Commit graph

1260 commits

Author SHA1 Message Date
David Gibson
672a8cd80e pasta: More general way of starting spawned shell as a login shell
When invoked so as to spawn a shell, pasta checks explicitly for the
shell being bash and if so, adds a "-l" option to make it a login shell.
This is not ideal, since this is a bash specific option and requires pasta
to know about specific shell variants.

There's a general convention for starting a login shell, which is to
prepend a "-" to argv[0].  Use this approach instead, so we don't need bash
specific logic.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-15 02:10:36 +02:00
David Gibson
f99e9a3338 test: Move slower tests to end of test run
The distro and performance tests are by far the slowest part of the passt
testsuite.  Move them to the end of the testsuite run, so that it's easier
to do a quick test during development by letting the other tests run then
interrupting the test runner.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-15 02:10:36 +02:00
Stefano Brivio
7f2a7396e2 log.h: Avoid unnecessary GNU extension for token pasting
clang says:

  ./log.h:23:18: warning: token pasting of ',' and __VA_ARGS__ is a GNU extension [-Wgnu-zero-variadic-macro-arguments]

We need token pasting here just because of the 'format' in trace():
drop it.

Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-15 02:10:36 +02:00
Stefano Brivio
55cdcc159b util.h: Add missing gcc pragma push before pragma pop
While building with clang:

  ./util.h:176:24: warning: pragma diagnostic pop could not pop, no matching push [-Wunknown-pragmas]

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
abbe01af59 icmp: Set sin6_scope_id for outbound ICMPv6 echo requests
If we ping a link-local address, we need to pass this to sendto(), as
it will obviously fail with -EINVAL otherwise.

If we ping other addresses, it's probably a good idea anyway to
specify the configured outbound interface here.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
57e2c066e9 conf: Drop excess colons in usage for DHCP and DNS options
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
6acf89638b netlink: Disable duplicate address detection for configured IPv6 address
With default options, when we pass --config-net, the IPv6 address is
actually going to be recycled from the init namespace, so it is in
fact duplicated, but duplicate address detection has no way to find
out.

With a different configured address, that's not the case, but anyway
duplicate address detection will be unable to see this.

In both cases, we're wasting time for nothing.

Pass the IFA_F_NODAD flag as we configure globally scoped IPv6
addresses via netlink.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
6f3e38cac5 Don't create 'tap' socket for ports that are bound to loopback only
If the user specifies an explicit loopback address for a port
binding, we're going to use that address for the 'tap' socket, and
the same exact address for the 'spliced' socket (because those are,
by definition, only bound to loopback addresses).

This means that the second binding will fail, and, unexpectedly, the
port is forwarded, but via tap device, which means the source address
in the namespace won't be a loopback address.

Make it explicit under which conditions we're creating which kind of
socket, by refactoring tcp_sock_init() into two separate functions
for IPv4 and IPv6 and gathering those conditions at the beginning.

Also, don't create spliced sockets if the user specifies explicitly
a non-loopback address, those are harmless but not desired either.

Fixes: 3c6ae62510 ("conf, tcp, udp: Allow address specification for forwarded ports")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-15 02:10:36 +02:00
Stefano Brivio
d0dd0242a6 tcp, tcp_splice: Fix port remapping for inbound, spliced connections
In pasta mode, when we receive a new inbound connection, we need to
select a socket that was created in the namespace to proceed and
connect() it to its final destination.

The existing condition might pick a wrong socket, though, if the
destination port is remapped, because we'll check the bitmap of
inbound ports using the remapped port (stored in the epoll reference)
as index, and not the original port.

Instead of using the port bitmap for this purpose, store this
information in the epoll reference itself, by adding a new 'outbound'
bit, that's set if the listening socket was created the namespace,
and unset otherwise.

Then, use this bit to pick a socket on the right side.

Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Fixes: 33482d5bf2 ("passt: Add PASTA mode, major rework")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
eab9d8d5d6 tcp, tcp_splice: Adjust comments to current meaning of inbound and outbound
For tcp_sock_init_ns(), "inbound" connections used to be the ones
being established toward any listening socket we create, as opposed
to sockets we connect().

Similarly, tcp_splice_new() used to handle "inbound" connections in
the sense that they originated from listening sockets, and they would
in turn cause a connect() on an "outbound" socket.

