Make the public and private DRBG thread local
[openssl.git] / crypto / rand / drbg_lib.c
index 360e77565c0e4b0ada4b434e3b0cc99aa7debff1..723f6307fdad5ef400ccf9a883c892a172a79bac 100644 (file)
@@ -14,6 +14,7 @@
 #include "rand_lcl.h"
 #include "internal/thread_once.h"
 #include "internal/rand_int.h"
+#include "internal/cryptlib_int.h"
 
 /*
  * Support framework for NIST SP 800-90A DRBG, AES-CTR mode.
  * sources or by consuming randomnes which was added by RAND_add()
  */
 static RAND_DRBG *drbg_master;
-/*
- * THE PUBLIC DRBG
- *
- * Used by default for generating random bytes using RAND_bytes().
- */
-static RAND_DRBG *drbg_public;
-/*
- * THE PRIVATE DRBG
- *
- * Used by default for generating private keys using RAND_priv_bytes()
- */
-static RAND_DRBG *drbg_private;
 /*+
  * DRBG HIERARCHY
  *
@@ -112,6 +101,8 @@ static RAND_DRBG *drbg_private;
 static const char ossl_pers_string[] = "OpenSSL NIST SP 800-90A DRBG";
 
 static CRYPTO_ONCE rand_drbg_init = CRYPTO_ONCE_STATIC_INIT;
+static CRYPTO_THREAD_LOCAL private_drbg_thread_local_key;
+static CRYPTO_THREAD_LOCAL public_drbg_thread_local_key;
 
 
 
@@ -218,7 +209,7 @@ static RAND_DRBG *rand_drbg_new(int secure,
 
     if (drbg == NULL) {
         RANDerr(RAND_F_RAND_DRBG_NEW, ERR_R_MALLOC_FAILURE);
-        goto err;
+        return NULL;
     }
 
     drbg->secure = secure && CRYPTO_secure_allocated(drbg);
@@ -236,13 +227,18 @@ static RAND_DRBG *rand_drbg_new(int secure,
     if (RAND_DRBG_set(drbg, type, flags) == 0)
         goto err;
 
-    if (parent != NULL && 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
-         */
-        RANDerr(RAND_F_RAND_DRBG_NEW, RAND_R_PARENT_STRENGTH_TOO_WEAK);
-        goto err;
+    if (parent != 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);
     }
 
     if (!RAND_DRBG_set_callbacks(drbg, rand_drbg_get_entropy,
@@ -327,7 +323,8 @@ int RAND_DRBG_instantiate(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, 0);
     if (entropylen < drbg->min_entropylen
         || entropylen > drbg->max_entropylen) {
         RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_RETRIEVING_ENTROPY);
@@ -411,7 +408,8 @@ int RAND_DRBG_uninstantiate(RAND_DRBG *drbg)
  * 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;
@@ -435,7 +433,9 @@ 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);
@@ -551,7 +551,7 @@ int rand_drbg_restart(RAND_DRBG *drbg,
             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);
         }
     }
 
@@ -627,7 +627,7 @@ int RAND_DRBG_generate(RAND_DRBG *drbg, unsigned char *out, size_t outlen,
     }
 
     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;
         }
@@ -896,7 +896,8 @@ static RAND_DRBG *drbg_setup(RAND_DRBG *parent)
     if (drbg == NULL)
         return NULL;
 
-    if (rand_drbg_enable_locking(drbg) == 0)
+    /* Only the master DRBG needs to have a lock */
+    if (parent == NULL && rand_drbg_enable_locking(drbg) == 0)
         goto err;
 
     /* enable seed propagation */
@@ -924,6 +925,8 @@ err:
  */
 DEFINE_RUN_ONCE_STATIC(do_rand_drbg_init)
 {
+    int ret = 1;
+
     /*
      * ensure that libcrypto is initialized, otherwise the
      * DRBG locks are not cleaned up properly
@@ -931,11 +934,14 @@ DEFINE_RUN_ONCE_STATIC(do_rand_drbg_init)
     if (!OPENSSL_init_crypto(0, NULL))
         return 0;
 
+    ossl_init_thread_start(OPENSSL_INIT_THREAD_RAND);
+
     drbg_master = drbg_setup(NULL);
-    drbg_public = drbg_setup(drbg_master);
-    drbg_private = drbg_setup(drbg_master);
 
-    if (drbg_master == NULL || drbg_public == NULL || drbg_private == NULL)
+    ret &= CRYPTO_THREAD_init_local(&private_drbg_thread_local_key, NULL);
+    ret &= CRYPTO_THREAD_init_local(&public_drbg_thread_local_key, NULL);
+
+    if (drbg_master == NULL || ret == 0)
         return 0;
 
     return 1;
@@ -944,11 +950,22 @@ DEFINE_RUN_ONCE_STATIC(do_rand_drbg_init)
 /* Clean up the global DRBGs before exit */
 void rand_drbg_cleanup_int(void)
 {
-    RAND_DRBG_free(drbg_private);
-    RAND_DRBG_free(drbg_public);
     RAND_DRBG_free(drbg_master);
+    drbg_master = NULL;
 
-    drbg_private = drbg_public = drbg_master = NULL;
+    CRYPTO_THREAD_cleanup_local(&private_drbg_thread_local_key);
+    CRYPTO_THREAD_cleanup_local(&public_drbg_thread_local_key);
+}
+
+void drbg_delete_thread_state()
+{
+    RAND_DRBG *drbg;
+
+    drbg = CRYPTO_THREAD_get_local(&public_drbg_thread_local_key);
+    RAND_DRBG_free(drbg);
+
+    drbg = CRYPTO_THREAD_get_local(&private_drbg_thread_local_key);
+    RAND_DRBG_free(drbg);
 }
 
 /* Implements the default OpenSSL RAND_bytes() method */
@@ -960,9 +977,7 @@ static int drbg_bytes(unsigned char *out, int count)
     if (drbg == NULL)
         return 0;
 
-    rand_drbg_lock(drbg);
     ret = RAND_DRBG_bytes(drbg, out, count);
-    rand_drbg_unlock(drbg);
 
     return ret;
 }
@@ -1038,10 +1053,18 @@ RAND_DRBG *RAND_DRBG_get0_master(void)
  */
 RAND_DRBG *RAND_DRBG_get0_public(void)
 {
+    RAND_DRBG *drbg;
+
     if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
         return NULL;
 
-    return drbg_public;
+    drbg = CRYPTO_THREAD_get_local(&public_drbg_thread_local_key);
+    if (drbg == NULL) {
+        ossl_init_thread_start(OPENSSL_INIT_THREAD_RAND);
+        drbg = drbg_setup(drbg_master);
+        CRYPTO_THREAD_set_local(&public_drbg_thread_local_key, drbg);
+    }
+    return drbg;
 }
 
 /*
@@ -1050,10 +1073,18 @@ RAND_DRBG *RAND_DRBG_get0_public(void)
  */
 RAND_DRBG *RAND_DRBG_get0_private(void)
 {
+    RAND_DRBG *drbg;
+
     if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
         return NULL;
 
-    return drbg_private;
+    drbg = CRYPTO_THREAD_get_local(&private_drbg_thread_local_key);
+    if (drbg == NULL) {
+        ossl_init_thread_start(OPENSSL_INIT_THREAD_RAND);
+        drbg = drbg_setup(drbg_master);
+        CRYPTO_THREAD_set_local(&private_drbg_thread_local_key, drbg);
+    }
+    return drbg;
 }
 
 RAND_METHOD rand_meth = {