Make rand_pool buffers more dynamic in their sizing.

[openssl.git] / crypto / rand / rand_lib.c

diff --git a/crypto/rand/rand_lib.c b/crypto/rand/rand_lib.c
index d2f5be1a65d656ffe3db73ef07bea3c323b9cb03..8b44b5502d2fce9e55e574b37fe982a5747259da 100644 (file)
--- a/crypto/rand/rand_lib.c
+++ b/crypto/rand/rand_lib.c
@@ -1,7 +1,7 @@
 /*
  * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
  *
 /*
  * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
  *

- * Licensed under the OpenSSL license (the "License").  You may not use
+ * Licensed under the Apache License 2.0 (the "License").  You may not use

  * this file except in compliance with the License.  You can obtain a copy
  * in the file LICENSE in the source distribution or at
  * https://www.openssl.org/source/license.html
  * this file except in compliance with the License.  You can obtain a copy
  * in the file LICENSE in the source distribution or at
  * https://www.openssl.org/source/license.html


@@ -17,21 +17,20 @@
 #include "rand_lcl.h"
 #include "e_os.h"
 
 #include "rand_lcl.h"
 #include "e_os.h"
 

-#ifndef OPENSSL_NO_ENGINE
+#ifndef FIPS_MODE
+# ifndef OPENSSL_NO_ENGINE

 /* non-NULL if default_RAND_meth is ENGINE-provided */
 static ENGINE *funct_ref;
 static CRYPTO_RWLOCK *rand_engine_lock;
 /* non-NULL if default_RAND_meth is ENGINE-provided */
 static ENGINE *funct_ref;
 static CRYPTO_RWLOCK *rand_engine_lock;

-#endif
+# endif

 static CRYPTO_RWLOCK *rand_meth_lock;
 static const RAND_METHOD *default_RAND_meth;
 static CRYPTO_ONCE rand_init = CRYPTO_ONCE_STATIC_INIT;
 
 static CRYPTO_RWLOCK *rand_meth_lock;
 static const RAND_METHOD *default_RAND_meth;
 static CRYPTO_ONCE rand_init = CRYPTO_ONCE_STATIC_INIT;
 

-int rand_fork_count;
-
-static CRYPTO_RWLOCK *rand_nonce_lock;
-static int rand_nonce_count;
-

 static int rand_inited = 0;
 static int rand_inited = 0;

+#endif /* FIPS_MODE */
+
+int rand_fork_count;

 
 #ifdef OPENSSL_RAND_SEED_RDTSC
 /*
 
 #ifdef OPENSSL_RAND_SEED_RDTSC
 /*


@@ -137,7 +136,7 @@ size_t rand_drbg_get_entropy(RAND_DRBG *drbg,
     size_t entropy_available = 0;
     RAND_POOL *pool;
 
     size_t entropy_available = 0;
     RAND_POOL *pool;
 

-    if (drbg->parent && drbg->strength > drbg->parent->strength) {
+    if (drbg->parent != NULL && drbg->strength > drbg->parent->strength) {

         /*
          * We currently don't support the algorithm from NIST SP 800-90C
          * 10.1.2 to use a weaker DRBG as source
         /*
          * We currently don't support the algorithm from NIST SP 800-90C
          * 10.1.2 to use a weaker DRBG as source


@@ -150,12 +149,12 @@ size_t rand_drbg_get_entropy(RAND_DRBG *drbg,
         pool = drbg->seed_pool;
         pool->entropy_requested = entropy;
     } else {
         pool = drbg->seed_pool;
         pool->entropy_requested = entropy;
     } else {

-        pool = rand_pool_new(entropy, min_len, max_len);
+        pool = rand_pool_new(entropy, drbg->secure, min_len, max_len);

         if (pool == NULL)
             return 0;
     }
 
         if (pool == NULL)
             return 0;
     }
 

-    if (drbg->parent) {
+    if (drbg->parent != NULL) {

         size_t bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/);
         unsigned char *buffer = rand_pool_add_begin(pool, bytes_needed);
 
         size_t bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/);
         unsigned char *buffer = rand_pool_add_begin(pool, bytes_needed);
 


