Merge branch 'maximum-fragment-length' into development

This commit is contained in:
Paul Bakker 2013-07-19 14:00:29 +02:00
commit a7eaba5ef9
6 changed files with 320 additions and 55 deletions

View File

@ -117,6 +117,15 @@
#define SSL_MINOR_VERSION_2 2 /*!< TLS v1.1 */
#define SSL_MINOR_VERSION_3 3 /*!< TLS v1.2 */
/* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c
* NONE must be zero so that memset()ing structure to zero works */
#define SSL_MAX_FRAG_LEN_NONE 0 /*!< don't use this extension */
#define SSL_MAX_FRAG_LEN_512 1 /*!< MaxFragmentLength 2^9 */
#define SSL_MAX_FRAG_LEN_1024 2 /*!< MaxFragmentLength 2^10 */
#define SSL_MAX_FRAG_LEN_2048 3 /*!< MaxFragmentLength 2^11 */
#define SSL_MAX_FRAG_LEN_4096 4 /*!< MaxFragmentLength 2^12 */
#define SSL_MAX_FRAG_LEN_INVALID 5 /*!< first invalid value */
#define SSL_IS_CLIENT 0
#define SSL_IS_SERVER 1
#define SSL_COMPRESS_NULL 0
@ -240,6 +249,8 @@
#define TLS_EXT_SERVERNAME 0
#define TLS_EXT_SERVERNAME_HOSTNAME 0
#define TLS_EXT_MAX_FRAGMENT_LENGTH 1
#define TLS_EXT_SUPPORTED_ELLIPTIC_CURVES 10
#define TLS_EXT_SUPPORTED_POINT_FORMATS 11
@ -320,6 +331,8 @@ struct _ssl_session
#if defined(POLARSSL_X509_PARSE_C)
x509_cert *peer_cert; /*!< peer X.509 cert chain */
#endif /* POLARSSL_X509_PARSE_C */
unsigned char mfl_code; /*!< MaxFragmentLength negotiated by peer */
};
/*
@ -498,6 +511,8 @@ struct _ssl_context
size_t out_msglen; /*!< record header: message length */
size_t out_left; /*!< amount of data not yet written */
unsigned char mfl_code; /*!< MaxFragmentLength chosen by us */
/*
* PKI layer
*/
@ -944,6 +959,23 @@ void ssl_set_max_version( ssl_context *ssl, int major, int minor );
*/
void ssl_set_min_version( ssl_context *ssl, int major, int minor );
/**
* \brief Set the maximum fragment length to emit and/or negotiate
* (Default: SSL_MAX_CONTENT_LEN, usually 2^14 bytes)
* (Server: set maximum fragment length to emit,
* usually negotiated by the client during handshake
* (Client: set maximum fragment length to emit *and*
* negotiate with the server during handshake)
*
* \param ssl SSL context
* \param mfl Code for maximum fragment length (allowed values:
* SSL_MAX_FRAG_LEN_512, SSL_MAX_FRAG_LEN_1024,
* SSL_MAX_FRAG_LEN_2048, SSL_MAX_FRAG_LEN_4096)
*
* \return O if successful or POLARSSL_ERR_SSL_BAD_INPUT_DATA
*/
int ssl_set_max_frag_len( ssl_context *ssl, unsigned char mfl_code );
/**
* \brief Enable / Disable renegotiation support for connection when
* initiated by peer

