crypto/dso/dso_lib.c

   1 /*
   2  * Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include "dso_local.h"
  11 #include "internal/refcount.h"
  12
  13 static DSO_METHOD *default_DSO_meth = NULL;
  14
  15 static DSO *DSO_new_method(DSO_METHOD *meth)
  16 {
  17     DSO *ret;
  18
  19     if (default_DSO_meth == NULL) {
  20         /*
  21          * We default to DSO_METH_openssl() which in turn defaults to
  22          * stealing the "best available" method. Will fallback to
  23          * DSO_METH_null() in the worst case.
  24          */
  25         default_DSO_meth = DSO_METHOD_openssl();
  26     }
  27     ret = OPENSSL_zalloc(sizeof(*ret));
  28     if (ret == NULL) {
  29         DSOerr(DSO_F_DSO_NEW_METHOD, ERR_R_MALLOC_FAILURE);
  30         return NULL;
  31     }
  32     ret->meth_data = sk_void_new_null();
  33     if (ret->meth_data == NULL) {
  34         /* sk_new doesn't generate any errors so we do */
  35         DSOerr(DSO_F_DSO_NEW_METHOD, ERR_R_MALLOC_FAILURE);
  36         OPENSSL_free(ret);
  37         return NULL;
  38     }
  39     ret->meth = default_DSO_meth;
  40     ret->references = 1;
  41     ret->lock = CRYPTO_THREAD_lock_new();
  42     if (ret->lock == NULL) {
  43         DSOerr(DSO_F_DSO_NEW_METHOD, ERR_R_MALLOC_FAILURE);
  44         sk_void_free(ret->meth_data);
  45         OPENSSL_free(ret);
  46         return NULL;
  47     }
  48
  49     if ((ret->meth->init != NULL) && !ret->meth->init(ret)) {
  50         DSO_free(ret);
  51         ret = NULL;
  52     }
  53
  54     return ret;
  55 }
  56
  57 DSO *DSO_new(void)
  58 {
  59     return DSO_new_method(NULL);
  60 }
  61
  62 int DSO_free(DSO *dso)
  63 {
  64     int i;
  65
  66     if (dso == NULL)
  67         return 1;
  68
  69     if (CRYPTO_DOWN_REF(&dso->references, &i, dso->lock) <= 0)
  70         return 0;
  71
  72     REF_PRINT_COUNT("DSO", dso);
  73     if (i > 0)
  74         return 1;
  75     REF_ASSERT_ISNT(i < 0);
  76
  77     if ((dso->flags & DSO_FLAG_NO_UNLOAD_ON_FREE) == 0) {
  78         if ((dso->meth->dso_unload != NULL) && !dso->meth->dso_unload(dso)) {
  79             DSOerr(DSO_F_DSO_FREE, DSO_R_UNLOAD_FAILED);
  80             return 0;
  81         }
  82     }
  83
  84     if ((dso->meth->finish != NULL) && !dso->meth->finish(dso)) {
  85         DSOerr(DSO_F_DSO_FREE, DSO_R_FINISH_FAILED);
  86         return 0;
  87     }
  88
  89     sk_void_free(dso->meth_data);
  90     OPENSSL_free(dso->filename);
  91     OPENSSL_free(dso->loaded_filename);
  92     CRYPTO_THREAD_lock_free(dso->lock);
  93     OPENSSL_free(dso);
  94     return 1;
  95 }
  96
  97 int DSO_flags(DSO *dso)
  98 {
  99     return ((dso == NULL) ? 0 : dso->flags);
 100 }
 101
 102 int DSO_up_ref(DSO *dso)
 103 {
 104     int i;
 105
 106     if (dso == NULL) {
 107         DSOerr(DSO_F_DSO_UP_REF, ERR_R_PASSED_NULL_PARAMETER);
 108         return 0;
 109     }
 110
 111     if (CRYPTO_UP_REF(&dso->references, &i, dso->lock) <= 0)
 112         return 0;
 113
 114     REF_PRINT_COUNT("DSO", dso);
 115     REF_ASSERT_ISNT(i < 2);
 116     return ((i > 1) ? 1 : 0);
 117 }
 118
 119 DSO *DSO_load(DSO *dso, const char *filename, DSO_METHOD *meth, int flags)
 120 {
 121     DSO *ret;
 122     int allocated = 0;
 123
 124     if (dso == NULL) {
 125         ret = DSO_new_method(meth);
 126         if (ret == NULL) {
 127             DSOerr(DSO_F_DSO_LOAD, ERR_R_MALLOC_FAILURE);
 128             goto err;
 129         }
 130         allocated = 1;
 131         /* Pass the provided flags to the new DSO object */
 132         if (DSO_ctrl(ret, DSO_CTRL_SET_FLAGS, flags, NULL) < 0) {
 133             DSOerr(DSO_F_DSO_LOAD, DSO_R_CTRL_FAILED);
 134             goto err;
 135         }
 136     } else
 137         ret = dso;
 138     /* Don't load if we're currently already loaded */
 139     if (ret->filename != NULL) {
 140         DSOerr(DSO_F_DSO_LOAD, DSO_R_DSO_ALREADY_LOADED);
 141         goto err;
 142     }
 143     /*
 144      * filename can only be NULL if we were passed a dso that already has one
 145      * set.
