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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

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1Bitcoin Core version 0.10.0 is now available from:
2
3  https://bitcoin.org/bin/0.10.0/
4
5This is a new major version release, bringing both new features and
6bug fixes.
7
8Please report bugs using the issue tracker at github:
9
10  https://github.com/bitcoin/bitcoin/issues
11
12Upgrading and downgrading
13=========================
14
15How to Upgrade
16--------------
17
18If you are running an older version, shut it down. Wait until it has completely
19shut down (which might take a few minutes for older versions), then run the
20installer (on Windows) or just copy over /Applications/Bitcoin-Qt (on Mac) or
21bitcoind/bitcoin-qt (on Linux).
22
23Downgrading warning
24---------------------
25
26Because release 0.10.0 makes use of headers-first synchronization and parallel
27block download (see further), the block files and databases are not
28backwards-compatible with older versions of Bitcoin Core or other software:
29
30* Blocks will be stored on disk out of order (in the order they are
31received, really), which makes it incompatible with some tools or
32other programs. Reindexing using earlier versions will also not work
33anymore as a result of this.
34
35* The block index database will now hold headers for which no block is
36stored on disk, which earlier versions won't support.
37
38If you want to be able to downgrade smoothly, make a backup of your entire data
39directory. Without this your node will need start syncing (or importing from
40bootstrap.dat) anew afterwards. It is possible that the data from a completely
41synchronised 0.10 node may be usable in older versions as-is, but this is not
42supported and may break as soon as the older version attempts to reindex.
43
44This does not affect wallet forward or backward compatibility.
45
46
47Notable changes
48===============
49
50Faster synchronization
51----------------------
52
53Bitcoin Core now uses 'headers-first synchronization'. This means that we first
54ask peers for block headers (a total of 27 megabytes, as of December 2014) and
55validate those. In a second stage, when the headers have been discovered, we
56download the blocks. However, as we already know about the whole chain in
57advance, the blocks can be downloaded in parallel from all available peers.
58
59In practice, this means a much faster and more robust synchronization. On
60recent hardware with a decent network link, it can be as little as 3 hours
61for an initial full synchronization. You may notice a slower progress in the
62very first few minutes, when headers are still being fetched and verified, but
63it should gain speed afterwards.
64
65A few RPCs were added/updated as a result of this:
66- `getblockchaininfo` now returns the number of validated headers in addition to
67the number of validated blocks.
68- `getpeerinfo` lists both the number of blocks and headers we know we have in
69common with each peer. While synchronizing, the heights of the blocks that we
70have requested from peers (but haven't received yet) are also listed as
71'inflight'.
72- A new RPC `getchaintips` lists all known branches of the block chain,
73including those we only have headers for.
74
75Transaction fee changes
76-----------------------
77
78This release automatically estimates how high a transaction fee (or how
79high a priority) transactions require to be confirmed quickly. The default
80settings will create transactions that confirm quickly; see the new
81'txconfirmtarget' setting to control the tradeoff between fees and
82confirmation times. Fees are added by default unless the 'sendfreetransactions' 
83setting is enabled.
84
85Prior releases used hard-coded fees (and priorities), and would
86sometimes create transactions that took a very long time to confirm.
87
88Statistics used to estimate fees and priorities are saved in the
89data directory in the `fee_estimates.dat` file just before
90program shutdown, and are read in at startup.
91
92New command line options for transaction fee changes:
93- `-txconfirmtarget=n` : create transactions that have enough fees (or priority)
94so they are likely to begin confirmation within n blocks (default: 1). This setting
95is over-ridden by the -paytxfee option.
96- `-sendfreetransactions` : Send transactions as zero-fee transactions if possible 
97(default: 0)
98
99New RPC commands for fee estimation:
100- `estimatefee nblocks` : Returns approximate fee-per-1,000-bytes needed for
101a transaction to begin confirmation within nblocks. Returns -1 if not enough
102transactions have been observed to compute a good estimate.
103- `estimatepriority nblocks` : Returns approximate priority needed for
104a zero-fee transaction to begin confirmation within nblocks. Returns -1 if not
105enough free transactions have been observed to compute a good
106estimate.
107
108RPC access control changes
109--------------------------
110
111Subnet matching for the purpose of access control is now done
112by matching the binary network address, instead of with string wildcard matching.
113For the user this means that `-rpcallowip` takes a subnet specification, which can be
114
115- a single IP address (e.g. `1.2.3.4` or `fe80::0012:3456:789a:bcde`)
116- a network/CIDR (e.g. `1.2.3.0/24` or `fe80::0000/64`)
117- a network/netmask (e.g. `1.2.3.4/255.255.255.0` or `fe80::0012:3456:789a:bcde/ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff`)
118
119An arbitrary number of `-rpcallow` arguments can be given. An incoming connection will be accepted if its origin address
120matches one of them.
121
122For example:
123
124| 0.9.x and before                           | 0.10.x                                |
125|--------------------------------------------|---------------------------------------|
126| `-rpcallowip=192.168.1.1`                  | `-rpcallowip=192.168.1.1` (unchanged) |
127| `-rpcallowip=192.168.1.*`                  | `-rpcallowip=192.168.1.0/24`          |
128| `-rpcallowip=192.168.*`                    | `-rpcallowip=192.168.0.0/16`          |
129| `-rpcallowip=*` (dangerous!)               | `-rpcallowip=::/0` (still dangerous!) |
130
131Using wildcards will result in the rule being rejected with the following error in debug.log:
132
133    Error: Invalid -rpcallowip subnet specification: *. Valid are a single IP (e.g. 1.2.3.4), a network/netmask (e.g. 1.2.3.4/255.255.255.0) or a network/CIDR (e.g. 1.2.3.4/24).
