X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=fips%2Frand%2Ffips_drbg_lib.c;h=95c73e191d32fc468d620df0f4a0bada8a62f67a;hp=1c8712e7a5255d3d36f94b4a4ad8dc0d670d4ee6;hb=cf61940534836ebd8d8a13bae0dd2cbd273a3d49;hpb=1b76fac5ae55d2d307f635af4775a7c9149c8551

diff --git a/fips/rand/fips_drbg_lib.c b/fips/rand/fips_drbg_lib.c
index 1c8712e7a5..95c73e191d 100644
--- a/fips/rand/fips_drbg_lib.c
+++ b/fips/rand/fips_drbg_lib.c
@@ -1,4 +1,3 @@
-/* fips/rand/fips_drbg_lib.c */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project.
  */
@@ -55,33 +54,58 @@
 
 #include <string.h>
 #include <openssl/crypto.h>
-#include <openssl/evp.h>
-#include <openssl/aes.h>
 #include <openssl/err.h>
 #include <openssl/fips_rand.h>
 #include "fips_rand_lcl.h"
 
 /* Support framework for SP800-90 DRBGs */
 
-static int fips_drbg_init(DRBG_CTX *dctx, int type, unsigned int flags)
+int FIPS_drbg_init(DRBG_CTX *dctx, int type, unsigned int flags)
 	{
 	int rv;
 	memset(dctx, 0, sizeof(DRBG_CTX));
 	dctx->status = DRBG_STATUS_UNINITIALISED;
-	dctx->flags = flags;
+	dctx->xflags = flags;
 	dctx->type = type;
 
+	dctx->iflags = 0;
+	dctx->entropy_blocklen = 0;
+	dctx->health_check_cnt = 0;
+	dctx->health_check_interval = DRBG_HEALTH_INTERVAL;
+
 	rv = fips_drbg_hash_init(dctx);
 
 	if (rv == -2)
 		rv = fips_drbg_ctr_init(dctx);
+	if (rv == -2)
+		rv = fips_drbg_hmac_init(dctx);
+	if (rv == -2)
+		rv = fips_drbg_ec_init(dctx);
+
+	if (rv <= 0)
+		{
+		if (rv == -2)
+			FIPSerr(FIPS_F_FIPS_DRBG_INIT, FIPS_R_UNSUPPORTED_DRBG_TYPE);
+		else
+			FIPSerr(FIPS_F_FIPS_DRBG_INIT, FIPS_R_ERROR_INITIALISING_DRBG);
+		}
+
+	/* If not in test mode run selftests on DRBG of the same type */
+
+	if (!(dctx->xflags & DRBG_FLAG_TEST))
+		{
+		if (!FIPS_drbg_health_check(dctx))
+			{
+			FIPSerr(FIPS_F_FIPS_DRBG_INIT, FIPS_R_SELFTEST_FAILURE);
+			return 0;
+			}
+		}
 
 	return rv;
 	}
 
 DRBG_CTX *FIPS_drbg_new(int type, unsigned int flags)
 	{
-	int rv;
 	DRBG_CTX *dctx;
 	dctx = OPENSSL_malloc(sizeof(DRBG_CTX));
 	if (!dctx)
@@ -89,33 +113,77 @@ DRBG_CTX *FIPS_drbg_new(int type, unsigned int flags)
 		FIPSerr(FIPS_F_FIPS_DRBG_NEW, ERR_R_MALLOC_FAILURE);
 		return NULL;
 		}
-	rv = fips_drbg_init(dctx, type, flags);
 
-	if (rv <= 0)
+	if (type == 0)
 		{
-		if (rv == -2)
-			FIPSerr(FIPS_F_FIPS_DRBG_NEW, FIPS_R_UNSUPPORTED_DRBG_TYPE);
-		else
-			FIPSerr(FIPS_F_FIPS_DRBG_NEW, FIPS_R_ERROR_INITIALISING_DRBG);
+		memset(dctx, 0, sizeof(DRBG_CTX));
+		dctx->type = 0;
+		dctx->status = DRBG_STATUS_UNINITIALISED;
+		return dctx;
+		}
 
