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 * amd64 specific setup routine - relocate ld.so's symbols, setup its 29 * environment, map in loadable sections of the executable. 30 * 31 * Takes base address ld.so was loaded at, address of ld.so's dynamic 32 * structure, address of process environment pointers, address of auxiliary 33 * vector and * argv[0] (process name). 34 * If errors occur, send process signal - otherwise 35 * return executable's entry point to the bootstrap routine. 36 */ 37 38 #include <signal.h> 39 #include <stdlib.h> 40 #include <sys/auxv.h> 41 #include <sys/types.h> 42 #include <sys/stat.h> 43 #include <link.h> 44 #include <dlfcn.h> 45 #include "_rtld.h" 46 #include "_audit.h" 47 #include "msg.h" 48 49 /* VARARGS */ 50 unsigned long 51 _setup(Boot *ebp, Dyn *ld_dyn) 52 { 53 ulong_t reladdr, relacount, ld_base = 0; 54 ulong_t relaent = 0, pltrelsz = 0; 55 ulong_t strtab, soname, interp_base = 0; 56 char *_rt_name, **_envp, **_argv; 57 int _syspagsz = 0, fd = -1; 58 uint_t _flags = 0, hwcap_1 = 0; 59 Dyn *dyn_ptr; 60 Phdr *phdr = NULL; 61 Rt_map *lmp; 62 auxv_t *auxv, *_auxv; 63 uid_t uid = (uid_t)-1, euid = (uid_t)-1; 64 gid_t gid = (gid_t)-1, egid = (gid_t)-1; 65 char *_platform = NULL, *_execname = NULL, *_emulator = NULL; 66 int auxflags = -1; 67 68 /* 69 * Scan the bootstrap structure to pick up the basics. 70 */ 71 for (; ebp->eb_tag != EB_NULL; ebp++) 72 switch (ebp->eb_tag) { 73 case EB_LDSO_BASE: 74 ld_base = (unsigned long)ebp->eb_un.eb_val; 75 break; 76 case EB_ARGV: 77 _argv = (char **)ebp->eb_un.eb_ptr; 78 break; 79 case EB_ENVP: 80 _envp = (char **)ebp->eb_un.eb_ptr; 81 break; 82 case EB_AUXV: 83 _auxv = (auxv_t *)ebp->eb_un.eb_ptr; 84 break; 85 case EB_PAGESIZE: 86 _syspagsz = (int)ebp->eb_un.eb_val; 87 break; 88 } 89 90 /* 91 * Search the aux. vector for the information passed by exec. 92 */ 93 for (auxv = _auxv; auxv->a_type != AT_NULL; auxv++) { 94 switch (auxv->a_type) { 95 case AT_EXECFD: 96 /* this is the old exec that passes a file descriptor */ 97 fd = (int)auxv->a_un.a_val; 98 break; 99 case AT_FLAGS: 100 /* processor flags (MAU available, etc) */ 101 _flags = auxv->a_un.a_val; 102 break; 103 case AT_PAGESZ: 104 /* system page size */ 105 _syspagsz = (int)auxv->a_un.a_val; 106 break; 107 case AT_PHDR: 108 /* address of the segment table */ 109 phdr = (Phdr *)auxv->a_un.a_ptr; 110 break; 111 case AT_BASE: 112 /* interpreter base address */ 113 if (ld_base == 0) 114 ld_base = auxv->a_un.a_val; 115 interp_base = auxv->a_un.a_val; 116 break; 117 case AT_SUN_UID: 118 /* effective user id for the executable */ 119 euid = (uid_t)auxv->a_un.a_val; 120 break; 121 case AT_SUN_RUID: 122 /* real user id for the executable */ 123 uid = (uid_t)auxv->a_un.a_val; 124 break; 125 case AT_SUN_GID: 126 /* effective group id for the executable */ 127 egid = (gid_t)auxv->a_un.a_val; 128 break; 129 case AT_SUN_RGID: 130 /* real group id for the executable */ 131 gid = (gid_t)auxv->a_un.a_val; 132 break; 133 case AT_SUN_PLATFORM: 134 /* platform name */ 135 _platform = auxv->a_un.a_ptr; 136 break; 137 case AT_SUN_EXECNAME: 138 /* full pathname of execed object */ 139 _execname = auxv->a_un.a_ptr; 140 break; 141 case AT_SUN_AUXFLAGS: 142 /* auxiliary flags */ 143 auxflags = (int)auxv->a_un.a_val; 144 break; 145 case AT_SUN_HWCAP: 146 /* hardware capabilities */ 147 hwcap_1 = (uint_t)auxv->a_un.a_val; 148 break; 149 case AT_SUN_EMULATOR: 150 /* name of emulation library, if any */ 151 _emulator = auxv->a_un.a_ptr; 152 break; 153 } 154 } 155 156 /* 157 * Get needed info from ld.so's dynamic structure. 158 */ 159 /* LINTED */ 160 dyn_ptr = (Dyn *)((char *)ld_dyn + ld_base); 161 for (ld_dyn = dyn_ptr; ld_dyn->d_tag != DT_NULL; ld_dyn++) { 162 switch (ld_dyn->d_tag) { 163 case DT_RELA: 164 reladdr = ld_dyn->d_un.d_ptr + ld_base; 165 break; 166 case DT_RELACOUNT: 167 relacount = ld_dyn->d_un.d_val; 168 break; 169 case DT_RELAENT: 170 relaent = ld_dyn->d_un.d_val; 171 break; 172 case DT_PLTRELSZ: 173 pltrelsz = ld_dyn->d_un.d_val; 174 break; 175 case DT_STRTAB: 176 strtab = ld_dyn->d_un.d_ptr + ld_base; 177 break; 178 case DT_SONAME: 179 soname = ld_dyn->d_un.d_val; 180 break; 181 } 182 } 183 _rt_name = (char *)strtab + soname; 184 185 /* 186 * If we don't have a RELAENT, just assume the size. 187 */ 188 if (relaent == 0) 189 relaent = sizeof (Rela); 190 191 /* 192 * As all global symbol references within ld.so.1 are protected 193 * (symbolic), only RELATIVE and JMPSLOT relocations should be left 194 * to process at runtime. Process all relocations now. 195 */ 196 relacount += (pltrelsz / relaent); 197 for (; relacount; relacount--) { 198 ulong_t roffset; 199 200 roffset = ((Rela *)reladdr)->r_offset + ld_base; 201 *((ulong_t *)roffset) += ld_base + 202 ((Rela *)reladdr)->r_addend; 203 reladdr += relaent; 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