Add default value for potentially missing keyhash property in mod/salmon

diff --git a/mod/salmon.php b/mod/salmon.php
index ea5c334c0807a0460c54769fcee323b67035817c..bc4410434bbf362c14eee893fca773ade3bb0d70 100644 (file)
--- a/mod/salmon.php
+++ b/mod/salmon.php
@@ -79,7 +79,7 @@ function salmon_post(App $a, $xml = '') {
        // stash away some other stuff for later
 
        $type = $base->data[0]->attributes()->type[0];
-       $keyhash = $base->sig[0]->attributes()->keyhash[0];
+       $keyhash = $base->sig[0]->attributes()->keyhash[0] ?? '';
        $encoding = $base->encoding;
        $alg = $base->alg;