As we now require `rustfmt` pass on a subset of our files, its
helpful to have a script which will automatically format any
required files so that contributors don't need to think too hard
about it.
`ChannelId` is just a 32-byte array, so there's not a lot of value
in passing it by reference to `funding_transaction_generated`,
which we fix here.
This is also nice for bindings as languages like Java can better
analyze whether the `ChannelManager` ends up with a reference to
the `ChannelId`.
Now that `ChannelManager::send_payment_with_route` is deprecated,
we don't care too much about making it as effecient as possible, so
there's not much cost to making it take `Route` by value. This
avoids bindings being unsure if the by-reference `Route` passed
needs to outlive the `ChannelManager` itself or if it only needs to
outlive the method call, creating some call overhead by forcing a
`Route::clone`, but avoiding a memory leak.
We probably should have done this long ago a release or two after
adding `send_payment`, but we didn't and the second best time is
now.
`send_payment_with_route` has particularly hard to use retry
semantics that make it unsuitable for real use. Once we get the
last of our users off of it, we'll want to remove it (or at least
mark it test-only), but we should start by deprecating it.
The recently released `tokio` 1.39 bumped their MSRV to rustc 1.70.
Here, we pin the `tokio` version to 1.38 for users that require to
maintain our MSRV of rustc 1.63.
Now that ChannelManager uses a known OffersContext when creating blinded
paths, OffersContext::Unknown is no longer needed. Remove it and update
OffersMessageHandler to us an Option, which is more idiomatic for
signifying whether a message was delivered with or without an
OffersContext.
Instead of using OffersContext::Unknown for the Bolt12Invoice reply path
use OffersContext::InboundPayment to include the payment hash.
OffersContext::Unknown will be removed in another commit.
When creating a Bolt12Invoice in fuzz tests, use
BlindedPath::new_for_payment instead of BlindedPath::new_for_message.
This way PaymentContext is used instead of MessageContext, as is more
realistic though should not affect the test. This allows us to remove
OffersContext::Unknown.
Best practice is to use different IV bytes for different contexts.
Update Offer and Refund metadata computation to use different IV bytes
when the metadata is included in a blinded path. For invoice requests,
the metatdata will always be in the blinded path, so it remains the
same.
In an upcoming commit, the iv_bytes used in MetadataMaterial will vary
depending on when whether a blinded path is included in the
corresponding message. Delay adding into MetadataMaterial::hmac as
otherwise the HmacEngine would need to be re-initialized using an
ExpandedKey, which won't be readily available.
8403755a2a introduced a separate path
for funding a channel without a full funding transaction, relying
on users to manually broadcast the funding tx. One of the major
things that makes this path less safe is that for other paths we're
supposed to validate that all inputs have witnesses, making the
funding transaction (likely) txid-non-malleable.
However, in one of several rewrites of that commit the funding tx
tests ended up getting elided in some call paths, which is fixed
here.
InvoiceRequest and Refund have payer_metadata which consists of an
encrypted payment id and a nonce used to derive its signing keys and
authenticate any corresponding invoices. Now that the blinded paths
include this data in their OffersContext, remove the nonce as it is now
redundant. Keep the encrypted payment id as some data is needed in the
payer metadata according to the spec. This saves space and prevents
de-anonymization attacks as along as the nonce isn't revealed.
When authenticating that an invoice is for a valid invoice request, the
payer metadata is needed. Some of this data will be removed in the next
commit and instead be included in the message context of the request's
reply path. Add this data to Event::InvoiceReceived so that asynchronous
invoice handling can verify properly.
When a Bolt12Invoice is handled with an OfferContext, use both the
containing payment_id and nonce to verify that it is for a pending
outbound payment. Previously, the nonce the payment_id were taken from
the payer_metadata and the latter was compared against the payment_id
in the OfferContext. The payer_metadata thus no longer needs to include
either when a blinded path is used. However, some payer_metadata will
still be needed as per the spec.
To authenticate that a Bolt12Invoice is for a valid InvoiceRequest or
Refund, include the nonce from the payer_metadata in the InvoiceRequest
reply path or Refund::paths, respectively. This can be used to prevent
de-anonymization attacks where an attacker sends invoices using
self-constructed paths to nodes near the blinded paths' introduction
nodes.
Invoices are authenticated by checking the payer metadata in the
corresponding invoice request or refund. For all invoices requests and
for refunds using blinded paths, this will be the encrypted payment id
and a 128-bit nonce. Allows checking the unencrypted payment id and
nonce explicitly instead of the payer metadata. This will be used by an
upcoming change that includes the payment id and nonce in the invoice
request's reply path and the refund's blinded paths instead of
completely in the payer metadata, which mitigates de-anonymization
attacks.
When using RefundBuilder::deriving_payer_id, the nonce generated needs
to be the same one included in any RefundBuilder::paths. This is because
the nonce is used along with the refund TLVs to derive a payer id and
will soon be used to authenticate any invoices.
When using InvoiceRequestBuilder::deriving_payer_id, the nonce generated
needs to be the same one included in any reply path. This is because the
nonce is used along with the invoice request TLVs to derive a payer id.
While this data is also included in the payer_metadata, including it in
the blinded path would allow reducing the amount of data needed there to
just enough to provide entropy (i.e., 16 bytes). This is more important
for Refund because it can be transmitted via a QR code. But using the
same payer_metadata structure for both InvoiceRequest and Refund would
be beneficial to avoid more code.
When an invoice or invoice request cannot be authenticated from an
OffersContext, simply do not respond instead of sending an InvoiceError
message. According to BOLT4, messages sent over a blinded path not
intended for its use MUST be ignored.
When a Bolt12Invoice is handled with an OfferContext, use the
containing payment_id to verify that it is for a pending outbound
payment. Only invoices for refunds without any blinded paths can be
verified without an OfferContext.
When an Offer uses blinded paths, its metadata consists of a nonce used
to derive its signing keys. Now that the blinded paths contain this
nonce, elide the metadata as it is now redundant. This saves space and
also makes it impossible to derive the signing keys if an invoice
request is received with the incorrect nonce. The nonce shouldn't be
revealed in this case either to prevent de-anonymization attacks.
When an InvoiceRequest is handled with an OfferContext, use the
containing nonce to verify that it is for a valid Offer. Otherwise, fall
back to using Offer::metadata, which also contains the nonce. The latter
is useful for supporting offers without blinded paths or those created
prior to including an OffersContext in their blinded paths.
To authenticate that an InvoiceRequest is for a valid Offer, include the
nonce from the Offer::metadata in the Offer::paths. This can be used to
prevent de-anonymization attacks where an attacker sends requests using
self-constructed paths to nodes near the Offer::paths' introduction
nodes.
