crypto/dso/dso_dlfcn.c

   1 /* dso_dlfcn.c -*- mode:C; c-file-style: "eay" -*- */
   2 /*
   3  * Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL project
   4  * 2000.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    licensing@OpenSSL.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59
  60 /*
  61  * We need to do this early, because stdio.h includes the header files that
  62  * handle _GNU_SOURCE and other similar macros.  Defining it later is simply
  63  * too late, because those headers are protected from re- inclusion.
  64  */
  65 #ifndef _GNU_SOURCE
  66 # define _GNU_SOURCE            /* make sure dladdr is declared */
  67 #endif
  68
  69 #include <stdio.h>
  70 #include "internal/cryptlib.h"
  71 #include <openssl/dso.h>
  72
  73 #ifndef DSO_DLFCN
  74 DSO_METHOD *DSO_METHOD_dlfcn(void)
  75 {
  76     return NULL;
  77 }
  78 #else
  79
  80 # ifdef HAVE_DLFCN_H
  81 #  ifdef __osf__
  82 #   define __EXTENSIONS__
  83 #  endif
  84 #  include <dlfcn.h>
  85 #  define HAVE_DLINFO 1
  86 #  if defined(_AIX) || defined(__CYGWIN__) || \
  87      defined(__SCO_VERSION__) || defined(_SCO_ELF) || \
  88      (defined(__osf__) && !defined(RTLD_NEXT))     || \
  89      (defined(__OpenBSD__) && !defined(RTLD_SELF)) || \
  90         defined(__ANDROID__)
  91 #   undef HAVE_DLINFO
  92 #  endif
  93 # endif
  94
  95 /* Part of the hack in "dlfcn_load" ... */
  96 # define DSO_MAX_TRANSLATED_SIZE 256
  97
  98 static int dlfcn_load(DSO *dso);
  99 static int dlfcn_unload(DSO *dso);
 100 static void *dlfcn_bind_var(DSO *dso, const char *symname);
 101 static DSO_FUNC_TYPE dlfcn_bind_func(DSO *dso, const char *symname);
 102 static char *dlfcn_name_converter(DSO *dso, const char *filename);
 103 static char *dlfcn_merger(DSO *dso, const char *filespec1,
 104                           const char *filespec2);
 105 static int dlfcn_pathbyaddr(void *addr, char *path, int sz);
 106 static void *dlfcn_globallookup(const char *name);
 107
 108 static DSO_METHOD dso_meth_dlfcn = {
 109     "OpenSSL 'dlfcn' shared library method",
 110     dlfcn_load,
 111     dlfcn_unload,
 112     dlfcn_bind_var,
 113     dlfcn_bind_func,
 114     NULL,                       /* ctrl */
 115     dlfcn_name_converter,
 116     dlfcn_merger,
 117     NULL,                       /* init */
 118     NULL,                       /* finish */
 119     dlfcn_pathbyaddr,
 120     dlfcn_globallookup
 121 };
 122
 123 DSO_METHOD *DSO_METHOD_dlfcn(void)
 124 {
 125     return (&dso_meth_dlfcn);
 126 }
 127
 128 /*
 129  * Prior to using the dlopen() function, we should decide on the flag we
 130  * send. There's a few different ways of doing this and it's a messy
 131  * venn-diagram to match up which platforms support what. So as we don't have
 132  * autoconf yet, I'm implementing a hack that could be hacked further
 133  * relatively easily to deal with cases as we find them. Initially this is to
 134  * cope with OpenBSD.
 135  */
 136 # if defined(__OpenBSD__) || defined(__NetBSD__)
 137 #  ifdef DL_LAZY
 138 #   define DLOPEN_FLAG DL_LAZY
 139 #  else
 140 #   ifdef RTLD_NOW
 141 #    define DLOPEN_FLAG RTLD_NOW
 142 #   else
 143 #    define DLOPEN_FLAG 0
 144 #   endif
 145 #  endif
 146 # else
 147 #  define DLOPEN_FLAG RTLD_NOW  /* Hope this works everywhere else */
 148 # endif
 149
 150 /*
 151  * For this DSO_METHOD, our meth_data STACK will contain; (i) the handle
 152  * (void*) returned from dlopen().