@@ -183,17 +182,6 @@ size_t rand_drbg_get_entropy(RAND_DRBG *drbg,
         }
 
     } else {
         }
 
     } else {

-        if (prediction_resistance) {
-            /*
-             * We don't have any entropy sources that comply with the NIST
-             * standard to provide prediction resistance (see NIST SP 800-90C,
-             * Section 5.4).
-             */
-            RANDerr(RAND_F_RAND_DRBG_GET_ENTROPY,
-                    RAND_R_PREDICTION_RESISTANCE_NOT_SUPPORTED);
-            goto err;
-        }
-

         /* Get entropy by polling system entropy sources. */
         entropy_available = rand_pool_acquire_entropy(pool);
     }
         /* Get entropy by polling system entropy sources. */
         entropy_available = rand_pool_acquire_entropy(pool);
     }


@@ -203,7 +191,6 @@ size_t rand_drbg_get_entropy(RAND_DRBG *drbg,
         *pout = rand_pool_detach(pool);
     }
 
         *pout = rand_pool_detach(pool);
     }
 

- err:

     if (drbg->seed_pool == NULL)
         rand_pool_free(pool);
     return ret;
     if (drbg->seed_pool == NULL)
         rand_pool_free(pool);
     return ret;


@@ -216,57 +203,12 @@ size_t rand_drbg_get_entropy(RAND_DRBG *drbg,
 void rand_drbg_cleanup_entropy(RAND_DRBG *drbg,
                                unsigned char *out, size_t outlen)
 {
 void rand_drbg_cleanup_entropy(RAND_DRBG *drbg,
                                unsigned char *out, size_t outlen)
 {

-    if (drbg->seed_pool == NULL)
-        OPENSSL_secure_clear_free(out, outlen);
-}
-
-
-/*
- * Implements the get_nonce() callback (see RAND_DRBG_set_callbacks())
- *
- */
-size_t rand_drbg_get_nonce(RAND_DRBG *drbg,
-                           unsigned char **pout,
-                           int entropy, size_t min_len, size_t max_len)
-{
-    size_t ret = 0;
-    RAND_POOL *pool;
-
-    struct {
-        void * instance;
-        int count;
-    } data = { 0 };
-
-    pool = rand_pool_new(0, min_len, max_len);
-    if (pool == NULL)
-        return 0;
-
-    if (rand_pool_add_nonce_data(pool) == 0)
-        goto err;
-
-    data.instance = drbg;
-    CRYPTO_atomic_add(&rand_nonce_count, 1, &data.count, rand_nonce_lock);
-
-    if (rand_pool_add(pool, (unsigned char *)&data, sizeof(data), 0) == 0)
-        goto err;
-
-    ret   = rand_pool_length(pool);
-    *pout = rand_pool_detach(pool);
-
- err:
-    rand_pool_free(pool);
-
-    return ret;
-}
-
-/*
- * Implements the cleanup_nonce() callback (see RAND_DRBG_set_callbacks())
- *
- */
-void rand_drbg_cleanup_nonce(RAND_DRBG *drbg,
-                             unsigned char *out, size_t outlen)
-{
-    OPENSSL_secure_clear_free(out, outlen);
+    if (drbg->seed_pool == NULL) {
+        if (drbg->secure)
+            OPENSSL_secure_clear_free(out, outlen);
+        else
+            OPENSSL_clear_free(out, outlen);
+    }

 }
 
 /*
 }
 
 /*


@@ -303,39 +245,32 @@ void rand_fork(void)
     rand_fork_count++;
 }
 
     rand_fork_count++;
 }
 

+#ifndef FIPS_MODE

 DEFINE_RUN_ONCE_STATIC(do_rand_init)
 {
 DEFINE_RUN_ONCE_STATIC(do_rand_init)
 {

-#ifndef OPENSSL_NO_ENGINE
+# ifndef OPENSSL_NO_ENGINE

     rand_engine_lock = CRYPTO_THREAD_lock_new();
     if (rand_engine_lock == NULL)
         return 0;
     rand_engine_lock = CRYPTO_THREAD_lock_new();
     if (rand_engine_lock == NULL)
         return 0;

-#endif
+# endif

 
     rand_meth_lock = CRYPTO_THREAD_lock_new();
     if (rand_meth_lock == NULL)
 
     rand_meth_lock = CRYPTO_THREAD_lock_new();
     if (rand_meth_lock == NULL)

