Inside Bitcoin

251actually using them on mainnet has been previously inconvenient as
252standard Bitcoin Core nodes wouldn't relay them to miners, nor would
253most miners include them in blocks they mined.
254
255bitcoin-tx
256----------
257
258It has been observed that many of the RPC functions offered by bitcoind are
259"pure functions", and operate independently of the bitcoind wallet. This
260included many of the RPC "raw transaction" API functions, such as
261createrawtransaction.
262
263bitcoin-tx is a newly introduced command line utility designed to enable easy
264manipulation of bitcoin transactions. A summary of its operation may be
265obtained via "bitcoin-tx --help" Transactions may be created or signed in a
266manner similar to the RPC raw tx API. Transactions may be updated, deleting
267inputs or outputs, or appending new inputs and outputs. Custom scripts may be
268easily composed using a simple text notation, borrowed from the bitcoin test
269suite.
270
271This tool may be used for experimenting with new transaction types, signing
272multi-party transactions, and many other uses. Long term, the goal is to
273deprecate and remove "pure function" RPC API calls, as those do not require a
274server round-trip to execute.
275
276Other utilities "bitcoin-key" and "bitcoin-script" have been proposed, making
277key and script operations easily accessible via command line.
278
279Mining and relay policy enhancements
280------------------------------------
281
282Bitcoin Core's block templates are now for version 3 blocks only, and any mining
283software relying on its `getblocktemplate` must be updated in parallel to use
284libblkmaker either version 0.4.2 or any version from 0.5.1 onward.
285If you are solo mining, this will affect you the moment you upgrade Bitcoin
286Core, which must be done prior to BIP66 achieving its 951/1001 status.
287If you are mining with the stratum mining protocol: this does not affect you.
288If you are mining with the getblocktemplate protocol to a pool: this will affect
289you at the pool operator's discretion, which must be no later than BIP66
290achieving its 951/1001 status.
291
292The `prioritisetransaction` RPC method has been added to enable miners to
293manipulate the priority of transactions on an individual basis.
294
295Bitcoin Core now supports BIP 22 long polling, so mining software can be
296notified immediately of new templates rather than having to poll periodically.
297
298Support for BIP 23 block proposals is now available in Bitcoin Core's
299`getblocktemplate` method. This enables miners to check the basic validity of
300their next block before expending work on it, reducing risks of accidental
301hardforks or mining invalid blocks.
302
303Two new options to control mining policy:
304- `-datacarrier=0/1` : Relay and mine "data carrier" (OP_RETURN) transactions
305if this is 1.
306- `-datacarriersize=n` : Maximum size, in bytes, we consider acceptable for
307"data carrier" outputs.
308
309The relay policy has changed to more properly implement the desired behavior of not 
310relaying free (or very low fee) transactions unless they have a priority above the 
311AllowFreeThreshold(), in which case they are relayed subject to the rate limiter.
312
313BIP 66: strict DER encoding for signatures
314------------------------------------------
315
316Bitcoin Core 0.10 implements BIP 66, which introduces block version 3, and a new
317consensus rule, which prohibits non-DER signatures. Such transactions have been
318non-standard since Bitcoin v0.8.0 (released in February 2013), but were
319technically still permitted inside blocks.
320
321This change breaks the dependency on OpenSSL's signature parsing, and is
322required if implementations would want to remove all of OpenSSL from the
323consensus code.
324
325The same miner-voting mechanism as in BIP 34 is used: when 751 out of a
326sequence of 1001 blocks have version number 3 or higher, the new consensus
327rule becomes active for those blocks. When 951 out of a sequence of 1001
328blocks have version number 3 or higher, it becomes mandatory for all blocks.
329
330Backward compatibility with current mining software is NOT provided, thus miners
331should read the first paragraph of "Mining and relay policy enhancements" above.
332
3330.10.0 Change log
334=================
335
336Detailed release notes follow. This overview includes changes that affect external
337behavior, not code moves, refactors or string updates.
