Gregory Szorc <gregory.szorc@gmail.com> [Sat, 28 May 2016 12:57:28 -0700] rev 29261
util: add sha256
Upcoming patches will teach host fingerprint checking to verify
non-SHA1 fingerprints.
Many x509 certificates these days are SHA-256. And modern browsers
often display the SHA-256 fingerprint for certificates. Since
SHA-256 fingerprints are highly visible and easy to obtain, we
want to support them for fingerprint pinning. So add SHA-256
support to util.
I did not add SHA-256 to DIGESTS and DIGESTS_BY_STRENGTH because
this will advertise the algorithm on the wire protocol. I wasn't
sure if that would be appropriate. I'm playing it safe by leaving
it out for now.
Gregory Szorc <gregory.szorc@gmail.com> [Sat, 28 May 2016 12:53:33 -0700] rev 29260
sslutil: move CA file processing into _hostsettings()
The CA file processing code has been moved from _determinecertoptions
into _hostsettings(). As part of the move, the logic has been changed
slightly and the "cacerts" variable has been renamed to "cafile" to
match the argument used by SSLContext.load_verify_locations().
Since _determinecertoptions() no longer contains any meaningful
code, it has been removed.
Gregory Szorc <gregory.szorc@gmail.com> [Sat, 28 May 2016 11:41:21 -0700] rev 29259
sslutil: move SSLContext.verify_mode value into _hostsettings
_determinecertoptions() and _hostsettings() are redundant with each
other. _hostsettings() is used the flexible API we want.
We start the process of removing _determinecertoptions() by moving
some of the logic for the verify_mode value into _hostsettings().
As part of this, _determinecertoptions() now takes a settings dict
as its argument. This is technically API incompatible. But since
_determinecertoptions() came into existence a few days ago as part
of this release, I'm not flagging it as such.
Gregory Szorc <gregory.szorc@gmail.com> [Sat, 28 May 2016 11:12:02 -0700] rev 29258
sslutil: introduce a function for determining host-specific settings
This patch marks the beginning of a series that introduces a new,
more configurable, per-host security settings mechanism. Currently,
we have global settings (like web.cacerts and the --insecure argument).
We also have per-host settings via [hostfingerprints].
Global security settings are good for defaults, but they don't
provide the amount of control often wanted. For example, an
organization may want to require a particular CA is used for a
particular hostname.
[hostfingerprints] is nice. But it currently assumes SHA-1.
Furthermore, there is no obvious place to put additional per-host
settings.
Subsequent patches will be introducing new mechanisms for defining
security settings, some on a per-host basis. This commits starts
the transition to that world by introducing the _hostsettings
function. It takes a ui and hostname and returns a dict of security
settings. Currently, it limits itself to returning host fingerprint
info.
We foreshadow the future support of non-SHA1 hashing algorithms
for verifying the host fingerprint by making the "certfingerprints"
key a list of tuples instead of a list of hashes.
We add this dict to the hgstate property on the socket and use it
during socket validation for checking fingerprints. There should be
no change in behavior.