openpgp: Add a policy object.

  - Change all functions that need to evaluate the validity of a
    signature (either directly or indirectly to take a policy object.

  - Use the policy object to allow the user to place additional
    constraints on a signature's validity.

  - This addresses the first half of #274 (it introduces the policy
    object, but does not yet implement any policy).

1 files changed, 8 insertions, 5 deletions

diff --git a/openpgp/src/serialize/cert_armored.rs b/openpgp/src/serialize/cert_armored.rs
index 40c05464..fd312725 100644
--- a/openpgp/src/serialize/cert_armored.rs
+++ b/openpgp/src/serialize/cert_armored.rs
@@ -9,6 +9,7 @@ use crate::serialize::{
     Serialize, SerializeInto, generic_serialize_into, generic_export_into,
 };
 use crate::Cert;
+use crate::policy::StandardPolicy as P;
 
 
 /// Whether or not a character is printable.
@@ -23,23 +24,25 @@ impl Cert {
     /// Creates descriptive armor headers.
     ///
     /// Returns armor headers that describe this Cert.  The Cert's
-    /// primary fingerprint and userids are included as comments, so
-    /// that it is easier to identify the Cert when looking at the
-    /// armored data.
+    /// primary fingerprint and valid userids (according to the
+    /// default policy) are included as comments, so that it is easier
+    /// to identify the Cert when looking at the armored data.
     pub fn armor_headers(&self) -> Vec<String> {
+        let p = P::default();
+
         let length_value = armor::LINE_LENGTH - "Comment: ".len();
         // Create a header per userid.
         let mut headers: Vec<String> = self.userids().bindings()
             // Ignore revoked userids.
             .filter_map(|uidb| {
-                if let RevocationStatus::Revoked(_) = uidb.revoked(None) {
+                if let RevocationStatus::Revoked(_) = uidb.revoked(&p, None) {
                     None
                 } else {
                     Some(uidb)
                 }
             // Ignore userids not "alive".
             }).filter_map(|uidb| {
-                if uidb.binding_signature(None)?
+                if uidb.binding_signature(&p, None)?
                     .signature_alive(None, None).is_ok()
                 {
                     Some(uidb)