# NAME
**gmid** - dead simple zero configuration gemini server
# SYNOPSIS
**gmid**
\[**-fh**]
\[**-c** *cert.pem*]
\[**-d** *docs*]
\[**-k** *key.pem*]
\[**-p** *port*]
\[**-x** *cgi-bin*]
# DESCRIPTION
**gmid**
is a very simple and minimal gemini server that can serve static files
and execute CGI scripts.
**gmid**
will strip any sequence of
*../*
or trailing
*..*
in the requests made by clients and will refuse to follow symlinks.
Furthermore, on
OpenBSD,
pledge(2)
and
unveil(2)
are used to ensure that
**gmid**
dosen't do anything else than read files from the given directory,
accept network connections and, optionally, execute CGI scripts.
It should be noted that
**gmid**
is very simple in its implementation, and so it may not be appropriate
for serving sites with lots of users.
After all, the code is single threaded and use a single process,
although it can handle multiple clients at the same time.
If a user request path is a directory,
**gmid**
will try to serve a
*index.gmi*
file inside that directory.
The options are as follows:
**-c** *cert.pem*
> The certificate to use, by default is
> *cert.pem*.
**-d** *docs*
> The root directory to serve.
> **gmid**
> won't serve any file that is outside that directory.
> By default is
> *docs*.
**-f**
> stays and log in the foreground, do not daemonize the process.
**-h**
> Print the usage and exit.
**-k** *key.pem*
> The key for the certificate, by default is
> *key.pem*.
**-p** *port*
> The port to bind to, by default 1965.
**-x** *dir*
> Enable execution of CGI scripts inside the given directory (relative
> to the document root.) Cannot be provided more than once.
# CGI
When CGI scripts are enabled for a directory, a request for an
executable file will execute it and fed its output to the client.
The CGI scripts will inherit the environment from
**gmid**
with these additional variables set:
`SERVER_SOFTWARE`
> "gmid"
`SERVER_PORT`
> "1965"
`SCRIPT_NAME`
> The (public) path to the script.
`SCRIPT_EXECUTABLE`
> The full path to the executable.
`REQUEST_URI`
> The user request (without the query parameters.)
`REQUEST_RELATIVE`
> The request relative to the script.
`QUERY_STRING`
> The query parameters.
`REMOTE_HOST`
> The remote IP address.
`REMOTE_ADDR`
> The remote IP address.
`DOCUMENT_ROOT`
> The root directory being served, the one provided with the
> *d*
> parameter to
> **gmid**
`AUTH_TYPE`
> The string "Certificate" if the client used a certificate, otherwise unset.
`REMOTE_USER`
> The subject of the client certificate if provided, otherwise unset.
`TLS_CLIENT_ISSUER`
> The is the issuer of the client certificate if provided, otherwise unset.
`TLS_CLIENT_HASH`
> The hash of the client certificate if provided, otherwise unset.
> The format is "ALGO:HASH".
Let's say you have a script in
*/cgi-bin/script*
and the user request is
*/cgi-bin/script/foo/bar?quux*.
Then
`SCRIPT_NAME`
will be
*/cgi-bin/script*,
`SCRIPT_EXECUTABLE`
will be
*$DOCUMENT\_ROOT/cgi-bin/script*,
`REQUEST_URI`
will be
*/cgi-bin/script/foo/bar*,
`REQUEST_RELATIVE`
will be
*foo/bar and*
`QUERY_STRING`
will be
*quux*.
# EXAMPLES
To quickly getting started
$ # generate a cert and a key
$ openssl req -x509 -newkey rsa:4096 -keyout key.pem \
-out cert.pem -days 365 -nodes
$ mkdir docs
$ cat <<EOF > docs/index.gmi
# Hello world
test paragraph...
EOF
$ gmid -c cert.pem -k key.pem -d docs
Now you can visit gemini://localhost/ with your preferred gemini
client.
To add some CGI scripts, assuming a setup similar to the previous
example, you can
$ mkdir docs/cgi-bin
$ cat <<EOF > docs/cgi-bin/hello-world
#!/bin/sh
printf "20 text/plain\r\n"
echo "hello world!"
EOF
$ gmid -x cgi-bin
Note that the argument to the
**-x**
option is
*cgi-bin*
and not
*docs/cgi-bin*,
since it's relative to the document root.
# CAVEATS
* it doesn't support virtual hosts: the host part of the request URL is
completely ignored.
