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author | Rob Austein <sra@hactrn.net> | 2016-08-08 17:30:58 -0400 |
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committer | Rob Austein <sra@hactrn.net> | 2016-08-08 17:30:58 -0400 |
commit | 1f75ecd9bc47c12a3c1596497dfaa621a2d16103 (patch) | |
tree | f52166c947154730db2723263bb3bdc845ad1249 /doc/manual/07.RPKI.RP.rpki-rtr.md | |
parent | 7be7c02b6d2f1cec295ebacac49b01c75b6038a4 (diff) |
Move old manual to doc/manual, to make it easier to find other documentation.
Diffstat (limited to 'doc/manual/07.RPKI.RP.rpki-rtr.md')
-rw-r--r-- | doc/manual/07.RPKI.RP.rpki-rtr.md | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/doc/manual/07.RPKI.RP.rpki-rtr.md b/doc/manual/07.RPKI.RP.rpki-rtr.md new file mode 100644 index 00000000..59f6fdb0 --- /dev/null +++ b/doc/manual/07.RPKI.RP.rpki-rtr.md @@ -0,0 +1,150 @@ +# rpki-rtr + +`rpki-rtr` is an implementation of the ["RPKI-router" protocol (RFC-6810)][RFC-6810]. + +`rpki-rtr` depends on [rcynic][] to collect and validate the RPKI data. +`rpki-rtr`'s's job is to serve up that data in a lightweight format suitable +for routers that want to do prefix origin authentication. + +To use `rpki-rtr`, you need to do two things beyond just running `rcynic`: + + 1. You need to [post-process `rcynic`'s output][rpki-rtr] into the data files used by rpki-rtr. The `rcynic-cron` script handles this automatically, so the default installation should already be taking care of this for you. + 2. You need to [set up a listener][rpki-rtr] for the `rpki-rtr` server, using the generated data files. The platform-specific packages for FreeBSD, Debian, and Ubuntu automatically set up a plain TCP listener, but you will have to do something on other platforms, or if you're using a transport protocol other than plain TCP. + +## Post-processing rcynic's output + +`rpki-rtr` is designed to do the translation from raw RPKI data into the rpki- +rtr protocol only once. It does this by pre-computing the answers to all the +queries it is willing to answer for a given data set, and storing them on +disk. `rpki-rtr`'s `cronjob` command handles this computation. + +To set this up, add an invocation of `rpki-rtr cronjob` to the cron job you're +already running to run `rcynic`. As mentioned above, if you're running the +`rcynic-cron` script, this is already being done for you automatically, so you +don't need to do anything. If you've written your own cron script, you'll need +to add something like this to your script: + + /usr/local/bin/rpki-rtr cronjob /var/rcynic/data/authenticated /var/rcynic/rpki-rtr + +`rpki-rtr cronjob` needs write access to a directory where it can store pre- +digested versions of the data it pulls from `rcynic`. In the example above, +the directory `/var/rcynic/rpki-rtr` should be writable by the user ID that is +executing the cron script. + +`rpki-rtr` creates a collection of data files, as well as a subdirectory in +which each instance of `rpki-rtr server` can place a `PF_UNIX` socket file. By +default, `rpki-rtr` creates these files under the directory in which you run +it, but you can change that by specifying the target directory as a second +command line argument, as shown above. + +You should make sure that `rpki-rtr cronjob` runs at least once before +attempting to configure `rpki-rtr server`. Nothing terrible will happen if you +don't do this, but `rpki-rtr server` invocations started before the first +`rpki-rtr cronjob` run may behave oddly. + +## Setting up the rpki-rtr server + +You need to to set up a server listener that invokes `rpki-rtr server`. What +kind of server listener you set up depends on which network protocol you're +using to transport this protocol. `rpki-rtr` is happy to run under inetd, +xinetd, sshd, or pretty much anything -- `rpki-rtr` doesn't really care, it +just reads from `stdin` and writes to `stdout`. + +`rpki-rtr server` should be run as a non-privileged user (it is read-only for +a reason). You may want to set up a separate UNIX userid for this purpose. + +`rpki-rtr server` takes an optional argument specifying the path to its data +directory; if you omit this argument, it uses the directory in in which you +run it. + +The details of how you set up a listener for this vary depending on the +network protocol and the operating system on which you run it. Here are three +examples, for running under `inetd` on FreeBSD, under `sshd`, or as a free- +standing server using `rpki-rtr listener`. + +### Running rpki-rtr server under inetd + +Running under `inetd` with plain TCP is insecure and should only be done for +testing, but you can also run it with TCP-MD5 or TCP-AO, or over IPsec. The +inetd configuration is generally the same, the details of how you set up TCP- +MD5, TCP-AO, or IPsec are platform specific. + +To run under `inetd`, you need to: + + 1. Add an entry to `/etc/services` defining a symbolic name for the port, if one doesn't exist already. At present there is no well-known port defined for this protocol, for this example we'll use port 42420 and the symbolic name `rpki-rtr`. + +> Add to `/etc/services`: + + rpki-rtr 42420/tcp + + 2. Add the service line to `/etc/inetd.conf`: + + rpki-rtr stream tcp nowait nobody /usr/local/bin/rpki-rtr rpki-rtr server /var/rcynic/rpki-rtr + +> This assumes that you want the server to run as user "nobody", which is +generally a safe choice, or you could create a new non-priviledged user for +this purpose. **DO NOT** run the server as root; it shouldn't do anything bad, +but it's a network server that doesn't need root access, therefore it +shouldn't have root access. + +### Running rpki-rtr server under sshd + +To run `rpki-rtr server` under `sshd`, you need to: + + 1. Decide whether to run a new instance of sshd on a separate port or use the standard port. `rpki-rtr` doesn't care, but some people seem to think that it's somehow more secure to run this service on a different port. Setting up `sshd` in general is beyond the scope of this documention, but most likely you can copy the bulk of your configuration from the standard config. + 2. Configure `sshd` to know about the `rpki-rtr` subsystem. Add something like this to your `sshd.conf`: + + Subsystem rpki-rtr /usr/local/bin/rpki-rtr + + 3. Configure the userid(s) you expect SSH clients to use to connect to the server. For operational use you almost certainly do _NOT_ want this user to have a normal shell, instead you should configure its shell to be the server (`/usr/local/bin/rpki-rtr` or wherever you've installed it on your system) and its home directory to be the `rpki-rtr` data directory (`/var/rcynic/rpki-rtr` or whatever you're using). If you're using passwords to authenticate instead of ssh keys (not recommended) you will always need to set the password(s) here when configuring the userid(s). + 4. Configure the `.ssh/authorized_keys` file for your clients; if you're using the example values given above, this would be `/var/rcynic/rpki-rtr/.ssh/authorized_keys`. You can have multiple SSH clients using different keys all logging in as the same SSH user, you just have to list all of the SSH keys here. You may want to consider using a `command=` parameter in the key line (see the `sshd(8)` man page) to lock down the SSH keys listed here so that they can only be used to run the `rpki-rtr` service. + +> If you're running a separate `sshd` for this purpose, you might also want to +add an `!AuthorizedKeysFile` entry pointing at this `authorized_keys` file so +that the server will only use this `authorized_keys` file regardless of what +other user accounts might exist on the machine: + + AuthorizedKeysFile /var/rcynic/rpki-rtr/.ssh/authorized_keys + +> There's a sample `sshd.conf` in the source directory. You will have to +modify it to suit your environment. The most important part is the `Subsystem` +line, which runs the `server.sh` script as the "`rpki-rtr`" service, as +required by the protocol specification. + +### Running rpki-rtr listener + +`rpki-rtr listener` is a free-standing plain TCP server which just listens on +a TCP socket then forks a child process running `rpki-rtr server`. + +All of the [caveats regarding plain TCP][rpki-rtr] apply to `rpki-rtr listener`. + +`rpki-rtr listener` takes one required argument, the TCP port number on which +to listen; it also accepts a second argument which specifies the rcynic output +directory, like `rpki-rtr server`. + + /usr/local/bin/rpki-rtr listener 42420 /var/rcynic/rpki-rtr + +### Other transports + +You can also run this code under `xinetd`, or the netpipes "`faucet`" program, +or `stunnel`...other than a few lines that might need hacking to log the +connection peer properly, the program really doesn't care. + +You _should_, however, care whether the channel you have chosen is secure; it +doesn't make a lot of sense to go to all the trouble of checking RPKI data +then let the bad guys feed bad data into your routers anyway because you were +running the rpki-rtr link over an unsecured TCP connection. + +## Other commands + +`rpki-rtr` has two other commands which might be useful for debugging: + + 1. `rpki-rtr client` implements a dumb client program for this protocol, over SSH, raw TCP, or by invoking `rpki-rtr server` directly in a subprocess. The output is not expected to be useful except for debugging. Either run it locally where you run the cron job, or run it anywhere on the net, as in + + $ rpki-rtr client tcp <hostname> <port> + + 2. `rpki-rtr show` will display a text dump of pre-digested data files in the current directory. + +[RFC-6810]: http://www.rfc-editor.org/rfc/rfc6810.txt +[rcynic]: 06.RPKI.RP.rcynic.md +[rpki-rtr]: 07.RPKI.RP.rpki-rtr.md |