auto retrieve keys from PKA. Thsi allows to specify an email address

so that gpg can get the key from DNS.  This helps with opportunistic
encryption.  No integration with the trust modell yet.

1 files changed, 48 insertions, 12 deletions

diff --git a/g10/getkey.c b/g10/getkey.c
index 7991b81af..59f18f6a5 100644
--- a/g10/getkey.c
+++ b/g10/getkey.c
@@ -35,6 +35,7 @@
 #include "main.h"
 #include "trustdb.h"
 #include "i18n.h"
+#include "keyserver-internal.h"
 
 #define MAX_PK_CACHE_ENTRIES   PK_UID_CACHE_SIZE
 #define MAX_UID_CACHE_ENTRIES  PK_UID_CACHE_SIZE
@@ -886,24 +887,59 @@ key_byname( GETKEY_CTX *retctx, STRLIST namelist,
     return rc;
 }
 
-/*
- * Find a public key from NAME and returh the keyblock or the key.
- * If ret_kdb is not NULL, the KEYDB handle used to locate this keyblock is
- * returned and the caller is responsible for closing it.
- */
+
+
+/* Find a public key from NAME and return the keyblock or the key.  If
+   ret_kdb is not NULL, the KEYDB handle used to locate this keyblock
+   is returned and the caller is responsible for closing it.  If a key
+   was not found and NAME is a valid RFC822 mailbox and PKA retrieval
+   has been enabled, we try to import the pkea via the PKA
+   mechanism. */
 int
 get_pubkey_byname (PKT_public_key *pk,
 		   const char *name, KBNODE *ret_keyblock,
                    KEYDB_HANDLE *ret_kdbhd, int include_unusable )
 {
-    int rc;
-    STRLIST namelist = NULL;
+  int rc;
+  int again = 0;
+  STRLIST namelist = NULL;
 
-    add_to_strlist( &namelist, name );
-    rc = key_byname( NULL, namelist, pk, NULL, 0,
-		     include_unusable, ret_keyblock, ret_kdbhd);
-    free_strlist( namelist );
-    return rc;
+  add_to_strlist( &namelist, name );
+ retry:
+  rc = key_byname( NULL, namelist, pk, NULL, 0,
+                   include_unusable, ret_keyblock, ret_kdbhd);
+  if (rc == G10ERR_NO_PUBKEY
+      && !again
+      && (opt.keyserver_options.options&KEYSERVER_AUTO_PKA_RETRIEVE)
+      && is_valid_mailbox (name))
+    {
+      /* If the requested name resembles a valid mailbox and
+         automatic retrieval via PKA records has been enabled, we
+         try to import the key via the URI and try again. */
+      unsigned char fpr[MAX_FINGERPRINT_LEN];
+      char *uri;
+      struct keyserver_spec *spec;
+      
+      uri = get_pka_info (name, fpr);
+      if (uri)
+        {
+          spec = parse_keyserver_uri (uri, 0, NULL, 0);
+          if (spec)
+            {
+              glo_ctrl.in_auto_key_retrieve++;
+              if (!keyserver_import_fprint (fpr, 20, spec))
+                again = 1;
+              glo_ctrl.in_auto_key_retrieve--;
+              free_keyserver_spec (spec);
+            }
+          xfree (uri);
+        }
+      if (again)
+        goto retry;
+    }
+
+  free_strlist( namelist );
+  return rc;
 }
 
 int