Since commit 1128fa03fe ("Improve types and names for port
forwarding configuration"), though, inbound connections are more
broadly defined as the ones directed to guest or namepsace, and
outbound the ones originating from there.

Update comments for those two functions.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
346da48fe6 udp: Fix port and address checks for DNS forwarder
First off, as we swap endianness for source ports in
udp_fill_data_v{4,6}(), we want host endianness, not network
endianness. It doesn't actually matter if we use htons() or ntohs()
here, but the current version is confusing.

In the IPv4 path, when we remap DNS answers, we already swapped the
endianness as needed for the source port: don't swap it again,
otherwise we'll not map DNS answers for IPv4.

In the IPv6 path, when we remap DNS answers, we want to check that
they came from our upstream DNS server, not the one configured via
--dns-forward (which doesn't even need to exist for this
functionality to work).

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
2970dc257c tap: Don't check sequence counts when adding packets to pool
This is a minor optimisation possibility I spotted while trying to
debug a hang in tap4_handler(): if we run out of space for packet
sequences, it's fine to add packets to an existing per-sequence pool.

We should check the count of packet sequences only once we realise
that we actually need a new packet sequence.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-15 02:10:36 +02:00
Stefano Brivio
cc65f31250 packet: Fix off-by-one in packet_get_do() sanity checks
An n-sized pool, or a pool with n entries, doesn't include index n,
only up to n - 1.

I'm not entirely sure this sanity check actually covers any
practical case, but I spotted this while debugging a hang in
tap4_handler() (possibly due to malformed sequence entries from
qemu).

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
10236de486 conf: Report usage for --no-netns-quit
Fixes: 745a9ba428 ("pasta: By default, quit if filesystem-bound net namespace goes away")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
c1eff9a3c6 conf, tcp, udp: Allow specification of interface to bind to
Since kernel version 5.7, commit c427bfec18f2 ("net: core: enable
SO_BINDTODEVICE for non-root users"), we can bind sockets to
interfaces, if they haven't been bound yet (as in bind()).

Introduce an optional interface specification for forwarded ports,
prefixed by %, that can be passed together with an address.

Reported use case: running local services that use ports we want
to have externally forwarded:
  https://github.com/containers/podman/issues/14425

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
a62ed181db conf, tap: Add option to quit once the client closes the connection
This is practical to avoid explicit lifecycle management in users,
e.g. libvirtd, and is trivial to implement.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
9de65dd3f4 util: Check return value of lseek() while reading bound ports from procfs
Coverity now noticed we're checking most lseek() return values, but
not this. Not really relevant, but it doesn't hurt to check we can
actually seek before reading lines.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-15 02:10:36 +02:00
Stefano Brivio
e23024ccff conf, log, Makefile: Add versioning information
Add a --version option displaying that, and also include this
information in the log files.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-15 02:10:28 +02:00
Stefano Brivio
2074b332f9 log: Add missing function comment for trace_init()
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-14 17:38:58 +02:00
Stefano Brivio
01efc71ddd log, conf: Add support for logging to file
In some environments, such as KubeVirt pods, we might not have a
system logger available. We could choose to run in foreground, but
this takes away the convenient synchronisation mechanism derived from
forking to background when interfaces are ready.

Add optional logging to file with -l/--log-file and --log-size.

Unfortunately, this means we need to duplicate features that are more
appropriately implemented by a system logger, such as rotation. Keep
that reasonably simple, by using fallocate() with range collapsing
where supported (Linux kernel >= 3.15, extent-based ext4 and XFS) and
falling back to an unsophisticated block-by-block moving of entries
toward the beginning of the file once we reach the (mandatory) size
limit.

While at it, clarify the role of LOG_EMERG in passt.c.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-14 17:38:28 +02:00
Stefano Brivio
f4e1e88e1d passt.h: Include netinet/if_ether.h before struct ctx declaration
This saves some hassle when including passt.h, as we need ETH_ALEN
there.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-14 17:38:28 +02:00
Stefano Brivio
51fa9bfd7b conf: Drop duplicate, diverging optstring assignments
This originated as a result of copy and paste to introduce a second
stage for processing options related to port forwarding, has already
bitten David in the past, and just gave me hours of fun.

