fb3e812277 p2p: return `CSubNet` in `LookupSubNet` (brunoerg)
Pull request description:
Analyzing the usage of `LookupSubNet`, noticed that most cases uses check if the subnet is valid by calling `subnet.IsValid()`, and the boolean returned by `LookupSubNet` hasn't been used so much, see:
29d540b7ad/src/httpserver.cpp (L172-L174)29d540b7ad/src/net_permissions.cpp (L114-L116)
It makes sense to return `CSubNet` instead of `bool`.
ACKs for top commit:
achow101:
ACK fb3e812277
vasild:
ACK fb3e812277
theStack:
Code-review ACK fb3e812277
stickies-v:
Concept ACK, but Approach ~0 (for now). Reviewed the code (fb3e812277) and it all looks good to me.
Tree-SHA512: ba50d6bd5d58dfdbe1ce1faebd80dd8cf8c92ac53ef33519860b83399afffab482d5658cb6921b849d7a3df6d5cea911412850e08f3f4e27f7af510fbde4b254
0e6f6ebc06 net: remove unused CConnman::FindNode(const CSubNet&) (Vasil Dimov)
9482cb780f netbase: possibly change the result of LookupSubNet() to CJDNS (Vasil Dimov)
53afa68026 net: move MaybeFlipIPv6toCJDNS() from net to netbase (Vasil Dimov)
6e308651c4 net: move IsReachable() code to netbase and encapsulate it (Vasil Dimov)
c42ded3d9b fuzz: ConsumeNetAddr(): avoid IPv6 addresses that look like CJDNS (Vasil Dimov)
64d6f77907 net: put CJDNS prefix byte in a constant (Vasil Dimov)
Pull request description:
`LookupSubNet()` would treat addresses that start with `fc` as IPv6 even if `-cjdnsreachable` is set. This creates the following problems where it is called:
* `NetWhitelistPermissions::TryParse()`: otherwise `-whitelist=` fails to white list CJDNS addresses: when a CJDNS peer connects to us, it will be matched against IPv6 `fc...` subnet and the match will never succeed.
* `BanMapFromJson()`: CJDNS bans are stored as just IPv6 addresses in `banlist.json`. Upon reading from disk they have to be converted back to CJDNS, otherwise, after restart, a ban entry like (`fc00::1`, IPv6) would not match a peer (`fc00::1`, CJDNS).
* `RPCConsole::unbanSelectedNode()`: in the GUI the ban entries go through `CSubNet::ToString()` and back via `LookupSubNet()`. Then it must match whatever is stored in `BanMan`, otherwise it is impossible to unban via the GUI.
These were uncovered by https://github.com/bitcoin/bitcoin/pull/26859.
Thus, flip the result of `LookupSubNet()` to CJDNS if the network base address starts with `fc` and `-cjdnsreachable` is set. Since subnetting/masking does not make sense for CJDNS (the address is "random" bytes, like Tor and I2P, there is no hierarchy) treat `fc.../mask` as an invalid `CSubNet`.
To achieve that, `MaybeFlipIPv6toCJDNS()` has to be moved from `net` to `netbase` and thus also `IsReachable()`. In the process of moving `IsReachable()`, `SetReachable()` and `vfLimited[]` encapsulate those in a class.
ACKs for top commit:
jonatack:
Code review ACK 0e6f6ebc06
achow101:
ACK 0e6f6ebc06
mzumsande:
re-ACK 0e6f6ebc06
Tree-SHA512: 4767a60dc882916de4c8b110ce8de208ff3f58daaa0b560e6547d72e604d07c4157e72cf98b237228310fc05c0a3922f446674492e2ba02e990a272d288bd566
9620cb4493 assumeutxo: fail early if snapshot block hash doesn't match AssumeUTXO parameters (Sebastian Falbesoner)
Pull request description:
Right now the `loadtxoutset` RPC call treats literally all files with a minimum size of 40 bytes (=size of metadata) as potential valid snapshot candidates and the waiting loop for seeing the metadata block hash in the headers chain is always entered, e.g.:
```
$ ./src/bitcoin-cli loadtxoutset ~/.vimrc
<wait>
bitcoind log:
...
2023-10-15T14:55:45Z [snapshot] waiting to see blockheader 626174207465730a7265626d756e207465730a656c62616e65207861746e7973 in headers chain before snapshot activation
...
