crypto/context.c

   1 /*
   2  * Copyright 2019-2020 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 "crypto/cryptlib.h"
  11 #include <openssl/conf.h>
  12 #include "internal/thread_once.h"
  13 #include "internal/property.h"
  14
  15 struct openssl_ctx_onfree_list_st {
  16     openssl_ctx_onfree_fn *fn;
  17     struct openssl_ctx_onfree_list_st *next;
  18 };
  19
  20 struct openssl_ctx_st {
  21     CRYPTO_RWLOCK *lock;
  22     CRYPTO_EX_DATA data;
  23
  24     /*
  25      * For most data in the OPENSSL_CTX we just use ex_data to store it. But
  26      * that doesn't work for ex_data itself - so we store that directly.
  27      */
  28     OSSL_EX_DATA_GLOBAL global;
  29
  30     /* Map internal static indexes to dynamically created indexes */
  31     int dyn_indexes[OPENSSL_CTX_MAX_INDEXES];
  32
  33     /* Keep a separate lock for each index */
  34     CRYPTO_RWLOCK *index_locks[OPENSSL_CTX_MAX_INDEXES];
  35
  36     CRYPTO_RWLOCK *oncelock;
  37     int run_once_done[OPENSSL_CTX_MAX_RUN_ONCE];
  38     int run_once_ret[OPENSSL_CTX_MAX_RUN_ONCE];
  39     struct openssl_ctx_onfree_list_st *onfreelist;
  40 };
  41
  42 #ifndef FIPS_MODULE
  43 static OPENSSL_CTX default_context_int;
  44
  45 /* Always points at default_context_int if it has been initialised */
  46 static OPENSSL_CTX *default_context = NULL;
  47 #endif
  48
  49 static int context_init(OPENSSL_CTX *ctx)
  50 {
  51     size_t i;
  52     int exdata_done = 0;
  53
  54     ctx->lock = CRYPTO_THREAD_lock_new();
  55     if (ctx->lock == NULL)
  56         return 0;
  57
  58     ctx->oncelock = CRYPTO_THREAD_lock_new();
  59     if (ctx->oncelock == NULL)
  60         goto err;
  61
  62     for (i = 0; i < OPENSSL_CTX_MAX_INDEXES; i++) {
  63         ctx->index_locks[i] = CRYPTO_THREAD_lock_new();
  64         ctx->dyn_indexes[i] = -1;
  65         if (ctx->index_locks[i] == NULL)
  66             goto err;
  67     }
  68
  69     /* OPENSSL_CTX is built on top of ex_data so we initialise that directly */
  70     if (!do_ex_data_init(ctx))
  71         goto err;
  72     exdata_done = 1;
  73
  74     if (!crypto_new_ex_data_ex(ctx, CRYPTO_EX_INDEX_OPENSSL_CTX, NULL,
  75                                &ctx->data)) {
  76         crypto_cleanup_all_ex_data_int(ctx);
  77         goto err;
  78     }
  79
  80     /* Everything depends on properties, so we also pre-initialise that */
  81     if (!ossl_property_parse_init(ctx))
  82         goto err;
  83
  84     return 1;
  85  err:
  86     if (exdata_done)
  87         crypto_cleanup_all_ex_data_int(ctx);
  88     CRYPTO_THREAD_lock_free(ctx->oncelock);
  89     CRYPTO_THREAD_lock_free(ctx->lock);
  90     ctx->lock = NULL;
  91     return 0;
  92 }
  93
  94 static int context_deinit(OPENSSL_CTX *ctx)
  95 {
  96     struct openssl_ctx_onfree_list_st *tmp, *onfree;
  97     int i;
  98
  99     if (ctx == NULL)
 100         return 1;
 101
 102     ossl_ctx_thread_stop(ctx);
 103
 104     onfree = ctx->onfreelist;
 105     while (onfree != NULL) {
 106         onfree->fn(ctx);
 107         tmp = onfree;
 108         onfree = onfree->next;
 109         OPENSSL_free(tmp);
 110     }
 111     CRYPTO_free_ex_data(CRYPTO_EX_INDEX_OPENSSL_CTX, NULL, &ctx->data);
 112     crypto_cleanup_all_ex_data_int(ctx);
