This is based on how much an attacking miner stands to lose in block
rewardy by mining a private chain which double spends a payment.
This is not foolproof, since mining is based on luck, and breaks
down as the attacking miner nears 50% of the network hash rate,
and the estimation is based on a constant block reward.
8fc0cdb wallet2: lower default for subaddress lookahead when restoring with hardware (stoffu)
248310d Move parse_subaddress_lookahead() from simplewallet.cpp to util.cpp (stoffu)
46e90b7 Wallet API: add support for wallet creation from hardware device (stoffu)
8962f00 simplewallet: add optional trusted/untrusted argument to set_daemon (moneromooo-monero)
941a608 util: consider Tor/I2P addresses to be non local (moneromooo-monero)
2b3357e README: mention --untrusted-daemon (moneromooo-monero)
for privacy reasons, so an untrusted node can't easily track
wallets from IP address to IP address, etc. The granularity
is 1024 blocks, which is about a day and a half.
c77d2bfa Add the possibility to export private view key for fast scan. (cslashm)
100b7bc1 Change mutex lock model to avoid dead lock and ensure locks are always released. (cslashm)
641dfc99 Automatic height setup when creating/restoring hw device. (cslashm)
When creating/restoring wallet, if --restore-height option is not used the current estimate
height is used for starting the scan. In other words it is assume we are creating a new account.
If a pre-fork output is spent on both Monero and attack chain,
any post-fork output can be deduced to be a fake output, thereby
decreasing the effective ring size.
The segregate-per-fork-outputs option, on by default, allows
selecting only pre-fork outputs in this case, so that the same
ring can be used when spending it on the other side, which does
not decrease the effective ring size.
This is intended to be SET when intending to spend Monero on the
attack fork, and to be UNSET if not intending to spend Monero
on the attack fork (since it leaks the fact that the output being
spent is pre-fork).
If the user is not certain yet whether they will spend pre-fork
outputs on a key reusing fork, the key-reuse-mitigation2 option
should be SET instead.
If you use this option and intend to spend Monero on both forks,
then spend real Monero first.
This maps key images to rings, so that different forks can reuse
the rings by key image. This avoids revealing the real inputs like
would happen if two forks spent the same outputs with different
rings. This database is meant to be shared with all Monero forks
which don't bother making a new chain, putting users' privacy at
risk in the process. It is placed in a shared data directory by
default ($HOME/.shared-ringdb on UNIX like systems). You may
use --shared-ringdb-dir to override this location, and should
then do so for all Monero forks for them to share the database.
When #3303 was merged, a cyclic dependency chain was generated:
libdevice <- libcncrypto <- libringct <- libdevice
This was because libdevice needs access to a set of basic crypto operations
implemented in libringct such as scalarmultBase(), while libringct also needs
access to abstracted crypto operations implemented in libdevice such as
ecdhEncode(). To untangle this cyclic dependency chain, this patch splits libringct
into libringct_basic and libringct, where the basic crypto ops previously in
libringct are moved into libringct_basic. The cyclic dependency is now resolved
thanks to this separation:
libcncrypto <- libringct_basic <- libdevice <- libcryptonote_basic <- libringct
This eliminates the need for crypto_device.cpp and rctOps_device.cpp.
Also, many abstracted interfaces of hw::device such as encrypt_payment_id() and
get_subaddress_secret_key() were previously implemented in libcryptonote_basic
(cryptonote_format_utils.cpp) and were then called from hw::core::device_default,
which is odd because libdevice is supposed to be independent of libcryptonote_basic.
Therefore, those functions were moved to device_default.cpp.
