OXYGENHUB

Coverage / crates/oxy-core/src/repo/policy.rs 79.4%

316 of 398 lines run, 47 of 88 functions · run #311 on main · run missed

1
//! Trust policy management and enforcement (spec §14.5).
2
//!
3
//! A repository with a policy verifies everything it receives: every change
4
//! must be authenticated by a key the policy authorizes for the bookmark,
5
//! every bookmark update must carry an attestation by such a key, and a new
6
//! policy must be signed by a threshold of the roots of the policy it replaces.
7
8
use super::*;
9
use crate::identity::SecretKey;
10
use crate::policy::{Policy, Require, Rule};
11
use crate::protocol::SignedPolicy;
12
13
/// One year, the default policy lifetime.
14
const POLICY_LIFETIME_MS: u64 = 365 * 24 * 60 * 60 * 1000;
15
16
/// A signed policy update: applied when it met the root threshold, else a
17
/// proposal carrying the signatures gathered so far (spec §14.5).
18
#[derive(Clone, Debug)]
19
pub struct PolicyUpdate {
20
    pub policy: Policy,
21
    pub sigs: Vec<Signature>,
22
    pub applied: bool,
23
}
24
25
impl PolicyUpdate {
263×
    pub fn signed(&self) -> SignedPolicy {
273×
        SignedPolicy {
283×
            policy: self.policy.clone(),
293×
            sigs: self.sigs.clone(),
303×
        }
313×
    }
32
}
33
34
impl Repo {
35
    /// The current policy and its signatures, if the repository has one.
363522×
    pub fn current_policy(&self) -> Result<Option<(ObjectRef, SignedPolicy)>> {
373522×
        let Some(r) = self.view()?.policy else {
383223×
            return Ok(None);
39
        };
40299×
        let policy = Policy::decode(&self.store.get_typed(&r, ObjectType::Policy)?)?;
41
        Ok(Some((
42299×
            r,
43
            SignedPolicy {
44299×
                policy,
45299×
                sigs: self.store.signatures(&r)?,
46
            },
47
        )))
483522×
    }
49
50
    /// Store a policy with its signatures and point the `policy` reference at it.
5160×
    pub(crate) fn set_policy(&self, sp: &SignedPolicy, command: &str) -> Result<ObjectRef> {
5260×
        let r = self.store.put(ObjectType::Policy, &sp.policy.encode())?;
5384×
        for sig in &sp.sigs {
5484×
            self.store.put_signature(&r, sig)?;
55
        }
56142×
        for id in &sp.policy.identities {
57142×
            self.store.put_identity(id)?;
58
        }
5960×
        let dir = self.oxy.join("policies");
6060×
        fs::create_dir_all(&dir)?;
6160×
        write_atomic(
6260×
            &dir.join(format!("{:020}", sp.policy.serial)),
6360×
            r.to_hex().as_bytes(),
640×
        )?;
6560×
        let (op_ref, op) = self.head_op()?;
6660×
        if op.view.policy != Some(r) {
6760×
            let mut view = op.view.clone();
6860×
            view.policy = Some(r);
6960×
            self.record_op(&[op_ref], command, view)?;
700×
        }
7160×
        Ok(r)
7260×
    }
73
74
    /// Every policy this repository has applied, ascending by serial, with
75
    /// its signatures. Policies applied before this index existed are
76
    /// missing from it, except the current one.
771006×
    pub fn policy_history(&self) -> Result<Vec<SignedPolicy>> {
781006×
        let mut out: BTreeMap<u64, SignedPolicy> = BTreeMap::new();
791006×
        if let Ok(rd) = fs::read_dir(self.oxy.join("policies")) {
80118×
            for e in rd.flatten() {
81118×
                let Ok(hex) = fs::read_to_string(e.path()) else {
820×
                    continue;
83
                };
84118×
                let Some(r) = ObjectRef::from_hex(hex.trim()) else {
850×
                    continue;
86
                };
87118×
                let Ok(bytes) = self.store.get_typed(&r, ObjectType::Policy) else {
880×
                    continue;
89
                };
90118×
                let policy = Policy::decode(&bytes)?;
91118×
                out.insert(
92118×
                    policy.serial,
93
                    SignedPolicy {
94118×
                        policy,
95118×
                        sigs: self.store.signatures(&r)?,
96
                    },
97
                );
98
            }
99955×
        }
1001006×
        if let Some((_, sp)) = self.current_policy()? {
10151×
            out.insert(sp.policy.serial, sp);
102955×
        }
1031006×
        Ok(out.into_values().collect())
1041006×
    }
105
106
    /// Verify and apply a chain of policies ending in `newest`, each
107
    /// against the one before it (spec §14.5). `chain` holds earlier
108
    /// policies in any order; only those after the current serial are used.
