Merge pull request #917 from gianlucam76/cves-3.13

CVEs

.dockerignore

@@ -1,5 +1,6 @@
 *
 !k8s-install/scripts/install-cni.sh
 !k8s-install/scripts/calico.conf.default
+!k8s-install/scripts/clean.sh
 !bin/
 !LICENSE

Dockerfile.amd64

@@ -12,7 +12,25 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM registry.access.redhat.com/ubi8/ubi-minimal:8.1-407
+FROM registry.access.redhat.com/ubi8/ubi-minimal:8.2-301.1592810506 AS base
+
+COPY k8s-install/scripts/clean.sh /clean.sh
+
+RUN touch /in-the-container
+
+RUN microdnf install hostname
+
+RUN mkdir /licenses
+COPY LICENSE /licenses/
+
+RUN microdnf update
+
+SHELL ["/bin/bash", "-c"]
+RUN  /clean.sh "/bin/sed" "/bin/mkdir" "/bin/cp" "/bin/mv" "/bin/cat" "/bin/touch" "/bin/chmod" \
+"/bin/grep"  "/bin/hostname" "/bin/basename" "/bin/base64"
+
+FROM scratch
+SHELL ["/bin/sh", "-c"]
 
 ARG GIT_VERSION=unknown
 
@@ -24,13 +42,16 @@ LABEL name="Calico Networking for CNI" \
       description="Calico Networking for CNI includes a CNI networking plugin and CNI IPAM plugin" \
       maintainer="[email protected]"
 
+COPY --from=base /licenses /licenses
+COPY --from=base /bin /bin
+COPY --from=base /lib64 /lib64
+COPY --from=base /usr/lib64 /usr/lib64
+COPY --from=base /usr/bin /usr/bin
+
 ADD bin/amd64/ /opt/cni/bin/
 ADD k8s-install/scripts/install-cni.sh /install-cni.sh
 ADD k8s-install/scripts/calico.conf.default /calico.conf.tmp
 
-RUN microdnf install hostname && mkdir /licenses
-COPY LICENSE /licenses
-
 ENV PATH=$PATH:/opt/cni/bin
 WORKDIR /opt/cni/bin
-CMD ["/opt/cni/bin/calico"]
+CMD ["/opt/cni/bin/calico"]

k8s-install/scripts/clean.sh

@@ -0,0 +1,150 @@
+#!/bin/bash
+
+# 1) the idea of this script is to start with list of tools needed (passed as an argument + the tools script itself needs)
+# 2) Find all libraries such a tools depend on.
+# 3) Remove everything from /lib64 and /usr/lib64 but the libraries found in #2
+# 4) Remove everything from /bin and /usr/bin but the tools needed (#1) 
+
+# Sanity check: the file is created by the Dockerfile. 
+# Abort the script is such a file is not present. This will avoid accidentally running the script.
+if [ ! -f /in-the-container ]; then
+  echo "Don't run this outside the container!"
+  exit 1
+fi
+
+# folllowing are needed by script itself
+basicNeed=( "/bin/ls" "/bin/rm" "/bin/bash" "/bin/sh" "/bin/coreutils" )
+# Array of basic tools needed by entrypoint and user_setup.
+for i in "$@"; do
+    if [[ ! " ${basicNeed[@]} " =~ " ${i} " ]]; then
+        basicNeed+=("$i")
+    fi
+done
+libraries=()
+
+# Fine all libraries for the passed argument.
+# Output of following command returns back full path of each dependency. 
+function findDependencies()
+{
+    t=$1
+    dependencies=$(ldd "${t}" \
+        | grep -P "\.so\.\d?" \
+        | sed -e '/^[^\t]/ d' \
+        | sed -e 's/\t//' \
+        | sed -e 's/.*=..//' \
+        | sed -e 's/ (0.*)//')
+}
+
+# Recursively removes all that is not needed.
+# If the argurment is a directory, then it recursively consider all subdirectories and files.
+# A directory is kept only if is not empty.
+# If the argument is a file, then it is kept only if present in ${libraries[@]} (which by the time this method is
+# invoked contains already all libraries that are needed).
+function cleanUp()
+{
+    if [[ -d $1 ]]; then
+        for entry in "$1"/*; do
+            cleanUp $entry
+        done
+        # Remove empty directory
+        if [ -z "$(ls -A $1)" ]; then
+            rmdir $1
+        fi
+    else
+        remove=1
+        for library in "${libraries[@]}"; do
+            if [[ "$1" == *"$library"* ]]; then
+                remove=0
+                break
+            fi
+        done
+        if [ "$remove" -eq 1 ]; then
+            rm -f ${1}
+        fi
+    fi
+}
+
+# Get all shared libraries which are needed by basicNeed
+# basicNeed is the list of tools the script itself depend on plus any tool passed as argument of the script
+# from Dockerfile.
+echo "Finding dependencies for "${basicNeed[@]}""
+for i in "${basicNeed[@]}"; do
+    findDependencies $i
+    for library in $dependencies; do 
+        if test -f "$library"; then
+             if [[ ! " ${libraries[@]} " =~ " ${library} " ]]; then
+                libraries+=( "$library" )
+            fi
+        fi
+    done
+done
+
+# Recursively find all that is needed (a needed library might depend itself on other libraries).
+# Everytime we find a new library we depend on, a new iteration is needed.
+loop=1
+while [ "$loop" -eq 1 ]; do 
+    loop=0
+    newDependencies=()
+    for library in "${libraries[@]}"; do
+        findDependencies $library
+        for l in $dependencies; do
+            if test -f "$l"; then
+                if [[ ! " ${libraries[@]} " =~ " ${l} " ]]; then
+                    newDependencies+=( "$l" )
+                    loop=1
+                fi
+            fi
+        done
+    done
+    for i in "${newDependencies[@]}"; do
+        libraries+=( "$i" )
+    done
+done
+
+paths=( "/lib64" "/usr/lib64" )
+# Recursively find all that is needed
+loop=1
+while [ "$loop" -eq 1 ]; do 
+    loop=0
+    newDependencies=()
+    for library in "${libraries[@]}"; do
+        rlink=$(readlink "$library")
+        for l in $rlink; do
+            for p in  "${paths[@]}"; do
+                if [[ ! " ${libraries[@]} " =~ " ${p}/${l} " ]]; then
+                    if test -f "${p}/${l}"; then              
+                        loop=1
+                        newDependencies+=( "${p}/${l}" )
+                    fi
+                fi
+            done
+        done
+    done
+    for i in "${newDependencies[@]}"; do
+        libraries+=( "$i" )
+    done
+done
+
+echo  "Keeping ${libraries[@]}"
+
+for i in  "${paths[@]}"; do
+    cleanUp $i
+done
+
+paths=( "/bin" "/usr/bin" )
+for i in  "${paths[@]}"; do
+    for entry in "$i"/*; do
+      remove=1
+        for i in "${basicNeed[@]}"; do
+            if [[ "$entry" == *"$i" ]]; then
+                remove=0
+                break
+            fi
+        done
+        if [ "$remove" -eq 1 ]; then
+            rm -f ${entry}
+        fi
+    done
+done
+
+rm /in-the-container