Use object returned from add_p2p_connection to refer to
p2ps. Add a test class attribute if it needs to be used across
many methods. Don't use the p2p property.
substitutes "for x in range(N):" by "for _ in range(N):"
indicates to the reader that a block is just repeated N times, and
that the loop counter is not used in the body
7a6627ae87 Fix mining to an invalid target + ensure that a new block has the correct hash internally in Python tests (Samer Afach)
Pull request description:
Test with block 47 in the `feature_block.py` creates a block with a hash higher than the target, which is supposed to fail. Now two issues exist there, and both have low probability of showing up:
1. The creation is done with `while (hash < target)`, which is wrong, because hash = target is a valid mined value based on the code in the function `CheckProofOfWork()` that validates the mining target:
```
if (UintToArith256(hash) > bnTarget)
return false;
```
2. As we know the hash stored in CBlock class in Python is stateful, unlike how it's in C++, where calling `CBlock::GetHash()` will actively calculate the hash and not cache it anywhere. With this, blocks that come out of the method `next_block` can have incorrect hash value when `solve=False`. This is because the `next_block` is mostly used with `solve=True`, and solving does call the function `rehash()` which calculates the hash of the block, but with `solve=False`, nothing calls that method. And since the work to be done in regtests is very low, the probably of this problem showing up is very low, but it practically happens (well, with much higher probability compared to issue No. 1 above).
This PR fixes both these issues.
Top commit has no ACKs.
Tree-SHA512: f3b54d18f5073d6f1c26eab89bfec78620dda4ac1e4dde4f1d69543f1b85a7989d64c907e091db63f3f062408f5ed1e111018b842819ba1a5f8348c7b01ade96
The function implementing segwit v0 signature hash was originally named
SegwitVersion1SignatureHash() (presumably before segwit v0 was named
segwit v0). Rename it to SegwitV0SignatureHash().
Also rename SignatureHash() to LegacySignatureHash() for disambiguation.
0c62e3aa73 New regression testing for CVE-2018-17144, CVE-2012-2459, and CVE-2010-5137. (lucash-dev)
38bfca6bb2 Added comments referencing multiple CVEs in tests and production code. (lucash-dev)
Pull request description:
This functional test includes two scenarios that test for regressions of vulnerabilities, but they are only briefly described. There are freely available documents explaining in detail the issues, but without explicit mentions, the developer trying to maintain the code needs an additional step of digging in commit history and PR conversations to figure it out.
Added comments to explicitly mention CVE-2018-17144 and CVE-2012-2459, for more complete documentation.
This improves developer experience by making understanding the tests easier.
ACKs for top commit:
laanwj:
ACK 0c62e3aa73, checked the CVE numbers, thanks for adding documentation
Tree-SHA512: 3ee05351745193b8b959e4a25d50f25a693b2d24b0732ed53cf7d5882df40b5dd0f1877bd5c69cffb921d4a7acf9deb3cc1160b96dc730d9b5984151ad06b7c9
fa8489a155 test: Add test for BIP30 duplicate tx (MarcoFalke)
77770d95e2 test: Properly serialize BIP34 coinbase height (MarcoFalke)
Pull request description:
This adds a test for BIP30 to check that duplicate txs can exist in the blockchain given the first one was completely spent when the second one is added. (Requested by ajtowns in https://github.com/bitcoin/bitcoin/pull/16333#issuecomment-508604071)
We can not add a test that a later duplicate tx overwrites a previous one, because BIP30 is always enforced on regtest. If someone feels strongly about such a test, some Bitcoin Core code would have to be modified, which can be done in a follow up pull request.
Also, add a commit to fix the BIP34 test failures reported in https://github.com/bitcoin/bitcoin/pull/14633#issue-227712540
ACKs for top commit:
laanwj:
Code review ACK fa8489a155
Tree-SHA512: c707d0bdc93937263876b603425b53322a2a9f9ec3f50716ae2fa9de8ddc644beb22b26c1bfde7f4aab102633e096b354ef380db919176bd2cb44a2828f884aa
This commit adds comments referencing multiple CVEs both in production and test code.
CVEs covered in this commit:
CVE-2010-5137
CVE-2010-5139
CVE-2010-5141
CVE-2012-1909
CVE-2012-2459
CVE-2012-3789
CVE-2018-17144
0ff1c2a838 Separate reason for premature spends (coinbase/locktime) (Suhas Daftuar)
54470e767b Assert validation reasons are contextually correct (Suhas Daftuar)
2120c31521 [refactor] Update some comments in validation.cpp as we arent doing DoS there (Matt Corallo)
12dbdd7a41 [refactor] Drop unused state.DoS(), state.GetDoS(), state.CorruptionPossible() (Matt Corallo)
aa502b88d1 scripted-diff: Remove DoS calls to CValidationState (Matt Corallo)
7721ad64f4 [refactor] Prep for scripted-diff by removing some \ns which annoy sed. (Matt Corallo)
5e78c5734b Allow use of state.Invalid() for all reasons (Matt Corallo)
6b34bc6b6f Fix handling of invalid headers (Suhas Daftuar)
ef54b486d5 [refactor] Use Reasons directly instead of DoS codes (Matt Corallo)
9ab2a0412e CorruptionPossible -> BLOCK_MUTATED (Matt Corallo)
6e55b292b0 CorruptionPossible -> TX_WITNESS_MUTATED (Matt Corallo)
7df16e70e6 LookupBlockIndex -> CACHED_INVALID (Matt Corallo)
c8b0d22698 [refactor] Drop redundant nDoS, corruptionPossible, SetCorruptionPossible (Matt Corallo)
34477ccd39 [refactor] Add useful-for-dos "reason" field to CValidationState (Matt Corallo)
6a7f8777a0 Ban all peers for all block script failures (Suhas Daftuar)
7b999103e2 Clean up banning levels (Matt Corallo)
b8b4c80146 [refactor] drop IsInvalid(nDoSOut) (Matt Corallo)
8818729013 [refactor] Refactor misbehavior ban decisions to MaybePunishNode() (Matt Corallo)
00e11e61c0 [refactor] rename stateDummy -> orphan_state (Matt Corallo)
f34fa719cf Drop obsolete sigops comment (Matt Corallo)
Pull request description:
This is a rebase of #11639 with some fixes for the last few comments which were not yet addressed.
