OXYGENHUB
# 85ef828b6bf0 oxygen / crates / oxy-core / src / repo / sync.rs
61.9 KiB · Rust · last changed Delete bookmarks on a remote: oxy push REMOTE --delete NAME 1 month ago source blame history raw
1 
//! Serving and talking to remotes (spec §10.2, §16).
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3 
use super::*;
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/// What a push did, for hosts (hub spec §6.12).
6 
#[derive(Clone, Debug, Default)]
7 
pub struct PushReport {
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    pub results: Vec<RefResult>,
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    /// Accepted reference updates, in request order.
10 
    pub updated: Vec<RefUpdated>,
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    /// Changes this push stored that were not already present.
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    pub imported: Vec<ChangeHash>,
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}
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15 
#[derive(Clone, Debug)]
16 
pub struct RefUpdated {
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    pub name: String,
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    pub old_state: ObjectRef,
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    pub new_state: ObjectRef,
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    pub heads: Vec<ChangeHash>,
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}
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/// What a fetch brought in.
24 
#[derive(Debug, Clone, PartialEq, Eq, Default)]
25 
pub struct FetchReport {
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    /// Bookmark name, its heads, and how many changes were new.
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    pub refs: Vec<(String, Vec<ChangeHash>, usize)>,
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    /// Tags adopted from the remote.
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    pub new_tags: usize,
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    /// The remote has never presented a policy, so nothing was verified
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    /// against one (spec §14.5: warn loudly).
32 
    pub unverified: bool,
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}
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#[derive(Debug, Clone, PartialEq, Eq)]
36 
pub struct PullReport {
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    pub heads: Vec<ChangeHash>,
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    pub changed: bool,
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    pub checked_out: bool,
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}
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impl Repo {
43 
    // ------------------------------------------------------------ serving (spec §16)
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    fn ref_attest_path(&self, bookmark: &str) -> PathBuf {
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        self.oxy.join("attest").join(name_file(bookmark))
47 
    }
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    /// The latest reference attestation stored for a bookmark.
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    pub fn latest_ref_attest(&self, bookmark: &str) -> Result<Option<(ObjectRef, SignedAttest)>> {
51 
        match fs::read_to_string(self.ref_attest_path(bookmark)) {
52 
            Ok(h) => {
53 
                let r = ObjectRef::from_hex(h.trim())
54 
                    .ok_or_else(|| RepoError::Msg("corrupt attestation pointer".into()))?;
55 
                Ok(Some((
56 
                    r,
57 
                    SignedAttest {
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                        attest: self.store.get_attest(&r)?,
59 
                        sigs: self.store.signatures(&r)?,
60 
                    },
61 
                )))
62 
            }
63 
            Err(e) if e.kind() == std::io::ErrorKind::NotFound => Ok(None),
64 
            Err(e) => Err(e.into()),
65 
        }
66 
    }
67
68 
    fn set_ref_attest(&self, bookmark: &str, r: &ObjectRef) -> Result<()> {
69 
        fs::create_dir_all(self.oxy.join("attest"))?;
70 
        write_atomic(&self.ref_attest_path(bookmark), r.to_hex().as_bytes())
71 
    }
72
73 
    pub fn remote_refs(&self) -> Result<RefsResponse> {
74 
        let view = self.view()?;
75 
        let mut out = Vec::new();
76 
        for (name, state) in &view.bookmarks {
77 
            let latest = self.latest_ref_attest(name)?.map(|(_, a)| a);
78 
            let last_serial = latest.as_ref().and_then(|a| match a.attest.body {
79 
                AttestBody::Ref { serial, .. } => Some(serial),
80 
                _ => None,
81 
            });
82 
            let attestation = latest.filter(|a| matches!(&a.attest.body, AttestBody::Ref { new_state, .. } if new_state == state));
83 
            out.push(RemoteRef {
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                name: name.clone(),
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                state: *state,
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                heads: self.store.get_state(state)?.heads,
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                attestation,
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                last_serial,
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            });
90 
        }
91 
        let policy = self.current_policy()?.map(|(_, sp)| sp);
92 
        let history = self
93 
            .policy_history()?
94 
            .into_iter()
95 
            .filter(|sp| {
96 
                policy
97 
                    .as_ref()
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                    .is_some_and(|p| sp.policy.serial < p.policy.serial)
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            })
100 
            .collect();
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        Ok(RefsResponse {
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            refs: out,
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            policy,
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            tags: self.tag_refs()?,
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            history,
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        })
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    }
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    /// Every change reachable from `heads` that is in the store.
110 
    fn closure_in_store(&self, heads: &[ChangeHash]) -> Result<BTreeSet<ChangeHash>> {
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        let mut seen = BTreeSet::new();
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        let mut stack: Vec<ChangeHash> = heads.to_vec();
113 
        while let Some(h) = stack.pop() {
114 
            if seen.contains(&h) || !self.store.has(&h) {
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                continue;
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            }
117 
            seen.insert(h);
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            stack.extend(self.store.get_change(&h)?.deps);
119 
        }
120 
        Ok(seen)
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    }
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    /// The changes within `depth` dependency steps of `heads` (spec §17),
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    /// nearest first; depth 1 is the heads themselves.
125 
    pub fn shallow_changes(&self, heads: &[ChangeHash], depth: u32) -> Result<Vec<ChangeHash>> {
126 
        let mut out = Vec::new();
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        let mut seen: BTreeSet<ChangeHash> = BTreeSet::new();
128 
        let mut layer: Vec<ChangeHash> = heads.to_vec();
129 
        for _ in 0..depth.max(1) {
130 
            let mut next = Vec::new();
131 
            for h in layer {
132 
                if !seen.insert(h) || !self.store.has(&h) {
133 
                    continue;
134 
                }
135 
                let c = self.store.get_change(&h)?;
136 
                next.extend(c.deps.iter().copied());
137 
                out.push(h);
138 
            }
139 
            if next.is_empty() {
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                break;
141 
            }
142 
            layer = next;
143 
        }
144 
        out.reverse();
145 
        Ok(out)
146 
    }
147
148 
    fn shallow_path(&self) -> PathBuf {
149 
        self.oxy.join("shallow")
150 
    }
151
152 
    /// The shallow boundary: dependencies this repository does not hold (spec §17).
153 
    pub fn boundary(&self) -> BTreeSet<ChangeHash> {
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        fs::read_to_string(self.shallow_path())
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            .map(|t| t.lines().filter_map(ObjectRef::from_hex).collect())
156 
            .unwrap_or_default()
157 
    }
158
159 
    pub fn is_shallow(&self) -> bool {
160 
        !self.boundary().is_empty()
161 
    }
162
163 
    fn write_boundary(&self, boundary: &BTreeSet<ChangeHash>) -> Result<()> {
164 
        if boundary.is_empty() {
165 
            let _ = fs::remove_file(self.shallow_path());
166 
            return Ok(());
167 
        }
168 
        let text: String = boundary
169 
            .iter()
170 
            .map(|h| format!("{}\n", h.to_hex()))
171 
            .collect();
172 
        write_atomic(&self.shallow_path(), text.as_bytes())
173 
    }
174
175 
    /// Recompute the boundary from what is stored: every dependency of a
176 
    /// stored change that is not itself stored.
177 
    fn refresh_boundary(&self, imported: &[ChangeHash]) -> Result<()> {
178 
        let mut boundary = self.boundary();
179 
        boundary.retain(|h| !self.store.has(h));
180 
        for h in imported {
181 
            for d in self.store.get_change(h)?.deps {
182 
                if !self.store.has(&d) {
183 
                    boundary.insert(d);
184 
                }
185 
            }
186 
        }
187 
        self.write_boundary(&boundary)
188 
    }
189
190 
    /// Fetch `depth` more levels of history below the shallow boundary.
191 
    pub fn deepen(&self, remote_name: &str, depth: u32) -> Result<usize> {
192 
        let boundary = self.boundary();
193 
        if boundary.is_empty() {
194 
            return Ok(0);
195 
        }
196 
        let remote = self.open_named_remote(remote_name)?;
197 
        let wanted = remote.shallow(&boundary.iter().copied().collect::<Vec<_>>(), depth)?;
198 
        let bundle = remote.fetch(&wanted, self.config.max_blob)?;
199 
        let imported = self.import_bundle_shallow(&bundle, false)?;
200 
        if self.config.max_blob.is_some() {
201 
            self.register_missing_blobs(&imported, remote_name)?;
202 
        }
203 
        self.refresh_boundary(&imported)?;
204 
        Ok(imported.len())
205 
    }
206
207 
    /// `closure(want) \ closure(have)`, dependencies first (spec §16.2).
208 
    pub fn negotiate(&self, have: &[ChangeHash], want: &[ChangeHash]) -> Result<Vec<ChangeHash>> {
209 
        let have = self.closure_in_store(have)?;
210 
        // In a shallow repository the walk stops at the boundary, whose
211 
        // changes the remote is assumed to hold.
212 
        let boundary = self.boundary();
213 
        let mut out = Vec::new();
214 
        let mut done: BTreeSet<ChangeHash> = have.clone();
215 
        done.extend(boundary.iter().copied());
216 
        // Iterative post-order DFS.
217 
        let mut stack: Vec<(ChangeHash, bool)> = want.iter().rev().map(|h| (*h, false)).collect();
218 
        while let Some((h, expanded)) = stack.pop() {
219 
            if done.contains(&h) {
220 
                continue;
221 
            }
222 
            if !self.store.has(&h) {
223 
                return fail(format!("change {} is not in this repository", h.short(12)));
224 
            }
225 
            if expanded {
226 
                done.insert(h);
227 
                out.push(h);
228 
                continue;
229 
            }
230 
            stack.push((h, true));
231 
            for d in self.store.get_change(&h)?.deps {
232 
                if !done.contains(&d) {
233 
                    stack.push((d, false));
234 
                }
235 
            }
236 
        }
237 
        Ok(out)
238 
    }
239
240 
    /// Bundle changes (in the given dependency order) with their signatures,
241 
    /// seals, identities, blobs, chunks.
242 
    pub fn bundle_for(&self, changes: &[ChangeHash]) -> Result<Bundle> {
243 
        self.bundle_for_filtered(changes, None)
244 
    }
245
246 
    /// Objects by reference for the `objects` endpoint; a blob brings its chunks.
247 
    pub fn objects_for(&self, refs: &[ObjectRef]) -> Result<Vec<(ObjectType, Vec<u8>)>> {
248 
        let mut out = Vec::new();
249 
        for r in refs {
250 
            let (ty, body) = match self.store.get(r) {
251 
                Ok(x) => x,
252 
                Err(StoreError::NotFound(_)) => continue,
253 
                Err(e) => return Err(e.into()),
254 
            };
255 
            if ty == ObjectType::Blob {
256 
                for c in Blob::decode(&body)?.chunks {
257 
                    if let Ok((cty, cb)) = self.store.get(&c) {
258 
                        out.push((cty, cb));
259 
                    }
260 
                }
261 
            }
262 
            out.push((ty, body));
263 
        }
264 
        Ok(out)
265 
    }
266
267 
    /// Like `bundle_for`, leaving out blobs larger than `max_blob` bytes
268 
    /// (and their chunks) so the receiver fetches them lazily (spec §13.5).
269 
    pub fn bundle_for_filtered(
270 
        &self,
271 
        changes: &[ChangeHash],
272 
        max_blob: Option<u64>,
273 
    ) -> Result<Bundle> {
274 
        let mut bundle = Bundle::default();
275 
        let mut objects: BTreeSet<ObjectRef> = BTreeSet::new();
276 
        let mut seals: BTreeSet<ObjectRef> = BTreeSet::new();
277 
        let add_object = |r: &ObjectRef, objects: &mut BTreeSet<ObjectRef>| {
278 
            if !r.is_zero() && self.store.has(r) {
279 
                objects.insert(*r);
280 
            }
281 
        };
282 
        for h in changes {
283 
            let c = self.store.get_change(h)?;
284 
            let sigs = self.store.signatures(h)?;
285 
            add_object(&c.author, &mut objects);
286 
            for s in &sigs {
287 
                add_object(&s.key, &mut objects);
288 
            }
289 
            for e in &c.edits {
290 
                if let Edit::Replace { old, new, .. } = e {
291 
                    for b in [old, new].into_iter().flatten() {
292 
                        if self.store.has(b) {
293 
                            if let Ok(blob) =
294 
                                Blob::decode(&self.store.get_typed(b, ObjectType::Blob)?)
295 
                            {
296 
                                if max_blob.is_some_and(|m| blob.length > m) {
297 
                                    continue;
298 
                                }
299 
                                objects.insert(*b);
300 
                                objects.extend(blob.chunks.iter().copied());
301 
                            }
302 
                        }
303 
                    }
304 
                }
305 
            }
306 
            for s in self.store.seals_for(h)? {
307 
                seals.insert(s);
308 
            }
309 
            bundle.changes.push((c, sigs));
310 
        }
311 
        for r in seals {
312 
            let attest = self.store.get_attest(&r)?;
313 
            let sigs = self.store.signatures(&r)?;
314 
            for s in &sigs {
315 
                add_object(&s.key, &mut objects);
316 
            }
317 
            bundle.attests.push(SignedAttest { attest, sigs });
318 
        }
319 
        for r in objects {
320 
            let (ty, body) = self.store.get(&r)?;
321 
            bundle.objects.push((ty, body));
322 
        }
323 
        Ok(bundle)
324 
    }
325
326 
    /// Store a bundle's contents. With `strict`, every change must
327 
    /// authenticate (signature or seal by its author or a delegate).
328 
    pub fn import_bundle(&self, bundle: &Bundle, strict: bool) -> Result<Vec<ChangeHash>> {
329 
        self.import_bundle_inner(bundle, strict, false)
330 
    }
331
332 
    /// Like `import_bundle`, accepting changes whose dependencies are absent
333 
    /// (they join the shallow boundary).
334 
    pub fn import_bundle_shallow(&self, bundle: &Bundle, strict: bool) -> Result<Vec<ChangeHash>> {
335 
        self.import_bundle_inner(bundle, strict, true)
336 
    }
337
338 
    fn import_bundle_inner(
339 
        &self,
340 
        bundle: &Bundle,
341 
        strict: bool,
342 
        shallow: bool,
343 
    ) -> Result<Vec<ChangeHash>> {
344 
        let batch = self.store.begin_batch()?;
345 
        let result = self.import_bundle_batched(bundle, strict, shallow);
346 
        batch.finish()?;
347 
        result
348 
    }
349
350 
    fn import_bundle_batched(
351 
        &self,
352 
        bundle: &Bundle,
353 
        strict: bool,
354 
        shallow: bool,
355 
    ) -> Result<Vec<ChangeHash>> {
356 
        for (ty, body) in &bundle.objects {
357 
            match ty {
358 
                ObjectType::Chunk
359 
                | ObjectType::Blob
360 
                | ObjectType::Identity
361 
                | ObjectType::State
362 
                | ObjectType::Checkpoint => {
363 
                    self.store.put(*ty, body)?;
364 
                }
365 
                other => return fail(format!("bundle may not carry {} objects", other.name())),
366 
            }
367 
        }
368 
        for sa in &bundle.attests {
369 
            let r = self.store.put_attest(&sa.attest)?;
370 
            for sig in &sa.sigs {
371 
                self.store.put_signature(&r, sig)?;
372 
            }
373 
            if let AttestBody::Seal { hashes } = &sa.attest.body {
374 
                for h in hashes {
375 
                    self.store.index_seal(h, &r)?;
376 
                }
377 
            }
378 
        }
379 
        let incoming: BTreeSet<ChangeHash> = bundle.changes.iter().map(|(c, _)| c.hash()).collect();
380 
        let boundary = self.boundary();
381 
        let mut imported = Vec::new();
382 
        for (c, sigs) in &bundle.changes {
383 
            let h = c.hash();
384 
            for d in &c.deps {
385 
                if !self.store.has(d) && !incoming.contains(d) && !shallow && !boundary.contains(d)
386 
                {
387 
                    return fail(format!(
388 
                        "change {} depends on {}, which is neither stored nor in the bundle",
389 
                        h.short(12),
390 
                        d.short(12)
391 
                    ));
392 
                }
393 
            }
394 
            self.store.put_change(c)?;
395 
            for sig in sigs {
396 
                self.store.put_signature(&h, sig)?;
397 
            }
398 
            imported.push(h);
399 
        }
400 
        if strict {
401 
            for h in &imported {
402 
                if !matches!(self.authenticate_change(h)?, SignatureStatus::Valid { .. }) {
403 
                    return fail(format!(
404 
                        "change {} is not authenticated by its author",
405 
                        h.short(12)
406 
                    ));
407 
                }
408 
            }
409 
        }
410 
        Ok(imported)
411 
    }
412
413 
    /// Verify a reference attestation against an update it claims to describe.
414 
    /// `allow_equal` lets a client re-read the attestation it already has; a
415 
    /// server receiving a push requires a strictly greater serial.
416 
    /// A reference attestation signed by a delegate of an identity the
417 
    /// rule lists is authorized as that identity (spec §14.5): the identity
418 
    /// named the delegate, and the policy names the identity. Revoked keys
419 
    /// authorize nothing either way.
