Simon Cooksey
Pinned to some recent date
Diff: features/mbedtls/src/ctr_drbg.c
- Revision:
- 0:fb7af294d5d9
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/features/mbedtls/src/ctr_drbg.c Thu Nov 17 16:43:53 2016 +0000
@@ -0,0 +1,593 @@
+/*
+ * CTR_DRBG implementation based on AES-256 (NIST SP 800-90)
+ *
+ * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * This file is part of mbed TLS (https://tls.mbed.org)
+ */
+/*
+ * The NIST SP 800-90 DRBGs are described in the following publucation.
+ *
+ * http://csrc.nist.gov/publications/nistpubs/800-90/SP800-90revised_March2007.pdf
+ */
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#if defined(MBEDTLS_CTR_DRBG_C)
+
+#include "mbedtls/ctr_drbg.h"
+
+#include <string.h>
+
+#if defined(MBEDTLS_FS_IO)
+#include <stdio.h>
+#endif
+
+#if defined(MBEDTLS_SELF_TEST)
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#else
+#include <stdio.h>
+#define mbedtls_printf printf
+#endif /* MBEDTLS_PLATFORM_C */
+#endif /* MBEDTLS_SELF_TEST */
+
+/* Implementation that should never be optimized out by the compiler */
+static void mbedtls_zeroize( void *v, size_t n ) {
+ volatile unsigned char *p = v; while( n-- ) *p++ = 0;
+}
+
+/*
+ * CTR_DRBG context initialization
+ */
+void mbedtls_ctr_drbg_init( mbedtls_ctr_drbg_context *ctx )
+{
+ memset( ctx, 0, sizeof( mbedtls_ctr_drbg_context ) );
+
+#if defined(MBEDTLS_THREADING_C)
+ mbedtls_mutex_init( &ctx->mutex );
+#endif
+}
+
+/*
+ * Non-public function wrapped by mbedtls_ctr_drbg_seed(). Necessary to allow
+ * NIST tests to succeed (which require known length fixed entropy)
+ */
+int mbedtls_ctr_drbg_seed_entropy_len(
+ mbedtls_ctr_drbg_context *ctx,
+ int (*f_entropy)(void *, unsigned char *, size_t),
+ void *p_entropy,
+ const unsigned char *custom,
+ size_t len,
+ size_t entropy_len )
+{
+ int ret;
+ unsigned char key[MBEDTLS_CTR_DRBG_KEYSIZE];
+
+ memset( key, 0, MBEDTLS_CTR_DRBG_KEYSIZE );
+
+ mbedtls_aes_init( &ctx->aes_ctx );
+
+ ctx->f_entropy = f_entropy;
+ ctx->p_entropy = p_entropy;
+
+ ctx->entropy_len = entropy_len;
+ ctx->reseed_interval = MBEDTLS_CTR_DRBG_RESEED_INTERVAL;
+
+ /*
+ * Initialize with an empty key
+ */
+ mbedtls_aes_setkey_enc( &ctx->aes_ctx, key, MBEDTLS_CTR_DRBG_KEYBITS );
+
+ if( ( ret = mbedtls_ctr_drbg_reseed( ctx, custom, len ) ) != 0 )
+ return( ret );
+
+ return( 0 );
+}
+
+int mbedtls_ctr_drbg_seed( mbedtls_ctr_drbg_context *ctx,
+ int (*f_entropy)(void *, unsigned char *, size_t),
+ void *p_entropy,
+ const unsigned char *custom,
+ size_t len )
+{
+ return( mbedtls_ctr_drbg_seed_entropy_len( ctx, f_entropy, p_entropy, custom, len,
