github.com/vipernet-xyz/tm@v0.34.24/spec/core/data_structures.md (about) 1 # Data Structures 2 3 Here we describe the data structures in the Tendermint blockchain and the rules for validating them. 4 5 The Tendermint blockchains consists of a short list of data types: 6 7 - [Data Structures](#data-structures) 8 - [Block](#block) 9 - [Execution](#execution) 10 - [Header](#header) 11 - [Version](#version) 12 - [BlockID](#blockid) 13 - [PartSetHeader](#partsetheader) 14 - [Part](#part) 15 - [Time](#time) 16 - [Data](#data) 17 - [Commit](#commit) 18 - [CommitSig](#commitsig) 19 - [BlockIDFlag](#blockidflag) 20 - [Vote](#vote) 21 - [CanonicalVote](#canonicalvote) 22 - [Proposal](#proposal) 23 - [SignedMsgType](#signedmsgtype) 24 - [Signature](#signature) 25 - [EvidenceList](#evidencelist) 26 - [Evidence](#evidence) 27 - [DuplicateVoteEvidence](#duplicatevoteevidence) 28 - [LightClientAttackEvidence](#lightclientattackevidence) 29 - [LightBlock](#lightblock) 30 - [SignedHeader](#signedheader) 31 - [ValidatorSet](#validatorset) 32 - [Validator](#validator) 33 - [Address](#address) 34 - [ConsensusParams](#consensusparams) 35 - [BlockParams](#blockparams) 36 - [EvidenceParams](#evidenceparams) 37 - [ValidatorParams](#validatorparams) 38 - [VersionParams](#versionparams) 39 - [Proof](#proof) 40 41 42 ## Block 43 44 A block consists of a header, transactions, votes (the commit), 45 and a list of evidence of malfeasance (ie. signing conflicting votes). 46 47 | Name | Type | Description | Validation | 48 |--------|-------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------| 49 | Header | [Header](#header) | Header corresponding to the block. This field contains information used throughout consensus and other areas of the protocol. To find out what it contains, visit [header](#header) | Must adhere to the validation rules of [header](#header) | 50 | Data | [Data](#data) | Data contains a list of transactions. The contents of the transaction is unknown to Tendermint. | This field can be empty or populated, but no validation is performed. Applications can perform validation on individual transactions prior to block creation using [checkTx](../abci/abci.md#checktx). 51 | Evidence | [EvidenceList](#evidence_list) | Evidence contains a list of infractions committed by validators. | Can be empty, but when populated the validations rules from [evidenceList](#evidence_list) apply | 52 | LastCommit | [Commit](#commit) | `LastCommit` includes one vote for every validator. All votes must either be for the previous block, nil or absent. If a vote is for the previous block it must have a valid signature from the corresponding validator. The sum of the voting power of the validators that voted must be greater than 2/3 of the total voting power of the complete validator set. The number of votes in a commit is limited to 10000 (see `types.MaxVotesCount`). | Must be empty for the initial height and must adhere to the validation rules of [commit](#commit). | 53 54 ## Execution 55 56 Once a block is validated, it can be executed against the state. 57 58 The state follows this recursive equation: 59 60 ```go 61 state(initialHeight) = InitialState 62 state(h+1) <- Execute(state(h), ABCIApp, block(h)) 63 ``` 64 65 where `InitialState` includes the initial consensus parameters and validator set, 66 and `ABCIApp` is an ABCI application that can return results and changes to the validator 67 set (TODO). Execute is defined as: 68 69 ```go 70 func Execute(s State, app ABCIApp, block Block) State { 71 // Fuction ApplyBlock executes block of transactions against the app and returns the new root hash of the app state, 72 // modifications to the validator set and the changes of the consensus parameters. 73 AppHash, ValidatorChanges, ConsensusParamChanges := app.ApplyBlock(block) 74 75 nextConsensusParams := UpdateConsensusParams(state.ConsensusParams, ConsensusParamChanges) 76 return State{ 77 ChainID: state.ChainID, 78 InitialHeight: state.InitialHeight, 79 LastResults: abciResponses.DeliverTxResults, 80 AppHash: AppHash, 81 InitialHeight: state.InitialHeight, 82 LastValidators: state.Validators, 83 Validators: state.NextValidators, 84 NextValidators: UpdateValidators(state.NextValidators, ValidatorChanges), 85 ConsensusParams: nextConsensusParams, 86 Version: { 87 Consensus: { 88 AppVersion: nextConsensusParams.Version.AppVersion, 89 }, 90 }, 91 } 92 } 93 ``` 94 95 Validating a new block is first done prior to the `prevote`, `precommit` & `finalizeCommit` stages. 