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
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
//! Timestamp CMS envelope and scoped original `TSTInfo` inspection.
use super::{TokenInfo, record};
use crate::content_source::{ContentError, SourceMap};
use crate::{ContentInfo, Error, ErrorCode, Result, SignedData, oid};
use structured_asn1::memory::{OwnedVec, Work};
use structured_asn1::{Encoding, Parser, Reader};
/// Timestamp envelope; reading does not establish signature, trust or chronology.
///
/// The original signed message stays borrowed. `TSTInfo` is read through a scoped
/// callback so BER joins cannot produce dangling borrowed models or require a
/// self-referential owned container. Independently retained results are explicit.
#[derive(Debug)]
pub struct Token<'a> {
message: SignedData<'a>,
faults: OwnedVec<Error>,
}
/// Failure inside the explicitly identified carried-content source.
#[derive(Debug)]
pub enum InfoError<E> {
/// Located `TSTInfo` processing failure, using the supplied source coordinates.
Processing(Error),
/// The caller's unchanged error from its inspection/verification operation.
Callback(E),
}
impl<'a> Token<'a> {
/// Reads the complete timestamp CMS envelope using the original parser.
/// The attached `TSTInfo` bytes are inspected by [`Self::with_info`].
pub fn read(parser: &'a Parser, document: &'a [u8], base: u64) -> Result<Self> {
let mut root = parser
.read(document, base)
.map_err(|error| Error::encoding(error, "contentInfo"))?;
Self::read_from(&mut root)
}
/// Reads a complete token from its original scoped source reader.
///
/// Source encoding, offsets, inherited depth, parser session and current
/// operation ceilings are preserved. No replacement parser, retagging or
/// copy is performed. Trailing bytes in this source window are refused.
pub fn read_from(root: &mut Reader<'a>) -> Result<Self> {
let (envelope, parent) = ContentInfo::read(root)?;
parent
.execution()
.charge_work(envelope.kind().as_bytes().len() as u64)
.map_err(|reason| {
Error::resource(reason, "contentInfo.contentType", envelope.span().start)
})?;
if envelope.kind() != oid::SIGNED_DATA {
return Err(Error::schema(
ErrorCode::UnexpectedContentType,
"contentInfo.contentType",
envelope.span().start,
));
}
let message = SignedData::read_element(&parent, envelope.content())?;
Self::from_message(message, &parent)
}
/// Applies timestamp envelope rules to an already decoded signed message.
///
/// RFC3161 §2.4.2 requires attached `TSTInfo` and only the TSA signature.
/// Inspection recovery of equal parsed signers is explicitly nonconforming:
/// retain the first original encoding and one `ExtraSignature` fault. The
/// common narrow comparer ignores BER container spellings, preserves exact
/// signedAttrs and opaque field identity, and never rewrites signed bytes.
/// Conflicting signer values refuse; this is not a trust/provider selector.
/// <https://www.rfc-editor.org/rfc/rfc3161#section-2.4.2>
pub fn from_message(message: SignedData<'a>, parent: &Reader<'a>) -> Result<Self> {
let field = "signedData.signerInfos";
let first = message
.signers()
.first()
.ok_or_else(|| Error::schema(ErrorCode::SignerCount, field, message.span().start))?;
first.require_session(parent, field)?;
let execution = parent.execution();
let mut faults = execution.vector();
let mut duplicate = None;
for extra in &message.signers()[1..] {
execution
.charge_work(1)
.map_err(|reason| Error::resource(reason, field, extra.span().start))?;
if !first.same_value(extra, parent)? {
return Err(Error::schema(
ErrorCode::SignerCount,
field,
extra.span().start,
));
}
duplicate.get_or_insert(extra.span().start);
}
if let Some(at) = duplicate {
record(
&mut faults,
Error::schema(ErrorCode::ExtraSignature, field, at),
)?;
}
record_counters(first, parent, &mut faults)?;
let content = message.content();
execution
.charge_work(content.kind().as_bytes().len() as u64)
.map_err(|reason| {
Error::resource(
reason,
"signedData.encapContentInfo.eContentType",
content.span().start,
)
})?;
if content.kind() != oid::TST_INFO {
return Err(Error::schema(
ErrorCode::UnexpectedContentType,
"signedData.encapContentInfo.eContentType",
content.span().start,
));
}
if content.content().is_none() {
return Err(Error::schema(
ErrorCode::DetachedContent,
"signedData.encapContentInfo.eContent",
content.span().start,
));
}
Ok(Self {
message,
faults: faults.into_owned(),
})
}
/// Original signed message, including unmodified signed attribute ranges.
