acra-backup (deprecated since 0.96.0) #

acra-backup is a command-line utility used for storing and managing the keystore backups.

acra-backup is deprecated since 0.96.0 and will be removed in 0.97.0. Please, use acra-keys instead.

Command line flags #

General #

--action={import|export}🔴

Actions to perform.

Logging #

--logging_format={plaintext|json|CEF}

Logging format. Default is plaintext.

plaintext — (default) pretty human readable key/value format

INFO[2021-09-16T09:58:03+03:00] Starting service acra-backup [pid=459748]     version=0.85.0

json — one JSON object per line, easy to parse by most log collectors

{"level":"info","msg":"Starting service acra-backup [pid=460911]","product":"acra-backup","timestamp":"2021-09-16T10:14:33+03:00","unixTime":"1631776473.899","version":"0.85.0"}

CEF — Common Event Format

CEF:0|cossacklabs|acra-backup|0.85.0|100|Starting service acra-backup [pid\=461095]|1|unixTime=1631776510.183

TLS (available since 0.96.0) #

--tls_auth=<mode>

Set authentication mode that will be used for TLS connection.
- 0 — do not request client certificate, ignore it if received;
- 1 — request client certificate, but don’t require it;
- 2 — expect to receive at least one certificate to continue the handshake;
- 3 — don’t require client certificate, but validate it if client actually sent it;
- 4 — (default) request and validate client certificate.
These values correspond to crypto.tls.ClientAuthType.
--tls_key=<filename>

Path to acra-backup TLS certificate’s private key of the TLS certificate presented to Database (acra-backup works as “client” when communicating with Database). Empty by default.
--tls_cert=<filename>

Path to acra-backup TLS certificate presented to Database (acra-backup works as “client” when communicating with Database). Empty by default.
--tls_ca=<filename>

Path to acra-backup TLS certificate’s CA certificate for Database certificate validation (acra-backup works as “client” when communicating with Database). Empty by default.
--tls_crl_url=<url>

URL of the Certificate Revocation List (CRL) to use. Empty by default.

Can be either http:// or file:// (for local files). When using local file, Acra will simply read the file and won’t monitor filesystem for changes afterwards. Usual caching rules apply (see --tls_crl_cache_time).
--tls_crl_from_cert=<policy>

How to treat CRL’s URL described in a certificate itself
- use — try URL(s) from certificate after the one from configuration (if set)
- trust — try first URL from certificate, if it does not contain checked certificate, stop further checks
- prefer — (default) try URL(s) from certificate before the one from configuration (if set)
- ignore — completely ignore CRL’s URL(s) specified in certificate
--tls_crl_cache_size=<count>

How many CRLs to cache in memory. Use 0 to disable caching. Maximum is 1000000. Default is 16. Cache uses LRU policy.
--tls_crl_cache_time=<seconds>

How long to keep CRLs cached, in seconds. Use 0 to disable caching. Maximum is 300 seconds. Default is 0.
--tls_crl_check_only_leaf_certificate={true|false}

This flag controls behavior of validator in cases when certificate chain contains at least one intermediate certificate.
- true — validate only leaf certificate
- false — (default) validate leaf certificate and all intermediate certificates
This option may be enabled in cases when intermediate CAs are trusted and there is no need to verify them all the time. Also, even if this flag is false but there is no CRL’s URL configured and there is no CRL’s URL in intermediate CA certificates, these intermediate CAs won’t be validated since we don’t know which CRLs could be used for validation.
--tls_ocsp_required=<policy>

How to handle situation when OCSP server doesn’t know about requested certificate and returns “Unknown”.
- denyUnknown — (default) consider “Unknown” response an error, certificate will be rejected
- allowUnknown — reverse of denyUnknown, allow certificates unknown to OCSP server
- requireGood — require all known OCSP servers to respond “Good” in order to allow certificate and continue TLS handshake, this includes all URLs validator can use, from certificate (if not ignored) and from configuration
--tls_ocsp_url=<url>

URL of OCSP service. Empty by default.

