[Lightning-dev] Opening balanced channels using PSBT

2021-09-21 Thread Ole Henrik Skogstrøm
Hi I have found a way of opening balanced channels using LND's psbt option when opening channels. What I'm doing is essentially just joining funded PSBTs before signing and submitting them. This makes it possible to open a balanced channel between two nodes or open a ring of balanced channels

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread Joost Jager
On Tue, Sep 21, 2021 at 5:47 PM Bastien TEINTURIER wrote: > Hi Joost, > > Concept ACK, I had toyed with something similar a while ago, but I hadn't > realized > that invoice storage was such a DoS vector for merchants/hubs and wasn't > sure it > would be useful. > Yes, I definitely think it is.

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread Bastien TEINTURIER
Hi Joost, Concept ACK, I had toyed with something similar a while ago, but I hadn't realized that invoice storage was such a DoS vector for merchants/hubs and wasn't sure it would be useful. Do you have an example of what information you would usually put in your `encoded_order_details`? I'd

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread Joost Jager
On Tue, Sep 21, 2021 at 3:06 PM fiatjaf wrote: > I would say, however, that these are two separate proposals: > > 1. implementations should expose a "stateless invoice" API for receiving > using the payment_secret; > 2. when sending, implementations should attach a TLV record with encoded >

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread fiatjaf
Indeed, sorry, I misunderstood it because I read AMP/keysend and assumed you were talking about payer-generated preimage. It doesn't help that "payer" and "payee" are so similar words. So yes, I agree very much. I also think the part about including the order details inside the TLV would be very

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread Joost Jager
On Tue, Sep 21, 2021 at 2:05 PM fiatjaf wrote: > What if instead of the payer generating the preimage the payee could > generate stateless invoices? Basically just use some secret to compute the > preimage upon receiving the HTLC, for example: > Maybe my explanation wasn't clear enough, but

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread fiatjaf
What if instead of the payer generating the preimage the payee could generate stateless invoices? Basically just use some secret to compute the preimage upon receiving the HTLC, for example: 1. Payer requests an invoice. 2. Payee computes hash = sha256(hmac(local_secret, arbitrary_invoice_id)),

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread ZmnSCPxj via Lightning-dev
Good morning Joost, > > > preimage = H(node_secret | payment_secret | payment_amount | > > > encoded_order_details) > > > invoice_hash = H(preimage) > > > > > > The sender sends an htlc locked to invoice_hash for payment_amount and > > > passes along payment_secret and encoded_order_details in

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread ZmnSCPxj via Lightning-dev
Good morning again Joost, > However, we can do "pay for signature" protocols using PTLCs, and rather than > requesting for a scalar behind a point as the proof-of-payment, we can > instead ask for a signature of a message that attests "this recipient got > paid `payment_amount` with

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread Joost Jager
> > > preimage = H(node_secret | payment_secret | payment_amount | > encoded_order_details) > > invoice_hash = H(preimage) > > > > The sender sends an htlc locked to invoice_hash for payment_amount and > passes along payment_secret and encoded_order_details in a custom tlv > record. > > > > When

Re: [Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread ZmnSCPxj via Lightning-dev
Good morning Joost, > It could be something like this: > > payment_secret = random > preimage = H(node_secret | payment_secret | payment_amount | > encoded_order_details) > invoice_hash = H(preimage) > > The sender sends an htlc locked to invoice_hash for payment_amount and passes > along

[Lightning-dev] Stateless invoices with proof-of-payment

2021-09-21 Thread Joost Jager
Problem One of the qualities of lightning is that it can provide light-weight, no-login payments with minimal friction. Games, paywalls, podcasts, etc can immediately present a QR code that is ready for scan and pay. Optimistically presenting payment requests does lead to many of those payment