Mailing List Archive

convert: attempt to perform an operation not allowed by the security policy
Trying to use convert and getting security policy problem:

convert -density 300 document.pdf -fuzz 10% -channel rgba -fill none -opaque "#d2d2d2" -opaque "#b8b8b8" daily_appointment.pdf

convert: attempt to perform an operation not allowed by the security policy `PDF' @ error/constitute.c/IsCoderAuthorized/449.
convert: no images defined `daily_appointment.pdf' @ error/convert.c/ConvertImageCommand/3342


Which security policy is it? Output of: cat /etc/ImageMagick-7/policy.xml

<?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 '' domain NMTOKEN #REQUIRED
name NMTOKEN #IMPLIED pattern CDATA #IMPLIED rights NMTOKEN #IMPLIED
stealth NMTOKEN #IMPLIED value CDATA #IMPLIED>
]>
<!--
Configure ImageMagick policies.

Domains include system, delegate, coder, filter, 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:

<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/*" />

Lets prevent users from executing any image filters:

<policy domain="filter" rights="none" pattern="*" />

Any large image is cached 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}" />
-->
<policymap>
<!-- https://www.kb.cert.org/vuls/id/332928 mitigation / https://bugs.gentoo.org/664236 -->
<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="none" pattern="PDF" />
<policy domain="coder" rights="none" pattern="XPS" />

<!-- <policy domain="resource" name="temporary-path" value="/tmp"/> -->
<!-- <policy domain="resource" name="memory" value="2GiB"/> -->
<!-- <policy domain="resource" name="map" value="4GiB"/> -->
<!-- <policy domain="resource" name="width" value="10KP"/> -->
<!-- <policy domain="resource" name="height" value="10KP"/> -->
<!-- <policy domain="resource" name="list-length" value="128"/> -->
<!-- <policy domain="resource" name="area" value="100MP"/> -->
<!-- <policy domain="resource" name="disk" value="16EiB"/> -->
<!-- <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="coder" rights="none" pattern="MVG" /> -->
<!-- <policy domain="module" rights="none" pattern="{PS,PDF,XPS}" /> -->
<!-- <policy domain="delegate" rights="none" pattern="HTTPS" /> -->
<!-- <policy domain="path" rights="none" pattern="@*" /> -->
<!-- <policy domain="cache" name="memory-map" value="anonymous"/> -->
<!-- <policy domain="cache" name="synchronize" value="True"/> -->
<!-- <policy domain="cache" name="shared-secret" value="passphrase" stealth="true"/> -->
<!-- <policy domain="system" name="max-memory-request" value="256MiB"/> -->
<!-- <policy domain="cache" name="synchronize" value="true"/> -->
<!-- <policy domain="system" name="shred" value="1"/> -->
<!-- <policy domain="system" name="font" value="/path/to/unicode-font.ttf"/> -->
<policy domain="Undefined" rights="none"/>
</policymap>

--
Thelma
Re: convert: attempt to perform an operation not allowed by the security policy [ In reply to ]
Am Tue, May 02, 2023 at 03:07:30PM -0600 schrieb thelma@sys-concept.com:
>Trying to use convert and getting security policy problem:
>
>convert -density 300 document.pdf -fuzz 10% -channel rgba -fill none -opaque "#d2d2d2" -opaque "#b8b8b8" daily_appointment.pdf
>
>convert: attempt to perform an operation not allowed by the security policy `PDF' @ error/constitute.c/IsCoderAuthorized/449.
>convert: no images defined `daily_appointment.pdf' @ error/convert.c/ConvertImageCommand/3342
>
>
>Which security policy is it? Output of: cat /etc/ImageMagick-7/policy.xml
>
><policymap>
> <!-- https://www.kb.cert.org/vuls/id/332928 mitigation / https://bugs.gentoo.org/664236 -->
> <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="none" pattern="PDF" />
> <policy domain="coder" rights="none" pattern="XPS" />

By default conversion to pdf are forbidden. You may want to read the gentoo bug
indicated in the file and if you still want to allow convert to create pdf
files, remove or comment the line with pattern="PDF".
Re: convert: attempt to perform an operation not allowed by the security policy [ In reply to ]
On 5/2/23 16:25, Hoël Bézier wrote:
> Am Tue, May 02, 2023 at 03:07:30PM -0600 schrieb thelma@sys-concept.com:
>> Trying to use convert and getting security policy problem:
>>
>> convert -density 300 document.pdf -fuzz 10% -channel rgba -fill none -opaque "#d2d2d2" -opaque "#b8b8b8" daily_appointment.pdf
>>
>> convert: attempt to perform an operation not allowed by the security policy `PDF' @ error/constitute.c/IsCoderAuthorized/449.
>> convert: no images defined `daily_appointment.pdf' @ error/convert.c/ConvertImageCommand/3342
>>
>>
>> Which security policy is it? Output of:  cat /etc/ImageMagick-7/policy.xml
>>
>> <policymap>
>>   <!-- https://www.kb.cert.org/vuls/id/332928 mitigation / https://bugs.gentoo.org/664236 -->
>>   <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="none" pattern="PDF" />
>>   <policy domain="coder" rights="none" pattern="XPS" />
>
> By default conversion to pdf are forbidden. You may want to read the gentoo bug indicated in the file and if you still want to allow convert to create pdf files, remove or comment the line with pattern="PDF".

You are correct, changing it to:
<policy domain="coder" rights="read|write" pattern="PDF" />

solved the problem.