Extensive reorganisation of PRNG handling in FIPS module: all calls

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

diff --git a/crypto/rand/rand_lib.c b/crypto/rand/rand_lib.c
index 513e3389859e9f4a504cbd0796d1df3b88315cd7..ef10dd507eb4ef15c70e12d8c16deb5ff55e5a74 100644 (file)
--- a/crypto/rand/rand_lib.c
+++ b/crypto/rand/rand_lib.c
@@ -60,6 +60,7 @@
 #include <time.h>
 #include "cryptlib.h"
 #include <openssl/rand.h>
+
 #ifndef OPENSSL_NO_ENGINE
 #include <openssl/engine.h>
 #endif
@@ -174,3 +175,70 @@ int RAND_status(void)
                return meth->status();
        return 0;
        }
+
+#ifdef OPENSSL_FIPS
+
+#include <openssl/fips.h>
+#include <openssl/fips_rand.h>
+
+/* FIPS DRBG initialisation code. This sets up the DRBG for use by the
+ * rest of OpenSSL. 
+ */
+
+/* Entropy gatherer: use standard OpenSSL PRNG to seed (this will gather
+ * entropy internally through RAND_poll().
+ */
+
+static size_t drbg_get_entropy(DRBG_CTX *ctx, unsigned char **pout,
+                                int entropy, size_t min_len, size_t max_len)
+        {
+       *pout = OPENSSL_malloc(min_len);
+       if (!*pout)
+               return 0;
+       if (RAND_SSLeay()->bytes(*pout, min_len) <= 0)
+               {
+               OPENSSL_free(*pout);
+               *pout = NULL;
+               return 0;
+               }
+        return min_len;
+        }
+
+static void drbg_free_entropy(DRBG_CTX *ctx, unsigned char *out, size_t olen)
+       {
+       OPENSSL_cleanse(out, olen);
+       OPENSSL_free(out);
+       }
+
+/* RAND_add() and RAND_seed() pass through to OpenSSL PRNG so it is 
+ * correctly seeded by RAND_poll().
+ */
+
+static int drbg_rand_add(DRBG_CTX *ctx, const void *in, int inlen,
+                               double entropy)
+       {
+       return RAND_SSLeay()->add(in, inlen, entropy);
+       }
+
+static int drbg_rand_seed(DRBG_CTX *ctx, const void *in, int inlen)
+       {
+       return RAND_SSLeay()->seed(in, inlen);
+       }
+
+int RAND_init_fips(void)
+       {
+       DRBG_CTX *dctx;
+       unsigned char pers[16] = {0,0,0};
+       dctx = FIPS_get_default_drbg();
+        FIPS_drbg_init(dctx, NID_aes_256_ctr, DRBG_FLAG_CTR_USE_DF);
+        FIPS_drbg_set_callbacks(dctx,
+                               drbg_get_entropy, drbg_free_entropy,
+                               drbg_get_entropy, drbg_free_entropy);
+       FIPS_drbg_set_rand_callbacks(dctx, 0, 0,
+                                       drbg_rand_seed, drbg_rand_add);
+        FIPS_drbg_instantiate(dctx, pers, sizeof(pers));
+        FIPS_rand_set_method(FIPS_drbg_method());
+       return 1;
+       }
+
+#endif