1 # gmid
2 
3 gmid is a full-featured Gemini server written with security in mind.
4 It can serve static files, has optional FastCGI and proxying support,
5 and a rich configuration syntax.
6 
7 A few helper programs are shipped as part of gmid:
8 
9  - `gg` is a simple command-line Gemini client.
10 
11  - `gemexp` is a stripped-down config-less version of gmid to quickly
12    serve a directory from the command line.
13 
14  - `titan` is a command-line titan client.
15 
16 
17 ## Internationalisation (IRIs, UNICODE, punycode, all that stuff)
18 
19 Even thought the current Gemini specification doesn't mention anything
20 in this regard, I do think these are important things and so I tried
21 to implement them in the most user-friendly way I could think of.
22 
23 For starters, gmid has full support for IRI (RFC3987 —
24 Internationalized Resource Identifiers).  IRIs are a superset of URIs,
25 so there aren't incompatibilities with URI-only clients.
26 
27 There is full support also for punycode.  In theory, the user doesn't
28 even need to know that punycode is a thing.  The hostname in the
29 configuration file can (and must be) in the decoded form (e.g. `naïve`
30 and not `xn--nave-6pa`), gmid will do the rest.
31 
32 The only missing piece is UNICODE normalisation of the IRI path: gmid
33 doesn't do that (yet).
34 
35 
36 ## Configuration
37 
38 [httpd]: https://man.openbsd.org/httpd.8
39 
40 gmid has a rich configuration file, heavily inspired by OpenBSD'
41 [httpd(8)][httpd], with every detail carefully documented in the
42 manpage.  Here's a minimal example of a config file:
43 
44 ```conf
45 server "example.com" {
46 	listen on * port 1965
47 	cert "/path/to/cert.pem"
48 	key  "/path/to/key.pem"
49 	root "/var/gemini/example.com"
50 }
51 ```
52 
53 and a slightly more complex one
54 
55 ```conf
56 cert_root = "/path/to/keys"
57 
58 server "example.com" {
59 	listen on * port 1965
60 
61 	alias "foobar.com"
62 
63 	cert $cert_root "/example.com.crt"
64 	key  $cert_root "/example.com.pem"
65 	root "/var/gemini/example.com"
66 
67 	# lang for text/gemini files
68 	lang "en"
69 
70 	# only for locations that matches /files/*
71 	location "/files/*" {
72 		# generate directory listings
73 		auto index on
74 	}
75 
76 	location "/repo/*" {
77 		# change the index file name
78 		index "README.gmi"
79 		lang "it"
80 	}
81 }
82 ```
83 
84 
85 ## Building
86 
87 gmid depends on libevent2, LibreSSL or OpenSSL, and yacc or GNU bison.
88 
89 The build is as simple as
90 
91 	$ ./configure
92 	$ make
93 
94 If the configure scripts fails to pick up something, please open an
95 issue or notify me via email.
96 
97 To install execute:
98 
99 	# make install
100 
101 Please keep in mind that the master branch, from time to time, may be
102 accidentally broken on some platforms.  gmid is developed primarily on
103 OpenBSD/amd64 and commits on the master branch don't get always tested
104 in other OSes.  Before tagging a release however, a comprehensive
105 testing on various platform is done to ensure that everything is
106 working as intended.
107 
108 
109 ### Testing
110 
111 Execute
112 
113 	$ make regress
114 
115 to start the suite.  Keep in mind that the regression tests needs to
116 create a few file inside the `regress` directory and bind the 10965
117 port.
118 
119 
120 ## Contributing
121 
122 Any form of contribution is welcome, not only patches or bug reports.
123 If you have a sample configuration for some specific use-case, a
124 script or anything that could be useful to others, consider adding it
125 to the `contrib` directory.
126 
127 
128 ## Architecture/Security considerations
129 
130 The internal architecture was revisited for the 2.0 release.  For
131 earlier releases, please refer to previous revision of this file.
132 
133 gmid has a privsep design, where the operations done by the daemon are
134 splitted into multiple processes:
135 
136  - main: the main process is the only one that keeps the original
137    privileges.  It opens the TLS certificates on the behalf of the
138    `server` and `crypto` processes, reloads the configuration upon
139    `SIGHUP` and re-opens the log files upon `SIGUSR1`.
140 
141  - logger: handles the logging with syslog and/or local files.
142 
143  - server: listens for connections and serves the request.  It also
144    speaks FastCGI and do the proxying.
145 
146  - crypto: holds the TLS private keys to avoid a compromised `server`
147    process to disclose them.