-        goto err1;
-
-    rand_nonce_lock = CRYPTO_THREAD_lock_new();
-    if (rand_nonce_lock == NULL)
-        goto err2;
+        goto err;

 
     if (!rand_pool_init())
 
     if (!rand_pool_init())

-        goto err3;
+        goto err;

 
     rand_inited = 1;
     return 1;
 
 
     rand_inited = 1;
     return 1;
 

-err3:
-    CRYPTO_THREAD_lock_free(rand_nonce_lock);
-    rand_nonce_lock = NULL;
-err2:
+ err:

     CRYPTO_THREAD_lock_free(rand_meth_lock);
     rand_meth_lock = NULL;
     CRYPTO_THREAD_lock_free(rand_meth_lock);
     rand_meth_lock = NULL;

-err1:
-#ifndef OPENSSL_NO_ENGINE
+# ifndef OPENSSL_NO_ENGINE

     CRYPTO_THREAD_lock_free(rand_engine_lock);
     rand_engine_lock = NULL;
     CRYPTO_THREAD_lock_free(rand_engine_lock);
     rand_engine_lock = NULL;

-#endif
+# endif

     return 0;
 }
 
     return 0;
 }
 


@@ -350,19 +285,18 @@ void rand_cleanup_int(void)
         meth->cleanup();
     RAND_set_rand_method(NULL);
     rand_pool_cleanup();
         meth->cleanup();
     RAND_set_rand_method(NULL);
     rand_pool_cleanup();

-#ifndef OPENSSL_NO_ENGINE
+# ifndef OPENSSL_NO_ENGINE

     CRYPTO_THREAD_lock_free(rand_engine_lock);
     rand_engine_lock = NULL;
     CRYPTO_THREAD_lock_free(rand_engine_lock);
     rand_engine_lock = NULL;

-#endif
+# endif

     CRYPTO_THREAD_lock_free(rand_meth_lock);
     rand_meth_lock = NULL;
     CRYPTO_THREAD_lock_free(rand_meth_lock);
     rand_meth_lock = NULL;

-    CRYPTO_THREAD_lock_free(rand_nonce_lock);
-    rand_nonce_lock = NULL;

     rand_inited = 0;
 }
 
     rand_inited = 0;
 }
 

+/* TODO(3.0): Do we need to handle this somehow in the FIPS module? */

 /*
 /*

- * RAND_close_seed_files() ensures that any seed file decriptors are
+ * RAND_close_seed_files() ensures that any seed file descriptors are

  * closed after use.
  */
 void RAND_keep_random_devices_open(int keep)
  * closed after use.
  */
 void RAND_keep_random_devices_open(int keep)


@@ -382,8 +316,6 @@ int RAND_poll(void)
 {
     int ret = 0;
 
 {
     int ret = 0;
 

-    RAND_POOL *pool = NULL;
-

     const RAND_METHOD *meth = RAND_get_rand_method();
 
     if (meth == RAND_OpenSSL()) {
     const RAND_METHOD *meth = RAND_get_rand_method();
 
     if (meth == RAND_OpenSSL()) {


@@ -400,9 +332,11 @@ int RAND_poll(void)
         return ret;
 
     } else {
         return ret;
 
     } else {

+        RAND_POOL *pool = NULL;
+

         /* fill random pool and seed the current legacy RNG */
         /* fill random pool and seed the current legacy RNG */

-        pool = rand_pool_new(RAND_DRBG_STRENGTH,
-                             RAND_DRBG_STRENGTH / 8,
+        pool = rand_pool_new(RAND_DRBG_STRENGTH, 1,
+                             (RAND_DRBG_STRENGTH + 7) / 8,

                              RAND_POOL_MAX_LENGTH);
         if (pool == NULL)
             return 0;
                              RAND_POOL_MAX_LENGTH);
         if (pool == NULL)
             return 0;


@@ -417,20 +351,24 @@ int RAND_poll(void)
             goto err;
 
         ret = 1;
             goto err;
 
         ret = 1;

+
+     err:
+        rand_pool_free(pool);