 113     for (i = 0; i < OPENSSL_CTX_MAX_INDEXES; i++)
 114         CRYPTO_THREAD_lock_free(ctx->index_locks[i]);
 115
 116     CRYPTO_THREAD_lock_free(ctx->oncelock);
 117     CRYPTO_THREAD_lock_free(ctx->lock);
 118     ctx->lock = NULL;
 119     return 1;
 120 }
 121
 122 #ifndef FIPS_MODULE
 123 void openssl_ctx_default_deinit(void)
 124 {
 125     context_deinit(default_context);
 126 }
 127
 128 static CRYPTO_ONCE default_context_init = CRYPTO_ONCE_STATIC_INIT;
 129 DEFINE_RUN_ONCE_STATIC(do_default_context_init)
 130 {
 131     if (context_init(&default_context_int))
 132         default_context = &default_context_int;
 133
 134     return 1;
 135 }
 136 #endif
 137
 138 OPENSSL_CTX *OPENSSL_CTX_new(void)
 139 {
 140     OPENSSL_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
 141
 142     if (ctx != NULL && !context_init(ctx)) {
 143         OPENSSL_CTX_free(ctx);
 144         ctx = NULL;
 145     }
 146     return ctx;
 147 }
 148
 149 #ifndef FIPS_MODULE
 150 int OPENSSL_CTX_load_config(OPENSSL_CTX *ctx, const char *config_file)
 151 {
 152     return CONF_modules_load_file_with_libctx(ctx, config_file, NULL, 0) > 0;
 153 }
 154 #endif
 155
 156 void OPENSSL_CTX_free(OPENSSL_CTX *ctx)
 157 {
 158     if (ctx != NULL)
 159         context_deinit(ctx);
 160     OPENSSL_free(ctx);
 161 }
 162
 163 OPENSSL_CTX *openssl_ctx_get_concrete(OPENSSL_CTX *ctx)
 164 {
 165 #ifndef FIPS_MODULE
 166     if (ctx == NULL) {
 167         if (!RUN_ONCE(&default_context_init, do_default_context_init))
 168             return 0;
 169         return default_context;
 170     }
 171 #endif
 172     return ctx;
 173 }
 174
 175 int openssl_ctx_is_default(OPENSSL_CTX *ctx)
 176 {
 177 #ifndef FIPS_MODULE
 178     if (ctx == NULL || ctx == default_context)
 179         return 1;
 180 #endif
 181     return 0;
 182 }
 183
 184 static void openssl_ctx_generic_new(void *parent_ign, void *ptr_ign,
 185                                     CRYPTO_EX_DATA *ad, int index,
 186                                     long argl_ign, void *argp)
 187 {
 188     const OPENSSL_CTX_METHOD *meth = argp;
 189     void *ptr = meth->new_func(crypto_ex_data_get_openssl_ctx(ad));
 190
 191     if (ptr != NULL)
 192         CRYPTO_set_ex_data(ad, index, ptr);
 193 }
 194 static void openssl_ctx_generic_free(void *parent_ign, void *ptr,
 195                                      CRYPTO_EX_DATA *ad, int index,
 196                                      long argl_ign, void *argp)
 197 {
 198     const OPENSSL_CTX_METHOD *meth = argp;
 199
 200     meth->free_func(ptr);
 201 }
 202
 203 /* Non-static so we can use it in context_internal_test */
 204 static int openssl_ctx_init_index(OPENSSL_CTX *ctx, int static_index,
 205                                   const OPENSSL_CTX_METHOD *meth)
 206 {
 207     int idx;
 208
 209     ctx = openssl_ctx_get_concrete(ctx);
 210     if (ctx == NULL)
 211         return 0;
 212
 213     idx = crypto_get_ex_new_index_ex(ctx, CRYPTO_EX_INDEX_OPENSSL_CTX, 0,
 214                                      (void *)meth,
 215                                      openssl_ctx_generic_new,
 216                                      NULL, openssl_ctx_generic_free);
 217     if (idx < 0)
 218         return 0;
 219
 220     ctx->dyn_indexes[static_index] = idx;
