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14b84a7f07
There are setups where no host interface is available or configured at all, intentionally or not, temporarily or not, but users expect (Podman) containers to run in any case as they did with slirp4netns, and we're now getting reports that we broke such setups at a rather alarming rate. To this end, if we don't find any usable host interface, instead of exiting: - for IPv4, use 169.254.2.1 as guest/container address and 169.254.2.2 as default gateway - for IPv6, don't assign any address (forcibly disable DHCPv6), and use the *first* link-local address we observe to represent the guest/container. Advertise fe80::1 as default gateway - use 'tap0' as default interface name for pasta Change ifi4 and ifi6 in struct ctx to int and accept a special -1 value meaning that no host interface was selected, but the IP family is enabled. The fact that the kernel uses unsigned int values for those is not an issue as 1. one can't create so many interfaces anyway and 2. we otherwise handle those values transparently. Fix a botched conditional in conf_print() to actually skip printing DHCPv6 information if DHCPv6 is disabled (and skip printing NDP information if NDP is disabled). Link: https://github.com/containers/podman/issues/24614 Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
1090 lines
40 KiB
Groff
1090 lines
40 KiB
Groff
.\" SPDX-License-Identifier: GPL-2.0-or-later
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.\" Copyright (c) 2020-2022 Red Hat GmbH
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.\" Author: Stefano Brivio <sbrivio@redhat.com>
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.TH passt 1
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.SH NAME
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.B passt
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\- Unprivileged user-mode network connectivity for virtual machines
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.br
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.B pasta
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\- Unprivileged user-mode network connectivity for network namespaces
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.SH SYNOPSIS
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.B passt
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[\fIOPTION\fR]...
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.br
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.B pasta
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[\fIOPTION\fR]... [\fICOMMAND\fR [\fIARG\fR]...]
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.br
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.B pasta
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[\fIOPTION\fR]... \fIPID\fR
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.br
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.B pasta
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[\fIOPTION\fR]... \fB--netns\fR [\fIPATH\fR|\fINAME\fR]
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.SH DESCRIPTION
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.SS passt
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.B passt
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(\fIP\fRlug \fIA\fR \fIS\fRimple \fIS\fRocket \fIT\fRransport) provides full,
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quasi-native network connectivity to virtual machines in user-mode without
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requiring any capabilities or privileges.
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The data plane implements a translation layer between a Layer-2 virtual network
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interface and native Layer-4 (TCP, UDP, ping) sockets on the host, giving the
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illusion that application processes residing on the guest are running on the
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local host, from a networking perspective.
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Built-in ARP, DHCP, NDP, and DHCPv6 implementations are designed to provide the
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guest with a network configuration that tightly resembles the host native
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configuration. With the default options, guest and host share IP addresses,
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routes, and port bindings.
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Port forwarding and translation allow networking services running in the guest
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to be reachable from both local and remote hosts.
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Unlike \fBslirp4netns\fR(1), \fBpasst\fR doesn't implement a full TCP stack: the
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TCP translation layer has no stateful data buffering and operates by reflecting
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one peer's observed parameters (congestion window size, acknowledged data, etc.)
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to the corresponding peer.
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Currently, the only supported hypervisor is \fBqemu\fR(1), connecting to
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\fBpasst\fR by means of a UNIX domain socket. This is supported starting from
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qemu 7.2. For older qemu versions, see the \fBqrap\fR(1) wrapper.
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.SS pasta
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.B pasta
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(\fIP\fRack \fIA\fR \fIS\fRubtle \fIT\fRap \fIA\fRbstraction) provides
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equivalent functionality to network namespaces, as the one offered by
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\fBpasst\fR for virtual machines.
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If PID or --netns are given, \fBpasta\fR associates to an existing
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user and network namespace. Otherwise, \fBpasta\fR creates a new user
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and network namespace, and spawns the given command or a default shell
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within this context. A \fItap\fR device within the network namespace
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is created to provide network connectivity.
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For local TCP and UDP traffic only, \fBpasta\fR also implements a bypass path
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directly mapping Layer-4 sockets between \fIinit\fR and target namespaces,
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for performance reasons.
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.SH OPTIONS
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Unless otherwise noted below, \fBif conflicting or multiple options are given,
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the last one takes effect.\fR
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.TP
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.BR \-d ", " \-\-debug
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Be verbose, don't log to the system logger.
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.TP
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.BR \-\-trace
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Be extra verbose, show single packets. Implies \fB--debug\fR.
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.TP
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.BR \-q ", " \-\-quiet
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Don't print informational messages.
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.TP
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.BR \-f ", " \-\-foreground
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Don't run in background. This implies that the process is not moved to a
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detached PID namespace after starting, because the PID itself cannot change.
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Default is to fork into background.
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.TP
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.BR \-e ", " \-\-stderr " " (DEPRECATED)
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This option has no effect, and is maintained for compatibility purposes only.
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Note that this configuration option is \fBdeprecated\fR and will be removed in a
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future version.
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.TP
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.BR \-l ", " \-\-log-file " " \fIPATH\fR
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Log to file \fIPATH\fR, and not to the system logger.
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Specifying this option multiple times does \fInot\fR lead to multiple log files:
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the last given option takes effect.
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.TP
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.BR \-\-log-size " " \fISIZE\fR
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Limit log file size to \fISIZE\fR bytes. When the log file is full, make room
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for new entries by removing old ones at the beginning. This limit is mandatory.
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Default is 1048576 (1 MiB).
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.TP
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.BR \-\-runas " " \fIUID\fR|\fIUID:GID\fR|\fILOGIN\fR|\fILOGIN:GROUP\fR
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Attempt to change to given UID and corresponding group if UID is given,
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or to given UID and given GID if both are given. Alternatively, login name, or
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login name and group name can be passed. This requires privileges (either
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initial effective UID 0 or CAP_SETUID capability) to work.
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Default is to change to user \fInobody\fR if started as root.
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.TP
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.BR \-h ", " \-\-help
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Display a help message and exit.
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.TP
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.BR \-\-version
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Show version and exit.
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.TP
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.BR \-p ", " \-\-pcap " " \fIfile
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Capture tap-facing (that is, guest-side or namespace-side) network packets to
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\fIfile\fR in \fBpcap\fR format.
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Specifying this option multiple times does \fInot\fR lead to multiple capture
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files: the last given option takes effect.
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.TP
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.BR \-P ", " \-\-pid " " \fIfile
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Write own PID to \fIfile\fR once initialisation is done, before forking to
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background (if configured to do so).
