9ec75c5 Add a locking mechanism to IsInitialBlockDownload to ensure it never goes from false to true. (Ruben Dario Ponticelli)
a2d0fc6 Fix IsInitialBlockDownload which was broken by headers first. (Ruben Dario Ponticelli)
There are 3 pieces of data that are maintained on disk. The actual block
and undo data, the block index (which can refer to positions on disk),
and the chainstate (which refers to the best block hash).
Earlier, there was no guarantee that blocks were written to disk before
block index entries referring to them were written. This commit introduces
dirty flags for block index data, and delays writing entries until the actual
block data is flushed.
With this stricter ordering in writes, it is now safe to not always flush
after every block, so there is no need for the IsInitialBlockDownload()
check there - instead we just write whenever enough time has passed or
the cache size grows too large. Also updating the wallet's best known block
is delayed until this is done, otherwise the wallet may end up referring to an
unknown block.
In addition, only do a write inside the block processing loop if necessary
(because of cache size exceeded). Otherwise, move the writing to a point
after processing is done, after relaying.
Like in a real world situation, a safe mode test should also be visible in the
UI. A test of safe mode is furthermore mostly relevant for developers, so it
should not be overwritten by a warning about a pre-release test build.
Previously, AcceptBlockHeader did not check the header (in particular
PoW). This made the client accept invalid-PoW-headers from peers in
headers-first sync.
Previously transactions were only tested again the
STANDARD_SCRIPT_VERIFY_FLAGS prior to mempool acceptance, so any bugs in
those flags that allowed actually-invalid transactions to pass would
result in allowing invalid transactions into the mempool. Fortunately
there is a second check in CreateNewBlock() that would prevent those
transactions from being mined, resulting in an invalid block, however
this could still be exploited as a DoS attack.
This is a simplified re-do of closed pull #3088.
This patch eliminates the privacy and reliability problematic use
of centralized web services for discovering the node's addresses
for advertisement.
The Bitcoin protocol already allows your peers to tell you what
IP they think you have, but this data isn't trustworthy since
they could lie. So the challenge is using it without creating a
DOS vector.
To accomplish this we adopt an approach similar to the one used
by P2Pool: If we're announcing and don't have a better address
discovered (e.g. via UPNP) or configured we just announce to
each peer the address that peer told us. Since peers could
already replace, forge, or drop our address messages this cannot
create a new vulnerability... but if even one of our peers is
giving us a good address we'll eventually make a useful
advertisement.
We also may randomly use the peer-provided address for the
daily rebroadcast even if we otherwise have a seemingly routable
address, just in case we've been misconfigured (e.g. by UPNP).
To avoid privacy problems, we only do these things if discovery
is enabled.
50b43fd Be a bit more verbose during -loadblock if we already have blocks (Matt Corallo)
8375e22 Fix -loadblock after shutdown during IBD (Matt Corallo)
4ead850 Fix for crash during block download (Matt Corallo)
1bea2bb Rename ProcessBlock to ProcessNewBlock to indicate change of behaviour, and document it (Luke Dashjr)
d29a291 Rename RPC_TRANSACTION_* errors to RPC_VERIFY_* and use RPC_VERIFY_ERROR for submitblock (Luke Dashjr)
f877aaa Bugfix: submitblock: Use a temporary CValidationState to determine accurately the outcome of ProcessBlock, now that it no longer does the full block validity check (Luke Dashjr)
24e8896 Add CValidationInterface::BlockChecked notification (Luke Dashjr)
a873823 CAutoFile: Explicit Get() and remove unused methods (Wladimir J. van der Laan)
fef24ca Add IsNull() to class CAutoFile and remove operator ! (Ruben Dario Ponticeli)
Previous refactorings broke the ability to rebuild the chainstate by deleting the chainstate
directory, resulting in an incorrect "Incorrect or no genesis block found" error message. Fix
that.
Also, improve the performance of ActivateBestBlockStep by using the skiplist to only discover
a few potential blocks to connect at a time, instead of all blocks forever - as we likely bail
out after connecting a single one anyway.
Instead of skipping to the last reindexed block in each file (which could
jump over processed out-of-order blocks), just skip each already processed
block individually.
Remember out-of-order block headers along with disk positions. This is
likely the simplest and least-impact way to make -reindex work with
headers first.
Based on top of #4468.
