Commit 812b1537 authored by Dr. Matthias St. Pierre's avatar Dr. Matthias St. Pierre
Browse files

DRBG: make locking api truly private 



In PR #5295 it was decided that the locking api should remain private
and used only inside libcrypto. However, the locking functions were added
back to `libcrypto.num` by `mkdef.pl`, because the function prototypes
were still listed in `internal/rand.h`. (This header contains functions
which are internal, but shared between libcrypto and libssl.)

This commit moves the prototypes to `rand_lcl.h` and changes the names
to lowercase, following the convention therein. It also corrects an
outdated documenting comment.

Reviewed-by: default avatarRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5375)
parent 4d921bfb

crypto/err/openssl.txt

+1 −1
Original line number Diff line number Diff line
@@ -890,7 +890,7 @@ RAND_F_DRBG_GET_ENTROPY:105:drbg_get_entropy 
RAND_F_DRBG_SETUP:117:drbg_setup

RAND_F_GET_ENTROPY:106:get_entropy

RAND_F_RAND_BYTES:100:RAND_bytes

RAND_F_RAND_DRBG_ENABLE_LOCKING:119:RAND_DRBG_enable_locking

RAND_F_RAND_DRBG_ENABLE_LOCKING:119:rand_drbg_enable_locking

RAND_F_RAND_DRBG_GENERATE:107:RAND_DRBG_generate

RAND_F_RAND_DRBG_INSTANTIATE:108:RAND_DRBG_instantiate

RAND_F_RAND_DRBG_NEW:109:RAND_DRBG_new

crypto/rand/drbg_lib.c

+21 −21
Original line number Diff line number Diff line
@@ -94,17 +94,17 @@ static RAND_DRBG *drbg_private; 
 * LOCKING

 *

 * The three shared DRBGs are intended to be used concurrently, so they

 * support locking by default. It is the callers responsibility to wrap

 * calls to functions like RAND_DRBG_generate() which modify the DRBGs

 * internal state with calls to RAND_DRBG_lock() and RAND_DRBG_unlock().

 * The functions RAND_bytes() and RAND_priv_bytes() take the locks

 * automatically, so using the RAND api is thread safe as before.

 * support locking. The RAND methods take the locks automatically, so using

 * the RAND api (in particular RAND_bytes() and RAND_priv_bytes()) is

 * thread-safe. Note however that accessing the shared DRBGs directly via

 * the RAND_DRBG interface is *not* thread-safe.

 *

 * All other DRBG instances don't have locking enabled by default, because

 * they are intendended to be used by a single thread. If it is desired,

 * locking can be enabled using RAND_DRBG_enable_locking(). However, instead

 * of accessing a single DRBG instance concurrently from different threads,

 * it is recommended to instantiate a separate DRBG instance per thread.

 * All other DRBG instances don't support locking, because they are

 * intendended to be used by a single thread. Instead of accessing a single

 * DRBG instance concurrently from different threads, it is recommended to

 * instantiate a separate DRBG instance per thread. Using the same shared

 * DRBG (preferrably the public DRBG) as parent of DRBG instances on

 * different threads is safe.

 */
@@ -708,7 +708,7 @@ int RAND_DRBG_set_reseed_time_interval(RAND_DRBG *drbg, time_t interval) 
 *

 * Returns 1 on success, 0 on failure.

 */

int RAND_DRBG_lock(RAND_DRBG *drbg)

int rand_drbg_lock(RAND_DRBG *drbg)

{

    if (drbg->lock != NULL)

        return CRYPTO_THREAD_write_lock(drbg->lock);
@@ -722,7 +722,7 @@ int RAND_DRBG_lock(RAND_DRBG *drbg) 
 *

 * Returns 1 on success, 0 on failure.

 */

int RAND_DRBG_unlock(RAND_DRBG *drbg)

int rand_drbg_unlock(RAND_DRBG *drbg)

{

    if (drbg->lock != NULL)

        return CRYPTO_THREAD_unlock(drbg->lock);
@@ -738,7 +738,7 @@ int RAND_DRBG_unlock(RAND_DRBG *drbg) 
 *

 * Returns 1 on success, 0 on failure.