```
There is no point in doing any further action though if we already know from the start that the UTXO snapshot loading won't be successful. This PR adds an assumeutxo parameter check immediately after the metadata is read in, so we can fail immediately on a mismatch:
```
$ ./src/bitcoin-cli loadtxoutset ~/.vimrc
error code: -32603
error message:
Unable to load UTXO snapshot, assumeutxo block hash in snapshot metadata not recognized (626174207465730a7265626d756e207465730a656c62616e
65207861746e7973)
```
This way, users who mistakenly try to load files that are not snapshots don't have to wait 10 minutes (=the block header waiting timeout) anymore to get a negative response. If a file is loaded which is a valid snapshot (referencing to an existing block hash), but one which doesn't match the parameters, the feedback is also faster, as we don't have to wait anymore to see the hash in the headers chain before getting an error.
This is also partially fixes #28621.
ACKs for top commit:
maflcko:
lgtm ACK 9620cb4493
ryanofsky:
Code review ACK 9620cb4493. This should fix an annoyance and bad UX.
pablomartin4btc:
tACK 9620cb4493
Tree-SHA512: f88b865e9d46254858e57c024463f389cd9d8760a7cb30c190aa1723a931e159987dfc2263a733825d700fa612e7416691e4d8aab64058f1aeb0a7fa9233ac9c
fa05a726c2 tidy: modernize-use-emplace (MarcoFalke)
Pull request description:
Constructing a temporary unnamed object only to copy or move it into a container seems both verbose in code and a strict performance penalty.
Fix both issues via the `modernize-use-emplace` tidy check.
ACKs for top commit:
Sjors:
re-utACK fa05a726c2
hebasto:
ACK fa05a726c2.
TheCharlatan:
ACK fa05a726c2
Tree-SHA512: 4408a094f406e7bf6c1468c2b0798f68f4d952a1253cf5b20bdc648ad7eea4a2c070051fed46d66fd37bce2ce6f85962484a1d32826b7ab8c9baba431eaa2765
All callers of `LookupSubNet()` need the result to be of CJDNS type if
`-cjdnsreachable` is set and the address begins with `fc`:
* `NetWhitelistPermissions::TryParse()`: otherwise `-whitelist=` fails
to white list CJDNS addresses: when a CJDNS peer connects to us, it
will be matched against IPv6 `fc...` subnet and the match will never
succeed.
* `BanMapFromJson()`: CJDNS bans are stored as just IPv6 addresses in
`banlist.json`. Upon reading from disk they have to be converted back
to CJDNS, otherwise, after restart, a ban entry like (`fc00::1`, IPv6)
would not match a peer (`fc00::1`, CJDNS).
* `setban()` (in `rpc/net.cpp`): otherwise `setban fc.../mask add` would
add an IPv6 entry to BanMan. Subnetting does not make sense for CJDNS
addresses, thus treat `fc.../mask` as invalid `CSubNet`. The result of
`LookupHost()` has to be converted for the case of banning a single
host.
* `InitHTTPAllowList()`: not necessary since before this change
`-rpcallowip=fc...` would match IPv6 subnets against IPv6 peers even
if they started with `fc`. But because it is necessary for the above,
`HTTPRequest::GetPeer()` also has to be adjusted to return CJDNS peer,
so that now CJDNS peers are matched against CJDNS subnets.
5b878be742 [doc] add release note for submitpackage (glozow)
7a9bb2a2a5 [rpc] allow submitpackage to be called outside of regtest (glozow)
5b9087a9a7 [rpc] require package to be a tree in submitpackage (glozow)
e32ba1599c [txpackages] IsChildWithParentsTree() (glozow)
b4f28cc345 [doc] parent pay for child in aggregate CheckFeeRate (glozow)
Pull request description:
Permit (restricted topology) submitpackage RPC outside of regtest. Suggested in https://github.com/bitcoin/bitcoin/pull/26933#issuecomment-1510851570
This RPC should be safe but still experimental - interface may change, not all features (e.g. package RBF) are implemented, etc. If a miner wants to expose this to people, they can effectively use "package relay" before the p2p changes are implemented. However, please note **this is not package relay**; transactions submitted this way will not relay to other nodes if the feerates are below their mempool min fee. Users should put this behind some kind of rate limit or permissions.
ACKs for top commit:
instagibbs:
ACK 5b878be742
achow101:
ACK 5b878be742
dergoegge:
Code review ACK 5b878be742
ajtowns:
ACK 5b878be742
ariard:
Code Review ACK 5b878be742. Though didn’t manually test the PR.
