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|
From: =?utf-8?q?Bastien_Roucari=C3=A8s?= <rouca@debian.org>
Date: Sat, 21 Oct 2023 14:11:43 +0000
Subject: Add a debian policy
Install also other policy
---
config/Makefile.am | 1 +
config/policy-debian.xml | 156 +++++++++++++++++++++++++++++++++++++++++++++++
configure.ac | 6 +-
3 files changed, 160 insertions(+), 3 deletions(-)
create mode 100644 config/policy-debian.xml
diff --git a/config/Makefile.am b/config/Makefile.am
index a3c12d6..1015263 100644
--- a/config/Makefile.am
+++ b/config/Makefile.am
@@ -62,6 +62,7 @@ CONFIG_EXTRA_DIST = \
config/locale.xml \
config/log.xml \
config/mime.xml \
+ config/policy-debian.xml \
config/policy-limited.xml \
config/policy-open.xml \
config/policy-secure.xml \
diff --git a/config/policy-debian.xml b/config/policy-debian.xml
new file mode 100644
index 0000000..4b878ce
--- /dev/null
+++ b/config/policy-debian.xml
@@ -0,0 +1,156 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE policymap [
+<!ELEMENT policymap (policy)*>
+<!ATTLIST policymap xmlns CDATA #FIXED "">
+<!ELEMENT policy EMPTY>
+<!ATTLIST policy xmlns CDATA #FIXED "">
+<!ATTLIST policy domain NMTOKEN #REQUIRED>
+<!ATTLIST policy name NMTOKEN #IMPLIED>
+<!ATTLIST policy pattern CDATA #IMPLIED>
+<!ATTLIST policy rights NMTOKEN #IMPLIED>
+<!ATTLIST policy stealth NMTOKEN #IMPLIED>
+<!ATTLIST policy value CDATA #IMPLIED>
+]>
+<!--
+ Creating a security policy that fits your specific local environment
+ before making use of ImageMagick is highly advised. You can find guidance on
+ setting up this policy at https://imagemagick.org/script/security-policy.php,
+ and it's important to verify your policy using the validation tool located
+ at https://imagemagick-secevaluator.doyensec.com/.
+
+
+ Open ImageMagick security policy:
+
+ The default policy for ImageMagick installations is the open security
+ policy. This policy is designed for usage in secure settings like those
+ protected by firewalls or within Docker containers. Within this framework,
+ ImageMagick enjoys broad access to resources and functionalities. This policy
+ provides convenient and adaptable options for image manipulation. However,
+ it's important to note that it might present security vulnerabilities in
+ less regulated conditions. Thus, organizations should thoroughly assess
+ the appropriateness of the open policy according to their particular use
+ case and security prerequisites.
+
+ ImageMagick security policies in a nutshell:
+
+ Domains include system, delegate, coder, filter, module, path, or resource.
+
+ Rights include none, read, write, execute and all. 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, use this policy:
+
+ <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" />
+
+ 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/*" />
+
+ Prevent users from executing any image filters:
+
+ <policy domain="filter" rights="none" pattern="*" />
+
+ Cache large images to disk rather than memory:
+
+ <policy domain="resource" name="area" value="1GP"/>
+
+ Use the default system font unless overridden by the application:
+
+ <policy domain="system" name="font" value="/usr/share/fonts/favorite.ttf"/>
+
+ 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).
+
+ Rules are processed in order. Here we want to restrict ImageMagick to only
+ read or write a small subset of proven web-safe image types:
+
+ <policy domain="delegate" rights="none" pattern="*" />
+ <policy domain="filter" rights="none" pattern="*" />
+ <policy domain="coder" rights="none" pattern="*" />
+ <policy domain="coder" rights="read|write" pattern="{GIF,JPEG,PNG,WEBP}" />
+
+ See https://imagemagick.org/script/security-policy.php for a deeper
+ understanding of ImageMagick security policies.