     }
 
     }
 

-err:
-    rand_pool_free(pool);

     return ret;
 }
     return ret;
 }

+#endif /* FIPS_MODE */

 
 /*
  * Allocate memory and initialize a new random pool
  */
 
 
 /*
  * Allocate memory and initialize a new random pool
  */
 

-RAND_POOL *rand_pool_new(int entropy_requested, size_t min_len, size_t max_len)
+RAND_POOL *rand_pool_new(int entropy_requested, int secure,
+                         size_t min_len, size_t max_len)

 {
     RAND_POOL *pool = OPENSSL_zalloc(sizeof(*pool));
 {
     RAND_POOL *pool = OPENSSL_zalloc(sizeof(*pool));

+    size_t min_alloc_size = RAND_POOL_MIN_ALLOCATION(secure);

 
     if (pool == NULL) {
         RANDerr(RAND_F_RAND_POOL_NEW, ERR_R_MALLOC_FAILURE);
 
     if (pool == NULL) {
         RANDerr(RAND_F_RAND_POOL_NEW, ERR_R_MALLOC_FAILURE);


@@ -440,14 +378,22 @@ RAND_POOL *rand_pool_new(int entropy_requested, size_t min_len, size_t max_len)
     pool->min_len = min_len;
     pool->max_len = (max_len > RAND_POOL_MAX_LENGTH) ?
         RAND_POOL_MAX_LENGTH : max_len;
     pool->min_len = min_len;
     pool->max_len = (max_len > RAND_POOL_MAX_LENGTH) ?
         RAND_POOL_MAX_LENGTH : max_len;

+    pool->alloc_len = min_len < min_alloc_size ? min_alloc_size : min_len;
+    if (pool->alloc_len > pool->max_len)
+        pool->alloc_len = pool->max_len;
+
+    if (secure)
+        pool->buffer = OPENSSL_secure_zalloc(pool->alloc_len);
+    else
+        pool->buffer = OPENSSL_zalloc(pool->alloc_len);

 
 

-    pool->buffer = OPENSSL_secure_zalloc(pool->max_len);

     if (pool->buffer == NULL) {
         RANDerr(RAND_F_RAND_POOL_NEW, ERR_R_MALLOC_FAILURE);
         goto err;
     }
 
     pool->entropy_requested = entropy_requested;
     if (pool->buffer == NULL) {
         RANDerr(RAND_F_RAND_POOL_NEW, ERR_R_MALLOC_FAILURE);
         goto err;
     }
 
     pool->entropy_requested = entropy_requested;

+    pool->secure = secure;

 
     return pool;
 
 
     return pool;
 


@@ -482,7 +428,7 @@ RAND_POOL *rand_pool_attach(const unsigned char *buffer, size_t len,
 
     pool->attached = 1;
 
 
     pool->attached = 1;
 

-    pool->min_len = pool->max_len = pool->len;
+    pool->min_len = pool->max_len = pool->alloc_len = pool->len;

     pool->entropy = entropy;
 
     return pool;
     pool->entropy = entropy;
 
     return pool;


@@ -502,8 +448,13 @@ void rand_pool_free(RAND_POOL *pool)
      * to rand_pool_attach() as `const unsigned char*`.
      * (see corresponding comment in rand_pool_attach()).
      */
      * to rand_pool_attach() as `const unsigned char*`.
      * (see corresponding comment in rand_pool_attach()).
      */

-    if (!pool->attached)
-        OPENSSL_secure_clear_free(pool->buffer, pool->max_len);
+    if (!pool->attached) {
+        if (pool->secure)
+            OPENSSL_secure_clear_free(pool->buffer, pool->alloc_len);
+        else
+            OPENSSL_clear_free(pool->buffer, pool->alloc_len);
+    }
+

     OPENSSL_free(pool);
 }
 
     OPENSSL_free(pool);
 }
 


@@ -634,6 +585,36 @@ size_t rand_pool_bytes_remaining(RAND_POOL *pool)
     return pool->max_len - pool->len;
 }
 
