Add crx build file

scripts/build-crx.sh

@@ -0,0 +1,42 @@
+#!/bin/bash -e
+#
+# Purpose: Pack a Chromium extension directory into crx format
+# gotten from: https://web.archive.org/web/20180114090616/https://developer.chrome.com/extensions/crx#scripts
+#
+# Script assumes we're in basedir of the repository and that extension has been built and zipped to /dist-zip
+# using the crx name we want (same name as zip, except different extension)
+# 
+# also this doesn't check for errors ever so
+#
+
+echo "entering dist-zip"
+cd ./dist-zip
+
+zip=`ls | grep chrome.zip`
+name="${name%.*}"
+crx="$name.crx"
+key="../keys/chrome-nightly.pub"
+pub="$name.pub"
+sig="$name.sig"
+trap 'rm -f "$pub" "$sig" "$zip"' EXIT
+
+# signature
+openssl sha1 -sha1 -binary -sign "$key" < "$zip" > "$sig"
+
+# public key
+openssl rsa -pubout -outform DER < "$key" > "$pub" 2>/dev/null
+
+byte_swap () {
+  # Take "abcdefgh" and return it as "ghefcdab"
+  echo "${1:6:2}${1:4:2}${1:2:2}${1:0:2}"
+}
+
+crmagic_hex="4372 3234" # Cr24
+version_hex="0200 0000" # 2
+pub_len_hex=$(byte_swap $(printf '%08x\n' $(ls -l "$pub" | awk '{print $5}')))
+sig_len_hex=$(byte_swap $(printf '%08x\n' $(ls -l "$sig" | awk '{print $5}')))
+(
+  echo "$crmagic_hex $version_hex $pub_len_hex $sig_len_hex" | xxd -r -p
+  cat "$pub" "$sig" "$zip"
+) > "$crx"
+echo "Wrote $crx"