+-->
+<policymap>
+ <policy domain="Undefined" rights="none"/>
+ <!-- Set maximum parallel threads. -->
+ <!-- <policy domain="resource" name="thread" value="2"/> -->
+ <!-- Set maximum time in seconds. When this limit is exceeded, an exception
+ is thrown and processing stops. -->
+ <!-- <policy domain="resource" name="time" value="120"/> -->
+ <!-- Set maximum number of open pixel cache files. When this limit is
+ exceeded, any subsequent pixels cached to disk are closed and reopened
+ on demand. -->
+ <!-- <policy domain="resource" name="file" value="768"/> -->
+ <!-- Set maximum amount of memory in bytes to allocate for the pixel cache
+ from the heap. When this limit is exceeded, the image pixels are cached
+ to memory-mapped disk. -->
+ <policy domain="resource" name="memory" value="1024MiB"/>
+ <!-- Set maximum amount of memory map in bytes to allocate for the pixel
+ cache. When this limit is exceeded, the image pixels are cached to
+ disk. -->
+ <policy domain="resource" name="map" value="2048MiB"/>
+ <!-- Set the maximum width * height of an image that can reside in the pixel
+ cache memory. Images that exceed the area limit are cached to disk. -->
+ <policy domain="resource" name="area" value="256MP"/>
+ <!-- Set maximum amount of disk space in bytes permitted for use by the pixel
+ cache. When this limit is exceeded, the pixel cache is not be created
+ and an exception is thrown. -->
+ <policy domain="resource" name="disk" value="2GiB"/>
+ <!-- Set the maximum length of an image sequence. When this limit is
+ exceeded, an exception is thrown. -->
+ <!-- <policy domain="resource" name="list-length" value="32"/> -->
+ <!-- Set the maximum width of an image. When this limit is exceeded, an
+ exception is thrown. -->
+ <policy domain="resource" name="width" value="32KP"/>
+ <!-- Set the maximum height of an image. When this limit is exceeded, an
+ exception is thrown. -->
+ <policy domain="resource" name="height" value="32KP"/>
+ <!-- Periodically yield the CPU for at least the time specified in
+ milliseconds. -->
+ <!-- <policy domain="resource" name="throttle" value="2"/> -->
+ <!-- Do not create temporary files in the default shared directories, instead
+ specify a private area to store only ImageMagick temporary files. -->
+ <!-- <policy domain="resource" name="temporary-path" value="/magick/tmp/"/> -->
+ <!-- Force memory initialization by memory mapping select memory
+ allocations. -->
+ <!-- <policy domain="cache" name="memory-map" value="anonymous"/> -->
+ <!-- Ensure all image data is fully flushed and synchronized to disk. -->
+ <!-- <policy domain="cache" name="synchronize" value="true"/> -->
+ <!-- Replace passphrase for secure distributed processing -->
+ <!-- <policy domain="cache" name="shared-secret" value="secret-passphrase" stealth="true"/> -->
+ <!-- Do not permit any delegates to execute. -->
+ <!-- <policy domain="delegate" rights="none" pattern="*"/> -->
+ <!-- Do not permit any image filters to load. -->
+ <!-- <policy domain="filter" rights="none" pattern="*"/> -->
+ <!-- Don't read/write from/to stdin/stdout. -->
+ <!-- <policy domain="path" rights="none" pattern="-"/> -->
+ <!-- don't read sensitive paths. -->
+ <!-- <policy domain="path" rights="none" pattern="/etc/*"/> -->
+ <!-- Indirect reads are not permitted. -->
+ <policy domain="path" rights="none" pattern="@*"/>
+ <!-- These image types are security risks on read, but write is fine -->
+ <!-- <policy domain="module" rights="write" pattern="{MSL,MVG,PS,SVG,URL,XPS}"/> -->
+ <!-- This policy sets the number of times to replace content of certain
+ memory buffers and temporary files before they are freed or deleted. -->
+ <!-- <policy domain="system" name="shred" value="1"/> -->
+ <!-- Enable the initialization of buffers with zeros, resulting in a minor
+ performance penalty but with improved security. -->
+ <!-- <policy domain="system" name="memory-map" value="anonymous"/> -->
+ <!-- Set the maximum amount of memory in bytes that are permitted for
+ allocation requests. -->
+ <!-- <policy domain="system" name="max-memory-request" value="256MiB"/> -->
+ <policy domain="delegate" rights="none" pattern="URL" />
+ <policy domain="delegate" rights="none" pattern="HTTPS" />
+ <policy domain="delegate" rights="none" pattern="HTTP" />
+</policymap>
diff --git a/configure.ac b/configure.ac
index eb7b9ee..be44a36 100644
--- a/configure.ac
+++ b/configure.ac
@@ -827,10 +827,10 @@ m4_define([_MAGICK_SECURITY_POLICY],
[m4_define([MAGICK_SECURITY_POLICY_DEFAULT], [m4_if($1, limited, limited, m4_if($1, secure, secure, open))])dnl
AC_MSG_CHECKING([which variant of security policy to enforce])
AC_ARG_WITH([security-policy],
- [AS_HELP_STRING([--with-security-policy=open|limited|secure|websafe],
+ [AS_HELP_STRING([--with-security-policy=open|limited|secure|websafe|debian],
[security policy variant to enforce, @<:@default=]MAGICK_SECURITY_POLICY_DEFAULT[@:>@.])],
[case $withval in
- open|limited|secure|websafe)
+ open|limited|secure|websafe|debian)
security_policy=$withval
;;
*)
@@ -844,7 +844,7 @@ m4_define([_MAGICK_SECURITY_POLICY],
AC_MSG_RESULT([$security_policy])
]) # MAGICK_SECURITY_POLICY
-_MAGICK_SECURITY_POLICY([open])
+_MAGICK_SECURITY_POLICY([debian])
AC_SUBST([MAGICK_SECURITY_POLICY])
# Disable/Enable support for full delegate paths
|
