verifypackages in docker file

Dockerfile.linux

@@ -1,5 +1,19 @@
 #todo pin hash of shared_functions.sh
-# Stage 1: Downloader
+
+# Stage 1: Confirm provided deb md5sums
+FROM ubuntu:16.04@sha256:1f1a2d56de1d604801a9671f301190704c25d604a416f59e03c04f5c6ffee0d6 as verifypackages
+
+RUN apt-get update && \
+    apt-get install -y gpg xz-utils wget && \
+    rm -rf /var/lib/apt/lists/*
+
+COPY shared_functions.sh /sources/shared_functions.sh
+RUN chmod +x /sources/shared_functions.sh
+
+# Single CMD with all required commands
+RUN /bin/bash -c "source shared_functions.sh && get_packages && verify_packages"
+
+# Stage 2: Downloader
 FROM ubuntu:16.04@sha256:1f1a2d56de1d604801a9671f301190704c25d604a416f59e03c04f5c6ffee0d6 as downloader
 
 ARG THREADS=3
@@ -18,7 +32,7 @@ RUN chmod +x /sources/shared_functions.sh
 # Single CMD with all required commands
 RUN /bin/bash -c "source shared_functions.sh && get_debs_downloader && download_all_tarballs"
 
-# Stage 2: Git Cloner
+# Stage 3: Git Cloner
 FROM ubuntu:16.04@sha256:1f1a2d56de1d604801a9671f301190704c25d604a416f59e03c04f5c6ffee0d6 as gitcloner
 
 ARG THREADS=3
@@ -37,7 +51,7 @@ RUN /bin/bash -c "source shared_functions.sh && get_debs_gitcloner"
 RUN --network=none /bin/bash -c "source shared_functions.sh && install_debs_gitcloner" 
 RUN /bin/bash -c "source shared_functions.sh && clone_git_repos"
 
-# Stage 3: Builder
+# Stage 4: Builder
 FROM ubuntu:16.04@sha256:1f1a2d56de1d604801a9671f301190704c25d604a416f59e03c04f5c6ffee0d6 as builder
 
 ARG THREADS=3

shared_functions.sh

@@ -718,7 +718,7 @@ check_md5sums() {
     check_array debs_tarballs
 }
 
-# get_packages / verify_packages adapted from featherwallet v2.2.1
+# get_packages / verify_packages adapted from featherwallet v2.1.2
 
 BASE_URI="http://archive.ubuntu.com/ubuntu/dists"
 ARCH="amd64"