10929×
    pub(crate) fn adopt_policy_chain(
11029×
        &self,
11129×
        chain: &[SignedPolicy],
11229×
        newest: &SignedPolicy,
11329×
        command: &str,
11429×
    ) -> std::result::Result<(), String> {
11529×
        let mut current = self
11629×
            .current_policy()
11729×
            .map_err(|e| e.to_string())?
11829×
            .map(|(_, sp)| sp.policy);
11929×
        let mut steps: Vec<&SignedPolicy> = chain
12029×
            .iter()
12129×
            .filter(|sp| {
12220×
                current.as_ref().is_none_or(|c| sp.policy.serial > c.serial)
1239×
                    && sp.policy.serial < newest.policy.serial
12420×
            })
12529×
            .collect();
12629×
        steps.sort_by_key(|sp| sp.policy.serial);
12729×
        steps.push(newest);
12838×
        for sp in steps {
12938×
            self.check_policy(sp, current.as_ref())?;
13036×
            self.set_policy(
13136×
                sp,
13236×
                &format!("{command} (policy serial {})", sp.policy.serial),
133
            )
13436×
            .map_err(|e| e.to_string())?;
13536×
            current = Some(sp.policy.clone());
136
        }
13727×
        Ok(())
13829×
    }
139
140
    /// Validate an incoming policy against the one we trust (`None` when
141
    /// bootstrapping: the policy then vouches for itself).
14238×
    pub fn check_policy(
14338×
        &self,
14438×
        sp: &SignedPolicy,
14538×
        trusted: Option<&Policy>,
14638×
    ) -> std::result::Result<(), String> {
14738×
        if sp.policy.repo != self.id().map_err(|e| e.to_string())? {
1480×
            return Err("policy is for a different repository".into());
14938×
        }
15038×
        if let Some(t) = trusted {
15126×
            if sp.policy.serial <= t.serial {
1521×
                return Err(format!(
1531×
                    "policy serial {} is not greater than the current {}",
1541×
                    sp.policy.serial, t.serial
1551×
                ));
15625×
            }
15712×
        }
15837×
        match trusted {
15925×
            Some(t) => sp.policy.verify_signatures(&sp.sigs, t)?,
16012×
            None => vec![sp.policy.verify_bootstrap(&sp.sigs)?],
161
        };
16236×
        Ok(())
16338×
    }
164
165
    /// Sign `policy` with the configured key and apply it if the current
166
    /// policy's root threshold is met; otherwise return it as a proposal.
16716×
    fn sign_policy(&self, policy: Policy, command: &str) -> Result<PolicyUpdate> {
16816×
        let Some((key, sk)) = self.secret_key()? else {
1690×
            return fail("no secret key: run `oxy identity create` first");
170
        };
17116×
        self.sign_policy_with(policy, &[(key, &sk)], command)
17216×
    }
173
174
    /// Sign with every listed key; the first must be a root of the current
175
    /// policy (the others may be roots of the new policy only, so that a
176
    /// fresh clone can bootstrap from it).
17724×
    pub(crate) fn sign_policy_with(
17824×
        &self,
17924×
        policy: Policy,
18024×
        signers: &[(KeyId, &SecretKey)],
18124×
        command: &str,
18224×
    ) -> Result<PolicyUpdate> {
18324×
        let trusted = self
18424×
            .current_policy()?
18524×
            .map(|(_, sp)| sp.policy)
18624×
            .unwrap_or_else(|| policy.clone());
18724×
        if !signers
18824×
            .first()
18924×
            .is_some_and(|(k, _)| trusted.roots.contains(k))
190
        {
1910×
            return fail("your key is not a root key of the current policy");
19224×
        }
19324×
        let target = policy.hash();
19424×
        let sigs = signers
19524×
            .iter()
19632×
            .map(|(k, sk)| sk.sign(Domain::Policy, k, &target))
19724×
            .collect();
19824×
        self.gather(SignedPolicy { policy, sigs }, &trusted, command)
19924×
    }
200
201
    /// Apply `sp` when its signatures meet `trusted`'s threshold.
