[FIXED] Restore of encrypted filestore with no main key could cause dataloss

[derekcollison]

When restoring a filestore with no key generator but it was encrypted, fail to restore.

Signed-off-by: Derek Collison derek@nats.io

[neilalexander]

In principle LGTM, but I wanted to be sure why this works, so I enabled server logging on the new TestJetStreamClusterBadEncryptKey.

What happens is that EnableJetStream() skips over all of the streams that it cannot decrypt and continues to start up. It's actually the setupMetaGroup() call that returns an error on creating the file store for the _meta_ group:

=== RUN   TestJetStreamClusterBadEncryptKey
[INF] Starting nats-server
[INF]   Version:  2.9.20-beta
[INF]   Git:      [not set]
[INF]   Cluster:  JSC
[INF]   Name:     S-3
[INF]   Node:     Z2sYEJH3
[INF]   ID:       NCRLBZHG3ZXJN5O74BXUMIWIDALGYMIXILHIRNFI6RPBNKYUXU4RBM7Y
[WRN] Plaintext passwords detected, use nkeys or bcrypt
[INF] Using configuration file: /var/folders/l7/w_j8hk_d59l_nw0hknw3c2q40000gn/T/TestJetStreamClusterBadEncryptKey2097575401/006/739122146
[INF] Starting JetStream
[INF]     _ ___ _____ ___ _____ ___ ___   _   __  __
[INF]  _ | | __|_   _/ __|_   _| _ \ __| /_\ |  \/  |
[INF] | || | _|  | | \__ \ | | |   / _| / _ \| |\/| |
[INF]  \__/|___| |_| |___/ |_| |_|_\___/_/ \_\_|  |_|
[INF] 
[INF]          https://docs.nats.io/jetstream
[INF] 
[INF] ---------------- JETSTREAM ----------------
[INF]   Max Memory:      256.00 MB
[INF]   Max Storage:     2.00 GB
[INF]   Store Directory: "/var/folders/l7/w_j8hk_d59l_nw0hknw3c2q40000gn/T/TestJetStreamClusterBadEncryptKey2097575401/005/jetstream"
[INF] -------------------------------------------
[WRN]   Error decrypting our stream metafile: encryption not enabled
[WRN]   Error decrypting our stream metafile: encryption not enabled
[WRN]   Error decrypting our stream metafile: encryption not enabled
[WRN]   Error decrypting our stream metafile: encryption not enabled
[WRN]   Error decrypting our stream metafile: encryption not enabled
[WRN]   Error decrypting our stream metafile: encryption not enabled
[WRN]   Error decrypting our stream metafile: encryption not enabled
[WRN]   Error decrypting our stream metafile: encryption not enabled
[WRN]   Error decrypting our stream metafile: encryption not enabled
[WRN]   Error decrypting our stream metafile: encryption not enabled
[INF] Starting JetStream cluster
[INF] Creating JetStream metadata controller
/var/folders/l7/w_j8hk_d59l_nw0hknw3c2q40000gn/T/TestJetStreamClusterBadEncryptKey2097575401/005/jetstream/$SYS/_js_/_meta_/meta.key
[ERR] Error creating filestore: encrypted store encountered with no main key
[FTL] Can't start JetStream: encrypted store encountered with no main key
FAIL    github.com/nats-io/nats-server/v2/server        4.246s

... which is fine for clustered mode as we can't skip creating _meta_, but we don't call setupMetaGroup() when running in standalone mode. That probably means that this fix won't do anything for standalone JetStream servers where we'll end up continuing startup without any streams loaded.

[derekcollison]

Will make logs more descriptive at the very least I think.

Do you think we should bail if a stream fails?

[neilalexander]

LGTM for now, will add a backlog item to revisit in 2.10.