use crate::prelude::*;
use hmac::Mac as _;
use sha1::Digest as _;
fn hkdf_expand_sha256(prk: &[u8], info: &[u8], out: &mut [u8]) -> Result<()> {
const HASH_LEN: usize = 32;
if out.len() > 255 * HASH_LEN {
return Err(Error::HkdfExpand);
}
let mut prev: [u8; HASH_LEN] = [0; HASH_LEN];
let mut prev_len = 0;
let mut counter: u8 = 1;
let mut offset = 0;
while offset < out.len() {
let mut mac = hmac::Hmac::<sha2::Sha256>::new_from_slice(prk)
.map_err(|_| Error::HkdfExpand)?;
mac.update(&prev[..prev_len]);
mac.update(info);
mac.update(&[counter]);
let block = mac.finalize().into_bytes();
let take = (out.len() - offset).min(HASH_LEN);
out[offset..offset + take].copy_from_slice(&block[..take]);
prev.copy_from_slice(&block);
prev_len = HASH_LEN;
offset += take;
counter = counter.wrapping_add(1);
}
Ok(())
}
pub struct Identity {
pub email: String,
pub keys: crate::locked::Keys,
pub master_password_hash: crate::locked::PasswordHash,
}
impl Identity {
pub fn new(
email: &str,
password: &crate::locked::Password,
kdf: crate::api::KdfType,
iterations: u32,
memory: Option<u32>,
parallelism: Option<u32>,
) -> Result<Self> {
let email = email.trim().to_lowercase();
let iterations = std::num::NonZeroU32::new(iterations)
.ok_or(Error::Pbkdf2ZeroIterations)?;
let mut keys = crate::locked::Vec::new();
keys.extend(std::iter::repeat_n(0, 64));
let enc_key = &mut keys.data_mut()[0..32];
match kdf {
crate::api::KdfType::Pbkdf2 => {
pbkdf2::pbkdf2::<hmac::Hmac<sha2::Sha256>>(
password.password(),
email.as_bytes(),
iterations.get(),
enc_key,
)
.map_err(|_| Error::Pbkdf2)?;
}
crate::api::KdfType::Argon2id => {
let mut hasher = sha2::Sha256::new();
hasher.update(email.as_bytes());
let salt = hasher.finalize();
let argon2_config = argon2::Argon2::new(
argon2::Algorithm::Argon2id,
argon2::Version::V0x13,
argon2::Params::new(
memory.unwrap() * 1024,
iterations.get(),
parallelism.unwrap(),
Some(32),
)
.unwrap(),
);
argon2::Argon2::hash_password_into(
&argon2_config,
password.password(),
&salt,
enc_key,
)
.map_err(|_| Error::Argon2)?;
}
}
let mut hash = crate::locked::Vec::new();
hash.extend(std::iter::repeat_n(0, 32));
pbkdf2::pbkdf2::<hmac::Hmac<sha2::Sha256>>(
enc_key,
password.password(),
1,
hash.data_mut(),
)
.map_err(|_| Error::Pbkdf2)?;
let mut prk: [u8; 32] = [0; 32];
prk.copy_from_slice(enc_key);
hkdf_expand_sha256(&prk, b"enc", enc_key)?;
let mac_key = &mut keys.data_mut()[32..64];
hkdf_expand_sha256(&prk, b"mac", mac_key)?;
let keys = crate::locked::Keys::new(keys);
let master_password_hash = crate::locked::PasswordHash::new(hash);
Ok(Self {
email: email.clone(),
keys,
master_password_hash,
})
}
}
#[test]
fn test_hkdf_expand_sha256_rfc5869_a1() {
let prk: [u8; 32] = [
0x07, 0x77, 0x09, 0x36, 0x2c, 0x2e, 0x32, 0xdf, 0x0d, 0xdc, 0x3f,
