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@trscavo trscavo/md_query.sh
Last active Nov 15, 2016

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Bash script to fetch SAML metadata via the Metadata Query Protocol
#!/bin/bash
# DEPRECATED: Use mdq_url.sh instead
###########################################################
# Fetch SAML metadata via the Metadata Query Protocol
#
# usage: md_query.sh [-tvq] [IDENTIFIER]
#
# where the -t option simply outputs the computed request URL (without
# querying for metadata). Omitting the -t option causes the script to
# invoke the curl command-line utility. The -v option causes curl to
# produce verbose output while the -q option causes curl to be silent.
# All options are mutually exclusive.
#
# The single command-line argument is an arbitrary IDENTIFIER as defined
# by the Metadata Query Protocol specification. In a SAML context the
# IDENTIFIER is usually a SAML entityID, which is used to fetch a single
# entity descriptor.
#
# NOTE: If both the IDENTIFIER and the -t option are omitted, the script
# will fetch ALL metadata served by the metadata query server.
#
# Note: set environment variable MDQ_BASE_URL before using this script.
#
# Example:
#
# $ export MDQ_BASE_URL=http://mdq.example.com/public
# $ md_query.sh -t https://sso.example.org/idp
# http://mdq.example.com/public/entities/https%3A%2F%2Fsso.example.org%2Fidp
#
# For details regarding the Metadata Query Protocol, see:
# https://github.com/iay/md-query
###########################################################
script_name=${0##*/} # equivalent to basename $0
# check the required environment variable
if [ -z "$MDQ_BASE_URL" ]; then
echo "ERROR: $script_name: environment variable MDQ_BASE_URL does not exist" >&2
exit 2
fi
# Construct a request URL per the MDQ Protocol specification
# See: https://github.com/iay/md-query
# To construct a reference to ALL entities served by the
# metadata query server, simply omit the second argument
construct_mdq_url () {
# construct_mdq_url <base_url> <url_encoded_id>
# make sure there are one or two command-line arguments
if [ $# -lt 1 -o $# -gt 2 ]; then
echo "ERROR: $FUNCNAME: incorrect number of arguments: $# (1 or 2 required)" >&2
return 2
fi
local base_url=$1
# strip the trailing slash from the base URL if necessary
local length="${#1}"
if [[ "${base_url:length-1:1}" == '/' ]]; then
base_url="${base_url:0:length-1}"
fi
# append the identifier if there is one
if [ $# -eq 2 ]; then
echo "${base_url}/entities/$2"
else
echo "${base_url}/entities"
fi
}
# URL-encode an arbitrary string
# see: https://gist.github.com/cdown/1163649
urlencode () {
# urlencode <string>
# make sure there is one (and only one) command-line argument
if [ $# -ne 1 ]; then
echo "ERROR: $FUNCNAME: incorrect number of arguments: $# (1 required)" >&2
return 2
fi
local length="${#1}"
for (( i = 0; i < length; i++ )); do
local c="${1:i:1}"
case "$c" in
[a-zA-Z0-9.~_-]) printf "$c" ;;
*) printf '%%%02X' "'$c"
esac
done
}
# process command-line option(s)
test_mode=false; verbose_mode=false; quiet_mode=false; curl_opts=
while getopts ":tvq" opt; do
case $opt in
t)
test_mode=true
verbose_mode=false
quiet_mode=false
curl_opts=
;;
v)
test_mode=false
verbose_mode=true
quiet_mode=false
curl_opts="--verbose"
;;
q)
test_mode=false
verbose_mode=false
quiet_mode=true
curl_opts="--silent"
;;
\?)
echo "ERROR: $script_name: Unrecognized option: -$OPTARG" >&2
exit 2
;;
esac
done
# construct the request URL
shift $(( OPTIND - 1 ))
if [ $# -eq 0 ]; then
request_url=$( construct_mdq_url $MDQ_BASE_URL )
elif [ $# -eq 1 ]; then
# URL-encode the identifier
encoded_id=$( urlencode "$1" )
return_status=$?
if [ "$return_status" -ne 0 ]; then
echo "ERROR: $script_name: failed to URL-encode the identifier" >&2
exit $return_status
fi
request_url=$( construct_mdq_url $MDQ_BASE_URL $encoded_id )
else
echo "ERROR: $script_name: incorrect number of arguments: $# (1 required)" >&2
exit 2
fi
# was the URL successfully constructed?
return_status=$?
if [ "$return_status" -ne 0 ]; then
echo "ERROR: $script_name: failed to construct the request URL" >&2
exit $return_status
fi
# use curl to request the resource (unless in test mode)
if $test_mode; then
echo $request_url
else
/usr/bin/curl $curl_opts $request_url
fi
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