diff mercurial/sslutil.py @ 29289:3536673a25ae

sslutil: move and change warning when cert verification is disabled

A short time ago, validatesocket() didn't know the reasons why
cert verification was disabled. Multiple code paths could lead
to cert verification being disabled. e.g. --insecure and lack
of loaded CAs.

With the recent refactorings to sslutil.py, we now know the reasons
behind security settings. This means we can recognize when the user
requested security be disabled (as opposed to being unable to provide
certificate verification due to lack of CAs).

This patch moves the check for certificate verification being disabled
and changes the wording to distinguish it from other states. The
warning message is purposefully more dangerous sounding in order
to help discourage people from disabling security outright.

We may want to add a URL or hint to this message. I'm going to wait
until additional changes to security defaults before committing to
something.

--- a/mercurial/sslutil.py	Wed Jun 01 19:57:20 2016 -0700
+++ b/mercurial/sslutil.py	Mon May 30 13:15:53 2016 -0700
@@ -354,6 +354,18 @@
         raise error.Abort(_('%s certificate error: '
                            'no certificate received') % host)
 
+    if settings['disablecertverification']:
+        # We don't print the certificate fingerprint because it shouldn't
+        # be necessary: if the user requested certificate verification be
+        # disabled, they presumably already saw a message about the inability
+        # to verify the certificate and this message would have printed the
+        # fingerprint. So printing the fingerprint here adds little to no
+        # value.
+        ui.warn(_('warning: connection security to %s is disabled per current '
+                  'settings; communication is susceptible to eavesdropping '
+                  'and tampering\n') % host)
+        return
+
     # If a certificate fingerprint is pinned, use it and only it to
     # validate the remote cert.
     peerfingerprints = {
@@ -383,19 +395,6 @@
                  (host, nicefingerprint))
         return
 
-    # If insecure connections were explicitly requested, print a warning
-    # and do no verification.
-    #
-    # It may seem odd that this is checked *after* host fingerprint pinning.
-    # This is for backwards compatibility (for now). The message is also
-    # the same as below for BC.
-    if settings['disablecertverification']:
-        ui.warn(_('warning: %s certificate with fingerprint %s not '
-                  'verified (check %s or web.cacerts '
-                  'config setting)\n') %
-                (host, nicefingerprint, section))
-        return
-
     if not sock._hgstate['caloaded']:
         ui.warn(_('warning: %s certificate with fingerprint %s '
                   'not verified (check %s or web.cacerts config '