Query: mcookie
OS: linux
Section: 1
Format: Original Unix Latex Style Formatted with HTML and a Horizontal Scroll Bar
MCOOKIE(1) Linux Programmer's Manual MCOOKIE(1)NAMEmcookie - generate magic cookies for xauthSYNOPSISmcookie [-v] [-f filename]DESCRIPTIONmcookie generates a 128-bit random hexadecimal number for use with the X authority system. Typical usage: xauth add :0 . `mcookie` The "random" number generated is actually the output of the MD5 message digest fed with various pieces of random information: the current time, the process id, the parent process id, the contents of an input file (if -f is specified), and several bytes of information from the first of the following devices which is present: /dev/random, /dev/urandom, files in /proc, /dev/audio.BUGSThe entropy in the generated 128-bit is probably quite small (and, therefore, vulnerable to attack) unless a non-pseudorandom number gener- ator is used (e.g., /dev/random under Linux). It is assumed that none of the devices opened will block.FILES/dev/random /dev/urandom /dev/audio /proc/stat /proc/loadavgSEE ALSOX(1), xauth(1), md5sum(1)AVAILABILITYThe mcookie command is part of the util-linux package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux/. 25 September 1995 MCOOKIE(1)