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motr-enclave/docs/UCAN_SCHEMA_PROPOSAL.md

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# UCAN v1.0.0-rc.1 Schema Proposal
## Overview
This document proposes schema changes to migrate from JWT-based UCAN to v1.0.0-rc.1 envelope format.
## Design Principles
1. **Single Database** - All data in one SQLite for WASM portability
2. **CID-based Lookup** - Primary key is content identifier (immutable)
3. **Binary Storage** - DAG-CBOR envelopes stored as BLOBs
4. **Indexed Fields** - Extract key fields for efficient queries
5. **DID Ownership** - Foreign key to did_documents for access control
## Architecture
```
┌─────────────────────────────────────────────────────────────────┐
│ WASM Plugin (Enclave) │
├─────────────────────────────────────────────────────────────────┤
│ │
│ ┌──────────────┐ ┌──────────────┐ ┌──────────────┐ │
│ │ WebAuthn │ │ DID │ │ UCAN │ │
│ │ (AuthN) │ │ (Identity) │ │ (AuthZ) │ │
│ └──────┬───────┘ └──────┬───────┘ └──────┬───────┘ │
│ │ │ │ │
│ ▼ ▼ ▼ │
│ ┌──────────────────────────────────────────────────────────┐ │
│ │ SQLite Database │ │
│ │ ┌────────────┐ ┌────────────┐ ┌─────────────────────┐ │ │
│ │ │credentials │ │did_documents│ │ ucan_delegations │ │ │
│ │ │ │ │ │ │ ucan_invocations │ │ │
│ │ │ │ │ │ │ ucan_revocations │ │ │
│ │ └────────────┘ └────────────┘ └─────────────────────┘ │ │
│ └──────────────────────────────────────────────────────────┘ │
│ │
└─────────────────────────────────────────────────────────────────┘
```
## Schema Changes
### 1. Replace `ucan_tokens` with `ucan_delegations`
```sql
-- DROP TABLE IF EXISTS ucan_tokens; -- Migration step
-- UCAN Delegations: v1.0.0-rc.1 delegation envelopes
CREATE TABLE IF NOT EXISTS ucan_delegations (
id INTEGER PRIMARY KEY,
did_id INTEGER NOT NULL REFERENCES did_documents(id) ON DELETE CASCADE,
-- Content Identifier (immutable, unique)
cid TEXT NOT NULL UNIQUE,
-- Sealed envelope (DAG-CBOR encoded)
envelope BLOB NOT NULL,
-- Extracted fields for indexing/queries
iss TEXT NOT NULL, -- Issuer DID
aud TEXT NOT NULL, -- Audience DID
sub TEXT, -- Subject DID (null = powerline)
cmd TEXT NOT NULL, -- Command (e.g., "/vault/read")
-- Policy stored as JSON for inspection (actual evaluation uses envelope)
pol TEXT DEFAULT '[]', -- Policy JSON
-- Temporal fields
nbf TEXT, -- Not before (ISO8601)
exp TEXT, -- Expiration (ISO8601, null = never)
-- Metadata
is_root INTEGER NOT NULL DEFAULT 0, -- iss == sub
is_powerline INTEGER NOT NULL DEFAULT 0, -- sub IS NULL
created_at TEXT NOT NULL DEFAULT (datetime('now'))
);
CREATE INDEX idx_ucan_delegations_cid ON ucan_delegations(cid);
CREATE INDEX idx_ucan_delegations_did_id ON ucan_delegations(did_id);
CREATE INDEX idx_ucan_delegations_iss ON ucan_delegations(iss);
CREATE INDEX idx_ucan_delegations_aud ON ucan_delegations(aud);
CREATE INDEX idx_ucan_delegations_sub ON ucan_delegations(sub);
CREATE INDEX idx_ucan_delegations_cmd ON ucan_delegations(cmd);
CREATE INDEX idx_ucan_delegations_exp ON ucan_delegations(exp);
```
### 2. Add `ucan_invocations` Table
```sql
-- UCAN Invocations: v1.0.0-rc.1 invocation envelopes (audit log)
CREATE TABLE IF NOT EXISTS ucan_invocations (
id INTEGER PRIMARY KEY,
did_id INTEGER NOT NULL REFERENCES did_documents(id) ON DELETE CASCADE,
-- Content Identifier
cid TEXT NOT NULL UNIQUE,
-- Sealed envelope (DAG-CBOR encoded)
envelope BLOB NOT NULL,
-- Extracted fields for indexing
iss TEXT NOT NULL, -- Invoker DID
sub TEXT NOT NULL, -- Subject DID
aud TEXT, -- Executor DID (if different from sub)
cmd TEXT NOT NULL, -- Command invoked
-- Proof chain (JSON array of delegation CIDs)
prf TEXT NOT NULL DEFAULT '[]',
-- Temporal
exp TEXT, -- Expiration
iat TEXT, -- Issued at
-- Execution tracking
executed_at TEXT, -- When actually executed
result_cid TEXT, -- CID of receipt (if executed)
created_at TEXT NOT NULL DEFAULT (datetime('now'))
);
CREATE INDEX idx_ucan_invocations_cid ON ucan_invocations(cid);
CREATE INDEX idx_ucan_invocations_iss ON ucan_invocations(iss);
CREATE INDEX idx_ucan_invocations_sub ON ucan_invocations(sub);
CREATE INDEX idx_ucan_invocations_cmd ON ucan_invocations(cmd);
```
### 3. Update `ucan_revocations` (Minor Changes)
```sql
-- UCAN Revocations: Track revoked delegations
-- (Mostly unchanged, but add invocation reference)
CREATE TABLE IF NOT EXISTS ucan_revocations (
id INTEGER PRIMARY KEY,
delegation_cid TEXT NOT NULL UNIQUE, -- CID of revoked delegation
revoked_by TEXT NOT NULL, -- Revoker DID
invocation_cid TEXT, -- CID of revocation invocation
reason TEXT,
revoked_at TEXT NOT NULL DEFAULT (datetime('now')),
FOREIGN KEY (delegation_cid) REFERENCES ucan_delegations(cid) ON DELETE CASCADE
);
CREATE INDEX idx_ucan_revocations_delegation_cid ON ucan_revocations(delegation_cid);
CREATE INDEX idx_ucan_revocations_revoked_by ON ucan_revocations(revoked_by);
```
### 4. Remove `delegations` Table
The old `delegations` table extracted fields from `ucan_tokens`. In v1.0.0-rc.1, the delegation IS the token. The `ucan_delegations` table replaces both.
