NaCl(1) General Commands Manual NaCl(1)NAME
CurveCP -- Message-handling programs
SYNOPSIS
curvecpmessage [-q (optional)] [-Q (optional)] [-v (optional)] [-c (optional)] [-C (optional)] [-s (optional)] [prog]
DESCRIPTION
This manual page documents briefly the CurveCP commands.
A traditional UNIX-style server such as ftpd handles just one network connection, reading input from stdin and writing output to stdout. A
"superserver" such as inetd or tcpserver listens for network connections and starts a separate server process for each connection.
The CurveCP command-line tools have an extra level of modularity. The curvecpserver superserver listens for network connections. For each
connection, curvecpserver starts the curvecpmessage message handler; curvecpmessage then starts a server such as ftpd. Then ftpd sends a
stream of data to curvecpmessage, which in turn sends messages to curvecpserver, which encrypts and authenticates the messages and sends
them inside network packets. At the same time curvecpclient receives network packets, verifies and decrypts messages inside the packets,
and passes the messages to curvecpmessage; curvecpmessage sends a stream of data to ftpd. The same curvecpmessage tool is also used by
curvecpclient.
curvecpserver and curvecpclient can use programs other than curvecpmessage. Those programs can directly generate messages in the CurveCP
message format without talking to separate tools such as ftpd; or they can support a completely different protocol that reuses CurveCP's
cryptographic layer but transmits different kinds of messages.
OPTIONS
How to use curvecpmessage:
-q optional
no error messages
-Q optional
print error messages (default)
-v optional
print extra information
-c optional
program is a client; server starts first
-C optional
program is a client that starts first
-s optional
program is a server (default)
prog run this server
SEE ALSO
curvecpserver (1), curvecpclient (1), inetd (8), tcpserver (1).
AUTHOR
This manual page was written by Sergiusz Pawlowicz debian@pawlowicz.name for the Debian system (and may be used by others). The source of
this page is a webpage http://curvecp.org/messageapi.html . Permission is granted to copy, distribute and/or modify this document under
public domain.
This manual page was rewritten for the Debian distribution because the original program does not have a manual page.
NaCl(1)
Check Out this Related Man Page
tcpserver(1) General Commands Manual tcpserver(1)NAME
tcpserver - accept incoming TCP connections
SYNOPSIS
tcpserver [ -146jpPhHrRoOdDqQv ] [ -climit ] [ -xrules.cdb ] [ -Bbanner ] [ -ggid ] [ -uuid ] [ -bbacklog ] [ -llocalname ] [ -ttimeout ] [
-Iinterface ] host port program [ arg ... ]
DESCRIPTION
tcpserver waits for connections from TCP clients. For each connection, it runs program with the given arguments, with descriptor 0 reading
from the network and descriptor 1 writing to the network.
The server's address is given by host and port. host can be 0, allowing connections from any host; or a particular IP address, allowing
connections only to that address; or a host name, allowing connections to the first IP address for that host. port may be a numeric port
number or a port name. If port is 0, tcpserver will choose a free port.
tcpserver sets up several environment variables, as described in tcp-environ(5).
tcpserver exits when it receives SIGTERM.
OPTIONS -climit
Do not handle more than limit simultaneous connections. If there are limit simultaneous copies of program running, defer acceptance
of a new connection until one copy finishes. limit must be a positive integer. Default: 40.
-xrules.cdb
Follow the rules compiled into rules.cdb by tcprules. These rules may specify setting environment variables or rejecting connec-
tions from bad sources.
tcpserver does not read rules.cdb into memory; you can rerun tcprules to change tcpserver's behavior on the fly.
-Bbanner
Write banner to the network immediately after each connection is made. tcpserver writes banner before looking up TCPREMOTEHOST,
before looking up TCPREMOTEINFO, and before checking rules.cdb.
This feature can be used to reduce latency in protocols where the client waits for a greeting from the server.
-ggid Switch group ID to gid after preparing to receive connections. gid must be a positive integer.
-uuid Switch user ID to uid after preparing to receive connections. uid must be a positive integer.
-1 After preparing to receive connections, print the local port number to standard output.
-4 Fall back to IPv4 sockets. This is necessary for terminally broken systems like OpenBSD which will not let IPv6 sockets connect to
V4-mapped IPv6 addresses. Please note that this also applies to DNS lookups, so you will have to use an DNS resolver with an IPv6
address to accept IPv6 connections. Use DNSCACHEIP to set the DNS resolver IP dynamically.
-6 Force IPv6 mode in UCSPI environment variables, even for IPv4 connections. This will set $PROTO to TCP6 and put IPv4-mapped IPv6
addresses in TCPLOCALIP and TCPREMOTEIP.
-Iinterface
Bind to the network interface interface ("eth0" on Linux, for example). This is only defined and needed for IPv6 link-local
addresses.
-bbacklog
Allow up to backlog simultaneous SYN_RECEIVEDs. Default: 20. On some systems, backlog is silently limited to 5. See listen(2) for
more details.
-o Leave IP options alone. If the client is sending packets along an IP source route, send packets back along the same route.
-O (Default.) Kill IP options. A client can still use source routing to connect and to send data, but packets will be sent back along
the default route.
-d (Default.) Delay sending data for a fraction of a second whenever the remote host is responding slowly, to make better use of the
network.
-D Never delay sending data; enable TCP_NODELAY. This is appropriate for interactive connections.
-q Quiet. Do not print any messages.
-Q (Default.) Print error messages.
-v Verbose. Print all available messages.
DATA-GATHERING OPTIONS-p Paranoid. After looking up the remote host name, look up the IP addresses for that name, and make sure one of them matches TCPRE-
MOTEIP. If none of them do, unset TCPREMOTEHOST.
-P (Default.) Not paranoid.
-h (Default.) Look up the remote host name and set TCPREMOTEHOST.
-H Do not look up the remote host name.
-llocalname
Do not look up the local host name; use localname for TCPLOCALHOST.
-r (Default.) Attempt to obtain TCPREMOTEINFO from the remote host.
-R Do not attempt to obtain TCPREMOTEINFO from the remote host.
-ttimeout
Give up on the TCPREMOTEINFO connection attempt after timeout seconds. Default: 26.
SEE ALSO argv0(1), fixcr(1), recordio(1), tcpclient(1), tcprules(1), listen(2), tcp-environ(5)tcpserver(1)