420 
    pub(crate) fn delegate_authorized(
421 
        &self,
422 
        p: &crate::policy::Policy,
423 
        signer: &KeyId,
424 
        reference: &str,
425 
    ) -> bool {
426 
        if p.is_revoked(signer) {
427 
            return false;
428 
        }
429 
        let Some(rule) = p.rule_for(reference) else {
430 
            return false;
431 
        };
432 
        rule.keys.iter().any(|k| {
433 
            !p.is_revoked(k)
434 
                && p.identity(k)
435 
                    .cloned()
436 
                    .or_else(|| self.store.get_identity(k).ok())
437 
                    .is_some_and(|id| id.delegates.contains(signer))
438 
        })
439 
    }
440
441 
    fn check_ref_attest(
442 
        &self,
443 
        sa: &SignedAttest,
444 
        name: &str,
445 
        old_state: &ObjectRef,
446 
        new_state: &ObjectRef,
447 
        last_serial: Option<u64>,
448 
        allow_equal: bool,
449 
    ) -> std::result::Result<u64, String> {
450 
        let AttestBody::Ref {
451 
            name: n,
452 
            old_state: o,
453 
            new_state: nw,
454 
            serial,
455 
        } = &sa.attest.body
456 
        else {
457 
            return Err("attestation is not a ref attestation".into());
458 
        };
459 
        if n != name || o != old_state || nw != new_state {
460 
            return Err("attestation does not describe this update".into());
461 
        }
462 
        if sa.attest.repo != self.id().map_err(|e| e.to_string())? {
463 
            return Err("attestation is for a different repository".into());
464 
        }
465 
        if let Some(last) = last_serial {
466 
            if *serial < last || (*serial == last && !allow_equal) {
467 
                return Err(format!(
468 
                    "attestation serial {serial} is not greater than the last seen {last}"
469 
                ));
470 
            }
471 
        }
472 
        let r = sa.attest.hash();
473 
        let sig = sa.sigs.first().ok_or("attestation carries no signature")?;
474 
        let id = self
475 
            .store
476 
            .get_identity(&sig.key)
477 
            .map_err(|_| format!("unknown key {}", sig.key.short(12)))?;
478 
        verify_signature(&id, sig, Domain::Attest, &r).map_err(|e| e.to_string())?;
479 
        Ok(*serial)
480 
    }
481
482 
    /// Accept a push (spec §16.4). Without a trust policy every repository
483 
    /// is unverified, so unsigned changes and unattested updates are accepted;
484 
    /// attestations that are present must still be valid. With a policy,
485 
    /// every change and update is checked against it. A newer policy in the
486 
    /// push is applied first when it is signed by the current roots.
487 
    pub fn receive_push(
488 
        &self,
489 
        bundle: Bundle,
490 
        updates: Vec<RefUpdate>,
491 
        policy: Option<SignedPolicy>,
492 
        tags: Vec<crate::protocol::TagRef>,
493 
    ) -> Result<Vec<RefResult>> {
494 
        Ok(self
495 
            .receive_push_report(bundle, updates, policy, tags)?
496 
            .results)
497 
    }
498
499 
    /// `receive_push` with what a host wants to log: each accepted
500 
    /// reference's old and new state and heads, and the changes this push
501 
    /// stored (hub spec §6.12).
502 
    pub fn receive_push_report(
503 
        &self,
504 
        bundle: Bundle,
505 
        updates: Vec<RefUpdate>,
506 
        policy: Option<SignedPolicy>,
507 
        tags: Vec<crate::protocol::TagRef>,
508 
    ) -> Result<PushReport> {
509 
        let mut report = PushReport::default();
510 
        let results = &mut report.results;
511 
        if let Some(sp) = policy {
512 
            match self.adopt_policy_chain(&bundle.policies, &sp, "push received") {
513 
                Ok(()) => {
514 
                    results.push(RefResult {
515 
                        name: "policy".into(),
516 
                        ok: true,
517 
                        reason: format!("serial {}", sp.policy.serial),
518 
                    });
519 
                }
520 
                Err(e) => {
521 
                    results.push(RefResult {
522 
                        name: "policy".into(),
523 
                        ok: false,
524 
                        reason: e,
525 
                    });
526 
                    for u in updates {
527 
                        results.push(RefResult {
528 
                            name: u.name,
529 
                            ok: false,
530 
                            reason: "policy update was rejected".into(),
531 
                        });
532 
                    }
533 
                    return Ok(report);
534 
                }
535 
            }
536 
        }
537 
        let policy = self.current_policy()?.map(|(_, sp)| sp.policy);
538 
        match self.import_bundle(&bundle, policy.is_some()) {
539 
            Ok(imported) => report.imported = imported,
540 
            Err(e) => {
541 
                for u in updates {
542 
                    results.push(RefResult {
543 
                        name: u.name,
544 
                        ok: false,
545 
                        reason: e.to_string(),
546 
                    });
547 
                }
548 
                return Ok(report);
549 
            }
550 
        }
551 
        let (op_ref, op) = self.head_op()?;
552 
        let mut view = op.view.clone();
553 
        let mut names = Vec::new();
554 
        for u in updates {
555 
            let outcome = self.apply_update(&mut view, &u, policy.as_ref());
556 
            let (ok, reason) = match outcome {
557 
                Ok(()) => (true, String::new()),
558 
                Err(e) => (false, e),
559 
            };
560 
            if ok {
561 
                names.push(u.name.clone());
562 
                let heads = self
563 
                    .store
564 
                    .get_state(&u.new_state)
565 
                    .map(|s| s.heads)
566 
                    .unwrap_or_default();
567 
                report.updated.push(RefUpdated {
568 
                    name: u.name.clone(),
569 
                    old_state: u.old_state,
570 
                    new_state: u.new_state,
571 
                    heads,
572 
                });
573 
            }
574 
            results.push(RefResult {
575 
                name: u.name,
576 
                ok,
577 
                reason,
578 
            });
579 
        }
580 
        for t in &tags {
581 
            let name = format!("tags/{}", t.name);
582 
            match self.adopt_tag(&mut view, t, policy.as_ref()) {
583 
                Ok(()) => {
584 
                    names.push(name.clone());
585 
                    results.push(RefResult {
586 
                        name,
587 
                        ok: true,
588 
                        reason: String::new(),
589 
                    });
590 
                }
591 
                Err(e) => results.push(RefResult {
592 
                    name,
593 
                    ok: false,
594 
                    reason: e,
595 
                }),
596 
            }
597 
        }
598 
        if !names.is_empty() {
599 
            self.record_op(
600 
                &[op_ref],
601 
                &format!("push received: {}", names.join(" ")),
602 
                view,
603 
            )?;
604 
        }
605 
        Ok(report)
606 
    }
607
608 
    /// A deletion (spec §16.4): `new_state` is zero. The bookmark must exist
609 
    /// at `old_state`, is never the repository's own bookmark (its default),
610 
    /// and under a policy needs an attestation by a key that may update it.
611 
    /// The deletion's attestation stays the bookmark's latest, so an older
612 
    /// one cannot be replayed to bring it back.
613 
    fn apply_deletion(
614 
        &self,
615 
        view: &mut View,
616 
        u: &RefUpdate,
617 
        policy: Option<&crate::policy::Policy>,
618 
    ) -> std::result::Result<(), String> {
619 
        let Some(current) = view.bookmarks.get(&u.name).copied() else {
620 
            return Err(format!("no bookmark {:?} to delete", u.name));
621 
        };
622 
        if current != u.old_state {
623 
            return Err("stale: the remote bookmark has moved; pull first".into());
624 
        }
625 
        if u.name == self.config.bookmark {
626 
            return Err(format!(
627 
                "{:?} is this repository's default bookmark and cannot be deleted",
628 
                u.name
629 
            ));
630 
        }
631 
        if let Some(p) = policy {
632 
            let Some(sa) = &u.attestation else {
633 
                return Err(format!(
634 
                    "deleting {:?} requires a signed reference attestation under this repository's policy",
635 
                    u.name
636 
                ));
637 
            };
638 
            let signer = sa
639 
                .sigs
640 
                .first()
641 
                .map(|s| s.key)
642 
                .ok_or("attestation carries no signature")?;
643 
            if !p.authorizes(&signer, &u.name) && !self.delegate_authorized(p, &signer, &u.name) {
644 
                return Err(format!(
645 
                    "key {} may not delete {:?} under this repository's policy",
646 
                    signer.short(12),
647 
                    u.name
648 
                ));
649 
            }
650 
        }
651 
        if let Some(sa) = &u.attestation {
652 
            let last = self
653 
                .latest_ref_attest(&u.name)
654 
                .map_err(|e| e.to_string())?
