1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
|
use log::{info};
use bch_bindgen::bcachefs::bch_sb_handle;
use clap::builder::PossibleValue;
use crate::c_str;
use anyhow::anyhow;
#[derive(Clone, Debug)]
pub enum KeyLocation {
None,
Fail,
Wait,
Ask,
}
impl std::str::FromStr for KeyLocation {
type Err = anyhow::Error;
fn from_str(s: &str) -> anyhow::Result<Self> {
match s {
""|"none" => Ok(KeyLocation::None),
"fail" => Ok(KeyLocation::Fail),
"wait" => Ok(KeyLocation::Wait),
"ask" => Ok(KeyLocation::Ask),
_ => Err(anyhow!("invalid password option")),
}
}
}
impl clap::ValueEnum for KeyLocation {
fn value_variants<'a>() -> &'a [Self] {
&[
KeyLocation::None,
KeyLocation::Fail,
KeyLocation::Wait,
KeyLocation::Ask,
]
}
fn to_possible_value(&self) -> Option<PossibleValue> {
Some(match self {
Self::None => PossibleValue::new("none").alias(""),
Self::Fail => PossibleValue::new("fail"),
Self::Wait => PossibleValue::new("wait"),
Self::Ask => PossibleValue::new("ask"),
})
}
}
fn check_for_key(key_name: &std::ffi::CStr) -> anyhow::Result<bool> {
use bch_bindgen::keyutils::{self, keyctl_search};
let key_name = key_name.to_bytes_with_nul().as_ptr() as *const _;
let key_type = c_str!("user");
let key_id = unsafe { keyctl_search(keyutils::KEY_SPEC_USER_KEYRING, key_type, key_name, 0) };
if key_id > 0 {
info!("Key has became available");
Ok(true)
} else {
match errno::errno().0 {
libc::ENOKEY | libc::EKEYREVOKED => Ok(false),
_ => Err(crate::ErrnoError(errno::errno()).into()),
}
}
}
fn wait_for_key(uuid: &uuid::Uuid) -> anyhow::Result<()> {
let key_name = std::ffi::CString::new(format!("bcachefs:{}", uuid)).unwrap();
loop {
if check_for_key(&key_name)? {
break Ok(());
}
std::thread::sleep(std::time::Duration::from_secs(1));
}
}
const BCH_KEY_MAGIC: &str = "bch**key";
fn ask_for_key(sb: &bch_sb_handle) -> anyhow::Result<()> {
use bch_bindgen::bcachefs::{self, bch2_chacha_encrypt_key, bch_encrypted_key, bch_key};
use byteorder::{LittleEndian, ReadBytesExt};
use std::os::raw::c_char;
let key_name = std::ffi::CString::new(format!("bcachefs:{}", sb.sb().uuid())).unwrap();
if check_for_key(&key_name)? {
return Ok(());
}
let bch_key_magic = BCH_KEY_MAGIC.as_bytes().read_u64::<LittleEndian>().unwrap();
let crypt = sb.sb().crypt().unwrap();
let pass = if atty::is(atty::Stream::Stdin) {
rpassword::read_password_from_tty(Some("Enter passphrase: "))?
} else {
let mut line = String::new();
std::io::stdin().read_line(&mut line)?;
line
};
let pass = std::ffi::CString::new(pass.trim_end())?; // bind to keep the CString alive
let mut output: bch_key = unsafe {
bcachefs::derive_passphrase(
crypt as *const _ as *mut _,
pass.as_c_str().to_bytes_with_nul().as_ptr() as *const _,
)
};
let mut key = crypt.key().clone();
let ret = unsafe {
bch2_chacha_encrypt_key(
&mut output as *mut _,
sb.sb().nonce(),
&mut key as *mut _ as *mut _,
std::mem::size_of::<bch_encrypted_key>() as usize,
)
};
if ret != 0 {
Err(anyhow!("chacha decryption failure"))
} else if key.magic != bch_key_magic {
Err(anyhow!("failed to verify the password"))
} else {
let key_type = c_str!("user");
let ret = unsafe {
bch_bindgen::keyutils::add_key(
key_type,
key_name.as_c_str().to_bytes_with_nul() as *const _ as *const c_char,
&output as *const _ as *const _,
std::mem::size_of::<bch_key>() as usize,
bch_bindgen::keyutils::KEY_SPEC_USER_KEYRING,
)
};
if ret == -1 {
Err(anyhow!("failed to add key to keyring: {}", errno::errno()))
} else {
Ok(())
}
}
}
pub fn prepare_key(sb: &bch_sb_handle, password: KeyLocation) -> anyhow::Result<()> {
info!("checking if key exists for filesystem {}", sb.sb().uuid());
match password {
KeyLocation::Fail => Err(anyhow!("no key available")),
KeyLocation::Wait => Ok(wait_for_key(&sb.sb().uuid())?),
KeyLocation::Ask => ask_for_key(sb),
_ => Err(anyhow!("no keyoption specified for locked filesystem")),
}
}
|
