Commit 4f9dabbf authored by Dr. Matthias St. Pierre's avatar Dr. Matthias St. Pierre
Browse files

DRBG: unify initialization and cleanup code 



The functions drbg_setup() and drbg_cleanup() used to duplicate a lot of
code from RAND_DRBG_new() and RAND_DRBG_free(). This duplication has been
removed, which simplifies drbg_setup() and makes drbg_cleanup() obsolete.

Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5294)
parent 3ce1c27b

crypto/rand/drbg_lib.c

+44 −35
Original line number Diff line number Diff line
@@ -114,7 +114,11 @@ static const char ossl_pers_string[] = "OpenSSL NIST SP 800-90A DRBG"; 
static CRYPTO_ONCE rand_drbg_init = CRYPTO_ONCE_STATIC_INIT;



static RAND_DRBG *drbg_setup(RAND_DRBG *parent);

static void drbg_cleanup(RAND_DRBG *drbg);



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|.
@@ -149,19 +153,26 @@ int RAND_DRBG_set(RAND_DRBG *drbg, int nid, unsigned int flags) 
}



/*

 * Allocate memory and initialize a new DRBG.  The |parent|, if not

 * NULL, will be used to auto-seed this RAND_DRBG as needed.

 * 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.

 */

RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent)

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;

    }



    drbg->secure = secure && CRYPTO_secure_allocated(drbg);

    drbg->fork_count = rand_fork_count;

    drbg->parent = parent;

    if (RAND_DRBG_set(drbg, type, flags) == 0)
@@ -175,10 +186,24 @@ RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent) 
    return drbg;



err:

    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.

 */
@@ -189,7 +214,12 @@ void RAND_DRBG_free(RAND_DRBG *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);



    if (drbg->secure)

        OPENSSL_secure_clear_free(drbg, sizeof(*drbg));

    else

        OPENSSL_clear_free(drbg, sizeof(*drbg));

}
@@ -717,7 +747,7 @@ int RAND_DRBG_enable_locking(RAND_DRBG *drbg) 
    }



    if (drbg->lock == NULL) {

        if (drbg->parent != NULL && 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;
@@ -763,28 +793,17 @@ static RAND_DRBG *drbg_setup(RAND_DRBG *parent) 
{

    RAND_DRBG *drbg;



    drbg = OPENSSL_secure_zalloc(sizeof(RAND_DRBG));

    drbg = RAND_DRBG_secure_new(RAND_DRBG_NID, RAND_DRBG_FLAG_CTR_USE_DF, parent);

    if (drbg == NULL)

        return NULL;



    drbg->lock = CRYPTO_THREAD_lock_new();

    if (drbg->lock == NULL) {

        RANDerr(RAND_F_DRBG_SETUP, RAND_R_FAILED_TO_CREATE_LOCK);

        goto err;

    }



    if (RAND_DRBG_set(drbg,

                      RAND_DRBG_NID, RAND_DRBG_FLAG_CTR_USE_DF) != 1)

        goto err;

    if (RAND_DRBG_set_callbacks(drbg, rand_drbg_get_entropy,

                                rand_drbg_cleanup_entropy, NULL, NULL) != 1)

    if (RAND_DRBG_enable_locking(drbg) == 0)

        goto err;



    if (parent == NULL) {

        drbg->reseed_interval = MASTER_RESEED_INTERVAL;

        drbg->reseed_time_interval = MASTER_RESEED_TIME_INTERVAL;

    } else {

        drbg->parent = parent;

        drbg->reseed_interval = SLAVE_RESEED_INTERVAL;

        drbg->reseed_time_interval = SLAVE_RESEED_TIME_INTERVAL;

    }
@@ -804,7 +823,7 @@ static RAND_DRBG *drbg_setup(RAND_DRBG *parent) 
    return drbg;



err:

    drbg_cleanup(drbg);

    RAND_DRBG_free(drbg);

    return NULL;

}
@@ -831,22 +850,12 @@ DEFINE_RUN_ONCE_STATIC(do_rand_drbg_init) 
    return 1;

}



/* Cleans up the given global DRBG  */

static void drbg_cleanup(RAND_DRBG *drbg)

{

    if (drbg != NULL) {

        RAND_DRBG_uninstantiate(drbg);

        CRYPTO_THREAD_lock_free(drbg->lock);

        OPENSSL_secure_clear_free(drbg, sizeof(RAND_DRBG));

    }

}



/* Clean up the global DRBGs before exit */

void rand_drbg_cleanup_int(void)

{

    drbg_cleanup(drbg_private);

    drbg_cleanup(drbg_public);

    drbg_cleanup(drbg_master);

    RAND_DRBG_free(drbg_private);

    RAND_DRBG_free(drbg_public);

    RAND_DRBG_free(drbg_master);



    drbg_private = drbg_public = drbg_master = NULL;

}

crypto/rand/rand_lcl.h

+1 −0
Original line number Diff line number Diff line
@@ -115,6 +115,7 @@ typedef struct rand_drbg_ctr_st { 
struct rand_drbg_st {

    CRYPTO_RWLOCK *lock;

    RAND_DRBG *parent;

    int secure; /* 1: allocated on the secure heap, 0: otherwise */

    int nid; /* the underlying algorithm */

    int fork_count;

    unsigned short flags; /* various external flags */

include/internal/rand.h

+1 −0
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ 
 * Object lifetime functions.

 */

RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent);

RAND_DRBG *RAND_DRBG_secure_new(int type, unsigned int flags, RAND_DRBG *parent);

int RAND_DRBG_set(RAND_DRBG *drbg, int type, unsigned int flags);

int RAND_DRBG_instantiate(RAND_DRBG *drbg,

                          const unsigned char *pers, size_t perslen);

util/libcrypto.num

+1 −0
Original line number Diff line number Diff line
@@ -4504,3 +4504,4 @@ RAND_DRBG_bytes 4445 1_1_1 EXIST::FUNCTION: 
RAND_DRBG_lock                          4446	1_1_1	EXIST::FUNCTION:

RAND_DRBG_unlock                        4447	1_1_1	EXIST::FUNCTION:

RAND_DRBG_enable_locking                4448	1_1_1	EXIST::FUNCTION:

RAND_DRBG_secure_new                    4449	1_1_1	EXIST::FUNCTION: