Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

ensure that we require enough shares #4

Merged
merged 1 commit into from
Jan 21, 2020
Merged
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
127 changes: 70 additions & 57 deletions src/lib.rs
Original file line number Diff line number Diff line change
@@ -1,6 +1,6 @@
extern crate rand;

use rand::{Rng, thread_rng};
use rand::{thread_rng, Rng};

#[cfg(test)]
mod tests {
Expand Down Expand Up @@ -74,6 +74,29 @@ mod tests {

assert_eq!(&new_secret[..], "Hello, world!");
}

#[test]
fn it_requires_enough_shares() {
fn try_recover(n: u8, shares: &Vec<Vec<u8>>) -> Option<String> {
let shares = shares.iter().take(n as usize).cloned().collect::<Vec<_>>();
SecretData::recover_secret(n, shares)
}
let secret_data = SecretData::with_secret("Hello World!", 5);

let shares = vec![
secret_data.get_share(1),
secret_data.get_share(2),
secret_data.get_share(3),
secret_data.get_share(4),
secret_data.get_share(5),
];

let recovered = try_recover(5, &shares);
assert!(recovered.is_some());

let recovered = try_recover(3, &shares);
assert!(recovered.is_none());
}
}

pub struct SecretData {
Expand All @@ -86,7 +109,7 @@ impl SecretData {
pub fn with_secret(secret: &str, threshold: u8) -> SecretData {
let mut coefficients: Vec<Vec<u8>> = vec![];
let mut rng = thread_rng();
let mut rand_container = [0u8, threshold - 1];
let mut rand_container = vec![0u8; (threshold - 1) as usize];
for c in secret.as_bytes() {
rng.fill_bytes(&mut rand_container);
let mut coef: Vec<u8> = vec![*c];
Expand Down Expand Up @@ -201,8 +224,10 @@ impl SecretData {
}

let denominator = SecretData::gf256_sub(&xs[i], &xs[j]);
let this_term = vec![SecretData::gf256_div(&xs[j], &denominator),
SecretData::gf256_div(&1, &denominator)];
let this_term = vec![
SecretData::gf256_div(&xs[j], &denominator),
SecretData::gf256_div(&1, &denominator),
];

this_polynomial = SecretData::multiply_polynomials(&this_polynomial, &this_term);
// panic!("wait");
Expand All @@ -211,8 +236,8 @@ impl SecretData {
this_polynomial = SecretData::multiply_polynomials(&this_polynomial, &vec![fxs[i]])
}
// this_polynomial = _multiply_polynomials(this_polynomial, [fxs[i]]) if fxs[i]
returned_coefficients = SecretData::add_polynomials(&returned_coefficients,
&this_polynomial);
returned_coefficients =
SecretData::add_polynomials(&returned_coefficients, &this_polynomial);
// returnedcoefficients = _add_polynomials(returnedcoefficients, this_polynomial)
}
returned_coefficients
Expand All @@ -233,8 +258,8 @@ impl SecretData {
if *a == 0 || *b == 0 {
0
} else {
GF256_EXP[((GF256_LOG[*a as usize] as u16 + GF256_LOG[*b as usize] as u16) %
255) as usize]
GF256_EXP
[((GF256_LOG[*a as usize] as u16 + GF256_LOG[*b as usize] as u16) % 255) as usize]
}
}