 221     return 1;
 222 }
 223
 224 void *openssl_ctx_get_data(OPENSSL_CTX *ctx, int index,
 225                            const OPENSSL_CTX_METHOD *meth)
 226 {
 227     void *data = NULL;
 228     int dynidx;
 229
 230     ctx = openssl_ctx_get_concrete(ctx);
 231     if (ctx == NULL)
 232         return NULL;
 233
 234     CRYPTO_THREAD_read_lock(ctx->lock);
 235     dynidx = ctx->dyn_indexes[index];
 236     CRYPTO_THREAD_unlock(ctx->lock);
 237
 238     if (dynidx != -1) {
 239         CRYPTO_THREAD_read_lock(ctx->index_locks[index]);
 240         data = CRYPTO_get_ex_data(&ctx->data, dynidx);
 241         CRYPTO_THREAD_unlock(ctx->index_locks[index]);
 242         return data;
 243     }
 244
 245     CRYPTO_THREAD_write_lock(ctx->index_locks[index]);
 246     CRYPTO_THREAD_write_lock(ctx->lock);
 247
 248     dynidx = ctx->dyn_indexes[index];
 249     if (dynidx != -1) {
 250         CRYPTO_THREAD_unlock(ctx->lock);
 251         data = CRYPTO_get_ex_data(&ctx->data, dynidx);
 252         CRYPTO_THREAD_unlock(ctx->index_locks[index]);
 253         return data;
 254     }
 255
 256     if (!openssl_ctx_init_index(ctx, index, meth)) {
 257         CRYPTO_THREAD_unlock(ctx->lock);
 258         CRYPTO_THREAD_unlock(ctx->index_locks[index]);
 259         return NULL;
 260     }
 261
 262     CRYPTO_THREAD_unlock(ctx->lock);
 263
 264     /* The alloc call ensures there's a value there */
 265     if (CRYPTO_alloc_ex_data(CRYPTO_EX_INDEX_OPENSSL_CTX, NULL,
 266                              &ctx->data, ctx->dyn_indexes[index]))
 267         data = CRYPTO_get_ex_data(&ctx->data, ctx->dyn_indexes[index]);
 268
 269     CRYPTO_THREAD_unlock(ctx->index_locks[index]);
 270
 271     return data;
 272 }
 273
 274 OSSL_EX_DATA_GLOBAL *openssl_ctx_get_ex_data_global(OPENSSL_CTX *ctx)
 275 {
 276     ctx = openssl_ctx_get_concrete(ctx);
 277     if (ctx == NULL)
 278         return NULL;
 279     return &ctx->global;
 280 }
 281
 282 int openssl_ctx_run_once(OPENSSL_CTX *ctx, unsigned int idx,
 283                          openssl_ctx_run_once_fn run_once_fn)
 284 {
 285     int done = 0, ret = 0;
 286
 287     ctx = openssl_ctx_get_concrete(ctx);
 288     if (ctx == NULL)
 289         return 0;
 290
 291     CRYPTO_THREAD_read_lock(ctx->oncelock);
 292     done = ctx->run_once_done[idx];
 293     if (done)
 294         ret = ctx->run_once_ret[idx];
 295     CRYPTO_THREAD_unlock(ctx->oncelock);
 296
 297     if (done)
 298         return ret;
 299
 300     CRYPTO_THREAD_write_lock(ctx->oncelock);
 301     if (ctx->run_once_done[idx]) {
 302         ret = ctx->run_once_ret[idx];
 303         CRYPTO_THREAD_unlock(ctx->oncelock);
 304         return ret;
 305     }
 306
 307     ret = run_once_fn(ctx);
 308     ctx->run_once_done[idx] = 1;
 309     ctx->run_once_ret[idx] = ret;
 310     CRYPTO_THREAD_unlock(ctx->oncelock);
 311
 312     return ret;
 313 }
 314
 315 int openssl_ctx_onfree(OPENSSL_CTX *ctx, openssl_ctx_onfree_fn onfreefn)
 316 {
 317     struct openssl_ctx_onfree_list_st *newonfree
 318         = OPENSSL_malloc(sizeof(*newonfree));
 319
 320     if (newonfree == NULL)
 321         return 0;
 322
 323     newonfree->fn = onfreefn;
 324     newonfree->next = ctx->onfreelist;
 325     ctx->onfreelist = newonfree;
 326
 327     return 1;
 328 }