Many changes:
* Do not use 'getblocks', but 'getheaders', and use it to build a headers tree.
* Blocks are fetched in parallel from all available outbound peers, using a
limited moving window. When one peer stalls the movement of the window, it is
disconnected.
* No more orphan blocks. At all. We only ever request a block for which we have
verified the headers, and store it to disk immediately. This means that a
disk-fill attack would require PoW.
* Require protocol version 31800 for every peer (released in december 2010).
* No more syncnode (we sync from everyone we can, though limited to 1 during
initial *headers* sync).
* Introduce some extra named constants, comments and asserts.
This adds a -regetest-only undocumented (for regression testing only)
command-line option -blockversion=N to set block.nVersion.
Adds to the "has the rest of the network upgraded to a
block.nVersion we don't understand" code so it calls
-alertnotify when 51 of the last 100 blocks are up-version.
But it only alerts once, not with every subsequent new, upversion
block.
And adds a forknotify.py regression test to make sure it works.
Tested using forknotify.py:
Before adding CAlert::Notify, get:
Assertion failed: -alertnotify did not warn of up-version blocks
Before adding code to only alert once:
Assertion failed: -alertnotify excessive warning of up-version blocks
After final code in this pull:
Tests successful
7c70438 Get rid of the dummy CCoinsViewCache constructor arg (Pieter Wuille)
ed27e53 Add coins_tests with a large randomized CCoinViewCache test. (Pieter Wuille)
058b08c Do not keep fully spent but unwritten CCoins entries cached. (Pieter Wuille)
c9d1a81 Get rid of CCoinsView's SetCoins and SetBestBlock. (Pieter Wuille)
f28aec0 Use ModifyCoins instead of mutable GetCoins. (Pieter Wuille)
e790c37 Replace SCRIPT_VERIFY_NOCACHE by flag directly to checker (Pieter Wuille)
5c1e798 Make signature cache optional (Pieter Wuille)
c7829ea Abstract out SignatureChecker (Pieter Wuille)
938bcce CAutoFile: make file private (Philip Kaufmann)
0c35486 CBufferedFile: add explicit close function (Philip Kaufmann)
c9fb27d CBufferedFile: convert into a non-refcounted RAII wrapper (Philip Kaufmann)
There is only one message passed to AbortNode() that makes sense to
translate to the user specifically: Disk space is low. For the others
show a generic message and refer to debug.log for details.
Reduces the number of confusing jargon translation messages.
- it now takes over the passed file descriptor and closes it in the
destructor
- this fixes a leak in LoadExternalBlockFile(), where an exception could
cause the file to not getting closed
- disallow copies (like recently added for CAutoFile)
- make nType and nVersion private
4705902 Avoid introducing a virtual into CChainParams (Wladimir J. van der Laan)
5e2e7fc Suggested corrections on comments, variable names. Also new test case testing the PoW skip in UNITTEST. (SergioDemianLerner)
a25fd6b Switch testing framework from MAIN to new UNITTEST network (SergioDemianLerner)
f74fc9b Print input index when signature validation fails, to aid debugging. (Mark Friedenbach)
217a5c9 When transaction outputs exceed inputs, show the offending amounts so as to aid debugging. (Mark Friedenbach)
Move the txid duplicates check into BuildMerkleTree, where it can be done
much more efficiently (without needing to build a full txid set to detect
duplicates).
The previous version (using the std::set<uint256> to detect duplicates) was
also slightly too weak. A block mined with actual duplicate transactions
(which is invalid, due to the inputs of the duplicated transactions being
seen as double spends) would trigger the duplicates logic, resulting in the
block not being stored on disk, and rerequested. This change fixes that by
only triggering in the case of duplicated transactions that can actually
result in an identical merkle root.
Instead of storing CCoins entries directly in CCoinsMap, store a CCoinsCacheEntry
which additionally keeps track of whether a particular entry is:
* dirty: potentially different from its parent view.
* fresh: the parent view is known to not have a non-pruned version.
This allows us to skip non-dirty cache entries when pushing batches of changes up,
and to remove CCoins entries about transactions that are fully spent before the
parent cache learns about them.
All direct modifications are now done through ModifyCoins, and BatchWrite is
used for pushing batches of queued modifications up, so we don't need the
low-level SetCoins and SetBestBlock anymore in the top-level CCoinsView class.