Expand Down Expand Up @@ -293,52 +318,40 @@ impl SecretData {
results
}
}
static GF256_EXP: [u8; 256] = [0x01, 0x03, 0x05, 0x0f, 0x11, 0x33, 0x55, 0xff, 0x1a, 0x2e, 0x72,
0x96, 0xa1, 0xf8, 0x13, 0x35, 0x5f, 0xe1, 0x38, 0x48, 0xd8, 0x73,
0x95, 0xa4, 0xf7, 0x02, 0x06, 0x0a, 0x1e, 0x22, 0x66, 0xaa, 0xe5,
0x34, 0x5c, 0xe4, 0x37, 0x59, 0xeb, 0x26, 0x6a, 0xbe, 0xd9, 0x70,
0x90, 0xab, 0xe6, 0x31, 0x53, 0xf5, 0x04, 0x0c, 0x14, 0x3c, 0x44,
0xcc, 0x4f, 0xd1, 0x68, 0xb8, 0xd3, 0x6e, 0xb2, 0xcd, 0x4c, 0xd4,
0x67, 0xa9, 0xe0, 0x3b, 0x4d, 0xd7, 0x62, 0xa6, 0xf1, 0x08, 0x18,
0x28, 0x78, 0x88, 0x83, 0x9e, 0xb9, 0xd0, 0x6b, 0xbd, 0xdc, 0x7f,
0x81, 0x98, 0xb3, 0xce, 0x49, 0xdb, 0x76, 0x9a, 0xb5, 0xc4, 0x57,
0xf9, 0x10, 0x30, 0x50, 0xf0, 0x0b, 0x1d, 0x27, 0x69, 0xbb, 0xd6,
0x61, 0xa3, 0xfe, 0x19, 0x2b, 0x7d, 0x87, 0x92, 0xad, 0xec, 0x2f,
0x71, 0x93, 0xae, 0xe9, 0x20, 0x60, 0xa0, 0xfb, 0x16, 0x3a, 0x4e,
0xd2, 0x6d, 0xb7, 0xc2, 0x5d, 0xe7, 0x32, 0x56, 0xfa, 0x15, 0x3f,
0x41, 0xc3, 0x5e, 0xe2, 0x3d, 0x47, 0xc9, 0x40, 0xc0, 0x5b, 0xed,
0x2c, 0x74, 0x9c, 0xbf, 0xda, 0x75, 0x9f, 0xba, 0xd5, 0x64, 0xac,
0xef, 0x2a, 0x7e, 0x82, 0x9d, 0xbc, 0xdf, 0x7a, 0x8e, 0x89, 0x80,
0x9b, 0xb6, 0xc1, 0x58, 0xe8, 0x23, 0x65, 0xaf, 0xea, 0x25, 0x6f,
0xb1, 0xc8, 0x43, 0xc5, 0x54, 0xfc, 0x1f, 0x21, 0x63, 0xa5, 0xf4,
0x07, 0x09, 0x1b, 0x2d, 0x77, 0x99, 0xb0, 0xcb, 0x46, 0xca, 0x45,
0xcf, 0x4a, 0xde, 0x79, 0x8b, 0x86, 0x91, 0xa8, 0xe3, 0x3e, 0x42,
0xc6, 0x51, 0xf3, 0x0e, 0x12, 0x36, 0x5a, 0xee, 0x29, 0x7b, 0x8d,
0x8c, 0x8f, 0x8a, 0x85, 0x94, 0xa7, 0xf2, 0x0d, 0x17, 0x39, 0x4b,
0xdd, 0x7c, 0x84, 0x97, 0xa2, 0xfd, 0x1c, 0x24, 0x6c, 0xb4, 0xc7,
0x52, 0xf6, 0x01];

