X-Git-Url: https://git.openssl.org/?p=openssl.git;a=blobdiff_plain;f=crypto%2Frand%2Fdrbg_lib.c;h=cc59236bcc84a92a78aaa563c70c6441bdeb2c0f;hp=0042a931b0a1291ebf64bc29f88faa896ef01487;hb=560096f804a3712eea161726a8f085beefe8838a;hpb=e0b625f9db00509af9004b7907d44b78f332754a diff --git a/crypto/rand/drbg_lib.c b/crypto/rand/drbg_lib.c index 0042a931b0..cc59236bcc 100644 --- a/crypto/rand/drbg_lib.c +++ b/crypto/rand/drbg_lib.c @@ -1,5 +1,5 @@ /* - * Copyright 2011-2017 The OpenSSL Project Authors. All Rights Reserved. + * Copyright 2011-2018 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the OpenSSL license (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy @@ -14,16 +14,12 @@ #include "rand_lcl.h" #include "internal/thread_once.h" #include "internal/rand_int.h" - -static RAND_DRBG rand_drbg; /* The default global DRBG. */ -static RAND_DRBG priv_drbg; /* The global private-key DRBG. */ - -/* NIST SP 800-90A DRBG recommends the use of a personalization string. */ -static const char ossl_pers_string[] = "OpenSSL NIST SP 800-90A DRBG"; +#include "internal/cryptlib_int.h" /* - * Support framework for NIST SP 800-90A DRBG, AES-CTR mode. - * The RAND_DRBG is OpenSSL's pointer to an instance of the DRBG. + * Support framework for NIST SP 800-90A DRBG + * + * See manual page RAND_DRBG(7) for a general overview. * * The OpenSSL model is to have new and free functions, and that new * does all initialization. That is not the NIST model, which has @@ -33,73 +29,220 @@ static const char ossl_pers_string[] = "OpenSSL NIST SP 800-90A DRBG"; * a much bigger deal than just re-setting an allocated resource.) */ +/* + * The three shared DRBG instances + * + * There are three shared DRBG instances: , , and . + */ + +/* + * The DRBG + * + * Not used directly by the application, only for reseeding the two other + * DRBGs. It reseeds itself by pulling either randomness from os entropy + * sources or by consuming randomness which was added by RAND_add(). + * + * The DRBG is a global instance which is accessed concurrently by + * all threads. The necessary locking is managed automatically by its child + * DRBG instances during reseeding. + */ +static RAND_DRBG *master_drbg; +/* + * The DRBG + * + * Used by default for generating random bytes using RAND_bytes(). + * + * The DRBG is thread-local, i.e., there is one instance per thread. + */ +static CRYPTO_THREAD_LOCAL public_drbg; +/* + * The DRBG + * + * Used by default for generating private keys using RAND_priv_bytes() + * + * The DRBG is thread-local, i.e., there is one instance per thread. + */ +static CRYPTO_THREAD_LOCAL private_drbg; + + + +/* NIST SP 800-90A DRBG recommends the use of a personalization string. */ +static const char ossl_pers_string[] = "OpenSSL NIST SP 800-90A DRBG"; + static CRYPTO_ONCE rand_drbg_init = CRYPTO_ONCE_STATIC_INIT; -static int drbg_setup(RAND_DRBG *drbg, const char *name); + + +static int rand_drbg_type = RAND_DRBG_TYPE; +static unsigned int rand_drbg_flags = RAND_DRBG_FLAGS; + +static unsigned int master_reseed_interval = MASTER_RESEED_INTERVAL; +static unsigned int slave_reseed_interval = SLAVE_RESEED_INTERVAL; + +static time_t master_reseed_time_interval = MASTER_RESEED_TIME_INTERVAL; +static time_t slave_reseed_time_interval = SLAVE_RESEED_TIME_INTERVAL; + +static RAND_DRBG *drbg_setup(RAND_DRBG *parent); + +static RAND_DRBG *rand_drbg_new(int secure, + int type, + unsigned int flags, + RAND_DRBG *parent); /* - * Set/initialize |drbg| to be of type |nid|, with optional |flags|. - * Return -2 if the type is not supported, 1 on success and -1 on - * failure. + * Set/initialize |drbg| to be of type |type|, with optional |flags|. + * + * If |type| and |flags| are zero, use the defaults + * + * Returns 1 on success, 0 on failure. */ -int RAND_DRBG_set(RAND_DRBG *drbg, int nid, unsigned int flags) +int RAND_DRBG_set(RAND_DRBG *drbg, int type, unsigned int flags) { int ret = 1; + if (type == 0 && flags == 0) { + type = rand_drbg_type; + flags = rand_drbg_flags; + } + drbg->state = DRBG_UNINITIALISED; drbg->flags = flags; - drbg->nid = nid; + drbg->type = type; - switch (nid) { + switch (type) { default: RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_UNSUPPORTED_DRBG_TYPE); - return -2; + return 0; case 0: /* Uninitialized; that's okay. */ return 1; case NID_aes_128_ctr: case NID_aes_192_ctr: case NID_aes_256_ctr: - ret = ctr_init(drbg); + ret = drbg_ctr_init(drbg); break; } - if (ret < 0) + if (ret == 0) RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_ERROR_INITIALISING_DRBG); return ret; } /* - * Allocate memory and initialize a new DRBG. The |parent|, if not - * NULL, will be used to auto-seed this RAND_DRBG as needed. + * Set/initialize default |type| and |flag| for new drbg instances. + * + * Returns 1 on success, 0 on failure. */ -RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent) +int RAND_DRBG_set_defaults(int type, unsigned int flags) +{ + int ret = 1; + + switch (type) { + default: + RANDerr(RAND_F_RAND_DRBG_SET_DEFAULTS, RAND_R_UNSUPPORTED_DRBG_TYPE); + return 0; + case NID_aes_128_ctr: + case NID_aes_192_ctr: + case NID_aes_256_ctr: + break; + } + + if ((flags & ~RAND_DRBG_USED_FLAGS) != 0) { + RANDerr(RAND_F_RAND_DRBG_SET_DEFAULTS, RAND_R_UNSUPPORTED_DRBG_FLAGS); + return 0; + } + + rand_drbg_type = type; + rand_drbg_flags = flags; + + return ret; +} + + +/* + * Allocate memory and initialize a new DRBG. The DRBG is allocated on + * the secure heap if |secure| is nonzero and the secure heap is enabled. + * The |parent|, if not NULL, will be used as random source for reseeding. + * + * Returns a pointer to the new DRBG instance on success, NULL on failure. + */ +static RAND_DRBG *rand_drbg_new(int secure, + int type, + unsigned int flags, + RAND_DRBG *parent) { - RAND_DRBG *drbg = OPENSSL_zalloc(sizeof(*drbg)); + RAND_DRBG *drbg = secure ? + OPENSSL_secure_zalloc(sizeof(*drbg)) : OPENSSL_zalloc(sizeof(*drbg)); if (drbg == NULL) { RANDerr(RAND_F_RAND_DRBG_NEW, ERR_R_MALLOC_FAILURE); - goto err; + return NULL; } + + drbg->secure = secure && CRYPTO_secure_allocated(drbg); drbg->fork_count = rand_fork_count; drbg->parent = parent; - if (RAND_DRBG_set(drbg, type, flags) < 0) + + if (parent == NULL) { + drbg->get_entropy = rand_drbg_get_entropy; + drbg->cleanup_entropy = rand_drbg_cleanup_entropy; +#ifndef RAND_DRBG_GET_RANDOM_NONCE + drbg->get_nonce = rand_drbg_get_nonce; + drbg->cleanup_nonce = rand_drbg_cleanup_nonce; +#endif + + drbg->reseed_interval = master_reseed_interval; + drbg->reseed_time_interval = master_reseed_time_interval; + } else { + drbg->get_entropy = rand_drbg_get_entropy; + drbg->cleanup_entropy = rand_drbg_cleanup_entropy; + /* + * Do not provide nonce callbacks, the child DRBGs will + * obtain their nonce using random bits from the parent. + */ + + drbg->reseed_interval = slave_reseed_interval; + drbg->reseed_time_interval = slave_reseed_time_interval; + } + + if (RAND_DRBG_set(drbg, type, flags) == 0) goto err; if (parent != NULL) { - if (!RAND_DRBG_set_callbacks(drbg, rand_drbg_get_entropy, - rand_drbg_cleanup_entropy, - NULL, NULL)) + rand_drbg_lock(parent); + if (drbg->strength > parent->strength) { + /* + * We currently don't support the algorithm from NIST SP 800-90C + * 10.1.2 to use a weaker DRBG as source + */ + rand_drbg_unlock(parent); + RANDerr(RAND_F_RAND_DRBG_NEW, RAND_R_PARENT_STRENGTH_TOO_WEAK); goto err; + } + rand_drbg_unlock(parent); } return drbg; err: - OPENSSL_free(drbg); + if (drbg->secure) + OPENSSL_secure_free(drbg); + else + OPENSSL_free(drbg); + return NULL; } +RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent) +{ + return rand_drbg_new(0, type, flags, parent); +} + +RAND_DRBG *RAND_DRBG_secure_new(int type, unsigned int flags, RAND_DRBG *parent) +{ + return rand_drbg_new(1, type, flags, parent); +} + /* * Uninstantiate |drbg| and free all memory. */ @@ -108,26 +251,47 @@ void RAND_DRBG_free(RAND_DRBG *drbg) if (drbg == NULL) return; - ctr_uninstantiate(drbg); + if (drbg->meth != NULL) + drbg->meth->uninstantiate(drbg); + CRYPTO_THREAD_lock_free(drbg->lock); CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DRBG, drbg, &drbg->ex_data); - OPENSSL_clear_free(drbg, sizeof(*drbg)); + + if (drbg->secure) + OPENSSL_secure_clear_free(drbg, sizeof(*drbg)); + else + OPENSSL_clear_free(drbg, sizeof(*drbg)); } /* * Instantiate |drbg|, after it has been initialized. Use |pers| and * |perslen| as prediction-resistance input. + * + * Requires that drbg->lock is already locked for write, if non-null. + * + * Returns 1 on success, 0 on failure. */ int RAND_DRBG_instantiate(RAND_DRBG *drbg, const unsigned char *pers, size_t perslen) { unsigned char *nonce = NULL, *entropy = NULL; size_t noncelen = 0, entropylen = 0; + size_t min_entropy = drbg->strength; + size_t min_entropylen = drbg->min_entropylen; + size_t max_entropylen = drbg->max_entropylen; if (perslen > drbg->max_perslen) { RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_PERSONALISATION_STRING_TOO_LONG); goto end; } + + if (drbg->meth == NULL) + { + RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, + RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED); + goto end; + } + if (drbg->state != DRBG_UNINITIALISED) { RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, drbg->state == DRBG_ERROR ? RAND_R_IN_ERROR_STATE @@ -136,33 +300,52 @@ int RAND_DRBG_instantiate(RAND_DRBG *drbg, } drbg->state = DRBG_ERROR; + + /* + * NIST SP800-90Ar1 section 9.1 says you can combine getting the entropy + * and nonce in 1 call by increasing the entropy with 50% and increasing + * the minimum length to accomadate the length of the nonce. + * We do this in case a nonce is require and get_nonce is NULL. + */ + if (drbg->min_noncelen > 0 && drbg->get_nonce == NULL) { + min_entropy += drbg->strength / 2; + min_entropylen += drbg->min_noncelen; + max_entropylen += drbg->max_noncelen; + } + if (drbg->get_entropy != NULL) - entropylen = drbg->get_entropy(drbg, &entropy, drbg->strength, - drbg->min_entropylen, drbg->max_entropylen); - if (entropylen < drbg->min_entropylen - || entropylen > drbg->max_entropylen) { + entropylen = drbg->get_entropy(drbg, &entropy, min_entropy, + min_entropylen, max_entropylen, 0); + if (entropylen < min_entropylen + || entropylen > max_entropylen) { RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_RETRIEVING_ENTROPY); goto end; } - if (drbg->max_noncelen > 0 && drbg->get_nonce != NULL) { + if (drbg->min_noncelen > 0 && drbg->get_nonce != NULL) { noncelen = drbg->get_nonce(drbg, &nonce, drbg->strength / 2, drbg->min_noncelen, drbg->max_noncelen); if (noncelen < drbg->min_noncelen || noncelen > drbg->max_noncelen) { - RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, - RAND_R_ERROR_RETRIEVING_NONCE); + RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_RETRIEVING_NONCE); goto end; } } - if (!ctr_instantiate(drbg, entropy, entropylen, + if (!drbg->meth->instantiate(drbg, entropy, entropylen, nonce, noncelen, pers, perslen)) { RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_INSTANTIATING_DRBG); goto end; } drbg->state = DRBG_READY; - drbg->reseed_counter = 1; + drbg->generate_counter = 0; + drbg->reseed_time = time(NULL); + if (drbg->reseed_counter > 0) { + if (drbg->parent == NULL) + drbg->reseed_counter++; + else + drbg->reseed_counter = drbg->parent->reseed_counter; + } end: if (entropy != NULL && drbg->cleanup_entropy != NULL) @@ -175,7 +358,7 @@ end: RAND_R_ERROR_ENTROPY_POOL_WAS_IGNORED); drbg->state = DRBG_ERROR; } - RAND_POOL_free(drbg->pool); + rand_pool_free(drbg->pool); drbg->pool = NULL; } if (drbg->state == DRBG_READY) @@ -185,21 +368,38 @@ end: /* * Uninstantiate |drbg|. Must be instantiated before it can be used. + * + * Requires that drbg->lock is already locked for write, if non-null. + * + * Returns 1 on success, 0 on failure. */ int RAND_DRBG_uninstantiate(RAND_DRBG *drbg) { - int ret = ctr_uninstantiate(drbg); + if (drbg->meth == NULL) + { + RANDerr(RAND_F_RAND_DRBG_UNINSTANTIATE, + RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED); + return 0; + } - OPENSSL_cleanse(&drbg->ctr, sizeof(drbg->ctr)); - drbg->state = DRBG_UNINITIALISED; - return ret; + /* Clear the entire drbg->ctr struct, then reset some important + * members of the drbg->ctr struct (e.g. keysize, df_ks) to their + * initial values. + */ + drbg->meth->uninstantiate(drbg); + return RAND_DRBG_set(drbg, drbg->type, drbg->flags); } /* * Reseed |drbg|, mixing in the specified data + * + * Requires that drbg->lock is already locked for write, if non-null. + * + * Returns 1 on success, 0 on failure. */ int RAND_DRBG_reseed(RAND_DRBG *drbg, - const unsigned char *adin, size_t adinlen) + const unsigned char *adin, size_t adinlen, + int prediction_resistance) { unsigned char *entropy = NULL; size_t entropylen = 0; @@ -223,17 +423,27 @@ int RAND_DRBG_reseed(RAND_DRBG *drbg, drbg->state = DRBG_ERROR; if (drbg->get_entropy != NULL) entropylen = drbg->get_entropy(drbg, &entropy, drbg->strength, - drbg->min_entropylen, drbg->max_entropylen); + drbg->min_entropylen, + drbg->max_entropylen, + prediction_resistance); if (entropylen < drbg->min_entropylen || entropylen > drbg->max_entropylen) { RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_ERROR_RETRIEVING_ENTROPY); goto end; } - if (!ctr_reseed(drbg, entropy, entropylen, adin, adinlen)) + if (!drbg->meth->reseed(drbg, entropy, entropylen, adin, adinlen)) goto end; + drbg->state = DRBG_READY; - drbg->reseed_counter = 1; + drbg->generate_counter = 0; + drbg->reseed_time = time(NULL); + if (drbg->reseed_counter > 0) { + if (drbg->parent == NULL) + drbg->reseed_counter++; + else + drbg->reseed_counter = drbg->parent->reseed_counter; + } end: if (entropy != NULL && drbg->cleanup_entropy != NULL) @@ -269,7 +479,7 @@ int rand_drbg_restart(RAND_DRBG *drbg, if (drbg->pool != NULL) { RANDerr(RAND_F_RAND_DRBG_RESTART, ERR_R_INTERNAL_ERROR); - RAND_POOL_free(drbg->pool); + rand_pool_free(drbg->pool); drbg->pool = NULL; } @@ -287,11 +497,11 @@ int rand_drbg_restart(RAND_DRBG *drbg, } /* will be picked up by the rand_drbg_get_entropy() callback */ - drbg->pool = RAND_POOL_new(entropy, len, len); + drbg->pool = rand_pool_new(entropy, len, len); if (drbg->pool == NULL) return 0; - RAND_POOL_add(drbg->pool, buffer, len, entropy); + rand_pool_add(drbg->pool, buffer, len, entropy); } else { if (drbg->max_adinlen < len) { RANDerr(RAND_F_RAND_DRBG_RESTART, @@ -309,7 +519,10 @@ int rand_drbg_restart(RAND_DRBG *drbg, /* repair uninitialized state */ if (drbg->state == DRBG_UNINITIALISED) { - drbg_setup(drbg, NULL); + /* reinstantiate