Replace the mutable non-copying GetCoins method with a ModifyCoins, which
returns an encapsulated iterator, so we can keep track of concurrent
modifications (as iterators can be invalidated by those) and run cleanup
code after a modification is finished.
This also removes the overloading of the 'GetCoins' name.
There is no reason to store thousands of orphan transactions;
normally an orphan's parents will either be broadcast or
mined reasonably quickly.
This pull drops the maximum number of orphans from 10,000 down
to 100, and adds a command-line option (-maxorphantx) that is
just like -maxorphanblocks to override the default.
Prevent denial-of-service attacks by banning
peers that send us invalid orphan transactions
and only storing orphan transactions given to
us by a peer while the peer is connected.
2c2cc5d Remove some unnecessary c_strs() in logging and the GUI (Philip Kaufmann)
f7d0a86 netbase: Use .data() instead of .c_str() on binary string (Wladimir J. van der Laan)
The efficient version of CCoinsViewCache::GetCoins only works for known-to-exist
cache entries, requiring a separate HaveCoins call beforehand. This is
inefficient as both perform a hashtable lookup.
Replace the non-mutable GetCoins with AccessCoins, which returns a potentially-NULL
pointer. This also decreases the overloading of GetCoins.
Also replace some copying (inefficient) GetCoins calls with equivalent AccessCoins,
decreasing the copying.
Bypassing the main coins cache allows more thorough checking with the same
memory budget.
This has no effect on performance because everything ends up in the child
cache created by VerifyDB itself.
It has bugged me ever since #4675, which effectively reduced the
number of checked blocks to reduce peak memory usage.
- Pass the coinsview to use as argument to VerifyDB
- This also avoids that the first `pcoinsTip->Flush()` after VerifyDB
writes a large slew of unchanged coin records back to the database.
ad49c25 Split up util.cpp/h (Wladimir J. van der Laan)
f841aa2 Move `COIN` and `CENT` to core.h (Wladimir J. van der Laan)
6e5fd00 Move `*Version()` functions to version.h/cpp (Wladimir J. van der Laan)
b4aa769 Move `S_I*` constants and `MSG_NOSIGNAL` to compat.h (Wladimir J. van der Laan)
af8297c Move functions in wallet.h to implementation file (Wladimir J. van der Laan)
651480c move functions in main and net to implementation files (Wladimir J. van der Laan)
610a8c0 Move SetThreadPriority implementation to util.cpp instead of the header (Wladimir J. van der Laan)
f780e65 Remove unused function `ByteReverse` from util.h (Wladimir J. van der Laan)
121d6ad Remove unused `alignup` function from util.h (Wladimir J. van der Laan)
d1e26d4 Move CMedianFilter to timedata.cpp (Wladimir J. van der Laan)
Split up util.cpp/h into:
- string utilities (hex, base32, base64): no internal dependencies, no dependency on boost (apart from foreach)
- money utilities (parsesmoney, formatmoney)
- time utilities (gettime*, sleep, format date):
- and the rest (logging, argument parsing, config file parsing)
The latter is basically the environment and OS handling,
and is stripped of all utility functions, so we may want to
rename it to something else than util.cpp/h for clarity (Matt suggested
osinterface).
Breaks dependency of sha256.cpp on all the things pulled in by util.
Due to growing coinsviewcaches, the memory usage with checklevel=3
(and standard settings for dbcache) could be up to 500MiB on a
64-bit system. This is about twice the peak during reindexing,
unnecessarily extending bitcoind's memory envelope.
This commit reduces the maximum total size of the caches used during
verification to just nCoinCacheSize, which should be the limit.
Remove the 'state' and 'exceptmask' from serialize.h's stream implementations,
as well as related methods.
As exceptmask always included 'failbit', and setstate was always called with
bits = failbit, all it did was immediately raise an exception. Get rid of
those variables, and replace the setstate with direct exception throwing
(which also removes some dead code).
As a result, good() is never reached after a failure (there are only 2
calls, one of which is in tests), and can just be replaced by !eof().
fail(), clear(n) and exceptions() are just never called. Delete them.
The only other method of logging remote addresses is via
-logips=1 -debug=net
which increases the logged activity by 100x or more.
