FheString

A Fully Homomorphic String library written in Rust using Zama's tfhe-rs.

How it works

The binary given is not meant for production use but rather a proof of concept on how a FHE String library would work. The program takes as cli arguments the string, pattern, n, from and to and runs all supported algorithms and compares their results with the standard string library in Rust. It outputs the time it took as well as if the results match.

Supported String functions

The supported string functions are the following:

• contains with clear / encrypted pattern
• ends_with with clear pattern / encrypted pattern
• eq_ignore_case
• find with clear pattern / encrypted pattern
• is_empty
• len
• repeat with clear / encrypted number of repetitions
• replace with clear pattern / encrypted pattern
• replacen with clear pattern / encrypted pattern
• rfind with clear pattern / encrypted pattern
• rsplit with clear pattern / encrypted pattern
• rsplit_once with clear pattern / encrypted pattern
• rsplitn with clear pattern / encrypted pattern
• rsplit_terminator with clear pattern / encrypted pattern
• split with clear pattern / encrypted pattern
• split_ascii_whitespace
• split_inclusive with clear pattern / encrypted pattern
• split_terminator with clear pattern / encrypted pattern
• splitn with clear pattern / encrypted pattern
• starts_with with clear pattern / encrypted pattern
• strip_prefix with clear pattern / encrypted pattern
• strip_suffix with clear pattern / encrypted pattern
• to_lowercase
• to_uppercase
• trim
• trim_end
• trim_start
• + (concatenation)
• Comparisons between strings >=, <=, !=, ==

Buidling

cargo b --release

Example input

$ fhestring --string "hello" --pattern "ello" --n 1 --from "ello" --to "_llo"

Cli Arguments

$ fhestring --help
    Finished release [optimized] target(s) in 0.08s
     Running `target/release/fhestring --help`
A FHE string implementation using tfhe-rs

Usage: fhestring --string <STRING> --pattern <PATTERN> --n <N> --from <FROM> --to <TO>

Options:
  -s, --string <STRING>    The string to do the processing on
  -p, --pattern <PATTERN>  The pattern for the algoritmhs that need it
  -n, --n <N>              The number of times to make an operation for the algoritmhs that need it
  -f, --from <FROM>        What will be replaced (for replace algorithms)
  -t, --to <TO>            What will replace it (for replace algorithms)
  -h, --help               Print help
  -V, --version            Print version