Attempt to clarify what the SHAttered attack means in practice for
Git. The previous version of the text made no mention whatsoever of
Git already having a mitigation for this specific attack, which the
SHAttered researchers claim will detect cryptanalytic collision
attacks.
I may have gotten some of the nuances wrong, but as far as I know this
new text accurately summarizes the current situation with SHA-1 in
git. I.e. git doesn't really use SHA-1 anymore, it uses
Hardened-SHA-1 (they just so happen to produce the same outputs
99.99999999999...% of the time).
Thus the previous text was incorrect in asserting that:
[...]As a result [of SHAttered], SHA-1 cannot be considered
cryptographically secure any more[...]
That's not the case. We have a mitigation against SHAttered, *however*
we consider it prudent to move to work towards a NewHash should future
vulnerabilities in either SHA-1 or Hardened-SHA-1 emerge.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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| .. | ||
| .gitignore | ||
| api-allocation-growing.txt | ||
| api-argv-array.txt | ||
| api-config.txt | ||
| api-credentials.txt | ||
| api-diff.txt | ||
| api-directory-listing.txt | ||
| api-error-handling.txt | ||
| api-gitattributes.txt | ||
| api-grep.txt | ||
| api-history-graph.txt | ||
| api-index-skel.txt | ||
| api-index.sh | ||
| api-merge.txt | ||
| api-object-access.txt | ||
| api-oid-array.txt | ||
| api-parse-options.txt | ||
| api-quote.txt | ||
| api-ref-iteration.txt | ||
| api-remote.txt | ||
| api-revision-walking.txt | ||
| api-run-command.txt | ||
| api-setup.txt | ||
| api-sigchain.txt | ||
| api-submodule-config.txt | ||
| api-trace.txt | ||
| api-tree-walking.txt | ||
| api-xdiff-interface.txt | ||
| bitmap-format.txt | ||
| hash-function-transition.txt | ||
| http-protocol.txt | ||
| index-format.txt | ||
| long-running-process-protocol.txt | ||
| pack-format.txt | ||
| pack-heuristics.txt | ||
| pack-protocol.txt | ||
| partial-clone.txt | ||
| protocol-capabilities.txt | ||
| protocol-common.txt | ||
| racy-git.txt | ||
| repository-version.txt | ||
| send-pack-pipeline.txt | ||
| shallow.txt | ||
| signature-format.txt | ||
| trivial-merge.txt | ||