text written from php client to c server only appears on dosconnect - php

Question

I have an ssl server (test) in c - and a client written in php. the server works fine when a client written in c connects, but when the php client (virtually identical to the c client) sends, the message appears on the server only after buffer overflow or disconnect.
why a c program and not a php program would work is a mystery to me.
I've tried buffer control, unblocking, adding nulls to the send string.
php 5.4 centos linux 2.6
i can add code if appropriate - it's quite vanilla. but i thought there might be a difference between the way php handles stream traffic and c. my confidence in my code.
thanks for any thoughts.
#!/usr/local/bin/php
<?php
date_default_timezone_set('America/New_York');
$host = 'localhost';
$port = 9255;
$timeout = 5.0;
function gen_cert($pem_file,$pem_passphrase)
{
// Certificate data:
$dn = array(
"countryName" => "US",
"stateOrProvinceName" => "Texas",
"localityName" => "Houston",
"organizationName" => "<org name>",
"organizationalUnitName" => "Tech",
"commonName" => "kensie2",
"emailAddress" => "<email>"
);
// Generate certificate
$privkey = openssl_pkey_new();
$cert = openssl_csr_new($dn, $privkey);
$cert = openssl_csr_sign($cert, null, $privkey, 365);
// Generate PEM file
$pem = array();
openssl_x509_export($cert, $pem[0]);
openssl_pkey_export($privkey, $pem[1], $pem_passphrase);
openssl_pkey_export($privkey, $pem[1], $pem_passphrase);
$pem = implode($pem);
// Save PEM file
// $pemfile = $filename;
file_put_contents($pem_file, $pem);
chmod($pem_file,0400);
}
$pem_passphrase = 'foozot';
$pem_file = 'test3_client.pem';
if(!file_exists($pem_file))
gen_cert($pem_file,$pem_passphrase);
$context = stream_context_create();
// local_cert must be in PEM format
stream_context_set_option($context, 'tls', 'local_cert', $pem_file);
// Pass Phrase (password) of private key
stream_context_set_option($context, 'tls', 'passphrase', $pem_passphrase);
stream_context_set_option($context, 'tls', 'allow_self_signed', true);
stream_context_set_option($context, 'tls', 'verify_peer', true);
$fp = stream_socket_client('tls://'.$host.':'.$port, $errno, $errstr, $timeout,
STREAM_CLIENT_CONNECT, $context);
if($fp)
{
$buf = fread($fp,8192);
fwrite(STDOUT,"from server: $buf");
// tried this - no difference
// stream_set_write_buffer($fp,0);
// tried this - no difference
// stream_set_blocking($fp,0);
$ary = stream_get_meta_data($fp);
fwrite(STDERR,"meta=" . print_r($ary,true) . "\n");
while(1)
{
$buf = fgets(STDIN);
fwrite(STDOUT,"buf=$buf\n");
if(strstr($buf,"\n") === null)
$buf .= "\n\0";
$er = fwrite($fp, $buf,strlen($buf) + 1);
fwrite(STDERR,posix_strerror(posix_get_last_error()) . "\n");
}
}
else
{
echo "ERROR: $errno - $errstr<br />\n";
}
?>
I'musing code from Professional Linux Network Programming - Chapter 8 - server.c
By Nathan Yocom, plnp#yocom.org modified to prefork. it uses BIO for io.
as a model for the c code. i don't think i can post it without some copyright violation.
it does work. far more tested than my code.