2139145b72
The drbg's lock must be held across calls to RAND_DRBG_generate() to prevent simultaneous modification of internal state. This was observed in practice with simultaneous SSL_new() calls attempting to seed the (separate) per-SSL RAND_DRBG instances from the global rand_drbg instance; this eventually led to simultaneous calls to ctr_BCC_update() attempting to increment drbg->bltmp_pos for their respective partial final block, violating the invariant that bltmp_pos < 16. The AES operations performed in ctr_BCC_blocks() makes the race window quite easy to trigger. A value of bltmp_pos greater than 16 induces catastrophic failure in ctr_BCC_final(), with subtraction overflowing and leading to an attempt to memset() to zero a very large range, which eventually reaches an unmapped page and segfaults. Provide the needed locking in get_entropy_from_parent(), as well as fixing a similar issue in RAND_priv_bytes(). There is also an unlocked call to RAND_DRBG_generate() in ssl_randbytes(), but the requisite serialization is already guaranteed by the requirements on the application's usage of SSL objects, and no further locking is needed for correct behavior. In that case, leave a comment noting the apparent discrepancy and the reason for its safety (at present). Reviewed-by: Paul Dale <paul.dale@oracle.com> Reviewed-by: Kurt Roeckx <kurt@roeckx.be> Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/4328)
686 lines
20 KiB
C
686 lines
20 KiB
C
/*
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* Copyright 2011-2017 The OpenSSL Project Authors. All Rights Reserved.
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*
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* Licensed under the OpenSSL license (the "License"). You may not use
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* this file except in compliance with the License. You can obtain a copy
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* in the file LICENSE in the source distribution or at
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* https://www.openssl.org/source/license.html
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*/
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#include <string.h>
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#include <openssl/crypto.h>
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#include <openssl/err.h>
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#include <openssl/rand.h>
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#include "rand_lcl.h"
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#include "internal/thread_once.h"
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#include "internal/rand_int.h"
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static RAND_DRBG rand_drbg; /* The default global DRBG. */
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static RAND_DRBG priv_drbg; /* The global private-key DRBG. */
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/* NIST SP 800-90A DRBG recommends the use of a personalization string. */
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static const char ossl_pers_string[] = "OpenSSL NIST SP 800-90A DRBG";
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/*
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* Support framework for NIST SP 800-90A DRBG, AES-CTR mode.
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* The RAND_DRBG is OpenSSL's pointer to an instance of the DRBG.
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*
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* The OpenSSL model is to have new and free functions, and that new
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* does all initialization. That is not the NIST model, which has
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* instantiation and un-instantiate, and re-use within a new/free
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* lifecycle. (No doubt this comes from the desire to support hardware
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* DRBG, where allocation of resources on something like an HSM is
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* a much bigger deal than just re-setting an allocated resource.)
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*/
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static CRYPTO_ONCE rand_drbg_init = CRYPTO_ONCE_STATIC_INIT;
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static int drbg_setup(RAND_DRBG *drbg, const char *name);
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/*
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* Set/initialize |drbg| to be of type |nid|, with optional |flags|.
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* Return -2 if the type is not supported, 1 on success and -1 on
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* failure.
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*/
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int RAND_DRBG_set(RAND_DRBG *drbg, int nid, unsigned int flags)
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{
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int ret = 1;
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drbg->state = DRBG_UNINITIALISED;
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drbg->flags = flags;
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drbg->nid = nid;
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switch (nid) {
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default:
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RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_UNSUPPORTED_DRBG_TYPE);
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return -2;
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case 0:
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/* Uninitialized; that's okay. */
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return 1;
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case NID_aes_128_ctr:
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case NID_aes_192_ctr:
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case NID_aes_256_ctr:
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ret = ctr_init(drbg);
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break;
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}
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if (ret < 0)
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RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_ERROR_INITIALISING_DRBG);
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return ret;
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}
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/*
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* Allocate memory and initialize a new DRBG. The |parent|, if not
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* NULL, will be used to auto-seed this RAND_DRBG as needed.