Tree-SHA512: 610365c0b2ffcccd55dedd1151879c82de1027e3319712bcb11d54f2467afaae4d05dca5f4b25f03354c80845fef538d3938b958174dda8b14c10670537a6524
Current getchainstates RPC returns "normal" and "snapshot" fields which are not
ideal because it requires new "normal" and "snapshot" terms to be defined, and
the definitions are not really consistent with internal code. (In the RPC
interface, the "snapshot" chainstate becomes the "normal" chainstate after it
is validated, while in internal code there is no "normal chainstate" and the
"snapshot chainstate" is still called that temporarily after it is validated).
The current getchainstatees RPC is also awkward to use if you to want
information about the most-work chainstate because you have to look at the
"snapshot" field if it exists, and otherwise fall back to the "normal" field.
Fix these issues by having getchainstates just return a flat list of
chainstates ordered by work, and adding new chainstate "validated" field
alongside the existing "snapshot_blockhash" so it is explicit if a chainstate
was originally loaded from a snapshot, and whether the snapshot has been
validated.
`vfLimited`, `IsReachable()`, `SetReachable()` need not be in the `net`
module. Move them to `netbase` because they will be needed in
`LookupSubNet()` to possibly flip the result to CJDNS (if that network
is reachable).
In the process, encapsulate them in a class.
`NET_UNROUTABLE` and `NET_INTERNAL` are no longer ignored when adding
or removing reachable networks. This was unnecessary.
- make `getaddrmaninfo` RPC public since it's not for development
purposes only and regular users might find it useful
- add missing `all_networks` key to RPC help
- use clang format spacing
352d5eb2a9 test: getrawaddrman RPC (0xb10c)
da384a286b rpc: getrawaddrman for addrman entries (0xb10c)
Pull request description:
Inspired by `getaddrmaninfo` (#27511), this adds a hidden/test-only `getrawaddrman` RPC. The RPC returns information on all addresses in the address manager new and tried tables. Addrman table contents can be used in tests and during development.
The RPC result encodes the `bucket` and `position`, the internal location of addresses in the tables, in the address object's string key. This allows users to choose to consume or to ignore the location information. If the internals of the address manager implementation change, the location encoding might change too.
```
getrawaddrman
EXPERIMENTAL warning: this call may be changed in future releases.
Returns information on all address manager entries for the new and tried tables.
Result:
{ (json object)
"table" : { (json object) buckets with addresses in the address manager table ( new, tried )
"bucket/position" : { (json object) the location in the address manager table (<bucket>/<position>)
"address" : "str", (string) The address of the node
"port" : n, (numeric) The port number of the node
"network" : "str", (string) The network (ipv4, ipv6, onion, i2p, cjdns) of the address
"services" : n, (numeric) The services offered by the node
"time" : xxx, (numeric) The UNIX epoch time when the node was last seen
"source" : "str", (string) The address that relayed the address to us
"source_network" : "str" (string) The network (ipv4, ipv6, onion, i2p, cjdns) of the source address
},
...
},
...
}
Examples:
> bitcoin-cli getrawaddrman
> curl --user myusername --data-binary '{"jsonrpc": "1.0", "id": "curltest", "method": "getrawaddrman", "params": []}' -H 'content-type: text/plain;' http://127.0.0.1:8332/
```
ACKs for top commit:
willcl-ark:
reACK 352d5eb2a9
amitiuttarwar:
reACK 352d5eb2a9
stratospher:
reACK 352d5eb.
achow101:
ACK 352d5eb2a9
Tree-SHA512: cc462666b5c709617c66b0e3e9a17c4c81e9e295f91bdd9572492d1cb6466fc9b6d48ee805ebe82f9f16010798370effe5c8f4db15065b8c7c0d8637675d615e
Exposing address manager table entries in a hidden RPC allows to introspect
addrman tables in tests and during development.
As response JSON object the following FORMAT1 is choosen:
{
"table": {
"<bucket>/<position>": { "address": "..", "port": .., ... },
"<bucket>/<position>": { "address": "..", "port": .., ... },
"<bucket>/<position>": { "address": "..", "port": .., ... },
...
}
}
An alternative would be FORMAT2
{
"table": {
"bucket": {
"position": { "address": "..", "port": .., ... },
"position": { "address": "..", "port": .., ... },
..
},
"bucket": {
"position": { "address": "..", "port": .., ... },
..
