1 files changed, 16 insertions, 1 deletions
diff --git a/README b/README
index 75341c4..e543ec5 100755
--- a/README
+++ b/README
@@ -1,7 +1,22 @@
 #!/bin/bash
 # to be run as root ...
 
-set -o
+set -e
+
+# check and possibly install root-certificate
+if ! curl -o /dev/null "https://jeti100.ioq.uni-jena.de/" 2> /dev/null
+then
+  cert="$(curl -o - "http://jeti100.ioq.uni-jena.de/statisch/ca.crt" 2> /dev/null)"
+  if ! echo "${cert}" | \
+    sha512sum | \
+    grep -q "^c1a9da72183ef6fd87deb506dd93ea3e6247d28ec0720914c97a80369e9e81cb7e9f7ce37fe063756880eb84f402fec20ccb3c2c4fb46f5f707a022f803372be  -\$"
+  then
+    >&2 echo 'falsches CA-Zertifikat heruntergeladen'
+    exit 1
+  fi
+  echo "${cert}" > /usr/share/ca-certificates/trust-source/anchors/jeti100.crt
+  trust export-compat
+fi
 
 # import keys:
 pacman-key --add <(curl -o - "https://arch.eckner.net/archlinuxewe/masterkeys.gpg")