View File

@ -269,6 +269,30 @@ static void ssl_write_supported_point_formats_ext( ssl_context *ssl,
}
#endif
static void ssl_write_max_fragment_length_ext( ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
unsigned char *p = buf;
if( ssl->mfl_code == SSL_MAX_FRAG_LEN_NONE ) {
*olen = 0;
return;
}
SSL_DEBUG_MSG( 3, ( "client hello, adding max_fragment_length extension" ) );
*p++ = (unsigned char)( ( TLS_EXT_MAX_FRAGMENT_LENGTH >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( TLS_EXT_MAX_FRAGMENT_LENGTH ) & 0xFF );
*p++ = 0x00;
*p++ = 1;
*p++ = ssl->mfl_code;
*olen = 5;
}
static int ssl_write_client_hello( ssl_context *ssl )
{
int ret;
@ -436,6 +460,9 @@ static int ssl_write_client_hello( ssl_context *ssl )
ext_len += olen;
#endif
ssl_write_max_fragment_length_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
SSL_DEBUG_MSG( 3, ( "client hello, total extension length: %d",
ext_len ) );
@ -461,7 +488,7 @@ static int ssl_write_client_hello( ssl_context *ssl )
}
static int ssl_parse_renegotiation_info( ssl_context *ssl,
unsigned char *buf,
const unsigned char *buf,
size_t len )
{
int ret;
@ -499,6 +526,23 @@ static int ssl_parse_renegotiation_info( ssl_context *ssl,
return( 0 );
}
static int ssl_parse_max_fragment_length_ext( ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
/*
* server should use the extension only if we did,
* and if so the server's value should match ours (and len is always 1)
*/
if( ssl->mfl_code == SSL_MAX_FRAG_LEN_NONE ||
len != 1 ||
buf[0] != ssl->mfl_code )
{
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
return( 0 );
}
static int ssl_parse_server_hello( ssl_context *ssl )
{
@ -690,6 +734,8 @@ static int ssl_parse_server_hello( ssl_context *ssl )
ext = buf + 44 + n;
SSL_DEBUG_MSG( 2, ( "server hello, total extension length: %d", ext_len ) );
while( ext_len )
{
unsigned int ext_id = ( ( ext[0] << 8 )
@ -714,6 +760,17 @@ static int ssl_parse_server_hello( ssl_context *ssl )
break;
case TLS_EXT_MAX_FRAGMENT_LENGTH:
SSL_DEBUG_MSG( 3, ( "found max_fragment_length extension" ) );
if( ( ret = ssl_parse_max_fragment_length_ext( ssl,
ext + 4, ext_size ) ) != 0 )
{
return( ret );
}
break;
default:
SSL_DEBUG_MSG( 3, ( "unknown extension found: %d (ignoring)",
ext_id ) );

View File

@ -291,6 +291,21 @@ static int ssl_parse_supported_point_formats( ssl_context *ssl,
}
#endif /* POLARSSL_ECP_C */
static int ssl_parse_max_fragment_length_ext( ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
if( len != 1 || buf[0] >= SSL_MAX_FRAG_LEN_INVALID )
{
SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
ssl->session_negotiate->mfl_code = buf[0];
return( 0 );
}
#if defined(POLARSSL_SSL_SRV_SUPPORT_SSLV2_CLIENT_HELLO)
static int ssl_parse_client_hello_v2( ssl_context *ssl )
{
@ -825,6 +840,14 @@ static int ssl_parse_client_hello( ssl_context *ssl )
break;
#endif /* POLARSSL_ECP_C */
case TLS_EXT_MAX_FRAGMENT_LENGTH:
SSL_DEBUG_MSG( 3, ( "found max fragment length extension" ) );
ret = ssl_parse_max_fragment_length_ext( ssl, ext + 4, ext_size );
if( ret != 0 )
return( ret );
break;
default:
SSL_DEBUG_MSG( 3, ( "unknown extension found: %d (ignoring)",
ext_id ) );
@ -934,13 +957,67 @@ have_ciphersuite:
return( 0 );
}
static void ssl_write_renegotiation_ext( ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
unsigned char *p = buf;
if( ssl->secure_renegotiation != SSL_SECURE_RENEGOTIATION )
{
*olen = 0;
return;
}
SSL_DEBUG_MSG( 3, ( "server hello, secure renegotiation extension" ) );
*p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO ) & 0xFF );
*p++ = 0x00;
*p++ = ( ssl->verify_data_len * 2 + 1 ) & 0xFF;
*p++ = ssl->verify_data_len * 2 & 0xFF;
memcpy( p, ssl->peer_verify_data, ssl->verify_data_len );
p += ssl->verify_data_len;
memcpy( p, ssl->own_verify_data, ssl->verify_data_len );
p += ssl->verify_data_len;
*olen = 5 + ssl->verify_data_len * 2;
}
static void ssl_write_max_fragment_length_ext( ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
unsigned char *p = buf;
if( ssl->session_negotiate->mfl_code == SSL_MAX_FRAG_LEN_NONE )
{
*olen = 0;
return;
}
SSL_DEBUG_MSG( 3, ( "server hello, max_fragment_length extension" ) );
*p++ = (unsigned char)( ( TLS_EXT_MAX_FRAGMENT_LENGTH >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( TLS_EXT_MAX_FRAGMENT_LENGTH ) & 0xFF );
*p++ = 0x00;
*p++ = 1;
*p++ = ssl->session_negotiate->mfl_code;
*olen = 5;
}
static int ssl_write_server_hello( ssl_context *ssl )
{
#if defined(POLARSSL_HAVE_TIME)
time_t t;
#endif
int ret, n;
size_t ext_len = 0;
size_t olen, ext_len = 0;
unsigned char *buf, *p;
SSL_DEBUG_MSG( 2, ( "=> write server hello" ) );
@ -990,6 +1067,8 @@ static int ssl_write_server_hello( ssl_context *ssl )
* 39 . 38+n session id
* 39+n . 40+n chosen ciphersuite
* 41+n . 41+n chosen compression alg.
* 42+n . 43+n extensions length
* 44+n . 43+n+m extensions
*/
ssl->session_negotiate->length = n = 32;
*p++ = (unsigned char) ssl->session_negotiate->length;
@ -1040,34 +1119,20 @@ static int ssl_write_server_hello( ssl_context *ssl )
SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: %d",
ssl->session_negotiate->compression ) );
if( ssl->secure_renegotiation == SSL_SECURE_RENEGOTIATION )
{
SSL_DEBUG_MSG( 3, ( "server hello, prepping for secure renegotiation extension" ) );
ext_len += 5 + ssl->verify_data_len * 2;
/*
* First write extensions, then the total length
*/
ssl_write_renegotiation_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
SSL_DEBUG_MSG( 3, ( "server hello, total extension length: %d",
ext_len ) );
ssl_write_max_fragment_length_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
SSL_DEBUG_MSG( 3, ( "server hello, total extension length: %d", ext_len ) );
*p++ = (unsigned char)( ( ext_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ext_len ) & 0xFF );
/*
* Secure renegotiation
*/
SSL_DEBUG_MSG( 3, ( "client hello, secure renegotiation extension" ) );
*p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO ) & 0xFF );
*p++ = 0x00;
*p++ = ( ssl->verify_data_len * 2 + 1 ) & 0xFF;
*p++ = ssl->verify_data_len * 2 & 0xFF;
memcpy( p, ssl->peer_verify_data, ssl->verify_data_len );
p += ssl->verify_data_len;
memcpy( p, ssl->own_verify_data, ssl->verify_data_len );
p += ssl->verify_data_len;
}
p += ext_len;
ssl->out_msglen = p - buf;
ssl->out_msgtype = SSL_MSG_HANDSHAKE;

