ic_memory/
declaration.rs

1use crate::{
2    key::{StableKey, StableKeyError},
3    schema::{SchemaMetadata, SchemaMetadataError},
4    slot::{MemoryManagerSlot, MemoryManagerSlotError},
5    text::{DiagnosticTextError, validate_diagnostic_text},
6};
7use serde::{Deserialize, Serialize};
8use std::collections::BTreeSet;
9
10///
11/// AllocationDeclaration
12///
13/// Checked runtime claim that a stable key should own an allocation slot.
14///
15/// Declarations are supplied by the current binary before opening storage.
16/// Constructors validate the stable key, label and schema metadata and accept
17/// an already checked slot. A declaration becomes authoritative only after
18/// validation against the recovered ledger and commitment in a generation.
19///
20
21#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
22#[serde(deny_unknown_fields)]
23pub struct AllocationDeclaration {
24    /// Durable stable key.
25    pub(crate) stable_key: StableKey,
26    /// Claimed allocation slot.
27    pub(crate) slot: MemoryManagerSlot,
28    /// Optional diagnostic label.
29    #[serde(deserialize_with = "crate::cbor::deserialize_present_option")]
30    pub(crate) label: Option<String>,
31    /// Optional diagnostic schema metadata.
32    pub(crate) schema: SchemaMetadata,
33}
34
35impl AllocationDeclaration {
36    /// Build a declaration from raw parts after validating diagnostic metadata.
37    pub fn new(
38        stable_key: impl AsRef<str>,
39        slot: MemoryManagerSlot,
40        label: Option<String>,
41        schema: SchemaMetadata,
42    ) -> Result<Self, DeclarationSnapshotError> {
43        let stable_key = StableKey::parse(stable_key).map_err(DeclarationSnapshotError::Key)?;
44        validate_label(label.as_deref())?;
45        schema
46            .validate()
47            .map_err(DeclarationSnapshotError::SchemaMetadata)?;
48        Ok(Self {
49            stable_key,
50            slot,
51            label,
52            schema,
53        })
54    }
55
56    /// Build a `MemoryManager` declaration with a diagnostic label.
57    pub fn memory_manager(
58        stable_key: impl AsRef<str>,
59        id: u8,
60        label: impl Into<String>,
61    ) -> Result<Self, DeclarationSnapshotError> {
62        Self::memory_manager_with_schema(stable_key, id, label, SchemaMetadata::default())
63    }
64
65    /// Build an unlabeled `MemoryManager` declaration.
66    pub fn memory_manager_unlabeled(
67        stable_key: impl AsRef<str>,
68        id: u8,
69    ) -> Result<Self, DeclarationSnapshotError> {
70        Self::memory_manager_unlabeled_with_schema(stable_key, id, SchemaMetadata::default())
71    }
72
73    /// Build a `MemoryManager` declaration with a diagnostic label and schema metadata.
74    pub fn memory_manager_with_schema(
75        stable_key: impl AsRef<str>,
76        id: u8,
77        label: impl Into<String>,
78        schema: SchemaMetadata,
79    ) -> Result<Self, DeclarationSnapshotError> {
80        let slot =
81            MemoryManagerSlot::new(id).map_err(DeclarationSnapshotError::MemoryManagerSlot)?;
82        Self::new(stable_key, slot, Some(label.into()), schema)
83    }
84
85    /// Build an unlabeled `MemoryManager` declaration with schema metadata.
86    pub fn memory_manager_unlabeled_with_schema(
87        stable_key: impl AsRef<str>,
88        id: u8,
89        schema: SchemaMetadata,
90    ) -> Result<Self, DeclarationSnapshotError> {
91        let slot =
92            MemoryManagerSlot::new(id).map_err(DeclarationSnapshotError::MemoryManagerSlot)?;
93        Self::new(stable_key, slot, None, schema)
94    }
95
96    /// Return the durable stable key claimed by this declaration.
97    #[must_use]
98    pub const fn stable_key(&self) -> &StableKey {
99        &self.stable_key
100    }
101
102    /// Return the allocation slot claimed by this declaration.
103    #[must_use]
104    pub const fn slot(&self) -> &MemoryManagerSlot {
105        &self.slot
106    }
107
108    /// Return the optional diagnostic label.
