sslutil: print a warning when using TLS 1.0 on legacy Python
Mercurial now requires TLS 1.1+ when TLS 1.1+ is supported by the
client. Since we made the decision to require TLS 1.1+ when running
with modern Python versions, it makes sense to do something for
legacy Python versions that only support TLS 1.0.
Feature parity would be to prevent TLS 1.0 connections out of the
box and require a config option to enable them. However, this is
extremely user hostile since Mercurial wouldn't talk to https://
by default in these installations! I can easily see how someone
would do something foolish like use "--insecure" instead - and
that would be worse than allowing TLS 1.0!
This patch takes the compromise position of printing a warning when
performing TLS 1.0 connections when running on old Python
versions. While this warning is no more annoying than the
CA certificate / fingerprint warnings in Mercurial 3.8, we provide
a config option to disable the warning because to many people
upgrading Python to make the warning go away is not an available
recourse (unlike pinning fingerprints is for the CA warning).
The warning appears as optional output in a lot of tests.
Source bundle was generated with the following script:
# hg init
# echo a > a
# ln -s a l
# hg ci -Ama -d'0 0'
# mkdir b
# echo a > b/a
# chmod +x b/a
# hg ci -Amb -d'1 0'
$ hg init
$ hg -q pull "$TESTDIR/bundles/test-manifest.hg"
The next call is expected to return nothing:
$ hg manifest
$ hg co
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg manifest
a
b/a
l
$ hg files -vr .
2 a
2 x b/a (glob)
1 l l
$ hg files -r . -X b
a
l
$ hg manifest -v
644 a
755 * b/a
644 @ l
$ hg manifest --debug
b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 644 a
b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 755 * b/a
047b75c6d7a3ef6a2243bd0e99f94f6ea6683597 644 @ l
$ hg manifest -r 0
a
l
$ hg manifest -r 1
a
b/a
l
$ hg manifest -r tip
a
b/a
l
$ hg manifest tip
a
b/a
l
$ hg manifest --all
a
b/a
l
The next two calls are expected to abort:
$ hg manifest -r 2
abort: unknown revision '2'!
[255]
$ hg manifest -r tip tip
abort: please specify just one revision
[255]