655 
                .and_then(|(_, a)| match a.attest.body {
656 
                    AttestBody::Ref { serial, .. } => Some(serial),
657 
                    _ => None,
658 
                });
659 
            self.check_ref_attest(sa, &u.name, &u.old_state, &u.new_state, last, false)?;
660 
            let r = self
661 
                .store
662 
                .put_attest(&sa.attest)
663 
                .map_err(|e| e.to_string())?;
664 
            for sig in &sa.sigs {
665 
                self.store
666 
                    .put_signature(&r, sig)
667 
                    .map_err(|e| e.to_string())?;
668 
            }
669 
            self.set_ref_attest(&u.name, &r)
670 
                .map_err(|e| e.to_string())?;
671 
        }
672 
        view.bookmarks.remove(&u.name);
673 
        Ok(())
674 
    }
675
676 
    fn apply_update(
677 
        &self,
678 
        view: &mut View,
679 
        u: &RefUpdate,
680 
        policy: Option<&crate::policy::Policy>,
681 
    ) -> std::result::Result<(), String> {
682 
        if u.name == "policy" {
683 
            return Err(
684 
                "the policy reference is updated by sending a policy, not a bookmark update".into(),
685 
            );
686 
        }
687 
        let empty = self
688 
            .store
689 
            .put_state(&StateObject::new(vec![]))
690 
            .map_err(|e| e.to_string())?;
691 
        if u.new_state.is_zero() {
692 
            return self.apply_deletion(view, u, policy);
693 
        }
694 
        let current = view.bookmarks.get(&u.name).copied().unwrap_or(empty);
695 
        if current != u.old_state {
696 
            return Err("stale: the remote bookmark has moved; pull first".into());
697 
        }
698 
        let new_state = self
699 
            .store
700 
            .get_state(&u.new_state)
701 
            .map_err(|_| "new state object is missing".to_string())?;
702 
        for h in &new_state.heads {
703 
            if !self.store.has(h) {
704 
                return Err(format!("head {} is missing", h.short(12)));
705 
            }
706 
        }
707 
        if !u.force {
708 
            let old_heads = self
709 
                .store
710 
                .get_state(&current)
711 
                .map_err(|e| e.to_string())?
712 
                .heads;
713 
            let closure = self
714 
                .closure_in_store(&new_state.heads)
715 
                .map_err(|e| e.to_string())?;
716 
            if let Some(h) = old_heads.iter().find(|h| !closure.contains(h)) {
717 
                return Err(format!(
718 
                    "not a fast-forward: current head {} would be dropped (use --force)",
719 
                    h.short(12)
720 
                ));
721 
            }
722 
        }
723 
        if let Some(p) = policy {
724 
            let Some(sa) = &u.attestation else {
725 
                return Err(format!(
726 
                    "{:?} requires a signed reference attestation under this repository's policy",
727 
                    u.name
728 
                ));
729 
            };
730 
            let signer = sa
731 
                .sigs
732 
                .first()
733 
                .map(|s| s.key)
734 
                .ok_or("attestation carries no signature")?;
735 
            if !p.authorizes(&signer, &u.name) && !self.delegate_authorized(p, &signer, &u.name) {
736 
                return Err(format!(
737 
                    "key {} may not update {:?} under this repository's policy",
738 
                    signer.short(12),
739 
                    u.name
740 
                ));
741 
            }
742 
            let old_heads = self
743 
                .store
744 
                .get_state(&current)
745 
                .map_err(|e| e.to_string())?
746 
                .heads;
747 
            self.state_allowed(&old_heads, &new_state.heads, p, &u.name)?;
748 
        }
749 
        if let Some(sa) = &u.attestation {
750 
            let last = self
751 
                .latest_ref_attest(&u.name)
752 
                .map_err(|e| e.to_string())?
753 
                .and_then(|(_, a)| match a.attest.body {
754 
                    AttestBody::Ref { serial, .. } => Some(serial),
755 
                    _ => None,
756 
                });
757 
            self.check_ref_attest(sa, &u.name, &u.old_state, &u.new_state, last, false)?;
758 
            let r = self
759 
                .store
760 
                .put_attest(&sa.attest)
761 
                .map_err(|e| e.to_string())?;
762 
            for sig in &sa.sigs {
763 
                self.store
764 
                    .put_signature(&r, sig)
765 
                    .map_err(|e| e.to_string())?;
766 
            }
767 
            self.set_ref_attest(&u.name, &r)
768 
                .map_err(|e| e.to_string())?;
769 
        }
770 
        view.bookmarks.insert(u.name.clone(), u.new_state);
771 
        Ok(())
772 
    }
773
774 
    // ------------------------------------------------------------ client side
775
776 
    fn remote_url(&self, name: &str) -> Result<String> {
777 
        self.config.remotes.get(name).cloned().ok_or_else(|| {
778 
            RepoError::Msg(format!(
779 
                "no remote named {name:?}; add one with `oxy remote add`"
780 
            ))
781 
        })
782 
    }
783
784 
    /// Credentials and trust for a remote: `remote.<name>.token` (else
785 
    /// `$OXY_TOKEN`) and `remote.<name>.ca` (else `$OXY_CA`).
786 
    /// Refuse a remote that is another repository. An **unbound** remote
787 
    /// (id all zero: a hosted repository nobody has pushed to) is accepted
788 
    /// for pushes, which bind it to this repository's id (spec §16.1).
789 
    fn check_remote_id(
790 
        &self,
791 
        remote: &dyn crate::protocol::Remote,
792 
        remote_name: &str,
793 
        allow_unbound: bool,
794 
    ) -> Result<()> {
795 
        let theirs = remote.repo_id()?;
796 
        if theirs == self.id()? {
797 
            return Ok(());
798 
        }
799 
        if theirs == crate::protocol::UNBOUND_ID {
800 
            if allow_unbound {
801 
                return Ok(());
802 
            }
803 
            return fail(format!(
804 
                "remote {remote_name:?} is empty and unbound: push to it first"
805 
            ));
806 
        }
807 
        fail(format!(
808 
            "remote {remote_name:?} is a different repository (repository IDs differ); check its URL with `oxy remote list`"
809 
        ))
810 
    }
811
812 
    pub(crate) fn remote_options(&self, name: &str) -> RemoteOptions {
813 
        RemoteOptions {
814 
            repo_id: self.id().ok(),
815 
            token: self
816 
                .config
817 
                .remote_tokens
818 
                .get(name)
819 
                .cloned()
820 
                .or_else(|| std::env::var("OXY_TOKEN").ok()),
821 
            ca: self
822 
                .config
823 
                .remote_cas
824 
                .get(name)
825 
                .map(PathBuf::from)
826 
                .or_else(|| std::env::var("OXY_CA").ok().map(PathBuf::from)),
827 
        }
828 
    }
829
830 
    /// Push seal attestations on their own (hub spec §7.4): a bundle with
831 
    /// no changes and no reference updates, which the receiver stores.
832 
    pub fn push_seals(&self, remote_name: &str, seals: &[ObjectRef]) -> Result<()> {
833 
        let remote = self.open_named_remote(remote_name)?;
834 
        self.check_remote_id(remote.as_ref(), remote_name, false)?;
835 
        let mut bundle = Bundle::default();
836 
        for r in seals {
837 
            let attest = self.store.get_attest(r)?;
838 
            let sigs = self.store.signatures(r)?;
839 
            bundle
840 
                .attests
841 
                .push(crate::protocol::SignedAttest { attest, sigs });
842 
        }
843 
        let results = remote.push(bundle, vec![], None, vec![])?;
844 
        if let Some(r) = results.iter().find(|r| !r.ok) {
845 
            return fail(format!("{}: {}", r.name, r.reason));
846 
        }
847 
        Ok(())
848 
    }
849
850 
    /// The remote whose URL starts with `base` (a hub), if configured.
851 
    pub fn remote_for_url(&self, base: &str) -> Option<String> {
852 
        let base = base.trim_end_matches('/');
853 
        self.config
854 
            .remotes
855 
            .iter()
856 
            .find(|(_, url)| url.trim_end_matches('/') == base)
857 
            .map(|(name, _)| name.clone())
858 
    }
859
860 
    /// Open a remote by name or, failing that, by URL with the default
861 
    /// credentials (`OXY_TOKEN`, `OXY_CA`).
862 
    pub fn open_remote_at(&self, url: &str) -> Result<(String, Box<dyn crate::protocol::Remote>)> {
863 
        if let Some(name) = self.remote_for_url(url) {
864 
            return Ok((name.clone(), self.open_named_remote(&name)?));
865 
        }
866 
        let options = RemoteOptions {
867 
            token: std::env::var("OXY_TOKEN").ok(),
868 
            ca: std::env::var("OXY_CA").ok().map(PathBuf::from),
869 
            repo_id: self.id().ok(),
870 
        };
871 
        Ok((url.to_string(), open_remote(url, &options)?))
872 
    }
873
874 
    /// Credentials for a URL: those of the configured remote with that
875 
    /// URL, else the environment's.
