Depending on the C library, but not necessarily in all the
functions we use, statx() might be used instead of stat(),
getdents() instead of getdents64(), readlinkat() instead of
readlink(), openat() instead of open().
On aarch64, it's clone() and not fork(), and dup3() instead of
dup2() -- just allow the existing alternative instead of dealing
with per-arch selections.
Since glibc commit 9a7565403758 ("posix: Consolidate fork
implementation"), we need to allow set_robust_list() for
fork()/clone(), even in a single-threaded context.
On some architectures, epoll_pwait() is provided instead of
epoll_wait(), but never both. Same with newfstat() and
fstat(), sigreturn() and rt_sigreturn(), getdents64() and
getdents(), readlink() and readlinkat(), unlink() and
unlinkat(), whereas pipe() might not be available, but
pipe2() always is, exclusively or not.
Seen on Fedora 34: newfstatat() is used on top of fstat().
syslog() is an actual system call on some glibc/arch combinations,
instead of a connect()/send() implementation.
On ppc64 and ppc64le, _llseek(), recv(), send() and getuid()
are used. For ppc64 only: ugetrlimit() for the getrlimit()
implementation, plus sigreturn() and fcntl64().
On s390x, additionally, we need to allow socketcall() (on top
of socket()), and sigreturn() also for passt (not just for
pasta).
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This is the only remaining Linux-specific include -- drop it to avoid
clang-tidy warnings and to make code more portable.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
...mostly false positives, but a number of very relevant ones too,
in tcp_get_sndbuf(), tcp_conn_from_tap(), and siphash PREAMBLE().
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Unions and structs, you all have names now.
Take the chance to enable bugprone-reserved-identifier,
cert-dcl37-c, and cert-dcl51-cpp checkers in clang-tidy.
Provide a ffsl() weak declaration using gcc built-in.
Start reordering includes, but that's not enough for the
llvm-include-order checker yet.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Given that get_dns() touches the buffer read by line_read(), we
can't optimise that by passing the existing buffer.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
...if we check whether an option might be a namespace specification,
and it turns out not to be (e.g. with --pcap), we might set
netns_only, but we don't reset it back to 0 if it wasn't set.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Replace libc functions that might dynamically allocate memory with own
implementations or wrappers.
Drop brk(2) from list of allowed syscalls in seccomp profile.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
List of allowed syscalls comes from comments in the form:
#syscalls <list>
for syscalls needed both in passt and pasta mode, and:
#syscalls:pasta <list>
#syscalls:passt <list>
for syscalls specifically needed in pasta or passt mode only.
seccomp.sh builds a list of BPF statements from those comments,
prefixed by a binary search tree to keep lookup fast.
While at it, clean up a bit the Makefile using wildcards.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Move netlink routines to their own file, and use netlink to configure
or fetch all the information we need, except for the TUNSETIFF ioctl.
Move pasta-specific functions to their own file as well, add
parameters and calls to configure the tap interface in the namespace.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
getifaddrs() needs to allocate heap memory, and gets a ton of results
we don't need. Use explicit netlink messages with "strict checking"
instead.
While at it, separate L2/L3 address handling, so that we don't fetch
MAC addresses for IPv6, and also use netlink instead of ioctl() to
get the MAC address.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Based on a patch from Giuseppe Scrivano, this adds the ability to:
- specify paths and names of target namespaces to join, instead of
a PID, also for user namespaces, with --userns
- request to join or create a network namespace only, without
entering or creating a user namespace, with --netns-only
- specify the base directory for netns mountpoints, with --nsrun-dir
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
[sbrivio: reworked logic to actually join the given namespaces when
they're not created, implemented --netns-only and --nsrun-dir,
updated pasta demo script and man page]
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Detecting bound ports at start-up time isn't terribly useful: do this
periodically instead, if configured.
This is only implemented for TCP at the moment, UDP is somewhat more
complicated: leave a TODO there.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Before introducing options, the default behaviour in passt mode was
to forward all ports, to run in foreground and to log to stderr.
Make it a bit more convenient to restore that at build time.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
