You can access the search result item from ~/Sitefinity/ControlTemplates/Search/SearchResult.ascx
repeater. Then you need to loop through each ResultItem, extract the item ID from the snippet and call CmsManager GetPage method where you pass the ID.
Finally call CheckDemand to see whether the currently logged in user have at least view permissions.
var cmsManager =
ICmsPage page = (ICmsPage)cmsManager.GetPage(pID);
PagePermission perm =
For IContent objects you have to work only with the provider. The current implementation does not expose permissions per ICotenent item.
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