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.TP
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.BR \-m ", " \-\-mtu " " \fImtu
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Assign \fImtu\fR via DHCP (option 26) and NDP (option type 5). A zero value
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disables assignment.
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By default, the advertised MTU is 65520 bytes, that is, the maximum 802.3 MTU
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minus the length of a 802.3 header, rounded to 32 bits (IPv4 words).
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.TP
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.BR \-a ", " \-\-address " " \fIaddr
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Assign IPv4 \fIaddr\fR via DHCP (\fByiaddr\fR), or \fIaddr\fR via DHCPv6 (option
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5) and an \fIaddr\fR-based prefix via NDP Router Advertisement (option type 3)
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for an IPv6 \fIaddr\fR.
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This option can be specified zero (for defaults) to two times (once for IPv4,
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once for IPv6).
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By default, assigned IPv4 and IPv6 addresses are taken from the host interfaces
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with the first default route, if any, for the corresponding IP version. If no
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default routes are available and there is any interface with any route for a
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given IP version, the first of these interfaces will be chosen instead. If no
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such interface exists, the link-local address 169.254.2.1 is assigned for IPv4,
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and no additional address will be assigned for IPv6.
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.TP
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.BR \-n ", " \-\-netmask " " \fImask
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Assign IPv4 netmask \fImask\fR, expressed as dot-decimal or number of bits, via
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DHCP (option 1).
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By default, the netmask associated to the host address matching the assigned one
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is used. If there's no matching address on the host, the netmask is determined
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according to the CIDR block of the assigned address (RFC 4632).
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.TP
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.BR \-M ", " \-\-mac-addr " " \fIaddr
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Use source MAC address \fIaddr\fR when communicating to the guest or to the
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target namespace.
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Default is the locally administered MAC addresses 9a:55:9a:55:9a:55.
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.TP
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.BR \-g ", " \-\-gateway " " \fIaddr
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Assign IPv4 \fIaddr\fR as default gateway via DHCP (option 3), or IPv6
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\fIaddr\fR as source for NDP Router Advertisement and DHCPv6 messages.
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This option can be specified zero (for defaults) to two times (once for IPv4,
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once for IPv6).
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By default, IPv4 and IPv6 gateways are taken from the host interface with the
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first default route, if any, for the corresponding IP version. If the default
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route is a multipath one, the gateway is the first nexthop router returned by
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the kernel which has the highest weight in the set of paths. If no default
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routes are available and there is just one interface with any route, that
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interface will be chosen instead. If no such interface exists, the link-local
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address 169.254.2.2 is used for IPv4, and the link-local address fe80::1 is used
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for IPv6.
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Note: these addresses are also used as source address for packets directed to
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the guest or to the target namespace having a loopback or local source address,
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to allow mapping of local traffic to guest and target namespace. See the
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\fBNOTES\fR below for more details about this mechanism.
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.TP
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.BR \-i ", " \-\-interface " " \fIname
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Use host interface \fIname\fR to derive addresses and routes.
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Default is to use the interfaces specified by \fB--outbound-if4\fR and
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\fB--outbound-if6\fR, for IPv4 and IPv6 addresses and routes, respectively.
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If no interfaces are given, the interface with the first default routes for each
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IP version is selected. If no default routes are available and there is just one
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interface with any route, that interface will be chosen instead. If no such
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interface exists, host interfaces will be ignored for the purposes of assigning
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addresses and routes, and link-local addresses will be used instead.
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.TP
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.BR \-o ", " \-\-outbound " " \fIaddr
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Use an IPv4 \fIaddr\fR as source address for IPv4 outbound TCP connections, UDP
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flows, ICMP requests, or an IPv6 \fIaddr\fR for IPv6 ones, by binding outbound
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sockets to it.
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This option can be specified zero (for defaults) to two times (once for IPv4,
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once for IPv6).
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By default, the source address is selected by the routing tables.
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.TP
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.BR \-\-outbound-if4 " " \fIname
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Bind IPv4 outbound sockets to host interface \fIname\fR, and, unless another
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interface is specified via \fB-i\fR, \fB--interface\fR, use this interface to
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derive IPv4 addresses and routes.
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By default, the interface given by the default route is selected. If no default
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routes are available and there is just one interface with any route, that
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interface will be chosen instead. If no such interface exists, outbound sockets
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will not be bound to any specific interface.
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.TP
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.BR \-\-outbound-if6 " " \fIname
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Bind IPv6 outbound sockets to host interface \fIname\fR, and, unless another
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interface is specified via \fB-i\fR, \fB--interface\fR, use this interface to
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derive IPv6 addresses and routes.
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By default, the interface given by the default route is selected. If no default
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routes are available and there is just one interface with any route, that
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interface will be chosen instead. If no such interface exists, outbound sockets
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will not be bound to any specific interface.
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.TP
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.BR \-D ", " \-\-dns " " \fIaddr
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Instruct the guest (via DHCP, DHVPv6 or NDP) to use \fIaddr\fR (IPv4
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or IPv6) as a nameserver, as configured (see options
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\fB--no-dhcp-dns\fR, \fB--dhcp-dns\fR) instead of reading addresses
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from \fI/etc/resolv.conf\fR. This option can be specified multiple
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times. Specifying \fB-D none\fR disables usage of DNS addresses
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altogether. Unlike addresses from \fI/etc/resolv.conf\fR, \fIaddr\fR
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is given to the guest without remapping. For example \fB--dns
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127.0.0.1\fR will instruct the guest to use itself as nameserver, not
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the host.
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.TP
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.BR \-\-dns-forward " " \fIaddr
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Map \fIaddr\fR (IPv4 or IPv6) as seen from guest or namespace to the
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nameserver (with corresponding IP version) specified by the
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\fB\-\-dns-host\fR option. Maps only UDP and TCP traffic to port 53 or
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port 853. Replies are translated back with a reverse mapping. This
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option can be specified zero to two times (once for IPv4, once for
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IPv6).
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.TP
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.BR \-\-dns-host " " \fIaddr
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Configure the host nameserver which guest or namespace queries to the
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\fB\-\-dns-forward\fR address will be redirected to. This option can
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be specified zero to two times (once for IPv4, once for IPv6).
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By default, the first nameserver from the host's
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\fI/etc/resolv.conf\fR.
