sod.c revision 1.14
1/* $OpenBSD: sod.c,v 1.14 2002/07/12 20:18:30 drahn Exp $ */ 2 3/* 4 * Copyright (c) 1993 Paul Kranenburg 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Paul Kranenburg. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 * 32 */ 33 34#include <sys/types.h> 35#include <sys/syslimits.h> 36#include <stdio.h> 37#include <fcntl.h> 38#include <nlist.h> 39#include <link.h> 40#include <machine/exec.h> 41#include <sys/mman.h> 42#include <string.h> 43#include <stdlib.h> 44#include <unistd.h> 45#include <syscall.h> 46 47#include "archdep.h" 48#include "util.h" 49#include "sod.h" 50 51#define PAGSIZ __LDPGSZ 52int _dl_hinthash(char *cp, int vmajor, int vminor); 53 54/* 55 * Populate sod struct for dlopen's call to map_object 56 */ 57void 58_dl_build_sod(name, sodp) 59 const char *name; 60 struct sod *sodp; 61{ 62 unsigned int tuplet; 63 int major, minor; 64 char *realname, *tok, *etok, *cp; 65 66 /* default is an absolute or relative path */ 67 sodp->sod_name = (long)_dl_strdup(name); /* strtok is destructive */ 68 sodp->sod_library = 0; 69 sodp->sod_major = sodp->sod_minor = 0; 70 71 /* does it look like /^lib/ ? */ 72 if (_dl_strncmp((char *)sodp->sod_name, "lib", 3) != 0) 73 return; 74 75 /* is this a filename? */ 76 if (_dl_strchr((char *)sodp->sod_name, '/')) 77 return; 78 79 /* skip over 'lib' */ 80 cp = (char *)sodp->sod_name + 3; 81 82 /* dot guardian */ 83 if ((_dl_strchr(cp, '.') == NULL) || (*(cp+_dl_strlen(cp)-1) == '.')) 84 return; 85 86 /* default */ 87 major = minor = -1; 88 89 realname = NULL; 90 /* loop through name - parse skipping name */ 91 for (tuplet = 0; (tok = strsep(&cp, ".")) != NULL; tuplet++) { 92 switch (tuplet) { 93 case 0: 94 /* removed 'lib' and extensions from name */ 95 realname = tok; 96 break; 97 case 1: 98 /* 'so' extension */ 99 if (_dl_strcmp(tok, "so") != 0) 100 goto backout; 101 break; 102 case 2: 103 /* major version extension */ 104 major = strtol(tok, &etok, 10); 105 if (*tok == '\0' || *etok != '\0') 106 goto backout; 107 break; 108 case 3: 109 /* minor version extension */ 110 minor = strtol(tok, &etok, 10); 111 if (*tok == '\0' || *etok != '\0') 112 goto backout; 113 break; 114 /* if we get here, it must be weird */ 115 default: 116 goto backout; 117 } 118 } 119 if (realname == NULL) { 120 goto backout; 121 } 122 cp = (char *)sodp->sod_name; 123 sodp->sod_name = (long)_dl_strdup(realname); 124 _dl_free(cp); 125 sodp->sod_library = 1; 126 sodp->sod_major = major; 127 sodp->sod_minor = minor; 128 return; 129 130backout: 131 _dl_free((char *)sodp->sod_name); 132 sodp->sod_name = (long)_dl_strdup(name); 133} 134 135static int hfd; 136static long hsize; 137static struct hints_header *hheader = NULL; 138static struct hints_bucket *hbuckets; 139static char *hstrtab; 140char *_dl_hint_search_path = NULL; 141 142#define HINTS_VALID (hheader != NULL && hheader != (struct hints_header *)-1) 143 144void 145_dl_maphints() 146{ 147 caddr_t addr; 148 149 if ((hfd = _dl_open(_PATH_LD_HINTS, O_RDONLY)) < 0) { 150 hheader = (struct hints_header *)-1; 151 