876 
    pub fn options_for_url(&self, url: &str) -> RemoteOptions {
877 
        match self.remote_for_url(url) {
878 
            Some(name) => self.remote_options(&name),
879 
            None => RemoteOptions {
880 
                token: std::env::var("OXY_TOKEN").ok(),
881 
                ca: std::env::var("OXY_CA").ok().map(PathBuf::from),
882 
                repo_id: self.id().ok(),
883 
            },
884 
        }
885 
    }
886
887 
    fn open_named_remote(&self, name: &str) -> Result<Box<dyn crate::protocol::Remote>> {
888 
        open_remote(&self.remote_url(name)?, &self.remote_options(name))
889 
    }
890
891 
    fn serial_path(&self, remote: &str, bookmark: &str) -> PathBuf {
892 
        self.oxy
893 
            .join("remotes")
894 
            .join(remote)
895 
            .join(format!("{bookmark}.serial"))
896 
    }
897
898 
    fn last_seen_serial(&self, remote: &str, bookmark: &str) -> Option<u64> {
899 
        fs::read_to_string(self.serial_path(remote, bookmark))
900 
            .ok()
901 
            .and_then(|s| s.trim().parse().ok())
902 
    }
903
904 
    fn record_serial(&self, remote: &str, bookmark: &str, serial: u64) -> Result<()> {
905 
        let p = self.serial_path(remote, bookmark);
906 
        fs::create_dir_all(p.parent().unwrap())?;
907 
        write_atomic(&p, serial.to_string().as_bytes())
908 
    }
909
910 
    fn policy_serial_path(&self, remote: &str) -> PathBuf {
911 
        self.oxy.join("remotes").join(remote).join("policy.serial")
912 
    }
913
914 
    /// The highest policy serial `remote` has ever presented.
915 
    fn remote_policy_serial(&self, remote: &str) -> Option<u64> {
916 
        fs::read_to_string(self.policy_serial_path(remote))
917 
            .ok()
918 
            .and_then(|s| s.trim().parse().ok())
919 
    }
920
921 
    fn record_policy_serial(&self, remote: &str, serial: u64) -> Result<()> {
922 
        let p = self.policy_serial_path(remote);
923 
        fs::create_dir_all(p.parent().unwrap())?;
924 
        write_atomic(&p, serial.to_string().as_bytes())
925 
    }
926
927 
    fn lazy_dir(&self) -> PathBuf {
928 
        self.oxy.join("lazy")
929 
    }
930
931 
    /// Remember that `blob` was withheld by `remote` (spec §13.5).
932 
    fn register_lazy(&self, blob: &ObjectRef, remote: &str) -> Result<()> {
933 
        fs::create_dir_all(self.lazy_dir())?;
934 
        write_atomic(&self.lazy_dir().join(blob.to_hex()), remote.as_bytes())
935 
    }
936
937 
    /// Which remote promised an absent blob, if any.
938 
    pub fn lazy_remote(&self, blob: &ObjectRef) -> Option<String> {
939 
        fs::read_to_string(self.lazy_dir().join(blob.to_hex()))
940 
            .ok()
941 
            .map(|s| s.trim().to_string())
942 
    }
943
944 
    /// Fetch an absent blob (and its chunks) from the remote that promised it.
945 
    pub(crate) fn fetch_lazy_blob(&self, blob: &ObjectRef) -> Result<()> {
946 
        let Some(remote_name) = self.lazy_remote(blob) else {
947 
            return Err(RepoError::Store(StoreError::NotFound(*blob)));
948 
        };
949 
        let remote = self.open_named_remote(&remote_name)?;
950 
        let objects = remote.objects(&[*blob])?;
951 
        for (ty, body) in objects {
952 
            if matches!(ty, ObjectType::Blob | ObjectType::Chunk) {
953 
                self.store.put(ty, &body)?;
954 
            }
955 
        }
956 
        if !self.store.has(blob) {
957 
            return fail(format!(
958 
                "{remote_name} did not send blob {}",
959 
                blob.short(12)
960 
            ));
961 
        }
962 
        let _ = fs::remove_file(self.lazy_dir().join(blob.to_hex()));
963 
        Ok(())
964 
    }
965
966 
    /// After importing from `remote`, record every blob the changes reference
967 
    /// that the store lacks as lazily available from that remote.
968 
    fn register_missing_blobs(&self, changes: &[ChangeHash], remote: &str) -> Result<usize> {
969 
        let mut n = 0;
970 
        for h in changes {
971 
            let c = self.store.get_change(h)?;
972 
            for e in &c.edits {
973 
                if let Edit::Replace { old, new, .. } = e {
974 
                    for b in [old, new].into_iter().flatten() {
975 
                        if !self.store.has(b) {
976 
                            self.register_lazy(b, remote)?;
977 
                            n += 1;
978 
                        }
979 
                    }
980 
                }
981 
            }
982 
        }
983 
        Ok(n)
984 
    }
985
986 
    /// Every head this repository knows: bookmarks, remote tracking, working copy.
987 
    pub fn known_heads(&self, view: &View) -> Result<Vec<ChangeHash>> {
988 
        let mut have: BTreeSet<ChangeHash> = BTreeSet::new();
989 
        for st in view
990 
            .bookmarks
991 
            .values()
992 
            .chain(view.remotes.values().flat_map(|b| b.values()))
993 
        {
994 
            if let Ok(s) = self.store.get_state(st) {
995 
                have.extend(s.heads);
996 
            }
997 
        }
998 
        have.extend(view.workspaces.values().copied());
999 
        Ok(have.into_iter().collect())
1000 
    }
1001
1002 
    /// Fetch every bookmark of a remote into `remotes/<name>/bookmarks/*` (spec §10.2).
1003 
    pub fn fetch(&self, remote_name: &str) -> Result<FetchReport> {
1004 
        let remote = self.open_named_remote(remote_name)?;
1005 
        self.check_remote_id(remote.as_ref(), remote_name, false)?;
1006 
        let resp = remote.refs()?;
1007 
        // Trust policy (spec §14.5). Adopt the remote's policy when it is newer
1008 
        // and signed by roots we trust, or on first contact. A remote that
1009 
        // once presented a policy may never present none or an older one:
1010 
        // that is a downgrade. A remote that never presented one is
1011 
        // unverified, and this fetch is checked only as far as possible.
1012 
        let local_policy = self.current_policy()?.map(|(_, sp)| sp.policy);
1013 
        let seen = self.remote_policy_serial(remote_name);
1014 
        let mut unverified = false;
1015 
        match &resp.policy {
1016 
            Some(sp) => {
1017 
                if seen.is_some_and(|s| sp.policy.serial < s) {
1018 
                    return fail(format!("{remote_name} presents policy serial {} but presented {} before: refusing the downgrade", sp.policy.serial, seen.unwrap()));
1019 
                }
1020 
                match &local_policy {
1021 
                    Some(l) if sp.policy.serial < l.serial => {}
1022 
                    Some(l) if sp.policy.serial == l.serial => {
1023 
                        if sp.policy.hash() != l.hash() {
1024 
                            return fail(format!(
1025 
                                "{remote_name} presents a different policy with the same serial {}",
1026 
                                l.serial
1027 
                            ));
1028 
                        }
1029 
                    }
1030 
                    _ => {
1031 
                        self.adopt_policy_chain(
1032 
                            &resp.history,
1033 
                            sp,
1034 
                            &format!("oxy fetch {remote_name}"),
1035 
                        )
1036 
                        .map_err(|e| RepoError::Msg(format!("policy from {remote_name}: {e}")))?;
1037 
                    }
1038 
                }
1039 
                self.record_policy_serial(remote_name, sp.policy.serial)?;
1040 
            }
1041 
            None => {
1042 
                if seen.is_some() {
1043 
                    return fail(format!("{remote_name} presented a policy before but has none now: refusing the downgrade"));
1044 
                }
1045 
                unverified = true;
1046 
            }
1047 
        }
1048 
        let policy = if unverified {
1049 
            None
1050 
        } else {
1051 
            self.current_policy()?.map(|(_, sp)| sp.policy)
1052 
        };
1053 
        let (op_ref, op) = self.head_op()?;
1054 
        let mut view = op.view.clone();
1055 
        let have = self.known_heads(&view)?;
1056 
        let mut report = Vec::new();
1057 
        let max_blob = self.config.max_blob;
1058 
        for r in resp.refs {
1059 
            let needed = remote.negotiate(&have, &r.heads)?;
1060 
            let bundle = remote.fetch(&needed, max_blob)?;
1061 
            // Changes are not individually re-verified here: the bookmark's
1062 
            // attestation (checked below) binds its whole state, and the
1063 
            // receiver of the push verified the added changes at that time.