drbg */ + RAND_DRBG_instantiate(drbg, + (const unsigned char *) ossl_pers_string, + sizeof(ossl_pers_string) - 1); /* already reseeded. prevent second reseeding below */ reseeded = (drbg->state == DRBG_READY); } @@ -325,10 +538,10 @@ int rand_drbg_restart(RAND_DRBG *drbg, * entropy from the trusted entropy source using get_entropy(). * This is not a reseeding in the strict sense of NIST SP 800-90A. */ - ctr_reseed(drbg, adin, adinlen, NULL, 0); + drbg->meth->reseed(drbg, adin, adinlen, NULL, 0); } else if (reseeded == 0) { /* do a full reseeding if it has not been done yet above */ - RAND_DRBG_reseed(drbg, NULL, 0); + RAND_DRBG_reseed(drbg, NULL, 0, 0); } } @@ -336,7 +549,7 @@ int rand_drbg_restart(RAND_DRBG *drbg, if (drbg->pool != NULL) { drbg->state = DRBG_ERROR; RANDerr(RAND_F_RAND_DRBG_RESTART, ERR_R_INTERNAL_ERROR); - RAND_POOL_free(drbg->pool); + rand_pool_free(drbg->pool); drbg->pool = NULL; return 0; } @@ -349,6 +562,8 @@ int rand_drbg_restart(RAND_DRBG *drbg, * to or if |prediction_resistance| is set. Additional input can be * sent in |adin| and |adinlen|. * + * Requires that drbg->lock is already locked for write, if non-null. + * * Returns 1 on success, 0 on failure. * */ @@ -386,11 +601,23 @@ int RAND_DRBG_generate(RAND_DRBG *drbg, unsigned char *out, size_t outlen, reseed_required = 1; } - if (drbg->reseed_counter >= drbg->reseed_interval) - reseed_required = 1; + if (drbg->reseed_interval > 0) { + if (drbg->generate_counter >= drbg->reseed_interval) + reseed_required = 1; + } + if (drbg->reseed_time_interval > 0) { + time_t now = time(NULL); + if (now < drbg->reseed_time + || now - drbg->reseed_time >= drbg->reseed_time_interval) + reseed_required = 1; + } + if (drbg->reseed_counter > 0 && drbg->parent != NULL) { + if (drbg->reseed_counter != drbg->parent->reseed_counter) + reseed_required = 1; + } if (reseed_required || prediction_resistance) { - if (!RAND_DRBG_reseed(drbg, adin, adinlen)) { + if (!RAND_DRBG_reseed(drbg, adin, adinlen, prediction_resistance)) { RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_RESEED_ERROR); return 0; } @@ -398,54 +625,58 @@ int RAND_DRBG_generate(RAND_DRBG *drbg, unsigned char *out, size_t outlen, adinlen = 0; } - if (!ctr_generate(drbg, out, outlen, adin, adinlen)) { + if (!drbg->meth->generate(drbg, out, outlen, adin, adinlen)) { drbg->state = DRBG_ERROR; RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_GENERATE_ERROR); return 0; } - drbg->reseed_counter++; + drbg->generate_counter++; return 1; } /* - * Set the RAND_DRBG callbacks for obtaining entropy and nonce. - * - * In the following, the signature and the semantics of the - * get_entropy() and cleanup_entropy() callbacks are explained. + * Generates |outlen| random bytes and stores them in |out|. It will + * using the given |drbg| to generate the bytes. * - * GET_ENTROPY + * Requires that drbg->lock is already locked for write, if non-null. * - * size_t get_entropy(RAND_DRBG *ctx, - * unsigned char **pout, - * int entropy, - * size_t min_len, size_t max_len); - * - * This is a request to allocate and fill a buffer of size - * |min_len| <= size <= |max_len| (in bytes) which contains - * at least |entropy| bits of randomness. The buffer's address is - * to be returned in |*pout| and the number of collected - * randomness bytes (which may be less than the allocated size - * of the buffer) as return value. - * - * If the callback fails to acquire at least |entropy| bits of - * randomness, it shall return a buffer length of 0. - * - * CLEANUP_ENTROPY - * - * void cleanup_entropy(RAND_DRBG *ctx, - * unsigned char *out, size_t outlen); - * - * A