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*/
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RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent)
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{
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RAND_DRBG *drbg = OPENSSL_zalloc(sizeof(*drbg));
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if (drbg == NULL) {
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RANDerr(RAND_F_RAND_DRBG_NEW, ERR_R_MALLOC_FAILURE);
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goto err;
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}
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drbg->fork_count = rand_fork_count;
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drbg->parent = parent;
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if (RAND_DRBG_set(drbg, type, flags) < 0)
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goto err;
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if (parent != NULL) {
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if (!RAND_DRBG_set_callbacks(drbg, rand_drbg_get_entropy,
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rand_drbg_cleanup_entropy,
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NULL, NULL))
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goto err;
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}
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return drbg;
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err:
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OPENSSL_free(drbg);
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return NULL;
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}
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/*
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* Uninstantiate |drbg| and free all memory.
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*/
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void RAND_DRBG_free(RAND_DRBG *drbg)
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{
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if (drbg == NULL)
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return;
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ctr_uninstantiate(drbg);
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CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DRBG, drbg, &drbg->ex_data);
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OPENSSL_clear_free(drbg, sizeof(*drbg));
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}
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/*
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* Instantiate |drbg|, after it has been initialized. Use |pers| and
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* |perslen| as prediction-resistance input.
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*
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* Requires that drbg->lock is already locked for write, if non-null.
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*/
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int RAND_DRBG_instantiate(RAND_DRBG *drbg,
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const unsigned char *pers, size_t perslen)
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{
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unsigned char *nonce = NULL, *entropy = NULL;
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size_t noncelen = 0, entropylen = 0;
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if (perslen > drbg->max_perslen) {
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RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
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RAND_R_PERSONALISATION_STRING_TOO_LONG);
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goto end;
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}
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if (drbg->state != DRBG_UNINITIALISED) {
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RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
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drbg->state == DRBG_ERROR ? RAND_R_IN_ERROR_STATE
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: RAND_R_ALREADY_INSTANTIATED);
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goto end;
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}
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drbg->state = DRBG_ERROR;
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if (drbg->get_entropy != NULL)
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entropylen = drbg->get_entropy(drbg, &entropy, drbg->strength,
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drbg->min_entropylen, drbg->max_entropylen);
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if (entropylen < drbg->min_entropylen
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|| entropylen > drbg->max_entropylen) {
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RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_RETRIEVING_ENTROPY);
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goto end;
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}
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if (drbg->max_noncelen > 0 && drbg->get_nonce != NULL) {
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noncelen = drbg->get_nonce(drbg, &nonce, drbg->strength / 2,
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drbg->min_noncelen, drbg->max_noncelen);
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if (noncelen < drbg->min_noncelen || noncelen > drbg->max_noncelen) {
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RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
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RAND_R_ERROR_RETRIEVING_NONCE);
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goto end;
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}
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}
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if (!ctr_instantiate(drbg, entropy, entropylen,
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nonce, noncelen, pers, perslen)) {
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RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_INSTANTIATING_DRBG);
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goto end;
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}
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drbg->state = DRBG_READY;
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drbg->reseed_counter = 1;
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end:
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if (entropy != NULL && drbg->cleanup_entropy != NULL)
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drbg->cleanup_entropy(drbg, entropy, entropylen);
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if (nonce != NULL && drbg->cleanup_nonce!= NULL )
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drbg->cleanup_nonce(drbg, nonce, noncelen);
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if (drbg->pool != NULL) {
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if (drbg->state == DRBG_READY) {
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RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
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RAND_R_ERROR_ENTROPY_POOL_WAS_IGNORED);
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drbg->state = DRBG_ERROR;
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}
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RAND_POOL_free(drbg->pool);
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drbg->pool = NULL;
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}
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if (drbg->state == DRBG_READY)
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return 1;
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return 0;
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}
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/*
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* Uninstantiate |drbg|. Must be instantiated before it can be used.
