test/drbgtest.c

   1 /*
   2  * Copyright 2011-2018 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (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 <string.h>
  11 #include "internal/nelem.h"
  12 #include <openssl/crypto.h>
  13 #include <openssl/err.h>
  14 #include <openssl/rand.h>
  15 #include <openssl/obj_mac.h>
  16 #include <openssl/evp.h>
  17 #include <openssl/aes.h>
  18 #include "../crypto/rand/rand_lcl.h"
  19
  20 #include "testutil.h"
  21 #include "drbgtest.h"
  22
  23 typedef struct drbg_selftest_data_st {
  24     int post;
  25     int nid;
  26     unsigned int flags;
  27
  28     /* KAT data for no PR */
  29     const unsigned char *entropy;
  30     size_t entropylen;
  31     const unsigned char *nonce;
  32     size_t noncelen;
  33     const unsigned char *pers;
  34     size_t perslen;
  35     const unsigned char *adin;
  36     size_t adinlen;
  37     const unsigned char *entropyreseed;
  38     size_t entropyreseedlen;
  39     const unsigned char *adinreseed;
  40     size_t adinreseedlen;
  41     const unsigned char *adin2;
  42     size_t adin2len;
  43     const unsigned char *expected;
  44     size_t exlen;
  45     const unsigned char *kat2;
  46     size_t kat2len;
  47
  48     /* KAT data for PR */
  49     const unsigned char *entropy_pr;
  50     size_t entropylen_pr;
  51     const unsigned char *nonce_pr;
  52     size_t noncelen_pr;
  53     const unsigned char *pers_pr;
  54     size_t perslen_pr;
  55     const unsigned char *adin_pr;
  56     size_t adinlen_pr;
  57     const unsigned char *entropypr_pr;
  58     size_t entropyprlen_pr;
  59     const unsigned char *ading_pr;
  60     size_t adinglen_pr;
  61     const unsigned char *entropyg_pr;
  62     size_t entropyglen_pr;
  63     const unsigned char *kat_pr;
  64     size_t katlen_pr;
  65     const unsigned char *kat2_pr;
  66     size_t kat2len_pr;
  67 } DRBG_SELFTEST_DATA;
  68
  69 #define make_drbg_test_data(nid, flag, pr, post) {\
  70     post, nid, flag, \
  71     pr##_entropyinput, sizeof(pr##_entropyinput), \
  72     pr##_nonce, sizeof(pr##_nonce), \
  73     pr##_personalizationstring, sizeof(pr##_personalizationstring), \
  74     pr##_additionalinput, sizeof(pr##_additionalinput), \
  75     pr##_entropyinputreseed, sizeof(pr##_entropyinputreseed), \
  76     pr##_additionalinputreseed, sizeof(pr##_additionalinputreseed), \
  77     pr##_additionalinput2, sizeof(pr##_additionalinput2), \
  78     pr##_int_returnedbits, sizeof(pr##_int_returnedbits), \
  79     pr##_returnedbits, sizeof(pr##_returnedbits), \
  80     pr##_pr_entropyinput, sizeof(pr##_pr_entropyinput), \
  81     pr##_pr_nonce, sizeof(pr##_pr_nonce), \
  82     pr##_pr_personalizationstring, sizeof(pr##_pr_personalizationstring), \
  83     pr##_pr_additionalinput, sizeof(pr##_pr_additionalinput), \
  84     pr##_pr_entropyinputpr, sizeof(pr##_pr_entropyinputpr), \
  85     pr##_pr_additionalinput2, sizeof(pr##_pr_additionalinput2), \
  86     pr##_pr_entropyinputpr2, sizeof(pr##_pr_entropyinputpr2), \
  87     pr##_pr_int_returnedbits, sizeof(pr##_pr_int_returnedbits), \
  88     pr##_pr_returnedbits, sizeof(pr##_pr_returnedbits) \
  89     }
  90
  91 #define make_drbg_test_data_use_df(nid, pr, p) \
  92     make_drbg_test_data(nid, 0, pr, p)
  93
  94 #define make_drbg_test_data_no_df(nid, pr, p)                      \
  95     make_drbg_test_data(nid, RAND_DRBG_FLAG_CTR_NO_DF, pr, p)
  96
  97 static DRBG_SELFTEST_DATA drbg_test[] = {
  98     make_drbg_test_data_no_df (NID_aes_128_ctr, aes_128_no_df,  0),
