ftie-cp

Compile Instruction

g++ -o bin/ftie-cli -std=c++17 ftie/*.h ftie/*.cpp main.cpp `libpng-config --ldflags` -lgmpxx -lgmp

On macOS with Homebrew, Clang doesn't search /opt/homebrew by default and also errors on the ftie/*.h glob when treated as separate translation units, so use instead:

g++ -o bin/ftie-cli -std=c++17 -I/opt/homebrew/include -L/opt/homebrew/lib ftie/*.cpp main.cpp `libpng-config --cflags --ldflags` -lgmpxx -lgmp

Requirements

• g++ (Ubuntu 8-20180424-0ubuntu1~16.04.1) 8.0.1 20180424 (experimental) [trunk revision 259590]
• png++-0.2.9
• gmp/gmpxx (arbitrary-precision arithmetic for the BBS modulus) — brew install gmp on macOS, or the libgmp-dev package on Linux.

Generating BBS primes

P/Q need to be ~1024-bit primes congruent to 3 mod 4 (so the BBS modulus P*Q is ~2048 bits). Generate one at a time:

./bin/ftie-cli genprime 1024

Run it twice to get distinct P and Q, then pass the printed decimal values as CLI args to encrypt/decrypt.

System Block Diagram

Experiment Environment

aws ec2 create-security-group --group-name 'launch-wizard-1' --description 'launch-wizard-1 created 2026-08-30T08:25:41.152Z' --vpc-id 'vpc-00df7112eceed7a46' 
aws ec2 authorize-security-group-ingress --group-id 'sg-preview-1' --ip-permissions '{"IpProtocol":"tcp","FromPort":22,"ToPort":22,"IpRanges":[{"CidrIp":"0.0.0.0/0"}]}' 
aws ec2 run-instances --image-id 'ami-0f8a61b66d1accaee' --instance-type 'c7i.large' --ebs-optimized --block-device-mappings '{"DeviceName":"/dev/sda1","Ebs":{"Encrypted":false,"DeleteOnTermination":true,"Iops":3000,"SnapshotId":"snap-0cc002ff6c0b55ad2","VolumeSize":20,"VolumeType":"gp3","Throughput":125}}' --network-interfaces '{"AssociatePublicIpAddress":true,"DeviceIndex":0,"Groups":["sg-preview-1"]}' --metadata-options '{"HttpEndpoint":"enabled","HttpPutResponseHopLimit":2,"HttpTokens":"required"}' --private-dns-name-options '{"HostnameType":"ip-name","EnableResourceNameDnsARecord":true,"EnableResourceNameDnsAAAARecord":false}' --count '1' 

Deprecated System Block Diagram [1]