test failure cases

packages/common/src/repo/repo.ts

@@ -198,6 +198,19 @@ export class Repo {
     })
   }
 
+  async revert(count: number): Promise<void> {
+    let revertTo = this.cid
+    for (let i = 0; i < count; i++) {
+      const commit = await this.blockstore.get(revertTo, schema.commit)
+      const root = await this.blockstore.get(commit.root, schema.repoRoot)
+      if (root.prev === null) {
+        throw new Error(`Could not revert ${count} commits`)
+      }
+      revertTo = root.prev
+    }
+    await this.loadRoot(revertTo)
+  }
+
   // ROOT OPERATIONS
   // -----------
   async getCommit(): Promise<Commit> {

packages/common/tests/sync.test.ts

@@ -1,22 +1,24 @@
 import * as auth from '@adxp/auth'
-import { Repo } from '../src/repo'
+import { Repo, RepoRoot, TID } from '../src/repo'
 import { MemoryBlockstore } from '../src/blockstore'
 
 import * as util from './_util'
+import { AuthStore } from '@adxp/auth'
 
 describe('Sync', () => {
   let aliceBlockstore, bobBlockstore: MemoryBlockstore
   let aliceRepo: Repo
+  let aliceAuth: AuthStore
   let repoData: util.RepoData
 
   beforeAll(async () => {
     aliceBlockstore = new MemoryBlockstore()
-    const authStore = await auth.MemoryStore.load()
-    await authStore.claimFull()
+    aliceAuth = await auth.MemoryStore.load()
+    await aliceAuth.claimFull()
     aliceRepo = await Repo.create(
       aliceBlockstore,
-      await authStore.did(),
-      authStore,
+      await aliceAuth.did(),
+      aliceAuth,
     )
     bobBlockstore = new MemoryBlockstore()
   })
@@ -57,4 +59,56 @@ describe('Sync', () => {
     const diff = await bobRepo.loadAndVerifyDiff(diffCar)
     await util.checkRepo(bobRepo, repoData)
   })
+
+  it('throws an error on invalid UCANs', async () => {
+    const obj = util.generateObject()
+    const cid = await aliceBlockstore.put(obj)
+    const updatedData = await aliceRepo.data.add(`test/coll/${TID.next()}`, cid)
+    // we create an unrelated token for bob & try to permission alice's repo commit with it
+    const bobAuth = await auth.MemoryStore.load()
+    const badUcan = await bobAuth.claimFull()
+    const auth_token = await aliceBlockstore.put(auth.encodeUcan(badUcan))
+    const dataCid = await updatedData.save()
+    const root: RepoRoot = {
+      did: aliceRepo.did(),
+      prev: aliceRepo.cid,
+      auth_token,
+      data: dataCid,
+    }
+    const rootCid = await aliceBlockstore.put(root)
+    const commit = {
+      root: rootCid,
+      sig: await aliceAuth.sign(rootCid.bytes),
+    }
+    aliceRepo.cid = await aliceBlockstore.put(commit)
+    aliceRepo.data = updatedData
+    const diffCar = await aliceRepo.getDiffCar(bobRepo.cid)
+    await expect(bobRepo.loadAndVerifyDiff(diffCar)).rejects.toThrow()
+    await aliceRepo.revert(1)
+  })
+
+  it('throws on a bad signature', async () => {
+    const obj = util.generateObject()
+    const cid = await aliceBlockstore.put(obj)
+    const updatedData = await aliceRepo.data.add(`test/coll/${TID.next()}`, cid)
+    const auth_token = await aliceRepo.ucanForOperation(updatedData)
+    const dataCid = await updatedData.save()
+    const root: RepoRoot = {
+      did: aliceRepo.did(),
+      prev: aliceRepo.cid,
+      auth_token,
+      data: dataCid,
+    }
+    const rootCid = await aliceBlockstore.put(root)
+    // we generated a bad sig by signing the data cid instead of root cid
+    const commit = {
+      root: rootCid,
+      sig: await aliceAuth.sign(dataCid.bytes),
+    }
+    aliceRepo.cid = await aliceBlockstore.put(commit)
+    aliceRepo.data = updatedData
+    const diffCar = await aliceRepo.getDiffCar(bobRepo.cid)
+    await expect(bobRepo.loadAndVerifyDiff(diffCar)).rejects.toThrow()
+    await aliceRepo.revert(1)
+  })
 })