* fix ns delete owner count
* add a new success code and refactor success checks, limit ns delete operations to 256 entries per txn
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Co-authored-by: Richard Holland <richard.holland@starstone.co.nz>
Add the ability to mark amendments as obsolete. There are some known
amendments that should not be voted for because they are broken (or
similar reasons).
This commit marks four amendments as obsolete:
1. `CryptoConditionsSuite`
2. `NonFungibleTokensV1`
3. `fixNFTokenDirV1`
4. `fixNFTokenNegOffer`
When an amendment is `Obsolete`, voting for the amendment is prevented.
A determined operator can still vote for the amendment by changing the
source, and doing so does not break any protocol rules.
The "feature" command now does not modify the vote for obsolete
amendments.
Before this change, there were two options for an amendment's
`DefaultVote` behavior: yes and no.
After this change, there are three options for an amendment's
`VoteBehavior`: DefaultYes, DefaultNo, and Obsolete.
To be clear, if an obsolete amendment were to (somehow) be activated by
consensus, the server still has the code to process transactions
according to that amendment, and would not be amendment blocked. It
would function the same as if it had been voting "no" on the amendment.
Resolves#4014.
Incorporates review feedback from @scottschurr.
Without the protocol amendment introduced by this commit, an NFT ID can
be reminted in this manner:
1. Alice creates an account and mints an NFT.
2. Alice burns the NFT with an `NFTokenBurn` transaction.
3. Alice deletes her account with an `AccountDelete` transaction.
4. Alice re-creates her account.
5. Alice mints an NFT with an `NFTokenMint` transaction with params:
`NFTokenTaxon` = 0, `Flags` = 9).
This will mint a NFT with the same `NFTokenID` as the one minted in step
1. The params that construct the NFT ID will cause a collision in
`NFTokenID` if their values are equal before and after the remint.
With the `fixNFTokenRemint` amendment, there is a new sequence number
construct which avoids this scenario:
- A new `AccountRoot` field, `FirstNFTSequence`, stays constant over
time.
- This field is set to the current account sequence when the account
issues their first NFT.
- Otherwise, it is not set.
- The sequence of a newly-minted NFT is computed by: `FirstNFTSequence +
MintedNFTokens`.
- `MintedNFTokens` is then incremented by 1 for each mint.
Furthermore, there is a new account deletion restriction:
- An account can only be deleted if `FirstNFTSequence + MintedNFTokens +
256` is less than the current ledger sequence.
- 256 was chosen because it already exists in the current account
deletion constraint.
Without this restriction, an NFT may still be remintable. Example
scenario:
1. Alice's account sequence is at 1.
2. Bob is Alice's authorized minter.
3. Bob mints 500 NFTs for Alice. The NFTs will have sequences 1-501, as
NFT sequence is computed by `FirstNFTokenSequence + MintedNFTokens`).
4. Alice deletes her account at ledger 257 (as required by the existing
`AccountDelete` amendment).
5. Alice re-creates her account at ledger 258.
6. Alice mints an NFT. `FirstNFTokenSequence` initializes to her account
sequence (258), and `MintedNFTokens` initializes as 0. This
newly-minted NFT would have a sequence number of 258, which is a
duplicate of what she issued through authorized minting before she
deleted her account.
---------
Signed-off-by: Shawn Xie <shawnxie920@gmail.com>
* Introduces amendment `XRPFees`
* Convert fee voting and protocol messages to use XRPAmounts
* Includes Validations, Change transactions, the "Fees" ledger object,
and subscription messages
* Improve handling of 0 drop reference fee with TxQ. For use with networks that do not want to require fees
* Note that fee escalation logic is still in place, which may cause the
open ledger fee to rise if the network is busy. 0 drop transactions
will still queue, and fee escalation can be effectively disabled by
modifying the configuration on all nodes
* Change default network reserves to match Mainnet
* Name the new SFields *Drops (not *XRP)
* Reserve SField IDs for Hooks
* Clarify comments explaining the ttFEE transaction field validation
