pvapconfig - Man Page

automatic configure APQNs within an SE KVM guest.

Synopsis

pvapconfig [Options]

Description

pvapconfig is a tool for automatically configuring the APQNs within an Secure Execution KVM guest with AP pass-through support. Based on a given AP configuration it tries to find matching APQNs and binds and associates them with the given secret(s).

Here is a description of pvapconfig's process:

1. Check AP bus: Support for AP bus needs to be available and the AP

bus needs to support APSB. APSB is only available within an KVM SE guest with AP pass-through support.

2. Check Ultravisor: UV support needs to be available and the UV needs

to support the list secrets feature.

3. Read in and validate the AP configuration file. By default if not

overwritten by the --config option the AP configuration is read from /etc/pvapconfig.yaml and syntactically verified. See section Configfile for details about the syntax and semantic of the configuration file.

4. Fetch the list of association secrets from the UV. Actually the

index of the secret and the secret id for each entry is collected. The secret value is NOT fetched as it is NOT accessible but only usable within the UV firmware.

5. Gather all APQNs available within this KVM SE guest. Collect

information about each APQN like online states, crypto card serial numbers and master key verification patterns (MKVP).

6. Go through all AP config entries. For each AP config entry try to

find an APQN which is already configured (bound/associated) to satisfy this config entry. If such a match is found, the AP config entry is assumed to be fulfilled and marked as done.

7. All remaining APQNs which do not already satisfy an AP config entry

are now examined for their bind and association state and maybe reset to unbound state.

8. Go through all AP config entries which are still not

fulfilled. For each such AP config entry try to search for an APQN which would match to this entry and then prepare this APQN (bind, maybe associate). If successful, mark the AP config entry as done.

9. Evaluation of the applied AP config entries. Applied means the AP

config entry has been fulfilled either in step 6 or in step 8. With the strict option given ALL AP config entries need to apply otherwise an error message is printed and pvapconfig returns with exit failure. If the strict option is not given, it is enough to satisfy at least one AP config entry from the configuration and pvapconfig will return successfully.

Options

-c,  --config <configfile>

Use <configfile> as the AP config file for pvapconfig. If pvapconfig is run without this option the default configuration file /etc/pvapconfig.yaml is used.

-h,  --help

Print pvapconfig usage information and exit.

-n,  --dry-run

Do not bind, unbind or associate APQNs but only process the configuration and the available APQNs and secrets and simulate the bind, unbind or associate action on the chosen APQN. Use it together with the verbose option to see which actions pvapconfig would do if unleashed.

-s,  --strict

All AP config entries need to be satisfied to have pvapconfig terminate with success. Without this option one applied AP config entry is enough to meet the expectations.

-v,  --verbose

Print out informational messages about what pvapconfig is actually doing.

-V,  --version

Print version information and exit.

Configfile

The pvapconfig yaml configuration file consists of a list of AP config entries. Each entry may hold this information:

- mode: AP queue mode information, required, either "EP11" or "Accel".
- mkvp: AP queue Master Key Verification Pattern (MKVP), required for

EP11, hex string optional prepented with 0x. The MKVP hex string value may hold either 16 bytes (32 hex characters) or 32 bytes (64 hex characters) but only the leftmost 16 bytes hold MKVP information and thus the rest is ignored.

- serialnr: Crypto Card Serial Number, string, optional for EP11,

ignored for Accel. As this is a real ASCII string uppercase and lowercase character(s) count different.

- mingen: Card Minimal Generation, string "CEX4", "CEX5", "CEX6",

"CEX7" or "CEX8" for Accelerator, string "CEC8" for EP11, optional. If given specifies the minimal accepted Crypto card generation.

- secretid: Secret id, hex string with optional 0x prepented, required

for EP11, ignored for Accel. Details see the following text.

- name: ASCII string, optional, but see details below.
- description: Description of this AP config entry, string, ignored,

 just for convenience for the reader or editor of the configuration.

The secret id uniquely identifies an association secret. However, it is a clumsy hex string of 64 characters which represent the readable sha256 value over the secret's name. So pvapconfig can use the name instead and calculate the secret id from the name. So the rule is:

- If name and secretid is given, the secretid needs to match to the

sha256 hash over the given name for this AP config entry.

- If only name is given then the secretid is calculated with a sha256

 hash over the given name.

- If only the secretid is given, there is nothing more to do but

verify that the value is a hex string with 64 characters.

Locking

Pvapconfig needs to have a consistent view of the AP resources during lifetime. There must not run multiple instances of pvapconfig or any manipulations of the AP resources in parallel. To prevent the execution of multiple pvapconfig instances the lock file /run/lock/pvapconfig.lock is established. A second instance of pvapconfig will detect this lock file and terminated with an error message. If for any reason this file still exists as a leftover from a previous pvapconfig crash for example, it needs to get removed by hand. The lock file contains the process id of the pvapconfig process which created this file.

Return Value

0 - Successful termination.

At least one AP config entry has been applied or at least one APQN has been found in a state matching to one AP config entry. If strict option is given, ALL AP config entries have been applied. An AP config entry is applied either by configuring the APQN accordingly or an APQN has been found which already fulfills the constrains.

1 - Failure.

Either some kind of failure happened during processing the configuration or the configuration could not get applied successful. In all cases pvapconfig prints out a message to standard error with details about the failure. Also pvapconfig does NOT reset the APQNs to the state found at the startup when failing to apply the configuration.

Notes

For more information and details see the IBM documentation about Confidential Computing "Introducing IBM Secure Execution for Linux" available at https://www.ibm.com/docs/.

See Also

pvsecret(1), lszcrypt(8), chzcrypt(8)

Info

DEC 2023 s390-tools