Should point to HTTP server that accepts application/ocsp-request MIME type and responds with application/ocsp-response.
--tls_ocsp_from_cert=<policy>

How to treat OCSP server URL described in a certificate itself.
- use — try URL(s) from certificate after the one from configuration (if set)
- trust — try URL(s) from certificate, if server returns “Valid”, stop further checks
- prefer — (default) try URL(s) from certificate before the one from configuration (if set)
- ignore — completely ignore OCSP’s URL(s) specified in certificate
--tls_ocsp_check_only_leaf_certificate={true|false}

This flag controls behavior of validator in cases when certificate chain contains at least one intermediate certificate.
- true — validate only leaf certificate
- false — (default) validate leaf certificate and all intermediate certificates
This option may be enabled in cases when intermediate CAs are trusted and there is no need to verify them all the time. Also, even if this flag is false but there is no OCSP’s URL configured and there is no OCSP’s URL in intermediate CA certificates, these intermediate CAs won’t be validated since we don’t know whom to ask about them.

Storage destination #

Filesystem #

--keys_private_dir=<dir_path>

Folder with private keys. Default is .acrakeys.
--keys_public_dir=<dir_path>

Folder with public keys. Leave empty if keys stored in same folder as keys_private_dir.
--file=<path>🔴

Path to file which will be used for import|export actions. Required to specify.

Redis #

--redis_db_keys=<number>

Redis database number to use. Default is 0.
--redis_host_port=<host:port>

Address of Redis database to use as keystore. If not specified, Redis is not used.
--redis_password=<password>

Password to Redis database.

Keystore #

--keystore_encryption_type=<strategy>

Keystore encryption strategy. Currently supported strategies:
- env_master_key (Default) - Keystore using Acra Master Key, loaded from ENV (ACRA_MASTER_KEY) variable;
- vault_master_key - Keystore using Acra Master Key, loaded from Hashicorp Vault
- kms_encrypted_master_key - Keystore using Acra Master Key, loaded from ENV ACRA_MASTER_KEY variable and decrypted via KMS key-encryption key.
- kms_per_client - Keystore using KMS for decryption Acra keys per ClientID and ZoneID (zones are deprecated since 0.94.0, will be removed in 0.95.0).

KMS #

--kms_type=<type>

Specify your KMS. Currently supported KMS types:
- aws - AWS Key Management Service
--kms_credentials_path=<filepath>

A path to a file with KMS credentials JSON format.

Example of KMS config:

AWS:

   {"access_key_id":"<access_key_id>","secret_access_key":"<secret_access_key>","region":"<region>"}

Note: Should be provided only with --keystore_encryption_type=<kms_encrypted_master_key|kms_per_client> flags.

Hashicorp Vault #

--vault_connection_api_string=<url>

Connection string (like http://x.x.x.x:yyyy) for loading ACRA_MASTER_KEY from HashiCorp Vault. Default is empty (ACRA_MASTER_KEY environment variable is expected).
--vault_secrets_path=<path>

KV Secret Path for reading ACRA_MASTER_KEY from HashiCorp Vault. Default is secret/.
--vault_tls_transport_enable=<true|false>

Turns on/off TLS for connection with vault to --vault_connection_api_string endpoint.
- true — turns on
- false — (default) turns off.
--vault_tls_client_auth=<mode>

Set authentication mode that will be used for TLS connection with Vault.
- 0 — do not request client certificate, ignore it if received;
- 1 — request client certificate, but don’t require it;
- 2 — expect to receive at least one certificate to continue the handshake;
- 3 — don’t require client certificate, but validate it if client actually sent it;
- 4 — (default) request and validate client certificate.
These values correspond to crypto.tls.ClientAuthType. If not specified, acra-backup uses value from --tls_auth flag.
--vault_tls_ca_path=<filename>

