Use rdrand as additional entropy source.

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

diff --git a/crypto/rand/rand_lib.c b/crypto/rand/rand_lib.c
index 38cea799380cc49af62e69fcdb4e8b51fd072dd5..4aa6486c8102c9e07d64cfd29ca57c76db0ba9ff 100644 (file)
--- a/crypto/rand/rand_lib.c
+++ b/crypto/rand/rand_lib.c
@@ -60,45 +60,87 @@
 #include <time.h>
 #include "cryptlib.h"
 #include <openssl/rand.h>
+
+#ifndef OPENSSL_NO_ENGINE
 #include <openssl/engine.h>
+#endif
 
-static ENGINE *rand_engine=NULL;
+#ifdef OPENSSL_FIPS
+#include <openssl/fips.h>
+#include <openssl/fips_rand.h>
+#endif
 
-#if 0
-void RAND_set_rand_method(RAND_METHOD *meth)
-       {
-       rand_meth=meth;
-       }
-#else
-int RAND_set_rand_method(ENGINE *engine)
+#ifndef OPENSSL_NO_ENGINE
+/* non-NULL if default_RAND_meth is ENGINE-provided */
+static ENGINE *funct_ref =NULL;
+#endif
+static const RAND_METHOD *default_RAND_meth = NULL;
+
+int RAND_set_rand_method(const RAND_METHOD *meth)
        {
-       ENGINE *mtmp;
-       mtmp = rand_engine;
-       if (!ENGINE_init(engine))
-               return 0;
-       rand_engine = engine;
-       /* SHOULD ERROR CHECK THIS!!! */
-       ENGINE_finish(mtmp);
+#ifndef OPENSSL_NO_ENGINE
+       if(funct_ref)
+               {
+               ENGINE_finish(funct_ref);
+               funct_ref = NULL;
+               }
+#endif
+       default_RAND_meth = meth;
        return 1;
        }
-#endif
 
 const RAND_METHOD *RAND_get_rand_method(void)
        {
-       if (rand_engine == NULL
-               && (rand_engine = ENGINE_get_default_RAND()) == NULL)
+       if (!default_RAND_meth)
                {
-               RANDerr(RAND_F_RAND_GET_RAND_METHOD,ERR_LIB_ENGINE);
-               return NULL;
+#ifndef OPENSSL_NO_ENGINE
+               ENGINE *e = ENGINE_get_default_RAND();
+               if(e)
+                       {
+                       default_RAND_meth = ENGINE_get_RAND(e);
+                       if(!default_RAND_meth)
+                               {
+                               ENGINE_finish(e);
+                               e = NULL;
+                               }
+                       }
+               if(e)
+                       funct_ref = e;
+               else
+#endif
+                       default_RAND_meth = RAND_SSLeay();
                }
-       return ENGINE_get_RAND(rand_engine);
+       return default_RAND_meth;
        }
 
+#ifndef OPENSSL_NO_ENGINE
+int RAND_set_rand_engine(ENGINE *engine)
+       {
+       const RAND_METHOD *tmp_meth = NULL;
+       if(engine)
+               {
+               if(!ENGINE_init(engine))
+                       return 0;
+               tmp_meth = ENGINE_get_RAND(engine);
+               if(!tmp_meth)
+                       {
+                       ENGINE_finish(engine);
+                       return 0;
+                       }
+               }
+       /* This function releases any prior ENGINE so call it first */
+       RAND_set_rand_method(tmp_meth);
+       funct_ref = engine;
+       return 1;
+       }
+#endif
+
 void RAND_cleanup(void)
        {
        const RAND_METHOD *meth = RAND_get_rand_method();
        if (meth && meth->cleanup)
                meth->cleanup();
+       RAND_set_rand_method(NULL);
        }
 
 void RAND_seed(const void *buf, int num)
@@ -138,3 +180,93 @@ int RAND_status(void)
                return meth->status();
        return 0;
        }
+
+#ifdef OPENSSL_FIPS
+
+/* 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)
+        {
+       /* Round up request to multiple of block size */
+       min_len = ((min_len + 19) / 20) * 20;
+       *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)
+       {
+       if (out)
+               {
+               OPENSSL_cleanse(out, olen);
+               OPENSSL_free(out);
+               }
+       }
+
+/* Set "additional input" when generating random data. This uses the
+ * current PID, a time value and a counter.
+ */
+
+static size_t drbg_get_adin(DRBG_CTX *ctx, unsigned char **pout)
+       {
+       /* Use of static variables is OK as this happens under a lock */
+       static unsigned char buf[16];
+       static unsigned long counter;
+       FIPS_get_timevec(buf, &counter);
+       rand_hw_xor(buf, sizeof(buf));
+       *pout = buf;
+       return sizeof(buf);
+       }
+
+/* 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;
+       size_t plen;
+       unsigned char pers[32], *p;
+       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, 20,
+                               drbg_get_entropy, drbg_free_entropy);
+       FIPS_drbg_set_rand_callbacks(dctx, drbg_get_adin, 0,
+                                       drbg_rand_seed, drbg_rand_add);
+       /* Personalisation string: a string followed by date time vector */
+       strcpy((char *)pers, "OpenSSL DRBG2.0");
+       plen = drbg_get_adin(dctx, &p);
+       memcpy(pers + 16, p, plen);
+
+        FIPS_drbg_instantiate(dctx, pers, sizeof(pers));
+        FIPS_rand_set_method(FIPS_drbg_method());
+       return 1;
+       }
+
+#endif