1064 
            let imported = self.import_bundle(&bundle, false)?;
1065 
            if max_blob.is_some() {
1066 
                self.register_missing_blobs(&imported, remote_name)?;
1067 
            }
1068 
            for h in &r.heads {
1069 
                if !self.store.has(h) {
1070 
                    return fail(format!("remote did not send head {}", h.short(12)));
1071 
                }
1072 
            }
1073 
            let state = self.store.put_state(&StateObject::new(r.heads.clone()))?;
1074 
            if state != r.state {
1075 
                return fail(format!(
1076 
                    "remote state {} does not match its heads",
1077 
                    r.state.short(12)
1078 
                ));
1079 
            }
1080 
            if let Some(p) = &policy {
1081 
                let Some(sa) = &r.attestation else {
1082 
                    return fail(format!(
1083 
                        "{remote_name}/{} has no attestation, which its policy requires",
1084 
                        r.name
1085 
                    ));
1086 
                };
1087 
                let signer = sa
1088 
                    .sigs
1089 
                    .first()
1090 
                    .map(|s| s.key)
1091 
                    .ok_or_else(|| RepoError::Msg("attestation carries no signature".into()))?;
1092 
                if !p.authorizes(&signer, &r.name) && !self.delegate_authorized(p, &signer, &r.name) {
1093 
                    return fail(format!(
1094 
                        "{remote_name}/{}: attested by {}, which the policy does not authorize for this bookmark; a policy owner can grant it with `oxy policy grant`",
1095 
                        r.name,
1096 
                        signer.short(12)
1097 
                    ));
1098 
                }
1099 
            }
1100 
            if let Some(sa) = &r.attestation {
1101 
                let AttestBody::Ref {
1102 
                    old_state,
1103 
                    new_state,
1104 
                    ..
1105 
                } = &sa.attest.body
1106 
                else {
1107 
                    return fail("remote sent a non-ref attestation for a bookmark");
1108 
                };
1109 
                let (old_state, new_state) = (*old_state, *new_state);
1110 
                let serial = self
1111 
                    .check_ref_attest(
1112 
                        sa,
1113 
                        &r.name,
1114 
                        &old_state,
1115 
                        &new_state,
1116 
                        self.last_seen_serial(remote_name, &r.name),
1117 
                        true,
1118 
                    )
1119 
                    .map_err(|e| {
1120 
                        RepoError::Msg(format!("attestation for {}/{}: {e}", remote_name, r.name))
1121 
                    })?;
1122 
                if new_state != r.state {
1123 
                    return fail(format!(
1124 
                        "attestation for {}/{} does not cover its current state",
1125 
                        remote_name, r.name
1126 
                    ));
1127 
                }
1128 
                let ar = self.store.put_attest(&sa.attest)?;
1129 
                for sig in &sa.sigs {
1130 
                    self.store.put_signature(&ar, sig)?;
1131 
                }
1132 
                self.record_serial(remote_name, &r.name, serial)?;
1133 
            }
1134 
            view.remotes
1135 
                .entry(remote_name.to_string())
1136 
                .or_default()
1137 
                .insert(r.name.clone(), state);
1138 
            report.push((r.name, r.heads, imported.len()));
1139 
        }
1140 
        let mut new_tags = 0;
1141 
        for t in &resp.tags {
1142 
            if view.tags.contains_key(&t.name) {
1143 
                continue;
1144 
            }
1145 
            // The tag's changes must be here: fetch them if the bookmarks did not bring them.
1146 
            let missing: Vec<ChangeHash> = t
1147 
                .heads
1148 
                .iter()
1149 
                .filter(|h| !self.store.has(h))
1150 
                .copied()
1151 
                .collect();
1152 
            if !missing.is_empty() {
1153 
                let needed = remote.negotiate(&self.known_heads(&view)?, &missing)?;
1154 
                let bundle = remote.fetch(&needed, max_blob)?;
1155 
                self.import_bundle(&bundle, false)?;
1156 
            }
1157 
            self.store.put_state(&StateObject::new(t.heads.clone()))?;
1158 
            self.adopt_tag(&mut view, t, policy.as_ref())
1159 
                .map_err(|e| RepoError::Msg(format!("{remote_name} {}: {e}", t.name)))?;
1160 
            new_tags += 1;
1161 
        }
1162 
        if view != op.view {
1163 
            self.record_op(&[op_ref], &format!("oxy fetch {remote_name}"), view)?;
1164 
        }
1165 
        let _ = self.run_hook(
1166 
            "post-fetch",
1167 
            &format!(
1168 
                "{{\"event\":\"post-fetch\",\"remote\":{},\"bookmarks\":{}}}",
1169 
                json_str(remote_name),
1170 
                json_array(report.iter().map(|(n, heads, _)| format!(
1171 
                    "{{\"name\":{},\"heads\":{}}}",
1172 
                    json_str(n),
1173 
                    json_array(heads.iter().map(|h| json_str(&h.to_hex())))
1174 
                )))
1175 
            ),
1176 
        );
1177 
        Ok(FetchReport {
1178 
            refs: report,
1179 
            unverified,
1180 
            new_tags,
1181 
        })
1182 
    }
1183
1184 
    /// Shallow fetch of the remote's bookmark: its checkpoint as our base,
1185 
    /// the changes within `depth` steps of its heads, and the boundary below.
1186 
    pub fn fetch_shallow(&self, remote_name: &str, depth: u32) -> Result<usize> {
1187 
        let remote = self.open_named_remote(remote_name)?;
1188 
        self.check_remote_id(remote.as_ref(), remote_name, false)?;
1189 
        let resp = remote.refs()?;
1190 
        let bookmark = self.config.bookmark.clone();
1191 
        if let Some(sp) = &resp.policy {
1192 
            self.adopt_policy_chain(&resp.history, sp, "oxy clone --depth")
1193 
                .map_err(|e| RepoError::Msg(format!("policy from {remote_name}: {e}")))?;
1194 
            self.record_policy_serial(remote_name, sp.policy.serial)?;
1195 
        }
1196 
        let Some(r) = resp.refs.into_iter().find(|r| r.name == bookmark) else {
1197 
            return fail(format!("{remote_name} has no bookmark {bookmark:?}"));
1198 
        };
1199 
        if r.heads.is_empty() {
1200 
            return Ok(0);
1201 
        }
1202 
        // Base: the remote's checkpoint of exactly these heads.
1203 
        let cp_bundle = remote.checkpoint(&r.heads)?;
1204 
        let mut cp_ref = None;
1205 
        for (ty, body) in &cp_bundle.objects {
1206 
            let put = self.store.put(*ty, body)?;
1207 
            if *ty == ObjectType::Checkpoint {
1208 
                cp_ref = Some(put);
1209 
            }
1210 
        }
1211 
        let Some(cp_ref) = cp_ref else {
1212 
            return fail(format!("{remote_name} sent no checkpoint"));
1213 
        };
1214 
        self.install_checkpoint(&bookmark, &cp_ref)?;
1215 
        // History window.
1216 
        let wanted = remote.shallow(&r.heads, depth)?;
1217 
        let bundle = remote.fetch(&wanted, self.config.max_blob)?;
1218 
        let imported = self.import_bundle_shallow(&bundle, false)?;
1219 
        if self.config.max_blob.is_some() {
1220 
            self.register_missing_blobs(&imported, remote_name)?;
1221 
        }
1222 
        self.refresh_boundary(&imported)?;
1223 
        if let Some(sa) = &r.attestation {
1224 
            let ar = self.store.put_attest(&sa.attest)?;
1225 
            for sig in &sa.sigs {
1226 
                self.store.put_signature(&ar, sig)?;
1227 
            }
1228 
            if let AttestBody::Ref { serial, .. } = sa.attest.body {
1229 
                self.record_serial(remote_name, &r.name, serial)?;
1230 
            }
1231 
        }
1232 
        let state = self.store.put_state(&StateObject::new(r.heads.clone()))?;
1233 
        let (op_ref, op) = self.head_op()?;
1234 
        let mut view = op.view.clone();
1235 
        view.remotes
1236 
            .entry(remote_name.to_string())
1237 
            .or_default()
1238 
            .insert(r.name.clone(), state);
1239 
        self.record_op(
1240 
            &[op_ref],
1241 
            &format!("oxy fetch {remote_name} --depth {depth}"),
1242 
            view,
1243 
        )?;
1244 
        Ok(imported.len())
1245 
    }
1246
1247 
    /// Fetch, then take the union of the local bookmark's state with the
1248 
    /// remote's: no merge change, conflicts become reified (spec §9.4).