96 97 The steps to validate a new block are: 98 99 - Check the validity rules of the block and its fields. 100 - Check the versions (Block & App) are the same as in local state. 101 - Check the chainID's match. 102 - Check the height is correct. 103 - Check the `LastBlockID` corresponds to BlockID currently in state. 104 - Check the hashes in the header match those in state. 105 - Verify the LastCommit against state, this step is skipped for the initial height. 106 - This is where checking the signatures correspond to the correct block will be made. 107 - Make sure the proposer is part of the validator set. 108 - Validate bock time. 109 - Make sure the new blocks time is after the previous blocks time. 110 - Calculate the medianTime and check it against the blocks time. 111 - If the blocks height is the initial height then check if it matches the genesis time. 112 - Validate the evidence in the block. Note: Evidence can be empty 113 114 ## Header 115 116 A block header contains metadata about the block and about the consensus, as well as commitments to 117 the data in the current block, the previous block, and the results returned by the application: 118 119 | Name | Type | Description | Validation | 120 |-------------------|---------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| 121 | Version | [Version](#version) | Version defines the application and protocol version being used. | Must adhere to the validation rules of [Version](#version) | 122 | ChainID | String | ChainID is the ID of the chain. This must be unique to your chain. | ChainID must be less than 50 bytes. | 123 | Height | uint64 | Height is the height for this header. | Must be > 0, >= initialHeight, and == previous Height+1 | 124 | Time | [Time](#time) | The timestamp is equal to the weighted median of validators present in the last commit. Read more on time in the [BFT-time section](../consensus/bft-time.md). Note: the timestamp of a vote must be greater by at least one millisecond than that of the block being voted on. | Time must be >= previous header timestamp + consensus parameters TimeIotaMs. The timestamp of the first block must be equal to the genesis time (since there's no votes to compute the median). | 125 | LastBlockID | [BlockID](#blockid) | BlockID of the previous block. | Must adhere to the validation rules of [blockID](#blockid). The first block has `block.Header.LastBlockID == BlockID{}`. | 126 | LastCommitHash | slice of bytes (`[]byte`) | MerkleRoot of the lastCommit's signatures. The signatures represent the validators that committed to the last block. The first block has an empty slices of bytes for the hash. | Must be of length 32 | 127 | DataHash | slice of bytes (`[]byte`) | MerkleRoot of the hash of transactions. **Note**: The transactions are hashed before being included in the merkle tree, the leaves of the Merkle tree are the hashes, not the transactions themselves. | Must be of length 32 | 128 | ValidatorHash | slice of bytes (`[]byte`) | MerkleRoot of the current validator set. The validators are first sorted by voting power (descending), then by address (ascending) prior to computing the MerkleRoot. | Must be of length 32 | 129 | NextValidatorHash | slice of bytes (`[]byte`) | MerkleRoot of the next validator set. The validators are first sorted by voting power (descending), then by address (ascending) prior to computing the MerkleRoot. | Must be of length 32 | 130 | ConsensusHash | slice of bytes (`[]byte`) | Hash of the protobuf encoded consensus parameters. | Must be of length 32 | 131 | AppHash | slice of bytes (`[]byte`) | Arbitrary byte array returned by the application after executing and commiting the previous block. It serves as the basis for validating any merkle proofs that comes from the ABCI application and represents the state