return; 152 } 153 154 hsize = PAGSIZ; 155 addr = (void *) _dl_mmap(0, hsize, PROT_READ, MAP_PRIVATE, hfd, 0); 156 157 if (addr == MAP_FAILED) { 158 _dl_close(hfd); 159 hheader = (struct hints_header *)-1; 160 return; 161 } 162 163 hheader = (struct hints_header *)addr; 164 if (HH_BADMAG(*hheader)) { 165 _dl_munmap(addr, hsize); 166 _dl_close(hfd); 167 hheader = (struct hints_header *)-1; 168 return; 169 } 170 171 if (hheader->hh_version != LD_HINTS_VERSION_1 && 172 hheader->hh_version != LD_HINTS_VERSION_2) { 173 _dl_munmap(addr, hsize); 174 _dl_close(hfd); 175 hheader = (struct hints_header *)-1; 176 return; 177 } 178 179 if (hheader->hh_ehints > hsize) { 180 if ((caddr_t)_dl_mmap(addr+hsize, hheader->hh_ehints - hsize, 181 PROT_READ, MAP_PRIVATE|MAP_FIXED, 182 hfd, hsize) != (caddr_t)(addr+hsize)) { 183 _dl_munmap((caddr_t)hheader, hsize); 184 _dl_close(hfd); 185 hheader = (struct hints_header *)-1; 186 return; 187 } 188 } 189 190 hbuckets = (struct hints_bucket *)(addr + hheader->hh_hashtab); 191 hstrtab = (char *)(addr + hheader->hh_strtab); 192 if (hheader->hh_version >= LD_HINTS_VERSION_2) 193 _dl_hint_search_path = hstrtab + hheader->hh_dirlist; 194 195 /* close the file descriptor, leaving the hints mapped */ 196 _dl_close(hfd); 197} 198 199char * 200_dl_findhint(name, major, minor, prefered_path) 201 char *name; 202 int major, minor; 203 char *prefered_path; 204{ 205 struct hints_bucket *bp; 206 207 /* If not mapped, and we have not tried before, try to map the 208 * hints, if previous attempts failed hheader is -1 and we 209 * do not wish to retry it. 210 */ 211 if (hheader == NULL) 212 _dl_maphints(); 213 214 /* if it failed to map, return failure */ 215 if (!(HINTS_VALID)) 216 return NULL; 217 218 bp = hbuckets + (_dl_hinthash(name, major, minor) % hheader->hh_nbucket); 219 220 while (1) { 221 /* Sanity check */ 222 if (bp->hi_namex >= hheader->hh_strtab_sz) { 223 _dl_printf("Bad name index: %#x\n", bp->hi_namex); 224 _dl_exit(7); 225 break; 226 } 227 if (bp->hi_pathx >= hheader->hh_strtab_sz) { 228 _dl_printf("Bad path index: %#x\n", bp->hi_pathx); 229 _dl_exit(7); 230 break; 231 } 232 233 if (_dl_strcmp(name, hstrtab + bp->hi_namex) == 0) { 234 /* It's `name', check version numbers */ 235 if (bp->hi_major == major && 236 (bp->hi_ndewey < 2 || bp->hi_minor >= minor)) { 237 if (prefered_path == NULL || 238 _dl_strncmp(prefered_path, 239 hstrtab + bp->hi_pathx, 240 _dl_strlen(prefered_path)) == 0) 241 return hstrtab + bp->hi_pathx; 242 } 243 } 244 245 if (bp->hi_next == -1) 246 break; 247 248 /* Move on to next in bucket */ 249 bp = &hbuckets[bp->hi_next]; 250 } 251 252 /* No hints available for name */ 253 return NULL; 254} 255int 256_dl_hinthash(cp, vmajor, vminor) 257 char *cp; 258 int vmajor, vminor; 259{ 260 int k = 0; 261 262 while (*cp) 263 k = (((k << 1) + (k >> 14)) ^ (*cp++)) & 0x3fff; 264 265 k = (((k << 1) + (k >> 14)) ^ (vmajor*257)) & 0x3fff; 266 if (hheader->hh_version == LD_HINTS_VERSION_1) 267 k = (((k << 1) + (k >> 14)) ^ (vminor*167)) & 0x3fff; 268 269 return k; 270} 271