 146      */
 147     if (filename != NULL)
 148         if (!DSO_set_filename(ret, filename)) {
 149             DSOerr(DSO_F_DSO_LOAD, DSO_R_SET_FILENAME_FAILED);
 150             goto err;
 151         }
 152     filename = ret->filename;
 153     if (filename == NULL) {
 154         DSOerr(DSO_F_DSO_LOAD, DSO_R_NO_FILENAME);
 155         goto err;
 156     }
 157     if (ret->meth->dso_load == NULL) {
 158         DSOerr(DSO_F_DSO_LOAD, DSO_R_UNSUPPORTED);
 159         goto err;
 160     }
 161     if (!ret->meth->dso_load(ret)) {
 162         DSOerr(DSO_F_DSO_LOAD, DSO_R_LOAD_FAILED);
 163         goto err;
 164     }
 165     /* Load succeeded */
 166     return ret;
 167  err:
 168     if (allocated)
 169         DSO_free(ret);
 170     return NULL;
 171 }
 172
 173 DSO_FUNC_TYPE DSO_bind_func(DSO *dso, const char *symname)
 174 {
 175     DSO_FUNC_TYPE ret = NULL;
 176
 177     if ((dso == NULL) || (symname == NULL)) {
 178         DSOerr(DSO_F_DSO_BIND_FUNC, ERR_R_PASSED_NULL_PARAMETER);
 179         return NULL;
 180     }
 181     if (dso->meth->dso_bind_func == NULL) {
 182         DSOerr(DSO_F_DSO_BIND_FUNC, DSO_R_UNSUPPORTED);
 183         return NULL;
 184     }
 185     if ((ret = dso->meth->dso_bind_func(dso, symname)) == NULL) {
 186         DSOerr(DSO_F_DSO_BIND_FUNC, DSO_R_SYM_FAILURE);
 187         return NULL;
 188     }
 189     /* Success */
 190     return ret;
 191 }
 192
 193 /*
 194  * I don't really like these *_ctrl functions very much to be perfectly
 195  * honest. For one thing, I think I have to return a negative value for any
 196  * error because possible DSO_ctrl() commands may return values such as
 197  * "size"s that can legitimately be zero (making the standard
 198  * "if (DSO_cmd(...))" form that works almost everywhere else fail at odd
 199  * times. I'd prefer "output" values to be passed by reference and the return
 200  * value as success/failure like usual ... but we conform when we must... :-)
 201  */
 202 long DSO_ctrl(DSO *dso, int cmd, long larg, void *parg)
 203 {
 204     if (dso == NULL) {
 205         DSOerr(DSO_F_DSO_CTRL, ERR_R_PASSED_NULL_PARAMETER);
 206         return -1;
 207     }
 208     /*
 209      * We should intercept certain generic commands and only pass control to
 210      * the method-specific ctrl() function if it's something we don't handle.
