[[!template id=plugin name=graphviz author="[[JoshTriplett]]"]]
[[!tag type/chrome type/format]]

This plugin provides the [[ikiwiki/directive/graph]] [[ikiwiki/directive]].
This directive allows embedding [graphviz](http://www.graphviz.org/) graphs in a
page.

Security implications: graphviz does not seem to have any syntax exploitable to
perform file access or shell commands on the server.  However, the graphviz
plugin does make denial of service attacks somewhat easier: any user with edit
privileges can use this plugin to create large files without the need to send
large amounts of data, allowing them to more quickly fill the disk, run the
server out of memory, or use up large amounts of bandwidth.  Any user can
already do these things with just the core of ikiwiki, but the graphviz plugin
allows for an amplification attack, since users can send less data to use large
amounts of processing time and disk usage.

[[!if test="enabled(graphviz)" then="""
Some example graphs:

[[!graph src="a -> b -> c; a -> b;"]]
[[!graph src="a -- b -- c -- a;" prog="circo" type="graph"]]
"""]]

This plugin uses the [[!cpan Digest::SHA1]] perl module.