From 8127685462a3438377813970562aebff801d39ac Mon Sep 17 00:00:00 2001 From: Olaoluwa Osuntokun Date: Sun, 18 Mar 2018 16:58:39 -0700 Subject: [PATCH] funding+rpc: raise min channel size to 20k satoshis In this commit, we raise the min channel size to 20k satoshis. This will be evaluated before we check for dusty commitments. The goal of this is to ensure ample room for fees at current, and future fee levels. --- fundingmanager.go | 4 ++++ rpcserver.go | 23 +++++++++++++---------- 2 files changed, 17 insertions(+), 10 deletions(-) diff --git a/fundingmanager.go b/fundingmanager.go index 607a91e78..87db5a95a 100644 --- a/fundingmanager.go +++ b/fundingmanager.go @@ -60,6 +60,10 @@ const ( // for the funding transaction to be confirmed before forgetting about // the channel. 288 blocks is ~48 hrs maxWaitNumBlocksFundingConf = 288 + + // minChanFundingSize is the smallest channel that we'll allow to be + // created over the RPC interface. + minChanFundingSize = btcutil.Amount(20000) ) // reservationWithCtx encapsulates a pending channel reservation. This wrapper diff --git a/rpcserver.go b/rpcserver.go index be6bbc9d8..2ca138091 100644 --- a/rpcserver.go +++ b/rpcserver.go @@ -701,17 +701,12 @@ func (r *rpcServer) OpenChannel(in *lnrpc.OpenChannelRequest, "channel size is: %v", maxFundingAmount) } - const minChannelSize = btcutil.Amount(6000) - - // Restrict the size of the channel we'll actually open. Atm, we - // require the amount to be above 6k satoshis we currently hard-coded - // a 5k satoshi fee in several areas. As a result 6k sat is the min - // channel size that allows us to safely sit above the dust threshold - // after fees are applied - // TODO(roasbeef): remove after dynamic fees are in - if localFundingAmt < minChannelSize { + // Restrict the size of the channel we'll actually open. At a later + // level, we'll ensure that the output we create after accounting for + // fees that a dust output isn't created. + if localFundingAmt < minChanFundingSize { return fmt.Errorf("channel is too small, the minimum channel "+ - "size is: %v (6k sat)", minChannelSize) + "size is: %v SAT", int64(minChanFundingSize)) } var ( @@ -864,6 +859,14 @@ func (r *rpcServer) OpenChannelSync(ctx context.Context, "initial state must be below the local funding amount") } + // Restrict the size of the channel we'll actually open. At a later + // level, we'll ensure that the output we create after accounting for + // fees that a dust output isn't created. + if localFundingAmt < minChanFundingSize { + return nil, fmt.Errorf("channel is too small, the minimum channel "+ + "size is: %v SAT", int64(minChanFundingSize)) + } + // Based on the passed fee related parameters, we'll determine an // appropriate fee rate for the funding transaction. feeRate, err := determineFeePerVSize(