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*
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* Requires that drbg->lock is already locked for write, if non-null.
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*/
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int RAND_DRBG_uninstantiate(RAND_DRBG *drbg)
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{
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int ret = ctr_uninstantiate(drbg);
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OPENSSL_cleanse(&drbg->ctr, sizeof(drbg->ctr));
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drbg->state = DRBG_UNINITIALISED;
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return ret;
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}
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/*
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* Reseed |drbg|, mixing in the specified data
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*
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* Requires that drbg->lock is already locked for write, if non-null.
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*/
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int RAND_DRBG_reseed(RAND_DRBG *drbg,
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const unsigned char *adin, size_t adinlen)
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{
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unsigned char *entropy = NULL;
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size_t entropylen = 0;
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if (drbg->state == DRBG_ERROR) {
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RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_IN_ERROR_STATE);
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return 0;
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}
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if (drbg->state == DRBG_UNINITIALISED) {
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RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_NOT_INSTANTIATED);
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return 0;
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}
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if (adin == NULL)
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adinlen = 0;
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else if (adinlen > drbg->max_adinlen) {
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RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_ADDITIONAL_INPUT_TOO_LONG);
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return 0;
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}
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drbg->state = DRBG_ERROR;
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if (drbg->get_entropy != NULL)
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entropylen = drbg->get_entropy(drbg, &entropy, drbg->strength,
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drbg->min_entropylen, drbg->max_entropylen);
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if (entropylen < drbg->min_entropylen
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|| entropylen > drbg->max_entropylen) {
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RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_ERROR_RETRIEVING_ENTROPY);
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goto end;
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}
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if (!ctr_reseed(drbg, entropy, entropylen, adin, adinlen))
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goto end;
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drbg->state = DRBG_READY;
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drbg->reseed_counter = 1;
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end:
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if (entropy != NULL && drbg->cleanup_entropy != NULL)
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drbg->cleanup_entropy(drbg, entropy, entropylen);
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if (drbg->state == DRBG_READY)
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return 1;
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return 0;
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}
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/*
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* Restart |drbg|, using the specified entropy or additional input
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*
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* Tries its best to get the drbg instantiated by all means,
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* regardless of its current state.
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*
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* Optionally, a |buffer| of |len| random bytes can be passed,
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* which is assumed to contain at least |entropy| bits of entropy.
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*
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* If |entropy| > 0, the buffer content is used as entropy input.
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*
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* If |entropy| == 0, the buffer content is used as additional input
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*
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* Returns 1 on success, 0 on failure.
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*
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* This function is used internally only.
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*/
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int rand_drbg_restart(RAND_DRBG *drbg,
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const unsigned char *buffer, size_t len, size_t entropy)
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{
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int reseeded = 0;
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const unsigned char *adin = NULL;
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size_t adinlen = 0;
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if (drbg->pool != NULL) {
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RANDerr(RAND_F_RAND_DRBG_RESTART, ERR_R_INTERNAL_ERROR);
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RAND_POOL_free(drbg->pool);
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drbg->pool = NULL;
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}
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if (buffer != NULL) {
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if (entropy > 0) {
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if (drbg->max_entropylen < len) {
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RANDerr(RAND_F_RAND_DRBG_RESTART,
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RAND_R_ENTROPY_INPUT_TOO_LONG);
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return 0;
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}
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if (entropy > 8 * len) {
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RANDerr(RAND_F_RAND_DRBG_RESTART, RAND_R_ENTROPY_OUT_OF_RANGE);
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return 0;
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}
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/* will be picked up by the rand_drbg_get_entropy() callback */
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drbg->pool = RAND_POOL_new(entropy, len, len);
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if (drbg->pool == NULL)
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return 0;
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RAND_POOL_add(drbg->pool, buffer, len, entropy);
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} else {
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if (drbg->max_adinlen < len) {
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RANDerr(RAND_F_RAND_DRBG_RESTART,
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RAND_R_ADDITIONAL_INPUT_TOO_LONG);
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return 0;
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}
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adin = buffer;
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adinlen = len;
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}
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}
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/* repair error state */
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if (drbg->state == DRBG_ERROR)
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RAND_DRBG_uninstantiate(drbg);
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/* repair uninitialized state */
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if (drbg->state == DRBG_UNINITIALISED) {
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drbg_setup(drbg, NULL);
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/* already reseeded. prevent second reseeding below */
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reseeded = (drbg->state == DRBG_READY);
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}
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/* refresh current state if entropy or additional input has been provided */
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if (drbg->state == DRBG_READY) {
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if (adin != NULL) {
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/*
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* mix in additional input without reseeding
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*
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* Similar to RAND_DRBG_reseed(), but the provided additional
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* data |adin| is mixed into the current state without pulling
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* entropy from the trusted entropy source using get_entropy().
