[BA] Beyond File-Level Privacy: Advanced Functionality in End-to-End Encrypted Git Services

252 / BBB

2026-10-06

Luca Eckenfels

15:45

In modern software development, version control using Git has become indispensable.
Source code is typically hosted on centralized infrastructures where operators retain full
access to repositories and may act as malicious adversaries. Additionally, a server-side data
breach leads to the immediate compromise of the code. To protect against these attacks,
prior work guarantees both the confidentiality of file contents and repository integrity.
However, the protection of filenames and directory paths remains largely unaddressed. In
this thesis, we formalize a security notion for filename and path confidentiality and prove
that it is at least as strong as the data confidentiality guarantee while satisfying repository
unforgeability from Li et al. (CCS2025). Furthermore, we propose an extended Git service
that satisfies our security notion, formally prove its security, and demonstrate that the
service requires only 160 ms to update the ciphertext repository.