+	if (FIPS_drbg_init(dctx, type, flags) <= 0)
+		{
 		OPENSSL_free(dctx);
 		return NULL;
 		}
+		
 	return dctx;
 	}
 
 void FIPS_drbg_free(DRBG_CTX *dctx)
 	{
-	dctx->uninstantiate(dctx);
-	OPENSSL_cleanse(dctx, sizeof(DRBG_CTX));
+	if (dctx->uninstantiate)
+		dctx->uninstantiate(dctx);
+	OPENSSL_cleanse(&dctx->d, sizeof(dctx->d));
 	OPENSSL_free(dctx);
 	}
 
+static size_t fips_get_entropy(DRBG_CTX *dctx, unsigned char **pout,
+				int entropy, size_t min_len, size_t max_len)
+	{
+	unsigned char *tout, *p;
+	size_t bl = dctx->entropy_blocklen, rv;
+	if (dctx->xflags & DRBG_FLAG_TEST || !bl)
+		return dctx->get_entropy(dctx, pout, entropy, min_len, max_len);
+	rv = dctx->get_entropy(dctx, &tout, entropy + bl,
+				min_len + bl, max_len + bl);
+	*pout = tout + bl;
+	if (rv < (min_len + bl) || (rv % bl))
+		return 0;
+	/* Compare consecutive blocks for continuous PRNG test */
+	for (p = tout; p < tout + rv - bl; p += bl)
+		{
+		if (!memcmp(p, p + bl, bl))
+			{
+			FIPSerr(FIPS_F_FIPS_GET_ENTROPY, FIPS_R_ENTROPY_SOURCE_STUCK);
+			return 0;
+			}
+		}
+	rv -= bl;
+	if (rv > max_len)
+		return max_len;
+	return rv;
+	}
+
+static void fips_cleanup_entropy(DRBG_CTX *dctx,
+					unsigned char *out, size_t olen)
+	{
+	size_t bl;
+	if (dctx->xflags & DRBG_FLAG_TEST)
+		bl = 0;
+	else
+		bl = dctx->entropy_blocklen;
+	/* Call cleanup with original arguments */
+	dctx->cleanup_entropy(dctx, out - bl, olen + bl);
+	}
+
+
 int FIPS_drbg_instantiate(DRBG_CTX *dctx,
-				int strength,
 				const unsigned char *pers, size_t perslen)
 	{
-	size_t entlen, noncelen;
+	size_t entlen = 0, noncelen = 0;
+	unsigned char *nonce = NULL, *entropy = NULL;
 
 #if 0
 	/* Put here so error script picks them up */
@@ -145,15 +213,9 @@ int FIPS_drbg_instantiate(DRBG_CTX *dctx,
 		goto end;
 		}
 
-	if (strength > dctx->strength)
-		{
-		r = FIPS_R_INSUFFICIENT_SECURITY_STRENGTH;
-		goto end;
-		}
-
 	dctx->status = DRBG_STATUS_ERROR;
 
-	entlen = dctx->get_entropy(dctx, dctx->entropy, dctx->strength,
+	entlen = fips_get_entropy(dctx, &entropy, dctx->strength,
 				dctx->min_entropy, dctx->max_entropy);
 
 	if (entlen < dctx->min_entropy || entlen > dctx->max_entropy)
@@ -164,8 +226,7 @@ int FIPS_drbg_instantiate(DRBG_CTX *dctx,
 
 	if (dctx->max_nonce > 0)
 		{
-
-		noncelen = dctx->get_nonce(dctx, dctx->nonce,
+		noncelen = dctx->get_nonce(dctx, &nonce,
 					dctx->strength / 2,
 					dctx->min_nonce, dctx->max_nonce);
 
@@ -176,12 +237,10 @@ int FIPS_drbg_instantiate(DRBG_CTX *dctx,
 			}
 
 		}
-	else
-		noncelen = 0;
 
 	if (!dctx->instantiate(dctx, 
-				dctx->entropy, entlen,
-				dctx->nonce, noncelen,
+				entropy, entlen,
+				nonce, noncelen,
 				pers, perslen))
 		{
 		r = FIPS_R_ERROR_INSTANTIATING_DRBG;
@@ -190,29 +249,32 @@ int FIPS_drbg_instantiate(DRBG_CTX *dctx,
 
 
 	dctx->status = DRBG_STATUS_READY;
-	dctx->reseed_counter = 1;
-	/* Initial test value for reseed interval */
-	dctx->reseed_interval = 1<<24;
+	if (!(dctx->iflags & DRBG_CUSTOM_RESEED))
+		dctx->reseed_counter = 1;
 
 	end:
 
