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 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 /* 30 * amd64 specific setup routine - relocate ld.so's symbols, setup its 31 * environment, map in loadable sections of the executable. 32 * 33 * Takes base address ld.so was loaded at, address of ld.so's dynamic 34 * structure, address of process environment pointers, address of auxiliary 35 * vector and * argv[0] (process name). 36 * If errors occur, send process signal - otherwise 37 * return executable's entry point to the bootstrap routine. 38 */ 39 40 #include <signal.h> 41 #include <stdlib.h> 42 #include <sys/auxv.h> 43 #include <sys/types.h> 44 #include <sys/stat.h> 45 #include <link.h> 46 #include <dlfcn.h> 47 #include <debug.h> 48 #include "_rtld.h" 49 #include "_audit.h" 50 #include "msg.h" 51 52 extern int _end; 53 extern int _etext; 54 55 56 /* VARARGS */ 57 unsigned long 58 _setup(Boot * ebp, Dyn * ld_dyn) 59 { 60 unsigned long reladdr, relacount, ld_base = 0; 61 unsigned long relaent = 0, pltrelsz = 0; 62 unsigned long strtab, soname, interp_base = 0; 63 char *_rt_name, **_envp, **_argv; 64 int _syspagsz = 0, fd = -1, dz_fd = FD_UNAVAIL; 65 uint_t _flags = 0, hwcap_1 = 0; 66 Dyn * dyn_ptr; 67 Phdr * phdr = 0; 68 Rt_map * lmp; 69 auxv_t *auxv, *_auxv; 70 uid_t uid = (uid_t)-1, euid = (uid_t)-1; 71 gid_t gid = (gid_t)-1, egid = (gid_t)-1; 72 char *_platform = 0, *_execname = 0, *_emulator = 0; 73 int auxflags = -1; 74 /* 75 * Scan the bootstrap structure to pick up the basics. 76 */ 77 for (; ebp->eb_tag != EB_NULL; ebp++) 78 switch (ebp->eb_tag) { 79 case EB_LDSO_BASE: 80 ld_base = (unsigned long)ebp->eb_un.eb_val; 81 break; 82 case EB_ARGV: 83 _argv = (char **)ebp->eb_un.eb_ptr; 84 break; 85 case EB_ENVP: 86 _envp = (char **)ebp->eb_un.eb_ptr; 87 break; 88 case EB_AUXV: 89 _auxv = (auxv_t *)ebp->eb_un.eb_ptr; 90 break; 91 case EB_DEVZERO: 92 dz_fd = (int)ebp->eb_un.eb_val; 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 auxflags = (int)auxv->a_un.a_val; 152 break; 153 case AT_SUN_HWCAP: 154 hwcap_1 = (uint_t)auxv->a_un.a_val; 155 break; 156 #ifdef AT_SUN_EMULATOR /* Emulation library name */ 157 case AT_SUN_EMULATOR: 158 /* name of emulation library, if any */ 159 _emulator = auxv->a_un.a_ptr; 160 break; 161 #endif 162 } 163 } 164 165 /* 166 * Get needed info from ld.so's dynamic structure. 167 */ 168 /* LINTED */ 169 dyn_ptr = (Dyn *)((char *)ld_dyn + ld_base); 170 for (ld_dyn = dyn_ptr; ld_dyn->d_tag != DT_NULL; ld_dyn++) { 171 switch (ld_dyn->d_tag) { 172 case DT_RELA: 173 reladdr = ld_dyn->d_un.d_ptr + ld_base; 174 break; 175 case DT_RELACOUNT: 176 relacount = ld_dyn->d_un.d_val; 177 break; 178 case DT_RELAENT: 179 relaent = ld_dyn->d_un.d_val; 180 break; 181 case DT_PLTRELSZ: 182 pltrelsz = ld_dyn->d_un.d_val; 183 break; 184 case DT_STRTAB: 185 strtab = ld_dyn->d_un.d_ptr + ld_base; 186 break; 187 case DT_SONAME: 188 soname = ld_dyn->d_un.d_val; 189 break; 190 } 191 } 192 _rt_name = (char *)strtab + soname; 193 194 /* 195 * If we don't have a RELAENT, just assume 196 * the size. 197 */ 198 if (relaent == 0) 199 relaent = sizeof (Rela); 200 /* 201 * Relocate all symbols in ld.so. 202 * 203 * Because ld.so.1 is built with -Bsymbolic there should only be 204 * RELATIVE and JMPSLOT relocations, both of which get relative 205 * additions against them. 206 */ 207 relacount += (pltrelsz / relaent); 208 for (; relacount; relacount--) { 209 ulong_t roffset; 210 211 roffset = ((Rela *)reladdr)->r_offset + ld_base; 212 *((ulong_t *)roffset) += ld_base + 213 ((Rela *)reladdr)->r_addend; 214 reladdr += relaent; 215 } 216 217 /* 218 * If an emulation library is being used, use that as the linker's 219 * effective executable name. The real executable is not linked by this 220 * linker. 221 */ 222 if (_emulator != NULL) { 223 _execname = _emulator; 224 rtld_flags2 |= RT_FL2_BRANDED; 225 } 226 227 /* 228 * Initialize the dyn_plt_ent_size field. It currently contains the 229 * size of the dyn_plt_template. It still needs to be aligned and have 230 * space for the 'dyn_data' area added. 231 */ 232 dyn_plt_ent_size = ROUND(dyn_plt_ent_size, M_WORD_ALIGN) + 233 sizeof (uintptr_t) + sizeof (uintptr_t) + sizeof (ulong_t) + 234 sizeof (ulong_t) + sizeof (Sym); 235 236 /* 237 * Continue with generic startup processing. 238 */ 239 if ((lmp = setup((char **)_envp, (auxv_t *)_auxv, _flags, _platform, 240 _syspagsz, _rt_name, dyn_ptr, ld_base, interp_base, fd, phdr, 241 _execname, _argv, dz_fd, uid, euid, gid, egid, NULL, auxflags, 242 hwcap_1)) == NULL) { 243 rtldexit(&lml_main, 1); 244 } 245 246 return (LM_ENTRY_PT(lmp)()); 247 } 248