+ MBEDTLS_CTR_DRBG_ENTROPY_LEN ) );
+}
+
+void mbedtls_ctr_drbg_free( mbedtls_ctr_drbg_context *ctx )
+{
+ if( ctx == NULL )
+ return;
+
+#if defined(MBEDTLS_THREADING_C)
+ mbedtls_mutex_free( &ctx->mutex );
+#endif
+ mbedtls_aes_free( &ctx->aes_ctx );
+ mbedtls_zeroize( ctx, sizeof( mbedtls_ctr_drbg_context ) );
+}
+
+void mbedtls_ctr_drbg_set_prediction_resistance( mbedtls_ctr_drbg_context *ctx, int resistance )
+{
+ ctx->prediction_resistance = resistance;
+}
+
+void mbedtls_ctr_drbg_set_entropy_len( mbedtls_ctr_drbg_context *ctx, size_t len )
+{
+ ctx->entropy_len = len;
+}
+
+void mbedtls_ctr_drbg_set_reseed_interval( mbedtls_ctr_drbg_context *ctx, int interval )
+{
+ ctx->reseed_interval = interval;
+}
+
+static int block_cipher_df( unsigned char *output,
+ const unsigned char *data, size_t data_len )
+{
+ unsigned char buf[MBEDTLS_CTR_DRBG_MAX_SEED_INPUT + MBEDTLS_CTR_DRBG_BLOCKSIZE + 16];
+ unsigned char tmp[MBEDTLS_CTR_DRBG_SEEDLEN];
+ unsigned char key[MBEDTLS_CTR_DRBG_KEYSIZE];
+ unsigned char chain[MBEDTLS_CTR_DRBG_BLOCKSIZE];
+ unsigned char *p, *iv;
+ mbedtls_aes_context aes_ctx;
+
+ int i, j;
+ size_t buf_len, use_len;
+
+ if( data_len > MBEDTLS_CTR_DRBG_MAX_SEED_INPUT )
+ return( MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG );
+
+ memset( buf, 0, MBEDTLS_CTR_DRBG_MAX_SEED_INPUT + MBEDTLS_CTR_DRBG_BLOCKSIZE + 16 );
+ mbedtls_aes_init( &aes_ctx );
+
+ /*
+ * Construct IV (16 bytes) and S in buffer
+ * IV = Counter (in 32-bits) padded to 16 with zeroes
+ * S = Length input string (in 32-bits) || Length of output (in 32-bits) ||
+ * data || 0x80
+ * (Total is padded to a multiple of 16-bytes with zeroes)
+ */
+ p = buf + MBEDTLS_CTR_DRBG_BLOCKSIZE;
+ *p++ = ( data_len >> 24 ) & 0xff;
+ *p++ = ( data_len >> 16 ) & 0xff;
+ *p++ = ( data_len >> 8 ) & 0xff;
+ *p++ = ( data_len ) & 0xff;
+ p += 3;
+ *p++ = MBEDTLS_CTR_DRBG_SEEDLEN;
+ memcpy( p, data, data_len );
+ p[data_len] = 0x80;
+
+ buf_len = MBEDTLS_CTR_DRBG_BLOCKSIZE + 8 + data_len + 1;
+
+ for( i = 0; i < MBEDTLS_CTR_DRBG_KEYSIZE; i++ )
+ key[i] = i;
+
+ mbedtls_aes_setkey_enc( &aes_ctx, key, MBEDTLS_CTR_DRBG_KEYBITS );
+
+ /*
+ * Reduce data to MBEDTLS_CTR_DRBG_SEEDLEN bytes of data
+ */
+ for( j = 0; j < MBEDTLS_CTR_DRBG_SEEDLEN; j += MBEDTLS_CTR_DRBG_BLOCKSIZE )
+ {
+ p = buf;
+ memset( chain, 0, MBEDTLS_CTR_DRBG_BLOCKSIZE );
+ use_len = buf_len;
+
+ while( use_len > 0 )
+ {
+ for( i = 0; i < MBEDTLS_CTR_DRBG_BLOCKSIZE; i++ )
+ chain[i] ^= p[i];
+ p += MBEDTLS_CTR_DRBG_BLOCKSIZE;
+ use_len -= ( use_len >= MBEDTLS_CTR_DRBG_BLOCKSIZE ) ?