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* This is not a reseeding in the strict sense of NIST SP 800-90A.
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*/
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ctr_reseed(drbg, adin, adinlen, NULL, 0);
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} else if (reseeded == 0) {
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/* do a full reseeding if it has not been done yet above */
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RAND_DRBG_reseed(drbg, NULL, 0);
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}
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}
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/* check whether a given entropy pool was cleared properly during reseed */
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if (drbg->pool != NULL) {
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drbg->state = DRBG_ERROR;
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RANDerr(RAND_F_RAND_DRBG_RESTART, ERR_R_INTERNAL_ERROR);
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RAND_POOL_free(drbg->pool);
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drbg->pool = NULL;
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return 0;
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}
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return drbg->state == DRBG_READY;
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}
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/*
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* Generate |outlen| bytes into the buffer at |out|. Reseed if we need
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* to or if |prediction_resistance| is set. Additional input can be
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* sent in |adin| and |adinlen|.
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*
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* Requires that drbg->lock is already locked for write, if non-null.
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*
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* Returns 1 on success, 0 on failure.
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*
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*/
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int RAND_DRBG_generate(RAND_DRBG *drbg, unsigned char *out, size_t outlen,
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int prediction_resistance,
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const unsigned char *adin, size_t adinlen)
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{
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int reseed_required = 0;
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if (drbg->state != DRBG_READY) {
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/* try to recover from previous errors */
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rand_drbg_restart(drbg, NULL, 0, 0);
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if (drbg->state == DRBG_ERROR) {
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RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_IN_ERROR_STATE);
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return 0;
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}
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if (drbg->state == DRBG_UNINITIALISED) {
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RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_NOT_INSTANTIATED);
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return 0;
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}
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}
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if (outlen > drbg->max_request) {
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RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_REQUEST_TOO_LARGE_FOR_DRBG);
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return 0;
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}
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if (adinlen > drbg->max_adinlen) {
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RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_ADDITIONAL_INPUT_TOO_LONG);
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return 0;
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}
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if (drbg->fork_count != rand_fork_count) {
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drbg->fork_count = rand_fork_count;
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reseed_required = 1;
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}
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if (drbg->reseed_counter >= drbg->reseed_interval)
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reseed_required = 1;
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if (reseed_required || prediction_resistance) {
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if (!RAND_DRBG_reseed(drbg, adin, adinlen)) {
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RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_RESEED_ERROR);
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return 0;
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}
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adin = NULL;
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adinlen = 0;
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}
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if (!ctr_generate(drbg, out, outlen, adin, adinlen)) {
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drbg->state = DRBG_ERROR;
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RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_GENERATE_ERROR);
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return 0;
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}
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drbg->reseed_counter++;
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return 1;
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}
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/*
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* Set the RAND_DRBG callbacks for obtaining entropy and nonce.