Previously, a file containing the unencrypted Monero address was
created by default in the wallet's directory. This file might pose
as a privacy risk. The creation of this file is now opt-in and can
be enabled by providing
--create-address-file
- save the new keys file as FOO-watchonly.keys, not FOO.keys-watchonly
- catch any exception (eg, I/O errors) and error out
- print the new keys filename in simplewallet
0e7ad2e2 Wallet API: generalize 'bool testnet' to 'NetworkType nettype' (stoffu)
af773211 Stagenet (stoffu)
cc9a0bee command_line: allow args to depend on more than one args (stoffu)
55f8d917 command_line::get_arg: remove 'required' for dependent args as they're always optional (stoffu)
450306a0 command line: allow has_arg to handle arg_descriptor<bool,false,true> #3318 (stoffu)
9f9e095a Use `genesis_tx` parameter in `generate_genesis_block`. #3261 (Jean Pierre Dudey)
The basic approach it to delegate all sensitive data (master key, secret
ephemeral key, key derivation, ....) and related operations to the device.
As device has low memory, it does not keep itself the values
(except for view/spend keys) but once computed there are encrypted (with AES
are equivalent) and return back to monero-wallet-cli. When they need to be
manipulated by the device, they are decrypted on receive.
Moreover, using the client for storing the value in encrypted form limits
the modification in the client code. Those values are transfered from one
C-structure to another one as previously.
The code modification has been done with the wishes to be open to any
other hardware wallet. To achieve that a C++ class hw::Device has been
introduced. Two initial implementations are provided: the "default", which
remaps all calls to initial Monero code, and the "Ledger", which delegates
all calls to Ledger device.
e4646379 keccak: fix mdlen bounds sanity checking (moneromooo-monero)
2e3e90ac pass large parameters by const ref, not value (moneromooo-monero)
61defd89 blockchain: sanity check number of precomputed hash of hash blocks (moneromooo-monero)
9af6b2d1 ringct: fix infinite loop in unused h2b function (moneromooo-monero)
8cea8d0c simplewallet: double check a new multisig wallet is multisig (moneromooo-monero)
9b98a6ac threadpool: catch exceptions in dtor, to avoid terminate (moneromooo-monero)
24803ed9 blockchain_export: fix buffer overflow in exporter (moneromooo-monero)
f3f7da62 perf_timer: rewrite to make it clear there is no division by zero (moneromooo-monero)
c6ea3df0 performance_tests: remove add_arg call stray extra param (moneromooo-monero)
fa6b4566 fuzz_tests: fix an uninitialized var in setup (moneromooo-monero)
03887f11 keccak: fix sanity check bounds test (moneromooo-monero)
ad11db91 blockchain_db: initialize m_open in base class ctor (moneromooo-monero)
bece67f9 miner: restore std::cout precision after modification (moneromooo-monero)
1aabd14c db_lmdb: check hard fork info drop succeeded (moneromooo-monero)
3160a930 wallet2: remove {set|get}_default_decimal_point and use the same funcs under cryptonote:: instead (stoffu)
7d1088d3 wallet2: make scan_output const and omit keys arg (stoffu)
bc1ee2c2 wallet2: make member functions const when possible (stoffu)
5ae617d5 simplewallet: single out 0 amount destinations as dummy ones (moneromooo-monero)
c1d19f3c wallet2: fix sweep_all sending an atomic unit (moneromooo-monero)
bd5cce07 network_throttle: fix ineffective locking (moneromooo-monero)
e0a61299 network_throttle: remove unused xxx static member (moneromooo-monero)
24f584d9 cryptonote_core: remove unused functions with off by one bugs (moneromooo-monero)
b1634aa3 blockchain: don't leave dangling pointers in this (moneromooo-monero)
8e60b81c cryptonote_core: fix db leak on error (moneromooo-monero)
213e326c abstract_tcp_server2: log init_server errors as fatal (moneromooo-monero)
b51dc566 use const refs in for loops for non tiny types (moneromooo-monero)
f0568ca6 net_parse_helpers: fix regex error checking (moneromooo-monero)
b49ddc76 check accessing an element past the end of a container (moneromooo-monero)
2305bf26 check return value for generate_key_derivation and derive_public_key (moneromooo-monero)