  99     make_drbg_test_data_no_df (NID_aes_192_ctr, aes_192_no_df,  0),
 100     make_drbg_test_data_no_df (NID_aes_256_ctr, aes_256_no_df,  1),
 101     make_drbg_test_data_use_df(NID_aes_128_ctr, aes_128_use_df, 0),
 102     make_drbg_test_data_use_df(NID_aes_192_ctr, aes_192_use_df, 0),
 103     make_drbg_test_data_use_df(NID_aes_256_ctr, aes_256_use_df, 1),
 104 };
 105
 106 static int app_data_index;
 107
 108 /*
 109  * Test context data, attached as EXDATA to the RAND_DRBG
 110  */
 111 typedef struct test_ctx_st {
 112     const unsigned char *entropy;
 113     size_t entropylen;
 114     int entropycnt;
 115     const unsigned char *nonce;
 116     size_t noncelen;
 117     int noncecnt;
 118 } TEST_CTX;
 119
 120 static size_t kat_entropy(RAND_DRBG *drbg, unsigned char **pout,
 121                           int entropy, size_t min_len, size_t max_len,
 122                           int prediction_resistance)
 123 {
 124     TEST_CTX *t = (TEST_CTX *)RAND_DRBG_get_ex_data(drbg, app_data_index);
 125
 126     t->entropycnt++;
 127     *pout = (unsigned char *)t->entropy;
 128     return t->entropylen;
 129 }
 130
 131 static size_t kat_nonce(RAND_DRBG *drbg, unsigned char **pout,
 132                         int entropy, size_t min_len, size_t max_len)
 133 {
 134     TEST_CTX *t = (TEST_CTX *)RAND_DRBG_get_ex_data(drbg, app_data_index);
 135
 136     t->noncecnt++;
 137     *pout = (unsigned char *)t->nonce;
 138     return t->noncelen;
 139 }
 140
 141 static int uninstantiate(RAND_DRBG *drbg)
 142 {
 143     int ret = drbg == NULL ? 1 : RAND_DRBG_uninstantiate(drbg);
 144
 145     ERR_clear_error();
 146     return ret;
 147 }
 148
 149 /*
 150  * Do a single KAT test.  Return 0 on failure.
 151  */
 152 static int single_kat(DRBG_SELFTEST_DATA *td)
 153 {
 154     RAND_DRBG *drbg = NULL;
 155     TEST_CTX t;
 156     int failures = 0;
 157     unsigned char buff[1024];
 158
 159     /*
 160      * Test without PR: Instantiate DRBG with test entropy, nonce and
 161      * personalisation string.
 162      */
 163     if (!TEST_ptr(drbg = RAND_DRBG_new(td->nid, td->flags, NULL)))
 164         return 0;
 165     if (!TEST_true(RAND_DRBG_set_callbacks(drbg, kat_entropy, NULL,
 166                                            kat_nonce, NULL))) {
 167         failures++;
 168         goto err;
 169     }
 170     memset(&t, 0, sizeof(t));
 171     t.entropy = td->entropy;
 172     t.entropylen = td->entropylen;
 173     t.nonce = td->nonce;
 174     t.noncelen = td->noncelen;
 175     RAND_DRBG_set_ex_data(drbg, app_data_index, &t);
 176
 177     if (!TEST_true(RAND_DRBG_instantiate(drbg, td->pers, td->perslen))
 178             || !TEST_true(RAND_DRBG_generate(drbg, buff, td->exlen, 0,
 179                                              td->adin, td->adinlen))
 180             || !TEST_mem_eq(td->expected, td->exlen, buff, td->exlen))
 181         failures++;
 182
 183     /* Reseed DRBG with test entropy and additional input */
 184     t.entropy = td->entropyreseed;
 185     t.entropylen = td->entropyreseedlen;
 186     if (!TEST_true(RAND_DRBG_reseed(drbg, td->adinreseed, td->adinreseedlen, 0)
 187             || !TEST_true(RAND_DRBG_generate(drbg, buff, td->kat2len, 0,
 188                                              td->adin2, td->adin2len))
 189             || !TEST_mem_eq(td->kat2, td->kat2len, buff, td->kat2len)))
 190         failures++;
 191     uninstantiate(drbg);
 192
 193     /*
 194      * Now test with PR: Instantiate DRBG with test entropy, nonce and
 195      * personalisation string.