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.TP
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.BR \-S ", " \-\-search " " \fIlist
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Use space-separated \fIlist\fR for DHCP, DHCPv6, and NDP purposes, instead of
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reading entries from \fI/etc/resolv.conf\fR. See options \fB--no-dhcp-search\fR
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and \fB--dhcp-search\fR. \fB--search none\fR disables the DNS domain search
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list altogether (if you need to search a domain called "none" you can use
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\fB--search none.\fR).
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.TP
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.BR \-\-no-dhcp-dns
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In \fIpasst\fR mode, do not assign IPv4 addresses via DHCP (option 23) or IPv6
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addresses via NDP Router Advertisement (option type 25) and DHCPv6 (option 23)
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as DNS resolvers.
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By default, all the configured addresses are passed.
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.TP
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.BR \-\-dhcp-dns
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In \fIpasta\fR mode, assign IPv4 addresses via DHCP (option 23) or IPv6
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addresses via NDP Router Advertisement (option type 25) and DHCPv6 (option 23)
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as DNS resolvers.
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By default, configured addresses, if any, are not passed.
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.TP
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.BR \-\-no-dhcp-search
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In \fIpasst\fR mode, do not send the DNS domain search list addresses via DHCP
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(option 119), via NDP Router Advertisement (option type 31) and DHCPv6 (option
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24).
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By default, the DNS domain search list resulting from configuration is passed.
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.TP
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.BR \-\-dhcp-search
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In \fIpasta\fR mode, send the DNS domain search list addresses via DHCP (option
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119), via NDP Router Advertisement (option type 31) and DHCPv6 (option 24).
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By default, the DNS domain search list resulting from configuration is not
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passed.
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.TP
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.BR \-\-no-tcp
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Disable the TCP protocol handler. No TCP connections will be accepted host-side,
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and TCP packets coming from guest or target namespace will be silently dropped.
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.TP
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.BR \-\-no-udp
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Disable the UDP protocol handler. No UDP traffic coming from the host side will
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be forwarded, and UDP packets coming from guest or target namespace will be
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silently dropped.
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.TP
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.BR \-\-no-icmp
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Disable the ICMP/ICMPv6 echo handler. ICMP and ICMPv6 echo requests coming from
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guest or target namespace will be silently dropped.
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.TP
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.BR \-\-no-dhcp
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Disable the DHCP server. DHCP client requests coming from guest or target
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namespace will be silently dropped. Implied if there is no gateway on the
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selected IPv4 default route.
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.TP
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.BR \-\-no-ndp
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Disable NDP responses. NDP messages coming from guest or target namespace will
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be ignored.
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.TP
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.BR \-\-no-dhcpv6
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Disable the DHCPv6 server. DHCPv6 client requests coming from guest or target
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namespace will be silently dropped.
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.TP
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.BR \-\-no-ra
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Disable Router Advertisements. Router Solicitations coming from guest or target
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namespace will be ignored.
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.TP
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.BR \-\-freebind
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Allow any binding address to be specified for \fB-t\fR and \fB-u\fR
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options. Usually binding addresses must be addresses currently
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configured on the host. With \fB\-\-freebind\fR, the
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\fBIP_FREEBIND\fR or \fBIPV6_FREEBIND\fR socket option is enabled
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allowing any address to be used. This is typically used to bind
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addresses which might be configured on the host in future, at which
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point the forwarding will immediately start operating.
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.TP
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.BR \-\-map-host-loopback " " \fIaddr
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Translate \fIaddr\fR to refer to the host. Packets from the guest to
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\fIaddr\fR will be redirected to the host. On the host such packets
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will appear to have both source and destination of 127.0.0.1 or ::1.
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If \fIaddr\fR is 'none', no address is mapped (this implies
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\fB--no-map-gw\fR). Only one IPv4 and one IPv6 address can be
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translated, if the option is specified multiple times, the last one
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takes effect.
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Default is to translate the guest's default gateway address, unless
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\fB--no-map-gw\fR is given, in which case no address is mapped.
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.TP
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.BR \-\-no-map-gw
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Don't remap TCP connections and untracked UDP traffic, with the gateway address
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as destination, to the host. Implied if there is no gateway on the selected
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default route, or if there is no default route, for any of the enabled address
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families.
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.TP
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.BR \-\-map-guest-addr " " \fIaddr
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Translate \fIaddr\fR in the guest to be equal to the guest's assigned
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address on the host. That is, packets from the guest to \fIaddr\fR
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will be redirected to the address assigned to the guest with \fB-a\fR,
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or by default the host's global address. This allows the guest to
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access services available on the host's global address, even though its
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own address shadows that of the host.
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If \fIaddr\fR is 'none', no address is mapped. Only one IPv4 and one
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IPv6 address can be translated, and if the option is specified
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multiple times, the last one for each address type takes effect.
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By default, mapping happens as described for the \-\-map-host-loopback option.
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.TP
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.BR \-4 ", " \-\-ipv4-only
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Enable IPv4-only operation. IPv6 traffic will be ignored.
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By default, IPv6 operation is enabled as long as at least an IPv6 route and an
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interface address are configured on a given host interface.
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.TP
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.BR \-6 ", " \-\-ipv6-only
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Enable IPv6-only operation. IPv4 traffic will be ignored.
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By default, IPv4 operation is enabled as long as at least an IPv4 route and an
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interface address are configured on a given host interface.
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.SS \fBpasst\fR-only options
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.TP
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.BR \-s ", " \-\-socket " " \fIpath
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Path for UNIX domain socket used by \fBqemu\fR(1) or \fBqrap\fR(1) to connect to
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\fBpasst\fR.
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Default is to probe a free socket, not accepting connections, starting from
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\fI/tmp/passt_1.socket\fR to \fI/tmp/passt_64.socket\fR.
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.TP
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.BR \-F ", " \-\-fd " " \fIFD
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Pass a pre-opened, connected socket to \fBpasst\fR. Usually the socket is opened
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in the parent process and \fBpasst\fR inherits it when run as a child. This
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allows the parent process to open sockets using another address family or
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requiring special privileges.
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This option implies the behaviour described for \-\-one-off, once this socket
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is closed.
