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The code behind the network, with room to understand it.

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 0.18.0 is now available from:
2
3  <https://bitcoincore.org/bin/bitcoin-core-0.18.0/>
4
5This is a new major version release, including new features, various bug
6fixes and performance improvements, as well as updated translations.
7
8Please report bugs using the issue tracker at GitHub:
9
10  <https://github.com/bitcoin/bitcoin/issues>
11
12To receive security and update notifications, please subscribe to:
13
14  <https://bitcoincore.org/en/list/announcements/join/>
15
16How to Upgrade
17==============
18
19If you are running an older version, shut it down. Wait until it has
20completely shut down (which might take a few minutes for older
21versions), then run the installer (on Windows) or just copy over
22`/Applications/Bitcoin-Qt` (on Mac) or `bitcoind`/`bitcoin-qt` (on
23Linux).
24
25The first time you run version 0.15.0 or newer, your chainstate database
26will be converted to a new format, which will take anywhere from a few
27minutes to half an hour, depending on the speed of your machine.
28
29Note that the block database format also changed in version 0.8.0 and
30there is no automatic upgrade code from before version 0.8 to version
310.15.0 or later. Upgrading directly from 0.7.x and earlier without
32redownloading the blockchain is not supported.  However, as usual, old
33wallet versions are still supported.
34
35Compatibility
36==============
37
38Bitcoin Core is supported and extensively tested on operating systems
39using the Linux kernel, macOS 10.10+, and Windows 7 and newer. It is not
40recommended to use Bitcoin Core on unsupported systems.
41
42Bitcoin Core should also work on most other Unix-like systems but is not
43as frequently tested on them.
44
45From 0.17.0 onwards, macOS <10.10 is no longer supported. 0.17.0 is
46built using Qt 5.9.x, which doesn't support versions of macOS older than
4710.10. Additionally, Bitcoin Core does not yet change appearance when
48macOS "dark mode" is activated.
49
50In addition to previously-supported CPU platforms, this release's
51pre-compiled distribution also provides binaries for the RISC-V
52platform.
53
54If you are using the `systemd` unit configuration file located at
55`contrib/init/bitcoind.service`, it has been changed to use
56`/var/lib/bitcoind` as the data directory instead of
57`~bitcoin/.bitcoin`. When switching over to the new configuration file,
58please make sure that the filesystem on which `/var/lib/bitcoind` will
59exist has enough space (check using `df -h /var/lib/bitcoind`), and
60optionally copy over your existing data directory. See the [systemd init
61file section](#systemd-init-file) for more details.
62
63Known issues
64============
65
66Wallet GUI
67----------
68
69For advanced users who have both (1) enabled coin control features, and
70(2) are using multiple wallets loaded at the same time: The coin control
71input selection dialog can erroneously retain wrong-wallet state when
72switching wallets using the dropdown menu. For now, it is recommended
73not to use coin control features with multiple wallets loaded.
74
75Notable changes
76===============
77
78Mining
79------
80
81- Calls to `getblocktemplate` will fail if the segwit rule is not
82  specified.  Calling `getblocktemplate` without segwit specified is
83  almost certainly a misconfiguration since doing so results in lower
84  rewards for the miner.  Failed calls will produce an error message
85  describing how to enable the segwit rule.
86
87Configuration option changes
88----------------------------
89
90- A warning is printed if an unrecognized section name is used in the
91  configuration file.  Recognized sections are `[test]`, `[main]`, and
92  `[regtest]`.
93
94- Four new options are available for configuring the maximum number of
95  messages that ZMQ will queue in memory (the "high water mark") before
96  dropping additional messages.  The default value is 1,000, the same as
97  was used for previous releases.  See the [ZMQ
98  documentation](https://github.com/bitcoin/bitcoin/blob/master/doc/zmq.md#usage)
99  for details.
100
101- The `rpcallowip` option can no longer be used to automatically listen
102  on all network interfaces.  Instead, the `rpcbind` parameter must be
103  used to specify the IP addresses to listen on.  Listening for RPC
104  commands over a public network connection is insecure and should be
105  disabled, so a warning is now printed if a user selects such a
106  configuration.  If you need to expose RPC in order to use a tool like
107  Docker, ensure you only bind RPC to your localhost, e.g. `docker run
108  [...] -p 127.0.0.1:8332:8332` (this is an extra `:8332` over the
109  normal Docker port specification).
110
111- The `rpcpassword` option now causes a startup error if the password
112  set in the configuration file contains a hash character (#), as it's
113  ambiguous whether the hash character is meant for the password or as a
114  comment.
115
116- The `whitelistforcerelay` option is used to relay transactions from
117  whitelisted peers even when not accepted to the mempool. This option
118  now defaults to being off, so that changes in policy and
119  disconnect/ban behavior will not cause a node that is whitelisting
120  another to be dropped by peers.  Users can still explicitly enable
121  this behavior with the command line option (and may want to consider
122  [contacting](https://bitcoincore.org/en/contact/) the Bitcoin Core
123  project to let us know about their use-case, as this feature could be
124  deprecated in the future).
125
126systemd init file
127-----------------
128
129The systemd init file (`contrib/init/bitcoind.service`) has been changed
130to use `/var/lib/bitcoind` as the data directory instead of
131`~bitcoin/.bitcoin`. This change makes Bitcoin Core more consistent with
132other services, and makes the systemd init config more consistent with
133existing Upstart and OpenRC configs.
