crypto/dso/dso_lib.c

   1 /*
   2  * Copyright 2000-2017 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 DEFINE_STACK_OF(void)
  14
  15 static DSO_METHOD *default_DSO_meth = NULL;
  16
  17 static DSO *DSO_new_method(DSO_METHOD *meth)
  18 {
  19     DSO *ret;
  20
  21     if (default_DSO_meth == NULL) {
  22         /*
  23          * We default to DSO_METH_openssl() which in turn defaults to
  24          * stealing the "best available" method. Will fallback to
  25          * DSO_METH_null() in the worst case.
  26          */
  27         default_DSO_meth = DSO_METHOD_openssl();
  28     }
  29     ret = OPENSSL_zalloc(sizeof(*ret));
  30     if (ret == NULL) {
  31         DSOerr(DSO_F_DSO_NEW_METHOD, ERR_R_MALLOC_FAILURE);
  32         return NULL;
  33     }
  34     ret->meth_data = sk_void_new_null();
  35     if (ret->meth_data == NULL) {
  36         /* sk_new doesn't generate any errors so we do */
  37         DSOerr(DSO_F_DSO_NEW_METHOD, ERR_R_MALLOC_FAILURE);
  38         OPENSSL_free(ret);
  39         return NULL;
  40     }
  41     ret->meth = default_DSO_meth;
  42     ret->references = 1;
  43     ret->lock = CRYPTO_THREAD_lock_new();
  44     if (ret->lock == NULL) {
  45         DSOerr(DSO_F_DSO_NEW_METHOD, ERR_R_MALLOC_FAILURE);
  46         sk_void_free(ret->meth_data);
  47         OPENSSL_free(ret);
  48         return NULL;
  49     }
  50
  51     if ((ret->meth->init != NULL) && !ret->meth->init(ret)) {
  52         DSO_free(ret);
  53         ret = NULL;
  54     }
  55
  56     return ret;
  57 }
  58
  59 DSO *DSO_new(void)
  60 {
  61     return DSO_new_method(NULL);
  62 }
  63
  64 int DSO_free(DSO *dso)
  65 {
  66     int i;
  67
  68     if (dso == NULL)
  69         return 1;
  70
  71     if (CRYPTO_DOWN_REF(&dso->references, &i, dso->lock) <= 0)
  72         return 0;
  73
  74     REF_PRINT_COUNT("DSO", dso);
  75     if (i > 0)
  76         return 1;
  77     REF_ASSERT_ISNT(i < 0);
  78
  79     if ((dso->flags & DSO_FLAG_NO_UNLOAD_ON_FREE) == 0) {
  80         if ((dso->meth->dso_unload != NULL) && !dso->meth->dso_unload(dso)) {
  81             DSOerr(DSO_F_DSO_FREE, DSO_R_UNLOAD_FAILED);
  82             return 0;
  83         }
  84     }
  85
  86     if ((dso->meth->finish != NULL) && !dso->meth->finish(dso)) {
  87         DSOerr(DSO_F_DSO_FREE, DSO_R_FINISH_FAILED);
  88         return 0;
  89     }
  90
  91     sk_void_free(dso->meth_data);
  92     OPENSSL_free(dso->filename);
  93     OPENSSL_free(dso->loaded_filename);
  94     CRYPTO_THREAD_lock_free(dso->lock);
  95     OPENSSL_free(dso);
  96     return 1;
  97 }
  98
  99 int DSO_flags(DSO *dso)
 100 {
 101     return ((dso == NULL) ? 0 : dso->flags);
 102 }
 103
 104 int DSO_up_ref(DSO *dso)
 105 {
 106     int i;
 107
 108     if (dso == NULL) {
 109         DSOerr(DSO_F_DSO_UP_REF, ERR_R_PASSED_NULL_PARAMETER);
 110         return 0;
 111     }
 112
 113     if (CRYPTO_UP_REF(&dso->references, &i, dso->lock) <= 0)
 114         return 0;
 115
 116     REF_PRINT_COUNT("DSO", dso);
 117     REF_ASSERT_ISNT(i < 2);
 118     return ((i > 1) ? 1 : 0);
 119 }
 120
 121 DSO *DSO_load(DSO *dso, const char *filename, DSO_METHOD *meth, int flags)
 122 {
 123     DSO *ret;
 124     int allocated = 0;
 125
 126     if (dso == NULL) {
 127         ret = DSO_new_method(meth);
 128         if (ret == NULL) {
 129             DSOerr(DSO_F_DSO_LOAD, ERR_R_MALLOC_FAILURE);
 130             goto err;
 131         }
 132         allocated = 1;
 133         /* Pass the provided flags to the new DSO object */
 134         if (DSO_ctrl(ret, DSO_CTRL_SET_FLAGS, flags, NULL) < 0) {
 135             DSOerr(DSO_F_DSO_LOAD, DSO_R_CTRL_FAILED);
 136             goto err;
 137         }
 138     } else
 139         ret = dso;
 140     /* Don't load if we're currently already loaded */
 141     if (ret->filename != NULL) {
 142         DSOerr(DSO_F_DSO_LOAD, DSO_R_DSO_ALREADY_LOADED);
 143         goto err;
 144     }
 145     /*
 146      * filename can only be NULL if we were passed a dso that already has one
 147      * set.
