Adjust secret key adding to consume instead of create

This changes `addKey` for secret storage to consume info about a pre-generated
key, rather than creating the key in middle of the method. This eases UI work
that want to have the public and private keys earlier on in the flow.

spec/unit/crypto/secrets.spec.js

@@ -284,7 +284,7 @@ describe("Secrets", function() {
 
     it("bootstraps when cross-signing keys in secret storage", async function() {
         const decryption = new global.Olm.PkDecryption();
-        decryption.generate_key();
+        const storagePublicKey = decryption.generate_key();
         const storagePrivateKey = decryption.get_private_key();
 
         let crossSigningKeys = {};
@@ -324,7 +324,7 @@ describe("Secrets", function() {
 
         // Set up cross-signing keys from scratch with specific storage key
         await bob.bootstrapSecretStorage({
-            createSecretStorageKey: async () => ({ privkey: storagePrivateKey }),
+            createSecretStorageKey: async () => ({ pubkey: storagePublicKey }),
         });
 
         // Clear local cross-signing keys and read from secret storage

src/client.js

@@ -1075,8 +1075,7 @@ MatrixClient.prototype.checkEventSenderTrust = async function(event) {
  * @function module:client~MatrixClient#addSecretStorageKey
  * @param {string} algorithm the algorithm used by the key
  * @param {object} opts the options for the algorithm.  The properties used
- *     depend on the algorithm given.  This object may be modified to pass
- *     information back about the key.
+ *     depend on the algorithm given.
  * @param {string} [keyName] the name of the key.  If not given, a random
  *     name will be generated.
  *

src/crypto/SecretStorage.js

@@ -18,8 +18,6 @@ import {EventEmitter} from 'events';
 import logger from '../logger';
 import olmlib from './olmlib';
 import { randomString } from '../randomstring';
-import { keyFromPassphrase } from './key_passphrase';
-import { encodeRecoveryKey } from './recoverykey';
 import { pkVerify } from './olmlib';
 
 export const SECRET_STORAGE_ALGORITHM_V1 = "m.secret_storage.v1.curve25519-aes-sha2";
@@ -71,8 +69,7 @@ export default class SecretStorage extends EventEmitter {
      *
      * @param {string} algorithm the algorithm used by the key.
      * @param {object} opts the options for the algorithm.  The properties used
-     *     depend on the algorithm given.  This object may be modified to pass
-     *     information back about the key.
+     *     depend on the algorithm given.
      * @param {string} [keyId] the ID of the key.  If not given, a random
      *     ID will be generated.
      *
@@ -92,21 +89,16 @@ export default class SecretStorage extends EventEmitter {
         {
             const decryption = new global.Olm.PkDecryption();
             try {
-                if (opts.passphrase) {
-                    const key = await keyFromPassphrase(opts.passphrase);
-                    keyData.passphrase = {
-                        algorithm: "m.pbkdf2",
-                        iterations: key.iterations,
-                        salt: key.salt,
-                    };
-                    opts.encodedkey = encodeRecoveryKey(key.key);
-                    keyData.pubkey = decryption.init_with_private_key(key.key);
-                } else if (opts.privkey) {
-                    keyData.pubkey = decryption.init_with_private_key(opts.privkey);
-                    opts.encodedkey = encodeRecoveryKey(opts.privkey);
+                const { passphrase, pubkey } = opts;
+                // Copies in public key details of the form generated by
+                // the Crypto module's `createRecoveryKeyFromPassphrase`.
+                if (passphrase && pubkey) {
+                    keyData.passphrase = passphrase;
+                    keyData.pubkey = pubkey;
+                } else if (pubkey) {
+                    keyData.pubkey = pubkey;
                 } else {
                     keyData.pubkey = decryption.generate_key();
-                    opts.encodedkey = encodeRecoveryKey(decryption.get_private_key());
                 }
             } finally {
                 decryption.free();

src/crypto/index.js

@@ -365,8 +365,7 @@ Crypto.prototype.createRecoveryKeyFromPassphrase = async function(password) {
  * called to await a secret storage key creation flow.
  * Returns:
  *     {Promise} A promise which resolves to key creation data for
- *     SecretStorage#addKey: an object with either `passphrase` or `privkey`
- *     fields.
+ *     SecretStorage#addKey: an object with `passphrase` and/or `pubkey` fields.
  */
 Crypto.prototype.bootstrapSecretStorage = async function({
     authUploadDeviceSigningKeys,