109    #[must_use]
110    pub fn label(&self) -> Option<&str> {
111        self.label.as_deref()
112    }
113
114    /// Return the optional schema metadata.
115    #[must_use]
116    pub const fn schema(&self) -> &SchemaMetadata {
117        &self.schema
118    }
119
120    /// Validate constructor invariants after decode or manual assembly.
121    pub fn validate(&self) -> Result<(), DeclarationSnapshotError> {
122        self.stable_key
123            .validate()
124            .map_err(DeclarationSnapshotError::Key)?;
125        validate_label(self.label.as_deref())?;
126        self.schema
127            .validate()
128            .map_err(DeclarationSnapshotError::SchemaMetadata)
129    }
130}
131
132///
133/// DeclarationSnapshot
134///
135/// Immutable runtime declaration snapshot ready for policy and history validation.
136///
137/// A snapshot is duplicate-free, but it is still not permission to open storage.
138/// Integrations should call [`crate::validate_allocations`], commit the staged
139/// generation, and only then expose committed allocation authority.
140///
141
142#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
143#[serde(deny_unknown_fields)]
144pub struct DeclarationSnapshot {
145    /// Runtime declarations.
146    declarations: Vec<AllocationDeclaration>,
147    /// Optional binary/runtime identity for generation diagnostics.
148    #[serde(deserialize_with = "crate::cbor::deserialize_present_option")]
149    runtime_fingerprint: Option<String>,
150}
151
152impl DeclarationSnapshot {
153    /// Create and validate a declaration snapshot.
154    pub fn new(declarations: Vec<AllocationDeclaration>) -> Result<Self, DeclarationSnapshotError> {
155        validate_declarations(&declarations)?;
156        reject_duplicates(&declarations)?;
157        Ok(Self {
158            declarations,
159            runtime_fingerprint: None,
160        })
161    }
162
163    /// Attach an optional runtime fingerprint.
164    pub fn with_runtime_fingerprint(
165        mut self,
166        fingerprint: impl Into<String>,
167    ) -> Result<Self, DeclarationSnapshotError> {
168        let fingerprint = fingerprint.into();
169        validate_runtime_fingerprint(Some(&fingerprint))?;
170        self.runtime_fingerprint = Some(fingerprint);
171        Ok(self)
172    }
173
174    /// Return true when the snapshot has no declarations.
175    #[must_use]
176    pub const fn is_empty(&self) -> bool {
177        self.declarations.is_empty()
178    }
179
180    /// Return the number of declarations in the snapshot.
181    #[must_use]
182    pub const fn len(&self) -> usize {
183        self.declarations.len()
184    }
185
186    /// Borrow the sealed declarations.
187    #[must_use]
188    pub fn declarations(&self) -> &[AllocationDeclaration] {
189        &self.declarations
190    }
191
192    /// Borrow the optional runtime fingerprint.
193    #[must_use]
194    pub fn runtime_fingerprint(&self) -> Option<&str> {
195        self.runtime_fingerprint.as_deref()
196    }
197
198    /// Validate decoded snapshot invariants before allocation validation.
199    pub fn validate(&self) -> Result<(), DeclarationSnapshotError> {
200        validate_declarations(&self.declarations)?;
201        reject_duplicates(&self.declarations)?;
202        validate_runtime_fingerprint(self.runtime_fingerprint.as_deref())
203    }
204
205    pub(crate) fn into_parts(self) -> (Vec<AllocationDeclaration>, Option<String>) {
206        (self.declarations, self.runtime_fingerprint)
207    }
208}
209
210///
211/// DeclarationSnapshotError
212///
213/// Declaration snapshot validation failure.
214#[non_exhaustive]
215#[derive(Clone, Debug, Eq, thiserror::Error, PartialEq)]
216pub enum DeclarationSnapshotError {
217    #[error("at most 255 allocation declarations are supported")]
218    TooManyDeclarations,
219    /// Stable-key grammar failure.
220    #[error(transparent)]
221    Key(StableKeyError),
222    /// `MemoryManager` slot validation failure.
