view tests/test-duplicateoptions.py @ 31290:f819aa9dbbf9

sslutil: issue warning when [hostfingerprint] is used

Mercurial 3.9 added the [hostsecurity] section, which is better
than [hostfingerprints] in every way.

One of the ways that [hostsecurity] is better is that it supports
SHA-256 and SHA-512 fingerprints, not just SHA-1 fingerprints.

The world is moving away from SHA-1 because it is borderline
secure. Mercurial should be part of that movement.

This patch adds a warning when a valid SHA-1 fingerprint from
the [hostfingerprints] section is being used. The warning informs
users to switch to [hostsecurity]. It even prints the config
option they should set. It uses the SHA-256 fingerprint because
recommending a SHA-1 fingerprint in 2017 would be ill-advised.

The warning will print itself on every connection to a server until
it is fixed. There is no way to suppress the warning. I admit this
is annoying. But given the security implications of sticking with
SHA-1, I think this is justified. If this patch is accepted,
I'll likely send a follow-up to start warning on SHA-1
certificates in [hostsecurity] as well. Then sometime down
the road, we can drop support for SHA-1 fingerprints.

Credit for this idea comes from timeless in issue 5466.

from __future__ import absolute_import, print_function
import os
from mercurial import (
    commands,
    extensions,
    ui as uimod,
)

ignore = set(['highlight', 'win32text', 'factotum'])

if os.name != 'nt':
    ignore.add('win32mbcs')

disabled = [ext for ext in extensions.disabled().keys() if ext not in ignore]

hgrc = open(os.environ["HGRCPATH"], 'w')
hgrc.write('[extensions]\n')

for ext in disabled:
    hgrc.write(ext + '=\n')

hgrc.close()

u = uimod.ui.load()
extensions.loadall(u)

globalshort = set()
globallong = set()
for option in commands.globalopts:
    option[0] and globalshort.add(option[0])
    option[1] and globallong.add(option[1])

for cmd, entry in commands.table.iteritems():
    seenshort = globalshort.copy()
    seenlong = globallong.copy()
    for option in entry[1]:
        if (option[0] and option[0] in seenshort) or \
           (option[1] and option[1] in seenlong):
            print("command '" + cmd + "' has duplicate option " + str(option))
        seenshort.add(option[0])
        seenlong.add(option[1])