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.\" Copyright (c) 2022 Stefan Sperling <stsp@openbsd.org>
.\"
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.Dd $Mdocdate$
.Dt GOTD.CONF 5
.Os
.Sh NAME
.Nm gotd.conf
.Nd gotd configuration file
.Sh DESCRIPTION
.Nm
is the run-time configuration file for
.Xr gotd 8 .
.Pp
The file format is line-based, with one configuration directive per line.
Any lines beginning with a
.Sq #
are treated as comments and ignored.
.Sh GLOBAL CONFIGURATION
The available global configuration directives are as follows:
.Bl -tag -width Ds
.It Ic connection Ar option
Set the specified options and limits for connections to the
.Xr gotd 8
unix socket.
.Pp
The
.Ic connection
directive may be specified multiple times, and multiple
.Ar option
arguments may be specified within curly braces:
.Pp
.Ic connection Brq Ar ...
.Pp
Each option should only be specified once.
If a given option is listed multiple times, the last line which sets this
option wins.
.Pp
Valid connection options are:
.Bl -tag -width Ds
.It Ic request timeout Ar seconds
Specify the inactivity timeout for operations between client and server.
If this timeout is exceeded while a Git protocol request is being processed,
the request will be aborted and the connection will be terminated.
.Pp
The timeout value may also have a suffix indicating its unit of measure.
Supported suffixes are:
.Pp
.Bl -tag -compact -width tenletters
.It Ar s No or Ar S
seconds
.It Ar m No or Ar M
minutes
.It Ar h No or Ar H
hours
.El
.Pp
The default timeout is 1h (3600 seconds, one hour).
This should only be changed if legitimate requests are exceeding the default
timeout for some reason, such as the server spending an extraordinary
amount of time generating a pack file.
.It Ic limit Ic user Ar identity Ar number
Limit the maximum amount of concurrent connections by the user with
the username
.Ar identity
to
.Ar number .
Numeric user IDs are also accepted.
.Pp
The default per-user limit is 4.
This should only be changed if concurrent connections from a given user are
expected to exceed the default limit, for example if an anonymous user
is granted read access and many concurrent connections will share this
anonymous user identity.
.El
.It Ic listen on Ar path
Set the path to the unix socket which
.Xr gotd 8
should listen on.
If not specified, the path
.Pa /var/run/gotd.sock
will be used.
.It Ic user Ar user
Set the
.Ar user
which will run
.Xr gotd 8 .
Initially,
.Xr gotd 8
requires root privileges in order to create its unix socket.
Afterwards,
.Xr gotd 8
drops privileges to the specified
.Ar user .
If not specified, the user _gotd will be used.
.El
.Sh REPOSITORY CONFIGURATION
At least one repository context must exist for
.Xr gotd 8
to function.
For each repository, access rules must be configured using the
.Ic permit
and
.Ic deny
configuration directives.
Multiple access rules can be specified, and the last matching rule
determines the action taken.
If no rule matches, access to the repository is denied.
.Pp
A repository context is declared with a unique
.Ar name ,
followed by repository-specific configuration directives inside curly braces:
.Pp
.Ic repository Ar name Brq ...
.Pp
.Xr got 1
and
.Xr git 1
clients can connect to a repository by including the repository's unique
.Ar name
in the request URL.
Clients appending the string
.Dq .git
to the
.Ar name
will also be accepted.
.Pp
If desired, the
.Ar name
may contain path-separators,
.Dq / ,
to expose repositories as part of a virtual client-visible directory hierarchy.
.Pp
The available repository configuration directives are as follows:
.Bl -tag -width Ds
.It Ic deny Ar identity
Deny repository access to users with the username
.Ar identity .
Group names may be matched by prepending a colon
.Pq Sq \&:
to
.Ar identity .
Numeric IDs are also accepted.
.It Ic path Ar path
Set the path to the Git repository.
Must be specified.
.It Ic permit Ar mode Ar identity
Permit repository access to users with the username
.Ar identity .
The
.Ar mode
argument must be set to either
.Ic ro
for read-only access,
or
.Ic rw
for read-write access.
Group names may be matched by prepending a colon
.Pq Sq \&:
to
.Ar identity .
Numeric IDs are also accepted.
.It Ic protect Brq Ar ...
The
.Cm protect
directive may be used to protect branches and tags in a repository
from being overwritten by potentially destructive client-side commands,
such as when
.Cm got send -f
and
.Cm git push -f
are used to change the history of a branch.
.Pp
To build a set of protected branches and tags, multiple
.Ic protect
directives may be specified per repository and
multiple
.Ic protect
directive parameters may be specified within curly braces.
.Pp
The available
.Cm protect
parameters are as follows:
.Pp
.Bl -tag -width Ds
.It Ic branch Ar name
Protect the named branch.
The branch may be created if it does not exist yet.
Attempts to delete the branch or change its history will be denied.
.Pp
If the
.Ar name
does not already begin with
.Dq refs/heads/
it will be looked up in the
.Dq refs/heads/
reference namespace.
.It Ic branch Ic namespace Ar namespace
Protect the given reference namespace, assuming that references in
this namespace represent branches.
New branches may be created in the namespace.
Attempts to change the history of branches or delete them will be denied.
.Pp
The
.Ar namespace
argument must be absolute, starting with
.Dq refs/ .
.It Ic tag Ic namespace Ar namespace
Protect the given reference namespace, assuming that references in
this namespace represent tags.
New tags may be created in the namespace.
Attempts to change or delete existing tags will be denied.
.Pp
The 
.Ar namespace
argument must be absolute, starting with
.Dq refs/ .
.El
.Pp
The special reference namespaces
.Dq refs/got/
and
.Dq refs/remotes/
do not need to be listed in
.Nm .
These namespaces are always protected and even attempts to create new
references in these namespaces will always be denied.
.El
.Sh FILES
.Bl -tag -width Ds -compact
.It Pa /etc/gotd.conf
Location of the
.Nm
configuration file.
.El
.Sh EXAMPLES
.Bd -literal -offset indent
# Run as the default user:
user _gotd

# Listen on the default socket:
listen on "/var/run/gotd.sock"

# This repository can be accessed via ssh://user@example.com/src
repository "src" {
	path "/var/git/src.git"
	permit rw flan_hacker
	permit rw :developers
	permit ro anonymous

	protect branch "main"
	protect tag namespace "refs/tags/"
}

# This repository can be accessed via
# ssh://user@example.com/openbsd/ports
repository "openbsd/ports" {
	path "/var/git/ports.git"
	permit rw :porters
	permit ro anonymous
	deny flan_hacker

	protect {
		branch "main"
		tag namespace "refs/tags/"
	}
}

# Use a larger request timeout value:
connection request timeout 2h

# Some users are granted a higher concurrent connection limit:
connection {
	limit user flan_hacker 16
	limit user anonymous 32
}
.Ed
.Sh SEE ALSO
.Xr got 1 ,
.Xr gotsh 1 ,
.Xr gotd 8