* mempool: remove only valid (Code==0) txs on Update so evil proposers can't drop valid txs in Commit stage. Also remove invalid (Code!=0) txs from the cache so they can be resubmitted. Fixes #3322 @rickyyangz: In the end of commit stage, we will update mempool to remove all the txs in current block. // Update mempool. err = blockExec.mempool.Update( block.Height, block.Txs, TxPreCheck(state), TxPostCheck(state), ) Assum an account has 3 transactions in the mempool, the sequences are 100, 101 and 102 separately, So an evil proposal can only package the 101 and 102 transactions into its proposal block, and leave 100 still in mempool, then the two txs will be removed from all validators' mempool when commit. So the account lost the two valid txs. @ebuchman: In the longer term we may want to do something like #2639 so we can validate txs before we commit the block. But even in this case we'd only want to run the equivalent of CheckTx, which means the DeliverTx could still fail even if the CheckTx passes depending on how the app handles the ABCI Code semantics. So more work will be required around the ABCI code. See also #2185 * add changelog entry and tests * improve changelog message * reformat code
Tendermint
Byzantine-Fault Tolerant State Machines. Or Blockchain, for short.
Branch | Tests | Coverage |
---|---|---|
master | ||
develop |
Tendermint Core is Byzantine Fault Tolerant (BFT) middleware that takes a state transition machine - written in any programming language - and securely replicates it on many machines.
For protocol details, see the specification.
For detailed analysis of the consensus protocol, including safety and liveness proofs, see our recent paper, "The latest gossip on BFT consensus".
A Note on Production Readiness
While Tendermint is being used in production in private, permissioned environments, we are still working actively to harden and audit it in preparation for use in public blockchains, such as the Cosmos Network. We are also still making breaking changes to the protocol and the APIs. Thus, we tag the releases as alpha software.
In any case, if you intend to run Tendermint in production, please contact us and join the chat.
Security
To report a security vulnerability, see our bug bounty program
For examples of the kinds of bugs we're looking for, see SECURITY.md
Minimum requirements
Requirement | Notes |
---|---|
Go version | Go1.11.4 or higher |
Documentation
Complete documentation can be found on the website.
Install
See the install instructions
Quick Start
- Single node
- Local cluster using docker-compose
- Remote cluster using terraform and ansible
- Join the Cosmos testnet
Contributing
Please abide by the Code of Conduct in all interactions, and the contributing guidelines when submitting code.
Join the larger community on the forum and the chat.
To learn more about the structure of the software, watch the Developer Sessions and read some Architectural Decision Records.
Learn more by reading the code and comparing it to the specification.
Versioning
Semantic Versioning
Tendermint uses Semantic Versioning to determine when and how the version changes. According to SemVer, anything in the public API can change at any time before version 1.0.0
To provide some stability to Tendermint users in these 0.X.X days, the MINOR version is used to signal breaking changes across a subset of the total public API. This subset includes all interfaces exposed to other processes (cli, rpc, p2p, etc.), but does not include the in-process Go APIs.
That said, breaking changes in the following packages will be documented in the CHANGELOG even if they don't lead to MINOR version bumps:
- crypto
- types
- rpc/client
- config
- node
- libs
- bech32
- common
- db
- errors
- log
Exported objects in these packages that are not covered by the versioning scheme
are explicitly marked by // UNSTABLE
in their go doc comment and may change at any
time without notice. Functions, types, and values in any other package may also change at any time.
Upgrades
In an effort to avoid accumulating technical debt prior to 1.0.0, we do not guarantee that breaking changes (ie. bumps in the MINOR version) will work with existing tendermint blockchains. In these cases you will have to start a new blockchain, or write something custom to get the old data into the new chain.
However, any bump in the PATCH version should be compatible with existing histories (if not please open an issue).
For more information on upgrading, see UPGRADING.md
Resources
Tendermint Core
For details about the blockchain data structures and the p2p protocols, see the Tendermint specification.
For details on using the software, see the documentation which is also hosted at: https://tendermint.com/docs/
Tools
Benchmarking and monitoring is provided by tm-bench
and tm-monitor
, respectively.
Their code is found here and these binaries need to be built seperately.
Additional documentation is found here.
Sub-projects
Applications
- Cosmos SDK; a cryptocurrency application framework
- Ethermint; Ethereum on Tendermint
- Many more