-	OPENSSL_cleanse(dctx->entropy, sizeof(dctx->entropy));
-	OPENSSL_cleanse(dctx->nonce, sizeof(dctx->nonce));
+	if (entropy && dctx->cleanup_entropy)
+		fips_cleanup_entropy(dctx, entropy, entlen);
+
+	if (nonce && dctx->cleanup_nonce)
+		dctx->cleanup_nonce(dctx, nonce, noncelen);
 
 	if (dctx->status == DRBG_STATUS_READY)
 		return 1;
 
-	if (r && !(dctx->flags & DRBG_FLAG_TEST))
+	if (r && !(dctx->iflags & DRBG_FLAG_NOERR))
 		FIPSerr(FIPS_F_FIPS_DRBG_INSTANTIATE, r);
 
 	return 0;
 
 	}
 
-int FIPS_drbg_reseed(DRBG_CTX *dctx,
-			const unsigned char *adin, size_t adinlen)
+static int drbg_reseed(DRBG_CTX *dctx,
+			const unsigned char *adin, size_t adinlen, int hcheck)
 	{
-	size_t entlen;
+	unsigned char *entropy = NULL;
+	size_t entlen = 0;
 	int r = 0;
 
 #if 0
@@ -238,8 +300,19 @@ int FIPS_drbg_reseed(DRBG_CTX *dctx,
 		}
 
 	dctx->status = DRBG_STATUS_ERROR;
+	/* Peform health check on all reseed operations if not a prediction
+	 * resistance request and not in test mode.
+	 */
+	if (hcheck && !(dctx->xflags & DRBG_FLAG_TEST))
+		{
+		if (!FIPS_drbg_health_check(dctx))
+			{
+			r = FIPS_R_SELFTEST_FAILURE;
+			goto end;
+			}
+		}
 
-	entlen = dctx->get_entropy(dctx, dctx->entropy, dctx->strength,
+	entlen = fips_get_entropy(dctx, &entropy, dctx->strength,
 				dctx->min_entropy, dctx->max_entropy);
 
 	if (entlen < dctx->min_entropy || entlen > dctx->max_entropy)
@@ -248,44 +321,90 @@ int FIPS_drbg_reseed(DRBG_CTX *dctx,
 		goto end;
 		}
 
-	if (!dctx->reseed(dctx, dctx->entropy, entlen, adin, adinlen))
+	if (!dctx->reseed(dctx, entropy, entlen, adin, adinlen))
 		goto end;
 
 	dctx->status = DRBG_STATUS_READY;
-	dctx->reseed_counter = 1;
+	if (!(dctx->iflags & DRBG_CUSTOM_RESEED))
+		dctx->reseed_counter = 1;
 	end:
-	OPENSSL_cleanse(dctx->entropy, sizeof(dctx->entropy));
+
+	if (entropy && dctx->cleanup_entropy)
+		fips_cleanup_entropy(dctx, entropy, entlen);
 
 	if (dctx->status == DRBG_STATUS_READY)
 		return 1;
 
-	if (r && !(dctx->flags & DRBG_FLAG_TEST))
+	if (r && !(dctx->iflags & DRBG_FLAG_NOERR))
 		FIPSerr(FIPS_F_FIPS_DRBG_RESEED, r);
 
 	return 0;
 	}
 
+int FIPS_drbg_reseed(DRBG_CTX *dctx,
+			const unsigned char *adin, size_t adinlen)
+	{
+	return drbg_reseed(dctx, adin, adinlen, 1);
+	}
+
+static int fips_drbg_check(DRBG_CTX *dctx)
+	{
+	if (dctx->xflags & DRBG_FLAG_TEST)
+		return 1;
+	dctx->health_check_cnt++;
+	if (dctx->health_check_cnt >= dctx->health_check_interval)
+		{
+		if (!FIPS_drbg_health_check(dctx))
+			{
+			FIPSerr(FIPS_F_FIPS_DRBG_CHECK, FIPS_R_SELFTEST_FAILURE);
+			return 0;
+			}
+		}
+	return 1;
+	}
 
