add some optional indirection to matching of principal names listed

in certificates. Currently, a certificate must include the a user's name
to be accepted for authentication. This change adds the ability to
specify a list of certificate principal names that are acceptable.

When authenticating using a CA trusted through ~/.ssh/authorized_keys,
this adds a new principals="name1[,name2,...]" key option.

For CAs listed through sshd_config's TrustedCAKeys option, a new config
option "AuthorizedPrincipalsFile" specifies a per-user file containing
the list of acceptable names.

If either option is absent, the current behaviour of requiring the
username to appear in principals continues to apply.

These options are useful for role accounts, disjoint account namespaces
and "user@realm"-style naming policies in certificates.

feedback and ok markus@

0 files changed, 0 insertions, 0 deletions