 196      */
 197     if (!TEST_true(RAND_DRBG_set(drbg, td->nid, td->flags))
 198             || !TEST_true(RAND_DRBG_set_callbacks(drbg, kat_entropy, NULL,
 199                                                   kat_nonce, NULL)))
 200         failures++;
 201     RAND_DRBG_set_ex_data(drbg, app_data_index, &t);
 202     t.entropy = td->entropy_pr;
 203     t.entropylen = td->entropylen_pr;
 204     t.nonce = td->nonce_pr;
 205     t.noncelen = td->noncelen_pr;
 206     t.entropycnt = 0;
 207     t.noncecnt = 0;
 208     if (!TEST_true(RAND_DRBG_instantiate(drbg, td->pers_pr, td->perslen_pr)))
 209         failures++;
 210
 211     /*
 212      * Now generate with PR: we need to supply entropy as this will
 213      * perform a reseed operation.
 214      */
 215     t.entropy = td->entropypr_pr;
 216     t.entropylen = td->entropyprlen_pr;
 217     if (!TEST_true(RAND_DRBG_generate(drbg, buff, td->katlen_pr, 1,
 218                                       td->adin_pr, td->adinlen_pr))
 219             || !TEST_mem_eq(td->kat_pr, td->katlen_pr, buff, td->katlen_pr))
 220         failures++;
 221
 222     /*
 223      * Now generate again with PR: supply new entropy again.
 224      */
 225     t.entropy = td->entropyg_pr;
 226     t.entropylen = td->entropyglen_pr;
 227
 228     if (!TEST_true(RAND_DRBG_generate(drbg, buff, td->kat2len_pr, 1,
 229                                       td->ading_pr, td->adinglen_pr))
 230                 || !TEST_mem_eq(td->kat2_pr, td->kat2len_pr,
 231                                 buff, td->kat2len_pr))
 232         failures++;
 233
 234 err:
 235     uninstantiate(drbg);
 236     RAND_DRBG_free(drbg);
 237     return failures == 0;
 238 }
 239
 240 /*
 241  * Initialise a DRBG based on selftest data
 242  */
 243 static int init(RAND_DRBG *drbg, DRBG_SELFTEST_DATA *td, TEST_CTX *t)
 244 {
 245     if (!TEST_true(RAND_DRBG_set(drbg, td->nid, td->flags))
 246             || !TEST_true(RAND_DRBG_set_callbacks(drbg, kat_entropy, NULL,
 247                                                   kat_nonce, NULL)))
 248         return 0;
 249     RAND_DRBG_set_ex_data(drbg, app_data_index, t);
 250     t->entropy = td->entropy;
 251     t->entropylen = td->entropylen;
 252     t->nonce = td->nonce;
 253     t->noncelen = td->noncelen;
 254     t->entropycnt = 0;
 255     t->noncecnt = 0;
 256     return 1;
 257 }
 258
 259 /*
 260  * Initialise and instantiate DRBG based on selftest data
 261  */
 262 static int instantiate(RAND_DRBG *drbg, DRBG_SELFTEST_DATA *td,
 263                        TEST_CTX *t)
 264 {
 265     if (!TEST_true(init(drbg, td, t))
 266             || !TEST_true(RAND_DRBG_instantiate(drbg, td->pers, td->perslen)))
 267         return 0;
 268     return 1;
 269 }
 270
 271 /*
 272  * Perform extensive error checking as required by SP800-90.