+ MBEDTLS_CTR_DRBG_BLOCKSIZE : use_len;
+
+ mbedtls_aes_crypt_ecb( &aes_ctx, MBEDTLS_AES_ENCRYPT, chain, chain );
+ }
+
+ memcpy( tmp + j, chain, MBEDTLS_CTR_DRBG_BLOCKSIZE );
+
+ /*
+ * Update IV
+ */
+ buf[3]++;
+ }
+
+ /*
+ * Do final encryption with reduced data
+ */
+ mbedtls_aes_setkey_enc( &aes_ctx, tmp, MBEDTLS_CTR_DRBG_KEYBITS );
+ iv = tmp + MBEDTLS_CTR_DRBG_KEYSIZE;
+ p = output;
+
+ for( j = 0; j < MBEDTLS_CTR_DRBG_SEEDLEN; j += MBEDTLS_CTR_DRBG_BLOCKSIZE )
+ {
+ mbedtls_aes_crypt_ecb( &aes_ctx, MBEDTLS_AES_ENCRYPT, iv, iv );
+ memcpy( p, iv, MBEDTLS_CTR_DRBG_BLOCKSIZE );
+ p += MBEDTLS_CTR_DRBG_BLOCKSIZE;
+ }
+
+ mbedtls_aes_free( &aes_ctx );
+
+ return( 0 );
+}
+
+static int ctr_drbg_update_internal( mbedtls_ctr_drbg_context *ctx,
+ const unsigned char data[MBEDTLS_CTR_DRBG_SEEDLEN] )
+{
+ unsigned char tmp[MBEDTLS_CTR_DRBG_SEEDLEN];
+ unsigned char *p = tmp;
+ int i, j;
+
+ memset( tmp, 0, MBEDTLS_CTR_DRBG_SEEDLEN );
+
+ for( j = 0; j < MBEDTLS_CTR_DRBG_SEEDLEN; j += MBEDTLS_CTR_DRBG_BLOCKSIZE )
+ {
+ /*
+ * Increase counter
+ */
+ for( i = MBEDTLS_CTR_DRBG_BLOCKSIZE; i > 0; i-- )
+ if( ++ctx->counter[i - 1] != 0 )
+ break;
+
+ /*
+ * Crypt counter block
+ */
+ mbedtls_aes_crypt_ecb( &ctx->aes_ctx, MBEDTLS_AES_ENCRYPT, ctx->counter, p );
+
+ p += MBEDTLS_CTR_DRBG_BLOCKSIZE;
+ }
+
+ for( i = 0; i < MBEDTLS_CTR_DRBG_SEEDLEN; i++ )
+ tmp[i] ^= data[i];
+
+ /*
+ * Update key and counter
+ */
+ mbedtls_aes_setkey_enc( &ctx->aes_ctx, tmp, MBEDTLS_CTR_DRBG_KEYBITS );
+ memcpy( ctx->counter, tmp + MBEDTLS_CTR_DRBG_KEYSIZE, MBEDTLS_CTR_DRBG_BLOCKSIZE );
+
+ return( 0 );
+}
+
+void mbedtls_ctr_drbg_update( mbedtls_ctr_drbg_context *ctx,
+ const unsigned char *additional, size_t add_len )
+{
+ unsigned char add_input[MBEDTLS_CTR_DRBG_SEEDLEN];
+
+ if( add_len > 0 )
+ {
+ /* MAX_INPUT would be more logical here, but we have to match
+ * block_cipher_df()'s limits since we can't propagate errors */
+ if( add_len > MBEDTLS_CTR_DRBG_MAX_SEED_INPUT )
+ add_len = MBEDTLS_CTR_DRBG_MAX_SEED_INPUT;
+
+ block_cipher_df( add_input, additional, add_len );
+ ctr_drbg_update_internal( ctx, add_input );
+ }
+}
+
+int mbedtls_ctr_drbg_reseed( mbedtls_ctr_drbg_context *ctx,
+ const unsigned char *additional, size_t len )
+{
+ unsigned char seed[MBEDTLS_CTR_DRBG_MAX_SEED_INPUT];
+ size_t seedlen = 0;
+
+ if( ctx->entropy_len + len > MBEDTLS_CTR_DRBG_MAX_SEED_INPUT )
+ return( MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG );
+
+ memset( seed, 0, MBEDTLS_CTR_DRBG_MAX_SEED_INPUT );
+
+ /*
+ * Gather entropy_len bytes of entropy to seed state
+ */
+ if( 0 != ctx->f_entropy( ctx->p_entropy, seed,