Path to CA certificate for HashiCorp Vault certificate validation. Default is empty (deprecated since 0.94.0, use vault_tls_client_ca instead).
--vault_tls_client_ca=<filename>

Path to acra-backup TLS certificate’s CA certificate for Vault certificate validation (acra-backup works as “client” when communicating with Vault). Empty by default. If not specified, acra-backup uses value from --tls_ca flag. (since 0.96.0)
--vault_tls_client_cert=<filename>

Path to acra-backup TLS certificate presented to Vault (acra-backup works as “client” when communicating with Vault). Empty by default. If not specified, acra-backup uses value from --tls_cert flag. (since 0.96.0)
--vault_tls_client_key=<filename>

Path to acra-backup TLS certificate’s private key of the TLS certificate presented to Vault (acra-backup works as “client” when communicating with Vault). Empty by default. If not specified, acra-backup uses value from --tls_key flag. (since 0.96.0)
--vault_tls_client_sni=<SNI>

Expected Server Name (SNI) of the Vault instance. Will be used --vault_connection_api_string value if is empty. Empty by default.
--vault_tls_crl_client_cache_size=<count>

How many CRLs to cache in memory in connections to Vault. Use 0 to disable caching. Maximum is 1000000. Default is 16. Cache uses LRU policy. If not specified, acra-backup uses value from --tls_crl_cache_size flag. (since 0.96.0)
--vault_tls_crl_client_cache_time=<seconds>

How long to keep CRLs cached, in seconds for connections to Vault. Use 0 to disable caching. Maximum is 300 seconds. Default is 0. If not specified, acra-backup uses value from --tls_crl_cache_time flag. (since 0.96.0)
--vault_tls_crl_client_check_only_leaf_certificate={true|false}

This flag controls behavior of validator in cases when Vault certificate chain contains at least one intermediate certificate.
- true — validate only leaf certificate
- false — (default) validate leaf certificate and all intermediate certificates
This option may be enabled in cases when intermediate CAs are trusted and there is no need to verify them all the time. Also, even if this flag is false but there is no CRL’s URL configured and there is no CRL’s URL in intermediate CA certificates, these intermediate CAs won’t be validated since we don’t know which CRLs could be used for validation. If not specified, acra-backup uses value from --tls_crl_check_only_leaf_certificate flag. (since 0.96.0)
--vault_tls_crl_client_from_cert=<policy>

How to treat CRL’s URL described in a certificate from Vault server/agent
- use — try URL(s) from certificate after the one from configuration (if set)
- trust — try first URL from certificate, if it does not contain checked certificate, stop further checks
- prefer — (default) try URL(s) from certificate before the one from configuration (if set)
- ignore — completely ignore CRL’s URL(s) specified in certificate
“URL from configuration” above means the one configured with --vault_tls_crl_client_url flags. If not specified, acra-backup uses value from --tls_crl_from_cert flag. (since 0.96.0)
--vault_tls_crl_client_url=<url>

CRL’s URL for outcoming TLS connections to Vault. Empty by default. If not specified, acra-backup uses value from --tls_crl_url flag. (since 0.96.0)
--vault_tls_ocsp_client_check_only_leaf_certificate={true|false}

This flag controls behavior of validator in cases when Vault certificate chain contains at least one intermediate certificate.
- true — validate only leaf certificate
- false — (default) validate leaf certificate and all intermediate certificates
This option may be enabled in cases when intermediate CAs are trusted and there is no need to verify them all the time. Also, even if this flag is false but there is no OCSP’s URL configured and there is no OCSP’s URL in intermediate CA certificates, these intermediate CAs won’t be validated since we don’t know whom to ask about them. If not specified, acra-backup uses value from --tls_ocsp_check_only_leaf_certificate flag. (since 0.96.0)
--vault_tls_ocsp_client_from_cert=<policy>