 273  * Induce several failure modes and check an error condition is set.
 274  */
 275 static int error_check(DRBG_SELFTEST_DATA *td)
 276 {
 277     static char zero[sizeof(RAND_DRBG)];
 278     RAND_DRBG *drbg = NULL;
 279     TEST_CTX t;
 280     unsigned char buff[1024];
 281     unsigned int generate_counter_tmp;
 282     int ret = 0;
 283
 284     if (!TEST_ptr(drbg = RAND_DRBG_new(0, 0, NULL)))
 285         goto err;
 286
 287     /*
 288      * Personalisation string tests
 289      */
 290
 291     /* Test detection of too large personlisation string */
 292     if (!init(drbg, td, &t)
 293             || RAND_DRBG_instantiate(drbg, td->pers, drbg->max_perslen + 1) > 0)
 294         goto err;
 295
 296     /*
 297      * Entropy source tests
 298      */
 299
 300     /* Test entropy source failure detecion: i.e. returns no data */
 301     t.entropylen = 0;
 302     if (TEST_int_le(RAND_DRBG_instantiate(drbg, td->pers, td->perslen), 0))
 303         goto err;
 304
 305     /* Try to generate output from uninstantiated DRBG */
 306     if (!TEST_false(RAND_DRBG_generate(drbg, buff, td->exlen, 0,
 307                                        td->adin, td->adinlen))
 308             || !uninstantiate(drbg))
 309         goto err;
 310
 311     /* Test insufficient entropy */
 312     t.entropylen = drbg->min_entropylen - 1;
 313     if (!init(drbg, td, &t)
 314             || RAND_DRBG_instantiate(drbg, td->pers, td->perslen) > 0
 315             || !uninstantiate(drbg))
 316         goto err;
 317
 318     /* Test too much entropy */
 319     t.entropylen = drbg->max_entropylen + 1;
 320     if (!init(drbg, td, &t)
 321             || RAND_DRBG_instantiate(drbg, td->pers, td->perslen) > 0
 322             || !uninstantiate(drbg))
 323         goto err;
 324
 325     /*
 326      * Nonce tests
 327      */
 328
 329     /* Test too small nonce */
 330     if (drbg->min_noncelen) {
 331         t.noncelen = drbg->min_noncelen - 1;
 332         if (!init(drbg, td, &t)
 333                 || RAND_DRBG_instantiate(drbg, td->pers, td->perslen) > 0
 334                 || !uninstantiate(drbg))
 335             goto err;
 336     }
 337
 338     /* Test too large nonce */
 339     if (drbg->max_noncelen) {
 340         t.noncelen = drbg->max_noncelen + 1;
 341         if (!init(drbg, td, &t)
 342                 || RAND_DRBG_instantiate(drbg, td->pers, td->perslen) > 0
 343                 || !uninstantiate(drbg))
 344             goto err;
 345     }
 346
 347     /* Instantiate with valid data, Check generation is now OK */
 348     if (!instantiate(drbg, td, &t)
 349             || !TEST_true(RAND_DRBG_generate(drbg, buff, td->exlen, 0,
 350                                              td->adin, td->adinlen)))
 351         goto err;
 352
 353     /* Request too much data for one request */
 354     if (!TEST_false(RAND_DRBG_generate(drbg, buff, drbg->max_request + 1, 0,
 355                                        td->adin, td->adinlen)))
 356         goto err;
 357
 358     /* Try too large additional input */
 359     if (!TEST_false(RAND_DRBG_generate(drbg, buff, td->exlen, 0,
 360                                        td->adin, drbg->max_adinlen + 1)))
 361         goto err;
 362
 363     /*
 364      * Check prediction resistance request fails if entropy source
 365      * failure.