 211      */
 212     switch (cmd) {
 213     case DSO_CTRL_GET_FLAGS:
 214         return dso->flags;
 215     case DSO_CTRL_SET_FLAGS:
 216         dso->flags = (int)larg;
 217         return 0;
 218     case DSO_CTRL_OR_FLAGS:
 219         dso->flags |= (int)larg;
 220         return 0;
 221     default:
 222         break;
 223     }
 224     if ((dso->meth == NULL) || (dso->meth->dso_ctrl == NULL)) {
 225         DSOerr(DSO_F_DSO_CTRL, DSO_R_UNSUPPORTED);
 226         return -1;
 227     }
 228     return dso->meth->dso_ctrl(dso, cmd, larg, parg);
 229 }
 230
 231 const char *DSO_get_filename(DSO *dso)
 232 {
 233     if (dso == NULL) {
 234         DSOerr(DSO_F_DSO_GET_FILENAME, ERR_R_PASSED_NULL_PARAMETER);
 235         return NULL;
 236     }
 237     return dso->filename;
 238 }
 239
 240 int DSO_set_filename(DSO *dso, const char *filename)
 241 {
 242     char *copied;
 243
 244     if ((dso == NULL) || (filename == NULL)) {
 245         DSOerr(DSO_F_DSO_SET_FILENAME, ERR_R_PASSED_NULL_PARAMETER);
 246         return 0;
 247     }
 248     if (dso->loaded_filename) {
 249         DSOerr(DSO_F_DSO_SET_FILENAME, DSO_R_DSO_ALREADY_LOADED);
 250         return 0;
 251     }
 252     /* We'll duplicate filename */
 253     copied = OPENSSL_strdup(filename);
 254     if (copied == NULL) {
 255         DSOerr(DSO_F_DSO_SET_FILENAME, ERR_R_MALLOC_FAILURE);
 256         return 0;
 257     }
 258     OPENSSL_free(dso->filename);
 259     dso->filename = copied;
 260     return 1;
 261 }
 262
 263 char *DSO_merge(DSO *dso, const char *filespec1, const char *filespec2)
 264 {
 265     char *result = NULL;
 266
 267     if (dso == NULL || filespec1 == NULL) {
 268         DSOerr(DSO_F_DSO_MERGE, ERR_R_PASSED_NULL_PARAMETER);
 269         return NULL;
 270     }
 271     if ((dso->flags & DSO_FLAG_NO_NAME_TRANSLATION) == 0) {
 272         if (dso->merger != NULL)
 273             result = dso->merger(dso, filespec1, filespec2);
 274         else if (dso->meth->dso_merger != NULL)
 275             result = dso->meth->dso_merger(dso, filespec1, filespec2);
 276     }
 277     return result;
 278 }
 279
 280 char *DSO_convert_filename(DSO *dso, const char *filename)
 281 {
 282     char *result = NULL;
 283
 284     if (dso == NULL) {
 285         DSOerr(DSO_F_DSO_CONVERT_FILENAME, ERR_R_PASSED_NULL_PARAMETER);
 286         return NULL;
 287     }
 288     if (filename == NULL)
 289         filename = dso->filename;
 290     if (filename == NULL) {
 291         DSOerr(DSO_F_DSO_CONVERT_FILENAME, DSO_R_NO_FILENAME);
 292         return NULL;
 293     }
 294     if ((dso->flags & DSO_FLAG_NO_NAME_TRANSLATION) == 0) {
 295         if (dso->name_converter != NULL)
 296             result = dso->name_converter(dso, filename);
 297         else if (dso->meth->dso_name_converter != NULL)
 298             result = dso->meth->dso_name_converter(dso, filename);
 299     }
 300     if (result == NULL) {
 301         result = OPENSSL_strdup(filename);
 302         if (result == NULL) {
 303             DSOerr(DSO_F_DSO_CONVERT_FILENAME, ERR_R_MALLOC_FAILURE);
 304             return NULL;
 305         }
 306     }
 307     return result;
 308 }
 309
 310 int DSO_pathbyaddr(void *addr, char *path, int sz)
 311 {
 312     DSO_METHOD *meth = default_DSO_meth;
 313     if (meth == NULL)
 314         meth = DSO_METHOD_openssl();
 315     if (meth->pathbyaddr == NULL) {
 316         DSOerr(DSO_F_DSO_PATHBYADDR, DSO_R_UNSUPPORTED);
 317         return -1;
 318     }
 319     return (*meth->pathbyaddr) (addr, path, sz);
 320 }
 321
 322 DSO *DSO_dsobyaddr(void *addr, int flags)
 323 {
 324     DSO *ret = NULL;
 325     char *filename = NULL;
 326     int len = DSO_pathbyaddr(addr, NULL, 0);
 327
 328     if (len < 0)
 329         return NULL;
 330
 331     filename = OPENSSL_malloc(len);
 332     if (filename != NULL
 333             && DSO_pathbyaddr(addr, filename, len) == len)
 334         ret = DSO_load(NULL, filename, NULL, flags);
 335
 336     OPENSSL_free(filename);
 337     return ret;
 338 }
 339
 340 void *DSO_global_lookup(const char *name)
 341 {
 342     DSO_METHOD *meth = default_DSO_meth;
 343     if (meth == NULL)
 344         meth = DSO_METHOD_openssl();
 345     if (meth->globallookup == NULL) {
 346         DSOerr(DSO_F_DSO_GLOBAL_LOOKUP, DSO_R_UNSUPPORTED);
 347         return NULL;
 348     }
 349     return (*meth->globallookup) (name);
 350 }