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stenoread(1) stenoread(1)


stenoread - read logs out of Stenographer


stenoread <stenographer_query> [tcpdump_arguments]


The stenoread command line script automates pulling packets from Stenographer and presenting them in a usable format to analysts. It requests raw packets from stenographer, then runs them through tcpdump to provide a more full-featured formatting/filtering experience.

The first argument to stenoread is a stenographer query (see below). All other arguments are passed to tcpdump. For example:

        # Request all packets from IP port 6543, then do extra filtering by
        # TCP flag, which typical stenographer does not support.
        $ stenoread 'host and port 6543' 'tcp[tcpflags] & tcp-push != 0'
        # Request packets on port 8765, disabling IP resolution (-n) and showing
        # link-level headers (-e) when printing them out.
        $ stenoread 'port 8765' -n -e
        # Request packets for any IPs in the range, writing them
        #out to a local PCAP file so they can be opened in Wireshark.
        $ stenoread 'net' -w /tmp/output_for_wireshark.pcap


A user requests packets from stenographer by specifying them with a very simple query language. This language is a simple subset of BPF, and includes the primitives:

        host          # Single IP address (hostnames not allowed)
        net         # Network with CIDR
        net mask  # Network with mask
        port 80               # Port number (UDP or TCP)
        ip proto 6            # IP protocol number 6
        icmp                  # equivalent to 'ip proto 1'
        tcp                   # equivalent to 'ip proto 6'
        udp                   # equivalent to 'ip proto 17'
        # Stenographer-specific time additions:
        before 2012-11-03T11:05:00Z      # Packets before a specific time (UTC)
        after 2012-11-03T11:05:00-0700   # Packets after a specific time (with TZ)
        before 45m ago        # Packets before a relative time
        before 3h ago         # Packets after a relative time
Primitives can be combined with and/&& and with or/||, which have equal precedence and evaluate left-to-right. Parens can also be used to group:

        (udp and port 514) or (tcp and port 8080)


Set the STENOGRAPHER_CONFIG environmental variable to point to your stenographer config if it's in a nonstandard place (defaults to /etc/stenographer/config).
11 September 2020 stenographer 1.0.1