134
135
136REST interface
137--------------
138
139A new HTTP API is exposed when running with the `-rest` flag, which allows
140unauthenticated access to public node data.
141
142It is served on the same port as RPC, but does not need a password, and uses
143plain HTTP instead of JSON-RPC.
144
145Assuming a local RPC server running on port 8332, it is possible to request:
146- Blocks: http://localhost:8332/rest/block/*HASH*.*EXT*
147- Blocks without transactions: http://localhost:8332/rest/block/notxdetails/*HASH*.*EXT*
148- Transactions (requires `-txindex`): http://localhost:8332/rest/tx/*HASH*.*EXT*
149
150In every case, *EXT* can be `bin` (for raw binary data), `hex` (for hex-encoded
151binary) or `json`.
152
153For more details, see the `doc/REST-interface.md` document in the repository.
154
155RPC Server "Warm-Up" Mode
156-------------------------
157
158The RPC server is started earlier now, before most of the expensive
159intialisations like loading the block index.  It is available now almost
160immediately after starting the process.  However, until all initialisations
161are done, it always returns an immediate error with code -28 to all calls.
162
163This new behaviour can be useful for clients to know that a server is already
164started and will be available soon (for instance, so that they do not
165have to start it themselves).
166
167Improved signing security
168-------------------------
169
170For 0.10 the security of signing against unusual attacks has been
171improved by making the signatures constant time and deterministic.
172
173This change is a result of switching signing to use libsecp256k1
174instead of OpenSSL. Libsecp256k1 is a cryptographic library
175optimized for the curve Bitcoin uses which was created by Bitcoin
176Core developer Pieter Wuille.
177
178There exist attacks[1] against most ECC implementations where an
179attacker on shared virtual machine hardware could extract a private
180key if they could cause a target to sign using the same key hundreds
181of times. While using shared hosts and reusing keys are inadvisable
182for other reasons, it's a better practice to avoid the exposure.
183
184OpenSSL has code in their source repository for derandomization
185and reduction in timing leaks that we've eagerly wanted to use for a
186long time, but this functionality has still not made its
187way into a released version of OpenSSL. Libsecp256k1 achieves
188significantly stronger protection: As far as we're aware this is
189the only deployed implementation of constant time signing for
190the curve Bitcoin uses and we have reason to believe that
191libsecp256k1 is better tested and more thoroughly reviewed
192than the implementation in OpenSSL.
193
194[1] https://eprint.iacr.org/2014/161.pdf
195
196Watch-only wallet support
197-------------------------
198
199The wallet can now track transactions to and from wallets for which you know
200all addresses (or scripts), even without the private keys.
201
202This can be used to track payments without needing the private keys online on a
203possibly vulnerable system. In addition, it can help for (manual) construction
204of multisig transactions where you are only one of the signers.
205
206One new RPC, `importaddress`, is added which functions similarly to
207`importprivkey`, but instead takes an address or script (in hexadecimal) as
208argument.  After using it, outputs credited to this address or script are
209considered to be received, and transactions consuming these outputs will be
210considered to be sent.
211
212The following RPCs have optional support for watch-only:
213`getbalance`, `listreceivedbyaddress`, `listreceivedbyaccount`,
214`listtransactions`, `listaccounts`, `listsinceblock`, `gettransaction`. See the
215RPC documentation for those methods for more information.
216
217Compared to using `getrawtransaction`, this mechanism does not require
218`-txindex`, scales better, integrates better with the wallet, and is compatible
219with future block chain pruning functionality. It does mean that all relevant
220addresses need to added to the wallet before the payment, though.
221
222Consensus library
223-----------------
224
225Starting from 0.10.0, the Bitcoin Core distribution includes a consensus library.
226
227The purpose of this library is to make the verification functionality that is
228critical to Bitcoin's consensus available to other applications, e.g. to language
229bindings such as [python-bitcoinlib](https://pypi.python.org/pypi/python-bitcoinlib) or
230alternative node implementations.
231
232This library is called `libbitcoinconsensus.so` (or, `.dll` for Windows).
233Its interface is defined in the C header [bitcoinconsensus.h](https://github.com/bitcoin/bitcoin/blob/0.10/src/script/bitcoinconsensus.h).
234
235In its initial version the API includes two functions:
236
237- `bitcoinconsensus_verify_script` verifies a script. It returns whether the indicated input of the provided serialized transaction 
238correctly spends the passed scriptPubKey under additional constraints indicated by flags
239- `bitcoinconsensus_version` returns the API version, currently at an experimental `0`
240
241The functionality is planned to be extended to e.g. UTXO management in upcoming releases, but the interface
242for existing methods should remain stable.
243
244Standard script rules relaxed for P2SH addresses
245------------------------------------------------
246
247The IsStandard() rules have been almost completely removed for P2SH
248redemption scripts, allowing applications to make use of any valid
249script type, such as "n-of-m OR y", hash-locked oracle addresses, etc.
250While the Bitcoin protocol has always supported these types of script,

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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