20226×
    fn gather(&self, sp: SignedPolicy, trusted: &Policy, command: &str) -> Result<PolicyUpdate> {
20326×
        let applied = sp.policy.verify_signatures(&sp.sigs, trusted).is_ok();
20426×
        if applied {
20524×
            self.set_policy(&sp, command)?;
2062×
        }
20726×
        Ok(PolicyUpdate {
20826×
            policy: sp.policy,
20926×
            sigs: sp.sigs,
21026×
            applied,
21126×
        })
21226×
    }
213
214
    /// Add your signature to a proposal made by another root holder; the
215
    /// policy is applied once the current root threshold is met.
2163×
    pub fn policy_sign(&self, proposal: SignedPolicy) -> Result<PolicyUpdate> {
2173×
        let Some((key, sk)) = self.secret_key()? else {
2180×
            return fail("no secret key: run `oxy identity create` first");
219
        };
2203×
        let Some((_, current)) = self.current_policy()? else {
2210×
            return fail("this repository has no policy; run `oxy policy init` or fetch one");
222
        };
2233×
        if proposal.policy.repo != self.id()? {
2240×
            return fail("the proposal is for a different repository");
2253×
        }
2263×
        if proposal.policy.serial <= current.policy.serial {
2271×
            return fail(format!(
228
                "the proposal's serial {} is not greater than the current {}",
229
                proposal.policy.serial, current.policy.serial
230
            ));
2312×
        }
2322×
        if !current.policy.roots.contains(&key) {
2330×
            return fail("your key is not a root key of the current policy");
2342×
        }
2352×
        let mut sigs: Vec<Signature> = proposal.sigs.into_iter().filter(|s| s.key != key).collect();
2362×
        sigs.push(sk.sign(Domain::Policy, &key, &proposal.policy.hash()));
2372×
        self.gather(
2382×
            SignedPolicy {
2392×
                policy: proposal.policy,
2402×
                sigs,
2412×
            },
2422×
            &current.policy,
2432×
            "oxy policy sign",
244
        )
2453×
    }
246
247
    /// Create the initial policy with the configured identity as sole root.
2489×
    pub fn policy_init(&self) -> Result<PolicyUpdate> {
2499×
        if self.current_policy()?.is_some() {
2500×
            return fail("this repository already has a policy");
2519×
        }
2529×
        let Some((key, _)) = self.secret_key()? else {
2530×
            return fail("no secret key: run `oxy identity create` first");
254
        };
2559×
        let identity = self.identity(&key)?;
2569×
        let policy = Policy::single_root(
2579×
            self.id()?,
2589×
            identity,
2599×
            Hlc::now().wall_ms + POLICY_LIFETIME_MS,
260
        );
2619×
        self.sign_policy(policy, "oxy policy init")
2629×
    }
263
264
    /// Make `identity` a root key.
2652×
    pub fn policy_root_add(&self, identity: Identity) -> Result<PolicyUpdate> {
2662×
        let mut p = self.next_policy()?;
2672×
        let key = identity.hash();
2682×
        if p.roots.contains(&key) {
2691×
            return fail(format!("{} is already a root", key.short(12)));
2701×
        }
2711×
        p.roots.push(key);
2721×
        p.roots.sort();
2731×
        p.revoked.retain(|k| k != &key);
2741×
        if p.identity(&key).is_none() {
2751×
            p.identities.push(identity);
2761×
        }
2771×
        self.sign_policy(p, &format!("oxy policy root add {}", key.short(12)))
2782×
    }
279
280
    /// Drop a root key; the remaining roots must still meet the threshold.
2810×
    pub fn policy_root_remove(&self, key: &KeyId) -> Result<PolicyUpdate> {
2820×
        let mut p = self.next_policy()?;
2830×
        if !p.roots.contains(key) {
2840×
            return fail(format!("{} is not a root", key.short(12)));
2850×
        }
2860×
        p.roots.retain(|k| k != key);
2870×
        if (p.roots.len() as u32) < p.root_threshold {
2880×
            return fail(format!(
289
                "removing it would leave {} root(s) for a threshold of {}",
2900×
                p.roots.len(),
291
                p.root_threshold
292
            ));
2930×
        }
2940×
        self.sign_policy(p, &format!("oxy policy root remove {}", key.short(12)))
2950×
    }
296
297
    /// Require `n` root signatures on future policy updates.
