Automated software license analysis

摘要

Software license is a legal instrument governing the usage or redistribution of copyright-protected software. License analysis is an elaborate undertaking, especially in case of large software consisting of numerous modules under different licenses. This paper describes an automated approach for supporting software license analysis. The approach is implemented in a reverse engineering tool called ASLA. We provide a detailed description of the architecture and features of the tool. The tool is evaluated on the basis of an analysis of 12 OSS (open source software) packages. The results show that licenses for (on average) 89% of the source code files can be identified by using ASLA and that the efficiency of the automated analysis is (on average) 111 files per second. In a further comparison with two other open source license analyzers—OSLC and FOSSology—ASLA shows a competitive performance. The results validate the general feasibility of the ASLA approach in the context of analyzing non-trivial OSS packages.