As a matter of fact, the second set of optstring assignments was
already incorrect, but it didn't matter because the first one was
more restrictive, not allowing optional arguments for -P, -D, -S.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-14 17:38:26 +02:00
Stefano Brivio
da152331cf Move logging functions to a new file, log.c
Logging to file is going to add some further complexity that we don't
want to squeeze into util.c.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-14 17:38:25 +02:00
Stefano Brivio
c4101334e1 test: Add rudimentary support to run selected tests only
To keep this simple, only support tests that have corresponding setup
and teardown functions implied by their path. For example:

  ./run passt/ndp

will trigger the 'passt' setup and teardown functions.

This is not really elegant, but it looks robust, and while David is
considering proper alternatives, it should be quite useful.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-14 17:38:24 +02:00
Stefano Brivio
06aa26fcf3 Makefile: Hack for optimised-away store in ndp() before checksum calculation
With gcc 11 and 12, passing -flto, or -flto=auto, and -O2,
intra-procedural optimisation gets rid of a fundamental bit in ndp():
the store of hop_limit in the IPv6 header, before the checksum is
calculated, which on x86_64 looks like this:

	ip6hr->hop_limit = IPPROTO_ICMPV6;
    b8c0:	c6 44 24 35 3a       	movb   $0x3a,0x35(%rsp)

Here, hop_limit is temporarily set to the protocol number, to
conveniently get the IPv6 pseudo-header for ICMPv6 checksum
calculation in memory.

With LTO, the assignment just disappears from the binary.

This is rather visible as NDP messages get a wrong checksum, namely
the expected checksum plus 58, and they're ignored by the guest or
in the namespace, meaning we can't get any IPv6 routes, as reported
by Wenli Quan.

The issue affects a significant number of distribution builds,
including the ones for CentOS Stream 9, EPEL 9, Fedora >= 35,
Mageia Cauldron, and openSUSE Tumbleweed.

As a quick workaround, declare csum_unaligned() as "noipa" for gcc
11 and 12, with -flto and -O2. This disables inlining and cloning,
which causes the assignment to be compiled again.

Leave a TODO item: we should figure out if a gcc issue has already
been reported, and report one otherwise. There's no apparent
justification as to why the store could go away.

Reported-by: Wenli Quan <wquan@redhat.com>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2129713
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:23:11 +02:00
Stefano Brivio
5290b6f13e udp: Replace pragma to ignore bogus stringop-overread warning with workaround
Commit c318ffcb4c ("udp: Ignore bogus -Wstringop-overread for
write() from gcc 12.1") uses a gcc pragma to ignore a bogus warning,
which started appearing on gcc 12.1 (aarch64 and x86_64) due to:
  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103483

...but gcc 12.2 has the same issue. Not just that: if LTO is enabled,
the pragma itself is ignored (this wasn't the case with gcc 12.1),
because of:
  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80922

Drop the pragma, and assign a frame (in the networking sense) pointer
from the offset of the Ethernet header in the buffer, then pass it to
write() and pcap(), so that gcc doesn't obsess anymore with the fact
that an Ethernet header is 14 bytes and we're sending more than that.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:23:10 +02:00
Stefano Brivio
505a33e9f9 Makefile: Extend noinline workarounds for LTO and -O2 to gcc 12
Commit 1a563a0cbd ("passt: Address gcc 11 warnings") works around an
issue where the remote address passed to hash functions is seen as
uninitialised by gcc, with -flto and -O2.

It turns out we get the same exact behaviour on gcc 12.1 and 12.2, so
extend the applicability of the same workaround to gcc 12.

Don't go further than that, though: should the issue reported at:
  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78993
happen to be fixed in a later version of gcc, we won't need the
noinline attributes anymore. Otherwise, we'll notice.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:23:07 +02:00
David Gibson
65b649017c cppcheck: Remove unused unmatchedSuppression suppressions
It's unclear what original suppressions these unmatchedSuppression
suppressions were supposed to go with.  They don't trigger any warnings on
the current code that I can tell, so remove them.  If we find a problem
with some cppcheck versions in future, replace them with inline
suppressions so it's clearer exactly where the issue is originating.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:23:05 +02:00
David Gibson
f5d053034c Mark unused functions for cppcheck
We have a couple of functions that are unused (for now) by design.
Although at least one has a flag so that gcc doesn't warn, cppcheck has its
own warnings about this.  Add specific inline suppressions for these rather
than a blanket suppression in the Makefile.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:23:03 +02:00
David Gibson
cd05be75fb cppcheck: Remove unused va_list_usedBeforeStarted suppression
I can't get this warning to trigger, even without the suppression, so
remove it.  If it shows up again on some cppcheck version, we can replace
it with inline suppressions so it's clear where the issue lay.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:23:01 +02:00
David Gibson
5f77ac24c5 cppcheck: Remove unused objectIndex suppressions
I can't get these warnings to trigger on the cppcheck versions I have, so
remove them.  If we find in future we need to replace these, they should be
replaced with inline suppressions so its clear what's the section of code
at issue.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:57 +02:00
David Gibson
20a3427812 cppcheck: Remove unused knownConditionTrueFalse suppression
I can't get this warning to trigger, so I think this suppression must be
out of date.  Whether that's because we've changed our code to no longer
have the problem, or because cppcheck itself has been updated to remove a
false positive I don't know.