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*
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* In the following, the signature and the semantics of the
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* get_entropy() and cleanup_entropy() callbacks are explained.
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*
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* GET_ENTROPY
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*
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* size_t get_entropy(RAND_DRBG *ctx,
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* unsigned char **pout,
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* int entropy,
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* size_t min_len, size_t max_len);
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*
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* This is a request to allocate and fill a buffer of size
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* |min_len| <= size <= |max_len| (in bytes) which contains
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* at least |entropy| bits of randomness. The buffer's address is
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* to be returned in |*pout| and the number of collected
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* randomness bytes (which may be less than the allocated size
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* of the buffer) as return value.
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*
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* If the callback fails to acquire at least |entropy| bits of
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* randomness, it shall return a buffer length of 0.
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*
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* CLEANUP_ENTROPY
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*
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* void cleanup_entropy(RAND_DRBG *ctx,
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* unsigned char *out, size_t outlen);
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*
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* A request to clear and free the buffer allocated by get_entropy().
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* The values |out| and |outlen| are expected to be the random buffer's
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* address and length, as returned by the get_entropy() callback.
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*
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* GET_NONCE, CLEANUP_NONCE
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*
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* Signature and semantics of the get_nonce() and cleanup_nonce()
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* callbacks are analogous to get_entropy() and cleanup_entropy().
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* Currently, the nonce is used only for the known answer tests.
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*/
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int RAND_DRBG_set_callbacks(RAND_DRBG *drbg,
|
|
RAND_DRBG_get_entropy_fn get_entropy,
|
|
RAND_DRBG_cleanup_entropy_fn cleanup_entropy,
|
|
RAND_DRBG_get_nonce_fn get_nonce,
|
|
RAND_DRBG_cleanup_nonce_fn cleanup_nonce)
|
|
{
|
|
if (drbg->state != DRBG_UNINITIALISED)
|
|
return 0;
|
|
drbg->get_entropy = get_entropy;
|
|
drbg->cleanup_entropy = cleanup_entropy;
|
|
drbg->get_nonce = get_nonce;
|
|
drbg->cleanup_nonce = cleanup_nonce;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Set the reseed interval.
|
|
*/
|
|
int RAND_DRBG_set_reseed_interval(RAND_DRBG *drbg, int interval)
|
|
{
|
|
if (interval < 0 || interval > MAX_RESEED)
|
|
return 0;
|
|
drbg->reseed_interval = interval;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Get and set the EXDATA
|
|
*/
|
|
int RAND_DRBG_set_ex_data(RAND_DRBG *drbg, int idx, void *arg)
|
|
{
|
|
return CRYPTO_set_ex_data(&drbg->ex_data, idx, arg);
|
|
}
|
|
|
|
void *RAND_DRBG_get_ex_data(const RAND_DRBG *drbg, int idx)
|
|
{
|
|
return CRYPTO_get_ex_data(&drbg->ex_data, idx);
|
|
}
|
|
|
|
|
|
/*
|
|
* The following functions provide a RAND_METHOD that works on the
|
|
* global DRBG. They lock.
|
|
*/
|
|
|
|
/*
|
|
* 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
|
|
*/
|
|
static int drbg_setup(RAND_DRBG *drbg, const char *name)
|
|
{
|
|
int ret = 1;
|
|
|
|
if (name != NULL) {
|
|
if (drbg->lock != NULL) {
|
|
RANDerr(RAND_F_DRBG_SETUP, ERR_R_INTERNAL_ERROR);
|
|
return 0;
|
|
}
|
|
|
|
drbg->lock = CRYPTO_THREAD_glock_new(name);
|
|
if (drbg->lock == NULL) {
|
|
RANDerr(RAND_F_DRBG_SETUP, RAND_R_FAILED_TO_CREATE_LOCK);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
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.