of the actual application rather than the state of the blockchain itself. The first block's `block.Header.AppHash` is given by `ResponseInitChain.app_hash`. | This hash is determined by the application, Tendermint can not perform validation on it. | 132 | LastResultHash | slice of bytes (`[]byte`) | `LastResultsHash` is the root hash of a Merkle tree built from `ResponseDeliverTx` responses (`Log`,`Info`, `Codespace` and `Events` fields are ignored). | Must be of length 32. The first block has `block.Header.ResultsHash == MerkleRoot(nil)`, i.e. the hash of an empty input, for RFC-6962 conformance. | 133 | EvidenceHash | slice of bytes (`[]byte`) | MerkleRoot of the evidence of Byzantine behaviour included in this block. | Must be of length 32 | 134 | ProposerAddress | slice of bytes (`[]byte`) | Address of the original proposer of the block. Validator must be in the current validatorSet. | Must be of length 20 | 135 136 ## Version 137 138 NOTE: that this is more specifically the consensus version and doesn't include information like the 139 P2P Version. (TODO: we should write a comprehensive document about 140 versioning that this can refer to) 141 142 | Name | type | Description | Validation | 143 |-------|--------|-----------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------| 144 | Block | uint64 | This number represents the version of the block protocol and must be the same throughout an operational network | Must be equal to protocol version being used in a network (`block.Version.Block == state.Version.Consensus.Block`) | 145 | App | uint64 | App version is decided on by the application. Read [here](../abci/abci.md#info) | `block.Version.App == state.Version.Consensus.App` | 146 147 ## BlockID 148 149 The `BlockID` contains two distinct Merkle roots of the block. The `BlockID` includes these two hashes, as well as the number of parts (ie. `len(MakeParts(block))`) 150 151 | Name | Type | Description | Validation | 152 |---------------|---------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------| 153 | Hash | slice of bytes (`[]byte`) | MerkleRoot of all the fields in the header (ie. `MerkleRoot(header)`. | hash must be of length 32 | 154 | PartSetHeader | [PartSetHeader](#PartSetHeader) | Used for secure gossiping of the block during consensus, is the MerkleRoot of the complete serialized block cut into parts (ie. `MerkleRoot(MakeParts(block))`). | Must adhere to the validation rules of [PartSetHeader](#PartSetHeader) | 155 156 See [MerkleRoot](./encoding.md#MerkleRoot) for details. 157 158 ## PartSetHeader 159 160 | Name | Type | Description | Validation | 161 |-------|---------------------------|-----------------------------------|----------------------| 162 | Total | int32 | Total amount of parts for a block | Must be > 0 | 163 | Hash | slice of bytes (`[]byte`) | MerkleRoot of a serialized block | Must be of length 32 | 164 165 ## Part 166 167 Part defines a part of a block. In Tendermint blocks are broken into `parts` for gossip. 168 169 | Name | Type | Description | Validation | 170 |-------|-----------------|-----------------------------------|----------------------| 171 | index | int32 | Total amount of parts for a block | Must be > 0 | 172 | bytes | bytes | MerkleRoot of a serialized block | Must be of length 32 | 173 | proof | [Proof](#proof) | MerkleRoot of a serialized block | Must be of length 32 | 174 175 ## Time 176 177 Tendermint uses the [Google.Protobuf.Timestamp](https://developers.google.com/protocol-buffers/docs/reference/google.protobuf#google.protobuf.Timestamp) 178 format, which uses two integers, one 64 bit integer for Seconds and a 32 bit integer for Nanoseconds. 