 int FIPS_drbg_generate(DRBG_CTX *dctx, unsigned char *out, size_t outlen,
-			int strength, int prediction_resistance,
+			int prediction_resistance,
 			const unsigned char *adin, size_t adinlen)
 	{
 	int r = 0;
+
+	if (!fips_drbg_check(dctx))
+		return 0;
+
+	if (dctx->status != DRBG_STATUS_READY
+		&& dctx->status != DRBG_STATUS_RESEED)
+		{
+		if (dctx->status == DRBG_STATUS_ERROR)
+			r = FIPS_R_IN_ERROR_STATE;
+		else if(dctx->status == DRBG_STATUS_UNINITIALISED)
+			r = FIPS_R_NOT_INSTANTIATED;
+		goto end;
+		}
+
 	if (outlen > dctx->max_request)
 		{
 		r = FIPS_R_REQUEST_TOO_LARGE_FOR_DRBG;
 		return 0;
 		}
 
-	if (strength > dctx->strength)
+	if (adinlen > dctx->max_adin)
 		{
-		r = FIPS_R_INSUFFICIENT_SECURITY_STRENGTH;
+		r = FIPS_R_ADDITIONAL_INPUT_TOO_LONG;
 		goto end;
 		}
 
+	if (dctx->iflags & DRBG_CUSTOM_RESEED)
+		dctx->generate(dctx, NULL, outlen, NULL, 0);
+	else if (dctx->reseed_counter >= dctx->reseed_interval)
+		dctx->status = DRBG_STATUS_RESEED;
+
 	if (dctx->status == DRBG_STATUS_RESEED || prediction_resistance)
 		{
-		if (!FIPS_drbg_reseed(dctx, adin, adinlen))
+		/* If prediction resistance request don't do health check */
+		int hcheck = prediction_resistance ? 0 : 1;
+		
+		if (!drbg_reseed(dctx, adin, adinlen, hcheck))
 			{
 			r = FIPS_R_RESEED_ERROR;
 			goto end;
@@ -293,29 +412,25 @@ int FIPS_drbg_generate(DRBG_CTX *dctx, unsigned char *out, size_t outlen,
 		adin = NULL;
 		adinlen = 0;
 		}
-	if (dctx->status != DRBG_STATUS_READY)
-		{
-		if (dctx->status == DRBG_STATUS_ERROR)
-			r = FIPS_R_IN_ERROR_STATE;
-		else if(dctx->status == DRBG_STATUS_UNINITIALISED)
-			r = FIPS_R_NOT_INSTANTIATED;
-		goto end;
-		}
+
 	if (!dctx->generate(dctx, out, outlen, adin, adinlen))
 		{
 		r = FIPS_R_GENERATE_ERROR;
 		dctx->status = DRBG_STATUS_ERROR;
 		goto end;
 		}
-	if (dctx->reseed_counter > dctx->reseed_interval)
-		dctx->status = DRBG_STATUS_RESEED;
-	else
-		dctx->reseed_counter++;
+	if (!(dctx->iflags & DRBG_CUSTOM_RESEED))
+		{
+		if (dctx->reseed_counter >= dctx->reseed_interval)
+			dctx->status = DRBG_STATUS_RESEED;
+		else
+			dctx->reseed_counter++;
+		}
 
 	end:
 	if (r)
 		{
-		if (!(dctx->flags & DRBG_FLAG_TEST))
+		if (!(dctx->iflags & DRBG_FLAG_NOERR))
 			FIPSerr(FIPS_F_FIPS_DRBG_GENERATE, r);
 		return 0;
 		}
@@ -325,28 +440,52 @@ int FIPS_drbg_generate(DRBG_CTX *dctx, unsigned char *out, size_t outlen,
 
 int FIPS_drbg_uninstantiate(DRBG_CTX *dctx)
 	{
-	int save_type, save_flags, rv;
-	save_type = dctx->type;
-	save_flags = dctx->flags;
-	rv = dctx->uninstantiate(dctx);
-	OPENSSL_cleanse(dctx, sizeof(DRBG_CTX));
+	int rv;
+	if (!dctx->uninstantiate)
+		rv = 1;
+	else
+		rv = dctx->uninstantiate(dctx);
+	/* Although we'd like to cleanse here we can't because we have to
+	 * test the uninstantiate really zeroes the data.
+	 */
+	memset(&dctx->d, 0, sizeof(dctx->d));
+	dctx->status = DRBG_STATUS_UNINITIALISED;
 	/* If method has problems uninstantiating, return error */
-	if (rv <= 0)
-		return rv;
-	return fips_drbg_init(dctx, save_type, save_flags);
+	return rv;
 	}
 
