passt/inany.c, branch bug209

conf: Use new parsing tools to handle -a option

2026-07-04T11:14:25+00:00

The -a command line option can take either an address prefix, or a bare
address.  Current parsing of this is pretty awkward, using the special
purpose helper inany_prefix_pton().  With the new incremental parsing
helpers this can be done more naturally.  Rework it to use them.

This does requiring extending parse_inany() to parse_inany_() which also
reports the format of the address as parse, as opposed to the family of
the resulting address.  This is so that ::ffff:192.0.1.1/112 will be
correctly interpreted the same as 192.0.1.1/16, rather than the
nonsensical 192.0.0.1/112.

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio

parse: Add helpers for parsing IP addresses

2026-07-04T11:14:09+00:00

parse_ipv[46]() are wrappers around inet_pton() that are more
convenient for use when the IP is part of a longer string, rather than
the entire string.  parse_inany() replaces inany_pton() which again
will become more convenient for strings including IPs that aren't just
an IP.

For now we only have some simple and sometimes awkward use cases,
we'll replace these with more natural uses in future.

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio

inany: Prepare inany.[ch] for sharing with pesto tool

2026-05-07T06:06:30+00:00

inany contains a number of helpful functions for dealing with addresses
which might be IPv4 or IPv6.  We're going to want to use that in pesto.
For the most part inany doesn't depend on other passt/pasta internals,
however it does depend on siphash.h, which pesto doesn't need.

Move the single dependent function, inany_siphash_feed() to siphash.h,
renaming to match.  Use that include inany.[ch] into pesto as well as
passt/pasta.  While we're there reformat pesto.c's header comment to match
the convention used in most other files.

Signed-off-by: David Gibson 
Reviewed-by: Laurent Vivier 
Signed-off-by: Stefano Brivio

conf: Support CIDR notation for -a/--address option

2026-02-24T11:05:53+00:00

We extend the -a/--address option to accept addresses in CIDR notation
(e.g., 192.168.1.1/24 or 2001:db8::1/64) as an alternative to using
separate -a and -n options.

We add a new inany_prefix_pton() helper function that:
- Parses address strings with a compulsory /prefix_len suffix
- Validates prefix length based on address family (0-32 for IPv4,
  0-128 for IPv6), including handling of IPv4-to-IPv6 mapping case.

For IPv4, the prefix length is stored in ip4.prefix_len when provided.
For IPv6, the given prefix length is still overridden by the default
value 64

Mixing -n and CIDR notation results in an error to catch likely user
mistakes.

Also fix a bug in conf_ip4_prefix() that was incorrectly using the
global 'optarg' instead of its 'arg' parameter.

Signed-off-by: Jon Maloy 
[sbrivio: Fix merge conflict with commit 0c611bcd3120]
Signed-off-by: Stefano Brivio

conf, fwd: Check forwarding table for conflicting rules

2026-01-18T11:47:53+00:00

It's possible for a user to supply conflicting forwarding parameters, e.g.
    $ pasta -t 80:8080 -t 127.0.0.1/80:8888

We give a warning in this case, but it's based on the legacy
forwarding bitmaps.  This is too strict, because it will also warn on
cases that shouldn't conflict because they use different addresses,
e.g.
    $ pasta -t 192.0.2.1/80:8080 127.0.0.1/80:8888

Theoretically, it's also too loose because it won't take into account
auto-scan forwarding rules.  We can't hit that in practice now,
because we only ever have one auto-scan rule and nothing else, but we
want to remove that restriction in future.

Replace the bitmap based check with a check based on actually scanning
the forwarding rules for conflicts.

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio

inany: Extend inany_ntop() to treat NULL as a fully unspecified address

2026-01-18T11:47:29+00:00

In a number of places we're using a convention that a NULL inany represents
a dual-stack unspecified address, that is one which includes both 0.0.0.0
and ::.  Extend inany_ntop() to handle that convention, representing it
as "*".

Signed-off-by: David Gibson 
Reviewed-by: Laurent Vivier 
Signed-off-by: Stefano Brivio

arp/ndp: respond with true MAC address of LAN local remote hosts

2025-10-30T11:01:01+00:00

When we receive an ARP request or NDP neigbour solicitation over
the tap interface for a host on the local network segment attached
to the template interface, we respond with that host's real MAC
address, if available.

Signed-off-by: Jon Maloy 
Reviewed-by: David Gibson 
Signed-off-by: Stefano Brivio

style: Fix 'Return' comment style

2025-07-18T17:19:24+00:00

We always use imperative (no 'Returns:'), no tab after the ':' and
only one space, the first character is always lowercase.

This is fixed with:

 sed -i "s/Returns:/Return:/;s/Return:    /Return: /;s/Return:  */Return: /;s/Return: \([A-Z]\)/Return: \L\1/" *.[ch]

And manually updated to fix alignment of multiline comment and words
that must keep uppercase (like IPv4, TCP, UDP, Layer-4).

Signed-off-by: Laurent Vivier 
Signed-off-by: Stefano Brivio

inany: Add inany_pton() helper

2024-09-25T17:03:17+00:00

We already have an inany_ntop() function to format inany addresses into
text.  Add inany_pton() to parse them from text, and use it in
conf_ports().

Signed-off-by: David Gibson

inany: Better helpers for using inany and specific family addrs together

2024-05-22T21:20:55+00:00

This adds some extra inany helpers for comparing an inany address to
addresses of a specific family (including special addresses), and building
an inany from an IPv4 address (either statically or at runtime).

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio