GORM Scan / AfterFind hooks for every AES-encrypted column followed
the same lenient pattern:
if decrypted, err := utils.DecryptAESGCM(c.APIKey, key); err == nil {
c.APIKey = decrypted
}
When SYSTEM_AES_KEY was missing, rotated, or the wrong length the
decryption error was swallowed and the in-memory struct kept the raw
"enc:v1:..." ciphertext. The application then happily forwarded the
ciphertext upstream as the actual API key / password, surfacing as
401/403/SignatureDoesNotMatch from third-party vendors. Worse, a
ciphertext snippet of a customer credential was leaking into the
external provider's request logs.
Introduce utils.DecryptStoredSecret that:
- returns "" / legacy plaintext untouched (no false positives for
pre-encryption rows);
- returns ErrEncryptedDataMissingKey when the value carries the
enc:v1: prefix but no AES key is configured;
- propagates any GCM auth-tag failure from a rotated key.
Wire it into the five Scan / AfterFind sites that currently swallow
the error:
- Tenant.AfterFind (tenants.api_key)
- CredentialsConfig.Scan (tenants.we_knora_cloud.app_secret)
- ModelParameters.Scan (models.parameters.api_key, .app_secret)
- ConnectionConfig.Scan (vector_store_connections.password, .api_key)
- WebSearchProviderParameters.Scan (web_search_providers.api_key)
The error is wrapped with the originating column so the failure is
diagnosable in the logs. Operators must restore the previous
SYSTEM_AES_KEY (or rotate the affected secrets) instead of receiving
silent vendor 401s.
Add table-driven tests covering empty input, legacy plaintext,
round-trip, missing key, wrong-length key, and rotated key. The
strict path explicitly asserts that ciphertext does NOT leak in the
returned plaintext on any error path.
When a tenant setting is updated via PUT /tenants/kv/{key} (e.g.,
retrieval-config, parser-engine-config), the GORM AfterFind-decrypted
plaintext api_key was silently written back to the database because
db.Updates() does not trigger the BeforeSave hook.
Guard the repository's UpdateTenant to skip writing plaintext api_key
back to the database. Pre-encrypted values (enc:v1:… from CreateTenant
/ UpdateAPIKey) are written as-is; AfterFind-decrypted plaintext is
blanked so GORM skips the column entirely.
Closes#798
wizardchen