tests: Add tests for reproducible builds

Test the 'tar' and 'kernel+initrd' formats for now.

Signed-off-by: Rolf Neugebauer <rn@rneugeba.io>

test/cases/000_build/010_reproducible/000_tar/test.sh

@@ -0,0 +1,25 @@
+#!/bin/sh
+# SUMMARY: Check that tar output format build is reproducible
+# LABELS:
+
+set -e
+
+# Source libraries. Uncomment if needed/defined
+#. "${RT_LIB}"
+. "${RT_PROJECT_ROOT}/_lib/lib.sh"
+
+NAME=check
+
+clean_up() {
+	rm -f ${NAME}*
+}
+
+trap clean_up EXIT
+
+# -disable-content-trust to speed up the test
+linuxkit build -disable-content-trust -format tar -name "${NAME}-1" ../test.yml
+linuxkit build -disable-content-trust -format tar -name "${NAME}-2" ../test.yml
+
+diff -q "${NAME}-1.tar" "${NAME}-2.tar" || exit 1
+
+exit 0

test/cases/000_build/010_reproducible/002_kernel+initrd/test.sh

@@ -0,0 +1,27 @@
+#!/bin/sh
+# SUMMARY: Check that kernel+initrd output format build is reproducible
+# LABELS:
+
+set -e
+
+# Source libraries. Uncomment if needed/defined
+#. "${RT_LIB}"
+. "${RT_PROJECT_ROOT}/_lib/lib.sh"
+
+NAME=check
+
+clean_up() {
+	rm -f ${NAME}*
+}
+
+trap clean_up EXIT
+
+# -disable-content-trust to speed up the test
+linuxkit build -disable-content-trust -format kernel+initrd -name "${NAME}-1" ../test.yml
+linuxkit build -disable-content-trust -format kernel+initrd -name "${NAME}-2" ../test.yml
+
+diff -q "${NAME}-1-cmdline"    "${NAME}-2-cmdline"    || exit 1
+diff -q "${NAME}-1-kernel"     "${NAME}-2-kernel"     || exit 1
+diff -q "${NAME}-1-initrd.img" "${NAME}-2-initrd.img" || exit 1
+
+exit 0

test/cases/000_build/010_reproducible/test.yml

@@ -0,0 +1,52 @@
+# NOTE: Images build from this file likely do not run
+kernel:
+  image: linuxkit/kernel:4.14.90
+  cmdline: "console=ttyS0"
+init:
+  - linuxkit/init:c563953a2277eb73a89d89f70e4b6dcdcfebc2d1
+  - linuxkit/runc:83d0edb4552b1a5df1f0976f05f442829eac38fe
+  - linuxkit/containerd:326b096cd5fbab0f864e52721d036cade67599d6
+
+onboot:
+  - name: dhcpcd
+    image: linuxkit/dhcpcd:v0.6
+    command: ["/sbin/dhcpcd", "--nobackground", "-f", "/dhcpcd.conf", "-1"]
+    # Add some random unsorted caps
+    capabilities:
+      - CAP_SETGID
+      - CAP_DAC_OVERRIDE
+
+services:
+  - name: testservice
+    image: linuxkit/ip:v0.6
+    # Some environments
+    env:
+      - BENV=true
+      - ARANDOMENV=foobar
+    # Some mounts
+    mounts:
+      - type: cgroup
+        options: ["rw","nosuid","noexec","nodev","relatime"]
+      - type: overlay
+        source: overlay
+        destination: writeable-host-etc
+        options: ["rw", "lowerdir=/etc", "upperdir=/run/hostetc/upper", "workdir=/run/hostetc/work"]
+    # Some binds
+    binds:
+      - /var/run:/var/run
+      - /foobar:/foobar
+      - /etc/foobar:/etc/foobar
+      - /etc/aaa:/etc/aaa
+    # And some runtime settings
+    runtime:
+      mkdir: ["/var/lib/docker"]
+      mkdir: ["/var/lib/aaa"]
+
+files:
+  - path: etc/linuxkit-config
+    metadata: yaml
+
+trust:
+  org:
+    - linuxkit
+    - library