+ ctx->entropy_len ) )
+ {
+ return( MBEDTLS_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED );
+ }
+
+ seedlen += ctx->entropy_len;
+
+ /*
+ * Add additional data
+ */
+ if( additional && len )
+ {
+ memcpy( seed + seedlen, additional, len );
+ seedlen += len;
+ }
+
+ /*
+ * Reduce to 384 bits
+ */
+ block_cipher_df( seed, seed, seedlen );
+
+ /*
+ * Update state
+ */
+ ctr_drbg_update_internal( ctx, seed );
+ ctx->reseed_counter = 1;
+
+ return( 0 );
+}
+
+int mbedtls_ctr_drbg_random_with_add( void *p_rng,
+ unsigned char *output, size_t output_len,
+ const unsigned char *additional, size_t add_len )
+{
+ int ret = 0;
+ mbedtls_ctr_drbg_context *ctx = (mbedtls_ctr_drbg_context *) p_rng;
+ unsigned char add_input[MBEDTLS_CTR_DRBG_SEEDLEN];
+ unsigned char *p = output;
+ unsigned char tmp[MBEDTLS_CTR_DRBG_BLOCKSIZE];
+ int i;
+ size_t use_len;
+
+ if( output_len > MBEDTLS_CTR_DRBG_MAX_REQUEST )
+ return( MBEDTLS_ERR_CTR_DRBG_REQUEST_TOO_BIG );
+
+ if( add_len > MBEDTLS_CTR_DRBG_MAX_INPUT )
+ return( MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG );
+
+ memset( add_input, 0, MBEDTLS_CTR_DRBG_SEEDLEN );
+
+ if( ctx->reseed_counter > ctx->reseed_interval ||
+ ctx->prediction_resistance )
+ {
+ if( ( ret = mbedtls_ctr_drbg_reseed( ctx, additional, add_len ) ) != 0 )
+ return( ret );
+
+ add_len = 0;
+ }
+
+ if( add_len > 0 )
+ {
+ block_cipher_df( add_input, additional, add_len );
+ ctr_drbg_update_internal( ctx, add_input );
+ }
+
+ while( output_len > 0 )
+ {
+ /*
+ * Increase counter
+ */
+ for( i = MBEDTLS_CTR_DRBG_BLOCKSIZE; i > 0; i-- )
+ if( ++ctx->counter[i - 1] != 0 )
+ break;
+
+ /*
+ * Crypt counter block
+ */
+ mbedtls_aes_crypt_ecb( &ctx->aes_ctx, MBEDTLS_AES_ENCRYPT, ctx->counter, tmp );
+
+ use_len = ( output_len > MBEDTLS_CTR_DRBG_BLOCKSIZE ) ? MBEDTLS_CTR_DRBG_BLOCKSIZE :
+ output_len;
+ /*
+ * Copy random block to destination
+ */
+ memcpy( p, tmp, use_len );
+ p += use_len;
+ output_len -= use_len;
+ }
+
+ ctr_drbg_update_internal( ctx, add_input );
+
+ ctx->reseed_counter++;
+
+ return( 0 );
+}
+
+int mbedtls_ctr_drbg_random( void *p_rng, unsigned char *output, size_t output_len )
+{
+ int ret;
+ mbedtls_ctr_drbg_context *ctx = (mbedtls_ctr_drbg_context *) p_rng;
+
+#if defined(MBEDTLS_THREADING_C)
+ if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
+ return( ret );
+#endif
+
+ ret = mbedtls_ctr_drbg_random_with_add( ctx, output, output_len, NULL, 0 );
+
+#if defined(MBEDTLS_THREADING_C)
+ if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
+ return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
