Tree DRBG with Jitter Entropy root

CMakeLists.txt

@@ -41,9 +41,9 @@ enable_language(C)
 if(FIPS)
   message(STATUS "FIPS build mode configured")
 
+  # Keep below to allow existing rand.c implementation and testing to function.
   if(ENABLE_FIPS_ENTROPY_CPU_JITTER)
     add_definitions(-DFIPS_ENTROPY_SOURCE_JITTER_CPU)
-    add_subdirectory(third_party/jitterentropy)
     message(STATUS "FIPS entropy source method configured: CPU Jitter")
   else()
     add_definitions(-DFIPS_ENTROPY_SOURCE_PASSIVE)
@@ -1020,6 +1020,7 @@ if(BUILD_TESTING)
   endmacro()
 endif()
 
+add_subdirectory(third_party/jitterentropy)
 add_subdirectory(crypto)
 if(BUILD_LIBSSL)
   add_subdirectory(ssl)

crypto/CMakeLists.txt

@@ -592,13 +592,7 @@ target_include_directories(crypto_objects BEFORE PRIVATE ${PROJECT_BINARY_DIR}/s
 target_include_directories(crypto_objects PRIVATE ${PROJECT_SOURCE_DIR}/include)
 
 function(build_libcrypto name module_source)
-  if(FIPS AND ENABLE_FIPS_ENTROPY_CPU_JITTER)
-    # If the jitter cpu entropy source is enabled add an object dependency to
-    # the libcrypto target.
-    add_library(${name} $<TARGET_OBJECTS:crypto_objects> ${CRYPTO_FIPS_OBJECTS} ${module_source} $<TARGET_OBJECTS:jitterentropy>)
-  else()
-    add_library(${name} $<TARGET_OBJECTS:crypto_objects> ${CRYPTO_FIPS_OBJECTS} ${module_source})
-  endif()
+  add_library(${name} $<TARGET_OBJECTS:crypto_objects> ${CRYPTO_FIPS_OBJECTS} ${module_source} $<TARGET_OBJECTS:jitterentropy>)
 
   if(FIPS_DELOCATE OR FIPS_SHARED)
     add_dependencies(${name} bcm_o_target)

crypto/fipsmodule/bcm.c

@@ -36,6 +36,7 @@
 
 #include "rand/new_rand.c"
 #include "rand/entropy/entropy_sources.c"
+#include "rand/entropy/tree_drbg_jitter_entropy.c"
 
 #include <openssl/digest.h>
 #include <openssl/hmac.h>
@@ -263,12 +264,10 @@ static void BORINGSSL_bcm_power_on_self_test(void) {
   OPENSSL_cpuid_setup();
 #endif
 
-#if defined(FIPS_ENTROPY_SOURCE_JITTER_CPU)
   if (jent_entropy_init()) {
     fprintf(stderr, "CPU Jitter entropy RNG initialization failed.\n");
     goto err;
   }
-#endif
 
 #if !defined(OPENSSL_ASAN)
   // Integrity tests cannot run under ASAN because it involves reading the full

crypto/fipsmodule/rand/cpu_jitter_test.cc

@@ -1,8 +1,6 @@
 // Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 // SPDX-License-Identifier: Apache-2.0 OR ISC
 
-#if defined(BORINGSSL_FIPS) && defined(FIPS_ENTROPY_SOURCE_JITTER_CPU)
-
 #include <gtest/gtest.h>
 
 #include "../../test/test_util.h"
@@ -67,5 +65,3 @@ TEST(CPUJitterEntropyTest, Basic) {
   unsigned int jitter_version = 3040000;
   EXPECT_EQ(jitter_version, jent_version());
 }
-
-#endif

crypto/fipsmodule/rand/entropy/entropy_sources.c

@@ -10,19 +10,8 @@
 #include "../internal.h"
 #include "../../delocate.h"
 
-static int entropy_default_initialize(void) {
-  return 1;
-}
-
-static void entropy_default_cleanup(void) {
-}
-
-static int entropy_default_get_seed(uint8_t seed[CTR_DRBG_ENTROPY_LEN]) {
-  CRYPTO_sysrand_for_seed(seed, CTR_DRBG_ENTROPY_LEN);
-  return 1;
-}
-
-static int entropy_default_get_prediction_resistance(
+static int entropy_get_prediction_resistance(
+  const struct entropy_source_t *entropy_source,
   uint8_t pred_resistance[RAND_PRED_RESISTANCE_LEN]) {
   if (have_fast_rdrand() == 1 &&
       rdrand(pred_resistance, RAND_PRED_RESISTANCE_LEN) != 1) {
@@ -31,41 +20,51 @@ static int entropy_default_get_prediction_resistance(
   return 1;
 }
 
-static int entropy_default_randomize(void) {
+static int entropy_get_personalization_string(
+  const struct entropy_source_t *entropy_source,
+  uint8_t personalization_string[CTR_DRBG_ENTROPY_LEN]) {
+  CRYPTO_sysrand(personalization_string, CTR_DRBG_ENTROPY_LEN);
   return 1;
 }
 