 148      */
 149     if (filename != NULL)
 150         if (!DSO_set_filename(ret, filename)) {
 151             DSOerr(DSO_F_DSO_LOAD, DSO_R_SET_FILENAME_FAILED);
 152             goto err;
 153         }
 154     filename = ret->filename;
 155     if (filename == NULL) {
 156         DSOerr(DSO_F_DSO_LOAD, DSO_R_NO_FILENAME);
 157         goto err;
 158     }
 159     if (ret->meth->dso_load == NULL) {
 160         DSOerr(DSO_F_DSO_LOAD, DSO_R_UNSUPPORTED);
 161         goto err;
 162     }
 163     if (!ret->meth->dso_load(ret)) {
 164         DSOerr(DSO_F_DSO_LOAD, DSO_R_LOAD_FAILED);
 165         goto err;
 166     }
 167     /* Load succeeded */
 168     return ret;
 169  err:
 170     if (allocated)
 171         DSO_free(ret);
 172     return NULL;
 173 }
 174
 175 DSO_FUNC_TYPE DSO_bind_func(DSO *dso, const char *symname)
 176 {
 177     DSO_FUNC_TYPE ret = NULL;
 178
 179     if ((dso == NULL) || (symname == NULL)) {
 180         DSOerr(DSO_F_DSO_BIND_FUNC, ERR_R_PASSED_NULL_PARAMETER);
 181         return NULL;
 182     }
 183     if (dso->meth->dso_bind_func == NULL) {
 184         DSOerr(DSO_F_DSO_BIND_FUNC, DSO_R_UNSUPPORTED);
 185         return NULL;
 186     }
 187     if ((ret = dso->meth->dso_bind_func(dso, symname)) == NULL) {
 188         DSOerr(DSO_F_DSO_BIND_FUNC, DSO_R_SYM_FAILURE);
 189         return NULL;
 190     }
 191     /* Success */
 192     return ret;
 193 }
 194
 195 /*
 196  * I don't really like these *_ctrl functions very much to be perfectly
 197  * honest. For one thing, I think I have to return a negative value for any
 198  * error because possible DSO_ctrl() commands may return values such as
 199  * "size"s that can legitimately be zero (making the standard
 200  * "if (DSO_cmd(...))" form that works almost everywhere else fail at odd
 201  * times. I'd prefer "output" values to be passed by reference and the return
 202  * value as success/failure like usual ... but we conform when we must... :-)
 203  */
 204 long DSO_ctrl(DSO *dso, int cmd, long larg, void *parg)
 205 {
 206     if (dso == NULL) {
 207         DSOerr(DSO_F_DSO_CTRL, ERR_R_PASSED_NULL_PARAMETER);
 208         return -1;
 209     }
 210     /*
 211      * We should intercept certain generic commands and only pass control to
 212      * the method-specific ctrl() function if it's something we don't handle.
