user_guide.html

TTYLINUX迷你代码 TTYLINUX迷你代码

To convert an OpenSSH key stored in <tt>&nbsp;/.ssh/id_rsa</tt>, do:

<p>
<pre>
  dropbearconvert openssh dropbear ~/.ssh/id\_rsa ~/.ssh/id\_rsa.db
</pre>

<p>
The new key will be stored in <tt>&nbsp;/.ssh/id_rsa.db</tt>. You can
use the <tt>-i</tt> switch to <tt>dbclient</tt> to make it use your
new key for authentication. The public key part of the old OpenSSH
key can be used as-is for pasting into your <tt>&nbsp;/.ssh/authorized_keys</tt>
file. Conversion is only needed for the private key.

<p>
To create a new RSA key to store in <tt>&nbsp;/.ssh/id_rsa.db</tt>, you
can use the following command:

<p>
<pre>
  dropbearkey -t rsa -f ~/.ssh/id\_rsa.db
</pre>

<p>
The public key part of the new key will be printed to the screen.
You can put it into the <tt>&nbsp;/.ssh/authorized_keys</tt> file on all
machines where you want to be able to login using your new private
key stored in <tt>&nbsp;/.ssh/id_rsa.db</tt>. You can create a DSS key
instead of an RSA key by using <tt>-t</tt> <tt>dss</tt> instead of
<tt>-t</tt> <tt>rsa</tt>. Should you lose the public key, you can always
get it back by using the private key and the <tt>-y</tt> switch
to <tt>dropbearkey</tt>:

<p>
<pre>
  dropbearkey -y -f ~/.ssh/id\_rsa.db
</pre>

<p>
If you want to use <tt>scp</tt> to copy files from another machine,
the standard <tt>scp</tt> program from OpenSSH is included with
<tt>dropbear</tt> and ttylinux.

<p>

<h2><a name="SECTION00045000000000000000">
<span class="arabic">3</span>.<span class="arabic">5</span> Setting up network devices</a>
</h2>

<p>
Basic network setting are located in the <tt>/etc/network.conf</tt> file. In
that file, you can globally disable or enable networking. Also, it is
possible to specify a gateway address. If configured, ttylinux will
setup a default route to the gateway on bootup. This is mainly useful
if you don't use modem or ISDN dialup. If you do use dialup, the
default route will be overwritten once you start a dialup connection.

<p>
Note that loopback networking via the <tt>lo</tt> device is always enabled.
The setting in <tt>/etc/network.conf</tt> only covers devices that can contact
the outside world.

<p>
To set up a network device, go to the directory <tt>/etc/network.d</tt> and
copy  the file <tt>sample</tt> found there to a file named <tt>interface.dev</tt>.
For example, if you want to setup the device <tt>eth0</tt>, name the file
<tt>interface.eth0</tt>:

<p>
<pre>
  cp sample interface.eth0
</pre>

<p>
Now edit the new file to adjust the settings for the device. You  can
either let the system use the DHCP protocol to obtain the settings
from a DHCP server or you can set the IP address and other parameters
manually within the file.

<p>

<h2><a name="SECTION00046000000000000000">
<span class="arabic">3</span>.<span class="arabic">6</span> Using the firewall</a>
</h2>

<p>
The default settings of the ttylinux firewall script assume that the
network interface to the rest of the world is called <tt>ippp0</tt> or
<tt>ppp0</tt>, depending  on whether you use ISDN or modem dialup. By default,
the firewall will allow the world to access the SSH server, but will
deny access to the telnet server. Other incoming connection attempts
will also be denied and logged (rate limited to an average of 3 messages
per hour), except for connections to the <tt>ftp-data</tt> port, which is
used for active FTP sessions and allowed in. This applies to TCP
connections. For the UDP protocol, incoming packets to ports above 1024
are allowed. Also, the outside world is not allowed to ping the ttylinux
machine.

<p>
Outgoing traffic is not firewalled at all.

<p>
You can change the settings of the firewall in <tt>/etc/firewall.conf</tt>.
The only configuration options are whether to allow or deny access to
the SSH and telnet servers.

