Secure-keyword-using-bit-string-signatures-in-Blockchain-
Data privacy is one of the biggest difficulties that every organization faces nowadays. All organizations should provide security protections on personal data against unauthorized access and modifications of any data. Healthcare is such an example where patient data should be handled properly and the leakage or alteration of this data assists in a huge privacy-neglecting issue. Immutability can be provided by adopting the blockchain technology in healthcare. Encryption is a key baseline to data privacy protection. This code introduces a new approach to secure keyword search over encrypted data in the blockchain. In this code, we propose the implementation of the bit-string signatures in the design of a data structure to secure search and access data while hiding the search pattern and share the patient data records between authorized organizations, while ensuring the privacy and im- mutability of the data. Besides, the secure cryptographic protocol - proxy re-encryption is applied to support proper encryption and decryption without revealing the keys and access control over secret data. The goal of this code is the evaluation of the keyword search using bloom filters over encrypted data in the blockchain.