338
339RPC:
340- `f923c07` Support IPv6 lookup in bitcoin-cli even when IPv6 only bound on localhost
341- `b641c9c` Fix addnode "onetry": Connect with OpenNetworkConnection
342- `171ca77` estimatefee / estimatepriority RPC methods
343- `b750cf1` Remove cli functionality from bitcoind
344- `f6984e8` Add "chain" to getmininginfo, improve help in getblockchaininfo
345- `99ddc6c` Add nLocalServices info to RPC getinfo
346- `cf0c47b` Remove getwork() RPC call
347- `2a72d45` prioritisetransaction <txid> <priority delta> <priority tx fee>
348- `e44fea5` Add an option `-datacarrier` to allow users to disable relaying/mining data carrier transactions
349- `2ec5a3d` Prevent easy RPC memory exhaustion attack
350- `d4640d7` Added argument to getbalance to include watchonly addresses and fixed errors in balance calculation
351- `83f3543` Added argument to listaccounts to include watchonly addresses
352- `952877e` Showing 'involvesWatchonly' property for transactions returned by 'listtransactions' and 'listsinceblock'. It is only appended when the transaction involves a watchonly address
353- `d7d5d23` Added argument to listtransactions and listsinceblock to include watchonly addresses
354- `f87ba3d` added includeWatchonly argument to 'gettransaction' because it affects balance calculation
355- `0fa2f88` added includedWatchonly argument to listreceivedbyaddress/...account
356- `6c37f7f` `getrawchangeaddress`: fail when keypool exhausted and wallet locked
357- `ff6a7af` getblocktemplate: longpolling support
358- `c4a321f` Add peerid to getpeerinfo to allow correlation with the logs
359- `1b4568c` Add vout to ListTransactions output
360- `b33bd7a` Implement "getchaintips" RPC command to monitor blockchain forks
361- `733177e` Remove size limit in RPC client, keep it in server
362- `6b5b7cb` Categorize rpc help overview
363- `6f2c26a` Closely track mempool byte total. Add "getmempoolinfo" RPC
364- `aa82795` Add detailed network info to getnetworkinfo RPC
365- `01094bd` Don't reveal whether password is <20 or >20 characters in RPC
366- `57153d4` rpc: Compute number of confirmations of a block from block height
367- `ff36cbe` getnetworkinfo: export local node's client sub-version string
368- `d14d7de` SanitizeString: allow '(' and ')'
369- `31d6390` Fixed setaccount accepting foreign address
370- `b5ec5fe` update getnetworkinfo help with subversion
371- `ad6e601` RPC additions after headers-first
372- `33dfbf5` rpc: Fix leveldb iterator leak, and flush before `gettxoutsetinfo`
373- `2aa6329` Enable customising node policy for datacarrier data size with a -datacarriersize option
374- `f877aaa` submitblock: Use a temporary CValidationState to determine accurately the outcome of ProcessBlock
375- `e69a587` submitblock: Support for returning specific rejection reasons
376- `af82884` Add "warmup mode" for RPC server
377- `e2655e0` Add unauthenticated HTTP REST interface to public blockchain data
378- `683dc40` Disable SSLv3 (in favor of TLS) for the RPC client and server
379- `44b4c0d` signrawtransaction: validate private key
380- `9765a50` Implement BIP 23 Block Proposal
381- `f9de17e` Add warning comment to getinfo
382
383Command-line options:
384- `ee21912` Use netmasks instead of wildcards for IP address matching
385- `deb3572` Add `-rpcbind` option to allow binding RPC port on a specific interface
386- `96b733e` Add `-version` option to get just the version
387- `1569353` Add `-stopafterblockimport` option
388- `77cbd46` Let -zapwallettxes recover transaction meta data
389- `1c750db` remove -tor compatibility code (only allow -onion)
390- `4aaa017` rework help messages for fee-related options
391- `4278b1d` Clarify error message when invalid -rpcallowip
392- `6b407e4` -datadir is now allowed in config files
393- `bdd5b58` Add option `-sysperms` to disable 077 umask (create new files with system default umask)
394- `cbe39a3` Add "bitcoin-tx" command line utility and supporting modules
395- `dbca89b` Trigger -alertnotify if network is upgrading without you
396- `ad96e7c` Make -reindex cope with out-of-order blocks
397- `16d5194` Skip reindexed blocks individually
398- `ec01243` --tracerpc option for regression tests
399- `f654f00` Change -genproclimit default to 1
400- `3c77714` Make -proxy set all network types, avoiding a connect leak
401- `57be955` Remove -printblock, -printblocktree, and -printblockindex
402- `ad3d208` remove -maxorphanblocks config parameter since it is no longer functional
403
404Block and transaction handling:
405- `7a0e84d` ProcessGetData(): abort if a block file is missing from disk
406- `8c93bf4` LoadBlockIndexDB(): Require block db reindex if any `blk*.dat` files are missing
407- `77339e5` Get rid of the static chainMostWork (optimization)
408- `4e0eed8` Allow ActivateBestChain to release its lock on cs_main
409- `18e7216` Push cs_mains down in ProcessBlock
410- `fa126ef` Avoid undefined behavior using CFlatData in CScript serialization
411- `7f3b4e9` Relax IsStandard rules for pay-to-script-hash transactions
412- `c9a0918` Add a skiplist to the CBlockIndex structure
413- `bc42503` Use unordered_map for CCoinsViewCache with salted hash (optimization)
414- `d4d3fbd` Do not flush the cache after every block outside of IBD (optimization)
415- `ad08d0b` Bugfix: make CCoinsViewMemPool support pruned entries in underlying cache
416- `5734d4d` Only remove actualy failed blocks from setBlockIndexValid