2982×
    pub fn policy_set_threshold(&self, n: u32) -> Result<PolicyUpdate> {
2992×
        let mut p = self.next_policy()?;
3002×
        if n == 0 || n as usize > p.roots.len() {
3011×
            return fail(format!(
302
                "the threshold must be between 1 and the number of roots ({})",
3031×
                p.roots.len()
304
            ));
3051×
        }
3061×
        p.root_threshold = n;
3071×
        self.sign_policy(p, &format!("oxy policy root threshold {n}"))
3082×
    }
309
31019×
    pub(crate) fn next_policy(&self) -> Result<Policy> {
31119×
        let Some((_, sp)) = self.current_policy()? else {
3120×
            return fail("this repository has no policy; run `oxy policy init`");
313
        };
31419×
        let mut p = sp.policy;
31519×
        p.serial += 1;
31619×
        p.expires = Hlc::now().wall_ms + POLICY_LIFETIME_MS;
31719×
        Ok(p)
31819×
    }
319
320
    /// Let `identity` update references matching `pattern` (default every reference).
3212×
    pub fn policy_grant(&self, identity: Identity, pattern: Option<&str>) -> Result<PolicyUpdate> {
3222×
        let mut p = self.next_policy()?;
3232×
        let key = identity.hash();
3242×
        let pattern = pattern.unwrap_or("*");
3252×
        p.revoked.retain(|k| k != &key);
3262×
        match p.rules.iter_mut().find(|r| r.pattern == pattern) {
3272×
            Some(rule) => {
3282×
                if !rule.keys.contains(&key) {
3292×
                    rule.keys.push(key);
3302×
                    rule.keys.sort();
3312×
                }
332
            }
3330×
            None => p.rules.push(Rule {
3340×
                pattern: pattern.into(),
3350×
                keys: vec![key],
3360×
                threshold: 1,
3370×
                require: Require::Any,
3380×
                allow_conflicts: true,
3390×
                subjects: vec![],
3400×
            }),
341
        }
3422×
        if p.identity(&key).is_none() {
3432×
            p.identities.push(identity);
3442×
        }
3452×
        self.sign_policy(p, &format!("oxy policy grant {}", key.short(12)))
3462×
    }
347
348
    /// Let holders of certificates `issuer` gives, for subjects matching
349
    /// `subject`, sign within `scope` on `pattern` (default every
350
    /// bookmark; §14.7). The issuer's identity is embedded so verifiers need
351
    /// no fetch.
3521×
    pub fn policy_grant_subject(
3531×
        &self,
3541×
        subject: &str,
3551×
        issuer: Identity,
3561×
        scope: crate::identity::Scope,
3571×
        pattern: Option<&str>,
3581×
    ) -> Result<PolicyUpdate> {
3591×
        if subject.trim().is_empty() {
3600×
            return fail("a subject pattern is needed, such as repo:OWNER/NAME:bookmark:main");
3611×
        }
3621×
        let mut p = self.next_policy()?;
3631×
        let key = issuer.hash();
3641×
        let pattern = pattern.unwrap_or("*");
3651×
        let grant = crate::policy::SubjectGrant {
3661×
            pattern: subject.into(),
3671×
            issuer: key,
3681×
            scope,
3691×
        };
3701×
        match p.rules.iter_mut().find(|r| r.pattern == pattern) {
3711×
            Some(rule) => {
3721×
                rule.subjects
3731×
                    .retain(|g| !(g.pattern == grant.pattern && g.issuer == grant.issuer));
3741×
                rule.subjects.push(grant);
375
            }
3760×
            None => p.rules.push(Rule {
3770×
                pattern: pattern.into(),
3780×
                keys: vec![],
3790×
                threshold: 1,
3800×
                require: Require::Any,
3810×
                allow_conflicts: true,
3820×
                subjects: vec![grant],
3830×
            }),
384
        }
3851×
        if p.identity(&key).is_none() {
3861×
            p.identities.push(issuer);
3871×
        }
3881×
        self.sign_policy(p, &format!("oxy policy grant-subject {subject}"))
3891×
    }
390
391
    /// Revoke `key`: it may no longer update anything, and existing rules
392
    /// drop it. A root key can be revoked by another root as long as the
393
    /// remaining roots still meet the threshold.