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.TP
|
|
.BR \-1 ", " \-\-one-off
|
|
Quit after handling a single client connection, that is, once the client closes
|
|
the socket, or once we get a socket error.
|
|
|
|
.TP
|
|
.BR \-t ", " \-\-tcp-ports " " \fIspec
|
|
Configure TCP port forwarding to guest. \fIspec\fR can be one of:
|
|
.RS
|
|
|
|
.TP
|
|
.BR none
|
|
Don't forward any ports
|
|
|
|
.TP
|
|
.BR all
|
|
Forward all unbound, non-ephemeral ports, as permitted by current capabilities.
|
|
For low (< 1024) ports, see \fBNOTES\fR. No failures are reported for
|
|
unavailable ports, unless no ports could be forwarded at all.
|
|
|
|
.TP
|
|
.BR ports
|
|
A comma-separated list of ports, optionally ranged with \fI-\fR, and,
|
|
optionally, with target ports after \fI:\fR, if they differ. Specific addresses
|
|
can be bound as well, separated by \fI/\fR, and also, since Linux 5.7, limited
|
|
to specific interfaces, prefixed by \fI%\fR. Within given ranges, selected ports
|
|
and ranges can be excluded by an additional specification prefixed by \fI~\fR.
|
|
|
|
Specifying excluded ranges only implies that all other ports are forwarded. In
|
|
this case, no failures are reported for unavailable ports, unless no ports could
|
|
be forwarded at all.
|
|
|
|
Examples:
|
|
.RS
|
|
.TP
|
|
-t 22
|
|
Forward local port 22 to port 22 on the guest
|
|
.TP
|
|
-t 22:23
|
|
Forward local port 22 to port 23 on the guest
|
|
.TP
|
|
-t 22,25
|
|
Forward local ports 22 and 25 to ports 22 and 25 on the guest
|
|
.TP
|
|
-t 22-80
|
|
Forward local ports between 22 and 80 to corresponding ports on the guest
|
|
.TP
|
|
-t 22-80:32-90
|
|
Forward local ports between 22 and 80 to ports between 32 and 90 on the guest
|
|
.TP
|
|
-t 192.0.2.1/22
|
|
Forward local port 22, bound to 192.0.2.1, to port 22 on the guest
|
|
.TP
|
|
-t 192.0.2.1%eth0/22
|
|
Forward local port 22, bound to 192.0.2.1 and interface eth0, to port 22
|
|
.TP
|
|
-t %eth0/22
|
|
Forward local port 22, bound to any address on interface eth0, to port 22
|
|
.TP
|
|
-t 2000-5000,~3000-3010
|
|
Forward local ports between 2000 and 5000, except for those between 3000 and
|
|
3010
|
|
.TP
|
|
-t 192.0.2.1/20-30,~25
|
|
For the local address 192.0.2.1, forward ports between 20 and 24 and between 26
|
|
and 30
|
|
.TP
|
|
-t ~20000-20010
|
|
Forward all ports to the guest, except for the range from 20000 to 20010
|
|
.RE
|
|
|
|
Default is \fBnone\fR.
|
|
.RE
|
|
|
|
.TP
|
|
.BR \-u ", " \-\-udp-ports " " \fIspec
|
|
Configure UDP port forwarding to guest. \fIspec\fR is as described for TCP
|
|
above.
|
|
|
|
Note: unless overridden, UDP ports with numbers corresponding to forwarded TCP
|
|
port numbers are forwarded too, without, however, any port translation. IPv6
|
|
bound ports are also forwarded for IPv4.
|
|
|
|
Default is \fBnone\fR.
|
|
|
|
.SS \fBpasta\fR-only options
|
|
|
|
.TP
|
|
.BR \-I ", " \-\-ns-ifname " " \fIname
|
|
Name of tap interface to be created in target namespace.
|
|
By default, the same interface name as the external, routable interface is used.
|
|
If no such interface exists, the name \fItap0\fR will be used instead.
|
|
|
|
.TP
|
|
.BR \-t ", " \-\-tcp-ports " " \fIspec
|
|
Configure TCP port forwarding to namespace. \fIspec\fR can be one of:
|
|
.RS
|
|
|
|
.TP
|
|
.BR none
|
|
Don't forward any ports
|
|
|
|
.TP
|
|
.BR auto
|
|
Dynamically forward ports bound in the namespace. The list of ports is
|
|
periodically derived (every second) from listening sockets reported by
|
|
\fI/proc/net/tcp\fR and \fI/proc/net/tcp6\fR, see \fBproc\fR(5).
|
|
|
|
.TP
|
|
.BR ports
|
|
A comma-separated list of ports, optionally ranged with \fI-\fR, and,
|
|
optionally, with target ports after \fI:\fR, if they differ. Specific addresses
|
|
can be bound as well, separated by \fI/\fR, and also, since Linux 5.7, limited
|
|
to specific interfaces, prefixed by \fI%\fR. Within given ranges, selected ports
|
|
and ranges can be excluded by an additional specification prefixed by \fI~\fR.
|
|
|
|
Specifying excluded ranges only implies that all other ports are forwarded. In
|
|
this case, no failures are reported for unavailable ports, unless no ports could
|
|
be forwarded at all.
|
|
|
|
Examples:
|
|
.RS
|
|
.TP
|
|
-t 22
|
|
Forward local port 22 to 22 in the target namespace
|
|
.TP
|
|
-t 22:23
|
|
Forward local port 22 to port 23 in the target namespace
|
|
.TP
|
|
-t 22,25
|
|
Forward local ports 22 and 25 to ports 22 and 25 in the target namespace
|
|
.TP
|
|
-t 22-80
|
|
Forward local ports between 22 and 80 to corresponding ports in the target
|
|
namespace
|
|
.TP
|
|
-t 22-80:32-90
|
|
Forward local ports between 22 and 80 to ports between 32 and 90 in the target
|
|
namespace
|
|
.TP
|
|
-t 192.0.2.1/22
|
|
Forward local port 22, bound to 192.0.2.1, to port 22 in the target namespace
|
|
.TP
|
|
-t 192.0.2.1%eth0/22
|
|
Forward local port 22, bound to 192.0.2.1 and interface eth0, to port 22
|
|
.TP
|
|
-t %eth0/22
|
|
Forward local port 22, bound to any address on interface eth0, to port 22
|
|
.TP
|
|
-t 2000-5000,~3000-3010
|
|
Forward local ports between 2000 and 5000, except for those between 3000 and
|
|
3010
|
|
.TP
|
|
-t 192.0.2.1/20-30,~25
|
|
For the local address 192.0.2.1, forward ports between 20 and 24 and between 26
|
|
and 30
|
|
.TP
|
|
-t ~20000-20010
|
|
Forward all ports to the namespace, except for those between 20000 and 20010
|
|
.RE
|
|
|
|
IPv6 bound ports are also forwarded for IPv4.
|
|
|
|
Default is \fBauto\fR.