#[must_use]
pub fn message(&self) -> &SignedData<'a> {
&self.message
}
/// The first original TSA signer, after nonempty/unique-reading admission.
#[must_use]
pub fn signer(&self) -> &crate::signer::SignerInfo<'a> {
&self.message.signers()[0]
}
/// Additional envelope diagnostics, separate from CMS and `TSTInfo` faults.
#[must_use]
pub fn faults(&self) -> &[Error] {
&self.faults
}
/// Reads the complete attached `TSTInfo` in a callback with honest provenance.
///
/// Owned output/error types cannot borrow temporary joins. Located errors
/// use the provided map's coordinates; that map is retained with every inner
/// error. The caller chooses verification/trust/request context, and admits
/// explicit independent proof data before leaving the callback.
/// A uniquely readable first value followed by trailing carried bytes is
/// returned with a located `TrailingData` fault; those bytes are not repaired
/// or parsed as another token. Diagnostic retention can itself refuse
/// resources. Complete checking still rejects the nonconforming information.
#[expect(
clippy::result_large_err,
reason = "preserve both original cause and accounted source context without allocating an error envelope"
)]
pub fn with_info<R, E>(
&self,
parent: &Reader<'_>,
callback: impl for<'scope> FnOnce(
&TokenInfo<'scope>,
&Reader<'scope>,
&SourceMap,
) -> core::result::Result<R, E>,
) -> core::result::Result<R, ContentError<InfoError<E>>> {
self.inspect(parent, None, callback)
}
/// Inspects a token decoded inside another scoped content source.
///
/// The parent map is composed before inspection. Errors retain physical
/// range metadata independently of both joined buffers; the original
/// parser depth and operation budgets still govern the nested reader.
#[expect(
clippy::result_large_err,
reason = "retain original cause and accounted physical source context"
)]
pub fn with_info_mapped<R, E>(
&self,
parent: &Reader<'_>,
source: &SourceMap,
callback: impl for<'scope> FnOnce(
&TokenInfo<'scope>,
&Reader<'scope>,
&SourceMap,
) -> core::result::Result<R, E>,
) -> core::result::Result<R, ContentError<InfoError<E>>> {
self.inspect(parent, Some(source), callback)
}
#[expect(
clippy::result_large_err,
reason = "retain original cause and accounted physical source context"
)]
fn inspect<R, E>(
&self,
parent: &Reader<'_>,
source: Option<&SourceMap>,
callback: impl for<'scope> FnOnce(
&TokenInfo<'scope>,
&Reader<'scope>,
&SourceMap,
) -> core::result::Result<R, E>,
) -> core::result::Result<R, ContentError<InfoError<E>>> {
let Some(content) = self.message.content().content() else {
return Err(ContentError::Processing(Error::schema(
ErrorCode::DetachedContent,
"signedData.encapContentInfo.eContent",
self.message.content().span().start,
)));
};
let decode = |reader: &mut Reader<'_>, context: &SourceMap| {
let info = TokenInfo::read_carried(reader).map_err(InfoError::Processing)?;
callback(&info, reader, context).map_err(InfoError::Callback)
};
match source {
Some(source) => {
content.with_nested_reader_mapped(parent, source, Encoding::Ber, "tstInfo", decode)
}
None => content.with_nested_reader(parent, Encoding::Ber, "tstInfo", decode),
}
}
}
fn record_counters<W: Work>(
signer: &crate::signer::SignerInfo<'_>,
parent: &Reader<'_>,
faults: &mut OwnedVec<Error, W>,
) -> Result<()> {
// RFC3161 §2.4.2 forbids signatures other than the TSA's. This presence
// check is separate from the legal unsigned countersignature walker:
// known OID plus unreadable/empty values or signed placement still counts.
// https://www.rfc-editor.org/rfc/rfc3161#section-2.4.2
for (attributes, field) in [
(
signer.signed_attributes(),
"signerInfo.signedAttrs.countersignature",
),
(
signer.unsigned_attributes(),
"signerInfo.unsignedAttrs.countersignature",
),
] {
let Some(attributes) = attributes else {
continue;
};
for attribute in attributes.all_in(oid::COUNTERSIGNATURE, parent) {
let attribute = attribute?;
record(
faults,
Error::schema(ErrorCode::ExtraSignature, field, attribute.span().start),
)?;
}
}
Ok(())
}