Remove peer exchange from main; it was merged unreviewed (#27)

PR #25 was opened, reviewed and approved as a single-file change to net.cpp:
the .btf peer cache, +169/-0. I then pushed peer exchange and a /port option
onto that same branch while the PR was open, which silently widened it to six
files. The merge carried all of it in.

Nothing about the peer exchange had been validated. Its two-node test never
completed -- node B could not dial node A at all -- so what landed on main is
unproven network protocol code that no one agreed to take.

This restores main to what #25 actually described. The peer cache stays, with
its runtime numbers (36.3s to 2.1s to first peer). #26 stays. What comes out:

- the "btfpeers" message, both directions
- BtfPexCollect / BtfPexAccept and the per-message caps
- CNode::nLastPexRecv
- the `desc` field on the cached peer record
- BtfLocalDescriptor / BtfSecpContext
- /port

Peer exchange returns as its own pull request once its test passes. The /port
option is worth having on its own -- two nodes cannot share a machine without
it, which is what blocked the test -- and should go up separately rather than
ride along again.

Release v1.2.2 is unaffected: it was built from ba2de82, before either merge.

1 files changed, 0 insertions, 19 deletions

diff --git a/src/net.h b/src/net.h
index 7d70721..f028c3b 100644
--- a/src/net.h
+++ b/src/net.h
@@ -29,21 +29,6 @@ CNode* ConnectNodeBtfResolved(const string& strBtfAddr, const string& strMeeting
 void ThreadBtfAccept(void* parg);
 void ThreadBtfConnect(void* parg);
 extern string strBtfConnect;
-
-// --- .btf peer exchange ---------------------------------------------------
-// Peers gossip signed descriptors so discovery survives a relay outage. Both
-// caps apply to a single "btfpeers" message; the generic header limit is 256 MB,
-// which is no protection at all for something a stranger can send unprompted.
-static const unsigned int MAX_PEX_DESCRIPTORS      = 20;
-static const unsigned int MAX_PEX_DESCRIPTOR_BYTES = 1024;
-// Ignore a peer's exchange more often than this. One announcement per side per
-// connection is the intended traffic; anything faster is someone else's idea.
-static const int64        PEX_MIN_INTERVAL         = 60;
-
-// Descriptors to hand a peer: ours first, then peers that answered us.
-void BtfPexCollect(std::vector<std::string>& vDescOut);
-// Verify descriptors a peer sent and remember the good ones. Returns how many.
-int  BtfPexAccept(const std::vector<std::string>& vDesc);
 void AbandonRequests(void (*fn)(void*, CDataStream&), void* param1);
 bool AnySubscribed(unsigned int nChannel);
 void ThreadBitcoinMiner(void* parg);
@@ -482,9 +467,6 @@ public:
     // publish and subscription
     vector<char> vfSubscribe;
 
-    // Last "btfpeers" we accepted from this node, to rate-limit the exchange.
-    int64 nLastPexRecv;
-
 
     CNode(SOCKET hSocketIn, CAddress addrIn, bool fInboundIn=false)
     {
@@ -501,7 +483,6 @@ public:
         fDisconnect = false;
         nRefCount = 0;
         nReleaseTime = 0;
-        nLastPexRecv = 0;
         vfSubscribe.assign(256, false);
 
         // Push a version message