|
|
.RE
|
|
|
|
.TP
|
|
.BR \-u ", " \-\-udp-ports " " \fIspec
|
|
Configure UDP port forwarding to namespace. \fIspec\fR is as described for TCP
|
|
above, and the list of ports is derived from listening sockets reported by
|
|
\fI/proc/net/udp\fR and \fI/proc/net/udp6\fR, see \fBproc\fR(5).
|
|
|
|
Note: unless overridden, UDP ports with numbers corresponding to forwarded TCP
|
|
port numbers are forwarded too, without, however, any port translation.
|
|
|
|
IPv6 bound ports are also forwarded for IPv4.
|
|
|
|
Default is \fBauto\fR.
|
|
|
|
.TP
|
|
.BR \-T ", " \-\-tcp-ns " " \fIspec
|
|
Configure TCP port forwarding from target namespace to init namespace.
|
|
\fIspec\fR is as described above for TCP.
|
|
|
|
Default is \fBauto\fR.
|
|
|
|
.TP
|
|
.BR \-U ", " \-\-udp-ns " " \fIspec
|
|
Configure UDP port forwarding from target namespace to init namespace.
|
|
\fIspec\fR is as described above for UDP.
|
|
|
|
Default is \fBauto\fR.
|
|
|
|
.TP
|
|
.BR \-\-host-lo-to-ns-lo " " (DEPRECATED)
|
|
If specified, connections forwarded with \fB\-t\fR and \fB\-u\fR from
|
|
the host's loopback address will appear on the loopback address in the
|
|
guest as well. Without this option such forwarded packets will appear
|
|
to come from the guest's public address.
|
|
|
|
.TP
|
|
.BR \-\-userns " " \fIspec
|
|
Target user namespace to join, as a path. If PID is given, without this option,
|
|
the user namespace will be the one of the corresponding process.
|
|
|
|
.TP
|
|
.BR \-\-netns " " \fIspec
|
|
Target network namespace to join, as a path or a name. A name is treated as
|
|
with \fBip-netns(8)\fR as equivalent to a path in \fI/run/netns\fR.
|
|
|
|
This option can't be specified with a PID.
|
|
|
|
.TP
|
|
.BR \-\-netns-only
|
|
Join only a target network namespace, not a user namespace, and don't create one
|
|
for sandboxing purposes either. This is implied if PATH or NAME are given
|
|
without \-\-userns.
|
|
|
|
.TP
|
|
.BR \-\-no-netns-quit
|
|
Do not exit once the target namespace reference is removed.
|
|
|
|
Without this option, \fBpasta\fR will terminate if the target network namespace
|
|
is bound to the filesystem, and the given path is deleted, or if the target
|
|
network namespace is represented by a procfs entry, and that entry is deleted,
|
|
representing the fact that a process with the given PID terminated.
|
|
|
|
.TP
|
|
.BR \-\-config-net
|
|
Configure networking in the namespace: set up addresses and routes as configured
|
|
or sourced from the host, and bring up the tap interface.
|
|
|
|
.TP
|
|
.BR \-\-no-copy-routes " " (DEPRECATED)
|
|
With \-\-config-net, do not copy all the routes associated to the interface we
|
|
derive addresses and routes from: set up only the default gateway. Implied by
|
|
-g, \-\-gateway, for the corresponding IP version only.
|
|
|
|
Default is to copy all the routing entries from the interface in the outer
|
|
namespace to the target namespace, translating the output interface attribute to
|
|
the outbound interface in the namespace.
|
|
|
|
Note that this configuration option is \fBdeprecated\fR and will be removed in a
|
|
future version. It is not expected to be of any use, and it simply reflects a
|
|
legacy behaviour. If you have any use for this, refer to \fBREPORTING BUGS\fR
|
|
below.
|
|
|
|
.TP
|
|
.BR \-\-no-copy-addrs " " (DEPRECATED)
|
|
With \-\-config-net, do not copy all the addresses associated to the interface
|
|
we derive addresses and routes from: set up a single one. Implied by \-a,
|
|
\-\-address, for the corresponding IP version only.
|
|
|
|
Default is to copy all the addresses, except for link-local ones, from the
|
|
interface from the outer namespace to the target namespace.
|
|
|
|
Note that this configuration option is \fBdeprecated\fR and will be removed in a
|
|
future version. It is not expected to be of any use, and it simply reflects a
|
|
legacy behaviour. If you have any use for this, refer to \fBREPORTING BUGS\fR
|
|
below.
|
|
|
|
.TP
|
|
.BR \-\-ns-mac-addr " " \fIaddr
|
|
Configure MAC address \fIaddr\fR on the tap interface in the namespace.
|
|
|
|
Default is to let the tap driver build a pseudorandom hardware address.
|
|
|
|
.SH EXAMPLES
|
|
|
|
.SS \fBpasta
|
|
.BR "Create and use a new, connected, user and network namespace"
|
|
.RS
|
|
.nf
|
|
$ iperf3 -s -D
|
|
$ ./pasta
|
|
Outbound interface: eth0, namespace interface: eth0
|
|
ARP:
|
|
address: 28:16:ad:39:a9:ea
|
|
DHCP:
|
|
assign: 192.168.1.118
|
|
mask: 255.255.255.0
|
|
router: 192.168.1.1
|
|
NDP/DHCPv6:
|
|
assign: 2a02:6d40:3ca5:2001:b81d:fa4a:8cdd:cf17
|
|
router: fe80::62e3:27ff:fe33:2b01
|
|
#
|
|
# dhclient -4 --no-pid
|
|
# dhclient -6 --no-pid
|
|
# ip address show
|
|
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
|
|
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
|
|
inet 127.0.0.1/8 scope host lo
|
|
valid_lft forever preferred_lft forever
|
|
inet6 ::1/128 scope host
|
|
valid_lft forever preferred_lft forever
|
|
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 65520 qdisc pfifo_fast state UNKNOWN group default qlen 1000
|
|
link/ether 5e:90:02:eb:b0:2a brd ff:ff:ff:ff:ff:ff
|
|
inet 192.168.1.118/24 brd 192.168.1.255 scope global eth0
|
|
valid_lft forever preferred_lft forever
|
|
inet6 2a02:6d40:3ca5:2001:b81d:fa4a:8cdd:cf17/128 scope global
|
|
valid_lft forever preferred_lft forever
|
|
inet6 2a02:6d40:3ca5:2001:5c90:2ff:feeb:b02a/64 scope global dynamic mngtmpaddr
|
|
valid_lft 3591sec preferred_lft 3591sec
|
|
inet6 fe80::5c90:2ff:feeb:b02a/64 scope link
|
|
valid_lft forever preferred_lft forever
|
|
# ip route show
|
|
default via 192.168.1.1 dev eth0
|
|
192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.118
|
|
# ip -6 route show
|
|
2a02:6d40:3ca5:2001:b81d:fa4a:8cdd:cf17 dev eth0 proto kernel metric 256 pref medium
|
|
2a02:6d40:3ca5:2001::/64 dev eth0 proto kernel metric 256 expires 3584sec pref medium
|
|
fe80::/64 dev eth0 proto kernel metric 256 pref medium
|
|
default via fe80::62e3:27ff:fe33:2b01 dev eth0 proto ra metric 1024 expires 3584sec pref medium
|
|
# iperf3 -c 127.0.0.1 -t1
|
|
Connecting to host 127.0.0.1, port 5201
|
|
[ 5] local 127.0.0.1 port 51938 connected to 127.0.0.1 port 5201
|
|
[ ID] Interval Transfer Bitrate Retr Cwnd
|
|
[ 5] 0.00-1.00 sec 4.46 GBytes 38.3 Gbits/sec 0 3.93 MBytes
|
|
- - - - - - - - - - - - - - - - - - - - - - - - -
|
|
[ ID] Interval Transfer Bitrate Retr
|
|
[ 5] 0.00-1.00 sec 4.46 GBytes 38.3 Gbits/sec 0 sender
|
|
[ 5] 0.00-1.41 sec 4.45 GBytes 27.1 Gbits/sec receiver
|
|
|
|
iperf Done.