 366      */
 367     t.entropylen = 0;
 368     if (TEST_false(RAND_DRBG_generate(drbg, buff, td->exlen, 1,
 369                                       td->adin, td->adinlen))
 370             || !uninstantiate(drbg))
 371         goto err;
 372
 373     /* Instantiate again with valid data */
 374     if (!instantiate(drbg, td, &t))
 375         goto err;
 376     generate_counter_tmp = drbg->generate_counter;
 377     drbg->generate_counter = drbg->reseed_interval;
 378
 379     /* Generate output and check entropy has been requested for reseed */
 380     t.entropycnt = 0;
 381     if (!TEST_true(RAND_DRBG_generate(drbg, buff, td->exlen, 0,
 382                                       td->adin, td->adinlen))
 383             || !TEST_int_eq(t.entropycnt, 1)
 384             || !TEST_int_eq(drbg->generate_counter, generate_counter_tmp + 1)
 385             || !uninstantiate(drbg))
 386         goto err;
 387
 388     /*
 389      * Check prediction resistance request fails if entropy source
 390      * failure.
 391      */
 392     t.entropylen = 0;
 393     if (!TEST_false(RAND_DRBG_generate(drbg, buff, td->exlen, 1,
 394                                        td->adin, td->adinlen))
 395             || !uninstantiate(drbg))
 396         goto err;
 397
 398     /* Test reseed counter works */
 399     if (!instantiate(drbg, td, &t))
 400         goto err;
 401     generate_counter_tmp = drbg->generate_counter;
 402     drbg->generate_counter = drbg->reseed_interval;
 403
 404     /* Generate output and check entropy has been requested for reseed */
 405     t.entropycnt = 0;
 406     if (!TEST_true(RAND_DRBG_generate(drbg, buff, td->exlen, 0,
 407                                       td->adin, td->adinlen))
 408             || !TEST_int_eq(t.entropycnt, 1)
 409             || !TEST_int_eq(drbg->generate_counter, generate_counter_tmp + 1)
 410             || !uninstantiate(drbg))
 411         goto err;
 412
 413     /*
 414      * Explicit reseed tests
 415      */
 416
 417     /* Test explicit reseed with too large additional input */
 418     if (!init(drbg, td, &t)
 419             || RAND_DRBG_reseed(drbg, td->adin, drbg->max_adinlen + 1, 0) > 0)
 420         goto err;
 421
 422     /* Test explicit reseed with entropy source failure */
 423     t.entropylen = 0;
 424     if (!TEST_int_le(RAND_DRBG_reseed(drbg, td->adin, td->adinlen, 0), 0)
 425             || !uninstantiate(drbg))
 426         goto err;
 427
 428     /* Test explicit reseed with too much entropy */
 429     if (!init(drbg, td, &t))
 430         goto err;
 431     t.entropylen = drbg->max_entropylen + 1;
 432     if (!TEST_int_le(RAND_DRBG_reseed(drbg, td->adin, td->adinlen, 0), 0)
 433             || !uninstantiate(drbg))
 434         goto err;
 435
 436     /* Test explicit reseed with too little entropy */
 437     if (!init(drbg, td, &t))
 438         goto err;
 439     t.entropylen = drbg->min_entropylen - 1;
 440     if (!TEST_int_le(RAND_DRBG_reseed(drbg, td->adin, td->adinlen, 0), 0)
 441             || !uninstantiate(drbg))
 442         goto err;
 443
 444     /* Standard says we have to check uninstantiate really zeroes */
 445     if (!TEST_mem_eq(zero, sizeof(drbg->data), &drbg->data, sizeof(drbg->data)))
 446         goto err;
 447
 448     ret = 1;
 449
 450 err:
 451     uninstantiate(drbg);
 452     RAND_DRBG_free(drbg);
 453     return ret;
 454 }
 455
 456 static int test_kats(int i)
 457 {
 458     DRBG_SELFTEST_DATA *td = &drbg_test[i];
 459     int rv = 0;
 460
 461     if (!single_kat(td))
 462         goto err;
 463     rv = 1;
 464
 465 err:
 466     return rv;
 467 }
 468
 469 static int test_error_checks(int i)
 470 {
 471     DRBG_SELFTEST_DATA *td = &drbg_test[i];
 472     int rv = 0;
 473
 474     if (error_check(td))
 475         goto err;
 476     rv = 1;
 477
 478 err:
 479     return rv;
 480 }
 481
 482 /*
 483  * Hook context data, attached as EXDATA to the RAND_DRBG
 484  */
 485 typedef struct hook_ctx_st {
 486     RAND_DRBG *drbg;
 487     /*
 488      * Currently, all DRBGs use the same get_entropy() callback.