-// The default entropy source configuration using
-// - OS randomness source for seeding.
-// - Doesn't have a extra entropy source.
+// - Tree DRBG with Jitter Entropy as root for seeding.
+// - OS as personalization string source.
 // - If run-time is on an Intel CPU and it supports rdrand, use it as a source
 //   for prediction resistance. Otherwise, no source.
-DEFINE_LOCAL_DATA(struct entropy_source, default_entropy_source) {
-  out->initialize = entropy_default_initialize;
-  out->cleanup = entropy_default_cleanup;
-  out->get_seed = entropy_default_get_seed;
-  out->get_extra_entropy = NULL;
+DEFINE_LOCAL_DATA(struct entropy_source_methods, tree_jitter_entropy_source_methods) {
+  out->initialize = tree_jitter_initialize;
+  out->zeroize_thread = tree_jitter_zeroize_thread_drbg;
+  out->free_thread = tree_jitter_free_thread_drbg;
+  out->get_seed = tree_jitter_get_seed;
+  out->get_personalization_string = entropy_get_personalization_string;
   if (have_fast_rdrand() == 1) {
-    out->get_prediction_resistance = entropy_default_get_prediction_resistance;
+    out->get_prediction_resistance = entropy_get_prediction_resistance;
   } else {
     out->get_prediction_resistance = NULL;
   }
-  out->randomize = entropy_default_randomize;
 }
 
-const struct entropy_source * get_entropy_source(void) {
-  const struct entropy_source *ent_source = default_entropy_source();
+struct entropy_source_t * get_entropy_source(void) {
+
+  struct entropy_source_t *entropy_source = OPENSSL_zalloc(sizeof(struct entropy_source_t));
+  if (entropy_source == NULL) {
+    return NULL;
+  }
+
+  entropy_source->methods = tree_jitter_entropy_source_methods();
 
   // Make sure that the function table contains the minimal number of callbacks
   // that we expect. Also make sure that the entropy source is initialized such
   // that calling code can assume that.
-  if (ent_source->cleanup == NULL ||
-      ent_source->get_seed == NULL ||
-      ent_source->randomize == NULL ||
-      ent_source->initialize == NULL ||
-      ent_source->initialize() != 1) {
+  if (entropy_source->methods == NULL ||
+      entropy_source->methods->zeroize_thread == NULL ||
+      entropy_source->methods->free_thread == NULL ||
+      entropy_source->methods->get_seed == NULL ||
+      entropy_source->methods->initialize == NULL ||
+      entropy_source->methods->initialize(entropy_source) != 1) {
+    OPENSSL_free(entropy_source);
     return NULL;
   }
 
-  return ent_source;
+  return entropy_source;
 }

crypto/fipsmodule/rand/entropy/internal.h

@@ -12,18 +12,33 @@
 extern "C" {
 #endif
 
-// I could make these array types!
-struct entropy_source {
-  int (*initialize)(void);
-  void (*cleanup)(void);
-  int (*get_seed)(uint8_t seed[CTR_DRBG_ENTROPY_LEN]);
-  int (*get_extra_entropy)(uint8_t extra_entropy[CTR_DRBG_ENTROPY_LEN]);
-  int (*get_prediction_resistance)(uint8_t pred_resistance[RAND_PRED_RESISTANCE_LEN]);
-  int (*randomize)(void);
+#define ENTROPY_JITTER_MAX_NUM_TRIES (3)
+
+struct entropy_source_t {
+  void *state;
+  const struct entropy_source_methods *methods;
+};
+
+struct entropy_source_methods {
+  int (*initialize)(struct entropy_source_t *entropy_source);
+  void (*zeroize_thread)(struct entropy_source_t *entropy_source);
+  void (*free_thread)(struct entropy_source_t *entropy_source);
+  int (*get_seed)(const struct entropy_source_t *entropy_source,
+    uint8_t seed[CTR_DRBG_ENTROPY_LEN]);
+  int (*get_personalization_string)(const struct entropy_source_t *entropy_source,
+    uint8_t personalization_string[CTR_DRBG_ENTROPY_LEN]);
+  int (*get_prediction_resistance)(const struct entropy_source_t *entropy_source,
+    uint8_t pred_resistance[RAND_PRED_RESISTANCE_LEN]);
 };
 
 // get_entropy_source will return an entropy source configured for the platform.
-const struct entropy_source * get_entropy_source(void);
+struct entropy_source_t * get_entropy_source(void);
+
+OPENSSL_EXPORT int tree_jitter_initialize(struct entropy_source_t *entropy_source);
+OPENSSL_EXPORT void tree_jitter_zeroize_thread_drbg(struct entropy_source_t *entropy_source);
+OPENSSL_EXPORT void tree_jitter_free_thread_drbg(struct entropy_source_t *entropy_source);
+OPENSSL_EXPORT int tree_jitter_get_seed(
+  const struct entropy_source_t *entropy_source, uint8_t seed[CTR_DRBG_ENTROPY_LEN]);
 
 #if defined(__cplusplus)
 }  // extern C