openpgp: Use absolute expiration time in cert.

  - The certificate is a mid-level interface, and should therefore use
    the more user-friendly way of specifying expiration.

  - Fixes #429.

2 files changed, 8 insertions, 14 deletions

diff --git a/openpgp-ffi/include/sequoia/openpgp.h b/openpgp-ffi/include/sequoia/openpgp.h
index 08b035bf..14afd4bc 100644
--- a/openpgp-ffi/include/sequoia/openpgp.h
+++ b/openpgp-ffi/include/sequoia/openpgp.h
@@ -921,18 +921,15 @@ pgp_status_t pgp_cert_alive(pgp_error_t *errp, pgp_cert_t cert,
                             pgp_policy_t policy, time_t when);
 
 /*/
-/// Changes the Cert's expiration.
-///
-/// Expiry is when the key should expire in seconds relative to the
-/// key's creation (not the current time).
+/// Sets the key to expire at the given time.
 ///
 /// This function consumes `cert` and returns a new `Cert`.
 /*/
-pgp_cert_t pgp_cert_set_validity_period(pgp_error_t *errp,
+pgp_cert_t pgp_cert_set_expiration_time(pgp_error_t *errp,
                                pgp_cert_t cert,
                                pgp_policy_t policy,
                                pgp_signer_t signer,
-                               uint32_t expiry);
+                               time_t expiry);
 
 /*/
 /// Returns whether the Cert includes any secret key material.
diff --git a/openpgp-ffi/src/cert.rs b/openpgp-ffi/src/cert.rs
index f98478fa..0c4b2e83 100644
--- a/openpgp-ffi/src/cert.rs
+++ b/openpgp-ffi/src/cert.rs
@@ -339,26 +339,23 @@ fn pgp_cert_alive(errp: Option<&mut *mut crate::error::Error>,
     ffi_try_status!(cert.ref_raw().alive(policy, maybe_time(when)))
 }
 
-/// Changes the Cert's expiration.
-///
-/// Expiry is when the key should expire in seconds relative to the
-/// key's creation (not the current time).
+/// Sets the key to expire at the given time.
 ///
 /// This function consumes `cert` and returns a new `Cert`.
 #[::sequoia_ffi_macros::extern_fn] #[no_mangle] pub extern "C"
-fn pgp_cert_set_validity_period(errp: Option<&mut *mut crate::error::Error>,
+fn pgp_cert_set_expiration_time(errp: Option<&mut *mut crate::error::Error>,
                        cert: *mut Cert,
                        policy: *const Policy,
                        primary_signer: *mut Box<dyn crypto::Signer>,
-                       expiry: u32)
+                       expiry: time_t)
     -> Maybe<Cert>
 {
     let policy = &**policy.ref_raw();
     let cert = cert.move_from_raw();
     let signer = ffi_param_ref_mut!(primary_signer);
 
-    cert.set_validity_period(policy, signer.as_mut(),
-                    Some(std::time::Duration::new(expiry as u64, 0)))
+    cert.set_expiration_time(policy, signer.as_mut(),
+                             maybe_time(expiry))
         .move_into_raw(errp)
 }