fix(nova_file_controller): prevent path traversal in static file routes#383
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Taure wants to merge 2 commits into
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fix(nova_file_controller): prevent path traversal in static file routes#383Taure wants to merge 2 commits into
Taure wants to merge 2 commits into
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User-supplied path segments were joined onto the served root without canonicalisation, so a request containing .. (or %2E%2E once decoded) could escape the served directory. The controller now decodes each segment, rejects absolute paths, and resolves . and .. against a zero-depth floor; any attempt to climb above the root returns 403. Also unblocks safe URL-decoding of segments, so UTF-8 filenames served from a wildcard route work as expected.
Adds 13 tests covering depth-counting edge cases (chained .., mixed subdir/.., long traversal chains, going below root after descending), common bypass attempts (double URL encoding, backslash, empty segment, '...', NUL byte), and previously-untested positive paths (subdirectory serve, '.' segments, .. that resolves back inside root).
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Fixes a path-traversal weakness in
nova_file_controller:get_dir/1: user-supplied URL segments were joined onto the served root without canonicalisation, so a request containing..(or%2E%2Eonce decoded) could escape the served directory.The controller now:
./..against a zero-depth floor; anything climbing above the root returns403.This also unblocks safe URL-decoding of segments, so UTF-8 filenames served from a wildcard route work as expected (which addresses the legitimate part of #381 — that PR can rebase on this and drop the hand-rolled decode in
get_dir, leaving only the mime /file_infofixes).Eight new EUnit tests cover:
..traversal -> 403.%2E%2Etraversal -> 403.%2e%2E-> 403.%2E%2E%2F...-> 403.Test plan
rebar3 eunit(390 tests, 0 failures)rebar3 dialyzer(clean)rebar3 xref(clean)~/bin/elp eqwalize nova_file_controller(no new errors)