The original PR text, with some strikethroughs of text that is no longer correct:
> This cleans up an old main-carryover - it made sense that main could decide what DoS scores to assign things because the DoS scores were handled in a different part of main, but now validation is telling net_processing what DoS scores to assign to different things, which is utter nonsense. Instead, we replace CValidationState's nDoS and CorruptionPossible with a general ValidationInvalidReason, which net_processing can handle as it sees fit. I keep the behavior changes here to a minimum, but in the future we can utilize these changes for other smarter behavior, such as disconnecting/preferring to rotate outbound peers based on them providing things which are invalid due to SOFT_FORK because we shouldn't ban for such cases.
>
> This is somewhat complementary with, though obviously conflicts heavily with #11523, which added enums in place of DoS scores, as well as a few other cleanups (which are still relevant).
>
> Compared with previous bans, the following changes are made:
>
> Txn with empty vin/vout or null prevouts move from 10 DoS
> points to 100.
> Loose transactions with a dependency loop now result in a ban
> instead of 10 DoS points.
> ~~BIP68-violation no longer results in a ban as it is SOFT_FORK.~~
> ~~Non-SegWit SigOp violation no longer results in a ban as it
> considers P2SH sigops and is thus SOFT_FORK.~~
> ~~Any script violation in a block no longer results in a ban as
> it may be the result of a SOFT_FORK. This should likely be
> fixed in the future by differentiating between them.~~
> Proof of work failure moves from 50 DoS points to a ban.
> Blocks with timestamps under MTP now result in a ban, blocks
> too far in the future continue to not result in a ban.
> Inclusion of non-final transactions in a block now results in a
> ban instead of 10 DoS points.
Note: The change to ban all peers for consensus violations is actually NOT the change I'd like to make -- I'd prefer to only ban outbound peers in those situations. The current behavior is a bit of a mess, however, and so in the interests of advancing this PR I tried to keep the changes to a minimum. I plan to revisit the behavior in a followup PR.
EDIT: One reviewer suggested I add some additional context for this PR:
> The goal of this work was to make net_processing aware of the actual reasons for validation failures, rather than just deal with opaque numbers instructing it to do something.
>
> In the future, I'd like to make it so that we use more context to decide how to punish a peer. One example is to differentiate inbound and outbound peer misbehaviors. Another potential example is if we'd treat RECENT_CONSENSUS_CHANGE failures differently (ie after the next consensus change is implemented), and perhaps again we'd want to treat some peers differently than others.
ACKs for commit 0ff1c2:
jnewbery:
utACK 0ff1c2a838
ryanofsky:
utACK 0ff1c2a838. Only change is dropping the first commit (f3883a321bf4ab289edcd9754b12cae3a648b175), and dropping the temporary `assert(level == GetDoS())` that was in 35ee77f2832eaffce30042e00785c310c5540cdc (now c8b0d22698)
Tree-SHA512: e915a411100876398af5463d0a885920e44d473467bb6af991ef2e8f2681db6c1209bb60f848bd154be72d460f039b5653df20a6840352c5f7ea5486d9f777a3
This is a first step towards cleaning up our DoS interface - make
validation return *why* something is invalid, and let net_processing
figure out what that implies in terms of banning/disconnection/etc.
Behavior change: peers will now be banned for providing blocks
with premature coinbase spends.
Co-authored-by: Anthony Towns <aj@erisian.com.au>
Suhas Daftuar <sdaftuar@gmail.com>
Compared with previous bans, the following changes are made:
* Txn with empty vin/vout or null prevouts move from 10 DoS
points to 100.
* Loose transactions with a dependency loop now result in a ban
instead of 10 DoS points.
* Many pre-segwit soft-fork errors now result in a ban.
Note: Transactions that violate soft-fork script flags since P2SH do not generally
result in a ban. Also, banning behavior for invalid blocks is dependent on
whether the node is validating with multiple script check threads, due to a long-
standing bug. That inconsistency is still present after this commit.
* Proof of work failure moves from 50 DoS points to a ban.
* Blocks with timestamps under MTP now result in a ban, blocks
too far in the future continue to *not* result in a ban.
* Inclusion of non-final transactions in a block now results in a
ban instead of 10 DoS points.
Co-authored-by: Anthony Towns <aj@erisian.com.au>