 489      * The tests however, don't assume this and store
 490      * the original callback for every DRBG separately.
 491      */
 492     RAND_DRBG_get_entropy_fn get_entropy;
 493     /* forces a failure of the get_entropy() call if nonzero */
 494     int fail;
 495     /* counts successful reseeds */
 496     int reseed_count;
 497 } HOOK_CTX;
 498
 499 static HOOK_CTX master_ctx, public_ctx, private_ctx;
 500
 501 static HOOK_CTX *get_hook_ctx(RAND_DRBG *drbg)
 502 {
 503     return (HOOK_CTX *)RAND_DRBG_get_ex_data(drbg, app_data_index);
 504 }
 505
 506 /* Intercepts and counts calls to the get_entropy() callback */
 507 static size_t get_entropy_hook(RAND_DRBG *drbg, unsigned char **pout,
 508                               int entropy, size_t min_len, size_t max_len,
 509                               int prediction_resistance)
 510 {
 511     size_t ret;
 512     HOOK_CTX *ctx = get_hook_ctx(drbg);
 513
 514     if (ctx->fail != 0)
 515         return 0;
 516
 517     ret = ctx->get_entropy(drbg, pout, entropy, min_len, max_len,
 518                            prediction_resistance);
 519
 520     if (ret != 0)
 521         ctx->reseed_count++;
 522     return ret;
 523 }
 524
 525 /* Installs a hook for the get_entropy() callback of the given drbg */
 526 static void hook_drbg(RAND_DRBG *drbg, HOOK_CTX *ctx)
 527 {
 528     memset(ctx, 0, sizeof(*ctx));
 529     ctx->drbg = drbg;
 530     ctx->get_entropy = drbg->get_entropy;
 531     drbg->get_entropy = get_entropy_hook;
 532     RAND_DRBG_set_ex_data(drbg, app_data_index, ctx);
 533 }
 534
 535 /* Installs the hook for the get_entropy() callback of the given drbg */
 536 static void unhook_drbg(RAND_DRBG *drbg)
 537 {
 538     HOOK_CTX *ctx = get_hook_ctx(drbg);
 539
 540     drbg->get_entropy = ctx->get_entropy;
 541     CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DRBG, drbg, &drbg->ex_data);
 542 }
 543
 544 /* Resets the given hook context */
 545 static void reset_hook_ctx(HOOK_CTX *ctx)
 546 {
 547     ctx->fail = 0;
 548     ctx->reseed_count = 0;
 549 }
 550
 551 /* Resets all drbg hook contexts */
 552 static void reset_drbg_hook_ctx()
 553 {
 554     reset_hook_ctx(&master_ctx);
 555     reset_hook_ctx(&public_ctx);
 556     reset_hook_ctx(&private_ctx);
 557 }
 558
 559 /*
 560  * Generates random output using RAND_bytes() and RAND_priv_bytes()
 561  * and checks whether the three shared DRBGs were reseeded as
 562  * expected.