417- `d70bc52` Rework block processing benchmark code
418- `714a3e6` Only keep setBlockIndexValid entries that are possible improvements
419- `ea100c7` Reduce maximum coinscache size during verification (reduce memory usage)
420- `4fad8e6` Reject transactions with excessive numbers of sigops
421- `b0875eb` Allow BatchWrite to destroy its input, reducing copying (optimization)
422- `92bb6f2` Bypass reloading blocks from disk (optimization)
423- `2e28031` Perform CVerifyDB on pcoinsdbview instead of pcoinsTip (reduce memory usage)
424- `ab15b2e` Avoid copying undo data (optimization)
425- `341735e` Headers-first synchronization
426- `afc32c5` Fix rebuild-chainstate feature and improve its performance
427- `e11b2ce` Fix large reorgs
428- `ed6d1a2` Keep information about all block files in memory
429- `a48f2d6` Abstract context-dependent block checking from acceptance
430- `7e615f5` Fixed mempool sync after sending a transaction
431- `51ce901` Improve chainstate/blockindex disk writing policy
432- `a206950` Introduce separate flushing modes
433- `9ec75c5` Add a locking mechanism to IsInitialBlockDownload to ensure it never goes from false to true
434- `868d041` Remove coinbase-dependant transactions during reorg
435- `723d12c` Remove txn which are invalidated by coinbase maturity during reorg
436- `0cb8763` Check against MANDATORY flags prior to accepting to mempool
437- `8446262` Reject headers that build on an invalid parent
438- `008138c` Bugfix: only track UTXO modification after lookup
439
440P2P protocol and network code:
441- `f80cffa` Do not trigger a DoS ban if SCRIPT_VERIFY_NULLDUMMY fails
442- `c30329a` Add testnet DNS seed of Alex Kotenko
443- `45a4baf` Add testnet DNS seed of Andreas Schildbach
444- `f1920e8` Ping automatically every 2 minutes (unconditionally)
445- `806fd19` Allocate receive buffers in on the fly
446- `6ecf3ed` Display unknown commands received
447- `aa81564` Track peers' available blocks
448- `caf6150` Use async name resolving to improve net thread responsiveness
449- `9f4da19` Use pong receive time rather than processing time
450- `0127a9b` remove SOCKS4 support from core and GUI, use SOCKS5
451- `40f5cb8` Send rejects and apply DoS scoring for errors in direct block validation
452- `dc942e6` Introduce whitelisted peers
453- `c994d2e` prevent SOCKET leak in BindListenPort()
454- `a60120e` Add built-in seeds for .onion
455- `60dc8e4` Allow -onlynet=onion to be used
456- `3a56de7` addrman: Do not propagate obviously poor addresses onto the network
457- `6050ab6` netbase: Make SOCKS5 negotiation interruptible
458- `604ee2a` Remove tx from AlreadyAskedFor list once we receive it, not when we process it
459- `efad808` Avoid reject message feedback loops
460- `71697f9` Separate protocol versioning from clientversion
461- `20a5f61` Don't relay alerts to peers before version negotiation
462- `b4ee0bd` Introduce preferred download peers
463- `845c86d` Do not use third party services for IP detection
464- `12a49ca` Limit the number of new addressses to accumulate
465- `35e408f` Regard connection failures as attempt for addrman
466- `a3a7317` Introduce 10 minute block download timeout
467- `3022e7d` Require sufficent priority for relay of free transactions
468- `58fda4d` Update seed IPs, based on bitcoin.sipa.be crawler data
469- `18021d0` Remove bitnodes.io from dnsseeds.
470
471Validation:
472- `6fd7ef2` Also switch the (unused) verification code to low-s instead of even-s
473- `584a358` Do merkle root and txid duplicates check simultaneously
474- `217a5c9` When transaction outputs exceed inputs, show the offending amounts so as to aid debugging
475- `f74fc9b` Print input index when signature validation fails, to aid debugging
476- `6fd59ee` script.h: set_vch() should shift a >32 bit value
477- `d752ba8` Add SCRIPT_VERIFY_SIGPUSHONLY (BIP62 rule 2) (test only)
478- `698c6ab` Add SCRIPT_VERIFY_MINIMALDATA (BIP62 rules 3 and 4) (test only)
479- `ab9edbd` script: create sane error return codes for script validation and remove logging
480- `219a147` script: check ScriptError values in script tests
481- `0391423` Discourage NOPs reserved for soft-fork upgrades
482- `98b135f` Make STRICTENC invalid pubkeys fail the script rather than the opcode
483- `307f7d4` Report script evaluation failures in log and reject messages
484- `ace39db` consensus: guard against openssl's new strict DER checks
485- `12b7c44` Improve robustness of DER recoding code
486- `76ce5c8` fail immediately on an empty signature
487
488Build system:
489- `f25e3ad` Fix build in OS X 10.9
490- `65e8ba4` build: Switch to non-recursive make
491- `460b32d` build: fix broken boost chrono check on some platforms
492- `9ce0774` build: Fix windows configure when using --with-qt-libdir
493- `ea96475` build: Add mention of --disable-wallet to bdb48 error messages
494- `1dec09b` depends: add shared dependency builder
495- `c101c76` build: Add --with-utils (bitcoin-cli and bitcoin-tx, default=yes). Help string consistency tweaks. Target sanity check fix
496- `e432a5f` build: add option for reducing exports (v2)
497- `6134b43` Fixing condition 'sabotaging' MSVC build
498- `af0bd5e` osx: fix signing to make Gatekeeper happy (again)
499- `a7d1f03` build: fix dynamic boost check when --with-boost= is used
500- `d5fd094` build: fix qt test build when libprotobuf is in a non-standard path