qgis - Is there an open source tool to planarize graphs?

I read about the planarize function in ArcGIS, which seem to do exactly what I want. Is there a similar feature in QGIS or another free tool?

I have a shapefile with various shapes intersecting each other and I want each intersection to become a node and between every two nodes to have a simple line.

The goal is to easily convert my .shp in .osm and use it with Graphserver. As it is, Graphserver says I don't have edges, and I deduced the above is my problem.

Thanks a lot