Github-Pull: #4608
Amended-By: Wladimir J. van der Laan <laanwj@gmail.com>
Port over https://github.com/chronokings/huntercoin/pull/19 from
Huntercoin: This implements a new RPC command "getchaintips" that can be
used to find all currently active chain heads. This is similar to the
-printblocktree startup option, but it can be used without restarting
just via the RPC interface on a running daemon.
* Replace -benchmark (and the related fBenchmark) with a regular debug option, -debug=bench.
* Increase coverage and granularity of individual block processing steps.
* Add cummulative times.
First and foremost, this defaults to OFF.
This option lets a node consider such transactions non-standard,
meaning they will not be relayed or mined by default, but other miners
are free to mine these as usual.
4eedf4f make RandAddSeed() use OPENSSL_cleanse() (Philip Kaufmann)
6354935 move rand functions from util to new random.h/.cpp (Philip Kaufmann)
001a53d add GetRandBytes() as wrapper for RAND_bytes() (Philip Kaufmann)
This adds a -whitelist option to specify subnet ranges from which peers
that connect are whitelisted. In addition, there is a -whitebind option
which works like -bind, except peers connecting to it are also
whitelisted (allowing a separate listen port for trusted connections).
Being whitelisted has two effects (for now):
* They are immune to DoS disconnection/banning.
* Transactions they broadcast (which are valid) are always relayed,
even if they were already in the mempool. This means that a node
can function as a gateway for a local network, and that rebroadcasts
from the local network will work as expected.
Whitelisting replaces the magic exemption localhost had for DoS
disconnection (local addresses are still never banned, though), which
implied hidden service connects (from a localhost Tor node) were
incorrectly immune to DoS disconnection as well. This old
behaviour is removed for that reason, but can be restored using
-whitelist=127.0.0.1 or -whitelist=::1 can be specified. -whitebind
is safer to use in case non-trusted localhost connections are expected
(like hidden services).
- add a small wrapper in util around RAND_bytes() and replace with
GetRandBytes() in the code to log errors from calling RAND_bytes()
- remove OpenSSL header rand.h where no longer needed
75f51f2a introduced asynchronous processing for blocks, where reject messages
and DoS scoring could be applied outside of ProcessBlock, because block
validation may happen later.
However, some types of errors are still detected immediately (in particular,
CheckBlock violations), which need acting after ProcessBlock returns.
The wallet now uses the mempool fee estimator with a new
command-line option: -txconfirmtarget (default: 1) instead
of using hard-coded fees or priorities.
A new bitcoind that hasn't seen enough transactions to estimate
will fall back to the old hard-coded minimum priority or
transaction fee.
-paytxfee option overrides -txconfirmtarget.
Relaying and mining code isn't changed.
For Qt, the coin control dialog now uses priority estimates to
label transaction priority (instead of hard-coded constants);
unspent outputs were consistently labeled with a much higher
priority than is justified by the free transactions actually
being accepted into blocks.
I did not implement any GUI for setting -txconfirmtarget; I would
suggest getting rid of the "Pay transaction fee" GUI and replace
it with either "target number of confirmations" or maybe
a "faster confirmation <--> lower fee" slider or select box.
The original comment forgets to account for the script push which will
need an OP_PUSHDATA2 + 2-bytes for the 513 script bytes.
props davecgh
fixes#4224
Allows network wallets and other clients to see transactions that respend
a prevout already spent in an unconfirmed transaction in this node's mempool.
Knowledge of an attempted double-spend is of interest to recipients of the
first spend. In some cases, it will allow these recipients to withhold
goods or services upon being alerted of a double-spend that deprives them
of payment.
As before, respends are not added to the mempool.
Anti-Denial-of-Service-Attack provisions:
- Use a bloom filter to relay only one respend per mempool prevout
- Rate-limit respend relays to a default of 100 thousand bytes/minute
- Define tx2.IsEquivalentTo(tx1): equality when scriptSigs are not considered
- Do not relay these equivalent transactions
Remove an unused variable declaration in txmempool.cpp.
Relax the AreInputsStandard() tests for P2SH transactions --
allow any Script in a P2SH transaction to be relayed/mined,
as long as it has 15 or fewer signature operations.
Rationale: https://gist.github.com/gavinandresen/88be40c141bc67acb247
I don't have an easy way to test this, but the code changes are
straightforward and I've updated the AreInputsStandard unit tests.