```sql
-- DROP TABLE IF EXISTS delegations; -- Migration step
```
## Query Examples
### Get Delegation by CID (for go-ucan Loader)
```sql
-- name: GetDelegationByCID :one
SELECT envelope FROM ucan_delegations WHERE cid = ? LIMIT 1;
```
### List Delegations Granted TO a DID (audience)
```sql
-- name: ListDelegationsToAudience :many
SELECT * FROM ucan_delegations
WHERE aud = ? AND (exp IS NULL OR exp > datetime('now'))
ORDER BY created_at DESC;
```
### List Delegations Granted BY a DID (issuer)
```sql
-- name: ListDelegationsByIssuer :many
SELECT * FROM ucan_delegations
WHERE iss = ? AND (exp IS NULL OR exp > datetime('now'))
ORDER BY created_at DESC;
```
### Find Delegations for a Command
```sql
-- name: ListDelegationsForCommand :many
SELECT * FROM ucan_delegations
WHERE did_id = ?
AND (cmd = ? OR cmd = '/' OR ? LIKE cmd || '/%')
AND (exp IS NULL OR exp > datetime('now'))
ORDER BY created_at DESC;
```
### Check if Delegation is Revoked
```sql
-- name: IsDelegationRevoked :one
SELECT EXISTS(SELECT 1 FROM ucan_revocations WHERE delegation_cid = ?) as revoked;
```
## Go Integration
### Delegation Loader Implementation
```go
// internal/keybase/ucan_loader.go
package keybase
import (
"context"
"fmt"
"github.com/ipfs/go-cid"
"github.com/ucan-wg/go-ucan/token/delegation"
)
// DelegationLoader implements delegation.Loader for go-ucan
type DelegationLoader struct {
queries *Queries
}
func NewDelegationLoader(queries *Queries) *DelegationLoader {
return &DelegationLoader{queries: queries}
}
// GetDelegation implements delegation.Loader
func (l *DelegationLoader) GetDelegation(c cid.Cid) (*delegation.Token, error) {
ctx := context.Background()
envelope, err := l.queries.GetDelegationEnvelopeByCID(ctx, c.String())
if err != nil {
return nil, fmt.Errorf("delegation not found: %s", c)
}
// Decode DAG-CBOR envelope to delegation token
return delegation.FromSealed(envelope)
}
```
### Action Manager Integration
```go
// internal/keybase/actions_delegation_v2.go
type DelegationV2Result struct {
CID string `json:"cid"`
Issuer string `json:"iss"`
Audience string `json:"aud"`
Subject string `json:"sub,omitempty"`
Command string `json:"cmd"`
Policy string `json:"pol"`
ExpiresAt string `json:"exp,omitempty"`
IsRoot bool `json:"is_root"`
CreatedAt string `json:"created_at"`
}
func (am *ActionManager) StoreDelegation(ctx context.Context, sealed []byte, c cid.Cid) (*DelegationV2Result, error) {
// Decode to extract indexed fields
token, err := delegation.FromSealed(sealed)
if err != nil {
return nil, err
}
// Store in database
result, err := am.kb.queries.CreateDelegationV2(ctx, CreateDelegationV2Params{
DidID: am.kb.didID,
Cid: c.String(),
Envelope: sealed,
Iss: token.Issuer().String(),
Aud: token.Audience().String(),
Sub: didToNullable(token.Subject()),
Cmd: token.Command().String(),
Pol: policyToJSON(token.Policy()),
Exp: timeToNullable(token.Expiration()),
Nbf: timeToNullable(token.NotBefore()),
IsRoot: boolToInt(token.IsRoot()),
IsPowerline: boolToInt(token.IsPowerline()),
})
return delegationV2ToResult(result), nil
}
```
## Migration Path
1. **Create new tables** alongside old ones
2. **Migrate existing data** (if any JWT tokens exist)
- Parse old `raw_token`
- Re-encode as v1.0.0-rc.1 envelope (requires re-signing)
- Or: Mark old tokens as legacy, start fresh with v1.0.0-rc.1
3. **Update ActionManager** to use new tables
4. **Drop old tables** after migration verified
## Benefits
| Aspect | Old (JWT) | New (v1.0.0-rc.1) |
|--------|-----------|-------------------|
| Storage | JSON text | Binary CBOR (smaller) |
| Verification | Parse JWT, verify sig | go-ucan handles it |
| Proof Chain | JSON array in token | Separate CID references |
| Policy | `capabilities` JSON | Structured `pol` field |
| Interop | Non-standard | Spec-compliant |
## Conclusion
Integrating UCAN v1.0.0-rc.1 into the keybase schema:
1. **Maintains single-database portability** for WASM plugin
2. **Leverages existing infrastructure** (SQLC, ActionManager)
3. **Enables foreign key relationships** with DID documents
4. **Provides efficient queries** via indexed fields
5. **Supports go-ucan integration** via `delegation.Loader`