# DCRM SDK ## **DCRM SDK BETA** Note : dcrm-sdk is considered beta software. We make no warranties or guarantees of its security or stability.\* Github repo: ## Introduction DCRM SDK is a distributed key generation and distributed signature module that forms the cornerstone of decentralized value exchange. This technology was developed for over a year, with the feedback of 4 leading cryptographers: Rosario Gennaro, Steven Goldfeder, Pascal Paillier, Louis Goubin. When used in context of blockchain, this module can serve as a non-custodial solution, a keyless wallet, a component to an interoperable solution, and more. Please read the [Wiki](https://github.com/fsn-dev/dcrm-sdk/wiki) for more information. This SDK allows you to connect to DCRM's network directly in either: 1. a 2+1 configuration where you form a private group with 2 fusion nodes and your own node. 2. a local configuration where you can set any ownership of nodes in your group. This library contains 2 functions: 1. Distributed key generation which returns the public key (dcrm\_genPubkey) 2. Distributed signing of transactions (dcrm\_sign) ## Prerequisites 1. Linux terminal 2. Golang ^1.12 ## Setting Up ### Clone The Repository To get started, launch your terminal and download the latest version of the SDK. ``` mkdir -p $GOPATH/src/github.com/fsn-dev cd $GOPATH/src/github.com/fsn-dev git clone https://github.com/fsn-dev/dcrm-sdk.git ``` ### Build Next compile the code. Make sure you are in /dcrm-sdk directory. ``` cd dcrm-sdk && make ``` ### config file cmd/conf.toml (bin/cmd/conf.toml) ### Run Open access to the APIs by running the compiled code. ``` ./bin/cmd/gdcrm ``` The `gdcrm` will provide two RPC APIs: 1. `dcrm_genPubkey` 2. `dcrm_sign` The default RPC port is port 5559. Note: 1. If you want to call RPC API, please wait at least 2 minutes after running the node. 2. If you want to call RPC API quickly more than once,please wait longer. ## JSON RPC API **dcrm\_genPubkey** This API return a public key which distributed generated by the P2P network's nodes. **Parameters** None **Return** `error` - Error info. `pubkey` - DCRM public key generated by the P2P network's nodes. **Example** ``` // Request curl -X POST -H "Content-Type":application/json --data '{"jsonrpc":"2.0","method":"dcrm_genPubkey","params":[],"id":67}' http://127.0.0.1:5559 // Result { "pubkey":"049ac626ee0f0f79a49d6ed37f14ff2ad4e4f45fddf6e5293bcaa6a607e5392b49dde27a8f0602e23bc5fa0b847bd28d46e2f2d1d0d8cf59514785e4276b28de9d" } ``` **dcrm\_sign** This API return a signature which distributed signed by the P2P network's nodes. **Parameters** 1. `DATA`,pubkey - the pubkey from `dcrm_genPubkey` returned. 2. `String`,HexNumber - the message hash to be signed. The format is 32-bit hexadecimal string appended with prifex "0x".\ For example: 0x19b6236d2e7eb3e925d0c6e8850502c1f04822eb9aa67cb92e5004f7017e5e41. **Return** `error` - Error info. `rsv` - The signature string which distributed signed by the P2P network's nodes. **Example** ``` // Request curl -X POST -H "Content-Type":application/json --data '{"jsonrpc":"2.0","method":"dcrm_sign","params":["049ac626ee0f0f79a49d6ed37f14ff2ad4e4f45fddf6e5293bcaa6a607e5392b49dde27a8f0602e23bc5fa0b847bd28d46e2f2d1d0d8cf59514785e4276b28de9d","0x19b6236d2e7eb3e925d0c6e8850502c1f04822eb9aa67cb92e5004f7017e5e41"],"id":67}' http://127.0.0.1:5559 // Result { "rsv":"FFBB398B95ED2ED308B0FE87BC254FFC2C9957742EA05C18A1411C672B74FBDF6FBD6F4915799F2B4186192581D4506039ADEB79C8EB954E779901FDB9575C8301" } ``` ## Run Local The SDK can also be configured to run locally, where the user can control ownership of all nodes in the P2P network. #### Run bootnode ``` ./bin/cmd/bootnode --genkey ./bootnode.key ./bin/cmd/bootnode --nodekey ./bootnode.key --addr :5550 --group 0 --nodes 3 ``` will print bootnode which use for run node with args --bootnodes bootnode key such as enode://16ab118525ec559dde2640b513676b8df7368aac3a80cc5c9d9e8b9c71781c09103fe3e8b5dd17bf245f0c71b891ec4848b142852763ab2146a1e288df15da40\@127.0.0.1:5550 The default bootnode parameters are: 1. addr: 5550 2. group: 0 (group mode) 3. nodes: 3 (group's nodes number) **Run nodes (3 nodes at least)** The Default setup parameters are: 1. nodekey: node.key 2. rpcport: 5559 3. port: 5551 4. bootnodes: "enode://16ab118525ec559dde2640b513676b8df7368aac3a80cc5c9d9e8b9c71781c09103fe3e8b5dd17bf245f0c71b891ec4848b142852763ab2146a1e288df15da40\@127.0.0.1:5550" Note: If you want to reboot a node, please wait 1 minute after closing node before restarting the node. Setup the node's key: ``` ./bin/cmd/gdcrm ./bin/cmd/gdcrm --genkey node1.key ./bin/cmd/gdcrm --genkey node2.key ./bin/cmd/gdcrm --genkey node3.key ``` Start three nodes with custom parameters: ``` ./bin/cmd/gdcrm --rpcport 9011 --bootnodes "enode://16ab118525ec559dde2640b513676b8df7368aac3a80cc5c9d9e8b9c71781c09103fe3e8b5dd17bf245f0c71b891ec4848b142852763ab2146a1e288df15da40@127.0.0.1:5550" --port 12341 --nodekey "node1.key" ./bin/cmd/gdcrm --rpcport 9012 --bootnodes "enode://16ab118525ec559dde2640b513676b8df7368aac3a80cc5c9d9e8b9c71781c09103fe3e8b5dd17bf245f0c71b891ec4848b142852763ab2146a1e288df15da40@127.0.0.1:5550" --port 12342 --nodekey "node2.key" ./bin/cmd/gdcrm --rpcport 9013 --bootnodes "enode://16ab118525ec559dde2640b513676b8df7368aac3a80cc5c9d9e8b9c71781c09103fe3e8b5dd17bf245f0c71b891ec4848b142852763ab2146a1e288df15da40@127.0.0.1:5550" --port 12343 --nodekey "node3.key" ``` After bootnode and three nodes started, use curl connect to the node's rpc port, test `dcrm_genPubkey` and `dcrm_sign` APIs. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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