},
}
}
FORMAT1 and FORMAT2 have different encodings for the location of the
address in the address manager. While FORMAT2 might be easier to process
for downstream tools, it also mimics internal addrman mappings, which
might change at some point. Users not interested in the address location
can ignore the location key. They don't have to adapt to a new RPC
response format, when the internal addrman layout changes. Additionally,
FORMAT1 is also slightly easier to to iterate in downstream tools. The
RPC response-building implemenation complexcity is lower with FORMAT1
as we can more easily build a "<bucket>/<position>" key than a multiple
"bucket" objects with multiple "position" objects (FORMAT2).
b3db8c9d5c rpc: bumpfee, improve doc for 'reduce_output' arg (furszy)
Pull request description:
Fixes #28180. Resulted from discussions with S3RK, achow101, and Murch.
The current argument name and description are dangerous as it don't
describe the case where the user selects the recipient output as the
change address. This one could end up been increased by the inputs
minus outputs remainder. Which, when `bumpfee` adds new inputs
to the transaction, leads the process to send more coins to the
recipient. Which is not what the user would expect from a
'reduce_output' param naming.
ACKs for top commit:
S3RK:
ACK b3db8c9d5c
achow101:
ACK b3db8c9d5c
murchandamus:
ACK b3db8c9d5c
Tree-SHA512: 91f607e2f5849041d7c099afdddae11af8bed5b1ac90c9d22921267f272e21b44e107d6968e037f05f958a61fe29e94e5fb44b224fb3606f197f83ec4ba3b1e7
The current argument name and description are dangerous as it don't
describe the case where the user selects the recipient output as the
change address. This one could end up been increased by the inputs
minus outputs remainder. Which, when bumpfee adds new inputs
to the transaction, leads the process to send more coins to the
recipient. Which is not what the user would expect from a
'reduce_output' param naming.
Co-authored-by: Murch <murch@murch.one>
a99e9e655a doc: add release note (ismaelsadeeq)
2b4edf889a test: check `descriptorprocesspsbt` return hex encoded tx (ismaelsadeeq)
c405207a18 rpc: `descriptorprocesspsbt` return hex encoded tx (ismaelsadeeq)
Pull request description:
Coming from [#28414 comment](https://github.com/bitcoin/bitcoin/pull/28414#pullrequestreview-1618684391) Same thing also for `descriptorprocesspsbt`.
Before this PR `descriptorprocesspsbt` returns a boolean `complete` which indicates that the psbt is final, users then have to call `finalizepsbt` to get the hex encoded network transaction.
In this PR if the psbt is complete the return object also has the hex encoded network transaction ready for broadcast with `sendrawtransaction`.
This save users calling `finalizepsbt` with the descriptor, if it is already complete.
ACKs for top commit:
achow101:
ACK a99e9e655a
pinheadmz:
ACK a99e9e655a
ishaanam:
ACK a99e9e655a
Tree-SHA512: c3f1b1391d4df05216c463127cd593f8703840430a99febb54890bc66fadabf9d9530860605f347ec54c1694019173247a0e7a9eb879d3cbb420f9e8d9839b75
f52cb02f70 doc: make it clear that `node` in `addnode` refers to the node's address (brunoerg)
effd1efefb test: `addnode` with an invalid command should throw an error (brunoerg)
56b27b8487 rpc, refactor: clean-up `addnode` (brunoerg)
Pull request description:
This PR:
- Adds test coverage for an invalid `command` in `addnode`.
- Rename `test_getaddednodeinfo` to `test_addnode_getaddednodeinfo` and its log since this function also tests `addnode` and it doesn't worth to split into 2 ones.
- Makes it clear in docs that `node` in `addnode` refers to the node's address. It seemed a little weird for me "The node (see getpeerinfo for nodes)", it could mean a lot of things e.g. the node id.
- Some small improv/clean-up: use `const` where possible, rename some vars, and remove the check for nullance for `command` since it's a non-optional field.
ACKs for top commit:
achow101:
ACK f52cb02f70
jonatack:
ACK f52cb02f70
theStack:
re-ACK f52cb02f70
Tree-SHA512: e4a69e58b784e233463945b4d55a401957f9fe4562c129f59216a44f44fb3221d3449ac578fb35e665ca654c6ade2e741b72c3df78040f7527229c77b6c5b82e
28bac81a34 test: add functional test for getaddrmaninfo (stratospher)
c8eb8dae51 rpc: Introduce getaddrmaninfo for count of addresses stored in new/tried table (stratospher)
Pull request description:
implements https://github.com/bitcoin/bitcoin/issues/26907. split off from #26988 to keep RPC, CLI discussions separate.
