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
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
//! Functionality for encoding the outer document of an onion service descriptor.
//!
//! NOTE: `HsDescOuter` is a private helper for building hidden service descriptors, and is
//! not meant to be used directly. Hidden services will use `HsDescBuilder` to build and encode
//! hidden service descriptors.
use crate::doc::hsdesc::outer::{HS_DESC_SIGNATURE_PREFIX, HS_DESC_VERSION_CURRENT, HsOuterKwd};
use crate::encode::{NetdocBuilder, NetdocEncoder};
use rand::{CryptoRng, Rng};
use tor_bytes::EncodeError;
use tor_cert::EncodedEd25519Cert;
use tor_hscrypto::RevisionCounter;
use tor_llcrypto::pk::ed25519;
use tor_units::IntegerMinutes;
use base64ct::{Base64Unpadded, Encoding};
/// The representation of the outer wrapper of an onion service descriptor.
///
/// The format of this document is described in section 2.4. of rend-spec-v3.
#[derive(Debug)]
pub(super) struct HsDescOuter<'a> {
/// The short-term descriptor signing key.
pub(super) hs_desc_sign: &'a ed25519::Keypair,
/// The descriptor signing key certificate.
pub(super) hs_desc_sign_cert: EncodedEd25519Cert,
/// The lifetime of this descriptor, in minutes.
///
/// This doesn't actually list the starting time or the end time for the
/// descriptor: presumably, because we didn't want to leak the onion
/// service's view of the wallclock.
pub(super) lifetime: IntegerMinutes<u16>,
/// A revision counter to tell whether this descriptor is more or less recent
/// than another one for the same blinded ID.
pub(super) revision_counter: RevisionCounter,
/// The (superencrypted) middle document of the onion service descriptor.
///
/// The `superencrypted` field is created by encrypting an
/// [`build::middle::HsDescMiddle`](super::middle::HsDescMiddle)
/// middle document as described in
/// sections 2.5.1.1. and 2.5.1.2. of rend-spec-v3.
pub(super) superencrypted: Vec<u8>,
}
impl<'a> NetdocBuilder for HsDescOuter<'a> {
fn build_sign<R: Rng + CryptoRng>(self, _: &mut R) -> Result<String, EncodeError> {
use HsOuterKwd::*;
let HsDescOuter {
hs_desc_sign,
hs_desc_sign_cert,
lifetime,
revision_counter,
superencrypted,
} = self;
let mut encoder = NetdocEncoder::new();
let beginning = encoder.cursor();
encoder.item(HS_DESCRIPTOR).arg(&HS_DESC_VERSION_CURRENT);
encoder.item(DESCRIPTOR_LIFETIME).arg(&lifetime.to_string());
encoder
.item(DESCRIPTOR_SIGNING_KEY_CERT)
.object_bytes("ED25519 CERT", hs_desc_sign_cert.as_ref());
encoder.item(REVISION_COUNTER).arg(&*revision_counter);
encoder
.item(SUPERENCRYPTED)
.object_bytes("MESSAGE", superencrypted);
let end = encoder.cursor();
let mut text = HS_DESC_SIGNATURE_PREFIX.to_vec();
text.extend_from_slice(encoder.slice(beginning, end)?.as_bytes());
let signature = hs_desc_sign.sign(&text);
// TODO SPEC encoding of this signature is completely unspecified (rend-spec-v3 2.4)
// TODO SPEC base64 is sometimes padded, sometimes unpadded, but NONE of the specs ever say!
encoder
.item(SIGNATURE)
.arg(&Base64Unpadded::encode_string(&signature.to_bytes()));
encoder.finish().map_err(|e| e.into())
}
}
#[cfg(test)]
mod test {
// @@ begin test lint list maintained by maint/add_warning @@
#![allow(clippy::bool_assert_comparison)]
#![allow(clippy::clone_on_copy)]
#![allow(clippy::dbg_macro)]
#![allow(clippy::mixed_attributes_style)]
#![allow(clippy::print_stderr)]
#![allow(clippy::print_stdout)]
#![allow(clippy::single_char_pattern)]
#![allow(clippy::unwrap_used)]
#![allow(clippy::unchecked_time_subtraction)]
#![allow(clippy::useless_vec)]
#![allow(clippy::needless_pass_by_value)]
#![allow(clippy::string_slice)] // See arti#2571
//! <!-- @@ end test lint list maintained by maint/add_warning @@ -->
use std::time::UNIX_EPOCH;
use crate::doc::hsdesc::create_desc_sign_key_cert;
use super::*;
use tor_basic_utils::test_rng::Config;
use tor_hscrypto::pk::HsIdKeypair;
use tor_hscrypto::time::TimePeriod;
use tor_llcrypto::pk::ed25519::ExpandedKeypair;
use tor_units::IntegerMinutes;
// Some dummy bytes, not actually encrypted.
const TEST_SUPERENCRYPTED_VALUE: &[u8] = &[1, 2, 3, 4];
#[test]
fn outer_hsdesc() {
let mut rng = Config::Deterministic.into_rng();
let hs_id = ed25519::Keypair::generate(&mut rng);
let hs_desc_sign = ed25519::Keypair::generate(&mut rng);
let period = TimePeriod::new(
humantime::parse_duration("24 hours").unwrap(),
humantime::parse_rfc3339("2023-02-09T12:00:00Z").unwrap(),
humantime::parse_duration("12 hours").unwrap(),
)
.unwrap();
let (_public, blinded_id, _) = HsIdKeypair::from(ExpandedKeypair::from(&hs_id))
.compute_blinded_key(period)
.unwrap();
let hs_desc_sign_cert =
create_desc_sign_key_cert(&hs_desc_sign.verifying_key(), &blinded_id, UNIX_EPOCH)
.unwrap();
let hs_desc = HsDescOuter {
hs_desc_sign: &hs_desc_sign,
hs_desc_sign_cert,
lifetime: IntegerMinutes::new(20),
revision_counter: 9001.into(),
superencrypted: TEST_SUPERENCRYPTED_VALUE.into(),
}
.build_sign(&mut Config::Deterministic.into_rng())
.unwrap();
assert_eq!(
hs_desc,
r#"hs-descriptor 3
descriptor-lifetime 20
descriptor-signing-key-cert
-----BEGIN ED25519 CERT-----
AQgAAAAAAZZVJwNlzVw1ZQGO7MTzC5MsySASd+fswAcjdTJJOifXAQAgBACI78JJ
/MuWPH0T5rQziVMJK/yETbYCVycypjsytCmeA4eiWhcVBG4r6AY/fXqHZnI3ApID
fsb92Bs45IrOrkQdATb5mk1dlFb0X6+0wIF0P0gCVuAEkGv1kvcR/zpvhww=
-----END ED25519 CERT-----
revision-counter 9001
superencrypted
-----BEGIN MESSAGE-----
AQIDBA==
-----END MESSAGE-----
signature g6wu776AYYD+BXPBocToRXPF9xob3TB34hkR1/h8tDBGjGMnBWZw03INbiX6Z8FaOXCulccQ309fYEO/BmwyDQ
"#
);
}
}
|
