/*
* Non-public function wrapped by ctr_crbg_init(). Necessary to allow NIST
* tests to succeed (which require known length fixed entropy)
*/
int ctr_drbg_init_entropy_len(
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[CTR_DRBG_KEYSIZE];
memset( ctx, 0, sizeof(ctr_drbg_context) );
memset( key, 0, CTR_DRBG_KEYSIZE );
ctx->f_entropy = f_entropy;
ctx->p_entropy = p_entropy;
ctx->entropy_len = entropy_len;
ctx->reseed_interval = CTR_DRBG_RESEED_INTERVAL;
/*
* Initialize with an empty key
*/
aes_setkey_enc( &ctx->aes_ctx, key, CTR_DRBG_KEYBITS );
if( ( ret = ctr_drbg_reseed( ctx, custom, len ) ) != 0 )
return( ret );
return( 0 );
}
int rand_ctx_reseed()
{
ctr_drbg_context *cd_ctx = rand_ctx_get();
entropy_context *ec = cd_ctx->p_entropy;
ASSERT(NULL != ec);
if (!entropy_gather_blocking(ec))
return 0;
if (0 != ctr_drbg_reseed(cd_ctx, NULL, 0))
return 0;
return 1;
}
/* Push new entropy into the CTR_DRBG instance in ctx, combining
* it with the entropy already there. On success, 0 is returned. If
* the callback returns a non-zero value, that value is returned.
* Other errors return -1.
*/
static int
fips_drbg_reseed(struct fips_drbg_ctx_s *ctx)
{
uint8_t entropy_pool[Q_HW_DRBG_BLOCK_BYTES];
int rv;
enum ctr_drbg_status_t init_rv;
if (ctx == NULL)
return FIPS140_PRNG_ERR;
if (!ctx->fips_drbg_started) {
rv = (*ctx->get_entropy_callback)(ctx->get_entropy_callback_ctx,
ctx->prev_hw_drbg_block
);
if (rv != 0)
return FIPS140_PRNG_ERR;
ctx->fips_drbg_started = 1;
}
rv = (*ctx->get_entropy_callback)(ctx->get_entropy_callback_ctx,
entropy_pool
);
if (rv != 0) {
memset(entropy_pool, 0, Q_HW_DRBG_BLOCK_BYTES);
return FIPS140_PRNG_ERR;
}
if (!memcmp(entropy_pool,
ctx->prev_hw_drbg_block,
Q_HW_DRBG_BLOCK_BYTES)) {
memset(entropy_pool, 0, Q_HW_DRBG_BLOCK_BYTES);
return FIPS140_PRNG_ERR;
} else
memcpy(ctx->prev_hw_drbg_block,
entropy_pool,
Q_HW_DRBG_BLOCK_BYTES);
init_rv = ctr_drbg_reseed(&ctx->ctr_drbg_ctx,
entropy_pool,
8*MSM_ENTROPY_BUFFER_SIZE);
/* Zeroize the buffer for security. */
memset(entropy_pool, 0, Q_HW_DRBG_BLOCK_BYTES);
return (init_rv == CTR_DRBG_SUCCESS ?
