https://github.com/aostrun/notary-public-smart-contract
Smart Contract serving as Notary Public
https://github.com/aostrun/notary-public-smart-contract
ethereum-blockchain ethereum-dapp file-validation smart-contracts solidity
Last synced: about 1 year ago
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Smart Contract serving as Notary Public
- Host: GitHub
- URL: https://github.com/aostrun/notary-public-smart-contract
- Owner: aostrun
- License: apache-2.0
- Created: 2018-04-16T20:35:20.000Z (about 8 years ago)
- Default Branch: master
- Last Pushed: 2018-04-16T21:13:25.000Z (about 8 years ago)
- Last Synced: 2025-02-24T01:50:43.555Z (over 1 year ago)
- Topics: ethereum-blockchain, ethereum-dapp, file-validation, smart-contracts, solidity
- Size: 9.77 KB
- Stars: 1
- Watchers: 3
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
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README
# Notary Public Smart Contract
Smart Contract serving as Notary Public
----------------------------------------------------------------------------
Author: Andrijan Ostrun
April, 2018.
github.com/aostrun
----------------------------------------------------------------------------
Smart Contract serving as Notary Public where you can protect an document
or a file in general by storing it's hash value on the Ethereum blockchain.
Every record besides file hash has parties associated with the record (can be
any number of parties) which can come handy if you are using this as a medium
to store real contracts.
Every party associated with the record has to **accept** it before the record becomes
**valid**. This stands as a protection for all parties involved.
## Use Cases:
* Generally protect file (document) integrity
* Copyright proof on files (pictures, videos, etc.)
## Record Creation
**Creation of new record starts with providing:**
* Hash value of the file that is being protected (*uint256*)
* Hash functions in most cases return hex representation of hash value, **in order to
save that hash value on this Smart Contract you need to convert that string hex representation
into uint256**, so basically turn 2 characters into one byte.
* Recommendation: use at least SHA256 as hashing function
* Parties associated with the record (*address[]*)
* Unix Timestamp for record expiration (*uint256*)
* current timestamp can be found at: https://www.unixtimestamp.com/
* Creation of the record returns unique record ID that has to be remembered by parties
if they want to access that record ever again.
Example of record creation:
`createRecord(2142131241, ["address#1", "address#2", "address#3"], 2523910141)`
Parties accept record by calling function *acceptRecord* from their address.
Function takes record ID as an argument.
## Record Verification
File can be verified by calling *verify* function. Function can be called only from
address that is party on particulat record. Function takes record ID and hash value that
we want to verify as arguments and returns boolean value, true if provided hash value
matches one on the record.
## Record Validity
**Record is valid if:**
* timestamp *validUntil* is greater than current timestamp (time aspect)
* all parties **accepted** the record (party aspect)