How to treat OCSP server URL described in a certificate from Vault server.
- use — try URL(s) from certificate after the one from configuration (if set)
- trust — try URL(s) from certificate, if server returns “Valid”, stop further checks
- prefer — (default) try URL(s) from certificate before the one from configuration (if set)
- ignore — completely ignore OCSP’s URL(s) specified in certificate
“URL from configuration” above means the one configured with --vault_tls_ocsp_client_url flags. If not specified, acra-backup uses value from --tls_ocsp_from_cert flag. (since 0.96.0)
--vault_tls_ocsp_client_required=<policy>

How to handle situation when OCSP server doesn’t know about requested Vault certificate and returns “Unknown”.
- denyUnknown — (default) consider “Unknown” response an error, certificate will be rejected
- allowUnknown — reverse of denyUnknown, allow certificates unknown to OCSP server
- requireGood — require all known OCSP servers to respond “Good” in order to allow certificate and continue TLS handshake, this includes all URLs validator can use, from certificate (if not ignored) and from configuration If not specified, acra-backup uses value from --tls_ocsp_required flag. (since 0.96.0)
--vault_tls_ocsp_client_url=<url>

OCSP service URL for outgoing TLS connections to check Vaults' certificates. Empty by default. If not specified, acra-backup uses value from --tls_ocsp_url flag.

Note: Should be provided only with --keystore_encryption_type=<vault_master_key> flag.

🔴 - flags required to be specified.

Usage example #

Using acra-backup you can easily migrate keys from different storages. Consider an example of migrating keys from a filesystem to Redis-based keystore. First, we need to export keys to file using export action:

$ acra-backup --action=export --file=./acrakeys.backup
INFO[2021-09-16T11:14:18+03:00] Starting service acra-backup [pid=470120]     version=0.85.0
INFO[2021-09-16T11:14:18+03:00] Initializing ACRA_MASTER_KEY loader...       
INFO[2021-09-16T11:14:18+03:00] Initialized default env ACRA_MASTER_KEY loader 
INFO[2021-09-16T11:14:18+03:00] Backup master key: 1FEbOQ1k2jzn2LsF5xHy7jQmT93Yv1odqqgg1epwUcQ=
 Backup saved to file: ./acrakeys.backup

Note: You need to have ACRA_MASTER_KEY environment variable set up for any operation using acra-backup.

Before running import operation, make sure you also specified BACKUP_MASTER_KEY environment variable with the value displayed in export operation output.

Then, we need to import keys using import action provided along with redis configuration flags:

$ export BACKUP_MASTER_KEY='1FEbOQ1k2jzn2LsF5xHy7jQmT93Yv1odqqgg1epwUcQ='
$ acra-backup \
    --action=import \
    --file=.acrakeys.backup \
    --redis_host_port=localhost:6379 \
    --redis_db_keys=0
INFO[2021-09-17T09:34:04+03:00] Starting service acra-backup [pid=488411]     version=0.85.0
INFO[2021-09-17T09:34:04+03:00] Initializing ACRA_MASTER_KEY loader...       
INFO[2021-09-17T09:34:04+03:00] Initialized default env ACRA_MASTER_KEY loader

To make sure that all keys were successfully migrated to redis you can run:

$ redis-cli --scan --pattern '*'
".acrakeys/user0_storage.pub"
".acrakeys/user0_storage"
".acrakeys/secure_log_key"
".acrakeys/DDDDDDDDYXtLNuuzjCXVeODJ_zone"
".acrakeys/user0.pub"
".acrakeys/user0_server.pub"
".acrakeys/DDDDDDDDYXtLNuuzjCXVeODJ_zone_sym"
".acrakeys/user0_hmac"
".acrakeys/user0_translator"
".acrakeys/user0"
".acrakeys/user0_translator.pub"
".acrakeys/DDDDDDDDYXtLNuuzjCXVeODJ_zone.pub"
".acrakeys/user0_storage_sym"
".acrakeys/auth_key"
".acrakeys/user0_server"