a4240d9f catch const exceptions (moneromooo-monero)
45a1c4c0 add empty container sanity checks when using front() and back() (moneromooo-monero)
56fa6ce1 tests: fix a buffer overread in a unit test (moneromooo-monero)
b4524892 rpc: guard against json parsing a non object (moneromooo-monero)
c2ed8618 easylogging++: avoid buffer underflow (moneromooo-monero)
187a6ab2 epee: trap failure to parse URI from request (moneromooo-monero)
061789b5 checkpoints: trap failure to load JSON checkpoints (moneromooo-monero)
ba2fefb9 checkpoints: pass std::string by const ref, not const value (moneromooo-monero)
38c8f4e0 mlog: terminate a string at last char, just in case (moneromooo-monero)
d753d716 fix a few leaks by throwing objects, not newed pointers to objects (moneromooo-monero)
fe568db8 p2p: use size_t for arbitrary counters instead of uint8_t (moneromooo-monero)
46d6fa35 cryptonote_protocol: sanity check chain hashes from peer (moneromooo-monero)
25584f86 cryptonote_protocol: print peer versions when unexpected (moneromooo-monero)
490a5d41 rpc: do not try to use an invalid txid in relay_tx (moneromooo-monero)
Scheme by luigi1111:
Multisig for RingCT on Monero
2 of 2
User A (coordinator):
Spendkey b,B
Viewkey a,A (shared)
User B:
Spendkey c,C
Viewkey a,A (shared)
Public Address: C+B, A
Both have their own watch only wallet via C+B, a
A will coordinate spending process (though B could easily as well, coordinator is more needed for more participants)
A and B watch for incoming outputs
B creates "half" key images for discovered output D:
I2_D = (Hs(aR)+c) * Hp(D)
B also creates 1.5 random keypairs (one scalar and 2 pubkeys; one on base G and one on base Hp(D)) for each output, storing the scalar(k) (linked to D),
and sending the pubkeys with I2_D.
A also creates "half" key images:
I1_D = (Hs(aR)+b) * Hp(D)
Then I_D = I1_D + I2_D
Having I_D allows A to check spent status of course, but more importantly allows A to actually build a transaction prefix (and thus transaction).
A builds the transaction until most of the way through MLSAG_Gen, adding the 2 pubkeys (per input) provided with I2_D
to his own generated ones where they are needed (secret row L, R).
At this point, A has a mostly completed transaction (but with an invalid/incomplete signature). A sends over the tx and includes r,
which allows B (with the recipient's address) to verify the destination and amount (by reconstructing the stealth address and decoding ecdhInfo).
B then finishes the signature by computing ss[secret_index][0] = ss[secret_index][0] + k - cc[secret_index]*c (secret indices need to be passed as well).
B can then broadcast the tx, or send it back to A for broadcasting. Once B has completed the signing (and verified the tx to be valid), he can add the full I_D
to his cache, allowing him to verify spent status as well.
NOTE:
A and B *must* present key A and B to each other with a valid signature proving they know a and b respectively.
Otherwise, trickery like the following becomes possible:
A creates viewkey a,A, spendkey b,B, and sends a,A,B to B.
B creates a fake key C = zG - B. B sends C back to A.
The combined spendkey C+B then equals zG, allowing B to spend funds at any time!
The signature fixes this, because B does not know a c corresponding to C (and thus can't produce a signature).
2 of 3
User A (coordinator)
Shared viewkey a,A
"spendkey" j,J
User B
"spendkey" k,K
User C
"spendkey" m,M
A collects K and M from B and C
B collects J and M from A and C
C collects J and K from A and B
A computes N = nG, n = Hs(jK)
A computes O = oG, o = Hs(jM)
B anc C compute P = pG, p = Hs(kM) || Hs(mK)
B and C can also compute N and O respectively if they wish to be able to coordinate
Address: N+O+P, A
The rest follows as above. The coordinator possesses 2 of 3 needed keys; he can get the other
needed part of the signature/key images from either of the other two.
Alternatively, if secure communication exists between parties:
A gives j to B
B gives k to C
C gives m to A
Address: J+K+M, A
3 of 3
Identical to 2 of 2, except the coordinator must collect the key images from both of the others.