|
|
# iperf3 -c ::1 -t1
|
|
Connecting to host ::1, port 5201
|
|
[ 5] local ::1 port 50108 connected to ::1 port 5201
|
|
[ ID] Interval Transfer Bitrate Retr Cwnd
|
|
[ 5] 0.00-1.00 sec 4.35 GBytes 37.4 Gbits/sec 0 4.99 MBytes
|
|
- - - - - - - - - - - - - - - - - - - - - - - - -
|
|
[ ID] Interval Transfer Bitrate Retr
|
|
[ 5] 0.00-1.00 sec 4.35 GBytes 37.4 Gbits/sec 0 sender
|
|
[ 5] 0.00-1.41 sec 4.35 GBytes 26.4 Gbits/sec receiver
|
|
|
|
iperf Done.
|
|
# ping -c1 -4 spaghetti.pizza
|
|
PING spaghetti.pizza (172.67.192.217) 56(84) bytes of data.
|
|
64 bytes from 172.67.192.217: icmp_seq=1 ttl=255 time=37.3 ms
|
|
|
|
--- spaghetti.pizza ping statistics ---
|
|
1 packets transmitted, 1 received, 0% packet loss, time 0ms
|
|
# ping -c1 -6 spaghetti.pizza
|
|
PING spaghetti.pizza(2606:4700:3034::6815:147a (2606:4700:3034::6815:147a)) 56 data bytes
|
|
64 bytes from 2606:4700:3034::6815:147a: icmp_seq=1 ttl=255 time=35.6 ms
|
|
|
|
--- spaghetti.pizza ping statistics ---
|
|
1 packets transmitted, 1 received, 0% packet loss, time 0ms
|
|
rtt min/avg/max/mdev = 35.605/35.605/35.605/0.000 ms
|
|
# logout
|
|
$
|
|
|
|
.RE
|
|
.fi
|
|
|
|
.BR "Connect an existing user and network namespace"
|
|
.RS
|
|
.nf
|
|
$ unshare -rUn
|
|
# echo $$
|
|
2446678
|
|
|
|
.fi
|
|
.BR " [From another terminal]"
|
|
.nf
|
|
$ ./pasta 2446678
|
|
Outbound interface: eth0, namespace interface: eth0
|
|
ARP:
|
|
address: 28:16:ad:39:a9:ea
|
|
DHCP:
|
|
assign: 192.168.1.118
|
|
mask: 255.255.255.0
|
|
router: 192.168.1.1
|
|
NDP/DHCPv6:
|
|
assign: 2a02:6d40:3ca5:2001:b81d:fa4a:8cdd:cf17
|
|
router: fe80::62e3:27ff:fe33:2b01
|
|
|
|
.fi
|
|
.BR " [Back to the original terminal]"
|
|
.nf
|
|
# dhclient -4 --no-pid
|
|
# dhclient -6 --no-pid
|
|
# ip address show
|
|
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
|
|
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
|
|
inet 127.0.0.1/8 scope host lo
|
|
valid_lft forever preferred_lft forever
|
|
inet6 ::1/128 scope host
|
|
valid_lft forever preferred_lft forever
|
|
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 65520 qdisc pfifo_fast state UNKNOWN group default qlen 1000
|
|
link/ether fa:c1:2a:27:92:a9 brd ff:ff:ff:ff:ff:ff
|
|
inet 192.168.1.118/24 brd 192.168.1.255 scope global eth0
|
|
valid_lft forever preferred_lft forever
|
|
inet6 2a02:6d40:3ca5:2001:b81d:fa4a:8cdd:cf17/128 scope global
|
|
valid_lft forever preferred_lft forever
|
|
inet6 2a02:6d40:3ca5:2001:f8c1:2aff:fe27:92a9/64 scope global dynamic mngtmpaddr
|
|
valid_lft 3594sec preferred_lft 3594sec
|
|
inet6 fe80::f8c1:2aff:fe27:92a9/64 scope link
|
|
valid_lft forever preferred_lft forever
|
|
.fi
|
|
.RE
|
|
|
|
.SS \fBpasst
|
|
.BR "Start and connect a guest with basic port forwarding"
|
|
.RS
|
|
.nf
|
|
$ ./passt -f -t 2222:22
|
|
Outbound interface: eth0
|
|
ARP:
|
|
address: 28:16:ad:39:a9:ea
|
|
DHCP:
|
|
assign: 192.168.1.118
|
|
mask: 255.255.255.0
|
|
router: 192.168.1.1
|
|
search:
|
|
redhat.com
|
|
NDP/DHCPv6:
|
|
assign: 2a02:6d40:3ca5:2001:b81d:fa4a:8cdd:cf17
|
|
router: fe80::62e3:27ff:fe33:2b01
|
|
search:
|
|
redhat.com
|
|
UNIX domain socket bound at /tmp/passt_1.socket
|
|
|
|
You can now start qrap:
|
|
./qrap 5 qemu-system-x86_64 ... -net socket,fd=5 -net nic,model=virtio
|
|
or directly qemu, patched with:
|
|
qemu/0001-net-Allow-also-UNIX-domain-sockets-to-be-used-as-net.patch
|
|
as follows:
|
|
qemu-system-x86_64 ... -net socket,connect=/tmp/passt_1.socket -net nic,model=virtio
|
|
|
|
.fi
|
|
.BR " [From another terminal]"
|
|
.nf
|
|
$ ./qrap 5 qemu-system-x86_64 test.qcow2 -m 1024 -display none -nodefaults -nographic -net socket,fd=5 -net nic,model=virtio
|
|
Connected to /tmp/passt_1.socket
|
|
|
|
.fi
|
|
.BR " [Back to the original terminal]"
|
|
.nf
|
|
passt: DHCP: ack to request
|
|
passt: from 52:54:00:12:34:56
|
|
passt: NDP: received NS, sending NA
|
|
passt: NDP: received RS, sending RA
|
|
passt: DHCPv6: received SOLICIT, sending ADVERTISE
|
|
passt: NDP: received NS, sending NA
|
|
passt: DHCPv6: received REQUEST/RENEW/CONFIRM, sending REPLY
|
|
passt: NDP: received NS, sending NA
|
|
|
|
.fi
|
|
.BR " [From yet another terminal]"
|
|
.nf
|
|
$ ssh -p 2222 root@localhost
|
|
root@localhost's password:
|
|
.fi
|
|
.BR " [...]"
