sslutil: allow fingerprints to be specified in [hostsecurity] We introduce the [hostsecurity] config section. It holds per-host security settings. Currently, the section only contains a "fingerprints" option, which behaves like [hostfingerprints] but supports specifying the hashing algorithm. There is still some follow-up work, such as changing some error messages.

debuginstall: expose modulepolicy With this, you can check for pure easily: $ HGMODULEPOLICY=py ./hg debuginstall -T "{hgmodulepolicy}" py

revset: define table of sort() key functions This should be more readable than big "if" branch.

revset: factor out reverse flag of sort() key Prepares for making a table of sort keys. This assumes 'k' has at least one character, which should be guaranteed by keys.split().

tests: don't save host fingerprints in hgrc Previously, the test saved the host fingerprints in hgrc. Many tests override the fingerprint at run-time. This was a bit dangerous and was too magical for my liking. It will also interfere with a future patch that adds a new source for obtaining fingerprints. So change the test to require the fingerprint on every command invocation.

sslutil: calculate host fingerprints from additional algorithms Currently, we only support defining host fingerprints with SHA-1. A future patch will introduce support for defining fingerprints using other hashing algorithms. In preparation for that, we rewrite the fingerprint verification code to support multiple fingerprints, namely SHA-256 and SHA-512 fingerprints. We still only display the SHA-1 fingerprint. We'll have to revisit this code once we support defining fingerprints with other hash functions. As part of this, I snuck in a change to use range() instead of xrange() because xrange() isn't necessary for such small values.

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.

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.

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.

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.