<p>
Note that this firewall script is very simple and assumes that local
users are always trusted. There is no protection against users
running server daemons on UDP ports above 1024. If you don't trust
your users, this firewall script is not enough for you! Also note
that only the <tt>ppp0</tt> or <tt>ippp0</tt> device is protected, all other
interfaces are not firewalled at all.

<p>

<h2><a name="SECTION00047000000000000000">
<span class="arabic">3</span>.<span class="arabic">7</span> Shell environment</a>
</h2>

<p>
The default shell used by ttylinux is GNU bash. You can change the
startup environment (variables, aliases, etc) in <tt>/etc/profile</tt>.
You can also put files into the directory <tt>/etc/profile.d</tt> - all
readable files in that directory will be sourced by <tt>bash</tt> when you
login on the ttylinux machine.

<p>
Using <tt>/etc/profile.d</tt> is a good choice for your own personal changes.
You may want to update to a new version of ttylinux sometime later,
and you could end up loosing all your changes to <tt>/etc/profile</tt>
if you forget to make a backup. In <tt>/etc/profile.d</tt>, your changes are
safe.

<p>

<h2><a name="SECTION00048000000000000000">
<span class="arabic">3</span>.<span class="arabic">8</span> Package Management</a>
</h2>

<p>
Package management is handled by a shell script called <tt>pacman</tt>
(a pun on Package Manager). Its options are somewhat similar to Red
Hat's package manager RPM. It is possible to install and remove
packages and to query the database of installed packages and files.

<p>
The binary packages used by ttylinux are basically <tt>tar</tt>
archives compressed with the <tt>bzip2</tt> algorithm. You can download
all the packages that normally come with the distribution from
the downloads page on the ttylinux homepage. You may need to
do that if you remove a package on a running ttylinux system
and later want to reinstall it.

<p>
To install the package <tt>bash-3.0-2.bin.tbz</tt>, you would
use the following command:

<p>
<pre>
  pacman -i bash-3.0-2.bin.tbz
</pre>

<p>
You can also install a package from standard input, which can
be useful for forming a pipe with the <tt>wget</tt> program. This allows
you to install a package from the network without having to
store it on the ttylinux system. For example, to download
the <tt>bash</tt> package from the hypothetical <tt>foo.org</tt>
web server, you would use:

<p>
<pre>
  wget http:/foo.org/bash-3.0-2.bin.tbz -O - | pacman -i -
</pre>

<p>
Three different options are available for querying the database
of installed packages and files. To get a list of all installed
packages, run

<p>
<pre>     
  pacman -qa
</pre>

<p>
To find out which package the file <tt>/bin/login</tt> belongs to, use

<p>
<pre>     
  pacman -qf /bin/login
</pre>

<p>
To list all files from the <tt>e2fsprogs</tt> package, run

<p>
<pre>
  pacman -ql e2fsprogs
</pre>

<p>
If you want to remove a package, you can do so by use of the <tt>-e</tt>
option. To remove the <tt>isdn4k-utils</tt> package, you would
use the following command:

<p>
<pre>
  pacman -e isdn4k-utils
</pre>

<p>
You can also use the <tt>-v</tt> option to get verbose output during
installation and removal of packages. <tt>pacman</tt> will then list
all the files it has installed or removed.

<p>
The <tt>pacman</tt> script get its knowledge about installed packages
and files from the directory <tt>/var/log/packages</tt>, where you
can find one file per installed package. The file contains a
listing of all files that belong to that particular package.
<tt>pacman</tt> will not notice when you delete files by hand, it
exclusively uses information found in <tt>/var/log/packages</tt>.

<p>

<h2><a name="SECTION00049000000000000000">
<span class="arabic">3</span>.<span class="arabic">9</span> Using <tt>devfs</tt> (no longer supported)</a>
</h2>

<p>
Previous versions of ttylinux had support for running Linux kernels
with the <tt>devfs</tt> device filesystem enabled. However, starting from 
the 2.6 kernel, <tt>devfs</tt> is considered obsolete by the main kernel
developers. A replacement solution is called <tt>udev</tt> and runs
completely in user space. As a consequence, I have dropped the minimal
<tt>devfs</tt> support that was present in ttylinux. As of now, <tt>udev</tt>
integration is not planned because I  still want to support pre-2.6
kernels, but that may change in the future.