     return pool->max_len - pool->len;
 }
 

+static int rand_pool_grow(RAND_POOL *pool, size_t len)
+{
+    if (len > pool->alloc_len - pool->len) {
+        unsigned char *p;
+        const size_t limit = pool->max_len / 2;
+        size_t newlen = pool->alloc_len;
+
+        do
+            newlen = newlen < limit ? newlen * 2 : pool->max_len;
+        while (len > newlen - pool->len);
+
+        if (pool->secure)
+            p = OPENSSL_secure_zalloc(newlen);
+        else
+            p = OPENSSL_zalloc(newlen);
+        if (p == NULL) {
+            RANDerr(RAND_F_RAND_POOL_GROW, ERR_R_MALLOC_FAILURE);
+            return 0;
+        }
+        memcpy(p, pool->buffer, pool->len);
+        if (pool->secure)
+            OPENSSL_secure_clear_free(pool->buffer, pool->alloc_len);
+        else
+            OPENSSL_clear_free(pool->buffer, pool->alloc_len);
+        pool->buffer = p;
+        pool->alloc_len = newlen;
+    }
+    return 1;
+}
+

 /*
  * Add random bytes to the random pool.
  *
 /*
  * Add random bytes to the random pool.
  *


@@ -657,6 +638,8 @@ int rand_pool_add(RAND_POOL *pool,
     }
 
     if (len > 0) {
     }
 
     if (len > 0) {

+        if (!rand_pool_grow(pool, len))
+            return 0;

         memcpy(pool->buffer + pool->len, buffer, len);
         pool->len += len;
         pool->entropy += entropy;
         memcpy(pool->buffer + pool->len, buffer, len);
         pool->len += len;
         pool->entropy += entropy;


@@ -689,9 +672,11 @@ unsigned char *rand_pool_add_begin(RAND_POOL *pool, size_t len)
 
     if (pool->buffer == NULL) {
         RANDerr(RAND_F_RAND_POOL_ADD_BEGIN, ERR_R_INTERNAL_ERROR);
 
     if (pool->buffer == NULL) {
         RANDerr(RAND_F_RAND_POOL_ADD_BEGIN, ERR_R_INTERNAL_ERROR);

-        return 0;
+        return NULL;

     }
 
     }
 

+    if (!rand_pool_grow(pool, len))
+        return NULL;

     return pool->buffer + pool->len;
 }
 
     return pool->buffer + pool->len;
 }
 


@@ -719,23 +704,28 @@ int rand_pool_add_end(RAND_POOL *pool, size_t len, size_t entropy)
     return 1;
 }
 
     return 1;
 }
 

+#ifndef FIPS_MODE

 int RAND_set_rand_method(const RAND_METHOD *meth)
 {
     if (!RUN_ONCE(&rand_init, do_rand_init))
         return 0;
 
     CRYPTO_THREAD_write_lock(rand_meth_lock);
 int RAND_set_rand_method(const RAND_METHOD *meth)
 {
     if (!RUN_ONCE(&rand_init, do_rand_init))
         return 0;
 
     CRYPTO_THREAD_write_lock(rand_meth_lock);

-#ifndef OPENSSL_NO_ENGINE
+# ifndef OPENSSL_NO_ENGINE

     ENGINE_finish(funct_ref);
     funct_ref = NULL;
     ENGINE_finish(funct_ref);
     funct_ref = NULL;

-#endif
+# endif

     default_RAND_meth = meth;
     CRYPTO_THREAD_unlock(rand_meth_lock);
     return 1;
 }
     default_RAND_meth = meth;
     CRYPTO_THREAD_unlock(rand_meth_lock);
     return 1;
 }

+#endif

 
 const RAND_METHOD *RAND_get_rand_method(void)
 {
 
 const RAND_METHOD *RAND_get_rand_method(void)
 {

+#ifdef FIPS_MODE
+    return NULL;
+#else

     const RAND_METHOD *tmp_meth = NULL;
 
     if (!RUN_ONCE(&rand_init, do_rand_init))
     const RAND_METHOD *tmp_meth = NULL;
 
     if (!RUN_ONCE(&rand_init, do_rand_init))


@@ -743,7 +733,7 @@ const RAND_METHOD *RAND_get_rand_method(void)
 
     CRYPTO_THREAD_write_lock(rand_meth_lock);
     if (default_RAND_meth == NULL) {
 
     CRYPTO_THREAD_write_lock(rand_meth_lock);
     if (default_RAND_meth == NULL) {

-#ifndef OPENSSL_NO_ENGINE
+# ifndef OPENSSL_NO_ENGINE

         ENGINE *e;
 
         /* If we have an engine that can do RAND, use it. */
         ENGINE *e;
 
