git://cygwin.com / cygwin-apps / cygutils.git / blame
| Commit | Line | Data |
|---|---|---|
| eb7cdcb6 CW |
1 | .\" mcookie.1 -- |
| 2 | .\" Public Domain 1995 Rickard E. Faith (faith@cs.unc.edu) | |
| 3 | .TH MCOOKIE 1 "25 September 1995" "" "Linux Programmer's Manual" | |
| 4 | .SH NAME | |
| 5 | mcookie \- generate magic cookies for xauth | |
| 6 | .SH SYNOPSIS | |
| 7 | .BI "mcookie [\-v] [\-f " filename " ]" | |
| 8 | .SH DESCRIPTION | |
| 9 | .B mcookie | |
| 10 | generates a 128-bit random hexadecimal number for use with the X authority | |
| 11 | system. Typical usage: | |
| 12 | .RS | |
| 13 | xauth add :0 . `mcookie` | |
| 14 | .RE | |
| 15 | .PP | |
| 16 | The "random" number generated is actually the output of the MD5 message | |
| 17 | digest fed with various piece of random information: the current time, the | |
| 18 | process id, the parent process id, the contents of an input file (if | |
| 19 | .B \-f | |
| 20 | is specified), and several bytes of information from the first of the | |
| 21 | following devices which is present: | |
| 22 | .IR /dev/random , | |
| 23 | .IR /dev/urandom , | |
| 24 | files in | |
| 25 | .IR /proc , | |
| 26 | .IR /dev/audio . | |
| 27 | .SH BUGS | |
| 28 | The entropy in the generated 128-bit is probably quite small (and, | |
| 29 | therefore, vulnerable to attack) unless a non-pseudorandom number generator | |
| 30 | is used (e.g., | |
| 31 | .I /dev/random | |
| 32 | under Linux). | |
| 33 | .PP | |
| 34 | It is assumed that none of the devices opened will block. | |
| 35 | .SH FILES | |
| 36 | .I /dev/random | |
| 37 | .br | |
| 38 | .I /dev/urandom | |
| 39 | .br | |
| 40 | .I /dev/audio | |
| 41 | .br | |
| 42 | .I /proc/stat | |
| 43 | .br | |
| 44 | .I /proc/loadavg | |
| 45 | .SH "SEE ALSO" | |
| 46 | .BR X (1), | |
| 47 | .BR xauth (1), | |
| 48 | .BR md5sum (1) |