1249 
    pub fn pull(&self, remote_name: &str) -> Result<PullReport> {
1250 
        self.fetch(remote_name)?;
1251 
        let (op_ref, op) = self.head_op()?;
1252 
        let bookmark = self.config.bookmark.clone();
1253 
        let local = self.heads_of(&op.view, &bookmark)?;
1254 
        let Some(remote_state) = op
1255 
            .view
1256 
            .remotes
1257 
            .get(remote_name)
1258 
            .and_then(|b| b.get(&bookmark))
1259 
            .copied()
1260 
        else {
1261 
            return Ok(PullReport {
1262 
                heads: local,
1263 
                changed: false,
1264 
                checked_out: false,
1265 
            });
1266 
        };
1267 
        let remote_heads = self.store.get_state(&remote_state)?.heads;
1268 
        let mut all = local.clone();
1269 
        all.extend(remote_heads);
1270 
        let st = self.load_state(&all)?;
1271 
        let mut heads = st.maximal(&all);
1272 
        heads.sort();
1273 
        let mut sorted_local = local.clone();
1274 
        sorted_local.sort();
1275 
        if heads == sorted_local {
1276 
            return Ok(PullReport {
1277 
                heads,
1278 
                changed: false,
1279 
                checked_out: false,
1280 
            });
1281 
        }
1282 
        let mut view = op.view.clone();
1283 
        view.bookmarks.insert(
1284 
            bookmark.clone(),
1285 
            self.store.put_state(&StateObject::new(heads.clone()))?,
1286 
        );
1287 
        self.record_op(&[op_ref], &format!("oxy pull {remote_name}"), view)?;
1288 
        // Follow along if the working copy was clean and on the old heads.
1289 
        let snap = self.snapshot("oxy pull")?;
1290 
        let clean = snap.wc.tree_ops.is_empty() && snap.wc.edits.is_empty();
1291 
        let mut base = snap.base.maximal(&snap.wc.deps);
1292 
        base.sort();
1293 
        let mut checked_out = false;
1294 
        if clean && base == sorted_local {
1295 
            self.checkout(&heads, false, "oxy pull (checkout)")?;
1296 
            checked_out = true;
1297 
        }
1298 
        Ok(PullReport {
1299 
            heads,
1300 
            changed: true,
1301 
            checked_out,
1302 
        })
1303 
    }
1304
1305 
    /// Push the current bookmark (spec §16.3), sealing this author's unsigned
1306 
    /// changes and attesting the reference when a key is available.
1307 
    /// Delete `bookmark` on a remote (spec §16.4): an update to the zero
1308 
    /// state, attested when we have an identity. The local bookmark, if
1309 
    /// any, is kept; only the remote-tracking entry goes.
1310 
    pub fn push_delete(&self, remote_name: &str, bookmark: &str) -> Result<Vec<RefResult>> {
1311 
        let remote = self.open_named_remote(remote_name)?;
1312 
        self.check_remote_id(remote.as_ref(), remote_name, true)?;
1313 
        let resp = remote.refs()?;
1314 
        let Some(r) = resp.refs.iter().find(|r| r.name == bookmark) else {
1315 
            return fail(format!("{remote_name} has no bookmark {bookmark}"));
1316 
        };
1317 
        if resp.policy.is_some() && self.secret_key()?.is_none() {
1318 
            return fail(format!("{remote_name} enforces a trust policy; deleting needs an identity (`oxy identity create`)"));
1319 
        }
1320 
        let attestation = match self.secret_key()? {
1321 
            Some(_) => Some(self.sign_attest(&Attest {
1322 
                repo: self.id()?,
1323 
                hlc: Hlc::now(),
1324 
                body: AttestBody::Ref {
1325 
                    name: bookmark.to_string(),
1326 
                    old_state: r.state,
1327 
                    new_state: ObjectRef::ZERO,
1328 
                    serial: r.last_serial.unwrap_or(0) + 1,
1329 
                },
1330 
            })?),
1331 
            None => None,
1332 
        };
1333 
        let results = remote.push(
1334 
            Bundle::default(),
1335 
            vec![RefUpdate {
1336 
                name: bookmark.to_string(),
1337 
                old_state: r.state,
1338 
                new_state: ObjectRef::ZERO,
1339 
                force: true,
1340 
                attestation,
1341 
            }],
1342 
            None,
1343 
            vec![],
1344 
        )?;
1345 
        if results.iter().any(|x| x.ok && x.name == bookmark) {
1346 
            let (op_ref, op) = self.head_op()?;
1347 
            let mut view = op.view.clone();
1348 
            if let Some(m) = view.remotes.get_mut(remote_name) {
1349 
                m.remove(bookmark);
1350 
            }
1351 
            self.record_op(
1352 
                &[op_ref],
1353 
                &format!("oxy push {remote_name} --delete {bookmark}"),
1354 
                view,
1355 
            )?;
1356 
        }
1357 
        Ok(results)
1358 
    }
1359
1360 
    pub fn push(&self, remote_name: &str, force: bool) -> Result<Vec<RefResult>> {
1361 
        let bookmark = self.config.bookmark.clone();
1362 
        self.push_bookmark(remote_name, &bookmark, force)
1363 
    }
1364
1365 
    /// `push` for a named bookmark (`oxy push -b NAME`).
1366 
    pub fn push_bookmark(
1367 
        &self,
1368 
        remote_name: &str,
1369 
        bookmark: &str,
1370 
        force: bool,
1371 
    ) -> Result<Vec<RefResult>> {
1372 
        let (op_ref, op) = self.head_op()?;
1373 
        if !op.view.bookmarks.contains_key(bookmark) {
1374 
            return fail(format!("no bookmark {bookmark}"));
1375 
        }
1376 
        let bookmark = bookmark.to_string();
1377 
        let local_heads = self.heads_of(&op.view, &bookmark)?;
1378 
        // pre-push hook: may veto before the remote is contacted.
1379 
        self.run_hook(
1380 
            "pre-push",
1381 
            &format!(
1382 
                "{{\"event\":\"pre-push\",\"remote\":{},\"bookmark\":{},\"heads\":{}}}",
1383 
                json_str(remote_name),
1384 
                json_str(&bookmark),
1385 
                json_array(local_heads.iter().map(|h| json_str(&h.to_hex())))
1386 
            ),
1387 
        )?;
1388 
        let remote = self.open_named_remote(remote_name)?;
1389 
        self.check_remote_id(remote.as_ref(), remote_name, true)?;
1390 
        let resp = remote.refs()?;
1391 
        let local_policy = self.current_policy()?.map(|(_, sp)| sp);
1392 
        let resp_policy_serial = resp.policy.as_ref().map(|p| p.policy.serial);
1393 
        let policy_to_send = match (&local_policy, &resp.policy) {
1394 
            (Some(l), Some(r)) if l.policy.serial > r.policy.serial => Some(l.clone()),
1395 
            (Some(l), None) => Some(l.clone()),
1396 
            (Some(l), Some(r)) if l.policy.serial < r.policy.serial => {
1397 
                return fail(format!(
1398 
                    "{remote_name} has a newer policy (serial {}); fetch first",
1399 
                    r.policy.serial
1400 
                ));
1401 
            }
1402 
            _ => None,
1403 
        };
1404 
        let remote_has_policy = resp.policy.is_some() || policy_to_send.is_some();
1405 
        if remote_has_policy && self.secret_key()?.is_none() {
1406 
            return fail(format!("{remote_name} enforces a trust policy; pushing needs an identity (`oxy identity create`)"));
1407 
        }
1408 
        let remote_tags: BTreeSet<String> = resp.tags.iter().map(|t| t.name.clone()).collect();
1409 
        let tags_to_send: Vec<crate::protocol::TagRef> = self
1410 
            .tag_refs()?
1411 
            .into_iter()
1412 
            .filter(|t| !remote_tags.contains(&t.name))
1413 
            .collect();
1414 
        let refs = resp.refs;
1415 
        let empty = self.store.put_state(&StateObject::new(vec![]))?;
1416 
        let (remote_state, remote_heads, last_serial) =
1417 
            match refs.iter().find(|r| r.name == bookmark) {
1418 
                Some(r) => (r.state, r.heads.clone(), r.last_serial),
1419 
                None => (empty, vec![], None),
1420 
            };
1421 
        let new_state = self
1422 
            .store
1423 
            .put_state(&StateObject::new(local_heads.clone()))?;
1424 
        // A push that carries a policy re-attests the bookmark even when its
1425 
        // state is unchanged, so the current attestation is always by a key
1426 
        // the current policy authorizes (a revoked key's attestation would
1427 
        // otherwise be refused by every later fetch).
1428 
        if new_state == remote_state && policy_to_send.is_none() && tags_to_send.is_empty() {
1429 
            return Ok(vec![RefResult {
1430 
                name: bookmark,
1431 
                ok: true,
1432 
                reason: "already up to date".into(),
1433 
            }]);
1434 
        }
1435 
        for h in &remote_heads {
1436 
            if !self.store.has(h) {
1437 
                return fail(format!(
1438 
                    "the remote has change {} which you do not; pull first (`oxy pull {remote_name}`), then push again",
1439 
                    h.short(12)
1440 
                ));
1441 
            }
1442 
        }
1443 
        if !force {
1444 
            let closure = self.closure_in_store(&local_heads)?;
1445 
            if let Some(h) = remote_heads.iter().find(|h| !closure.contains(h)) {
1446 
                return fail(format!("not a fast-forward: remote head {} is not in your state; pull first or use --force", h.short(12)));
1447 
            }
1448 
        }
1449 
        let to_send = self.negotiate(&remote_heads, &local_heads)?;
1450 
        let mut bundle = self.bundle_for(&to_send)?;
1451 
        let key = self.secret_key()?.map(|(k, _)| k);
1452 
        if let Some(key) = key {
1453 
            // Seal this author's changes that carry no valid authenticator,
1454 
            // and adopt anonymous ones (zero author, spec §14.4).