179 180 ## Data 181 182 Data is just a wrapper for a list of transactions, where transactions are arbitrary byte arrays: 183 184 | Name | Type | Description | Validation | 185 |------|----------------------------|------------------------|-----------------------------------------------------------------------------| 186 | Txs | Matrix of bytes ([][]byte) | Slice of transactions. | Validation does not occur on this field, this data is unknown to Tendermint | 187 188 ## Commit 189 190 Commit is a simple wrapper for a list of signatures, with one for each validator. It also contains the relevant BlockID, height and round: 191 192 | Name | Type | Description | Validation | 193 |------------|----------------------------------|----------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------| 194 | Height | uint64 | Height at which this commit was created. | Must be > 0 | 195 | Round | int32 | Round that the commit corresponds to. | Must be > 0 | 196 | BlockID | [BlockID](#blockid) | The blockID of the corresponding block. | Must adhere to the validation rules of [BlockID](#blockid). | 197 | Signatures | Array of [CommitSig](#commitsig) | Array of commit signatures that correspond to current validator set. | Length of signatures must be > 0 and adhere to the validation of each individual [Commitsig](#commitsig) | 198 199 ## CommitSig 200 201 `CommitSig` represents a signature of a validator, who has voted either for nil, 202 a particular `BlockID` or was absent. It's a part of the `Commit` and can be used 203 to reconstruct the vote set given the validator set. 204 205 | Name | Type | Description | Validation | 206 |------------------|-----------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------| 207 | BlockIDFlag | [BlockIDFlag](#blockidflag) | Represents the validators participation in consensus: Either voted for the block that received the majority, voted for another block, voted nil or did not vote | Must be one of the fields in the [BlockIDFlag](#blockidflag) enum | 208 | ValidatorAddress | [Address](#address) | Address of the validator | Must be of length 20 | 209 | Timestamp | [Time](#time) | This field will vary from `CommitSig` to `CommitSig`. It represents the timestamp of the validator. | [Time](#time) | 210 | Signature | [Signature](#signature) | Signature corresponding to the validators participation in consensus. | The length of the signature must be > 0 and < than 64 | 211 212 NOTE: `ValidatorAddress` and `Timestamp` fields may be removed in the future 213 (see [ADR-25](https://github.com/vipernet-xyz/tm/blob/main/docs/architecture/adr-025-commit.md)). 214 215 ## BlockIDFlag 216 217 BlockIDFlag represents which BlockID the [signature](#commitsig) is for. 218 219 ```go 220 enum BlockIDFlag { 221 BLOCK_ID_FLAG_UNKNOWN = 0; 222 BLOCK_ID_FLAG_ABSENT = 1; // signatures for other blocks are also considered absent 223 BLOCK_ID_FLAG_COMMIT = 2; 224 BLOCK_ID_FLAG_NIL = 3; 225 } 226 ``` 227 228 ## Vote 229 230 A vote is a signed message from a validator for a particular block. 231 The vote includes information about the validator signing it. When stored in the blockchain or propagated over the network, votes are encoded in Protobuf. 232 233 | Name | Type | Description | Validation | 234 |------------------|---------------------------------|---------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------| 235 | Type | [SignedMsgType](#signedmsgtype) | Either prevote or precommit. [SignedMsgType](#signedmsgtype) | A Vote is valid if its corresponding fields are included in the enum [signedMsgType](#signedmsgtype) | 236 | Height | uint64 | Height for which this vote was created for | Must be > 0 | 237 | Round | int32 | Round that the commit corresponds to. | Must be > 0 | 238 | BlockID | [BlockID](#blockid) | The blockID of the corresponding block. | [BlockID](#blockid) | 239 | Timestamp | [Time](#Time) | Timestamp represents the time at which a validator signed. | [Time](#time) | 240 | ValidatorAddress | slice of bytes (`[]byte`) | Address of the validator | Length must be equal to 20 | 241 | ValidatorIndex | int32 | Index at a specific block height that corresponds to the Index of the validator in the set. | must be > 0 | 242 | Signature | slice of bytes (`[]byte`) | Signature by the validator if they participated in consensus for the associated bock. | Length of signature must be > 0 and < 64 | 243 244 ## CanonicalVote 245 246 CanonicalVote is for validator signing. This type will not be present in a block. Votes are represented via `CanonicalVote` and also encoded using protobuf via `type.SignBytes` which includes the `ChainID`, and uses a different ordering of 247 the fields. 