We need a new feature bit for BOLT11 invoices in order to indicate that
they contain the new blinded path tagged field. Tagged fields pre-date
TLV and so nodes who dont understand them will simply skip them.
Therefore the feature bit helps them to fail fast.
This commit adds encoding and decoding for blinded route data blobs.
TLV fields such as path_id (which are only used for the final hop)
are omitted to minimize the change size.
We'll need to pack feature vectors for route blinding, so we pull
the encoding/decoding out into separate functions (currently
contained in ChannelType). Though it's more lines of code, we keep
most of the ChannelType assertions so that we strictly enforce
use of the alias.
In this commit, we carry out a new notion introduced during a recent
spec meeting to use a feature bit plus 100 before the feature has been
finalized in the spec.
We split into the Final and Staging bits.
Base 32 encoded bolt 11 invoices only allow 10 bits to express the
length of the feature vector in a tagged field, so there is a much
lower limit on the values invoice custom features can hold.
Other places in the protocol are theoretically limited by the maximum
message size, but since we express a feature bit as u16 we don't need
to be concerned about this.
The decision is made to track maximum per-set in the feature manager,
which is conceptually aware of sets and then validate in lnwire/features
against some arbitrary maximum value provided to the caller to keep
the base features package unaware of sets.
In this commit, we add awareness of the option_shutdown_anysegwit that
permits both sides to send newer segwit based addresses. This'll
eventually enable us to send taproot addresses for co-op close.
This defines the zero-conf feature bit, the scid-alias feature bit,
the zero-conf channel type, and the scid-alias channel type. It also
defines the dependency "tree" that exists for the feature bits.
The scid-alias feature bit signals that the node requires an alias
short channel id to be sent in funding_locked. The scid-alias channel
type requires that the channel is private, in addition to some other
forwarding-related privacy measures.
If these bits are present, then both sides can examine the new
CommitmentType TLV field that's present and use this in place of the
existing implicit commiment type negotiation. With this change, it's now
possible to actually deprecate old unsupported commitment types
properly.
In this commit, we add a new RequiresFeature method to the feature
vector struct. This method allows us to check if the set of features
we're examining *require* that the even portion of a bit pair be set.
This can be used to check if new behavior should be allowed (after we
flip new bits to be required) for existing contexts.
The number and the name will be separate on the rpc level, so we remove
the feature bit from the string. Currently this method is unused apart
from maybe in some rare logging instances.
This commit adds the feature bit and additional fields
required in `open_channel` and `accept_channel` wire
messages for `option_upfront_shutdown_script`.
This commit introduces a feature.Manager, which derives feature vectors
for various contexts within the daemon. The sets can be described via a
staticly compiled format, which makes any runtime adjustments to the
feature sets when the manager is initialized.
In this commit, we fix a bug in the way we defined our even/odd features
for a particular feature. The check for if a feature bit is part of a
pair assumes that the pair bit has the exact same name as the bit being
queried. The way we defined our feature map didn't take note of this
assumption, as a result, any attempts to require a new bit moving from
optional to required would fail since the bit would be found, but the
names differed.
This commit adds the required feature name to our
set of local known features. This will allow other
peers connecting to us to set the required gossip
queries feature bit. This is required for the
subsequent commits, which instruct the server to
set the bit depending on user configured preferences.
