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 * Copyright (c) 2012, Joyent, Inc. All rights reserved. 33 */ 34 35 /* 36 * i386 specific setup routine - relocate ld.so's symbols, setup its 37 * environment, map in loadable sections of the executable. 38 * 39 * Takes base address ld.so was loaded at, address of ld.so's dynamic 40 * structure, address of process environment pointers, address of auxiliary 41 * vector and * argv[0] (process name). 42 * If errors occur, send process signal - otherwise 43 * return executable's entry point to the bootstrap routine. 44 */ 45 46 #include <signal.h> 47 #include <stdlib.h> 48 #include <sys/auxv.h> 49 #include <sys/types.h> 50 #include <sys/stat.h> 51 #include <link.h> 52 #include <dlfcn.h> 53 #include "_rtld.h" 54 #include "_audit.h" 55 #include "msg.h" 56 57 /* VARARGS */ 58 unsigned long 59 _setup(Boot *ebp, Dyn *ld_dyn) 60 { 61 ulong_t reladdr, relcount, ld_base = 0; 62 ulong_t relent = 0; 63 ulong_t strtab, soname, interp_base = 0; 64 char *_rt_name, **_envp, **_argv; 65 int _syspagsz = 0, fd = -1; 66 uint_t _flags = 0; 67 uint_t hwcap[2] = { 0, 0 }; 68 Dyn *dyn_ptr; 69 Phdr *phdr = NULL; 70 Rt_map *lmp; 71 auxv_t *auxv, *_auxv; 72 uid_t uid = (uid_t)-1, euid = (uid_t)-1; 73 gid_t gid = (gid_t)-1, egid = (gid_t)-1; 74 char *_platform = NULL, *_execname = NULL, *_emulator = NULL; 75 int auxflags = -1; 76 77 /* 78 * Scan the bootstrap structure to pick up the basics. 79 */ 80 for (; ebp->eb_tag != EB_NULL; ebp++) 81 switch (ebp->eb_tag) { 82 case EB_LDSO_BASE: 83 ld_base = (unsigned long)ebp->eb_un.eb_val; 84 break; 85 case EB_ARGV: 86 _argv = (char **)ebp->eb_un.eb_ptr; 87 break; 88 case EB_ENVP: 89 _envp = (char **)ebp->eb_un.eb_ptr; 90 break; 91 case EB_AUXV: 92 _auxv = (auxv_t *)ebp->eb_un.eb_ptr; 93 break; 94 case EB_PAGESIZE: 95 _syspagsz = (int)ebp->eb_un.eb_val; 96 break; 97 } 98 99 /* 100 * Search the aux. vector for the information passed by exec. 101 */ 102 for (auxv = _auxv; auxv->a_type != AT_NULL; auxv++) { 103 switch (auxv->a_type) { 104 case AT_EXECFD: 105 /* this is the old exec that passes a file descriptor */ 106 fd = (int)auxv->a_un.a_val; 107 break; 108 case AT_FLAGS: 109 /* processor flags (MAU available, etc) */ 110 _flags = auxv->a_un.a_val; 111 break; 112 case AT_PAGESZ: 113 /* system page size */ 114 _syspagsz = (int)auxv->a_un.a_val; 115 break; 116 case AT_PHDR: 117 /* address of the segment table */ 118 phdr = (Phdr *)auxv->a_un.a_ptr; 119 break; 120 case AT_BASE: 121 /* interpreter base address */ 122 if (ld_base == 0) 123 ld_base = auxv->a_un.a_val; 124 interp_base = auxv->a_un.a_val; 125 break; 126 case AT_SUN_UID: 127 /* effective user id for the executable */ 128 euid = (uid_t)auxv->a_un.a_val; 129 break; 130 case AT_SUN_RUID: 131 /* real user id for the executable */ 132 uid = (uid_t)auxv->a_un.a_val; 133 break; 134 case AT_SUN_GID: 135 /* effective group id for the executable */ 136 egid = (gid_t)auxv->a_un.a_val; 