lib/gpg: Add _FINGERPRINT_PRIMARY to OstreeGpgVerifyResult

Revert the switch of _FINGERPRINT to giving the primary key ID
rather than the signing key ID, and instead add the primary
key ID as a new attribute which is available if the key is not
missing.

Closes: https://github.com/ostreedev/ostree/issues/608

Closes: #1092
Approved by: cgwalters

src/libostree/ostree-gpg-verify-result.c

@@ -63,7 +63,8 @@ static OstreeGpgSignatureAttr all_signature_attrs[] = {
   OSTREE_GPG_SIGNATURE_ATTR_PUBKEY_ALGO_NAME,
   OSTREE_GPG_SIGNATURE_ATTR_HASH_ALGO_NAME,
   OSTREE_GPG_SIGNATURE_ATTR_USER_NAME,
-  OSTREE_GPG_SIGNATURE_ATTR_USER_EMAIL
+  OSTREE_GPG_SIGNATURE_ATTR_USER_EMAIL,
+  OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT_PRIMARY
 };
 
 static void ostree_gpg_verify_result_initable_iface_init (GInitableIface *iface);
@@ -327,9 +328,9 @@ ostree_gpg_verify_result_get (OstreeGpgVerifyResult *result,
    * (OSTREE_GPG_SIGNATURE_ATTR_KEY_MISSING). */
   for (ii = 0; ii < n_attrs; ii++)
     {
-      if (attrs[ii] == OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT ||
+      if (attrs[ii] == OSTREE_GPG_SIGNATURE_ATTR_USER_NAME ||
-          attrs[ii] == OSTREE_GPG_SIGNATURE_ATTR_USER_NAME ||
+          attrs[ii] == OSTREE_GPG_SIGNATURE_ATTR_USER_EMAIL ||
-          attrs[ii] == OSTREE_GPG_SIGNATURE_ATTR_USER_EMAIL)
+          attrs[ii] == OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT_PRIMARY)
         {
           (void) gpgme_get_key (result->context, signature->fpr, &key, 0);
           break;
@@ -372,11 +373,7 @@ ostree_gpg_verify_result_get (OstreeGpgVerifyResult *result,
             break;
 
           case OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT:
-            if (key != NULL && key->subkeys != NULL)
+            child = g_variant_new_string (signature->fpr);
-              v_string = key->subkeys->fpr;
-            else
-              v_string = signature->fpr;
-            child = g_variant_new_string (v_string);
             break;
 
           case OSTREE_GPG_SIGNATURE_ATTR_TIMESTAMP:
@@ -417,6 +414,14 @@ ostree_gpg_verify_result_get (OstreeGpgVerifyResult *result,
             child = g_variant_new_string (v_string);
             break;
 
+          case OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT_PRIMARY:
+            if (key != NULL && key->subkeys != NULL)
+              v_string = key->subkeys->fpr;
+            if (v_string == NULL)
+              v_string = "";
+            child = g_variant_new_string (v_string);
+            break;
+
           default:
             g_critical ("Invalid signature attribute (%d)", attrs[ii]);
             g_variant_builder_clear (&builder);
@@ -534,6 +539,7 @@ ostree_gpg_verify_result_describe_variant (GVariant *variant,
   gint64 exp_timestamp;
   const char *type_string;
   const char *fingerprint;
+  const char *fingerprint_primary;
   const char *pubkey_algo;
   const char *user_name;
   const char *user_email;
@@ -549,7 +555,7 @@ ostree_gpg_verify_result_describe_variant (GVariant *variant,
   /* Verify the variant's type string.  This code is
    * not prepared to handle just any random GVariant. */
   type_string = g_variant_get_type_string (variant);
-  g_return_if_fail (strcmp (type_string, "(bbbbbsxxssss)") == 0);
+  g_return_if_fail (strcmp (type_string, "(bbbbbsxxsssss)") == 0);
 
   /* The default format roughly mimics the verify output generated by
    * check_sig_and_print() in gnupg/g10/mainproc.c, though obviously
@@ -563,6 +569,8 @@ ostree_gpg_verify_result_describe_variant (GVariant *variant,
                        "b", &key_missing);
   g_variant_get_child (variant, OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT,
                        "&s", &fingerprint);
+  g_variant_get_child (variant, OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT_PRIMARY,
+                       "&s", &fingerprint_primary);
   g_variant_get_child (variant, OSTREE_GPG_SIGNATURE_ATTR_TIMESTAMP,
                        "x", &timestamp);
   g_variant_get_child (variant, OSTREE_GPG_SIGNATURE_ATTR_EXP_TIMESTAMP,
@@ -627,6 +635,21 @@ ostree_gpg_verify_result_describe_variant (GVariant *variant,
                               user_name, user_email);
     }
 
+  if (!key_missing && (g_strcmp0 (fingerprint, fingerprint_primary) != 0))
+    {
+      const char *key_id_primary;
+
+      len = strlen (fingerprint_primary);
+      key_id_primary = (len > 16) ? fingerprint_primary + len - 16 :
+                                    fingerprint_primary;
+
+      if (line_prefix != NULL)
+        g_string_append (output_buffer, line_prefix);
+
+      g_string_append_printf (output_buffer,
+                              "Primary key ID %s\n", key_id_primary);
+    }
+
   if (exp_timestamp > 0)
     {
       date_time_utc = g_date_time_new_from_unix_utc (exp_timestamp);

src/libostree/ostree-gpg-verify-result.h

@@ -64,6 +64,11 @@ typedef struct OstreeGpgVerifyResult OstreeGpgVerifyResult;
  * @OSTREE_GPG_SIGNATURE_ATTR_USER_EMAIL:
  *   [#G_VARIANT_TYPE_STRING] The email address of the signing key's primary
  *   user
+ * @OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT_PRIMARY:
+ *   [#G_VARIANT_TYPE_STRING] Fingerprint of the signing key's primary key
+ *   (will be the same as OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT if the
+ *   the signature is already from the primary key rather than a subkey,
+ *   and will be the empty string if the key is missing.)
  *
  * Signature attributes available from an #OstreeGpgVerifyResult.
  * The attribute's #GVariantType is shown in brackets.
@@ -80,7 +85,8 @@ typedef enum {
   OSTREE_GPG_SIGNATURE_ATTR_PUBKEY_ALGO_NAME,
   OSTREE_GPG_SIGNATURE_ATTR_HASH_ALGO_NAME,
   OSTREE_GPG_SIGNATURE_ATTR_USER_NAME,
-  OSTREE_GPG_SIGNATURE_ATTR_USER_EMAIL
+  OSTREE_GPG_SIGNATURE_ATTR_USER_EMAIL,
+  OSTREE_GPG_SIGNATURE_ATTR_FINGERPRINT_PRIMARY,
 } OstreeGpgSignatureAttr;
 
 _OSTREE_PUBLIC

tests/test-gpg-verify-result.c

@@ -173,7 +173,7 @@ test_attribute_basics (TestFixture *fixture,
       tuple = ostree_gpg_verify_result_get_all (fixture->result, ii);
 
       type_string = g_variant_get_type_string (tuple);
-      g_assert_cmpstr (type_string, ==, "(bbbbbsxxssss)");
+      g_assert_cmpstr (type_string, ==, "(bbbbbsxxsssss)");
 
       /* Check attributes which should be common to all signatures. */