control: allow to query for latest TRC

[lukedirtwalker]

Currently querying for the latest TRC was not allowed, because TRC ID validation would fail. However it should be completely fine to query for the latest TRC. This commit fixes it.

[jiceatscion]

This change is 

[oncilla]

Reviewable status: 0 of 1 files reviewed, 1 unresolved discussion (waiting on @jiceatscion and @lukedirtwalker)

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control/trust/grpc/proto.go line 70 at r1 (raw file):

	// If the query is for the latest version don't validate the ID fully, only
	// the ISD ID.
	if id.Base.IsLatest() && id.Serial.IsLatest() {

IMO it is also legit to ask for latest serial on a fixed base version.

[lukedirtwalker]

Reviewable status: 0 of 1 files reviewed, 1 unresolved discussion (waiting on @jiceatscion and @oncilla)

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control/trust/grpc/proto.go line 70 at r1 (raw file):

Previously, oncilla (Dominik Roos) wrote…

IMO it is also legit to ask for latest serial on a fixed base version.

The DB does not think so:

scion/private/storage/trust/sqlite/db.go

Lines 84 to 86 in 4c929f6

	if id.Base.IsLatest() != id.Serial.IsLatest() {
	return cppki.SignedTRC{}, serrors.New("unsupported TRC ID for query", "id", id)
	}

[oncilla]

Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @jiceatscion)

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control/trust/grpc/proto.go line 70 at r1 (raw file):

Previously, lukedirtwalker (Lukas Vogel) wrote…

The DB does not think so:

scion/private/storage/trust/sqlite/db.go

Lines 84 to 86 in 4c929f6

	if id.Base.IsLatest() != id.Serial.IsLatest() {
	return cppki.SignedTRC{}, serrors.New("unsupported TRC ID for query", "id", id)
	}

Fine. Overruled by our past selves

[jiceatscion]

Reviewed all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @lukedirtwalker)