 */

int RAND_DRBG_enable_locking(RAND_DRBG *drbg)

int rand_drbg_enable_locking(RAND_DRBG *drbg)

{

    if (drbg->state != DRBG_UNINITIALISED) {

        RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING,
@@ -797,7 +797,7 @@ static RAND_DRBG *drbg_setup(RAND_DRBG *parent) 
    if (drbg == NULL)

        return NULL;



    if (RAND_DRBG_enable_locking(drbg) == 0)

    if (rand_drbg_enable_locking(drbg) == 0)

        goto err;



    if (parent == NULL) {
@@ -869,9 +869,9 @@ static int drbg_bytes(unsigned char *out, int count) 
    if (drbg == NULL)

        return 0;



    RAND_DRBG_lock(drbg);

    rand_drbg_lock(drbg);

    ret = RAND_DRBG_bytes(drbg, out, count);

    RAND_DRBG_unlock(drbg);

    rand_drbg_unlock(drbg);



    return ret;

}
@@ -898,11 +898,11 @@ static int drbg_add(const void *buf, int num, double randomness) 
        return 0;

    }



    RAND_DRBG_lock(drbg);

    rand_drbg_lock(drbg);

    ret = rand_drbg_restart(drbg, buf,

                            (size_t)(unsigned int)num,

                            (size_t)(8*randomness));

    RAND_DRBG_unlock(drbg);

    rand_drbg_unlock(drbg);



    return ret;

}
@@ -922,9 +922,9 @@ static int drbg_status(void) 
    if (drbg == NULL)

        return 0;



    RAND_DRBG_lock(drbg);

    rand_drbg_lock(drbg);

    ret = drbg->state == DRBG_READY ? 1 : 0;

    RAND_DRBG_unlock(drbg);

    rand_drbg_unlock(drbg);

    return ret;

}

crypto/rand/rand_err.c

+1 −1
Original line number Diff line number Diff line
@@ -20,7 +20,7 @@ static const ERR_STRING_DATA RAND_str_functs[] = { 
    {ERR_PACK(ERR_LIB_RAND, RAND_F_GET_ENTROPY, 0), "get_entropy"},

    {ERR_PACK(ERR_LIB_RAND, RAND_F_RAND_BYTES, 0), "RAND_bytes"},

    {ERR_PACK(ERR_LIB_RAND, RAND_F_RAND_DRBG_ENABLE_LOCKING, 0),

     "RAND_DRBG_enable_locking"},

     "rand_drbg_enable_locking"},

    {ERR_PACK(ERR_LIB_RAND, RAND_F_RAND_DRBG_GENERATE, 0),

     "RAND_DRBG_generate"},

    {ERR_PACK(ERR_LIB_RAND, RAND_F_RAND_DRBG_INSTANTIATE, 0),

crypto/rand/rand_lcl.h

+6 −0
Original line number Diff line number Diff line
@@ -222,6 +222,12 @@ size_t rand_drbg_get_additional_data(unsigned char **pout, size_t max_len); 
int rand_drbg_restart(RAND_DRBG *drbg,

                      const unsigned char *buffer, size_t len, size_t entropy);



/* locking api */

int rand_drbg_lock(RAND_DRBG *drbg);

int rand_drbg_unlock(RAND_DRBG *drbg);

int rand_drbg_enable_locking(RAND_DRBG *drbg);





/* initializes the AES-CTR DRBG implementation */

int drbg_ctr_init(RAND_DRBG *drbg);

crypto/rand/rand_lib.c

+6 −6
Original line number Diff line number Diff line
@@ -203,13 +203,13 @@ size_t rand_drbg_get_entropy(RAND_DRBG *drbg, 
             * generating bits from it. (Note: taking the lock will be a no-op

             * if locking if drbg->parent->lock == NULL.)

             */

            RAND_DRBG_lock(drbg->parent);

            rand_drbg_lock(drbg->parent);

            if (RAND_DRBG_generate(drbg->parent,

                                   buffer, bytes_needed,

                                   0,

                                   (unsigned char *)drbg, sizeof(*drbg)) != 0)

                bytes = bytes_needed;

            RAND_DRBG_unlock(drbg->parent);

            rand_drbg_unlock(drbg->parent);



            entropy_available = RAND_POOL_add_end(pool, bytes, 8 * bytes);

        }
@@ -405,9 +405,9 @@ int RAND_poll(void) 
        if (drbg == NULL)

            return 0;



        RAND_DRBG_lock(drbg);

        rand_drbg_lock(drbg);

        ret = rand_drbg_restart(drbg, NULL, 0, 0);

        RAND_DRBG_unlock(drbg);

        rand_drbg_unlock(drbg);



        return ret;
@@ -797,9 +797,9 @@ int RAND_priv_bytes(unsigned char *buf, int num) 
        return 0;



    /* We have to lock the DRBG before generating bits from it. */

    RAND_DRBG_lock(drbg);

    rand_drbg_lock(drbg);

    ret = RAND_DRBG_bytes(drbg, buf, num);

    RAND_DRBG_unlock(drbg);

    rand_drbg_unlock(drbg);

    return ret;

}