If we find that we do need a suppression like this for some cppcheck
version, we should replace it with an inline suppression so it's clear
what exactly is triggering the warning.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:54 +02:00
David Gibson
5beb3472ed cppcheck: Avoid errors due to zeroes in bitwise ORs
Recent versions of cppcheck give warnings if using a bitwise OR (|) where
some of the arguments are zero.  We're triggering these warnings in our
generated seccomp.h header, because BPF_LD and BPF_W are zero-valued.
However putting these defines in makes the generate code clearer, even
though they could be left out without changing the values.  So, add
cppcheck suppressions to the generated code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:37 +02:00
David Gibson
0616620805 Regenerate seccomp.h if seccomp.sh changes
seccomp.sh generates seccomp.h, so if we change it, we should re-build
seccomp.h as well.  Add this to the make dependencies so it happens.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:34 +02:00
David Gibson
1ae95f33cc cppcheck: Suppress NULL pointer warning in tcp_sock_consume()
Recent versions of cppcheck give a warning due to the NULL buffer passed
to recv() in tcp_sock_consume().  Since this apparently works, I assume
it's actually valid, but cppcheck doesn't know that recv() can take a NULL
buffer.  So, use a suppression to get rid of the error.

Also add an unmatchedSuppression suppression since only some cppcheck
versions complain about this.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:32 +02:00
David Gibson
8f6be016ae cppcheck: Suppress same-value-in-ternary branches warning
TIMER_INTERVAL is the minimum of two separately defined intervals which
happen to have the same value at present.  This results in an expression
which has the same value in both branches of a ternary operator, which
cppcheck warngs about.  This is logically sound in this case, so suppress
the error (we appear to already have a similar suppression for clang-tidy).

Also add an unmatchedSuppression suppression, since only some cppcheck
versions complain about this instance.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:30 +02:00
David Gibson
740ea28f29 qrap: Handle case of PATH environment variable being unset
clang-tidy warns that in passing getenv("PATH") to strncpy() we could be
passing a NULL pointer.  While it's unusual for PATH to be unset, it's not
impossible and this would indeed cause getenv() to return NULL.

Handle this case by never recognizing argv[2] as a qemu binary name if
PATH is not set.  This is... no flakier than the detection of whether
it's a binary name already is.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:28 +02:00
David Gibson
b35a6cfa0c cppcheck: Remove localtime suppression for pcap.c
Since bf95322f "conf: Make the argument to --pcap option mandatory" we
no longer call localtime() in pcap.c, so we no longer need the matching
cppcheck suppression.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:25 +02:00
David Gibson
6ce68113e3 cppcheck: Broaden suppression for unused struct members
In a number of places in passt we use structures to represent over the wire
or in-file data with a fixed layout.  After initialization we don't access
the fields individually and just write the structure as a whole to its
destination.

Unfortunately cppcheck doesn't cope with this pattern and thinks all the
structure members are unused.  We already have suppressions for this in
pcap.c and dhcp.c   However, it also appears in dhcp.c and netlink.c at
least.  Since this is likely to be common, it seems wiser to just suppress
the error globally.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:23 +02:00
David Gibson
656acdfc26 Avoid ugly 'end' members in netlink structures
We use a number of complex structures to format messages to send to
netlink.  In some cases we add imaginary 'end' members not because they
actually mean something on the wire, but so that we can use offsetof() on
the member to determine the relevant size.

