View source for Php www-data program that creates a crontab and calls a C program that executes root commands to copy it into crontabs and install it

Here's an example of a crontab that does something every minute 
 #m h md m wd user command
 * * * * * /bin/echo " siteNoHstilloobar $(date) " >> /usr/local/docs/testcron.txt

you can see in testcron.txt  and know its running from cron by seeing it in the log by running
 root@server1 ~# tail /var/log/syslog

refp from Stackoverflow had a prg to [http://stackoverflow.com/questions/8532304/execute-root-commands-via-php execute-root-commands-via-php] So I could put commands in wrapper.c and they would execute with root permissions. This allowed me to replace the user:sitebuil crontab and install it. Did this and put wrapper.c and installCron (the compiled version) here
 root@server1 sitebuil/scripts# gcc wrapper.c -o installCron
wrapper.c
<syntaxhighlight>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
int
main (int argc, char *argv[])
{setuid (0);
 /* WARNING: Only use an absolute path to the script to execute,
  *          a malicious user might fool the binary and execute
  *          arbitary commands if not.
  * */
 system ("cp /usr/local/docs/newSitebuilCron /var/spool/cron/crontabs/sitebuil");
 system ("/usr/bin/crontab -u sitebuil /var/spool/cron/crontabs/sitebuil");
 return 0;
}
</syntaxhighlight>
This create a crontab file and installs it from php www-data http://pathboston.com/zstill/wwwcron.php
<syntaxhighlight>
<?php
//testfile to have ph create a newSitebuilCron file and replace /var/spool/cron/crontab/sitebuil
$fp = fopen('/usr/local/docs/newSitebuilCron', 'w');
fwrite($fp, 
'#m h md wd user cmd'.PHP_EOL.
'* * * * * /bin/echo " first line $(date) " >> /usr/local/docs/testcron.txt'.PHP_EOL.
'* * * * * /bin/echo " second line $(date) " >> /usr/local/docs/testcron.txt'.PHP_EOL
);
fclose($fp);
echo 'it ran';
//wrapper.c compiled -> installCron prog that runs as anybody but executes root commands
//copying usr/local/docs/newSitebuilCron to /var/spool/cron/crontab/sitebuil 
//and then installing the sitebuil crontab 
exec('/home/sitebuil/scripts/installCron');
?>
</syntaxhighlight>