static GF256_LOG: [u8; 256] = [0x00, 0x00, 0x19, 0x01, 0x32, 0x02, 0x1a, 0xc6, 0x4b, 0xc7, 0x1b,
0x68, 0x33, 0xee, 0xdf, 0x03, 0x64, 0x04, 0xe0, 0x0e, 0x34, 0x8d,
0x81, 0xef, 0x4c, 0x71, 0x08, 0xc8, 0xf8, 0x69, 0x1c, 0xc1, 0x7d,
0xc2, 0x1d, 0xb5, 0xf9, 0xb9, 0x27, 0x6a, 0x4d, 0xe4, 0xa6, 0x72,
0x9a, 0xc9, 0x09, 0x78, 0x65, 0x2f, 0x8a, 0x05, 0x21, 0x0f, 0xe1,
0x24, 0x12, 0xf0, 0x82, 0x45, 0x35, 0x93, 0xda, 0x8e, 0x96, 0x8f,
0xdb, 0xbd, 0x36, 0xd0, 0xce, 0x94, 0x13, 0x5c, 0xd2, 0xf1, 0x40,
0x46, 0x83, 0x38, 0x66, 0xdd, 0xfd, 0x30, 0xbf, 0x06, 0x8b, 0x62,
0xb3, 0x25, 0xe2, 0x98, 0x22, 0x88, 0x91, 0x10, 0x7e, 0x6e, 0x48,
0xc3, 0xa3, 0xb6, 0x1e, 0x42, 0x3a, 0x6b, 0x28, 0x54, 0xfa, 0x85,
0x3d, 0xba, 0x2b, 0x79, 0x0a, 0x15, 0x9b, 0x9f, 0x5e, 0xca, 0x4e,
0xd4, 0xac, 0xe5, 0xf3, 0x73, 0xa7, 0x57, 0xaf, 0x58, 0xa8, 0x50,
0xf4, 0xea, 0xd6, 0x74, 0x4f, 0xae, 0xe9, 0xd5, 0xe7, 0xe6, 0xad,
0xe8, 0x2c, 0xd7, 0x75, 0x7a, 0xeb, 0x16, 0x0b, 0xf5, 0x59, 0xcb,
0x5f, 0xb0, 0x9c, 0xa9, 0x51, 0xa0, 0x7f, 0x0c, 0xf6, 0x6f, 0x17,
0xc4, 0x49, 0xec, 0xd8, 0x43, 0x1f, 0x2d, 0xa4, 0x76, 0x7b, 0xb7,
0xcc, 0xbb, 0x3e, 0x5a, 0xfb, 0x60, 0xb1, 0x86, 0x3b, 0x52, 0xa1,
0x6c, 0xaa, 0x55, 0x29, 0x9d, 0x97, 0xb2, 0x87, 0x90, 0x61, 0xbe,
0xdc, 0xfc, 0xbc, 0x95, 0xcf, 0xcd, 0x37, 0x3f, 0x5b, 0xd1, 0x53,
0x39, 0x84, 0x3c, 0x41, 0xa2, 0x6d, 0x47, 0x14, 0x2a, 0x9e, 0x5d,
0x56, 0xf2, 0xd3, 0xab, 0x44, 0x11, 0x92, 0xd9, 0x23, 0x20, 0x2e,
0x89, 0xb4, 0x7c, 0xb8, 0x26, 0x77, 0x99, 0xe3, 0xa5, 0x67, 0x4a,
0xed, 0xde, 0xc5, 0x31, 0xfe, 0x18, 0x0d, 0x63, 0x8c, 0x80, 0xc0,
0xf7, 0x70, 0x07];
static GF256_EXP: [u8; 256] = [
0x01, 0x03, 0x05, 0x0f, 0x11, 0x33, 0x55, 0xff, 0x1a, 0x2e, 0x72, 0x96, 0xa1, 0xf8, 0x13, 0x35,
0x5f, 0xe1, 0x38, 0x48, 0xd8, 0x73, 0x95, 0xa4, 0xf7, 0x02, 0x06, 0x0a, 0x1e, 0x22, 0x66, 0xaa,
0xe5, 0x34, 0x5c, 0xe4, 0x37, 0x59, 0xeb, 0x26, 0x6a, 0xbe, 0xd9, 0x70, 0x90, 0xab, 0xe6, 0x31,
0x53, 0xf5, 0x04, 0x0c, 0x14, 0x3c, 0x44, 0xcc, 0x4f, 0xd1, 0x68, 0xb8, 0xd3, 0x6e, 0xb2, 0xcd,
0x4c, 0xd4, 0x67, 0xa9, 0xe0, 0x3b, 0x4d, 0xd7, 0x62, 0xa6, 0xf1, 0x08, 0x18, 0x28, 0x78, 0x88,
0x83, 0x9e, 0xb9, 0xd0, 0x6b, 0xbd, 0xdc, 0x7f, 0x81, 0x98, 0xb3, 0xce, 0x49, 0xdb, 0x76, 0x9a,
0xb5, 0xc4, 0x57, 0xf9, 0x10, 0x30, 0x50, 0xf0, 0x0b, 0x1d, 0x27, 0x69, 0xbb, 0xd6, 0x61, 0xa3,
0xfe, 0x19, 0x2b, 0x7d, 0x87, 0x92, 0xad, 0xec, 0x2f, 0x71, 0x93, 0xae, 0xe9, 0x20, 0x60, 0xa0,
0xfb, 0x16, 0x3a, 0x4e, 0xd2, 0x6d, 0xb7, 0xc2, 0x5d, 0xe7, 0x32, 0x56, 0xfa, 0x15, 0x3f, 0x41,
0xc3, 0x5e, 0xe2, 0x3d, 0x47, 0xc9, 0x40, 0xc0, 0x5b, 0xed, 0x2c, 0x74, 0x9c, 0xbf, 0xda, 0x75,
0x9f, 0xba, 0xd5, 0x64, 0xac, 0xef, 0x2a, 0x7e, 0x82, 0x9d, 0xbc, 0xdf, 0x7a, 0x8e, 0x89, 0x80,
0x9b, 0xb6, 0xc1, 0x58, 0xe8, 0x23, 0x65, 0xaf, 0xea, 0x25, 0x6f, 0xb1, 0xc8, 0x43, 0xc5, 0x54,
0xfc, 0x1f, 0x21, 0x63, 0xa5, 0xf4, 0x07, 0x09, 0x1b, 0x2d, 0x77, 0x99, 0xb0, 0xcb, 0x46, 0xca,
0x45, 0xcf, 0x4a, 0xde, 0x79, 0x8b, 0x86, 0x91, 0xa8, 0xe3, 0x3e, 0x42, 0xc6, 0x51, 0xf3, 0x0e,
0x12, 0x36, 0x5a, 0xee, 0x29, 0x7b, 0x8d, 0x8c, 0x8f, 0x8a, 0x85, 0x94, 0xa7, 0xf2, 0x0d, 0x17,
0x39, 0x4b, 0xdd, 0x7c, 0x84, 0x97, 0xa2, 0xfd, 0x1c, 0x24, 0x6c, 0xb4, 0xc7, 0x52, 0xf6, 0x01,
];