FIPS140_PRNG_OK :
FIPS140_PRNG_ERR);
}
/*
* Checkup routine
*/
int ctr_drbg_self_test( int verbose )
{
ctr_drbg_context ctx;
unsigned char buf[16];
/*
* Based on a NIST CTR_DRBG test vector (PR = True)
*/
if( verbose != 0 )
polarssl_printf( " CTR_DRBG (PR = TRUE) : " );
test_offset = 0;
CHK( ctr_drbg_init_entropy_len( &ctx, ctr_drbg_self_test_entropy,
entropy_source_pr, nonce_pers_pr, 16, 32 ) );
ctr_drbg_set_prediction_resistance( &ctx, CTR_DRBG_PR_ON );
CHK( ctr_drbg_random( &ctx, buf, CTR_DRBG_BLOCKSIZE ) );
CHK( ctr_drbg_random( &ctx, buf, CTR_DRBG_BLOCKSIZE ) );
CHK( memcmp( buf, result_pr, CTR_DRBG_BLOCKSIZE ) );
if( verbose != 0 )
polarssl_printf( "passed\n" );
/*
* Based on a NIST CTR_DRBG test vector (PR = FALSE)
*/
if( verbose != 0 )
polarssl_printf( " CTR_DRBG (PR = FALSE): " );
test_offset = 0;
CHK( ctr_drbg_init_entropy_len( &ctx, ctr_drbg_self_test_entropy,
entropy_source_nopr, nonce_pers_nopr, 16, 32 ) );
CHK( ctr_drbg_random( &ctx, buf, 16 ) );
CHK( ctr_drbg_reseed( &ctx, NULL, 0 ) );
CHK( ctr_drbg_random( &ctx, buf, 16 ) );
CHK( memcmp( buf, result_nopr, 16 ) );
if( verbose != 0 )
polarssl_printf( "passed\n" );
if( verbose != 0 )
polarssl_printf( "\n" );
return( 0 );
}
int 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;
ctr_drbg_context *ctx = (ctr_drbg_context *) p_rng;
unsigned char add_input[CTR_DRBG_SEEDLEN];
unsigned char *p = output;
unsigned char tmp[CTR_DRBG_BLOCKSIZE];
int i;
size_t use_len;
if( output_len > CTR_DRBG_MAX_REQUEST )
return( POLARSSL_ERR_CTR_DRBG_REQUEST_TOO_BIG );
if( add_len > CTR_DRBG_MAX_INPUT )
return( POLARSSL_ERR_CTR_DRBG_INPUT_TOO_BIG );
memset( add_input, 0, CTR_DRBG_SEEDLEN );
if( ctx->reseed_counter > ctx->reseed_interval ||
ctx->prediction_resistance )
{
if( ( ret = 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 = CTR_DRBG_BLOCKSIZE; i > 0; i-- )
if( ++ctx->counter[i - 1] != 0 )
break;
/*
* Crypt counter block
*/
aes_crypt_ecb( &ctx->aes_ctx, AES_ENCRYPT, ctx->counter, tmp );
use_len = (output_len > CTR_DRBG_BLOCKSIZE ) ? 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 main( int argc, char *argv[] )
{
int ret, len, cnt = 0, pid;
int listen_fd;
int client_fd;
unsigned char buf[1024];
const char *pers = "ssl_fork_server";
entropy_context entropy;
ctr_drbg_context ctr_drbg;
ssl_context ssl;
x509_cert srvcert;
rsa_context rsa;
((void) argc);
((void) argv);
signal( SIGCHLD, SIG_IGN );
/*
* 0. Initial seeding of the RNG
*/
printf( "\n . Initial seeding of the random generator..." );
fflush( stdout );
entropy_init( &entropy );
if( ( ret = ctr_drbg_init( &ctr_drbg, entropy_func, &entropy,
(const unsigned char *) pers,
strlen( pers ) ) ) != 0 )
{
printf( " failed\n ! ctr_drbg_init returned %d\n", ret );
goto exit;
}
printf( " ok\n" );
/*
* 1. Load the certificates and private RSA key
*/
printf( " . Loading the server cert. and key..." );
fflush( stdout );
memset( &srvcert, 0, sizeof( x509_cert ) );
/*
* This demonstration program uses embedded test certificates.
* Instead, you may want to use x509parse_crtfile() to read the
* server and CA certificates, as well as x509parse_keyfile().