0x0d, 0xc4, 0x7b, 0xba, 0x63, 0x90, 0xb6, 0xc7, 0x3b, 0xb5, 0x0f,
0x9c, 0x31, 0x22, 0xec, 0x84, 0x4a, 0xd7, 0xc2, 0xb3, 0xe5,
];
let info: [u8; 10] =
[0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9];
let expected: [u8; 42] = [
0x3c, 0xb2, 0x5f, 0x25, 0xfa, 0xac, 0xd5, 0x7a, 0x90, 0x43, 0x4f,
0x64, 0xd0, 0x36, 0x2f, 0x2a, 0x2d, 0x2d, 0x0a, 0x90, 0xcf, 0x1a,
0x5a, 0x4c, 0x5d, 0xb0, 0x2d, 0x56, 0xec, 0xc4, 0xc5, 0xbf, 0x34,
0x00, 0x72, 0x08, 0xd5, 0xb8, 0x87, 0x18, 0x58, 0x65,
];
let mut out = [0_u8; 42];
hkdf_expand_sha256(&prk, &info, &mut out).unwrap();
assert_eq!(out, expected);
}
#[test]
fn test_hkdf_expand_sha256_rfc5869_a2() {
let prk: [u8; 32] = [
0x06, 0xa6, 0xb8, 0x8c, 0x58, 0x53, 0x36, 0x1a, 0x06, 0x10, 0x4c,
0x9c, 0xeb, 0x35, 0xb4, 0x5c, 0xef, 0x76, 0x00, 0x14, 0x90, 0x46,
0x71, 0x01, 0x4a, 0x19, 0x3f, 0x40, 0xc1, 0x5f, 0xc2, 0x44,
];
let info: [u8; 80] = [
0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba,
0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5,
0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 0xd0,
0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb,
0xdc, 0xdd, 0xde, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6,
0xe7, 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, 0xf0, 0xf1,
0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfc,
0xfd, 0xfe, 0xff,
];
let expected: [u8; 82] = [
0xb1, 0x1e, 0x39, 0x8d, 0xc8, 0x03, 0x27, 0xa1, 0xc8, 0xe7, 0xf7,
0x8c, 0x59, 0x6a, 0x49, 0x34, 0x4f, 0x01, 0x2e, 0xda, 0x2d, 0x4e,
0xfa, 0xd8, 0xa0, 0x50, 0xcc, 0x4c, 0x19, 0xaf, 0xa9, 0x7c, 0x59,
0x04, 0x5a, 0x99, 0xca, 0xc7, 0x82, 0x72, 0x71, 0xcb, 0x41, 0xc6,
0x5e, 0x59, 0x0e, 0x09, 0xda, 0x32, 0x75, 0x60, 0x0c, 0x2f, 0x09,
0xb8, 0x36, 0x77, 0x93, 0xa9, 0xac, 0xa3, 0xdb, 0x71, 0xcc, 0x30,
0xc5, 0x81, 0x79, 0xec, 0x3e, 0x87, 0xc1, 0x4c, 0x01, 0xd5, 0xc1,
0xf3, 0x43, 0x4f, 0x1d, 0x87,
];
let mut out = [0_u8; 82];
hkdf_expand_sha256(&prk, &info, &mut out).unwrap();
assert_eq!(out, expected);
}
#[test]
fn test_hkdf_expand_sha256_rfc5869_a3() {
let prk: [u8; 32] = [
0x19, 0xef, 0x24, 0xa3, 0x2c, 0x71, 0x7b, 0x16, 0x7f, 0x33, 0xa9,
0x1d, 0x6f, 0x64, 0x8b, 0xdf, 0x96, 0x59, 0x67, 0x76, 0xaf, 0xdb,
0x63, 0x77, 0xac, 0x43, 0x4c, 0x1c, 0x29, 0x3c, 0xcb, 0x04,
];
let expected: [u8; 42] = [
0x8d, 0xa4, 0xe7, 0x75, 0xa5, 0x63, 0xc1, 0x8f, 0x71, 0x5f, 0x80,
0x2a, 0x06, 0x3c, 0x5a, 0x31, 0xb8, 0xa1, 0x1f, 0x5c, 0x5e, 0xe1,
0x87, 0x9e, 0xc3, 0x45, 0x4e, 0x5f, 0x3c, 0x73, 0x8d, 0x2d, 0x9d,
0x20, 0x13, 0x95, 0xfa, 0xa4, 0xb6, 0x1a, 0x96, 0xc8,
];
let mut out = [0_u8; 42];
hkdf_expand_sha256(&prk, &[], &mut out).unwrap();
assert_eq!(out, expected);
}
#[test]
fn test_hkdf_expand_sha256_rejects_oversize_output() {
let prk = [0u8; 32];
let mut out = vec![0_u8; 8161];
assert!(hkdf_expand_sha256(&prk, &[], &mut out).is_err());
}