static GF256_LOG: [u8; 256] = [
0x00, 0x00, 0x19, 0x01, 0x32, 0x02, 0x1a, 0xc6, 0x4b, 0xc7, 0x1b, 0x68, 0x33, 0xee, 0xdf, 0x03,
0x64, 0x04, 0xe0, 0x0e, 0x34, 0x8d, 0x81, 0xef, 0x4c, 0x71, 0x08, 0xc8, 0xf8, 0x69, 0x1c, 0xc1,
0x7d, 0xc2, 0x1d, 0xb5, 0xf9, 0xb9, 0x27, 0x6a, 0x4d, 0xe4, 0xa6, 0x72, 0x9a, 0xc9, 0x09, 0x78,
0x65, 0x2f, 0x8a, 0x05, 0x21, 0x0f, 0xe1, 0x24, 0x12, 0xf0, 0x82, 0x45, 0x35, 0x93, 0xda, 0x8e,
0x96, 0x8f, 0xdb, 0xbd, 0x36, 0xd0, 0xce, 0x94, 0x13, 0x5c, 0xd2, 0xf1, 0x40, 0x46, 0x83, 0x38,
0x66, 0xdd, 0xfd, 0x30, 0xbf, 0x06, 0x8b, 0x62, 0xb3, 0x25, 0xe2, 0x98, 0x22, 0x88, 0x91, 0x10,
0x7e, 0x6e, 0x48, 0xc3, 0xa3, 0xb6, 0x1e, 0x42, 0x3a, 0x6b, 0x28, 0x54, 0xfa, 0x85, 0x3d, 0xba,
0x2b, 0x79, 0x0a, 0x15, 0x9b, 0x9f, 0x5e, 0xca, 0x4e, 0xd4, 0xac, 0xe5, 0xf3, 0x73, 0xa7, 0x57,
0xaf, 0x58, 0xa8, 0x50, 0xf4, 0xea, 0xd6, 0x74, 0x4f, 0xae, 0xe9, 0xd5, 0xe7, 0xe6, 0xad, 0xe8,
0x2c, 0xd7, 0x75, 0x7a, 0xeb, 0x16, 0x0b, 0xf5, 0x59, 0xcb, 0x5f, 0xb0, 0x9c, 0xa9, 0x51, 0xa0,
0x7f, 0x0c, 0xf6, 0x6f, 0x17, 0xc4, 0x49, 0xec, 0xd8, 0x43, 0x1f, 0x2d, 0xa4, 0x76, 0x7b, 0xb7,
0xcc, 0xbb, 0x3e, 0x5a, 0xfb, 0x60, 0xb1, 0x86, 0x3b, 0x52, 0xa1, 0x6c, 0xaa, 0x55, 0x29, 0x9d,
0x97, 0xb2, 0x87, 0x90, 0x61, 0xbe, 0xdc, 0xfc, 0xbc, 0x95, 0xcf, 0xcd, 0x37, 0x3f, 0x5b, 0xd1,
0x53, 0x39, 0x84, 0x3c, 0x41, 0xa2, 0x6d, 0x47, 0x14, 0x2a, 0x9e, 0x5d, 0x56, 0xf2, 0xd3, 0xab,
0x44, 0x11, 0x92, 0xd9, 0x23, 0x20, 0x2e, 0x89, 0xb4, 0x7c, 0xb8, 0x26, 0x77, 0x99, 0xe3, 0xa5,
0x67, 0x4a, 0xed, 0xde, 0xc5, 0x31, 0xfe, 0x18, 0x0d, 0x63, 0x8c, 0x80, 0xc0, 0xf7, 0x70, 0x07,
];