Hermes: Efficient and Secure Multi-Writer Encrypted Database

This is our full implementation for our [Hermes paper].

WARNING: This is an academic proof-of-concept prototype and has not received careful code review. This implementation is NOT ready for production use.

Required Libraries

1. GMP

2. PBC

3. ZeroMQ

4. EMP-Toolkit

You can run the script file auto_setup.sh to automatically install the required libraries.

./auto_setup.sh

Dataset

Download Enron email dataset at: https://www.cs.cmu.edu/~enron/, then extract to obtain maildir folder. Put file extract_database.go on the same hierarchy level as maildir. Next, execute extract_database.go to obtain folder database as follows, then move it into Hermes on the same level as folders server and client.

go env -w GO111MODULE=off 
go get github.com/montanaflynn/stats
go run extract_database.go

Build & Compile

Go to the folder Hermes then execute:

make clean
make

This is going to create executable files server in server folder and client in client folder.

Testing

1. Launch server:

cd server
./server [<Number_of_Writers>]

For example, we launch server with 150 writers:

./server 150

By default without an input parameter, the server is initialized with 25 writers.

2. Launch client:

For keyword search:

cd client
./client -s [<keyword>] [<writer_subset_size>] 

For keyword update:

cd client
./client -u [<number_of_updates>]

For example:

./client -s university 150    // Search keyword "university" over databases of 150 writers

./client -u 150               // Update 150 new keywords

NOTE: We only need to start server one time.

Enable Hermes⁺

Uncomment the line 21 #define SEARCH_EFFICIENCY 1 in file config.hpp and recompile.

Configuring Number of Threads

Change the constants defined at lines 4 and 5: const int MAX_THREADS_INIT = 8; and const int MAX_THREADS_SEARCH = 8; in file config.hpp and recompile server.

make server

Configuring Server IP Address

To run experiments with a remote server, we need to change the IP loopback 127.0.0.1 to the IP address of the server as follows.

Modify the server's IP address at line 682 string server_address = "tcp://127.0.0.1:" + to_string(SERVER_PORT); in file client/client.cpp and recompile client.

make client

Citing

If the code is found useful, we would be appreciated if our paper can be cited with the following bibtex format:

@inproceedings{le2025hermes,
author = {Le, Tung and  Hoang, Thang},
title = {{Hermes: Efficient and Secure Multi-Writer Encrypted Database}},
booktitle = {46th IEEE Symposium on Security and Privacy (IEEE S&P 2025)},
year = {2025},
address = {San Francisco, CA, USA},
month = {May},
year = {2025}
}

Further Information

For any inquiries, bugs, and assistance on building and running the code, please contact me at tungle@vt.edu.