<p>

<h1><a name="SECTION00050000000000000000">
<span class="arabic">4</span> Contact</a>
</h1>

<p>
If you have bug reports, suggestions, or anything else about ttylinux
that you think is important, feel free to contact me. You can reach
me by email at:

<p>
<pre>     
       Pascal Schmidt &lt;[e-mail]&gt;
</pre>

<p>
See the file <tt>AUTHORS</tt> in the ttylinux distribution for a list of
people who contributed ideas, bug reports, or code so far.

<p>

<p>

<h1><a name="SECTION00060000000000000000"></a>
<a name="makecdrom"></a>
<br>
A. How to create a bootable ttylinux CD
</h1>

<p>
Please note: the following instructions are for putting together
a 2.88 MB floppy image that can be put onto a bootable CD-ROM.
This is a different approach to that used by the official
ttylinux CD-ROM version. The recipe below produces a smaller
image than the official one, but the distribution installer
will <b>not</b> work with the smaller images. There is a script
called <tt>mkttyiso</tt> that is provided with the binary and source
tarball versions of the distribution that can be used to put
together the larger, installer-compatible CD-ROM images.

<p>
To follow the instructions, you need the following programs on your
working  system: <tt>mkisofs</tt>, <tt>mkdosfs</tt>, and <tt>syslinux</tt>.
<tt>mkdosfs</tt> is usually found inside a package called <tt>dosfstools</tt>.

<p>
You  will  need the ttylinux filesystem image <tt>rootfs.gz</tt> and a Linux
kernel image (the result of a <tt>make</tt> <tt>zImage</tt> or <tt>make</tt>
<tt>bzImage</tt>). I assume you have these files in your current working
directory and the kernel image file is called <tt>vmlinuz</tt>. The
following instructions will only work for <tt>root</tt>, not normal users.

<p>
First, go through the rest of this user guide and do all the
customization you want to do. Once ttylinux is burned onto the CD,
you don't get any further chances to change anything.

<p>
Now we start preparing the CD image.

<p>
<pre>     
  mkdir mnt
  mkdir -p iso/boot
  dd if=/dev/zero of=image bs=10k count=288
  mkdosfs image
  syslinux image
  mount -o loop image mnt
  cp vmlinuz mnt/linux
  rdev mnt/linux /dev/ram0
  cp rootfs.gz mnt
</pre>

<p>
At this point, we have created an image file resembling a 2.88 megabyte
floppy disk, <tt>syslinux</tt> has put a bootloader onto this image, we
have mounted the image on the <tt>mnt</tt> directory and copied our kernel
image and filesystem image files onto the disk image. We also told
the kernel to expect the root filesystem on <tt>/dev/ram0</tt> when booting.

<p>
Now we need to create a <tt>syslinux.cfg</tt> configuration file on the disk
image.

<p>
<pre>     
  vi mnt/syslinux.cfg
</pre>

<p>
In this file, place the line

<p>
<pre>     
  append initrd=rootfs.gz
</pre>

<p>
If you need to pass kernel parameters to your kernel, do this on  the
same append line. For example, if you need to pass <tt>idebus=33</tt>,
your line should be

<p>
<pre>     
  append initrd=rootfs.gz idebus=33
</pre>

<p>
Now we are finished creating the disk image we need for making a
bootable CD. Let's start putting together the ISO image.

<p>
<pre>     
  umount mnt
  cp image iso/boot/boot.img
</pre>

<p>
The boot image itself is only 2.88 megabytes, so you will have extra
space available. You can mount the CD after booting to get access to
all the files you put on the ISO image in addition to the <tt>boot.img</tt>
file. Simply put anything you want into the <tt>iso</tt> directory now. Once
you are done with that, do:

<p>
<pre>     
  cd iso
  mkisofs -r -b boot/boot.img -c boot/boot.cat -o ../bootcd.iso .
  cd ..
</pre>

<p>
Congratulations, you finished the job of creating a bootable ISO
image with ttylinux on it. All you need to do now is use some CD
burning program to put the <tt>bootcd.iso</tt> image on a real CD.
You could also save the <tt>iso/boot/boot.img</tt> file and use
it to make bootable discs out of all the ISO images you create -
all that is needed is about 3 megabytes of free space on the
CD.

<p>
<br><hr>

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