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 static int context_init(OPENSSL_CTX *ctx)
  43 {
  44     size_t i;
  45     int exdata_done = 0;
  46
  47     ctx->lock = CRYPTO_THREAD_lock_new();
  48     if (ctx->lock == NULL)
  49         return 0;
  50
  51     ctx->oncelock = CRYPTO_THREAD_lock_new();
  52     if (ctx->oncelock == NULL)
  53         goto err;
  54
  55     for (i = 0; i < OPENSSL_CTX_MAX_INDEXES; i++) {
  56         ctx->index_locks[i] = CRYPTO_THREAD_lock_new();
  57         ctx->dyn_indexes[i] = -1;
  58         if (ctx->index_locks[i] == NULL)
  59             goto err;
  60     }
  61
  62     /* OPENSSL_CTX is built on top of ex_data so we initialise that directly */
  63     if (!do_ex_data_init(ctx))
  64         goto err;
  65     exdata_done = 1;
  66
  67     if (!crypto_new_ex_data_ex(ctx, CRYPTO_EX_INDEX_OPENSSL_CTX, NULL,
  68                                &ctx->data)) {
  69         crypto_cleanup_all_ex_data_int(ctx);
  70         goto err;
  71     }
  72
  73     /* Everything depends on properties, so we also pre-initialise that */
  74     if (!ossl_property_parse_init(ctx))
  75         goto err;
  76
  77     return 1;
  78  err:
  79     if (exdata_done)
  80         crypto_cleanup_all_ex_data_int(ctx);
  81     CRYPTO_THREAD_lock_free(ctx->oncelock);
  82     CRYPTO_THREAD_lock_free(ctx->lock);
  83     ctx->lock = NULL;
  84     return 0;
  85 }
  86
  87 static int context_deinit(OPENSSL_CTX *ctx)
  88 {
  89     struct openssl_ctx_onfree_list_st *tmp, *onfree;
  90     int i;
  91
  92     if (ctx == NULL)
  93         return 1;
  94
  95     ossl_ctx_thread_stop(ctx);
  96
  97     onfree = ctx->onfreelist;
  98     while (onfree != NULL) {
  99         onfree->fn(ctx);
 100         tmp = onfree;
 101         onfree = onfree->next;
 102         OPENSSL_free(tmp);
 103     }
 104     CRYPTO_free_ex_data(CRYPTO_EX_INDEX_OPENSSL_CTX, NULL, &ctx->data);
 105     crypto_cleanup_all_ex_data_int(ctx);
 106     for (i = 0; i < OPENSSL_CTX_MAX_INDEXES; i++)
 107         CRYPTO_THREAD_lock_free(ctx->index_locks[i]);
 108
 109     CRYPTO_THREAD_lock_free(ctx->oncelock);
 110     CRYPTO_THREAD_lock_free(ctx->lock);
 111     ctx->lock = NULL;
 112     return 1;
 113 }
 114
 115 #ifndef FIPS_MODULE
 116 /* The default default context */
 117 static OPENSSL_CTX default_context_int;
 118
 119 static CRYPTO_ONCE default_context_init = CRYPTO_ONCE_STATIC_INIT;
 120 static CRYPTO_THREAD_LOCAL default_context_thread_local;
 121
 122 DEFINE_RUN_ONCE_STATIC(default_context_do_init)
 123 {
 124     return CRYPTO_THREAD_init_local(&default_context_thread_local, NULL)
 125         && context_init(&default_context_int);
 126 }
 127
 128 void openssl_ctx_default_deinit(void)
 129 {
 130     context_deinit(&default_context_int);
 131 }
 132
 133 static OPENSSL_CTX *get_thread_default_context(void)
 134 {
 135     if (!RUN_ONCE(&default_context_init, default_context_do_init))
 136         return NULL;
 137
 138     return CRYPTO_THREAD_get_local(&default_context_thread_local);
 139 }
 140
 141 static OPENSSL_CTX *get_default_context(void)
 142 {
 143     OPENSSL_CTX *current_defctx = get_thread_default_context();
 144
 145     if (current_defctx == NULL)
 146         current_defctx = &default_context_int;
 147     return current_defctx;
 148 }