View File

@ -59,6 +59,23 @@
#define strcasecmp _stricmp
#endif
/*
* Convert max_fragment_length codes to length.
* RFC 6066 says:
* enum{
* 2^9(1), 2^10(2), 2^11(3), 2^12(4), (255)
* } MaxFragmentLength;
* and we add 0 -> extension unused
*/
static unsigned int mfl_code_to_length[SSL_MAX_FRAG_LEN_INVALID] =
{
SSL_MAX_CONTENT_LEN, /* SSL_MAX_FRAG_LEN_NONE */
512, /* SSL_MAX_FRAG_LEN_512 */
1024, /* SSL_MAX_FRAG_LEN_1024 */
2048, /* SSL_MAX_FRAG_LEN_2048 */
4096, /* SSL_MAX_FRAG_LEN_4096 */
};
#if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
int (*ssl_hw_record_init)(ssl_context *ssl,
const unsigned char *key_enc, const unsigned char *key_dec,
@ -3111,6 +3128,19 @@ void ssl_set_min_version( ssl_context *ssl, int major, int minor )
ssl->min_minor_ver = minor;
}
int ssl_set_max_frag_len( ssl_context *ssl, unsigned char mfl_code )
{
if( mfl_code >= sizeof( mfl_code_to_length ) ||
mfl_code_to_length[mfl_code] > SSL_MAX_CONTENT_LEN )
{
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
ssl->mfl_code = mfl_code;
return( 0 );
}
void ssl_set_renegotiation( ssl_context *ssl, int renegotiation )
{
ssl->disable_renegotiation = renegotiation;
@ -3372,6 +3402,7 @@ int ssl_write( ssl_context *ssl, const unsigned char *buf, size_t len )
{
int ret;
size_t n;
unsigned int max_len;
SSL_DEBUG_MSG( 2, ( "=> write" ) );
@ -3384,8 +3415,21 @@ int ssl_write( ssl_context *ssl, const unsigned char *buf, size_t len )
}
}
n = ( len < SSL_MAX_CONTENT_LEN )
? len : SSL_MAX_CONTENT_LEN;
/*
* Assume mfl_code is correct since it was checked when set
*/
max_len = mfl_code_to_length[ssl->mfl_code];
/*
* Check if a smaller max length was negociated
*/
if( ssl->session_out != NULL &&
mfl_code_to_length[ssl->session_out->mfl_code] < max_len )
{
max_len = mfl_code_to_length[ssl->session_out->mfl_code];
}
n = ( len < max_len) ? len : max_len;
if( ssl->out_left != 0 )
{

