usr/src/cmd/sgs/rtld/sparc/_setup.c

   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  * SPARC 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 #ifdef A_OUT
  57 #include        "_a.out.h"
  58 #endif /* A_OUT */
  59
  60 /* VARARGS */
  61 unsigned long
  62 _setup(Boot *ebp, Dyn *ld_dyn)
  63 {
  64         ulong_t         reladdr, relacount, ld_base = 0;
  65         ulong_t         relaent = 0;
  66         ulong_t         strtab, soname, interp_base = 0;
  67         char            *_rt_name, **_envp, **_argv;
  68         int             _syspagsz = 0, fd = -1;
  69         uint_t          _flags = 0;
  70         uint_t          hwcap[2] = { 0, 0 };
  71         Dyn             *dyn_ptr;
  72         Phdr            *phdr = NULL;
  73         Rt_map          *lmp;
  74         auxv_t          *auxv, *_auxv;
  75         uid_t           uid = (uid_t)-1, euid = (uid_t)-1;
  76         gid_t           gid = (gid_t)-1, egid = (gid_t)-1;
  77         char            *_platform = NULL, *_execname = NULL, *_emulator = NULL;
  78         int             auxflags = -1;
  79 #ifdef  A_OUT
  80         void            *aoutdyn = NULL;
  81 #endif  /* A_OUT */
  82
  83         /*
  84          * Scan the bootstrap structure to pick up the basics.
  85          */
  86         for (; ebp->eb_tag != EB_NULL; ebp++)
  87                 switch (ebp->eb_tag) {
  88                 case EB_DYNAMIC:
  89 #ifdef A_OUT
  90                         aoutdyn = (Link_dynamic *)ebp->eb_un.eb_val;
  91 #endif /* A_OUT */
  92                         break;
  93                 case EB_LDSO_BASE:
  94                         ld_base = (unsigned long)ebp->eb_un.eb_val;
  95                         break;
  96                 case EB_ARGV:
  97                         _argv = (char **)ebp->eb_un.eb_ptr;
  98                         break;
  99                 case EB_ENVP:
 100                         _envp = (char **)ebp->eb_un.eb_ptr;
 101                         break;
 102                 case EB_AUXV:
 103                         _auxv = (auxv_t *)ebp->eb_un.eb_ptr;
 104                         break;
 105                 case EB_PAGESIZE:
 106                         _syspagsz = (int)ebp->eb_un.eb_val;
 107                         break;
 108                 }
 109
 110         /*
 111          * Search the aux. vector for the information passed by exec.
 112          */
 113         for (auxv = _auxv; auxv->a_type != AT_NULL; auxv++) {
 114                 switch (auxv->a_type) {
 115                 case AT_EXECFD:
 116                         /* this is the old exec that passes a file descriptor */
 117                         fd = (int)auxv->a_un.a_val;
 118                         break;
 119                 case AT_FLAGS:
 120                         /* processor flags (MAU available, etc) */
 121                         _flags = auxv->a_un.a_val;
 122                         break;
 123                 case AT_PAGESZ:
 124                         /* system page size */
 125                         _syspagsz = (int)auxv->a_un.a_val;
 126                         break;
 127                 case AT_PHDR:
 128                         /* address of the segment table */
 129                         phdr = (Phdr *)auxv->a_un.a_ptr;
 130                         break;
 131                 case AT_BASE:
 132                         /* interpreter base address */
 133                         if (ld_base == 0)
 134                                 ld_base = auxv->a_un.a_val;
 135                         interp_base = auxv->a_un.a_val;
 136                         break;
 137                 case AT_SUN_UID:
 138                         /* effective user id for the executable */
 139                         euid = (uid_t)auxv->a_un.a_val;
 140                         break;
 141                 case AT_SUN_RUID:
 142                         /* real user id for the executable */
 143                         uid = (uid_t)auxv->a_un.a_val;
 144                         break;
 145                 case AT_SUN_GID:
 146                         /* effective group id for the executable */
 147                         egid = (gid_t)auxv->a_un.a_val;
 148                         break;
 149                 case AT_SUN_RGID:
