ssh: Update to OpenSSH 9.6p1

From the release notes,

> This release contains a number of security fixes, some small features
> and bugfixes.

The most significant change in 9.6p1 is a set of fixes for a newly-
discovered weakness in the SSH transport protocol. The fix was already
merged into FreeBSD and released as FreeBSD-SA-23:19.openssh.

Full release notes at https://www.openssh.com/txt/release-9.6

Relnotes: Yes
Sponsored by: The FreeBSD Foundation

ssh: Update to OpenSSH 9.4p1

Excerpts from the release notes:

* ssh-agent(1): PKCS#11 modules must now be specified by their full
paths. Previously dlopen(3) could search for them in system
library directories.

* ssh(1): allow forwarding Unix Domain sockets via ssh -W.

* ssh(1): add support for configuration tags to ssh(1).
This adds a ssh_config(5) "Tag" directive and corresponding
"Match tag" predicate that may be used to select blocks of
configuration similar to the pf.conf(5) keywords of the same
name.

* ssh(1): add a "match localnetwork" predicate. This allows matching
on the addresses of available network interfaces and may be used to
vary the effective client configuration based on network location.

* ssh-agent(1): improve isolation between loaded PKCS#11 modules
by running separate ssh-pkcs11-helpers for each loaded provider.

* ssh-agent(1), ssh(1): improve defences against invalid PKCS#11
modules being loaded by checking that the requested module
contains the required symbol before loading it.

* ssh(1): don't incorrectly disable hostname canonicalization when
CanonicalizeHostname=yes and ProxyJump was expicitly set to
"none". bz3567

Full release notes at https://www.openssh.com/txt/release-9.4

Relnotes: Yes
Sponsored by: The FreeBSD Foundation

Upgrade to OpenSSH 7.6p1. This will be followed shortly by 7.7p1.

This completely removes client-side support for the SSH 1 protocol,
which was already disabled in 12 but is still enabled in 11. For that
reason, we will not be able to merge 7.6p1 or newer back to 11.

Upgrade to OpenSSH 6.8p1.

Pull in all the OpenSSH bits that we'd previously left out because we
didn't use them. This will make future merges from the vendor tree much
easier.

Approved by: re (gjb)

Remove a bunch of files we don't need to build OpenSSH. They are still
available in base/vendor-crypto/openssh/dist/.

Properly flatten openssh/dist.

Vendor import of OpenSSH 4.4p1.

ssh: Update to OpenSSH 9.4p1

Excerpts from the release notes:

* ssh-agent(1): PKCS#11 modules must now be specified by their full
paths. Previously dlopen(3) could search for them in system
library directories.

* ssh(1): allow forwarding Unix Domain sockets via ssh -W.

* ssh(1): add support for configuration tags to ssh(1).
This adds a ssh_config(5) "Tag" directive and corresponding
"Match tag" predicate that may be used to select blocks of
configuration similar to the pf.conf(5) keywords of the same
name.

* ssh(1): add a "match localnetwork" predicate. This allows matching
on the addresses of available network interfaces and may be used to
vary the effective client configuration based on network location.

* ssh-agent(1): improve isolation between loaded PKCS#11 modules
by running separate ssh-pkcs11-helpers for each loaded provider.

* ssh-agent(1), ssh(1): improve defences against invalid PKCS#11
modules being loaded by checking that the requested module
contains the required symbol before loading it.

* ssh(1): don't incorrectly disable hostname canonicalization when
CanonicalizeHostname=yes and ProxyJump was expicitly set to
"none". bz3567

Full release notes at https://www.openssh.com/txt/release-9.4

Relnotes: Yes
Sponsored by: The FreeBSD Foundation

Upgrade to OpenSSH 7.6p1. This will be followed shortly by 7.7p1.

This completely removes client-side support for the SSH 1 protocol,
which was already disabled in 12 but is still enabled in 11. For that
reason, we will not be able to merge 7.6p1 or newer back to 11.

Upgrade to OpenSSH 6.8p1.

Pull in all the OpenSSH bits that we'd previously left out because we
didn't use them. This will make future merges from the vendor tree much
easier.

Approved by: re (gjb)

Remove a bunch of files we don't need to build OpenSSH. They are still
available in base/vendor-crypto/openssh/dist/.

Properly flatten openssh/dist.

Vendor import of OpenSSH 4.4p1.

Remove a bunch of files we don't need to build OpenSSH. They are still
available in base/vendor-crypto/openssh/dist/.

Vendor import of OpenSSH 4.4p1.