223    #[error(transparent)]
224    MemoryManagerSlot(MemoryManagerSlotError),
225    /// Schema metadata encoding failure.
226    #[error(transparent)]
227    SchemaMetadata(SchemaMetadataError),
228    /// A stable key appeared more than once in one snapshot.
229    #[error("stable key '{0}' is declared more than once")]
230    DuplicateStableKey(StableKey),
231    /// An allocation slot appeared more than once in one snapshot.
232    #[error("allocation slot '{0:?}' is declared more than once")]
233    DuplicateSlot(MemoryManagerSlot),
234    /// Present declaration labels must be non-empty.
235    #[error("allocation declaration label must not be empty when present")]
236    EmptyLabel,
237    /// Declaration labels must stay bounded for durable ledger storage.
238    #[error("allocation declaration label must be at most 256 bytes")]
239    LabelTooLong,
240    /// Declaration labels must not require Unicode normalization.
241    #[error("allocation declaration label must be ASCII")]
242    NonAsciiLabel,
243    /// Declaration labels must be printable metadata.
244    #[error("allocation declaration label must not contain ASCII control characters")]
245    ControlCharacterLabel,
246    /// Present runtime fingerprints must be non-empty.
247    #[error("runtime_fingerprint must not be empty when present")]
248    EmptyRuntimeFingerprint,
249    /// Runtime fingerprints must stay bounded for durable ledger storage.
250    #[error("runtime_fingerprint must be at most 256 bytes")]
251    RuntimeFingerprintTooLong,
252    /// Runtime fingerprints must not require Unicode normalization.
253    #[error("runtime_fingerprint must be ASCII")]
254    NonAsciiRuntimeFingerprint,
255    /// Runtime fingerprints must be printable metadata.
256    #[error("runtime_fingerprint must not contain ASCII control characters")]
257    ControlCharacterRuntimeFingerprint,
258}
259
260fn validate_label(label: Option<&str>) -> Result<(), DeclarationSnapshotError> {
261    let Some(label) = label else {
262        return Ok(());
263    };
264    validate_diagnostic_text(label).map_err(|error| match error {
265        DiagnosticTextError::Empty => DeclarationSnapshotError::EmptyLabel,
266        DiagnosticTextError::TooLong => DeclarationSnapshotError::LabelTooLong,
267        DiagnosticTextError::NonAscii => DeclarationSnapshotError::NonAsciiLabel,
268        DiagnosticTextError::ControlCharacter => DeclarationSnapshotError::ControlCharacterLabel,
269    })
270}
271
272fn validate_declarations(
273    declarations: &[AllocationDeclaration],
274) -> Result<(), DeclarationSnapshotError> {
275    if declarations.len() > crate::constants::MAX_ALLOCATIONS {
276        return Err(DeclarationSnapshotError::TooManyDeclarations);
277    }
278    for declaration in declarations {
279        declaration.validate()?;
280    }
281    Ok(())
282}
283
284pub fn validate_runtime_fingerprint(
285    fingerprint: Option<&str>,
286) -> Result<(), DeclarationSnapshotError> {
287    let Some(fingerprint) = fingerprint else {
288        return Ok(());
289    };
290    validate_diagnostic_text(fingerprint).map_err(|error| match error {
291        DiagnosticTextError::Empty => DeclarationSnapshotError::EmptyRuntimeFingerprint,
292        DiagnosticTextError::TooLong => DeclarationSnapshotError::RuntimeFingerprintTooLong,
293        DiagnosticTextError::NonAscii => DeclarationSnapshotError::NonAsciiRuntimeFingerprint,
294        DiagnosticTextError::ControlCharacter => {
295            DeclarationSnapshotError::ControlCharacterRuntimeFingerprint
296        }
297    })
298}
299
300fn reject_duplicates(
301    declarations: &[AllocationDeclaration],
302) -> Result<(), DeclarationSnapshotError> {
303    let mut keys = BTreeSet::new();
304    let mut slots = [false; crate::constants::MAX_ALLOCATIONS];
305
306    for declaration in declarations {
307        let occupied = &mut slots[usize::from(declaration.slot.id())];
308        if *occupied {
309            return Err(DeclarationSnapshotError::DuplicateSlot(
310                declaration.slot.clone(),