 149
 150 static int set_default_context(OPENSSL_CTX *defctx)
 151 {
 152     if (defctx == &default_context_int)
 153         defctx = NULL;
 154
 155     return CRYPTO_THREAD_set_local(&default_context_thread_local, defctx);
 156 }
 157 #endif
 158
 159 OPENSSL_CTX *OPENSSL_CTX_new(void)
 160 {
 161     OPENSSL_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
 162
 163     if (ctx != NULL && !context_init(ctx)) {
 164         OPENSSL_CTX_free(ctx);
 165         ctx = NULL;
 166     }
 167     return ctx;
 168 }
 169
 170 #ifndef FIPS_MODULE
 171 int OPENSSL_CTX_load_config(OPENSSL_CTX *ctx, const char *config_file)
 172 {
 173     return CONF_modules_load_file_ex(ctx, config_file, NULL, 0) > 0;
 174 }
 175 #endif
 176
 177 void OPENSSL_CTX_free(OPENSSL_CTX *ctx)
 178 {
 179     if (openssl_ctx_is_default(ctx))
 180         return;
 181
 182     context_deinit(ctx);
 183     OPENSSL_free(ctx);
 184 }
 185
 186 OPENSSL_CTX *OPENSSL_CTX_set0_default(OPENSSL_CTX *libctx)
 187 {
 188 #ifndef FIPS_MODULE
 189     OPENSSL_CTX *current_defctx;
 190
 191     if ((current_defctx = get_default_context()) != NULL
 192         && set_default_context(libctx))
 193         return current_defctx;
 194 #endif
 195
 196     return NULL;
 197 }
 198
 199 OPENSSL_CTX *openssl_ctx_get_concrete(OPENSSL_CTX *ctx)
 200 {
 201 #ifndef FIPS_MODULE
 202     if (ctx == NULL)
 203         return get_default_context();
 204 #endif
 205     return ctx;
 206 }
 207
 208 int openssl_ctx_is_default(OPENSSL_CTX *ctx)
 209 {
 210 #ifndef FIPS_MODULE
 211     if (ctx == NULL || ctx == get_default_context())
 212         return 1;
 213 #endif
 214     return 0;
 215 }
 216
 217 int openssl_ctx_is_global_default(OPENSSL_CTX *ctx)
 218 {
 219 #ifndef FIPS_MODULE
 220     if (openssl_ctx_get_concrete(ctx) == &default_context_int)
 221         return 1;
 222 #endif
 223     return 0;
 224 }
 225
 226 static void openssl_ctx_generic_new(void *parent_ign, void *ptr_ign,
 227                                     CRYPTO_EX_DATA *ad, int index,
 228                                     long argl_ign, void *argp)
 229 {
 230     const OPENSSL_CTX_METHOD *meth = argp;
 231     void *ptr = meth->new_func(crypto_ex_data_get_openssl_ctx(ad));
 232
 233     if (ptr != NULL)
 234         CRYPTO_set_ex_data(ad, index, ptr);
 235 }
 236 static void openssl_ctx_generic_free(void *parent_ign, void *ptr,
 237                                      CRYPTO_EX_DATA *ad, int index,
 238                                      long argl_ign, void *argp)
 239 {
 240     const OPENSSL_CTX_METHOD *meth = argp;
 241
 242     meth->free_func(ptr);
 243 }
 244
 245 /* Non-static so we can use it in context_internal_test */
 246 static int openssl_ctx_init_index(OPENSSL_CTX *ctx, int static_index,
 247                                   const OPENSSL_CTX_METHOD *meth)
 248 {
 249     int idx;
 250
 251     ctx = openssl_ctx_get_concrete(ctx);
 252     if (ctx == NULL)
 253         return 0;
 254
 255     idx = crypto_get_ex_new_index_ex(ctx, CRYPTO_EX_INDEX_OPENSSL_CTX, 0,
 256                                      (void *)meth,
 257                                      openssl_ctx_generic_new,
 258                                      NULL, openssl_ctx_generic_free);
 259     if (idx < 0)
 260         return 0;
 261