*/
ret = x509parse_crt( &srvcert, (const unsigned char *) test_srv_crt,
strlen( test_srv_crt ) );
if( ret != 0 )
{
printf( " failed\n ! x509parse_crt returned %d\n\n", ret );
goto exit;
}
ret = x509parse_crt( &srvcert, (const unsigned char *) test_ca_crt,
strlen( test_ca_crt ) );
if( ret != 0 )
{
printf( " failed\n ! x509parse_crt returned %d\n\n", ret );
goto exit;
}
rsa_init( &rsa, RSA_PKCS_V15, 0 );
ret = x509parse_key( &rsa, (const unsigned char *) test_srv_key,
strlen( test_srv_key ), NULL, 0 );
if( ret != 0 )
{
printf( " failed\n ! x509parse_key returned %d\n\n", ret );
goto exit;
}
printf( " ok\n" );
/*
* 2. Setup the listening TCP socket
*/
printf( " . Bind on https://localhost:4433/ ..." );
fflush( stdout );
if( ( ret = net_bind( &listen_fd, NULL, 4433 ) ) != 0 )
{
printf( " failed\n ! net_bind returned %d\n\n", ret );
goto exit;
}
printf( " ok\n" );
while( 1 )
{
/*
* 3. Wait until a client connects
*/
client_fd = -1;
memset( &ssl, 0, sizeof( ssl ) );
printf( " . Waiting for a remote connection ..." );
fflush( stdout );
if( ( ret = net_accept( listen_fd, &client_fd, NULL ) ) != 0 )
{
printf( " failed\n ! net_accept returned %d\n\n", ret );
goto exit;
}
printf( " ok\n" );
/*
* 3.5. Forking server thread
*/
pid = fork();
printf( " . Forking to handle connection ..." );
fflush( stdout );
if( pid < 0 )
{
printf(" failed\n ! fork returned %d\n\n", pid );
goto exit;
}
printf( " ok\n" );
if( pid != 0 )
{
if( ( ret = ctr_drbg_reseed( &ctr_drbg,
(const unsigned char *) "parent",
6 ) ) != 0 )
{
printf( " failed\n ! ctr_drbg_reseed returned %d\n", ret );
goto exit;
}
close( client_fd );
continue;
}
close( listen_fd );
/*
* 4. Setup stuff
*/
printf( " . Setting up the SSL data...." );
fflush( stdout );
if( ( ret = ctr_drbg_reseed( &ctr_drbg,
(const unsigned char *) "child",
5 ) ) != 0 )
{
printf( " failed\n ! ctr_drbg_reseed returned %d\n", ret );
goto exit;
}
if( ( ret = ssl_init( &ssl ) ) != 0 )
{
printf( " failed\n ! ssl_init returned %d\n\n", ret );
goto exit;
}
printf( " ok\n" );
ssl_set_endpoint( &ssl, SSL_IS_SERVER );
ssl_set_authmode( &ssl, SSL_VERIFY_NONE );
ssl_set_rng( &ssl, ctr_drbg_random, &ctr_drbg );
ssl_set_dbg( &ssl, my_debug, stdout );
ssl_set_bio( &ssl, net_recv, &client_fd,
net_send, &client_fd );
ssl_set_ca_chain( &ssl, srvcert.next, NULL, NULL );
ssl_set_own_cert( &ssl, &srvcert, &rsa );
/*
* 5. Handshake
*/
printf( " . Performing the SSL/TLS handshake..." );
fflush( stdout );
while( ( ret = ssl_handshake( &ssl ) ) != 0 )
{
if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
{
printf( " failed\n ! ssl_handshake returned %d\n\n", ret );
goto exit;
}
}
printf( " ok\n" );
/*
* 6. Read the HTTP Request
*/
printf( " < Read from client:" );
fflush( stdout );
do
{
len = sizeof( buf ) - 1;
memset( buf, 0, sizeof( buf ) );
ret = ssl_read( &ssl, buf, len );
if( ret == POLARSSL_ERR_NET_WANT_READ || ret == POLARSSL_ERR_NET_WANT_WRITE )
continue;
if( ret <= 0 )
{
switch( ret )
{
case POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY:
printf( " connection was closed gracefully\n" );
break;
case POLARSSL_ERR_NET_CONN_RESET:
printf( " connection was reset by peer\n" );
break;
default:
printf( " ssl_read returned %d\n", ret );
break;
}
break;
}
len = ret;
printf( " %d bytes read\n\n%s", len, (char *) buf );
}
while( 0 );
/*
* 7. Write the 200 Response
*/
printf( " > Write to client:" );
fflush( stdout );
len = sprintf( (char *) buf, HTTP_RESPONSE,
ssl_get_ciphersuite( &ssl ) );
while( cnt < 100 )
{
while( ( ret = ssl_write( &ssl, buf, len ) ) <= 0 )
{
if( ret == POLARSSL_ERR_NET_CONN_RESET )
{
printf( " failed\n ! peer closed the connection\n\n" );
goto exit;
}
if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
{
printf( " failed\n ! ssl_write returned %d\n\n", ret );
goto exit;
}
}
len = ret;
printf( " %d bytes written\n\n%s\n", len, (char *) buf );
m_sleep( 1000 );
}
ssl_close_notify( &ssl );
goto exit;
}
exit:
net_close( client_fd );
x509_free( &srvcert );
rsa_free( &rsa );
ssl_free( &ssl );
#if defined(_WIN32)
printf( " Press Enter to exit this program.\n" );
fflush( stdout ); getchar();
#endif
return( ret );
}
