#! /bin/sh # this program collects some entropy from the system # into the file "my_random_file" and outputs the 16-bit # Unix 'sum' checksum (seems to be the only portable way # to get true entropy with a shell script). # Apparently, on FreeBSD /dev/random does not block (???), must make sure # we really got something rather than nothing. rnd_tst=no /bin/rm -f ./my_random_file 2>/dev/null if test -r "/dev/urandom"; then if test -c "/dev/urandom"; then dd if=/dev/urandom ibs=1 count=4 > my_random_file 2>/dev/null nsum=`sum ./my_random_file | awk '{print $1 }' | sed 's%^0*%%g' 2>/dev/null` if test x$nsum != x; then rnd_tst=yes fi fi fi if test x$rnd_tst = xno; then if test -r "/dev/srandom"; then if test -c "/dev/srandom"; then dd if=/dev/srandom ibs=1 count=4 > my_random_file 2>/dev/null nsum=`sum ./my_random_file | awk '{print $1 }' | sed 's%^0*%%g' 2>/dev/null` if test x$nsum != x; then rnd_tst=yes fi fi fi fi if test x$rnd_tst = xno; then # touch ./my_random_file # if test -r "/usr/ucb/vmstat"; then /usr/ucb/vmstat >> my_random_file 2>/dev/null fi if test -r "/bin/vmstat"; then /bin/vmstat >> my_random_file 2>/dev/null fi if test -r "/sbin/vmstat"; then /sbin/vmstat >> my_random_file 2>/dev/null fi if test -r "/usr/bin/vmstat"; then /usr/bin/vmstat >> my_random_file 2>/dev/null fi if test -r "/usr/sbin/vmstat"; then /usr/sbin/vmstat >> my_random_file 2>/dev/null fi if test -r "/usr/local/bin/vmstat"; then /usr/local/bin/vmstat >> my_random_file 2>/dev/null fi # if test -r "/usr/ucb/netstat"; then /usr/ucb/netstat -n >> my_random_file 2>/dev/null fi if test -r "/bin/netstat"; then /bin/netstat -n >> my_random_file 2>/dev/null fi if test -r "/sbin/netstat"; then /sbin/netstat -n >> my_random_file 2>/dev/null fi if test -r "/usr/bin/netstat"; then /usr/bin/netstat -n >> my_random_file 2>/dev/null fi if test -r "/usr/sbin/netstat"; then /usr/sbin/netstat -n >> my_random_file 2>/dev/null fi if test -r "/usr/local/bin/netstat"; then /usr/local/bin/netstat -n >> my_random_file 2>/dev/null fi # # if test -r "/usr/ucb/ps"; then /usr/ucb/ps -ef >> my_random_file 2>/dev/null fi if test -r "/bin/ps"; then /bin/ps -ef >> my_random_file 2>/dev/null fi if test -r "/sbin/ps"; then /sbin/ps -ef >> my_random_file 2>/dev/null fi if test -r "/usr/bin/ps"; then /usr/bin/ps -ef >> my_random_file 2>/dev/null fi if test -r "/usr/sbin/ps"; then /usr/sbin/ps -ef >> my_random_file 2>/dev/null fi if test -r "/usr/local/bin/ps"; then /usr/local/bin/ps -ef >> my_random_file 2>/dev/null fi # # if test -r "/usr/ucb/arp"; then /usr/ucb/arp -a >> my_random_file 2>/dev/null fi if test -r "/bin/arp"; then /bin/arp -a >> my_random_file 2>/dev/null fi if test -r "/sbin/arp"; then /sbin/arp -a >> my_random_file 2>/dev/null fi if test -r "/usr/bin/arp"; then /usr/bin/arp -a >> my_random_file 2>/dev/null fi if test -r "/usr/sbin/arp"; then /usr/sbin/arp -a >> my_random_file 2>/dev/null fi if test -r "/usr/local/bin/arp"; then /usr/local/bin/arp -a >> my_random_file 2>/dev/null fi # # if test -r "/usr/ucb/w"; then /usr/ucb/w >> my_random_file 2>/dev/null fi if test -r "/bin/w"; then /bin/w >> my_random_file 2>/dev/null fi if test -r "/sbin/w"; then /sbin/w >> my_random_file 2>/dev/null fi if test -r "/usr/bin/w"; then /usr/bin/w >> my_random_file 2>/dev/null fi if test -r "/usr/sbin/w"; then /usr/sbin/w >> my_random_file 2>/dev/null fi if test -r "/usr/local/bin/w"; then /usr/local/bin/w >> my_random_file 2>/dev/null fi # # Don't use (NFS problems ahead) # # if test -r "/usr/ucb/df"; then # /usr/ucb/df >> my_random_file 2>/dev/null # fi # if test -r "/bin/df"; then # /bin/df >> my_random_file 2>/dev/null # fi # if test -r "/sbin/df"; then # /sbin/df >> my_random_file 2>/dev/null # fi # if test -r "/usr/bin/df"; then # /usr/bin/df >> my_random_file 2>/dev/null # fi # if test -r "/usr/sbin/df"; then # /usr/sbin/df >> my_random_file 2>/dev/null # fi # if test -r "/usr/local/bin/df"; then # /usr/local/bin/df >> my_random_file 2>/dev/null # fi # # if test -r "/usr/ucb/free"; then /usr/ucb/free >> my_random_file 2>/dev/null fi if test -r "/bin/free"; then /bin/free >> my_random_file 2>/dev/null fi if test -r "/sbin/free"; then /sbin/free >> my_random_file 2>/dev/null fi if test -r "/usr/bin/free"; then /usr/bin/free >> my_random_file 2>/dev/null fi if test -r "/usr/sbin/free"; then /usr/sbin/free >> my_random_file 2>/dev/null fi if test -r "/usr/local/bin/free"; then /usr/local/bin/free >> my_random_file 2>/dev/null fi # # if test -r "/usr/ucb/uptime"; then /usr/ucb/uptime >> my_random_file 2>/dev/null fi if test -r "/bin/uptime"; then /bin/uptime >> my_random_file 2>/dev/null fi if test -r "/sbin/uptime"; then /sbin/uptime >> my_random_file 2>/dev/null fi if test -r "/usr/bin/uptime"; then /usr/bin/uptime >> my_random_file 2>/dev/null fi if test -r "/usr/sbin/uptime"; then /usr/sbin/uptime >> my_random_file 2>/dev/null fi if test -r "/usr/local/bin/uptime"; then /usr/local/bin/uptime >> my_random_file 2>/dev/null fi # # if test -r "/usr/ucb/procinfo"; then /usr/ucb/procinfo -a >> my_random_file 2>/dev/null fi if test -r "/bin/procinfo"; then /bin/procinfo -a >> my_random_file 2>/dev/null fi if test -r "/sbin/procinfo"; then /sbin/procinfo -a >> my_random_file 2>/dev/null fi if test -r "/usr/bin/procinfo"; then /usr/bin/procinfo -a >> my_random_file 2>/dev/null fi if test -r "/usr/sbin/procinfo"; then /usr/sbin/procinfo -a >> my_random_file 2>/dev/null fi if test -r "/usr/local/bin/procinfo"; then /usr/local/bin/procinfo -a >> my_random_file 2>/dev/null fi # nsum=`sum ./my_random_file | awk '{print $1 }' | sed 's%^0*%%g' 2>/dev/null` # fi # # 'sum' is portable, but only 16 bit # /bin/rm -f ./my_random_file 2>/dev/null echo $nsum