 563  *
 564  * |expect_success|: expected outcome (as reported by RAND_status())
 565  * |master|, |public|, |private|: pointers to the three shared DRBGs
 566  * |expect_xxx_reseed| =
 567  *       1:  it is expected that the specified DRBG is reseeded
 568  *       0:  it is expected that the specified DRBG is not reseeded
 569  *      -1:  don't check whether the specified DRBG was reseeded or not
 570  */
 571 static int test_drbg_reseed(int expect_success,
 572                             RAND_DRBG *master,
 573                             RAND_DRBG *public,
 574                             RAND_DRBG *private,
 575                             int expect_master_reseed,
 576                             int expect_public_reseed,
 577                             int expect_private_reseed
 578                            )
 579 {
 580     unsigned char buf[32];
 581     time_t before_reseed, after_reseed;
 582     int expected_state = (expect_success ? DRBG_READY : DRBG_ERROR);
 583
 584     /*
 585      * step 1: check preconditions
 586      */
 587
 588     /* Test whether seed propagation is enabled */
 589     if (!TEST_int_ne(master->reseed_counter, 0)
 590         || !TEST_int_ne(public->reseed_counter, 0)
 591         || !TEST_int_ne(private->reseed_counter, 0))
 592         return 0;
 593
 594     /* Check whether the master DRBG's reseed counter is the largest one */
 595     if (!TEST_int_le(public->reseed_counter, master->reseed_counter)
 596         || !TEST_int_le(private->reseed_counter, master->reseed_counter))
 597         return 0;
 598
 599     /*
 600      * step 2: generate random output
 601      */
 602
 603     /* Generate random output from the public and private DRBG */
 604     before_reseed = expect_master_reseed == 1 ? time(NULL) : 0;
 605     if (!TEST_int_eq(RAND_bytes(buf, sizeof(buf)), expect_success)
 606         || !TEST_int_eq(RAND_priv_bytes(buf, sizeof(buf)), expect_success))
 607         return 0;
 608     after_reseed = time(NULL);
 609
 610
 611     /*
 612      * step 3: check postconditions
 613      */
 614
 615     /* Test whether reseeding succeeded as expected */
 616     if (!TEST_int_eq(master->state, expected_state)
 617         || !TEST_int_eq(public->state, expected_state)
 618         || !TEST_int_eq(private->state, expected_state))
 619         return 0;
 620
 621     if (expect_master_reseed >= 0) {
 622         /* Test whether master DRBG was reseeded as expected */
 623         if (!TEST_int_eq(master_ctx.reseed_count, expect_master_reseed))
 624             return 0;
 625     }
 626
 627     if (expect_public_reseed >= 0) {
 628         /* Test whether public DRBG was reseeded as expected */
 629         if (!TEST_int_eq(public_ctx.reseed_count, expect_public_reseed))
 630             return 0;
 631     }
 632
 633     if (expect_private_reseed >= 0) {
 634         /* Test whether public DRBG was reseeded as expected */
 635         if (!TEST_int_eq(private_ctx.reseed_count, expect_private_reseed))
 636             return 0;
 637     }
 638
 639     if (expect_success == 1) {
 640         /* Test whether all three reseed counters are synchronized */
 641         if (!TEST_int_eq(public->reseed_counter, master->reseed_counter)
 642             || !TEST_int_eq(private->reseed_counter, master->reseed_counter))
 643             return 0;
 644
 645         /* Test whether reseed time of master DRBG is set correctly */
 646         if (!TEST_time_t_le(before_reseed, master->reseed_time)
 647             || !TEST_time_t_le(master->reseed_time, after_reseed))
 648             return 0;
 649
 650         /* Test whether reseed times of child DRBGs are synchronized with master */
 651         if (!TEST_time_t_ge(public->reseed_time, master->reseed_time)
 652             || !TEST_time_t_ge(private->reseed_time, master->reseed_time))
 653             return 0;
 654     } else {
 655         ERR_clear_error();
 656     }
 657
 658     return 1;
 659 }
 660
 661 /*
 662  * Test whether the default rand_method (RAND_OpenSSL()) is
 663  * setup correctly, in particular whether reseeding  works
 664  * as designed.
