crypto/core_fetch.c

   1 /*
   2  * Copyright 2019 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 <stddef.h>
  11
  12 #include <openssl/core.h>
  13 #include "internal/cryptlib.h"
  14 #include "internal/core.h"
  15 #include "internal/property.h"
  16 #include "internal/provider.h"
  17
  18 struct construct_data_st {
  19     OPENSSL_CTX *libctx;
  20     OSSL_METHOD_STORE *store;
  21     int operation_id;
  22     int force_store;
  23     OSSL_METHOD_CONSTRUCT_METHOD *mcm;
  24     void *mcm_data;
  25 };
  26
  27 static int ossl_method_construct_this(OSSL_PROVIDER *provider, void *cbdata)
  28 {
  29     struct construct_data_st *data = cbdata;
  30     int no_store = 0;    /* Assume caching is ok */
  31     const OSSL_ALGORITHM *map =
  32         ossl_provider_query_operation(provider, data->operation_id, &no_store);
  33
  34     while (map->algorithm_name != NULL) {
  35         const OSSL_ALGORITHM *thismap = map++;
  36         void *method = NULL;
  37
  38         if ((method = data->mcm->construct(thismap->algorithm_name,
  39                                            thismap->implementation, provider,
  40                                            data->mcm_data)) == NULL)
  41             continue;
  42
  43         /*
  44          * Note regarding putting the method in stores:
  45          *
  46          * we don't need to care if it actually got in or not here.
  47          * If it didn't get in, it will simply not be available when
  48          * ossl_method_construct() tries to get it from the store.
  49          *
  50          * It is *expected* that the put function increments the refcnt
  51          * of the passed method.
  52          */
  53
  54         if (data->force_store || !no_store) {
  55             /*
  56              * If we haven't been told not to store,
  57              * add to the global store
  58              */
  59             data->mcm->put(data->libctx, NULL,
  60                            thismap->property_definition,
  61                            method, data->mcm_data);
  62         }
  63
  64         data->mcm->put(data->libctx, data->store,
  65                        thismap->property_definition,
  66                        method, data->mcm_data);
  67
  68         /* refcnt-- because we're dropping the reference */
  69         data->mcm->destruct(method, data->mcm_data);
  70     }
  71
  72     return 1;
  73 }
  74
  75 void *ossl_method_construct(OPENSSL_CTX *libctx, int operation_id,
  76                             const char *name, const char *propquery,
  77                             int force_store,
  78                             OSSL_METHOD_CONSTRUCT_METHOD *mcm, void *mcm_data)
  79 {
  80     void *method = NULL;
  81
  82     if ((method = mcm->get(libctx, NULL, propquery, mcm_data)) == NULL) {
  83         struct construct_data_st cbdata;
  84
  85         /*
  86          * We have a temporary store to be able to easily search among new
  87          * items, or items that should find themselves in the global store.
  88          */
  89         if ((cbdata.store = mcm->alloc_tmp_store()) == NULL)
  90             goto fin;
  91
  92         cbdata.libctx = libctx;
  93         cbdata.operation_id = operation_id;
  94         cbdata.force_store = force_store;
  95         cbdata.mcm = mcm;
  96         cbdata.mcm_data = mcm_data;
  97         ossl_provider_forall_loaded(libctx, ossl_method_construct_this,
  98                                     &cbdata);
  99
 100         method = mcm->get(libctx, cbdata.store, propquery, mcm_data);
 101         mcm->dealloc_tmp_store(cbdata.store);
 102     }
 103
 104  fin:
 105     return method;
 106 }