This PR introduces a new RPC `getaddrmaninfo`which returns the count of addresses in the new/tried table of a node's addrman broken down by network type. This would be useful for users who want to see the distribution of addresses from different networks across new/tried table in the addrman.
```jsx
$ getaddrmaninfo
Result:
{ (json object) json object with network type as keys
"network" : { (json object) The network (ipv4, ipv6, onion, i2p, cjdns)
"new" : n, (numeric) number of addresses in new table
"tried" : n, (numeric) number of addresses in tried table
"total" : n (numeric) total number of addresses in both new/tried tables from a network
},
...
}
```
### additional context from [original PR](https://github.com/bitcoin/bitcoin/pull/26988)
1. network coverage tests were skipped because there’s a small chance that addresses from different networks could hash to the same bucket and cause count of different network addresses in the tests to fail. see https://github.com/bitcoin/bitcoin/pull/26988#discussion_r1137596851.
2. #26988 uses this RPC in -addrinfo CLI. Slight preference for keeping the RPC hidden since this info will mostly be useful to only super users. see https://github.com/bitcoin/bitcoin/pull/26988#discussion_r1173964808.
ACKs for top commit:
0xB10C:
ACK 28bac81a34
willcl-ark:
reACK 28bac81a34
achow101:
ACK 28bac81a34
brunoerg:
reACK 28bac81a34
theStack:
Code-review ACK 28bac81a34
Tree-SHA512: 346390167e1ebed7ca5c79328ea452633736aff8b7feefea77460e04d4489059334ae78a3f757f32f5fb7827b309d7186bebab3c3760b3dfb016d564a647371a
P2PK scripts are not PKHash destinations, they should have their own
type.
This also results in no longer showing a p2pkh address for p2pk outputs.
However for backwards compatibility, ListCoinst will still do this
conversion.
Make sure that nothing else can change WitnessUnknown's data members by
making them private. Also change the program to use a vector rather than
C-style array.
b3a93b409e test: add functional test for deadlock situation (Martin Zumsande)
3557aa4d0a test: add basic tests for sendmsgtopeer to rpc_net.py (Martin Zumsande)
a9a1d69391 rpc: add test-only sendmsgtopeer rpc (Martin Zumsande)
Pull request description:
This adds a `sendmsgtopeer` rpc (for testing only) that allows a node to send a message (provided in hex) to a peer.
While we would usually use a `p2p` object instead of a node for this in the test framework, that isn't possible in situations where this message needs to trigger an actual interaction of multiple nodes.
Use this rpc to add test coverage for the bug fixed in #27981 (that just got merged):
The test lets two nodes (almost) simultaneously send a single large (4MB) p2p message to each other, which would have caused a deadlock previously (making this test fail), but succeeds now.
As can be seen from the discussion in #27981, it was not easy to reproduce this bug without `sendmsgtopeer`. I would imagine that `sendmsgtopeer` could also be helpful in various other test constellations.
ACKs for top commit:
ajtowns:
ACK b3a93b409e
sipa:
ACK b3a93b409e
achow101:
ACK b3a93b409e
Tree-SHA512: 6e22e72402f3c4dd70cddb9e96ea988444720f7a164031df159fbdd48056c8ac77ac53def045d9208a3ca07437c7c8e34f8b4ebc7066c0a84d81cd53f2f4fa5f
This rpc can be used when we want a node to send a message, but
cannot use a python P2P object, for example for testing of low-level
net transport behavior.
This change makes IsInitialBlockDownload and NotifyHeaderTip functions no
longer tied to individual Chainstate objects. It makes them work with the
ChainstateManager object instead so code is simpler and it is no longer
possible to call them incorrectly with an inactive Chainstate.
This change also makes m_cached_finished_ibd caching easier to reason about,
because now there is only one cached value instead of two (for background and
snapshot chainstates) so the cached IBD state now no longer gets reset when a
snapshot is loaded.
There should be no change in behavior because these functions were always
called on the active ChainState objects.
These changes were discussed previously
https://github.com/bitcoin/bitcoin/pull/27746#discussion_r1246868905 and
https://github.com/bitcoin/bitcoin/pull/27746#discussion_r1237552792 as
possible followups for that PR.