 213      */
 214     switch (cmd) {
 215     case DSO_CTRL_GET_FLAGS:
 216         return dso->flags;
 217     case DSO_CTRL_SET_FLAGS:
 218         dso->flags = (int)larg;
 219         return 0;
 220     case DSO_CTRL_OR_FLAGS:
 221         dso->flags |= (int)larg;
 222         return 0;
 223     default:
 224         break;
 225     }
 226     if ((dso->meth == NULL) || (dso->meth->dso_ctrl == NULL)) {
 227         DSOerr(DSO_F_DSO_CTRL, DSO_R_UNSUPPORTED);
 228         return -1;
 229     }
 230     return dso->meth->dso_ctrl(dso, cmd, larg, parg);
 231 }
 232
 233 const char *DSO_get_filename(DSO *dso)
 234 {
 235     if (dso == NULL) {
 236         DSOerr(DSO_F_DSO_GET_FILENAME, ERR_R_PASSED_NULL_PARAMETER);
 237         return NULL;
 238     }
 239     return dso->filename;
 240 }
 241
 242 int DSO_set_filename(DSO *dso, const char *filename)
 243 {
 244     char *copied;
 245
 246     if ((dso == NULL) || (filename == NULL)) {
 247         DSOerr(DSO_F_DSO_SET_FILENAME, ERR_R_PASSED_NULL_PARAMETER);
 248         return 0;
 249     }
 250     if (dso->loaded_filename) {
 251         DSOerr(DSO_F_DSO_SET_FILENAME, DSO_R_DSO_ALREADY_LOADED);
 252         return 0;
 253     }
 254     /* We'll duplicate filename */
 255     copied = OPENSSL_strdup(filename);
 256     if (copied == NULL) {
 257         DSOerr(DSO_F_DSO_SET_FILENAME, ERR_R_MALLOC_FAILURE);
 258         return 0;
 259     }
 260     OPENSSL_free(dso->filename);
 261     dso->filename = copied;
 262     return 1;
 263 }
 264
 265 char *DSO_merge(DSO *dso, const char *filespec1, const char *filespec2)
 266 {
 267     char *result = NULL;
 268
 269     if (dso == NULL || filespec1 == NULL) {
 270         DSOerr(DSO_F_DSO_MERGE, ERR_R_PASSED_NULL_PARAMETER);
 271         return NULL;
 272     }
 273     if ((dso->flags & DSO_FLAG_NO_NAME_TRANSLATION) == 0) {
 274         if (dso->merger != NULL)
 275             result = dso->merger(dso, filespec1, filespec2);
 276         else if (dso->meth->dso_merger != NULL)
 277             result = dso->meth->dso_merger(dso, filespec1, filespec2);
 278     }
 279     return result;
 280 }
 281
 282 char *DSO_convert_filename(DSO *dso, const char *filename)
 283 {
 284     char *result = NULL;
 285
 286     if (dso == NULL) {
 287         DSOerr(DSO_F_DSO_CONVERT_FILENAME, ERR_R_PASSED_NULL_PARAMETER);
 288         return NULL;
 289     }
 290     if (filename == NULL)
 291         filename = dso->filename;
 292     if (filename == NULL) {
 293         DSOerr(DSO_F_DSO_CONVERT_FILENAME, DSO_R_NO_FILENAME);
 294         return NULL;
 295     }
 296     if ((dso->flags & DSO_FLAG_NO_NAME_TRANSLATION) == 0) {
 297         if (dso->name_converter != NULL)
 298             result = dso->name_converter(dso, filename);
 299         else if (dso->meth->dso_name_converter != NULL)
 300             result = dso->meth->dso_name_converter(dso, filename);
 301     }
 302     if (result == NULL) {
 303         result = OPENSSL_strdup(filename);
 304         if (result == NULL) {
 305             DSOerr(DSO_F_DSO_CONVERT_FILENAME, ERR_R_MALLOC_FAILURE);
 306             return NULL;
 307         }
 308     }
 309     return result;
 310 }
 311
 312 int DSO_pathbyaddr(void *addr, char *path, int sz)
 313 {
 314     DSO_METHOD *meth = default_DSO_meth;
 315     if (meth == NULL)
 316         meth = DSO_METHOD_openssl();
 317     if (meth->pathbyaddr == NULL) {
 318         DSOerr(DSO_F_DSO_PATHBYADDR, DSO_R_UNSUPPORTED);
 319         return -1;
 320     }
 321     return (*meth->pathbyaddr) (addr, path, sz);
 322 }
 323
 324 DSO *DSO_dsobyaddr(void *addr, int flags)
 325 {
 326     DSO *ret = NULL;
 327     char *filename = NULL;
 328     int len = DSO_pathbyaddr(addr, NULL, 0);
 329
 330     if (len < 0)
 331         return NULL;
 332
 333     filename = OPENSSL_malloc(len);
 334     if (filename != NULL
 335             && DSO_pathbyaddr(addr, filename, len) == len)
 336         ret = DSO_load(NULL, filename, NULL, flags);
 337
 338     OPENSSL_free(filename);
 339     return ret;
 340 }
 341
 342 void *DSO_global_lookup(const char *name)
 343 {
 344     DSO_METHOD *meth = default_DSO_meth;
 345     if (meth == NULL)
 346         meth = DSO_METHOD_openssl();
 347     if (meth->globallookup == NULL) {
 348         DSOerr(DSO_F_DSO_GLOBAL_LOOKUP, DSO_R_UNSUPPORTED);
 349         return NULL;
 350     }
 351     return (*meth->globallookup) (name);
 352 }