ImageMagick policy

https://github.com/linuxserver/docker-calibre-web/issues/75

README.md

@@ -243,6 +243,7 @@ Once registered you can define the dockerfile to use with `-f Dockerfile.aarch64
 
 ## Versions
 
+* **06.05.20:** - Add libxslt1.1 and update ImageMagick policy
 * **19.01.20:** - Adding LDAP libs.
 * **13.10.19:** - Migrate to Python3.
 * **01.08.19:** - Add libxcomposite1.

readme-vars.yml

@@ -70,6 +70,7 @@ app_setup_block: |
 
 # changelog
 changelogs:
+  - { date: "06.05.20:", desc: "Add libxslt1.1 and update ImageMagick policy" }
   - { date: "19.01.20:", desc: "Adding LDAP libs." }
   - { date: "13.10.19:", desc: "Migrate to Python3." }
   - { date: "01.08.19:", desc: "Add libxcomposite1." }

root/defaults/policy.xml

@@ -0,0 +1,80 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE policymap [
+<!ELEMENT policymap (policy)+>
+<!ELEMENT policy (#PCDATA)>
+<!ATTLIST policy domain (delegate|coder|filter|path|resource) #IMPLIED>
+<!ATTLIST policy name CDATA #IMPLIED>
+<!ATTLIST policy rights CDATA #IMPLIED>
+<!ATTLIST policy pattern CDATA #IMPLIED>
+<!ATTLIST policy value CDATA #IMPLIED>
+]>
+<!--
+  Configure ImageMagick policies.
+
+  Domains include system, delegate, coder, filter, path, or resource.
+
+  Rights include none, read, write, and execute.  Use | to combine them,
+  for example: "read | write" to permit read from, or write to, a path.
+
+  Use a glob expression as a pattern.
+
+  Suppose we do not want users to process MPEG video images:
+
+    <policy domain="delegate" rights="none" pattern="mpeg:decode" />
+
+  Here we do not want users reading images from HTTP:
+
+    <policy domain="coder" rights="none" pattern="HTTP" />
+
+  Lets prevent users from executing any image filters:
+
+    <policy domain="filter" rights="none" pattern="*" />
+
+  The /repository file system is restricted to read only.  We use a glob
+  expression to match all paths that start with /repository:
+  
+    <policy domain="path" rights="read" pattern="/repository/*" />
+
+  Let's prevent possible exploits by removing the right to use indirect reads.
+
+    <policy domain="path" rights="none" pattern="@*" />
+
+  Any large image is cached to disk rather than memory:
+
+    <policy domain="resource" name="area" value="1GB"/>
+
+  Define arguments for the memory, map, area, width, height, and disk resources
+  with SI prefixes (.e.g 100MB).  In addition, resource policies are maximums
+  for each instance of ImageMagick (e.g. policy memory limit 1GB, -limit 2GB
+  exceeds policy maximum so memory limit is 1GB).
+-->
+<policymap>
+  <!-- <policy domain="resource" name="temporary-path" value="/tmp"/> -->
+  <policy domain="resource" name="memory" value="256MiB"/>
+  <policy domain="resource" name="map" value="512MiB"/>
+  <policy domain="resource" name="width" value="16KP"/>
+  <policy domain="resource" name="height" value="16KP"/>
+  <policy domain="resource" name="area" value="128MB"/>
+  <policy domain="resource" name="disk" value="1GiB"/>
+  <!-- <policy domain="resource" name="file" value="768"/> -->
+  <!-- <policy domain="resource" name="thread" value="4"/> -->
+  <!-- <policy domain="resource" name="throttle" value="0"/> -->
+  <!-- <policy domain="resource" name="time" value="3600"/> -->
+  <!-- <policy domain="system" name="precision" value="6"/> -->
+  <!-- not needed due to the need to use explicitly by mvg: -->
+  <!-- <policy domain="delegate" rights="none" pattern="MVG" /> -->
+  <!-- use curl -->
+  <policy domain="delegate" rights="none" pattern="URL" />
+  <policy domain="delegate" rights="none" pattern="HTTPS" />
+  <policy domain="delegate" rights="none" pattern="HTTP" />
+  <!-- in order to avoid to get image with password text -->
+  <policy domain="path" rights="none" pattern="@*"/>
+  <policy domain="cache" name="shared-secret" value="passphrase" stealth="true"/>
+  <!-- disable ghostscript format types -->
+  <policy domain="coder" rights="none" pattern="PS" />
+  <policy domain="coder" rights="none" pattern="PS2" />
+  <policy domain="coder" rights="none" pattern="PS3" />
+  <policy domain="coder" rights="none" pattern="EPS" />
+  <policy domain="coder" rights="read" pattern="PDF" />
+  <policy domain="coder" rights="none" pattern="XPS" />
+</policymap>

root/etc/cont-init.d/30-config

@@ -1,5 +1,11 @@
 #!/usr/bin/with-contenv bash
 
+# create symlinks for imagemagick policy.xml
+[[ -f /etc/ImageMagick-6/policy.xml ]] && \
+	rm /etc/ImageMagick-6/policy.xml
+[[ ! -L /etc/ImageMagick-6/policy.xml ]] && \
+	ln -s /defaults/policy.xml /etc/ImageMagick-6/policy.xml
+
 # create symlinks for database and log
 [[ ! -f /config/app.db ]] && \
 	cp /defaults/app.db /config/app.db