|
|
*
|
|
* The state of the drbg will be checked in RAND_DRBG_generate() and
|
|
* an automatic recovery is attempted.
|
|
*/
|
|
RAND_DRBG_instantiate(drbg,
|
|
(const unsigned char *) ossl_pers_string,
|
|
sizeof(ossl_pers_string) - 1);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Initialize the global DRBGs on first use.
|
|
* Returns 1 on success, 0 on failure.
|
|
*/
|
|
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");
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Cleans up the given global DRBG */
|
|
static void drbg_cleanup(RAND_DRBG *drbg)
|
|
{
|
|
CRYPTO_THREAD_lock_free(drbg->lock);
|
|
RAND_DRBG_uninstantiate(drbg);
|
|
}
|
|
|
|
/* Clean up the global DRBGs before exit */
|
|
void rand_drbg_cleanup_int(void)
|
|
{
|
|
drbg_cleanup(&rand_drbg);
|
|
drbg_cleanup(&priv_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();
|
|
|
|
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;
|
|
|
|
err:
|
|
CRYPTO_THREAD_unlock(drbg->lock);
|
|
return ret;
|
|
}
|
|
|
|
/* Implements the default OpenSSL RAND_add() method */
|
|
static int drbg_add(const void *buf, int num, double randomness)
|
|
{
|
|
int ret = 0;
|
|
RAND_DRBG *drbg = RAND_DRBG_get0_global();
|
|
|
|
if (drbg == NULL)
|
|
return 0;
|
|
|
|
if (num < 0 || randomness < 0.0)
|
|
return 0;
|
|
|
|
if (randomness > (double)drbg->max_entropylen) {
|
|
/*
|
|
* The purpose of this check is to bound |randomness| by a
|
|
* relatively small value in order to prevent an integer
|
|
* overflow when multiplying by 8 in the rand_drbg_restart()
|
|
* call below.
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
CRYPTO_THREAD_write_lock(drbg->lock);
|
|
ret = rand_drbg_restart(drbg, buf,
|
|
(size_t)(unsigned int)num,
|
|
(size_t)(8*randomness));
|
|
CRYPTO_THREAD_unlock(drbg->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Implements the default OpenSSL RAND_seed() method */
|
|
static int drbg_seed(const void *buf, int num)
|
|
{
|
|
return drbg_add(buf, num, num);
|
|
}
|
|
|
|
/* Implements the default OpenSSL RAND_status() method */
|
|
static int drbg_status(void)
|
|
{
|
|
int ret;
|
|
RAND_DRBG *drbg = RAND_DRBG_get0_global();
|
|
|
|
if (drbg == NULL)
|
|
return 0;
|
|
|
|
CRYPTO_THREAD_write_lock(drbg->lock);
|
|
ret = drbg->state == DRBG_READY ? 1 : 0;
|
|
CRYPTO_THREAD_unlock(drbg->lock);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Get the global public DRBG.
|
|
* Returns pointer to the DRBG on success, NULL on failure.
|
|
*/
|
|
RAND_DRBG *RAND_DRBG_get0_global(void)
|
|
{
|
|
if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
|
|
return NULL;
|
|
|
|
return &rand_drbg;
|
|
}
|
|
|
|
/*
|
|
* Get the global private DRBG.
|
|
* Returns pointer to the DRBG on success, NULL on failure.
|
|
*/
|
|
RAND_DRBG *RAND_DRBG_get0_priv_global(void)
|
|
{
|
|
if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
|
|
return NULL;
|
|
|
|
return &priv_drbg;
|
|
}
|
|
|
|
RAND_METHOD rand_meth = {
|
|
drbg_seed,
|
|
drbg_bytes,
|
|
NULL,
|
|
drbg_add,
|
|
drbg_bytes,
|
|
drbg_status
|
|
};
|
|
|
|
RAND_METHOD *RAND_OpenSSL(void)
|
|
{
|
|
return &rand_meth;
|
|
}
|