update sigs and testing instructions for 14.04.5.12

Author: dougburks

checksums.txt

@@ -1,3 +1,8 @@
+14.04.5.12 ISO image
+md5sum 6d24a8877764dc6d39add434fd8a2927
+sha1sum 17535d382ce0043a76a5032eb42747dceffa7e7a
+sha256sum 3803010fdfca9e55e19d68286ce843a1fbd78bb6adfe33cbb3922f3b3165d3cc
+
 14.04.5.11 ISO image
 md5sum ee6dd85c45b751ab4a185b25b199d284
 sha1sum eb8d7e305ed30b1fd155bdf10a19cabdaafc033e

sigs/securityonion-14.04.5.12.iso.sig

@@ -0,0 +1,51 @@
+### 14.04.5.12 ISO image built on 2018/04/16
+
+### Download and Verify
+
+14.04.5.12 ISO image:  
+https://github.com/Security-Onion-Solutions/security-onion/releases/download/v14.04.5.12_20180416/securityonion-14.04.5.12.iso
+
+Signature for ISO image:  
+https://github.com/Security-Onion-Solutions/security-onion/raw/master/sigs/securityonion-14.04.5.12.iso.sig  
+
+Signing key:  
+https://raw.githubusercontent.com/Security-Onion-Solutions/security-onion/master/KEYS  
+
+For example, here are the steps you can use on most Linux distributions to download and verify our Security Onion ISO image.
+
+Download the signing key:  
+```
+wget https://raw.githubusercontent.com/Security-Onion-Solutions/security-onion/master/KEYS
+```
+
+Import the signing key:  
+```
+gpg --import KEYS
+```
+
+Download the signature file for the ISO:  
+```
+wget https://github.com/Security-Onion-Solutions/security-onion/raw/master/sigs/securityonion-14.04.5.12.iso.sig
+```
+
+Download the ISO image:  
+```
+wget https://github.com/Security-Onion-Solutions/security-onion/releases/download/v14.04.5.12_20180416/securityonion-14.04.5.12.iso
+```
+
+Verify the downloaded ISO image using the signature file:  
+```
+gpg --verify securityonion-14.04.5.12.iso.sig securityonion-14.04.5.12.iso
+```
+
+The output should show "Good signature" and the Primary key fingerprint should match what's shown below:
+```
+gpg: Signature made Mon 16 Apr 2018 03:34:49 PM EDT using RSA key ID ED6CF680
+gpg: Good signature from "Doug Burks <doug.burks@gmail.com>"
+gpg: WARNING: This key is not certified with a trusted signature!
+gpg:          There is no indication that the signature belongs to the owner.
+Primary key fingerprint: BD56 2813 E345 A068 5FBB  91D3 788F 62F8 ED6C F680
+```
+
+Once you've verified the ISO image, you're ready to proceed to our Installation guide:  
+https://github.com/Security-Onion-Solutions/security-onion/wiki/Installation