5e3e83b005 RPC/Mining: Document template_request better for getblocktemplate (Luke Dashjr)
de319c6175 RPC/rpcdoccheck: Error if a oneline_description has a quote for a non-string (Luke Dashjr)
7c61e9df90 Bugfix: RPC: Remove quotes from non-string oneline descriptions (Luke Dashjr)
Pull request description:
Various JSON Object parameters had a `oneline_description` with quote characters. Fix those, and extend `rpcdoccheck` to detect them.
Also, slightly improve GBT's oneline description for template_request.
ACKs for top commit:
MarcoFalke:
review ACK 5e3e83b005
Tree-SHA512: 363d1669a661d0acfc19fddb57e777d781c7246f330cf62160e77dde10a6adcb0249db748127067da1afe1b7d17c71cf611d9fdc3664d6bf5b3f30105637769a
91d924ede1 Rename script/standard.{cpp/h} to script/solver.{cpp/h} (Andrew Chow)
bacdb2e208 Clean up script/standard.{h/cpp} includes (Andrew Chow)
f3c9078b4c Clean up things that include script/standard.h (Andrew Chow)
8bbe257bac MOVEONLY: Move datacarrier defaults to policy.h (Andrew Chow)
7a172c76d2 Move CTxDestination to its own file (Andrew Chow)
145f36ec81 Move Taproot{SpendData/Builder} to signingprovider.{h/cpp} (Andrew Chow)
86ea8bed54 Move CScriptID to script.{h/cpp} (Andrew Chow)
b81ebff0d9 Remove ScriptHash from CScriptID constructor (Andrew Chow)
cba69dda3d Move MANDATORY_SCRIPT_VERIFY_FLAGS from script/standard.h to policy/policy.h (Anthony Towns)
Pull request description:
Some future work needs to touch things in script/standard.{h/cpp}, however it is unclear if it is safe to do so as they are included in several different places that could effect standardness and consensus. It contains a mix of policy parameters, consensus parameters, and utilities only used by the wallet. This PR breaks up the various components and renames the files to clearly separate everything.
* `CTxDestination` is moved to a new file `src/addresstype.{cpp/h}`
* `TaprootSpendData` and `TaprootBuilder` (and their utility functions and structs) are moved to `SigningProvider` as these are used only during signing.
* `CScriptID` is moved to `script/script.h` to be next to `CScript`.
* `MANDATORY_SCRIPT_VERIFY_FLAGS` is moved to `interpreter.h`
* The parameters `DEFAULT_ACCEPT_DATACARRIER` and `MAX_OP_RETURN_RELAY` are moved to `policy.h`
* `standard.{cpp/h}` is renamed to `solver.{cpp/h}` since that's all that's left in the file after the above moves
ACKs for top commit:
Sjors:
ACK 91d924ede1
ajtowns:
ACK 91d924ede1
MarcoFalke:
ACK 91d924ede1😇
murchandamus:
ACK 91d924ede1
darosior:
Code review ACK 91d924ede1.
theStack:
Code-review ACK 91d924ede1
Tree-SHA512: d347439890c652081f6a303d99b2bde6c371c96e7f4127c5db469764a17d39981f19884679ba883e28b733fde6142351dd8288c7bc61c379b7eefe7fa7acca1a
fa776e61cd Add importmempool RPC (MarcoFalke)
fa20d734a2 refactor: Add and use kernel::ImportMempoolOptions (MarcoFalke)
fa8866990d doc: Clarify the getmempoolinfo.loaded RPC field documentation (MarcoFalke)
6888886cec Remove Chainstate::LoadMempool (MarcoFalke)
Pull request description:
Currently it is possible to import a mempool by placing it in the datadir and starting the node. However this has many issues:
* Users aren't expected to fiddle with the datadir, possibly corrupting it
* An existing mempool file in the datadir may be overwritten
* The node needs to be restarted
* Importing an untrusted file this way is dangerous, because it can corrupt the mempool
Fix all issues by adding a new RPC.
ACKs for top commit:
ajtowns:
utACK fa776e61cd
achow101:
ACK fa776e61cd
glozow:
reACK fa776e61cd
Tree-SHA512: fcb1a92d6460839283c546c47a2d930c363ac1013c4c50dc5215ddf9fe5e51921d23fe0abfae0a5a7631983cfc7e2fff3788b70f95937d0a989a203be4d67546