+#endif
+
+ return( ret );
+}
+
+#if defined(MBEDTLS_FS_IO)
+int mbedtls_ctr_drbg_write_seed_file( mbedtls_ctr_drbg_context *ctx, const char *path )
+{
+ int ret = MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR;
+ FILE *f;
+ unsigned char buf[ MBEDTLS_CTR_DRBG_MAX_INPUT ];
+
+ if( ( f = fopen( path, "wb" ) ) == NULL )
+ return( MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR );
+
+ if( ( ret = mbedtls_ctr_drbg_random( ctx, buf, MBEDTLS_CTR_DRBG_MAX_INPUT ) ) != 0 )
+ goto exit;
+
+ if( fwrite( buf, 1, MBEDTLS_CTR_DRBG_MAX_INPUT, f ) != MBEDTLS_CTR_DRBG_MAX_INPUT )
+ {
+ ret = MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR;
+ goto exit;
+ }
+
+ ret = 0;
+
+exit:
+ fclose( f );
+ return( ret );
+}
+
+int mbedtls_ctr_drbg_update_seed_file( mbedtls_ctr_drbg_context *ctx, const char *path )
+{
+ FILE *f;
+ size_t n;
+ unsigned char buf[ MBEDTLS_CTR_DRBG_MAX_INPUT ];
+
+ if( ( f = fopen( path, "rb" ) ) == NULL )
+ return( MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR );
+
+ fseek( f, 0, SEEK_END );
+ n = (size_t) ftell( f );
+ fseek( f, 0, SEEK_SET );
+
+ if( n > MBEDTLS_CTR_DRBG_MAX_INPUT )
+ {
+ fclose( f );
+ return( MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG );
+ }
+
+ if( fread( buf, 1, n, f ) != n )
+ {
+ fclose( f );
+ return( MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR );
+ }
+
+ fclose( f );
+
+ mbedtls_ctr_drbg_update( ctx, buf, n );
+
+ return( mbedtls_ctr_drbg_write_seed_file( ctx, path ) );
+}
+#endif /* MBEDTLS_FS_IO */
+
+#if defined(MBEDTLS_SELF_TEST)
+
+static const unsigned char entropy_source_pr[96] =
+ { 0xc1, 0x80, 0x81, 0xa6, 0x5d, 0x44, 0x02, 0x16,
+ 0x19, 0xb3, 0xf1, 0x80, 0xb1, 0xc9, 0x20, 0x02,
+ 0x6a, 0x54, 0x6f, 0x0c, 0x70, 0x81, 0x49, 0x8b,
+ 0x6e, 0xa6, 0x62, 0x52, 0x6d, 0x51, 0xb1, 0xcb,
+ 0x58, 0x3b, 0xfa, 0xd5, 0x37, 0x5f, 0xfb, 0xc9,
+ 0xff, 0x46, 0xd2, 0x19, 0xc7, 0x22, 0x3e, 0x95,
+ 0x45, 0x9d, 0x82, 0xe1, 0xe7, 0x22, 0x9f, 0x63,
+ 0x31, 0x69, 0xd2, 0x6b, 0x57, 0x47, 0x4f, 0xa3,
+ 0x37, 0xc9, 0x98, 0x1c, 0x0b, 0xfb, 0x91, 0x31,
+ 0x4d, 0x55, 0xb9, 0xe9, 0x1c, 0x5a, 0x5e, 0xe4,
+ 0x93, 0x92, 0xcf, 0xc5, 0x23, 0x12, 0xd5, 0x56,
+ 0x2c, 0x4a, 0x6e, 0xff, 0xdc, 0x10, 0xd0, 0x68 };
+
+static const unsigned char entropy_source_nopr[64] =
+ { 0x5a, 0x19, 0x4d, 0x5e, 0x2b, 0x31, 0x58, 0x14,
+ 0x54, 0xde, 0xf6, 0x75, 0xfb, 0x79, 0x58, 0xfe,
+ 0xc7, 0xdb, 0x87, 0x3e, 0x56, 0x89, 0xfc, 0x9d,
+ 0x03, 0x21, 0x7c, 0x68, 0xd8, 0x03, 0x38, 0x20,
+ 0xf9, 0xe6, 0x5e, 0x04, 0xd8, 0x56, 0xf3, 0xa9,
+ 0xc4, 0x4a, 0x4c, 0xbd, 0xc1, 0xd0, 0x08, 0x46,
+ 0xf5, 0x98, 0x3d, 0x77, 0x1c, 0x1b, 0x13, 0x7e,