 262     ctx->dyn_indexes[static_index] = idx;
 263     return 1;
 264 }
 265
 266 void *openssl_ctx_get_data(OPENSSL_CTX *ctx, int index,
 267                            const OPENSSL_CTX_METHOD *meth)
 268 {
 269     void *data = NULL;
 270     int dynidx;
 271
 272     ctx = openssl_ctx_get_concrete(ctx);
 273     if (ctx == NULL)
 274         return NULL;
 275
 276     CRYPTO_THREAD_read_lock(ctx->lock);
 277     dynidx = ctx->dyn_indexes[index];
 278     CRYPTO_THREAD_unlock(ctx->lock);
 279
 280     if (dynidx != -1) {
 281         CRYPTO_THREAD_read_lock(ctx->index_locks[index]);
 282         data = CRYPTO_get_ex_data(&ctx->data, dynidx);
 283         CRYPTO_THREAD_unlock(ctx->index_locks[index]);
 284         return data;
 285     }
 286
 287     CRYPTO_THREAD_write_lock(ctx->index_locks[index]);
 288     CRYPTO_THREAD_write_lock(ctx->lock);
 289
 290     dynidx = ctx->dyn_indexes[index];
 291     if (dynidx != -1) {
 292         CRYPTO_THREAD_unlock(ctx->lock);
 293         data = CRYPTO_get_ex_data(&ctx->data, dynidx);
 294         CRYPTO_THREAD_unlock(ctx->index_locks[index]);
 295         return data;
 296     }
 297
 298     if (!openssl_ctx_init_index(ctx, index, meth)) {
 299         CRYPTO_THREAD_unlock(ctx->lock);
 300         CRYPTO_THREAD_unlock(ctx->index_locks[index]);
 301         return NULL;
 302     }
 303
 304     CRYPTO_THREAD_unlock(ctx->lock);
 305
 306     /* The alloc call ensures there's a value there */
 307     if (CRYPTO_alloc_ex_data(CRYPTO_EX_INDEX_OPENSSL_CTX, NULL,
 308                              &ctx->data, ctx->dyn_indexes[index]))
 309         data = CRYPTO_get_ex_data(&ctx->data, ctx->dyn_indexes[index]);
 310
 311     CRYPTO_THREAD_unlock(ctx->index_locks[index]);
 312
 313     return data;
 314 }
 315
 316 OSSL_EX_DATA_GLOBAL *openssl_ctx_get_ex_data_global(OPENSSL_CTX *ctx)
 317 {
 318     ctx = openssl_ctx_get_concrete(ctx);
 319     if (ctx == NULL)
 320         return NULL;
 321     return &ctx->global;
 322 }
 323
 324 int openssl_ctx_run_once(OPENSSL_CTX *ctx, unsigned int idx,
 325                          openssl_ctx_run_once_fn run_once_fn)
 326 {
 327     int done = 0, ret = 0;
 328
 329     ctx = openssl_ctx_get_concrete(ctx);
 330     if (ctx == NULL)
 331         return 0;
 332
 333     CRYPTO_THREAD_read_lock(ctx->oncelock);
 334     done = ctx->run_once_done[idx];
 335     if (done)
 336         ret = ctx->run_once_ret[idx];
 337     CRYPTO_THREAD_unlock(ctx->oncelock);
 338
 339     if (done)
 340         return ret;
 341
 342     CRYPTO_THREAD_write_lock(ctx->oncelock);
 343     if (ctx->run_once_done[idx]) {
 344         ret = ctx->run_once_ret[idx];
 345         CRYPTO_THREAD_unlock(ctx->oncelock);
 346         return ret;
 347     }
 348
 349     ret = run_once_fn(ctx);
 350     ctx->run_once_done[idx] = 1;
 351     ctx->run_once_ret[idx] = ret;
 352     CRYPTO_THREAD_unlock(ctx->oncelock);
 353
 354     return ret;
 355 }
 356
 357 int openssl_ctx_onfree(OPENSSL_CTX *ctx, openssl_ctx_onfree_fn onfreefn)
 358 {
 359     struct openssl_ctx_onfree_list_st *newonfree
 360         = OPENSSL_malloc(sizeof(*newonfree));
 361
 362     if (newonfree == NULL)
 363         return 0;
 364
 365     newonfree->fn = onfreefn;
 366     newonfree->next = ctx->onfreelist;
 367     ctx->onfreelist = newonfree;
 368
 369     return 1;
 370 }