Move CRNG test to providers

Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/11682)

1 files changed, 139 insertions, 0 deletions

diff --git a/providers/implementations/rands/rand_crng_test.c b/providers/implementations/rands/rand_crng_test.c
new file mode 100644
index 0000000000..950cc629d7
--- /dev/null
+++ b/providers/implementations/rands/rand_crng_test.c
@@ -0,0 +1,139 @@
+/*
+ * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright (c) 2019, Oracle and/or its affiliates.  All rights reserved.
+ *
+ * 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
+ */
+
+/*
+ * Implementation of the FIPS 140-2 section 4.9.2 Conditional Tests.
+ */
+
+#include <string.h>
+#include <openssl/evp.h>
+#include "crypto/rand.h"
+#include "internal/thread_once.h"
+#include "internal/cryptlib.h"
+#include "rand_local.h"
+
+typedef struct crng_test_global_st {
+    unsigned char crngt_prev[EVP_MAX_MD_SIZE];
+    RAND_POOL *crngt_pool;
+} CRNG_TEST_GLOBAL;
+
+int (*crngt_get_entropy)(OPENSSL_CTX *, RAND_POOL *, unsigned char *,
+                         unsigned char *, unsigned int *)
+    = &rand_crngt_get_entropy_cb;
+
+static void rand_crng_ossl_ctx_free(void *vcrngt_glob)
+{
+    CRNG_TEST_GLOBAL *crngt_glob = vcrngt_glob;
+
+    rand_pool_free(crngt_glob->crngt_pool);
+    OPENSSL_free(crngt_glob);
+}
+
+static void *rand_crng_ossl_ctx_new(OPENSSL_CTX *ctx)
+{
+    unsigned char buf[CRNGT_BUFSIZ];
+    CRNG_TEST_GLOBAL *crngt_glob = OPENSSL_zalloc(sizeof(*crngt_glob));
+
+    if (crngt_glob == NULL)
+        return NULL;
+
+    if ((crngt_glob->crngt_pool
+         = rand_pool_new(0, 1, CRNGT_BUFSIZ, CRNGT_BUFSIZ)) == NULL) {
+        OPENSSL_free(crngt_glob);
+        return NULL;
+    }
+    if (crngt_get_entropy(ctx, crngt_glob->crngt_pool, buf,
+                          crngt_glob->crngt_prev, NULL)) {
+        OPENSSL_cleanse(buf, sizeof(buf));
+        return crngt_glob;
+    }
+    rand_pool_free(crngt_glob->crngt_pool);
+    OPENSSL_free(crngt_glob);
+    return NULL;
+}
+
+static const OPENSSL_CTX_METHOD rand_crng_ossl_ctx_method = {
+    rand_crng_ossl_ctx_new,
+    rand_crng_ossl_ctx_free,
+};
+
+int rand_crngt_get_entropy_cb(OPENSSL_CTX *ctx,
+                              RAND_POOL *pool,
+                              unsigned char *buf,
+                              unsigned char *md,
+                              unsigned int *md_size)
+{
+    int r;
+    size_t n;
+    unsigned char *p;
+
+    if (pool == NULL)
+        return 0;
+
+    n = rand_pool_acquire_entropy(pool);
+    if (n >= CRNGT_BUFSIZ) {
+        EVP_MD *fmd = EVP_MD_fetch(ctx, "SHA256", "");
+        if (fmd == NULL)
+            return 0;
+        p = rand_pool_detach(pool);
+        r = EVP_Digest(p, CRNGT_BUFSIZ, md, md_size, fmd, NULL);
+        if (r != 0)
+            memcpy(buf, p, CRNGT_BUFSIZ);
+        rand_pool_reattach(pool, p);
+        EVP_MD_free(fmd);
+        return r;
+    }
+    return 0;
+}
+
+size_t rand_crngt_get_entropy(RAND_DRBG *drbg,
+                              unsigned char **pout,
+                              int entropy, size_t min_len, size_t max_len,
+                              int prediction_resistance)
+{
+    unsigned char buf[CRNGT_BUFSIZ], md[EVP_MAX_MD_SIZE];
+    unsigned int sz;
+    RAND_POOL *pool;
+    size_t q, r = 0, s, t = 0;
+    int attempts = 3;
+    CRNG_TEST_GLOBAL *crngt_glob
+        = openssl_ctx_get_data(drbg->libctx, OPENSSL_CTX_RAND_CRNGT_INDEX,
+                               &rand_crng_ossl_ctx_method);
+
+    if (crngt_glob == NULL)
+        return 0;
+
+    if ((pool = rand_pool_new(entropy, 1, min_len, max_len)) == NULL)
+        return 0;
+
+    while ((q = rand_pool_bytes_needed(pool, 1)) > 0 && attempts-- > 0) {
+        s = q > sizeof(buf) ? sizeof(buf) : q;
+        if (!crngt_get_entropy(drbg->libctx, crngt_glob->crngt_pool, buf, md,
+                               &sz)
+            || memcmp(crngt_glob->crngt_prev, md, sz) == 0
+            || !rand_pool_add(pool, buf, s, s * 8))
+            goto err;
+        memcpy(crngt_glob->crngt_prev, md, sz);
+        t += s;
+        attempts++;
+    }
+    r = t;
+    *pout = rand_pool_detach(pool);
+err:
+    OPENSSL_cleanse(buf, sizeof(buf));
+    rand_pool_free(pool);
+    return r;
+}
+
+void rand_crngt_cleanup_entropy(RAND_DRBG *drbg,
+                                unsigned char *out, size_t outlen)
+{
+    OPENSSL_secure_clear_free(out, outlen);
+}