| .\" Copyright (C) 2001 Jeff Garzik -- jgarzik@pobox.com |
| .\" |
| .TH RNGD 8 "March 2001" "@PACKAGE@ @VERSION@" |
| |
| .SH NAME |
| rngd \- Check and feed random data from hardware device to kernel random device |
| |
| .SH SYNOPSIS |
| .B rngd |
| [\fB\-b\fR, \fB\-\-background\fR] |
| [\fB\-f\fR, \fB\-\-foreground\fR] |
| [\fB\-o\fR, \fB\-\-random-device=\fIfile\fR] |
| [\fB\-p\fR, \fB\-\-pid-file=\fIfile\fR] |
| [\fB\-r\fR, \fB\-\-rng-device=\fIfile\fR] |
| [\fB\-s\fR, \fB\-\-random-step=\fInnn\fR] |
| [\fB\-W\fR, \fB\-\-fill-watermark=\fInnn\fR] |
| [\fB\-d\fR, \fB\-\-no-drng=\fI1|0\fR] |
| [\fB\-n\fR, \fB\-\-no-tpm=\fI1|0\fR] |
| [\fB\-q\fR, \fB\-\-quiet\fR] |
| [\fB\-v\fR, \fB\-\-verbose\fR] |
| [\fB\-?\fR, \fB\-\-help\fR] |
| [\fB\-V\fR, \fB\-\-version\fR] |
| .RI |
| |
| .SH DESCRIPTION |
| This daemon feeds data from a random number generator to the kernel's |
| random number entropy pool, after first checking the data to ensure that |
| it is properly random. |
| .PP |
| The \fB\-f\fR or \fB\-\-foreground\fR options can be used to tell |
| \fBrngd\fR to avoid forking on startup. This is typically used for |
| debugging. The \fB\-b\fR or \fB\-\-background\fR options, which fork and put |
| \fBrngd\fR into the background automatically, are the default. |
| .PP |
| The \fB\-r\fR or \fB\-\-rng-device\fR options can be used to select an |
| alternate source of input, besides the default /dev/hwrandom. |
| The \fB\-o\fR or \fB\-\-random-device\fR options can be used to select |
| an alternate entropy output device, besides the default /dev/random. |
| Note that this device must support the Linux kernel /dev/random |
| ioctl API. |
| .PP |
| |
| .SH OPTIONS |
| .TP |
| \fB\-b\fR, \fB\-\-background\fR |
| Become a daemon (default) |
| .TP |
| \fB\-f\fR, \fB\-\-foreground\fR |
| Do not fork and become a daemon |
| .TP |
| \fB\-p\fI file\fR, \fB\-\-pid-file=\fIfile\fR |
| File used for recording daemon PID, and multiple exclusion |
| (default: /var/run/rngd.pid) |
| .TP |
| \fB\-o\fI file\fR, \fB\-\-random-device=\fIfile\fR |
| Kernel device used for random number output |
| (default: /dev/random) |
| .TP |
| \fB\-r\fI file\fR, \fB\-\-rng-device=\fIfile\fR |
| Kernel device used for random number input |
| (default: /dev/hwrandom) |
| .TP |
| \fB\-s\fI nnn\fR, \fB\-\-random-step=\fInnn\fR |
| Number of bytes written to random-device at a time (default: 64) |
| .TP |
| \fB\-W\fI n\fR, \fB\-\-fill\-watermark=\fInnn\fR |
| Once we start doing it, feed entropy to \fIrandom-device\fR until at least |
| \fIfill-watermark\fR bits of entropy are available in its entropy pool (default: 2048). |
| Setting this too high will cause \fIrngd\fR to dominate the contents of the |
| entropy pool. Low values will hurt system performance during entropy |
| starves. Do not set \fIfill-watermark\fR above the size of the |
| entropy pool (usually 4096 bits). |
| .TP |
| \fB\-d\fI 1|0\fR, \fB\-\-no-drng=\fI1|0\fR |
| Do not use drng as a source of random number input (default:0) |
| .TP |
| \fB\-n\fI 1|0\fR, \fB\-\-no-tpm=\fI1|0\fR |
| Do not use tpm as a source of random number input (default:0) |
| .TP |
| \fB\-q\fR, \fB\-\-quiet\fR |
| Suppress error messages |
| .TP |
| \fB\-v\fR, \fB\-\-verbose\fR |
| Report available entropy sources |
| .TP |
| \fB\-?\fR, \fB\-\-help\fR |
| Give a short summary of all program options. |
| .TP |
| \fB\-V\fR, \fB\-\-version\fR |
| Print program version |
| |
| .SH AUTHORS |
| Philipp Rumpf |
| .br |
| Jeff Garzik \- jgarzik@pobox.com |
| .br |
| Matt Sottek |
| .br |
| Brad Hill |