request to clear and free the buffer allocated by get_entropy(). - * The values |out| and |outlen| are expected to be the random buffer's - * address and length, as returned by the get_entropy() callback. + * Returns 1 on success 0 on failure. + */ +int RAND_DRBG_bytes(RAND_DRBG *drbg, unsigned char *out, size_t outlen) +{ + unsigned char *additional = NULL; + size_t additional_len; + size_t chunk; + size_t ret; + + additional_len = rand_drbg_get_additional_data(&additional, drbg->max_adinlen); + + for ( ; outlen > 0; outlen -= chunk, out += chunk) { + chunk = outlen; + if (chunk > drbg->max_request) + chunk = drbg->max_request; + ret = RAND_DRBG_generate(drbg, out, chunk, 0, additional, additional_len); + if (!ret) + goto err; + } + ret = 1; + +err: + if (additional_len != 0) + OPENSSL_secure_clear_free(additional, additional_len); + + return ret; +} + +/* + * Set the RAND_DRBG callbacks for obtaining entropy and nonce. * - * GET_NONCE, CLEANUP_NONCE + * Setting the callbacks is allowed only if the drbg has not been + * initialized yet. Otherwise, the operation will fail. * - * Signature and semantics of the get_nonce() and cleanup_nonce() - * callbacks are analogous to get_entropy() and cleanup_entropy(). - * Currently, the nonce is used only for the known answer tests. + * Returns 1 on success, 0 on failure. */ int RAND_DRBG_set_callbacks(RAND_DRBG *drbg, RAND_DRBG_get_entropy_fn get_entropy, @@ -464,15 +695,134 @@ int RAND_DRBG_set_callbacks(RAND_DRBG *drbg, /* * Set the reseed interval. + * + * The drbg will reseed automatically whenever the number of generate + * requests exceeds the given reseed interval. If the reseed interval + * is 0, then this feature is disabled. + * + * Returns 1 on success, 0 on failure. */ -int RAND_DRBG_set_reseed_interval(RAND_DRBG *drbg, int interval) +int RAND_DRBG_set_reseed_interval(RAND_DRBG *drbg, unsigned int interval) { - if (interval < 0 || interval > MAX_RESEED) + if (interval > MAX_RESEED_INTERVAL) return 0; drbg->reseed_interval = interval; return 1; } +/* + * Set the reseed time interval. + * + * The drbg will reseed automatically whenever the time elapsed since + * the last reseeding exceeds the given reseed time interval. For safety, + * a reseeding will also occur if the clock has been reset to a smaller + * value. + * + * Returns 1 on success, 0 on failure. + */ +int RAND_DRBG_set_reseed_time_interval(RAND_DRBG *drbg, time_t interval) +{ + if (interval > MAX_RESEED_TIME_INTERVAL) + return 0; + drbg->reseed_time_interval = interval; + return 1; +} + +/* + * Set the default values for reseed (time) intervals of new DRBG instances + * + * The default values can be set independently for master DRBG instances + * (without a parent) and slave DRBG instances (with parent). + * + * Returns 1 on success, 0 on failure. + */ + +int RAND_DRBG_set_reseed_defaults( + unsigned int _master_reseed_interval, + unsigned int _slave_reseed_interval, + time_t _master_reseed_time_interval, + time_t _slave_reseed_time_interval + ) +{ + if (_master_reseed_interval > MAX_RESEED_INTERVAL + || _slave_reseed_interval > MAX_RESEED_INTERVAL) + return 0; + + if (_master_reseed_time_interval > MAX_RESEED_TIME_INTERVAL + || _slave_reseed_time_interval > MAX_RESEED_TIME_INTERVAL) + return 0; + + master_reseed_interval = _master_reseed_interval; + slave_reseed_interval = _slave_reseed_interval; + + master_reseed_time_interval = _master_reseed_time_interval; + slave_reseed_time_interval = _slave_reseed_time_interval; + + return 1; +} + +/* + * Locks the given drbg. Locking a drbg which does not have locking + * enabled is considered a successful