use std::char;
use std::str::from_utf8;
use crate::error::Error;
use super::Result;
const CRYPT_HASH64: &[u8] = b"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
const CRYPT_HASH64_ENC_MAP: &[u8] = b"\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x00\x01\
\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x40\x40\x40\x40\x40\x40\
\x40\x0c\x0d\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\
\x1b\x1c\x1d\x1e\x1f\x20\x21\x22\x23\x24\x25\x40\x40\x40\x40\x40\
\x40\x26\x27\x28\x29\x2a\x2b\x2c\x2d\x2e\x2f\x30\x31\x32\x33\x34\
\x35\x36\x37\x38\x39\x3a\x3b\x3c\x3d\x3e\x3f\x40\x40\x40\x40\x40";
const BCRYPT_HASH64: &[u8] = b"./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
const BCRYPT_HASH64_ENC_MAP: &[u8] = b"\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x40\x00\x01\
\x36\x37\x38\x39\x3a\x3b\x3c\x3d\x3e\x3f\x40\x40\x40\x40\x40\x40\
\x40\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10\
\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x40\x40\x40\x40\x40\
\x40\x1c\x1d\x1e\x1f\x20\x21\x22\x23\x24\x25\x26\x27\x28\x29\x2a\
\x2b\x2c\x2d\x2e\x2f\x30\x31\x32\x33\x34\x35\x40\x40\x40\x40\x40";
pub fn bcrypt_hash64_decode(enc: &str, decbuf: &mut [u8]) -> Result<()> {
let mut cbuild = 0u8;
let mut cpos = 0;
let mut dec_idx = 0;
for b in enc.chars() {
let b = b as u32 - 0x20;
if b > 0x60 {
return Err(Error::EncodingError);
}
let dec = BCRYPT_HASH64_ENC_MAP[b as usize];
if dec == 64 {
return Err(Error::EncodingError);
}
if cpos == 0 {
cbuild = dec;
} else {
cbuild <<= cpos;
cbuild |= dec >> (6 - cpos);
decbuf[dec_idx] = cbuild;
dec_idx += 1;
if dec_idx == decbuf.len() {
break;
}
cbuild = dec & (0x3F >> cpos);
}
cpos += 2;
if cpos > 6 {
cpos = 0;
}
}
Ok(())
}
pub fn bcrypt_hash64_encode(bs: &[u8]) -> String {
b_c_hash64_encode(bs, &BCRYPT_HASH64)
}
pub fn crypt_hash64_encode(bs: &[u8]) -> String {
b_c_hash64_encode(bs, &CRYPT_HASH64)
}
fn b_c_hash64_encode(bs: &[u8], hs: &[u8]) -> String {
let ngroups = (bs.len() + 2) / 3;
let mut out = String::with_capacity(ngroups * 4);
for g in 0..ngroups {
let mut g_idx = g * 3;
let mut enc = 0u32;
for _ in 0..3 {
let b = (if g_idx < bs.len() { bs[g_idx] } else { 0 }) as u32;
enc <<= 8;
enc |= b;
g_idx += 1;
}
for _ in 0..4 {
out.push(char::from_u32(hs[((enc >> 18) & 0x3F) as usize] as u32).unwrap());
enc <<= 6;
}
}
match bs.len() % 3 {
1 => { out.pop(); out.pop(); },
2 => { out.pop(); },
_ => (),
}
out
}
const SHA1_HASH_LEN: usize = 20;
pub fn sha1crypt_hash64_encode(bs: &[u8]) -> String {
assert!(bs.len() >= SHA1_HASH_LEN);
let ngroups = (SHA1_HASH_LEN + 2) / 3;
let mut out = String::with_capacity(ngroups * 4);
for g in 0..ngroups {
let mut g_idx = g * 3;
let mut enc: u32 = 0;
for _ in 0..3 {
let b = (if g_idx < SHA1_HASH_LEN { bs[g_idx] } else { bs[0] }) as u32;
enc <<= 8;
enc |= b;
g_idx += 1;
}
for _ in 0..4 {
out.push(char::from_u32(CRYPT_HASH64[(enc & 0x3F) as usize] as u32).unwrap());
enc >>= 6;
}
}
out
}
pub fn md5_sha2_hash64_encode(bs: &[u8]) -> String {
let ngroups = (bs.len() + 2) / 3;
let mut out = String::with_capacity(ngroups * 4);
for g in 0..ngroups {
let mut g_idx = g * 3;
let mut enc = 0u32;
for _ in 0..3 {
let b = (if g_idx < bs.len() { bs[g_idx] } else { 0 }) as u32;
enc >>= 8;
enc |= b << 16;
g_idx += 1;
}
for _ in 0..4 {
out.push(char::from_u32(CRYPT_HASH64[(enc & 0x3F) as usize] as u32).unwrap());
enc >>= 6;
}
}
match bs.len() % 3 {
1 => { out.pop(); out.pop(); },
2 => { out.pop(); },
_ => (),
}
out
}
pub fn decode_val(val: &str, len: usize) -> Result<u32> {
let mut processed = 0;
let mut s = 0u32;
for b in val.chars() {
let b = b as u32 - 0x20;
if b > 0x60 {
return Err(Error::EncodingError);
}
let dec = CRYPT_HASH64_ENC_MAP[b as usize];
if dec == 64 {
return Err(Error::EncodingError);
}
s >>= 6;
s |= (dec as u32) << 26;
processed += 1;
if processed == len {
break;
}
}
if processed < len {
return Err(Error::InsufficientLength);
}
Ok(s >> (32 - 6 * len))
}
pub fn encode_val(mut val: u32, mut nhex: usize) -> String {
let mut val_arr = [0u8; 4];
if nhex > 4 {
nhex = 4;
}
let vlen = nhex;
let mut i = 0;
while nhex > 0 {
nhex -= 1;
val_arr[i] = CRYPT_HASH64[(val & 0x3F) as usize];
val >>= 6;
i += 1;
}
from_utf8(&val_arr[..vlen]).unwrap().to_owned()
}