| 2022-02-14 | git-authenticate: Ensure the target is a descendant of the introductory commit....Fixes a bug whereby authentication of a commit *not* descending from the
introductory commit could succeed, provided the commit verifies the
authorization invariant.
In the example below, A is a common ancestor of the introductory commit
I and of commit X. Authentication of X would succeed, even though it is
not a descendant of I, as long as X is authorized according to the
'.guix-authorizations' in A:
X I
\ /
A
This is because, 'authenticate-repository' would not check whether X
descends from I, and the call (commit-difference X I) would return X.
In practice that only affects forks because it means that ancestors of
the introductory commit already contain a '.guix-authorizations' file.
* guix/git-authenticate.scm (authenticate-repository): Add call to
'commit-descendant?'.
* tests/channels.scm ("authenticate-channel, not a descendant of introductory commit"):
New test.
* tests/git-authenticate.scm ("authenticate-repository, target not a descendant of intro"):
New test.
* tests/guix-git-authenticate.sh: Expect earlier test to fail since
9549f0283a78fe36f2d4ff2a04ef8ad6b0c02604 is not a descendant of
$intro_commit. Add new test targeting an ancestor of the introductory
commit, and another test targeting the v1.2.0 commit.
* doc/guix.texi (Specifying Channel Authorizations): Add a sentence.
| Ludovic Courtès |