|
|
.nf
|
|
# ip address show
|
|
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
|
|
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
|
|
inet 127.0.0.1/8 scope host lo
|
|
valid_lft forever preferred_lft forever
|
|
inet6 ::1/128 scope host
|
|
valid_lft forever preferred_lft forever
|
|
2: ens2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 65520 qdisc pfifo_fast state UP group default qlen 1000
|
|
link/ether 52:54:00:12:34:56 brd ff:ff:ff:ff:ff:ff
|
|
inet 192.168.1.118/24 brd 192.168.1.255 scope global noprefixroute ens2
|
|
valid_lft forever preferred_lft forever
|
|
inet6 2a02:6d40:3ca5:2001:b81d:fa4a:8cdd:cf17/128 scope global noprefixroute
|
|
valid_lft forever preferred_lft forever
|
|
inet6 2a02:6d40:3ca5:2001:b019:9ae2:a2fe:e6b4/64 scope global dynamic noprefixroute
|
|
valid_lft 3588sec preferred_lft 3588sec
|
|
inet6 fe80::1f98:d09f:9309:9e77/64 scope link noprefixroute
|
|
valid_lft forever preferred_lft forever
|
|
.fi
|
|
.RE
|
|
|
|
.SH NOTES
|
|
|
|
.SS Handling of traffic with loopback destination and source addresses
|
|
|
|
Both \fBpasst\fR and \fBpasta\fR can bind on ports with a loopback
|
|
address (127.0.0.0/8 or ::1), depending on the configuration. Loopback
|
|
destination or source addresses need to be changed before packets are
|
|
delivered to the guest or target namespace: most operating systems
|
|
would drop packets received with loopback addresses on non-loopback
|
|
interfaces, and it would also be impossible for guest or target
|
|
namespace to route answers back.
|
|
|
|
For convenience, the source address on these packets is translated to
|
|
the address specified by the \fB\-\-map-host-loopback\fR option (with
|
|
some exceptions in pasta mode, see next section below). If not
|
|
specified this defaults, somewhat arbitrarily, to the address of
|
|
default IPv4 or IPv6 gateway (if any) -- this is known to be an
|
|
existing, valid address on the same subnet. If \fB\-\-no-map-gw\fR or
|
|
\fB\-\-map-host-loopback none\fR are specified this translation is
|
|
disabled and packets with loopback addresses are simply dropped.
|
|
|
|
Loopback destination addresses are translated to the observed external
|
|
address of the guest or target namespace. For IPv6, the observed
|
|
link-local address is used if the translated source address is
|
|
link-local, otherwise the observed global address is used. For both
|
|
IPv4 and IPv6, if no addresses have been seen yet, the configured
|
|
addresses will be used instead.
|
|
|
|
For example, if \fBpasst\fR or \fBpasta\fR receive a connection from 127.0.0.1,
|
|
with destination 127.0.0.10, and the default IPv4 gateway is 192.0.2.1, while
|
|
the last observed source address from guest or namespace is 192.0.2.2, this will
|
|
be translated to a connection from 192.0.2.1 to 192.0.2.2.
|
|
|
|
Similarly, for traffic coming from guest or namespace, packets with
|
|
destination address corresponding to the \fB\-\-map-host-loopback\fR
|
|
address will have their destination address translated to a loopback
|
|
address.
|
|
|
|
.SS Handling of local traffic in pasta
|
|
|
|
Depending on the configuration, \fBpasta\fR can bind to local ports in the init
|
|
namespace, in the target namespace, or both, and forward connections and packets
|
|
to corresponding ports in the other namespace.
|
|
|
|
To avoid unnecessary overhead, these connections and packets are not forwarded
|
|
through the tap device connecting the namespaces: \fBpasta\fR creates a socket
|
|
in the destination namespace, with matching Layer-4 protocol, and uses it to
|
|
forward local data. For TCP, data is forwarded between the originating socket
|
|
and the new socket using the \fBsplice\fR(2) system call, and for UDP, a pair
|
|
of \fBrecvmmsg\fR(2) and \fBsendmmsg\fR(2) system calls deals with packet
|
|
transfers.
|
|
|
|
Because it's not possible to bind sockets to foreign addresses, this
|
|
bypass only applies to local connections and traffic. It also means
|
|
that the address translation differs slightly from passt mode.
|
|
Connections from loopback to loopback on the host will appear to come
|
|
from the target namespace's public address within the guest, unless
|
|
\fB\-\-host-lo-to-ns-lo\fR is specified, in which case they will
|
|
appear to come from loopback in the namespace as well. The latter
|
|
behaviour used to be the default, but is usually undesirable, since it
|
|
can unintentionally expose namespace local services to the host.