Adding extra things to the structures for this is kinda nasty.  We can use
a different construct with offsetof and sizeof to avoid them.  As a bonus
this removes some cppcheck warnings about unused struct members.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:21 +02:00
David Gibson
40901c5437 cppcheck: Use inline suppression for strtok() in conf.c
strtok() is non-reentrant and old-fashioned, so cppcheck would complains
about its use in conf.c if it weren't suppressed.  We're single threaded
and strtok() is convenient though, so it's not really worth reworking at
this time.  Convert this to an inline suppression so it's adjacent to the
code its annotating.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:19 +02:00
David Gibson
6aca100469 cppcheck: Use inline suppressions for qrap.c
qrap.c uses several old-fashioned functions that cppcheck complains about.
Since it's headed for obselesence anyway, just suppress these rather than
attempting to modernize the code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:17 +02:00
David Gibson
fb15259205 cppcheck: Use inline suppression for ffsl()
We define our own ffsl() as a weak symbol, in case our C library doesn't
include it.  On glibc systems which *do* include it, this causes a cppcheck
warning because unsurprisingly our version doesn't pick the same argument
names.  Convert the suppression for this into an inline suppression.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:15 +02:00
David Gibson
e2b7d370d0 cppcheck: Work around false positive NULL pointer dereference error
Some versions of cppcheck could errneously report a NULL pointer deference
inside a sizeof().  This is now fixed in cppcheck upstream[0].  For systems
using an affected version, add a suppression to work around the bug.  Also
add an unmatchedSuppression suppression so the suppression itself doesn't
cause a warning if you *do* have a fixed cppcheck.

[0] https://github.com/danmar/cppcheck/pull/4471

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:13 +02:00
David Gibson
df74984c52 Stricter checking for nsholder.c
Add the -Wextra -pedantic and -std=c99 flags when compiling the nsholder
test helper to get extra compiler checks, like we already use for the
main source code.

While we're there, fix some %d (signed) printf descriptors being used
for unsigned values (uid_t and gid_t).  Pointed out by cppcheck.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:10 +02:00
David Gibson
a668d87e7e Don't shadow global function names
cppcheck points out that qrap's main shadows the global err() function with
a local.  Rename it to rc to avoid the clash.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:07 +02:00
David Gibson
ab96da98cd Don't shadow 'i' in conf_ports()
The counter 'i' is used in a number of places in conf_ports(), but in one
of those we unnecessarily shadow it in an inner scope.  We could re-use the
same 'i' every time, but each use is logically separate, so instead remove
the outer declaration and declare it locally in each of the clauses where
we need it.

While we're there change it from a signed to unsigned int, since it's used
to iterate over port numbers which are generally treated as unsigned.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:05 +02:00
David Gibson
eb5e123038 cppcheck: Reduce scope of some variables
Minor style improvement suggested by cppcheck.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:22:01 +02:00
David Gibson
68ef4931cb Clean up parsing in conf_runas()
conf_runas() handles several of the different possible cases for the
--runas argument in a slightly odd order.  Although it can parse both
numeric UIDs/GIDs and user/group names, it can't parse a numeric UID
combined with a group name or vice versa.  That's not obviously useful, but
it's slightly surprising gap to have.

Rework the parsing to be more systematic: first split the option into
user and (optional) group parts, then separately parse each part as either
numeric or a name.  As a bonus this removes some clang-tidy warnings.

While we're there also add cppcheck suppressions for getpwnam() and
getgrnam().  It complains about those because they're not reentrant.
passt is single threaded though, and is always likely to be during
this initialization code, even if we multithread later.

There were some existing suppressions for these in the cppcheck
invocation but they're no longer up to date.  Replace them with inline
suppressions which, being next to the code, are more likely to stay
correct.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:21:58 +02:00
David Gibson
7d4e50827c Pack DHCPv6 "on wire" structures
dhcpv6.c contains a number of structures which represent actual DHCPv6
packets as they appear on the wire, which will break if the structures
don't have exactly the in-memory layout we expect.

Therefore, we should mark these structures as ((packed)).  The contents of
them means this is unlikely to change the layout in practice - and since
it was working, presumably didn't on any arch we were testing on.  However
it's not impossible for the compiler on some arch to insert unexpected
padding in one of these structures, so we should be explicit.

clang-tidy warned about this since we were using memcmp() to compare some
of these structures, which it thought might not have a unique
representation.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-09-29 12:21:55 +02:00