1455 
            let mut unsigned = Vec::new();
1456 
            for h in &to_send {
1457 
                let c = self.store.get_change(h)?;
1458 
                if (c.author == key || c.author.is_zero())
1459 
                    && !matches!(self.authenticate_change(h)?, SignatureStatus::Valid { .. })
1460 
                {
1461 
                    unsigned.push(*h);
1462 
                }
1463 
            }
1464 
            for chunk in unsigned.chunks(crate::attest::MAX_SEAL_HASHES) {
1465 
                let sa = self.sign_attest(&Attest::seal(self.id()?, chunk.to_vec()))?;
1466 
                bundle.attests.push(sa);
1467 
            }
1468 
            bundle = self.bundle_for(&to_send)?;
1469 
        }
1470 
        bundle.objects.push((
1471 
            ObjectType::State,
1472 
            StateObject::new(local_heads.clone()).encode(),
1473 
        ));
1474 
        let attestation = match key {
1475 
            Some(_) => Some(self.sign_attest(&Attest {
1476 
                repo: self.id()?,
1477 
                hlc: Hlc::now(),
1478 
                body: AttestBody::Ref {
1479 
                    name: bookmark.clone(),
1480 
                    old_state: remote_state,
1481 
                    new_state,
1482 
                    serial: next_serial(last_serial),
1483 
                },
1484 
            })?),
1485 
            None => None,
1486 
        };
1487 
        let serial = attestation.as_ref().and_then(|a| match a.attest.body {
1488 
            AttestBody::Ref { serial, .. } => Some(serial),
1489 
            _ => None,
1490 
        });
1491 
        let sent_serial = policy_to_send.as_ref().map(|p| p.policy.serial);
1492 
        // Tag states must be present on the remote: bundle their changes too.
1493 
        for t in &tags_to_send {
1494 
            let extra = self.negotiate(&remote_heads, &t.heads)?;
1495 
            let extra: Vec<ChangeHash> =
1496 
                extra.into_iter().filter(|h| !to_send.contains(h)).collect();
1497 
            if !extra.is_empty() {
1498 
                let more = self.bundle_for(&extra)?;
1499 
                bundle.changes.extend(more.changes);
1500 
                bundle.attests.extend(more.attests);
1501 
                bundle.objects.extend(more.objects);
1502 
            }
1503 
            bundle.objects.push((
1504 
                ObjectType::State,
1505 
                StateObject::new(t.heads.clone()).encode(),
1506 
            ));
1507 
        }
1508 
        if let Some(l) = &policy_to_send {
1509 
            let remote_serial = resp_policy_serial;
1510 
            bundle.policies = self
1511 
                .policy_history()?
1512 
                .into_iter()
1513 
                .filter(|sp| {
1514 
                    remote_serial.is_none_or(|r| sp.policy.serial > r)
1515 
                        && sp.policy.serial < l.policy.serial
1516 
                })
1517 
                .collect();
1518 
        }
1519 
        let results = remote.push(
1520 
            bundle,
1521 
            vec![RefUpdate {
1522 
                name: bookmark.clone(),
1523 
                old_state: remote_state,
1524 
                new_state,
1525 
                force,
1526 
                attestation,
1527 
            }],
1528 
            policy_to_send,
1529 
            tags_to_send,
1530 
        )?;
1531 
        if let (Some(serial), true) = (
1532 
            sent_serial,
1533 
            results.iter().any(|r| r.ok && r.name == "policy"),
1534 
        ) {
1535 
            self.record_policy_serial(remote_name, serial)?;
1536 
        }
1537 
        if results.iter().any(|r| r.ok && r.name == bookmark) {
1538 
            let mut view = op.view.clone();
1539 
            view.remotes
1540 
                .entry(remote_name.to_string())
1541 
                .or_default()
1542 
                .insert(bookmark.clone(), new_state);
1543 
            self.record_op(&[op_ref], &format!("oxy push {remote_name}"), view)?;
1544 
            if let Some(s) = serial {
1545 
                self.record_serial(remote_name, &bookmark, s)?;
1546 
            }
1547 
        }
1548 
        Ok(results)
1549 
    }
1550
1551 
    /// Clone a remote into `dest`: same repository ID, `origin` remote,
1552 
    /// bookmark set to the remote's, working copy checked out.
1553 
    pub fn clone(url: &str, dest: &Path) -> Result<Repo> {
1554 
        Self::clone_with(url, dest, None, &[])
1555 
    }
1556
1557 
    /// Clone, leaving blobs above `max_blob` bytes to be fetched on first
1558 
    /// read, and materializing only `sparse` paths (which implies lazy blobs
1559 
    /// unless a size is given, so out-of-scope binaries are never fetched).
1560 
    pub fn clone_with(
1561 
        url: &str,
1562 
        dest: &Path,
1563 
        max_blob: Option<u64>,
1564 
        sparse: &[String],
1565 
    ) -> Result<Repo> {
1566 
        Self::clone_full(url, dest, max_blob, sparse, None)
1567 
    }
1568
1569 
    /// Shallow clone (spec §17): a checkpoint of the bookmark's heads plus the
1570 
    /// changes within `depth` steps of them; the rest is the boundary.
1571 
    pub fn clone_shallow(
1572 
        url: &str,
1573 
        dest: &Path,
1574 
        depth: u32,
1575 
        max_blob: Option<u64>,
1576 
        sparse: &[String],
1577 
    ) -> Result<Repo> {
1578 
        Self::clone_full(url, dest, max_blob, sparse, Some(depth))
1579 
    }
1580
1581 
    fn clone_full(
1582 
        url: &str,
1583 
        dest: &Path,
1584 
        max_blob: Option<u64>,
1585 
        sparse: &[String],
1586 
        depth: Option<u32>,
1587 
    ) -> Result<Repo> {
1588 
        let options = RemoteOptions {
1589 
            token: std::env::var("OXY_TOKEN").ok(),
1590 
            ca: std::env::var("OXY_CA").ok().map(PathBuf::from),
1591 
            repo_id: None,
1592 
        };
1593 
        let remote = open_remote(url, &options)?;
1594 
        let id = remote.repo_id()?;
1595 
        if id == crate::protocol::UNBOUND_ID {
1596 
            return fail(format!(
1597 
                "{url} is empty and unbound: push a repository to it first"
1598 
            ));
1599 
        }
1600 
        let mut repo = Repo::init_with_id(dest, id)?;
1601 
        repo.config.set("remote.origin.url", url)?;
1602 
        if let Some(m) = max_blob {
1603 
            repo.config.set("filter.max-blob", &m.to_string())?;
1604 
        } else if !sparse.is_empty() {
1605 
            repo.config.set("filter.max-blob", "0")?;
1606 
        }
1607 
        if !sparse.is_empty() {
1608 
            repo.config.set("filter.paths", &sparse.join(","))?;
1609 
        }
1610 
        repo.save_config()?;
1611 
        if let Some(depth) = depth {
1612 
            repo.fetch_shallow("origin", depth)?;
1613 
        } else {
1614 
            repo.fetch("origin")?;
1615 
        }
1616 
        let (op_ref, op) = repo.head_op()?;
1617 
        let bookmark = repo.config.bookmark.clone();
1618 
        if let Some(state) = op
1619 
            .view
1620 
            .remotes
1621 
            .get("origin")
1622 
            .and_then(|b| b.get(&bookmark))
1623 
            .copied()
1624 
        {
1625 
            let heads = repo.store.get_state(&state)?.heads;
1626 
            let mut view = op.view.clone();
1627 
            view.bookmarks.insert(bookmark, state);
1628 
            repo.record_op(&[op_ref], &format!("oxy clone {url}"), view)?;
1629 
            repo.checkout(&heads, false, "oxy clone (checkout)")?;
1630 
        }
1631 
        Ok(repo)
1632 
    }
1633 
}
1634
1635 
/// The serial of a reference's next attestation: one more than the last the
1636 
/// remote reports, or, for a bookmark the remote does not have, the clock in
1637 
/// milliseconds, so a bookmark created again after a deletion goes past the
1638 
/// deletion's serial the remote keeps.
1639 
fn next_serial(last: Option<u64>) -> u64 {
1640 
    match last {
1641 
        Some(l) => l + 1,
1642 
        None => Hlc::now().wall_ms.max(1),
1643 
    }
1644 
}