|
|
|
|
.SS Binding to low numbered ports (well-known or system ports, up to 1023)
|
|
|
|
If the port forwarding configuration requires binding to ports with numbers
|
|
lower than 1024, \fBpasst\fR and \fBpasta\fR will try to bind to them, but will
|
|
fail, unless, either:
|
|
|
|
.IP \(bu 2
|
|
the \fIsys.net.ipv4.ip_unprivileged_port_start\fR sysctl is set to the number
|
|
of the lowest port \fBpasst\fR and \fBpasta\fR need. For example, as root:
|
|
|
|
.nf
|
|
sysctl -w net.ipv4.ip_unprivileged_port_start=443
|
|
.fi
|
|
|
|
\fBNote\fR: this is the recommended way of enabling \fBpasst\fR and \fBpasta\fR
|
|
to bind to ports with numbers below 1024.
|
|
|
|
.IP \(bu
|
|
or the \fICAP_NET_BIND_SERVICE\fR Linux capability is granted, see
|
|
\fBservices\fR(5) and \fBcapabilities\fR(7).
|
|
|
|
This is, in general, \fBnot the recommended way\fR, because \fBpasst\fR and
|
|
\fBpasta\fR might be used as vector to effectively use this capability from
|
|
another process.
|
|
|
|
However, if your environment is sufficiently controlled by an LSM (Linux
|
|
Security Module) such as \fIAppArmor\fR, \fISELinux\fR, \fISmack\fR or
|
|
\fITOMOYO\fR, and no other processes can interact in such a way in virtue of
|
|
this, granting this capability to \fBpasst\fR and \fBpasta\fR only can
|
|
effectively prevent other processes from utilising it.
|
|
|
|
Note that this will not work for automatic detection and forwarding of ports
|
|
with \fBpasta\fR, because \fBpasta\fR will relinquish this capability at
|
|
runtime.
|
|
|
|
To grant this capability, you can issue, as root:
|
|
|
|
.nf
|
|
for p in $(which passt passt.avx2); do
|
|
setcap 'cap_net_bind_service=+ep' "${p}"
|
|
done
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.SS ICMP/ICMPv6 Echo sockets
|
|
|
|
ICMP and ICMPv6 Echo requests coming from guest or target namespace are handled
|
|
using so-called "ping" sockets, introduced in Linux 2.6.30. To preserve the
|
|
original identifier (see RFC 792, page 14, for ICMP, and RFC 4443, section 4.1,
|
|
for ICMPv6), \fBpasst\fR and \fBpasta\fR try to bind these sockets using the
|
|
observed source identifier as "port" -- that corresponds to Echo identifiers
|
|
for "ping" sockets.
|
|
|
|
As \fBbind\fR(2) failures were seen with particularly restrictive SELinux
|
|
policies, a fall-back mechanism maps different identifiers to different sockets,
|
|
and identifiers in replies will be mapped back to the original identifier of the
|
|
request. However, if \fBbind\fR(2) fails and the fall-back mechanism is used,
|
|
echo requests will be forwarded with different, albeit unique, identifiers.
|
|
|
|
For ICMP and ICMPv6 Echo requests to work, the \fIping_group_range\fR parameter
|
|
needs to include the PID of \fBpasst\fR or \fBpasta\fR, see \fBicmp\fR(7).
|
|
|
|
.SS pasta and loopback interface
|
|
|
|
As \fBpasta\fR connects to an existing namespace, or once it creates a new
|
|
namespace, it will also ensure that the loopback interface, \fIlo\fR, is brought
|
|
up. This is needed to bind ports using the loopback address in the namespace.
|
|
|
|
.SS TCP sending window and \fITCP_INFO\fB before Linux 5.3
|
|
|
|
To synchronise the TCP sending window from host Layer-4 sockets to the TCP
|
|
parameters announced in TCP segments sent over the Layer-2 interface,
|
|
\fBpasst\fR and \fBpasta\fR routinely query the size of the sending window seen
|
|
by the kernel on the corresponding socket using the \fITCP_INFO\fR socket
|
|
option, see \fBtcp\fR(7). Before Linux 5.3, i.e. before Linux kernel commit
|
|
8f7baad7f035 ("tcp: Add snd_wnd to TCP_INFO"), the sending window
|
|
(\fIsnd_wnd\fR field) is not available.
|
|
|
|
If the sending window cannot be queried, it will always be announced as the
|
|
current sending buffer size to guest or target namespace. This might affect
|
|
throughput of TCP connections.
|
|
|
|
.SS Local mode for disconnected setups
|
|
|
|
If \fBpasst\fR and \fBpasta\fR fail to find a host interface with a configured
|
|
address, other than loopback addresses, they will, obviously, not attempt to
|
|
source addresses or routes from the host.
|
|
|
|
In this case, unless configured otherwise, they will assign the IPv4 link-local
|
|
address 169.254.2.1 to the guest or target namespace, and no IPv6 address. The
|
|
notion of the guest or target namespace IPv6 address is derived from the first
|
|
link-local address observed.
|
|
|
|
Default gateways will be assigned as the link-local address 169.254.2.2 for
|
|
IPv4, and as the link-local address fe80::1 for IPv6.
|
|
|
|
.SH LIMITATIONS
|
|
|
|
Currently, IGMP/MLD proxying (RFC 4605) and support for SCTP (RFC 4960) are not
|
|
implemented.
|
|
|
|
TCP Selective Acknowledgment (RFC 2018), as well as Protection Against Wrapped
|
|
Sequences (PAWS) and Round-Trip Time Measurement (RTTM), both described by RFC
|
|
7232, are currently not implemented.
|
|
|
|
.SH AUTHORS
|
|
|
|
Stefano Brivio <sbrivio@redhat.com>, David Gibson <david@gibson.dropbear.id.au>.
|
|
|
|
.SH REPORTING BUGS
|
|
|
|
Please report issues on the bug tracker at https://passt.top/passt/bugs, or
|
|
send a message to the passt-user@passt.top mailing list, see
|
|
https://passt.top/passt/lists.
|
|
|
|
.SH COPYRIGHT
|
|
|
|
Copyright (c) 2020-2022 Red Hat GmbH.
|
|
|
|
\fBpasst\fR and \fBpasta\fR are free software: you can redistribute them and/or
|
|
modify them under the terms of the GNU General Public License as
|
|
published by the Free Software Foundation, either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
.SH SEE ALSO
|
|
|
|
\fBnamespaces\fR(7), \fBqemu\fR(1), \fBqrap\fR(1), \fBslirp4netns\fR(1).
|
|
|
|
High-level documentation is available at https://passt.top/passt/about/.
|