134
135The configuration, PID, and data directories are now completely managed
136by systemd, which will take care of their creation, permissions, etc.
137See [`systemd.exec(5)`](https://www.freedesktop.org/software/systemd/man/systemd.exec.html#RuntimeDirectory=)
138for more details.
139
140When using the provided init files under `contrib/init`, overriding the
141`datadir` option in `/etc/bitcoin/bitcoin.conf` will have no effect.
142This is because the command line arguments specified in the init files
143take precedence over the options specified in
144`/etc/bitcoin/bitcoin.conf`.
145
146
147Documentation
148-------------
149
150- A new short [document](https://github.com/bitcoin/bitcoin/blob/master/doc/JSON-RPC-interface.md)
151  about the JSON-RPC interface describes cases where the results of an
152  RPC might contain inconsistencies between data sourced from different
153  subsystems, such as wallet state and mempool state.  A note is added
154  to the [REST interface documentation](https://github.com/bitcoin/bitcoin/blob/master/doc/REST-interface.md)
155  indicating that the same rules apply.
156
157- Further information is added to the [JSON-RPC
158  documentation](https://github.com/bitcoin/bitcoin/blob/master/doc/JSON-RPC-interface.md)
159  about how to secure this interface.
160
161- A new [document](https://github.com/bitcoin/bitcoin/blob/master/doc/bitcoin-conf.md)
162  about the `bitcoin.conf` file describes how to use it to configure
163  Bitcoin Core.
164
165- A new document introduces Bitcoin Core's BIP174 [Partially-Signed
166  Bitcoin Transactions
167  (PSBT)](https://github.com/bitcoin/bitcoin/blob/master/doc/psbt.md)
168  interface, which is used to allow multiple programs to collaboratively
169  work to create, sign, and broadcast new transactions.  This is useful
170  for offline (cold storage) wallets, multisig wallets, coinjoin
171  implementations, and many other cases where two or more programs need
172  to interact to generate a complete transaction.
173
174- The [output script
175  descriptor](https://github.com/bitcoin/bitcoin/blob/master/doc/descriptors.md)
176  documentation has been updated with information about new features in
177  this still-developing language for describing the output scripts that
178  a wallet or other program wants to receive notifications for, such as
179  which addresses it wants to know received payments.  The language is
180  currently used in multiple new and updated RPCs described in these
181  release notes and is expected to be adapted to other RPCs and to the
182  underlying wallet structure.
183
184Build system changes
185--------------------
186
187- A new `--disable-bip70` option may be passed to `./configure` to
188  prevent Bitcoin-Qt from being built with support for the BIP70 payment
189  protocol or from linking libssl.  As the payment protocol has exposed
190  Bitcoin Core to libssl vulnerabilities in the past, builders who don't
191  need BIP70 support are encouraged to use this option to reduce their
192  exposure to future vulnerabilities.
193
194- The minimum required version of Qt (when building the GUI) has been
195  increased from 5.2 to 5.5.1 (the [depends
196  system](https://github.com/bitcoin/bitcoin/blob/master/depends/README.md)
197  provides 5.9.7)
198
199New RPCs
200--------
201
202- `getnodeaddresses` returns peer addresses known to this node. It may
203  be used to find nodes to connect to without using a DNS seeder.
204
205- `listwalletdir` returns a list of wallets in the wallet directory
206  (either the default wallet directory or the directory configured by
207  the `-walletdir` parameter).
208
209- `getrpcinfo` returns runtime details of the RPC server. At the moment,
210  it returns an array of the currently active commands and how long
211  they've been running.
212
213- `deriveaddresses` returns one or more addresses corresponding to an
214  [output descriptor](https://github.com/bitcoin/bitcoin/blob/master/doc/descriptors.md).
215
216- `getdescriptorinfo` accepts a descriptor and returns information about
217  it, including its computed checksum.
218
219- `joinpsbts` merges multiple distinct PSBTs into a single PSBT. The
220  multiple PSBTs must have different inputs. The resulting PSBT will
221  contain every input and output from all of the PSBTs. Any signatures
222  provided in any of the PSBTs will be dropped.
223
224- `analyzepsbt` examines a PSBT and provides information about what
225  the PSBT contains and the next steps that need to be taken in order
226  to complete the transaction. For each input of a PSBT, `analyzepsbt`
227  provides information about what information is missing for that
228  input, including whether a UTXO needs to be provided, what pubkeys
229  still need to be provided, which scripts need to be provided, and
230  what signatures are still needed. Every input will also list which
231  role is needed to complete that input, and `analyzepsbt` will also
232  list the next role in general needed to complete the PSBT.
233  `analyzepsbt` will also provide the estimated fee rate and estimated
234  virtual size of the completed transaction if it has enough
235  information to do so.
236
237- `utxoupdatepsbt` searches the set of Unspent Transaction Outputs
238  (UTXOs) to find the outputs being spent by the partial transaction.
239  PSBTs need to have the UTXOs being spent to be provided because
240  the signing algorithm requires information from the UTXO being spent.
241  For segwit inputs, only the UTXO itself is necessary.  For
242  non-segwit outputs, the entire previous transaction is needed so
243  that signers can be sure that they are signing the correct thing.
244  Unfortunately, because the UTXO set only contains UTXOs and not full
245  transactions, `utxoupdatepsbt` will only add the UTXO for segwit
246  inputs.
247
248Updated RPCs
249------------
250

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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