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This is a hack that I put together to pull PCAP from multiple instances of stenographer, each with a different configuration file. It adds `mergecap` as a dependency, which is used to produce the final PCAP, which is then filtered through `tcpdump` as before.
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# Copyright 2014 Google Inc. All rights reserved. | |
# | |
# Licensed under the Apache License, Version 2.0 (the "License"); | |
# you may not use this file except in compliance with the License. | |
# You may obtain a copy of the License at | |
# | |
# http://www.apache.org/licenses/LICENSE-2.0 | |
# | |
# Unless required by applicable law or agreed to in writing, software | |
# distributed under the License is distributed on an "AS IS" BASIS, | |
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
# See the License for the specific language governing permissions and | |
# limitations under the License. | |
# | |
# stenographer - full packet to disk capture | |
# | |
# stenographer is a simple, fast method of writing live packets to disk, | |
# then requesting those packets after-the-fact for post-hoc analysis. | |
[Unit] | |
Description=packet capture to disk | |
After=syslog.target network.target | |
[Service] | |
Type=oneshot | |
RemainAfterExit=yes | |
ExecStart=/bin/true | |
ExecReload=/bin/true | |
WorkingDirectory=/etc/stenographer | |
[Install] | |
WantedBy=multi-user.target |
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# Copyright 2014 Google Inc. All rights reserved. | |
# | |
# Licensed under the Apache License, Version 2.0 (the "License"); | |
# you may not use this file except in compliance with the License. | |
# You may obtain a copy of the License at | |
# | |
# http://www.apache.org/licenses/LICENSE-2.0 | |
# | |
# Unless required by applicable law or agreed to in writing, software | |
# distributed under the License is distributed on an "AS IS" BASIS, | |
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
# See the License for the specific language governing permissions and | |
# limitations under the License. | |
# | |
# stenographer - full packet to disk capture | |
# | |
# stenographer is a simple, fast method of writing live packets to disk, | |
# then requesting those packets after-the-fact for post-hoc analysis. | |
[Unit] | |
Description=packet capture to disk | |
After=network.target | |
PartOf=stenographer.service | |
ReloadPropagatedFrom=stenographer.service | |
[Service] | |
User=stenographer | |
Group=stenographer | |
SyslogIdentifier=stenographer | |
LimitFSIZE=4294967296 | |
LimitNOFILE=1000000 | |
ExecStart=/usr/bin/stenographer -config /etc/stenographer/config.%i | |
ExecStopPost=/bin/pkill -9 stenotype | |
[Install] | |
WantedBy=multi-user.target |
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#!/bin/bash | |
# Copyright 2014 Google Inc. All rights reserved. | |
# | |
# Licensed under the Apache License, Version 2.0 (the "License"); | |
# you may not use this file except in compliance with the License. | |
# You may obtain a copy of the License at | |
# | |
# http://www.apache.org/licenses/LICENSE-2.0 | |
# | |
# Unless required by applicable law or agreed to in writing, software | |
# distributed under the License is distributed on an "AS IS" BASIS, | |
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
# See the License for the specific language governing permissions and | |
# limitations under the License. | |
if [ "$#" -lt 1 ]; then | |
cat >&2 <<EOF | |
$0 provides a simple method for reading logs out of stenographer. | |
Its first argument is the query to send to stenographer, all other arguments | |
are passed to TCPDump. | |
Examples: | |
# Print all packets for source IP 1.1.1.1 without DNS resolution (-n). | |
$0 'host 1.1.1.1' -n src host 1.1.1.1 | |
# Print all PSH packets between 1.1.1.1 and 2.2.2.2: | |
$0 'host 1.1.1.1 and host 2.2.2.2' -n 'tcp[tcpflags] & tcp-push != 0' | |
# Write all packets between 1.1.1.1 and 2.2.2.2 to disk. | |
'host 1.1.1.1 and host 2.2.2.2' -w /tmp/out.pcap | |
See README.md for more details on the Stenographer query language. | |
Set the STENOGRAPHER_CONFIG environmental variable to point to your stenographer | |
config if it's in a nonstandard place (defaults to /etc/stenographer/config). | |
$0 arguments are given before the filter. These include: | |
--limit-bytes X : Stop output once we've exceeded X bytes | |
--limit-packets X : Stop output once we've exceeded X packets | |
For example: | |
# Print first 6 packets or 2K bytes, whichever comes first, | |
# from source IP 1.1.1.1 | |
$0 --limit-packets 6 --limit-bytes 2048 'host 1.1.1.1' | |
EOF | |
exit 1 | |
fi | |
HEADERS="" | |
while true; do | |
case "$1" in | |
--limit-packets) | |
HEADERS="$HEADERS --header Steno-Limit-Packets:$2" | |
shift 2 | |
;; | |
--limit-bytes) | |
HEADERS="$HEADERS --header Steno-Limit-Bytes:$2" | |
shift 2 | |
;; | |
*) | |
STENOQUERY="$1" | |
shift | |
break | |
;; | |
esac | |
done | |
TCPDUMP=$(PATH=$PATH:/usr/local/sbin:/usr/sbin:/sbin which tcpdump) | |
STENOCURL=$(PATH=$(dirname "$0"):$PATH which stenocurl) | |
STENOGRAPHER_CONFIG_BASE=/etc/stenographer/config. | |
INTERFACES=$(ls ${STENOGRAPHER_CONFIG_BASE}* | awk -F. '{ print $2 }') | |
OUT=$(mktemp -d /tmp/stenoread.XXXXXXXXXX) || { echo "Failed to create temp file"; exit 1; } | |
echo "Running stenographer query '$STENOQUERY', piping to 'tcpdump $@'" >&2 | |
for IFACE in ${INTERFACES[@]} | |
do | |
STENOGRAPHER_CONFIG="${STENOGRAPHER_CONFIG_BASE}${IFACE}" | |
"$STENOCURL" /query \ | |
-d "$STENOQUERY" \ | |
--silent \ | |
--max-time 890 \ | |
--show-error $HEADERS | | |
"$TCPDUMP" -r /dev/stdin -s 0 -w ${OUT}/${IFACE}.pcap &>/dev/null | |
done | |
mergecap -w - ${OUT}/*.pcap | tcpdump -r /dev/stdin -s 0 "$@" | |
rm -rf ${OUT} |
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