 153  */
 154
 155 static int dlfcn_load(DSO *dso)
 156 {
 157     void *ptr = NULL;
 158     /* See applicable comments in dso_dl.c */
 159     char *filename = DSO_convert_filename(dso, NULL);
 160     int flags = DLOPEN_FLAG;
 161
 162     if (filename == NULL) {
 163         DSOerr(DSO_F_DLFCN_LOAD, DSO_R_NO_FILENAME);
 164         goto err;
 165     }
 166 # ifdef RTLD_GLOBAL
 167     if (dso->flags & DSO_FLAG_GLOBAL_SYMBOLS)
 168         flags |= RTLD_GLOBAL;
 169 # endif
 170     ptr = dlopen(filename, flags);
 171     if (ptr == NULL) {
 172         DSOerr(DSO_F_DLFCN_LOAD, DSO_R_LOAD_FAILED);
 173         ERR_add_error_data(4, "filename(", filename, "): ", dlerror());
 174         goto err;
 175     }
 176     if (!sk_void_push(dso->meth_data, (char *)ptr)) {
 177         DSOerr(DSO_F_DLFCN_LOAD, DSO_R_STACK_ERROR);
 178         goto err;
 179     }
 180     /* Success */
 181     dso->loaded_filename = filename;
 182     return (1);
 183  err:
 184     /* Cleanup! */
 185     OPENSSL_free(filename);
 186     if (ptr != NULL)
 187         dlclose(ptr);
 188     return (0);
 189 }
 190
 191 static int dlfcn_unload(DSO *dso)
 192 {
 193     void *ptr;
 194     if (dso == NULL) {
 195         DSOerr(DSO_F_DLFCN_UNLOAD, ERR_R_PASSED_NULL_PARAMETER);
 196         return (0);
 197     }
 198     if (sk_void_num(dso->meth_data) < 1)
 199         return (1);
 200     ptr = sk_void_pop(dso->meth_data);
 201     if (ptr == NULL) {
 202         DSOerr(DSO_F_DLFCN_UNLOAD, DSO_R_NULL_HANDLE);
 203         /*
 204          * Should push the value back onto the stack in case of a retry.
 205          */
 206         sk_void_push(dso->meth_data, ptr);
 207         return (0);
 208     }
 209     /* For now I'm not aware of any errors associated with dlclose() */
 210     dlclose(ptr);
 211     return (1);
 212 }
 213
 214 static void *dlfcn_bind_var(DSO *dso, const char *symname)
 215 {
 216     void *ptr, *sym;
 217
 218     if ((dso == NULL) || (symname == NULL)) {
 219         DSOerr(DSO_F_DLFCN_BIND_VAR, ERR_R_PASSED_NULL_PARAMETER);
 220         return (NULL);
 221     }
 222     if (sk_void_num(dso->meth_data) < 1) {
 223         DSOerr(DSO_F_DLFCN_BIND_VAR, DSO_R_STACK_ERROR);
 224         return (NULL);
 225     }
 226     ptr = sk_void_value(dso->meth_data, sk_void_num(dso->meth_data) - 1);
 227     if (ptr == NULL) {
 228         DSOerr(DSO_F_DLFCN_BIND_VAR, DSO_R_NULL_HANDLE);
 229         return (NULL);
 230     }
 231     sym = dlsym(ptr, symname);
 232     if (sym == NULL) {
 233         DSOerr(DSO_F_DLFCN_BIND_VAR, DSO_R_SYM_FAILURE);
 234         ERR_add_error_data(4, "symname(", symname, "): ", dlerror());