View File

@ -57,8 +57,20 @@
#define DFL_MIN_VERSION -1
#define DFL_MAX_VERSION -1
#define DFL_AUTH_MODE SSL_VERIFY_OPTIONAL
#define DFL_MFL_CODE SSL_MAX_FRAG_LEN_NONE
#define GET_REQUEST "GET %s HTTP/1.0\r\n\r\n"
#define LONG_HEADER "User-agent: blah-blah-blah-blah-blah-blah-blah-blah-" \
"-01--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
"-02--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
"-03--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
"-04--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
"-05--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
"-06--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
"-07--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-END\r\n"
/* Uncomment LONG_HEADER in the definition of GET_REQUEST to test sending
* longer paquets (for fragmentation purposes) */
#define GET_REQUEST "GET %s HTTP/1.0\r\n" /* LONG_HEADER */ "\r\n"
/*
* global options
@ -81,6 +93,7 @@ struct options
int min_version; /* minimum protocol version accepted */
int max_version; /* maximum protocol version accepted */
int auth_mode; /* verify mode for connection */
unsigned char mfl_code; /* code for maximum fragment length */
} opt;
static void my_debug( void *ctx, int level, const char *str )
@ -176,6 +189,8 @@ static int my_verify( void *data, x509_cert *crt, int depth, int *flags )
" options: ssl3, tls1, tls1_1, tls1_2\n" \
" auth_mode=%%s default: \"optional\"\n" \
" options: none, optional, required\n" \
" max_frag_len=%%d default: 16384 (tls default)" \
" options: 512, 1024, 2048, 4096" \
USAGE_PSK \
"\n" \
" force_ciphersuite=<name> default: all enabled\n"\
@ -197,7 +212,7 @@ int main( int argc, char *argv[] )
#else
int main( int argc, char *argv[] )
{
int ret = 0, len, server_fd, i;
int ret = 0, len, server_fd, i, written, frags;
unsigned char buf[1024];
#if defined(POLARSSL_KEY_EXCHANGE_PSK_ENABLED)
unsigned char psk[256];
@ -265,6 +280,7 @@ int main( int argc, char *argv[] )
opt.min_version = DFL_MIN_VERSION;
opt.max_version = DFL_MAX_VERSION;
opt.auth_mode = DFL_AUTH_MODE;
opt.mfl_code = DFL_MFL_CODE;
for( i = 1; i < argc; i++ )
{
@ -387,6 +403,19 @@ int main( int argc, char *argv[] )
else
goto usage;
}
else if( strcmp( p, "max_frag_len" ) == 0 )
{
if( strcmp( q, "512" ) == 0 )
opt.mfl_code = SSL_MAX_FRAG_LEN_512;
else if( strcmp( q, "1024" ) == 0 )
opt.mfl_code = SSL_MAX_FRAG_LEN_1024;
else if( strcmp( q, "2048" ) == 0 )
opt.mfl_code = SSL_MAX_FRAG_LEN_2048;
else if( strcmp( q, "4096" ) == 0 )
opt.mfl_code = SSL_MAX_FRAG_LEN_4096;
else
goto usage;
}
else
goto usage;
}
@ -592,6 +621,8 @@ int main( int argc, char *argv[] )
ssl_set_endpoint( &ssl, SSL_IS_CLIENT );
ssl_set_authmode( &ssl, opt.auth_mode );
ssl_set_max_frag_len( &ssl, opt.mfl_code );
ssl_set_rng( &ssl, ctr_drbg_random, &ctr_drbg );
ssl_set_dbg( &ssl, my_debug, stdout );
ssl_set_bio( &ssl, net_recv, &server_fd,
@ -682,7 +713,9 @@ int main( int argc, char *argv[] )
len = sprintf( (char *) buf, GET_REQUEST, opt.request_page );
while( ( ret = ssl_write( &ssl, buf, len ) ) <= 0 )
for( written = 0, frags = 0; written < len; written += ret, frags++ )
{
while( ( ret = ssl_write( &ssl, buf + written, len - written ) ) <= 0 )
{
if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
{
@ -690,9 +723,10 @@ int main( int argc, char *argv[] )
goto exit;
}
}
}
len = ret;
printf( " %d bytes written\n\n%s", len, (char *) buf );
buf[written] = '\0';
printf( " %d bytes written in %d fragments\n\n%s\n", written, frags, (char *) buf );
/*
* 7. Read the HTTP response