no-op. + * + * Returns 1 on success, 0 on failure. + */ +int rand_drbg_lock(RAND_DRBG *drbg) +{ + if (drbg->lock != NULL) + return CRYPTO_THREAD_write_lock(drbg->lock); + + return 1; +} + +/* + * Unlocks the given drbg. Unlocking a drbg which does not have locking + * enabled is considered a successful no-op. + * + * Returns 1 on success, 0 on failure. + */ +int rand_drbg_unlock(RAND_DRBG *drbg) +{ + if (drbg->lock != NULL) + return CRYPTO_THREAD_unlock(drbg->lock); + + return 1; +} + +/* + * Enables locking for the given drbg + * + * Locking can only be enabled if the random generator + * is in the uninitialized state. + * + * Returns 1 on success, 0 on failure. + */ +int rand_drbg_enable_locking(RAND_DRBG *drbg) +{ + if (drbg->state != DRBG_UNINITIALISED) { + RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING, + RAND_R_DRBG_ALREADY_INITIALIZED); + return 0; + } + + if (drbg->lock == NULL) { + if (drbg->parent != NULL && drbg->parent->lock == NULL) { + RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING, + RAND_R_PARENT_LOCKING_NOT_ENABLED); + return 0; + } + + drbg->lock = CRYPTO_THREAD_lock_new(); + if (drbg->lock == NULL) { + RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING, + RAND_R_FAILED_TO_CREATE_LOCK); + return 0; + } + } + + return 1; +} + /* * Get and set the EXDATA */ @@ -493,31 +843,26 @@ void *RAND_DRBG_get_ex_data(const RAND_DRBG *drbg, int idx) */ /* - * Initializes the DRBG with default settings. - * For global DRBGs a global lock is created with the given name - * Returns 1 on success, 0 on failure + * Allocates a new global DRBG on the secure heap (if enabled) and + * initializes it with default settings. + * + * Returns a pointer to the new DRBG instance on success, NULL on failure. */ -static int drbg_setup(RAND_DRBG *drbg, const char *name) +static RAND_DRBG *drbg_setup(RAND_DRBG *parent) { - int ret = 1; + RAND_DRBG *drbg; - if (name != NULL) { - if (drbg->lock != NULL) { - RANDerr(RAND_F_DRBG_SETUP, ERR_R_INTERNAL_ERROR); - return 0; - } + drbg = RAND_DRBG_secure_new(rand_drbg_type, rand_drbg_flags, parent); + if (drbg == NULL) + return NULL; - drbg->lock = CRYPTO_THREAD_glock_new(name); - if (drbg->lock == NULL) { - RANDerr(RAND_F_DRBG_SETUP, RAND_R_FAILED_TO_CREATE_LOCK); - return 0; - } - } + /* Only the master DRBG needs to have a lock */ + if (parent == NULL && rand_drbg_enable_locking(drbg) == 0) + goto err; + + /* enable seed propagation */ + drbg->reseed_counter = 1; - ret &= RAND_DRBG_set(drbg, - RAND_DRBG_NID, RAND_DRBG_FLAG_CTR_USE_DF) == 1; - ret &= RAND_DRBG_set_callbacks(drbg, rand_drbg_get_entropy, - rand_drbg_cleanup_entropy, NULL, NULL) == 1; /* * Ignore instantiation error so support just-in-time instantiation. * @@ -527,7 +872,11 @@ static int drbg_setup(RAND_DRBG *drbg, const char *name) RAND_DRBG_instantiate(drbg, (const unsigned char *) ossl_pers_string, sizeof(ossl_pers_string) - 1); - return ret; + return drbg; + +err: + RAND_DRBG_free(drbg); + return NULL; } /* @@ -538,52 +887,58 @@ DEFINE_RUN_ONCE_STATIC(do_rand_drbg_init) { int ret = 1; - ret &= drbg_setup(&rand_drbg, "rand_drbg"); - ret &= drbg_setup(&priv_drbg, "priv_drbg"); + /* + * ensure that libcrypto is initialized, otherwise the + * DRBG locks are not cleaned up properly + */ + if (!OPENSSL_init_crypto(0, NULL)) + return 0; - return ret; -} + ossl_init_thread_start(OPENSSL_INIT_THREAD_RAND); -/* Cleans up the given global DRBG */ -static void drbg_cleanup(RAND_DRBG *drbg) -{ - CRYPTO_THREAD_lock_free(drbg->lock); - RAND_DRBG_uninstantiate(drbg); + master_drbg = drbg_setup(NULL); + + ret &= CRYPTO_THREAD_init_local(&private_drbg, NULL); + ret &= CRYPTO_THREAD_init_local(&public_drbg, NULL); + + if (master_drbg == NULL || ret == 0) + return 0; + + return 1; } /* Clean up the global DRBGs before exit */ void rand_drbg_cleanup_int(void) { - drbg_cleanup(&rand_drbg); - drbg_cleanup(&priv_drbg); + RAND_DRBG_free(master_drbg); + master_drbg = NULL; + + CRYPTO_THREAD_cleanup_local(&private_drbg); + CRYPTO_THREAD_cleanup_local(&public_drbg); +} + +void drbg_delete_thread_state() +{ + RAND_DRBG *drbg; + + drbg = CRYPTO_THREAD_get_local(&public_drbg); + RAND_DRBG_free(drbg); + + drbg = CRYPTO_THREAD_get_local(&private_drbg); + RAND_DRBG_free(drbg); } /* Implements the default OpenSSL RAND_bytes() method */ static int drbg_bytes(unsigned char *out, int count) { - int ret = 0; - size_t chunk; - RAND_DRBG *drbg = RAND_DRBG_get0_global(); + int ret; + RAND_DRBG *drbg = RAND_DRBG_get0_public(); if (drbg == NULL) return 0; - CRYPTO_THREAD_write_lock(drbg->lock); - if (drbg->state == DRBG_UNINITIALISED) - goto err; - - for ( ; count > 0; count -= chunk, out += chunk) { - chunk = count; - if (chunk > drbg->max_request) - chunk = drbg->max_request; - ret = RAND_DRBG_generate(drbg, out, chunk, 0, NULL, 0); - if (!ret) - goto err; - } - ret = 1; + ret = RAND_DRBG_bytes(drbg, out, count); -err: - CRYPTO_THREAD_unlock(drbg->lock); return ret; } @@ -591,7 +946,7 @@ err: static int drbg_add(const void *buf, int num, double randomness) { int ret = 0; - RAND_DRBG *drbg = RAND_DRBG_get0_global(); + RAND_DRBG *drbg = RAND_DRBG_get0_master(); if (drbg == NULL) return 0; @@ -609,11 +964,11 @@ static int drbg_add(const void *buf, int num, double randomness) return 0; } - CRYPTO_THREAD_write_lock(drbg->lock); + rand_drbg_lock(drbg); ret = rand_drbg_restart(drbg, buf, (size_t)(unsigned int)num, (size_t)(8*randomness)); - CRYPTO_THREAD_unlock(drbg->lock); + rand_drbg_unlock(drbg); return ret; } @@ -628,39 +983,68 @@ static int drbg_seed(const void *buf, int num) static int drbg_status(void) { int ret; - RAND_DRBG *drbg = RAND_DRBG_get0_global(); + RAND_DRBG *drbg = RAND_DRBG_get0_master(); if (drbg == NULL) return 0; - CRYPTO_THREAD_write_lock(drbg->lock); + rand_drbg_lock(drbg); ret = drbg->state == DRBG_READY ? 1 : 0; - CRYPTO_THREAD_unlock(drbg->lock); + rand_drbg_unlock(drbg); return ret; } /* - * Get the global public DRBG. + * Get the master DRBG. * Returns pointer to the DRBG on success, NULL on failure. + * */ -RAND_DRBG *RAND_DRBG_get0_global(void) +RAND_DRBG *RAND_DRBG_get0_master(void) { if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init)) return NULL; - return &rand_drbg; + return master_drbg; } /* - * Get the global private DRBG. + * Get the public DRBG. * Returns pointer to the DRBG on success, NULL on failure. */ -RAND_DRBG *RAND_DRBG_get0_priv_global(void) +RAND_DRBG *RAND_DRBG_get0_public(void) { + RAND_DRBG *drbg; + if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init)) return NULL; - return &priv_drbg; + drbg = CRYPTO_THREAD_get_local(&public_drbg); + if (drbg == NULL) { + ossl_init_thread_start(OPENSSL_INIT_THREAD_RAND); + drbg = drbg_setup(master_drbg); + CRYPTO_THREAD_set_local(&public_drbg, drbg); + } + return drbg; +} + +/* + * Get the private DRBG. + * Returns pointer to the DRBG on success, NULL on failure. + */ +RAND_DRBG *RAND_DRBG_get0_private(void) +{ + RAND_DRBG *drbg; + + if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init)) + return NULL; + + drbg = CRYPTO_THREAD_get_local(&private_drbg); + if (drbg == NULL) { + ossl_init_thread_start(OPENSSL_INIT_THREAD_RAND); + drbg = drbg_setup(master_drbg); + CRYPTO_THREAD_set_local(&private_drbg, drbg); + } + return drbg; } RAND_METHOD rand_meth = {