/usr/share/wireshark/diameter/ is in libwireshark-data 1.8.2-5wheezy18.
This file is owned by root:root, with mode 0o755.
..
/usr/share/wireshark/diameter/Cisco.xml
/usr/share/wireshark/diameter/Ericsson.xml
/usr/share/wireshark/diameter/TGPPGmb.xml
/usr/share/wireshark/diameter/TGPPRx.xml
/usr/share/wireshark/diameter/TGPPS9.xml
/usr/share/wireshark/diameter/TGPPSh.xml
/usr/share/wireshark/diameter/Vodafone.xml
/usr/share/wireshark/diameter/chargecontrol.xml
/usr/share/wireshark/diameter/dictionary.dtd
/usr/share/wireshark/diameter/dictionary.xml
/usr/share/wireshark/diameter/eap.xml
/usr/share/wireshark/diameter/etsie2e4.xml
/usr/share/wireshark/diameter/gqpolicy.xml
/usr/share/wireshark/diameter/imscxdx.xml
/usr/share/wireshark/diameter/mobileipv4.xml
/usr/share/wireshark/diameter/mobileipv6.xml
/usr/share/wireshark/diameter/nasreq.xml
/usr/share/wireshark/diameter/sip.xml
/usr/share/wireshark/diameter/sunping.xml