 150                         /* real group id for the executable */
 151                         gid = (gid_t)auxv->a_un.a_val;
 152                         break;
 153                 case AT_SUN_PLATFORM:
 154                         /* platform name */
 155                         _platform = auxv->a_un.a_ptr;
 156                         break;
 157                 case AT_SUN_EXECNAME:
 158                         /* full pathname of execed object */
 159                         _execname = auxv->a_un.a_ptr;
 160                         break;
 161                 case AT_SUN_AUXFLAGS:
 162                         /* auxiliary flags */
 163                         auxflags = (int)auxv->a_un.a_val;
 164                         break;
 165                 case AT_SUN_HWCAP:
 166                         /* hardware capabilities */
 167                         hwcap[0] = (uint_t)auxv->a_un.a_val;
 168                         break;
 169                 case AT_SUN_HWCAP2:
 170                         /* hardware capabilities */
 171                         hwcap[1] = (uint_t)auxv->a_un.a_val;
 172                         break;
 173                 case AT_SUN_EMULATOR:
 174                         /* name of emulation library, if any */
 175                         _emulator = auxv->a_un.a_ptr;
 176                         break;
 177                 }
 178         }
 179
 180         /*
 181          * Get needed info from ld.so's dynamic structure.
 182          */
 183         /* LINTED */
 184         dyn_ptr = (Dyn *)((char *)ld_dyn + ld_base);
 185         for (ld_dyn = dyn_ptr; ld_dyn->d_tag != DT_NULL; ld_dyn++) {
 186                 switch (ld_dyn->d_tag) {
 187                 case DT_RELA:
 188                         reladdr = ld_dyn->d_un.d_ptr + ld_base;
 189                         break;
 190                 case DT_RELACOUNT:
 191                         relacount = ld_dyn->d_un.d_val;
 192                         break;
 193                 case DT_RELAENT:
 194                         relaent = ld_dyn->d_un.d_val;
 195                         break;
 196                 case DT_STRTAB:
 197                         strtab = ld_dyn->d_un.d_ptr + ld_base;
 198                         break;
 199                 case DT_SONAME:
 200                         soname = ld_dyn->d_un.d_val;
 201                         break;
 202                 }
 203         }
 204         _rt_name = (char *)strtab + soname;
 205
 206         /*
 207          * If we don't have a RELAENT, just assume the size.
 208          */
 209         if (relaent == 0)
 210                 relaent = sizeof (Rela);
 211
 212         /*
 213          * As all global symbol references within ld.so.1 are protected
 214          * (symbolic), only RELATIVE and JMPSLOT relocations should be left
 215          * to process at runtime.  Process all relative relocations now.
 216          */
 217         for (; relacount; relacount--) {
 218                 ulong_t roffset;
 219
 220                 roffset = ((Rela *)reladdr)->r_offset + ld_base;
 221                 *((ulong_t *)roffset) = ld_base +
 222                     ((Rela *)reladdr)->r_addend;
 223                 reladdr += relaent;
 224         }
 225
 226         /*
 227          * If an emulation library is being used, use that as the linker's
 228          * effective executable name. The real executable is not linked by this
 229          * linker.
 230          */
 231         if (_emulator != NULL) {
 232                 _execname = _emulator;
 233                 rtld_flags2 |= RT_FL2_BRANDED;
 234         }
 235
 236         /*
 237          * Continue with generic startup processing.
 238          */
 239         /* BEGIN CSTYLED */
 240         if ((lmp = setup((char **)_envp, (auxv_t *)_auxv, _flags, _platform,
 241             _syspagsz, _rt_name, ld_base, interp_base, fd, phdr,
 242             _execname, _argv, uid, euid, gid, egid,
 243 #ifdef  A_OUT
 244             aoutdyn, auxflags, hwcap)) == NULL) {
 245 #else
 246             /* CSTYLED */
 247             NULL, auxflags, hwcap)) == NULL) {
 248 #endif  /* A_OUT */
 249                 rtldexit(&lml_main, 1);
 250         }
 251         /* END CSTYLED */
 252
 253         return (LM_ENTRY_PT(lmp)());
 254 }