3944×
    pub fn policy_revoke(&self, key: &KeyId) -> Result<PolicyUpdate> {
3954×
        let mut p = self.next_policy()?;
3964×
        if p.roots.contains(key) {
3972×
            let own = self.secret_key()?.map(|(k, _)| k);
3982×
            if own == Some(*key) {
3991×
                return fail("a root cannot revoke itself; have another root revoke it, or remove it with `oxy policy root remove` first");
4001×
            }
4012×
            p.roots.retain(|k| k != key);
4021×
            if (p.roots.len() as u32) < p.root_threshold {
4031×
                return fail(format!(
404
                    "revoking it would leave {} root(s) for a threshold of {}",
4051×
                    p.roots.len(),
406
                    p.root_threshold
407
                ));
4080×
            }
4092×
        }
4102×
        for r in &mut p.rules {
4114×
            r.keys.retain(|k| k != key);
412
        }
4132×
        p.rules.retain(|r| !r.keys.is_empty());
4142×
        if !p.revoked.contains(key) {
4152×
            p.revoked.push(*key);
4162×
            p.revoked.sort();
4172×
        }
4182×
        self.sign_policy(p, &format!("oxy policy revoke {}", key.short(12)))
4194×
    }
420
421
    /// Whether `change` may be part of `reference` under `policy`: it must be
422
    /// authenticated (by its author or a delegate) with a key the matching
423
    /// rule lists, using the authenticator kind the rule requires. A rule key
424
    /// covers its rotation predecessors, and a delegate's signature counts
425
    /// for the author it acts for.
42617×
    pub fn change_allowed(
42717×
        &self,
42817×
        hash: &ChangeHash,
42917×
        policy: &Policy,
43017×
        reference: &str,
43117×
    ) -> std::result::Result<(), String> {
43217×
        let rule = policy
43317×
            .rule_for(reference)
43417×
            .ok_or_else(|| format!("no policy rule matches {reference:?}"))?;
43517×
        match self.authenticate_change(hash).map_err(|e| e.to_string())? {
43617×
            SignatureStatus::Valid { key, sealed, .. } => {
43717×
                if policy.is_revoked(&key) {
4380×
                    return Err(format!(
4390×
                        "change {} is signed by revoked key {}",
4400×
                        hash.short(12),
4410×
                        key.short(12)
4420×
                    ));
44317×
                }
44417×
                let author = self
44517×
                    .store
44617×
                    .get_change(hash)
44717×
                    .map(|c| c.author)
44817×
                    .map_err(|e| e.to_string())?;
44917×
                let principal = if author.is_zero() { key } else { author };
45017×
                let covered = rule
45117×
                    .keys
45217×
                    .iter()
45317×
                    .any(|k| policy.succeeds(k, &key) || policy.succeeds(k, &principal));
45417×
                if !covered {
4550×
                    return Err(format!(
4560×
                        "change {} is signed by {}, which may not update {reference:?}",
4570×
                        hash.short(12),
4580×
                        key.short(12)
4590×
                    ));
46017×
                }
46117×
                match (rule.require, sealed) {
4620×
                    (Require::Signed, true) => Err(format!(
4630×
                        "{reference:?} requires individually signed changes; {} is only sealed",
4640×
                        hash.short(12)
4650×
                    )),
4660×
                    (Require::Sealed, false) => Err(format!(
4670×
                        "{reference:?} requires sealed changes; {} is individually signed",
4680×
                        hash.short(12)
4690×
                    )),
47017×
                    _ => Ok(()),
471
                }
472
            }
473
            SignatureStatus::Unsigned => {
4740×
                Err(format!("change {} is not signed or sealed", hash.short(12)))
475
            }
4760×
            SignatureStatus::Invalid(e) => Err(format!("change {}: {e}", hash.short(12))),
477
        }
47817×
    }
479
480
    /// Check every change that `new` adds over `old` for `reference`.
48124×
    pub(crate) fn state_allowed(
48224×
        &self,
48324×
        old_heads: &[ChangeHash],
48424×
        new_heads: &[ChangeHash],
48524×
        policy: &Policy,
48624×
        reference: &str,
48724×
    ) -> std::result::Result<(), String> {
48824×
        let added = self
48924×
            .negotiate(old_heads, new_heads)
49024×
            .map_err(|e| e.to_string())?;
49124×
        for h in &added {
49216×
            self.change_allowed(h, policy, reference)?;
493
        }
49424×
        if let Some(rule) = policy.rule_for(reference) {
49524×
            if !rule.allow_conflicts && !added.is_empty() {
4960×
                let st = self.load_state(new_heads).map_err(|e| e.to_string())?;
4970×
                if st.materialize().is_conflicted() {
4980×
                    return Err(format!("{reference:?} does not allow conflicted states"));
4990×
                }
50024×
            }
5010×
        }
50224×
        Ok(())
50324×
    }
504
}