         /* If we have an engine that can do RAND, use it. */


@@ -755,16 +745,17 @@ const RAND_METHOD *RAND_get_rand_method(void)
             ENGINE_finish(e);
             default_RAND_meth = &rand_meth;
         }
             ENGINE_finish(e);
             default_RAND_meth = &rand_meth;
         }

-#else
+# else

         default_RAND_meth = &rand_meth;
         default_RAND_meth = &rand_meth;

-#endif
+# endif

     }
     tmp_meth = default_RAND_meth;
     CRYPTO_THREAD_unlock(rand_meth_lock);
     return tmp_meth;
     }
     tmp_meth = default_RAND_meth;
     CRYPTO_THREAD_unlock(rand_meth_lock);
     return tmp_meth;

+#endif

 }
 
 }
 

-#ifndef OPENSSL_NO_ENGINE
+#if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODE)

 int RAND_set_rand_engine(ENGINE *engine)
 {
     const RAND_METHOD *tmp_meth = NULL;
 int RAND_set_rand_engine(ENGINE *engine)
 {
     const RAND_METHOD *tmp_meth = NULL;


@@ -811,16 +802,16 @@ void RAND_add(const void *buf, int num, double randomness)
  * the default method, then just call RAND_bytes().  Otherwise make
  * sure we're instantiated and use the private DRBG.
  */
  * the default method, then just call RAND_bytes().  Otherwise make
  * sure we're instantiated and use the private DRBG.
  */

-int RAND_priv_bytes(unsigned char *buf, int num)
+int rand_priv_bytes_ex(OPENSSL_CTX *ctx, unsigned char *buf, int num)

 {
 {

-    const RAND_METHOD *meth = RAND_get_rand_method();

     RAND_DRBG *drbg;
     int ret;
     RAND_DRBG *drbg;
     int ret;

+    const RAND_METHOD *meth = RAND_get_rand_method();

 
     if (meth != RAND_OpenSSL())
 
     if (meth != RAND_OpenSSL())

-        return RAND_bytes(buf, num);
+        return meth->bytes(buf, num);

 
 

-    drbg = RAND_DRBG_get0_private();
+    drbg = OPENSSL_CTX_get0_private_drbg(ctx);

     if (drbg == NULL)
         return 0;
 
     if (drbg == NULL)
         return 0;
 


@@ -828,17 +819,38 @@ int RAND_priv_bytes(unsigned char *buf, int num)
     return ret;
 }
 
     return ret;
 }
 

-int RAND_bytes(unsigned char *buf, int num)
+int RAND_priv_bytes(unsigned char *buf, int num)

 {
 {

+    return rand_priv_bytes_ex(NULL, buf, num);
+}
+
+int rand_bytes_ex(OPENSSL_CTX *ctx, unsigned char *buf, int num)
+{
+    RAND_DRBG *drbg;
+    int ret;

     const RAND_METHOD *meth = RAND_get_rand_method();
 
     const RAND_METHOD *meth = RAND_get_rand_method();
 

-    if (meth->bytes != NULL)
-        return meth->bytes(buf, num);
-    RANDerr(RAND_F_RAND_BYTES, RAND_R_FUNC_NOT_IMPLEMENTED);
-    return -1;
+    if (meth != RAND_OpenSSL()) {
+        if (meth->bytes != NULL)
+            return meth->bytes(buf, num);
+        RANDerr(RAND_F_RAND_BYTES_EX, RAND_R_FUNC_NOT_IMPLEMENTED);
+        return -1;
+    }
+
+    drbg = OPENSSL_CTX_get0_public_drbg(ctx);
+    if (drbg == NULL)
+        return 0;
+
+    ret = RAND_DRBG_bytes(drbg, buf, num);
+    return ret;
+}
+
+int RAND_bytes(unsigned char *buf, int num)
+{
+    return rand_bytes_ex(NULL, buf, num);

 }
 
 }
 

-#if !OPENSSL_API_1_1_0
+#if !OPENSSL_API_1_1_0 && !defined(FIPS_MODE)

 int RAND_pseudo_bytes(unsigned char *buf, int num)
 {
     const RAND_METHOD *meth = RAND_get_rand_method();
 int RAND_pseudo_bytes(unsigned char *buf, int num)
 {
     const RAND_METHOD *meth = RAND_get_rand_method();