When i'm trying to understand a message signature, i care that i know
who it came from (the "validity" of the identity associated with the
key), *not* whether i'm willing to accept the keyholder's other
identity assertions (the "trust" associated with the certificate).
We've been reporting User ID information based on the "trust"
associated with the certificate, because GMime didn't clearly expose
the validity of the User IDs.
This change relies on fixes made in GMime 3.0.3 and later which
include https://github.com/jstedfast/gmime/pull/18.
The problem shows up on 32 bit architectures where sizeof(time_t) !=
sizeof(gint64). Upcasting the 32 bit time_t to a 64 bit integer
should hopefully be safe.
The "key_id" field seems to used for userid in gmime-3.0, while the
keyid is dropped in the fingerprint field if the full fingerprint is
not available.
It turns out that our use of GMimeStreamPipe has only succeeded
because gmime has been ignoring some seek failures; this will no
longer be the case in gmime 3.0, so we use a GMimeStreamPipe, which
does not assume seekability, wrapped in a buffering stream.
