * linker. 238 */ 239 if (_emulator != NULL) { 240 _execname = _emulator; 241 rtld_flags2 |= RT_FL2_BRANDED; 242 } 243 244 /* 245 * Initialize the dyn_plt_ent_size field. It currently contains the 246 * size of the dyn_plt_template. It still needs to be aligned and have 247 * space for the 'dyn_data' area added. 248 */ 249 dyn_plt_ent_size = ROUND(dyn_plt_ent_size, M_WORD_ALIGN) + 250 sizeof (uintptr_t) + sizeof (uintptr_t) + sizeof (ulong_t) + 251 sizeof (ulong_t) + sizeof (Sym); 252 253 /* 254 * Continue with generic startup processing. 255 */ 256 if ((lmp = setup((char **)_envp, (auxv_t *)_auxv, _flags, _platform, 257 _syspagsz, _rt_name, dyn_ptr, ld_base, interp_base, fd, phdr, 258 _execname, _argv, dz_fd, uid, euid, gid, egid, NULL, auxflags, 259 hwcap_1)) == NULL) { 260 rtldexit(&lml_main, 1); 261 } 262 263 return (LM_ENTRY_PT(lmp)()); 264 } 265