137 break; 138 case AT_SUN_RGID: 139 /* real group id for the executable */ 140 gid = (gid_t)auxv->a_un.a_val; 141 break; 142 case AT_SUN_PLATFORM: 143 /* platform name */ 144 _platform = auxv->a_un.a_ptr; 145 break; 146 case AT_SUN_EXECNAME: 147 /* full pathname of execed object */ 148 _execname = auxv->a_un.a_ptr; 149 break; 150 case AT_SUN_AUXFLAGS: 151 /* auxiliary flags */ 152 auxflags = (int)auxv->a_un.a_val; 153 break; 154 case AT_SUN_HWCAP: 155 /* hardware capabilities */ 156 hwcap[0] = (uint_t)auxv->a_un.a_val; 157 break; 158 case AT_SUN_HWCAP2: 159 /* hardware capabilities */ 160 hwcap[1] = (uint_t)auxv->a_un.a_val; 161 break; 162 case AT_SUN_EMULATOR: 163 /* name of emulation library, if any */ 164 _emulator = auxv->a_un.a_ptr; 165 break; 166 } 167 } 168 169 /* 170 * Get needed info from ld.so's dynamic structure. 171 */ 172 /* LINTED */ 173 dyn_ptr = (Dyn *)((char *)ld_dyn + ld_base); 174 for (ld_dyn = dyn_ptr; ld_dyn->d_tag != DT_NULL; ld_dyn++) { 175 switch (ld_dyn->d_tag) { 176 case DT_REL: 177 reladdr = ld_dyn->d_un.d_ptr + ld_base; 178 break; 179 case DT_RELCOUNT: 180 relcount = ld_dyn->d_un.d_val; 181 break; 182 case DT_RELENT: 183 relent = ld_dyn->d_un.d_val; 184 break; 185 case DT_STRTAB: 186 strtab = ld_dyn->d_un.d_ptr + ld_base; 187 break; 188 case DT_SONAME: 189 soname = ld_dyn->d_un.d_val; 190 break; 191 } 192 } 193 _rt_name = (char *)strtab + soname; 194 195 /* 196 * If we don't have a RELENT, just assume the size. 197 */ 198 if (relent == 0) 199 relent = sizeof (Rel); 200 201 /* 202 * As all global symbol references within ld.so.1 are protected 203 * (symbolic), only RELATIVE and JMPSLOT relocations should be left 204 * to process at runtime. Process all relative relocations now. 205 */ 206 for (; relcount; relcount--) { 207 ulong_t roffset; 208 209 roffset = ((Rel *)reladdr)->r_offset + ld_base; 210 *((ulong_t *)roffset) += ld_base; 211 reladdr += relent; 212 } 213 214 /* 215 * If an emulation library is being used, use that as the linker's 216 * effective executable name. The real executable is not linked by this 217 * linker. 218 */ 219 if (_emulator != NULL) { 220 _execname = _emulator; 221 rtld_flags2 |= RT_FL2_BRANDED; 222 } 223 224 /* 225 * Initialize the dyn_plt_ent_size field. It currently contains the 226 * size of the dyn_plt_template. It still needs to be aligned and have 227 * space for the 'dyn_data' area added. 228 */ 229 dyn_plt_ent_size = ROUND(dyn_plt_ent_size, M_WORD_ALIGN) + 230 sizeof (uintptr_t) + sizeof (uintptr_t) + sizeof (ulong_t) + 231 sizeof (ulong_t) + sizeof (Sym); 232 233 /* 234 * Continue with generic startup processing. 235 */ 236 if ((lmp = setup((char **)_envp, (auxv_t *)_auxv, _flags, _platform, 237 _syspagsz, _rt_name, ld_base, interp_base, fd, phdr, 238 _execname, _argv, uid, euid, gid, egid, NULL, auxflags, 239 hwcap)) == NULL) { 240 rtldexit(&lml_main, 1); 241 } 242 243 return (LM_ENTRY_PT(lmp)()); 244 } 245