311            ));
312        }
313        *occupied = true;
314        if !keys.insert(&declaration.stable_key) {
315            return Err(DeclarationSnapshotError::DuplicateStableKey(
316                declaration.stable_key.clone(),
317            ));
318        }
319    }
320
321    Ok(())
322}
323
324#[cfg(test)]
325mod tests {
326    use super::*;
327    use crate::slot::MemoryManagerSlot;
328
329    fn declaration(key: &str, id: u8) -> AllocationDeclaration {
330        AllocationDeclaration::new(
331            key,
332            MemoryManagerSlot::new(id).expect("usable slot"),
333            None,
334            SchemaMetadata::default(),
335        )
336        .expect("declaration")
337    }
338
339    #[test]
340    fn declaration_rejects_unbounded_label_metadata() {
341        let err = AllocationDeclaration::new(
342            "app.users.v1",
343            MemoryManagerSlot::new(100).expect("usable slot"),
344            Some("x".repeat(257)),
345            SchemaMetadata::default(),
346        )
347        .expect_err("label too long");
348
349        assert_eq!(err, DeclarationSnapshotError::LabelTooLong);
350    }
351
352    #[test]
353    fn memory_manager_declaration_constructor_builds_common_declaration() {
354        let declaration = AllocationDeclaration::memory_manager("app.orders.v1", 100, "orders")
355            .expect("declaration");
356
357        assert_eq!(declaration.stable_key.as_str(), "app.orders.v1");
358        assert_eq!(
359            declaration.slot,
360            MemoryManagerSlot::new(100).expect("usable slot")
361        );
362        assert_eq!(declaration.label.as_deref(), Some("orders"));
363        assert_eq!(declaration.schema, SchemaMetadata::default());
364    }
365
366    #[test]
367    fn memory_manager_declaration_constructor_rejects_invalid_slot() {
368        let err = AllocationDeclaration::memory_manager("app.orders.v1", u8::MAX, "orders")
369            .expect_err("sentinel must fail");
370
371        assert!(matches!(
372            err,
373            DeclarationSnapshotError::MemoryManagerSlot(_)
374        ));
375    }
376
377    #[test]
378    fn snapshot_decode_rejects_unusable_memory_manager_slot() {
379        let snapshot = DeclarationSnapshot::new(vec![declaration("app.orders.v1", 100)]).unwrap();
380        let mut value = serde_json::to_value(snapshot).unwrap();
381        value["declarations"][0]["slot"]["slot"]["MemoryManagerId"] = serde_json::json!(255);
382        assert!(serde_json::from_value::<DeclarationSnapshot>(value).is_err());
383    }
384
385    #[test]
386    fn snapshot_rejects_unbounded_runtime_fingerprint() {
387        let snapshot =
388            DeclarationSnapshot::new(vec![declaration("app.users.v1", 100)]).expect("snapshot");
389
390        let err = snapshot
391            .with_runtime_fingerprint("x".repeat(257))
392            .expect_err("fingerprint too long");
393
394        assert_eq!(err, DeclarationSnapshotError::RuntimeFingerprintTooLong);
395    }
396
397    #[test]
398    fn rejects_duplicate_keys() {
399        let err = DeclarationSnapshot::new(vec![
400            declaration("app.users.v1", 100),
401            declaration("app.users.v1", 101),
402        ])
403        .expect_err("duplicate key");
404
405        assert_eq!(
406            err,
407            DeclarationSnapshotError::DuplicateStableKey(StableKey::parse("app.users.v1").unwrap())
408        );
409    }
410
411    #[test]
412    fn rejects_duplicate_slots() {
413        for second_key in ["app.orders.v1", "app.users.v1"] {
414            let err = DeclarationSnapshot::new(vec![
415                declaration("app.users.v1", 100),
416                declaration(second_key, 100),
417            ])
418            .expect_err("duplicate slot precedes duplicate key");
419
420            assert_eq!(
421                err,
422                DeclarationSnapshotError::DuplicateSlot(MemoryManagerSlot::new(100).unwrap())
423            );
424        }
425    }
426}
ic_memory/declaration.rs

ic_memory/
declaration.rs