+ 0x4e, 0x0f, 0x9d, 0x8e, 0xf4, 0x09, 0xf9, 0x2e };
+
+static const unsigned char nonce_pers_pr[16] =
+ { 0xd2, 0x54, 0xfc, 0xff, 0x02, 0x1e, 0x69, 0xd2,
+ 0x29, 0xc9, 0xcf, 0xad, 0x85, 0xfa, 0x48, 0x6c };
+
+static const unsigned char nonce_pers_nopr[16] =
+ { 0x1b, 0x54, 0xb8, 0xff, 0x06, 0x42, 0xbf, 0xf5,
+ 0x21, 0xf1, 0x5c, 0x1c, 0x0b, 0x66, 0x5f, 0x3f };
+
+static const unsigned char result_pr[16] =
+ { 0x34, 0x01, 0x16, 0x56, 0xb4, 0x29, 0x00, 0x8f,
+ 0x35, 0x63, 0xec, 0xb5, 0xf2, 0x59, 0x07, 0x23 };
+
+static const unsigned char result_nopr[16] =
+ { 0xa0, 0x54, 0x30, 0x3d, 0x8a, 0x7e, 0xa9, 0x88,
+ 0x9d, 0x90, 0x3e, 0x07, 0x7c, 0x6f, 0x21, 0x8f };
+
+static size_t test_offset;
+static int ctr_drbg_self_test_entropy( void *data, unsigned char *buf,
+ size_t len )
+{
+ const unsigned char *p = data;
+ memcpy( buf, p + test_offset, len );
+ test_offset += len;
+ return( 0 );
+}
+
+#define CHK( c ) if( (c) != 0 ) \
+ { \
+ if( verbose != 0 ) \
+ mbedtls_printf( "failed\n" ); \
+ return( 1 ); \
+ }
+
+/*
+ * Checkup routine
+ */
+int mbedtls_ctr_drbg_self_test( int verbose )
+{
+ mbedtls_ctr_drbg_context ctx;
+ unsigned char buf[16];
+
+ mbedtls_ctr_drbg_init( &ctx );
+
+ /*
+ * Based on a NIST CTR_DRBG test vector (PR = True)
+ */
+ if( verbose != 0 )
+ mbedtls_printf( " CTR_DRBG (PR = TRUE) : " );
+
+ test_offset = 0;
+ CHK( mbedtls_ctr_drbg_seed_entropy_len( &ctx, ctr_drbg_self_test_entropy,
+ (void *) entropy_source_pr, nonce_pers_pr, 16, 32 ) );
+ mbedtls_ctr_drbg_set_prediction_resistance( &ctx, MBEDTLS_CTR_DRBG_PR_ON );
+ CHK( mbedtls_ctr_drbg_random( &ctx, buf, MBEDTLS_CTR_DRBG_BLOCKSIZE ) );
+ CHK( mbedtls_ctr_drbg_random( &ctx, buf, MBEDTLS_CTR_DRBG_BLOCKSIZE ) );
+ CHK( memcmp( buf, result_pr, MBEDTLS_CTR_DRBG_BLOCKSIZE ) );
+
+ mbedtls_ctr_drbg_free( &ctx );
+
+ if( verbose != 0 )
+ mbedtls_printf( "passed\n" );
+
+ /*
+ * Based on a NIST CTR_DRBG test vector (PR = FALSE)
+ */
+ if( verbose != 0 )
+ mbedtls_printf( " CTR_DRBG (PR = FALSE): " );
+
+ mbedtls_ctr_drbg_init( &ctx );
+
+ test_offset = 0;
+ CHK( mbedtls_ctr_drbg_seed_entropy_len( &ctx, ctr_drbg_self_test_entropy,
+ (void *) entropy_source_nopr, nonce_pers_nopr, 16, 32 ) );
+ CHK( mbedtls_ctr_drbg_random( &ctx, buf, 16 ) );
+ CHK( mbedtls_ctr_drbg_reseed( &ctx, NULL, 0 ) );
+ CHK( mbedtls_ctr_drbg_random( &ctx, buf, 16 ) );
+ CHK( memcmp( buf, result_nopr, 16 ) );
+
+ mbedtls_ctr_drbg_free( &ctx );
+
+ if( verbose != 0 )
+ mbedtls_printf( "passed\n" );
+
+ if( verbose != 0 )
+ mbedtls_printf( "\n" );
+
+ return( 0 );
+}
+#endif /* MBEDTLS_SELF_TEST */
+
+#endif /* MBEDTLS_CTR_DRBG_C */