248 249 ```proto 250 message CanonicalVote { 251 SignedMsgType type = 1; 252 fixed64 height = 2; 253 sfixed64 round = 3; 254 CanonicalBlockID block_id = 4; 255 google.protobuf.Timestamp timestamp = 5; 256 string chain_id = 6; 257 } 258 ``` 259 260 For signing, votes are represented via [`CanonicalVote`](#canonicalvote) and also encoded using protobuf via 261 `type.SignBytes` which includes the `ChainID`, and uses a different ordering of 262 the fields. 263 264 We define a method `Verify` that returns `true` if the signature verifies against the pubkey for the `SignBytes` 265 using the given ChainID: 266 267 ```go 268 func (vote *Vote) Verify(chainID string, pubKey crypto.PubKey) error { 269 if !bytes.Equal(pubKey.Address(), vote.ValidatorAddress) { 270 return ErrVoteInvalidValidatorAddress 271 } 272 v := vote.ToProto() 273 if !pubKey.VerifyBytes(types.VoteSignBytes(chainID, v), vote.Signature) { 274 return ErrVoteInvalidSignature 275 } 276 return nil 277 } 278 ``` 279 280 ## Proposal 281 282 Proposal contains height and round for which this proposal is made, BlockID as a unique identifier 283 of proposed block, timestamp, and POLRound (a so-called Proof-of-Lock (POL) round) that is needed for 284 termination of the consensus. If POLRound >= 0, then BlockID corresponds to the block that 285 is locked in POLRound. The message is signed by the validator private key. 286 287 | Name | Type | Description | Validation | 288 |-----------|---------------------------------|---------------------------------------------------------------------------------------|---------------------------------------------------------| 289 | Type | [SignedMsgType](#signedmsgtype) | Represents a Proposal [SignedMsgType](#signedmsgtype) | Must be `ProposalType` [signedMsgType](#signedmsgtype) | 290 | Height | uint64 | Height for which this vote was created for | Must be > 0 | 291 | Round | int32 | Round that the commit corresponds to. | Must be > 0 | 292 | POLRound | int64 | Proof of lock | Must be > 0 | 293 | BlockID | [BlockID](#blockid) | The blockID of the corresponding block. | [BlockID](#blockid) | 294 | Timestamp | [Time](#Time) | Timestamp represents the time at which a validator signed. | [Time](#time) | 295 | Signature | slice of bytes (`[]byte`) | Signature by the validator if they participated in consensus for the associated bock. | Length of signature must be > 0 and < 64 | 296 297 ## SignedMsgType 298 299 Signed message type represents a signed messages in consensus. 300 301 ```proto 302 enum SignedMsgType { 303 304 SIGNED_MSG_TYPE_UNKNOWN = 0; 305 // Votes 306 SIGNED_MSG_TYPE_PREVOTE = 1; 307 SIGNED_MSG_TYPE_PRECOMMIT = 2; 308 309 // Proposal 310 SIGNED_MSG_TYPE_PROPOSAL = 32; 311 } 312 ``` 313 314 ## Signature 315 316 Signatures in Tendermint are raw bytes representing the underlying signature. 317 318 See the [signature spec](./encoding.md#key-types) for more. 319 320 ## EvidenceList 321 322 EvidenceList is a simple wrapper for a list of evidence: 323 324 | Name | Type | Description | Validation | 325 |----------|--------------------------------|----------------------------------------|-----------------------------------------------------------------| 326 | Evidence | Array of [Evidence](#evidence) | List of verified [evidence](#evidence) | Validation adheres to individual types of [Evidence](#evidence) | 327 328 ## Evidence 329 330 Evidence in Tendermint is used to indicate breaches in the consensus by a validator. 331 332 More information on how evidence works in Tendermint can be found [here](../consensus/evidence.md) 333 334 ### DuplicateVoteEvidence 335 336 `DuplicateVoteEvidence` represents a validator that has voted for two different blocks 337 in the same round of the same height. Votes are lexicographically sorted on `BlockID`. 