 235         return (NULL);
 236     }
 237     return (sym);
 238 }
 239
 240 static DSO_FUNC_TYPE dlfcn_bind_func(DSO *dso, const char *symname)
 241 {
 242     void *ptr;
 243     union {
 244         DSO_FUNC_TYPE sym;
 245         void *dlret;
 246     } u;
 247
 248     if ((dso == NULL) || (symname == NULL)) {
 249         DSOerr(DSO_F_DLFCN_BIND_FUNC, ERR_R_PASSED_NULL_PARAMETER);
 250         return (NULL);
 251     }
 252     if (sk_void_num(dso->meth_data) < 1) {
 253         DSOerr(DSO_F_DLFCN_BIND_FUNC, DSO_R_STACK_ERROR);
 254         return (NULL);
 255     }
 256     ptr = sk_void_value(dso->meth_data, sk_void_num(dso->meth_data) - 1);
 257     if (ptr == NULL) {
 258         DSOerr(DSO_F_DLFCN_BIND_FUNC, DSO_R_NULL_HANDLE);
 259         return (NULL);
 260     }
 261     u.dlret = dlsym(ptr, symname);
 262     if (u.dlret == NULL) {
 263         DSOerr(DSO_F_DLFCN_BIND_FUNC, DSO_R_SYM_FAILURE);
 264         ERR_add_error_data(4, "symname(", symname, "): ", dlerror());
 265         return (NULL);
 266     }
 267     return u.sym;
 268 }
 269
 270 static char *dlfcn_merger(DSO *dso, const char *filespec1,
 271                           const char *filespec2)
 272 {
 273     char *merged;
 274
 275     if (!filespec1 && !filespec2) {
 276         DSOerr(DSO_F_DLFCN_MERGER, ERR_R_PASSED_NULL_PARAMETER);
 277         return (NULL);
 278     }
 279     /*
 280      * If the first file specification is a rooted path, it rules. same goes
 281      * if the second file specification is missing.
 282      */
 283     if (!filespec2 || (filespec1 != NULL && filespec1[0] == '/')) {
 284         merged = OPENSSL_malloc(strlen(filespec1) + 1);
 285         if (!merged) {
 286             DSOerr(DSO_F_DLFCN_MERGER, ERR_R_MALLOC_FAILURE);
 287             return (NULL);
 288         }
 289         strcpy(merged, filespec1);
 290     }
 291     /*
 292      * If the first file specification is missing, the second one rules.
 293      */
 294     else if (!filespec1) {
 295         merged = OPENSSL_malloc(strlen(filespec2) + 1);
 296         if (!merged) {
 297             DSOerr(DSO_F_DLFCN_MERGER, ERR_R_MALLOC_FAILURE);
 298             return (NULL);
 299         }
 300         strcpy(merged, filespec2);
 301     } else {
 302         /*
 303          * This part isn't as trivial as it looks.  It assumes that the
 304          * second file specification really is a directory, and makes no
 305          * checks whatsoever.  Therefore, the result becomes the
 306          * concatenation of filespec2 followed by a slash followed by
 307          * filespec1.
