pub struct RawMd5Crypt;
use crate::hashes::{AttackModeType, HashModule, HashPattern, ParsedHash};
impl HashModule for RawMd5Crypt {
fn name(&self) -> &'static str { "md5crypt" }
fn mode(&self) -> u32 { 500 }
fn digest_words(&self) -> u32 { 4 }
fn needs_int64(&self) -> bool { false }
fn cpu_verify(&self, password: &str, salt: &[u8], hash: &[u32]) -> bool {
let salt_str = std::str::from_utf8(salt).unwrap_or("");
let full_hash = md5crypt(password, salt_str);
if let Ok(parsed) = self.parse_hash_string(&full_hash) {
parsed.hash_words[..4] == hash[..4]
} else {
false
}
}
fn shader_source(&self, mode: &AttackModeType) -> &'static str {
match mode {
AttackModeType::BruteForce => include_str!("../md5crypt_crack.wgsl"),
AttackModeType::Mask => include_str!("../md5crypt_mask.wgsl"),
AttackModeType::Wordlist => include_str!("../md5crypt_wordlist.wgsl"),
}
}
fn detect_patterns(&self) -> &[HashPattern] {
&[HashPattern { prefix: Some("$1$"), hex_len: None, priority: 50 }]
}
fn parse_hash_string(&self, s: &str) -> Result<ParsedHash, String> {
let s = s.trim();
if !s.starts_with("$1$") {
return Err("Expected $1$ prefix for md5crypt".to_string());
}
let rest = &s[3..];
let parts: Vec<&str> = rest.split('$').collect();
if parts.len() != 2 || parts[1].is_empty() {
return Err(format!("Invalid md5crypt format '{}'. Expected $1$salt$hash", s));
}
let salt_str = parts[0];
if salt_str.len() > 8 {
return Err(format!("md5crypt salt too long (max 8 chars): {}", salt_str.len()));
}
let hash_encoded = parts[1];
if hash_encoded.len() != 22 {
return Err(format!("Expected 22-char md5crypt hash, got {}", hash_encoded.len()));
}
let salt_bytes = salt_str.as_bytes().to_vec();
let hash_bytes = decode_md5crypt_hash(hash_encoded)?;
let mut target = [0u32; 8];
for i in 0..4 {
target[i] = u32::from_le_bytes(hash_bytes[i * 4..i * 4 + 4].try_into().unwrap());
}
Ok(ParsedHash {
hash_words: target,
extra_words: [0u32; 8],
salt: salt_bytes,
digest_words: 4,
})
}
}
const B64: &[u8] = b"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
fn b64_idx(c: u8) -> Option<usize> {
B64.iter().position(|&x| x == c)
}
fn decode_md5crypt_hash(encoded: &str) -> Result<[u8; 16], String> {
let bytes = encoded.as_bytes();
if bytes.len() != 22 {
return Err("md5crypt hash must be 22 chars".to_string());
}
let v: Result<Vec<u8>, String> = bytes.iter().map(|&c| {
b64_idx(c).map(|p| p as u8).ok_or_else(|| format!("Invalid base64 char: {}", c as char))
}).collect();
let v = v?;
let mut out = [0u8; 16];
for i in 0..5 {
let a = v[i * 4] as u32;
let b = v[i * 4 + 1] as u32;
let c = v[i * 4 + 2] as u32;
let d = v[i * 4 + 3] as u32;
let value = a | (b << 6) | (c << 12) | (d << 18);
out[i] = ((value >> 16) & 0xFF) as u8;
out[i + 6] = ((value >> 8) & 0xFF) as u8;
if i < 4 {
out[i + 12] = (value & 0xFF) as u8;
} else {
out[5] = (value & 0xFF) as u8;
}
}
let a = v[20] as u32;
let b = v[21] as u32;
out[11] = (a | (b << 6)) as u8;
Ok(out)
}
pub fn encode_md5crypt_hash(hash: &[u8; 16]) -> String {
let mut out = [0u8; 22];
for i in 0..5 {
let value = (hash[i] as u32) << 16
| (hash[i + 6] as u32) << 8
| if i < 4 { hash[i + 12] as u32 } else { hash[5] as u32 };
out[i * 4] = B64[(value & 0x3F) as usize];
out[i * 4 + 1] = B64[((value >> 6) & 0x3F) as usize];
out[i * 4 + 2] = B64[((value >> 12) & 0x3F) as usize];
out[i * 4 + 3] = B64[((value >> 18) & 0x3F) as usize];
}
let value = hash[11] as u32;
out[20] = B64[(value & 0x3F) as usize];
out[21] = B64[((value >> 6) & 0x3F) as usize];
String::from_utf8(out.to_vec()).unwrap()
}
pub fn md5crypt(password: &str, salt: &str) -> String {
use md5::{Md5, Digest};
let pwd = password.as_bytes();
let salt_bytes = salt.as_bytes();
let mut a_ctx = Md5::new();
a_ctx.update(pwd);
a_ctx.update(b"$1$");
a_ctx.update(salt_bytes);
let mut b_ctx = Md5::new();
b_ctx.update(pwd);
b_ctx.update(salt_bytes);
b_ctx.update(pwd);
let digest_b = b_ctx.finalize();
let mut j = 0;
while j < pwd.len() {
let n = std::cmp::min(pwd.len() - j, 16);
a_ctx.update(&digest_b[..n]);
j += 16;
}
let mut n = pwd.len();
while n > 0 {
if (n & 1) != 0 {
a_ctx.update(&[0u8]);
} else {
a_ctx.update(&[pwd[0]]);
}
n >>= 1;
}
let mut digest = [0u8; 16];
digest.copy_from_slice(&a_ctx.finalize());
for i in 0..1000 {
let mut ctx = Md5::new();
if (i & 1) != 0 {
ctx.update(pwd);
} else {
ctx.update(&digest);
}
if (i % 3) != 0 {
ctx.update(salt_bytes);
}
if (i % 7) != 0 {
ctx.update(pwd);
}
if (i & 1) != 0 {
ctx.update(&digest);
} else {
ctx.update(pwd);
}
let result = ctx.finalize();
digest.copy_from_slice(&result);
}
format!("$1${}${}", salt, encode_md5crypt_hash(&digest))
}
#[test]
fn test_md5crypt_hunter2() {
let hash = md5crypt("hunter2", "1234abcd");
assert_eq!(hash, "$1$1234abcd$k941IFPqhCBpKvhOnZqRd/");
}
#[test]
fn test_md5crypt_roundtrip() {
let module = RawMd5Crypt;
let hash = md5crypt("test123", "abc");
let parsed = module.parse_hash_string(&hash).unwrap();
assert_eq!(parsed.digest_words, 4);
assert_eq!(parsed.salt, b"abc");
}
#[test]
fn test_md5crypt_regression() {
assert_eq!(md5crypt("password", "saltsalt"), "$1$saltsalt$qjXMvbEw8oaL.CzflDtaK/");
assert_eq!(md5crypt("password", "abc"), "$1$abc$BXBqpb9BZcZhXLgbee.0s/");
assert_eq!(md5crypt("test123", "abc"), "$1$abc$0zyr.q.R6J8FreshPZmKj.");
assert_eq!(md5crypt("test", ""), "$1$$whuMjZj.HMFoaTaZRRtkO0");
}