The transaction must also be passed an additional hop: A -> B -> C (or A -> C -> B), who can then broadcast it
or send it back to A.
N-1 of N
Generally the same as 2 of 3, except participants need to be arranged in a ring to pass their keys around
(using either the secure or insecure method).
For example (ignoring viewkey so letters line up):
[4 of 5]
User: spendkey
A: a
B: b
C: c
D: d
E: e
a -> B, b -> C, c -> D, d -> E, e -> A
Order of signing does not matter, it just must reach n-1 users. A "remaining keys" list must be passed around with
the transaction so the signers know if they should use 1 or both keys.
Collecting key image parts becomes a little messy, but basically every wallet sends over both of their parts with a tag for each.
Thia way the coordinating wallet can keep track of which images have been added and which wallet they come from. Reasoning:
1. The key images must be added only once (coordinator will get key images for key a from both A and B, he must add only one to get the proper key actual key image)
2. The coordinator must keep track of which helper pubkeys came from which wallet (discussed in 2 of 2 section). The coordinator
must choose only one set to use, then include his choice in the "remaining keys" list so the other wallets know which of their keys to use.
You can generalize it further to N-2 of N or even M of N, but I'm not sure there's legitimate demand to justify the complexity. It might
also be straightforward enough to support with minimal changes from N-1 format.
You basically just give each user additional keys for each additional "-1" you desire. N-2 would be 3 keys per user, N-3 4 keys, etc.
The process is somewhat cumbersome:
To create a N/N multisig wallet:
- each participant creates a normal wallet
- each participant runs "prepare_multisig", and sends the resulting string to every other participant
- each participant runs "make_multisig N A B C D...", with N being the threshold and A B C D... being the strings received from other participants (the threshold must currently equal N)
As txes are received, participants' wallets will need to synchronize so that those new outputs may be spent:
- each participant runs "export_multisig FILENAME", and sends the FILENAME file to every other participant
- each participant runs "import_multisig A B C D...", with A B C D... being the filenames received from other participants
Then, a transaction may be initiated:
- one of the participants runs "transfer ADDRESS AMOUNT"
- this partly signed transaction will be written to the "multisig_monero_tx" file
- the initiator sends this file to another participant
- that other participant runs "sign_multisig multisig_monero_tx"
- the resulting transaction is written to the "multisig_monero_tx" file again
- if the threshold was not reached, the file must be sent to another participant, until enough have signed
- the last participant to sign runs "submit_multisig multisig_monero_tx" to relay the transaction to the Monero network
3dffe71b new wipeable_string class to replace std::string passphrases (moneromooo-monero)
7a2a5741 utils: initialize easylogging++ in on_startup (moneromooo-monero)
54950829 use memwipe in a few relevant places (moneromooo-monero)
000666ff add a memwipe function (moneromooo-monero)
- refactoring: proof generation/checking code was moved from simplewallet.cpp to wallet2.cpp
- allow an arbitrary message to be signed together with txid
- introduce two types (outbound & inbound) of tx proofs; with the same syntax, inbound is selected when <address> belongs to this wallet, outbound otherwise. see GitHub thread for more discussion
- wallet RPC: added get_tx_key, check_tx_key, get_tx_proof, check_tx_proof
- wallet API: moved WalletManagerImpl::checkPayment to Wallet::checkTxKey, added Wallet::getTxProof/checkTxProof
- get_tx_key/check_tx_key: handle additional tx keys by concatenating them into a single string
0d9c0db9 Do not build against epee_readline if it was not built (Howard Chu)
178014c9 split off readline code into epee_readline (moneromooo-monero)
a9e14a19 link against readline only for monerod and wallet-wallet-{rpc,cli} (moneromooo-monero)
437421ce wallet: move some scoped_message_writer calls from the libs (moneromooo-monero)
e89994e9 wallet: rejig to avoid prompting in wallet2 (moneromooo-monero)
ec5135e5 move input_line from command_line to simplewallet (moneromooo-monero)
082db75f move cryptonote command line options to cryptonote_core (moneromooo-monero)
