Assertions
| Input | API | Purpose |
|---|---|---|
| RP ID |
fido_assert_set_rp()
|
Bind the assertion to the RP. |
| Challenge binding |
fido_assert_set_clientdata_hash()
|
Set the current client-data hash; the challenge must be fresh. |
| Allowed credentials |
fido_assert_allow_cred()
|
Restrict the device to known credential IDs. |
| Presence / verification |
fido_assert_set_up()
/
fido_assert_set_uv()
|
Control requested user interaction. |
Allocate with
fido_assert_new()[library], set request fields, then call
fido_dev_get_assert(). Read the number of returned statements with
fido_assert_count(); the first statement has index 0.
Assertion generation does not perform local verification. For verification,
fido_assert_verify()[WebAuthn]
checks a statement against the stored public key and COSE algorithm. The application still
controls challenge freshness, account lookup, and replay handling.