-int FIPS_drbg_set_test_mode(DRBG_CTX *dctx,
-	size_t (*get_entropy)(DRBG_CTX *ctx, unsigned char *out,
+int FIPS_drbg_set_callbacks(DRBG_CTX *dctx,
+	size_t (*get_entropy)(DRBG_CTX *ctx, unsigned char **pout,
+				int entropy, size_t min_len, size_t max_len),
+	void (*cleanup_entropy)(DRBG_CTX *ctx, unsigned char *out, size_t olen),
+	size_t entropy_blocklen,
+	size_t (*get_nonce)(DRBG_CTX *ctx, unsigned char **pout,
 				int entropy, size_t min_len, size_t max_len),
-	size_t (*get_nonce)(DRBG_CTX *ctx, unsigned char *out,
-				int entropy, size_t min_len, size_t max_len))
+	void (*cleanup_nonce)(DRBG_CTX *ctx, unsigned char *out, size_t olen))
 	{
 	if (dctx->status != DRBG_STATUS_UNINITIALISED)
 		return 0;
-	dctx->flags |= DRBG_FLAG_TEST;
+	dctx->entropy_blocklen = entropy_blocklen;
 	dctx->get_entropy = get_entropy;
+	dctx->cleanup_entropy = cleanup_entropy;
 	dctx->get_nonce = get_nonce;
+	dctx->cleanup_nonce = cleanup_nonce;
+	return 1;
+	}
+
+int FIPS_drbg_set_rand_callbacks(DRBG_CTX *dctx,
+	size_t (*get_adin)(DRBG_CTX *ctx, unsigned char **pout),
+	void (*cleanup_adin)(DRBG_CTX *ctx, unsigned char *out, size_t olen),
+	int (*rand_seed_cb)(DRBG_CTX *ctx, const void *buf, int num),
+	int (*rand_add_cb)(DRBG_CTX *ctx,
+				const void *buf, int num, double entropy))
+	{
+	if (dctx->status != DRBG_STATUS_UNINITIALISED)
+		return 0;
+	dctx->get_adin = get_adin;
+	dctx->cleanup_adin = cleanup_adin;
+	dctx->rand_seed_cb = rand_seed_cb;
+	dctx->rand_add_cb = rand_add_cb;
 	return 1;
 	}
 
@@ -369,3 +508,47 @@ int FIPS_drbg_get_strength(DRBG_CTX *dctx)
 	{
 	return dctx->strength;
 	}
+
+void FIPS_drbg_set_check_interval(DRBG_CTX *dctx, int interval)
+	{
+	dctx->health_check_interval = interval;
+	}
+
+void FIPS_drbg_set_reseed_interval(DRBG_CTX *dctx, int interval)
+	{
+	dctx->reseed_interval = interval;
+	}
+
+static int drbg_stick = 0;
+
+void FIPS_drbg_stick(void)
+	{
+	drbg_stick = 1;
+	}
+
+/* Continuous DRBG utility function */
+int fips_drbg_cprng_test(DRBG_CTX *dctx, const unsigned char *out)
+	{
+	/* No CPRNG in test mode */
+	if (dctx->xflags & DRBG_FLAG_TEST)
+		return 1;
+	/* Check block is valid: should never happen */
+	if (dctx->lb_valid == 0)
+		{
+		FIPSerr(FIPS_F_FIPS_DRBG_CPRNG_TEST, FIPS_R_INTERNAL_ERROR);
+		fips_set_selftest_fail();
+		return 0;
+		}
+	if (drbg_stick)
+		memcpy(dctx->lb, out, dctx->blocklength);
+	/* Check against last block: fail if match */
+	if (!memcmp(dctx->lb, out, dctx->blocklength))
+		{
+		FIPSerr(FIPS_F_FIPS_DRBG_CPRNG_TEST, FIPS_R_DRBG_STUCK);
+		fips_set_selftest_fail();
+		return 0;
+		}
+	/* Save last block for next comparison */
+	memcpy(dctx->lb, out, dctx->blocklength);
+	return 1;
+	}