creds: rename "tpm2-absent" encryption to "null" encryption

This is what it is after all: encryption with a NULL key. This is more
descriptive, but also relevant since we want to use this kind of
credentials in a different context soon: for carrying pcrlock data into
a UKI. In that case we don#t want encryption, since the pcrlock data is
intended to help unlocking secrets, hence should not be a secret itself.

This only changes the code labels and the way this is labelled in the
output. We retain compat with the old name.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/creds/creds.c b/src/creds/creds.c
index 5586baff9a..f84eee292b 100644
--- a/src/creds/creds.c
+++ b/src/creds/creds.c
@@ -843,8 +843,8 @@ static int parse_argv(int argc, char *argv[]) {
                                 arg_with_key = CRED_AES256_GCM_BY_HOST_AND_TPM2_HMAC;
                         else if (STR_IN_SET(optarg, "host+tpm2-with-public-key", "tpm2-with-public-key+host"))
                                 arg_with_key = CRED_AES256_GCM_BY_HOST_AND_TPM2_HMAC_WITH_PK;
-                        else if (streq(optarg, "tpm2-absent"))
-                                arg_with_key = CRED_AES256_GCM_BY_TPM2_ABSENT;
+                        else if (STR_IN_SET(optarg, "null", "tpm2-absent"))
+                                arg_with_key = CRED_AES256_GCM_BY_NULL;
                         else
                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Unknown key type: %s", optarg);