View File

@ -68,11 +68,22 @@
#define DFL_MIN_VERSION -1
#define DFL_MAX_VERSION -1
#define DFL_AUTH_MODE SSL_VERIFY_OPTIONAL
#define DFL_MFL_CODE SSL_MAX_FRAG_LEN_NONE
#define LONG_RESPONSE "<p>01-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
"02-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
"03-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
"04-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
"05-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
"06-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
"07-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah</p>\r\n"
/* Uncomment LONG_RESPONSE at the end of HTTP_RESPONSE to test sending longer
* packets (for fragmentation purposes) */
#define HTTP_RESPONSE \
"HTTP/1.0 200 OK\r\nContent-Type: text/html\r\n\r\n" \
"<h2>PolarSSL Test Server</h2>\r\n" \
"<p>Successful connection using: %s</p>\r\n"
"<p>Successful connection using: %s</p>\r\n" // LONG_RESPONSE
/*
* global options
@ -93,6 +104,7 @@ struct options
int min_version; /* minimum protocol version accepted */
int max_version; /* maximum protocol version accepted */
int auth_mode; /* verify mode for connection */
unsigned char mfl_code; /* code for maximum fragment length */
} opt;
static void my_debug( void *ctx, int level, const char *str )
@ -147,6 +159,8 @@ static void my_debug( void *ctx, int level, const char *str )
" options: ssl3, tls1, tls1_1, tls1_2\n" \
" auth_mode=%%s default: \"optional\"\n" \
" options: none, optional, required\n" \
" max_frag_len=%%d default: 16384 (tls default)" \
" options: 512, 1024, 2048, 4096" \
USAGE_PSK \
"\n" \
" force_ciphersuite=<name> default: all enabled\n"\
@ -168,7 +182,7 @@ int main( int argc, char *argv[] )
#else
int main( int argc, char *argv[] )
{
int ret = 0, len;
int ret = 0, len, written, frags;
int listen_fd;
int client_fd = -1;
unsigned char buf[1024];
@ -250,6 +264,7 @@ int main( int argc, char *argv[] )
opt.min_version = DFL_MIN_VERSION;
opt.max_version = DFL_MAX_VERSION;
opt.auth_mode = DFL_AUTH_MODE;
opt.mfl_code = DFL_MFL_CODE;
for( i = 1; i < argc; i++ )
{
@ -368,6 +383,19 @@ int main( int argc, char *argv[] )
else
goto usage;
}
else if( strcmp( p, "max_frag_len" ) == 0 )
{
if( strcmp( q, "512" ) == 0 )
opt.mfl_code = SSL_MAX_FRAG_LEN_512;
else if( strcmp( q, "1024" ) == 0 )
opt.mfl_code = SSL_MAX_FRAG_LEN_1024;
else if( strcmp( q, "2048" ) == 0 )
opt.mfl_code = SSL_MAX_FRAG_LEN_2048;
else if( strcmp( q, "4096" ) == 0 )
opt.mfl_code = SSL_MAX_FRAG_LEN_4096;
else
goto usage;
}
else
goto usage;
}
@ -562,6 +590,8 @@ int main( int argc, char *argv[] )
ssl_set_endpoint( &ssl, SSL_IS_SERVER );
ssl_set_authmode( &ssl, opt.auth_mode );
ssl_set_max_frag_len( &ssl, opt.mfl_code );
ssl_set_rng( &ssl, ctr_drbg_random, &ctr_drbg );
ssl_set_dbg( &ssl, my_debug, stdout );
@ -748,7 +778,7 @@ reset:
}
len = ret;
printf( " %d bytes read\n\n%s", len, (char *) buf );
printf( " %d bytes read\n\n%s\n", len, (char *) buf );
if( memcmp( buf, "SERVERQUIT", 10 ) == 0 )
goto exit;
@ -767,7 +797,9 @@ reset:
len = sprintf( (char *) buf, HTTP_RESPONSE,
ssl_get_ciphersuite( &ssl ) );
while( ( ret = ssl_write( &ssl, buf, len ) ) <= 0 )
for( written = 0, frags = 0; written < len; written += ret, frags++ )
{
while( ( ret = ssl_write( &ssl, buf + written, len - written ) ) <= 0 )
{
if( ret == POLARSSL_ERR_NET_CONN_RESET )
{
@ -781,9 +813,10 @@ reset:
goto exit;
}
}
}
len = ret;
printf( " %d bytes written\n\n%s\n", len, (char *) buf );
buf[written] = '\0';
printf( " %d bytes written in %d fragments\n\n%s\n", written, frags, (char *) buf );
ret = 0;
goto reset;