Commit 66ff70dd authored by Paul Bakker's avatar Paul Bakker
Browse files

Support for seed file writing and reading in Entropy

parent 766a5d02
......@@ -11,6 +11,7 @@ Features
* Testing script ssl-opt.sh added for testing 'live' ssl option
interoperability against OpenSSL and PolarSSL
* Support for reading EC keys that use SpecifiedECDomain in some cases.
* Entropy module now supports seed writing and reading
Changes
* Deprecated the Memory layer
......
......@@ -52,6 +52,7 @@
#define POLARSSL_ERR_ENTROPY_SOURCE_FAILED -0x003C /**< Critical entropy source failure. */
#define POLARSSL_ERR_ENTROPY_MAX_SOURCES -0x003E /**< No more sources can be added. */
#define POLARSSL_ERR_ENTROPY_NO_SOURCES_DEFINED -0x0040 /**< No sources have been added to poll. */
#define POLARSSL_ERR_ENTROPY_FILE_IO_ERROR -0x0058 /**< Read/write error in file. */
#if !defined(POLARSSL_CONFIG_OPTIONS)
#define ENTROPY_MAX_SOURCES 20 /**< Maximum number of sources supported */
......@@ -64,6 +65,7 @@
#define ENTROPY_BLOCK_SIZE 32 /**< Block size of entropy accumulator (SHA-256) */
#endif
#define ENTROPY_MAX_SEED_SIZE 1024 /**< Maximum size of seed we read from seed file */
#define ENTROPY_SOURCE_MANUAL ENTROPY_MAX_SOURCES
#ifdef __cplusplus
......@@ -182,6 +184,34 @@ int entropy_func( void *data, unsigned char *output, size_t len );
int entropy_update_manual( entropy_context *ctx,
const unsigned char *data, size_t len );
#if defined(POLARSSL_FS_IO)
/**
* \brief Write a seed file
*
* \param ctx Entropy context
* \param path Name of the file
*
* \return 0 if successful,
* POLARSSL_ERR_ENTROPY_FILE_IO_ERROR on file error, or
* POLARSSL_ERR_ENTROPY_SOURCE_FAILED
*/
int entropy_write_seed_file( entropy_context *ctx, const char *path );
/**
* \brief Read and update a seed file. Seed is added to this
* instance. No more than ENTROPY_MAX_SEED_SIZE bytes are
* read from the seed file. The rest is ignored.
*
* \param ctx Entropy context
* \param path Name of the file
*
* \return 0 if successful,
* POLARSSL_ERR_ENTROPY_FILE_IO_ERROR on file error,
* POLARSSL_ERR_ENTROPY_SOURCE_FAILED
*/
int entropy_update_seed_file( entropy_context *ctx, const char *path );
#endif
#ifdef __cplusplus
}
#endif
......
......@@ -66,6 +66,7 @@
* CTR_DBRG 4 0x0034-0x003A
* ENTROPY 3 0x003C-0x0040
* NET 11 0x0042-0x0056
* ENTROPY 1 0x0058-0x0058
* ASN1 7 0x0060-0x006C
* MD2 1 0x0070-0x0070
* MD4 1 0x0072-0x0072
......
......@@ -30,6 +30,10 @@
#include "polarssl/entropy.h"
#include "polarssl/entropy_poll.h"
#if defined(POLARSSL_FS_IO)
#include <stdio.h>
#endif
#if defined(POLARSSL_HAVEGE_C)
#include "polarssl/havege.h"
#endif
......@@ -308,4 +312,60 @@ exit:
return( ret );
}
#if defined(POLARSSL_FS_IO)
int entropy_write_seed_file( entropy_context *ctx, const char *path )
{
int ret = POLARSSL_ERR_ENTROPY_FILE_IO_ERROR;
FILE *f;
unsigned char buf[ENTROPY_BLOCK_SIZE];
if( ( f = fopen( path, "wb" ) ) == NULL )
return( POLARSSL_ERR_ENTROPY_FILE_IO_ERROR );
if( ( ret = entropy_func( ctx, buf, ENTROPY_BLOCK_SIZE ) ) != 0 )
goto exit;
if( fwrite( buf, 1, ENTROPY_BLOCK_SIZE, f ) != ENTROPY_BLOCK_SIZE )
{
ret = POLARSSL_ERR_ENTROPY_FILE_IO_ERROR;
goto exit;
}
ret = 0;
exit:
fclose( f );
return( ret );
}
int entropy_update_seed_file( entropy_context *ctx, const char *path )
{
FILE *f;
size_t n;
unsigned char buf[ ENTROPY_MAX_SEED_SIZE ];
if( ( f = fopen( path, "rb" ) ) == NULL )
return( POLARSSL_ERR_ENTROPY_FILE_IO_ERROR );
fseek( f, 0, SEEK_END );
n = (size_t) ftell( f );
fseek( f, 0, SEEK_SET );
if( n > ENTROPY_MAX_SEED_SIZE )
n = ENTROPY_MAX_SEED_SIZE;
if( fread( buf, 1, n, f ) != n )
{
fclose( f );
return( POLARSSL_ERR_ENTROPY_FILE_IO_ERROR );
}
fclose( f );
entropy_update_manual( ctx, buf, n );
return( entropy_write_seed_file( ctx, path ) );
}
#endif /* POLARSSL_FS_IO */
#endif
......@@ -590,6 +590,8 @@ void polarssl_strerror( int ret, char *buf, size_t buflen )
snprintf( buf, buflen, "ENTROPY - No more sources can be added" );
if( use_ret == -(POLARSSL_ERR_ENTROPY_NO_SOURCES_DEFINED) )
snprintf( buf, buflen, "ENTROPY - No sources have been added to poll" );
if( use_ret == -(POLARSSL_ERR_ENTROPY_FILE_IO_ERROR) )
snprintf( buf, buflen, "ENTROPY - Read/write error in file" );
#endif /* POLARSSL_ENTROPY_C */
#if defined(POLARSSL_GCM_C)
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment