This fixes a potential bug where some NATs may replace the node's
interal IP with its external IP in version messages, causing
incorrect checksums when version messages begin being checksummed
on February 14, 2012.
When a transaction has multiple outputs that go to the wallet, list these
as multiple transactions in the UI. This is also applied to generated
(coinbase) transactions. Also makes the code shorter and easier
to understand.
Help users avoid insecure configurations a bit by recommending a
secure RPC password and increasing the incorrect password delay.
This may open up a RPC DOS for users with exposed RPC ports and
short passwords. Since users shouldn't have exposed RPC ports OR
short passwords, the DOS risk is preferable to the compromise
risk.
Also logs the client IP address for incorrect attempts.
This also avoids flushing setAddrKnown until 24 hours has passed,
and avoids contacting the external IP services when not listening.
Advertising non-listening nodes is just addr message spam.
It doesn't help the network, in fact it hurts the network,
and it also hurts user's privacy.
Advertising far out of sync nodes doesn't help the network—
they can't even forward (most) transactions and wastes nodes
outbound slots.
Allow mining of min-difficulty blocks if 20 minutes have gone by without mining a regular-difficulty block.
Normal rules apply every 2016 blocks, though, so there may be a very-slow-to-confirm block at the difficulty-adjustment blocks.
This also removes an un-needed sigops-per-byte check when accepting transactions to the memory pool (un-needed assuming only standard transactions are being accepted). And it only counts P2SH sigops after the switchover date.
base58-encoding of full/compressed public keys needs more thought; it probably makes sense to define a base58 encoding that includes a version byte and a checksum. So just support hex and bitcoin-address encodings for now.