338 339 | Name | Type | Description | Validation | 340 |------------------|---------------|--------------------------------------------------------------------|-----------------------------------------------------| 341 | VoteA | [Vote](#vote) | One of the votes submitted by a validator when they equivocated | VoteA must adhere to [Vote](#vote) validation rules | 342 | VoteB | [Vote](#vote) | The second vote submitted by a validator when they equivocated | VoteB must adhere to [Vote](#vote) validation rules | 343 | TotalVotingPower | int64 | The total power of the validator set at the height of equivocation | Must be equal to nodes own copy of the data | 344 | ValidatorPower | int64 | Power of the equivocating validator at the height | Must be equal to the nodes own copy of the data | 345 | Timestamp | [Time](#Time) | Time of the block where the equivocation occurred | Must be equal to the nodes own copy of the data | 346 347 ### LightClientAttackEvidence 348 349 `LightClientAttackEvidence` is a generalized evidence that captures all forms of known attacks on 350 a light client such that a full node can verify, propose and commit the evidence on-chain for 351 punishment of the malicious validators. There are three forms of attacks: Lunatic, Equivocation 352 and Amnesia. These attacks are exhaustive. You can find a more detailed overview of this [here](../light-client/accountability#the_misbehavior_of_faulty_validators) 353 354 | Name | Type | Description | Validation | 355 |----------------------|------------------------------------|----------------------------------------------------------------------|------------------------------------------------------------------| 356 | ConflictingBlock | [LightBlock](#LightBlock) | Read Below | Must adhere to the validation rules of [lightBlock](#lightblock) | 357 | CommonHeight | int64 | Read Below | must be > 0 | 358 | Byzantine Validators | Array of [Validators](#Validators) | validators that acted maliciously | Read Below | 359 | TotalVotingPower | int64 | The total power of the validator set at the height of the infraction | Must be equal to the nodes own copy of the data | 360 | Timestamp | [Time](#Time) | Time of the block where the infraction occurred | Must be equal to the nodes own copy of the data | 361 362 ## LightBlock 363 364 LightBlock is the core data structure of the [light client](../light-client/README.md). It combines two data structures needed for verification ([signedHeader](#signedheader) & [validatorSet](#validatorset)). 365 366 | Name | Type | Description | Validation | 367 |--------------|-------------------------------|----------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------| 368 | SignedHeader | [SignedHeader](#signedheader) | The header and commit, these are used for verification purposes. To find out more visit [light client docs](../light-client/README.md) | Must not be nil and adhere to the validation rules of [signedHeader](#signedheader) | 369 | ValidatorSet | [ValidatorSet](#validatorset) | The validatorSet is used to help with verify that the validators in that committed the infraction were truly in the validator set. | Must not be nil and adhere to the validation rules of [validatorSet](#validatorset) | 370 371 The `SignedHeader` and `ValidatorSet` are linked by the hash of the validator set(`SignedHeader.ValidatorsHash == ValidatorSet.Hash()`. 372 373 ## SignedHeader 374 375 The SignedhHeader is the [header](#header) accompanied by the commit to prove it. 376 377 | Name | Type | Description | Validation | 378 |--------|-------------------|-------------------|-----------------------------------------------------------------------------------| 379 | Header | [Header](#Header) | [Header](#header) | Header cannot be nil and must adhere to the [Header](#Header) validation criteria | 380 | Commit | [Commit](#commit) | [Commit](#commit) | Commit cannot be nil and must adhere to the [Commit](#commit) criteria | 381 382 ## ValidatorSet 383 384 | Name | Type | Description | Validation | 385 |------------|----------------------------------|----------------------------------------------------|-------------------------------------------------------------------------------------------------------------------| 386 | Validators | Array of [validator](#validator) | List of the active validators at a specific height | The list of validators can not be empty or nil and must adhere to the validation rules of [validator](#validator) | 387 | Proposer | [validator](#validator) | The block proposer for the corresponding block | The proposer cannot be nil and must adhere to the validation rules of [validator](#validator) | 388 389 ## Validator 390 391 | Name | Type | Description | Validation | 392 |------------------|---------------------------|---------------------------------------------------------------------------------------------------|---------------------------------------------------| 393 | Address | [Address](#address) | Validators Address | Length must be of size 20 | 394 | Pubkey | slice of bytes (`[]byte`) | Validators Public Key | must be a length greater than 0 | 395 | VotingPower | int64 | Validators voting power | cannot be < 0 | 396 | ProposerPriority | int64 | Validators proposer priority. This is used to gauge when a validator is up next to propose blocks | No validation, value can be negative and positive | 397 398 ## Address 399 400 Address is a type alias of a slice of bytes. The address is calculated by hashing the public key using sha256 and truncating it to only use the first 20 bytes of the slice. 401 402 ```go 403 const ( 404 TruncatedSize = 20 405 ) 406 407 func SumTruncated(bz []byte) []byte { 408 hash := sha256.Sum256(bz) 409 return hash[:TruncatedSize] 410 } 411 ``` 412 413 ## ConsensusParams 414 415 | Name | Type | Description | Field Number | 416 |-----------|-------------------------------------|------------------------------------------------------------------------------|--------------| 417 | block | [BlockParams](#blockparams) | Parameters limiting the size of a block and time between consecutive blocks. | 1 | 418 | evidence | [EvidenceParams](#evidenceparams) | Parameters limiting the validity of evidence of byzantine behaviour. | 2 | 419 | validator | [ValidatorParams](#validatorparams) | Parameters limiting the types of public keys validators can use. | 3 | 420 | version | [BlockParams](#blockparams) | The ABCI application version. | 4 | 421 422 ### BlockParams 423 424 | Name | Type | Description | Field Number | 425 |--------------|-------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------| 426 | max_bytes | int64 | Max size of a block, in bytes. | 1 | 427 | max_gas | int64 | Max sum of `GasWanted` in a proposed block. NOTE: blocks that violate this may be committed if there are Byzantine proposers. It's the application's responsibility to handle this when processing a block! | 2 | 428 429 ### EvidenceParams 430 431 | Name | Type | Description | Field Number | 432 |--------------------|------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------| 433 | max_age_num_blocks | int64 | Max age of evidence, in blocks. | 1 | 434 | max_age_duration | [google.protobuf.Duration](https://developers.google.com/protocol-buffers/docs/reference/google.protobuf#google.protobuf.Duration) | Max age of evidence, in time. It should correspond with an app's "unbonding period" or other similar mechanism for handling [Nothing-At-Stake attacks](https://github.com/ethereum/wiki/wiki/Proof-of-Stake-FAQ#what-is-the-nothing-at-stake-problem-and-how-can-it-be-fixed). | 2 | 435 | max_bytes | int64 | maximum size in bytes of total evidence allowed to be entered into a block | 3 | 436 437 ### ValidatorParams 438 439 | Name | Type | Description | Field Number | 440 |---------------|-----------------|-----------------------------------------------------------------------|--------------| 441 | pub_key_types | repeated string | List of accepted public key types. Uses same naming as `PubKey.Type`. | 1 | 442 443 ### VersionParams 444 445 | Name | Type | Description | Field Number | 446 |-------------|--------|-------------------------------|--------------| 447 | app_version | uint64 | The ABCI application version. | 1 | 448 449 ## Proof 450 451 | Name | Type | Description | Field Number | 452 |-----------|----------------|-----------------------------------------------|--------------| 453 | total | int64 | Total number of items. | 1 | 454 | index | int64 | Index item to prove. | 2 | 455 | leaf_hash | bytes | Hash of item value. | 3 | 456 | aunts | repeated bytes | Hashes from leaf's sibling to a root's child. | 4 |