 308          */
 309         int spec2len, len;
 310
 311         spec2len = strlen(filespec2);
 312         len = spec2len + strlen(filespec1);
 313
 314         if (spec2len && filespec2[spec2len - 1] == '/') {
 315             spec2len--;
 316             len--;
 317         }
 318         merged = OPENSSL_malloc(len + 2);
 319         if (!merged) {
 320             DSOerr(DSO_F_DLFCN_MERGER, ERR_R_MALLOC_FAILURE);
 321             return (NULL);
 322         }
 323         strcpy(merged, filespec2);
 324         merged[spec2len] = '/';
 325         strcpy(&merged[spec2len + 1], filespec1);
 326     }
 327     return (merged);
 328 }
 329
 330 # ifdef OPENSSL_SYS_MACOSX
 331 #  define DSO_ext ".dylib"
 332 #  define DSO_extlen 6
 333 # else
 334 #  define DSO_ext ".so"
 335 #  define DSO_extlen 3
 336 # endif
 337
 338 static char *dlfcn_name_converter(DSO *dso, const char *filename)
 339 {
 340     char *translated;
 341     int len, rsize, transform;
 342
 343     len = strlen(filename);
 344     rsize = len + 1;
 345     transform = (strstr(filename, "/") == NULL);
 346     if (transform) {
 347         /* We will convert this to "%s.so" or "lib%s.so" etc */
 348         rsize += DSO_extlen;    /* The length of ".so" */
 349         if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
 350             rsize += 3;         /* The length of "lib" */
 351     }
 352     translated = OPENSSL_malloc(rsize);
 353     if (translated == NULL) {
 354         DSOerr(DSO_F_DLFCN_NAME_CONVERTER, DSO_R_NAME_TRANSLATION_FAILED);
 355         return (NULL);
 356     }
 357     if (transform) {
 358         if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
 359             sprintf(translated, "lib%s" DSO_ext, filename);
 360         else
 361             sprintf(translated, "%s" DSO_ext, filename);
 362     } else
 363         sprintf(translated, "%s", filename);
 364     return (translated);
 365 }
 366
 367 # ifdef __sgi
 368 /*-
 369 This is a quote from IRIX manual for dladdr(3c):
 370
 371      <dlfcn.h> does not contain a prototype for dladdr or definition of
 372      Dl_info.  The #include <dlfcn.h>  in the SYNOPSIS line is traditional,
 373      but contains no dladdr prototype and no IRIX library contains an
 374      implementation.  Write your own declaration based on the code below.
 375
 376      The following code is dependent on internal interfaces that are not
 377      part of the IRIX compatibility guarantee; however, there is no future
 378      intention to change this interface, so on a practical level, the code
 379      below is safe to use on IRIX.
 380 */
 381 #  include <rld_interface.h>
 382 #  ifndef _RLD_INTERFACE_DLFCN_H_DLADDR
 383 #   define _RLD_INTERFACE_DLFCN_H_DLADDR
 384 typedef struct Dl_info {
 385     const char *dli_fname;
 386     void *dli_fbase;
 387     const char *dli_sname;
 388     void *dli_saddr;
 389     int dli_version;
 390     int dli_reserved1;
 391     long dli_reserved[4];
 392 } Dl_info;
 393 #  else
 394 typedef struct Dl_info Dl_info;
 395 #  endif
 396 #  define _RLD_DLADDR             14
 397
 398 static int dladdr(void *address, Dl_info *dl)
 399 {
 400     void *v;
 401     v = _rld_new_interface(_RLD_DLADDR, address, dl);
 402     return (int)v;
 403 }
 404 # endif                         /* __sgi */
 405
 406 static int dlfcn_pathbyaddr(void *addr, char *path, int sz)
 407 {
 408 # ifdef HAVE_DLINFO
 409     Dl_info dli;
 410     int len;
 411
 412     if (addr == NULL) {
 413         union {
 414             int (*f) (void *, char *, int);
 415             void *p;
 416         } t = {
 417             dlfcn_pathbyaddr
 418         };
 419         addr = t.p;
 420     }
 421
 422     if (dladdr(addr, &dli)) {
 423         len = (int)strlen(dli.dli_fname);
 424         if (sz <= 0)
 425             return len + 1;
 426         if (len >= sz)
 427             len = sz - 1;
 428         memcpy(path, dli.dli_fname, len);
 429         path[len++] = 0;
 430         return len;
 431     }
 432
 433     ERR_add_error_data(2, "dlfcn_pathbyaddr(): ", dlerror());
 434 # endif
 435     return -1;
 436 }
 437
 438 static void *dlfcn_globallookup(const char *name)
 439 {
 440     void *ret = NULL, *handle = dlopen(NULL, RTLD_LAZY);
 441
 442     if (handle) {
 443         ret = dlsym(handle, name);
 444         dlclose(handle);
 445     }
 446
 447     return ret;
 448 }
 449 #endif                          /* DSO_DLFCN */