 665  */
 666 static int test_rand_reseed(void)
 667 {
 668     RAND_DRBG *master, *public, *private;
 669     unsigned char rand_add_buf[256];
 670     int rv=0;
 671
 672     /* Check whether RAND_OpenSSL() is the default method */
 673     if (!TEST_ptr_eq(RAND_get_rand_method(), RAND_OpenSSL()))
 674         return 0;
 675
 676     /* All three DRBGs should be non-null */
 677     if (!TEST_ptr(master = RAND_DRBG_get0_master())
 678         || !TEST_ptr(public = RAND_DRBG_get0_public())
 679         || !TEST_ptr(private = RAND_DRBG_get0_private()))
 680         return 0;
 681
 682     /* There should be three distinct DRBGs, two of them chained to master */
 683     if (!TEST_ptr_ne(public, private)
 684         || !TEST_ptr_ne(public, master)
 685         || !TEST_ptr_ne(private, master)
 686         || !TEST_ptr_eq(public->parent, master)
 687         || !TEST_ptr_eq(private->parent, master))
 688         return 0;
 689
 690     /* Install hooks for the following tests */
 691     hook_drbg(master,  &master_ctx);
 692     hook_drbg(public,  &public_ctx);
 693     hook_drbg(private, &private_ctx);
 694
 695     /*
 696      * Test initial state of shared DRBs
 697      */
 698     if (!TEST_true(test_drbg_reseed(1, master, public, private, 0, 0, 0)))
 699         goto error;
 700     reset_drbg_hook_ctx();
 701
 702     /*
 703      * Test whether the public and private DRBG are both reseeded when their
 704      * reseed counters differ from the master's reseed counter.
 705      */
 706     master->reseed_counter++;
 707     if (!TEST_true(test_drbg_reseed(1, master, public, private, 0, 1, 1)))
 708         goto error;
 709     reset_drbg_hook_ctx();
 710
 711     /*
 712      * Test whether the public DRBG is reseeded when its reseed counter differs
 713      * from the master's reseed counter.
 714      */
 715     master->reseed_counter++;
 716     private->reseed_counter++;
 717     if (!TEST_true(test_drbg_reseed(1, master, public, private, 0, 1, 0)))
 718         goto error;
 719     reset_drbg_hook_ctx();
 720
 721     /*
 722      * Test whether the private DRBG is reseeded when its reseed counter differs
 723      * from the master's reseed counter.
 724      */
 725     master->reseed_counter++;
 726     public->reseed_counter++;
 727     if (!TEST_true(test_drbg_reseed(1, master, public, private, 0, 0, 1)))
 728         goto error;
 729     reset_drbg_hook_ctx();
 730
 731
 732     /* fill 'randomness' buffer with some arbitrary data */
 733     memset(rand_add_buf, 'r', sizeof(rand_add_buf));
 734
 735     /*
 736      * Test whether all three DRBGs are reseeded by RAND_add()
 737      */
 738     RAND_add(rand_add_buf, sizeof(rand_add_buf), sizeof(rand_add_buf));
 739     if (!TEST_true(test_drbg_reseed(1, master, public, private, 1, 1, 1)))
 740         goto error;
 741     reset_drbg_hook_ctx();
 742
 743
 744     /*
 745      * Test whether none of the DRBGs is reseed if the master fails to reseed
 746      */
 747     master_ctx.fail = 1;
 748     master->reseed_counter++;
 749     RAND_add(rand_add_buf, sizeof(rand_add_buf), sizeof(rand_add_buf));
 750     if (!TEST_true(test_drbg_reseed(0, master, public, private, 0, 0, 0)))
 751         goto error;
 752     reset_drbg_hook_ctx();
 753
 754     rv = 1;
 755
 756 error:
 757     /* Remove hooks  */
 758     unhook_drbg(master);
 759     unhook_drbg(public);
 760     unhook_drbg(private);
 761
 762     return rv;
 763 }
 764
 765
 766 int setup_tests(void)
 767 {
 768     app_data_index = RAND_DRBG_get_ex_new_index(0L, NULL, NULL, NULL, NULL);
 769
 770     ADD_ALL_TESTS(test_kats, OSSL_NELEM(drbg_test));
 771     ADD_ALL_TESTS(test_error_checks, OSSL_NELEM(drbg_test));
 772     ADD_TEST(test_rand_reseed);
 773     return 1;
 774 }