We almost never use the named enum type, in almost all cases we use
"int" instead, since we overload it with negative errnos. To simplify
things, let's use "int" really everywhere.
Moreover, let's rename the fields for this enum to "type_or_errno", to
make the overloading clear. And let's ad some assertions that things are
in the right range.
Luca Boccassi [Tue, 16 Feb 2021 23:47:34 +0000 (23:47 +0000)]
test: avoid leaking open loop devices
When a subshell is used ('make' or 'make all') the LOOPDEV environment
variable, which is used to store the opened loop device, is lost.
So the cleanup on trap/exit doesn't do anything, and the loop
device used to mount the test image is left around.
This is an updated version of #8608 with more restrictive logic. To
quite the original bug:
Some captive portals, lie and do not respond with the captive portal
IP address, if the query is with EDNS0 enabled and D0 bit set to
zero. Thus retry "secure" domain name look ups with less secure
methods, upon NXDOMAIN.
Vito Caputo [Tue, 27 Oct 2020 06:24:34 +0000 (23:24 -0700)]
logs-show: move show_journal_by_unit _BOOT_ID match
In scrutinizing the journal overhead of `systemctl status $service`
it became apparent that the matching engine was performing the unit
matches on every journal in my system, even ones containing nothing
relevant to the current boot.
This seemed strange and likely suboptimal to me, since there's likely
far more unit data to rifle through than boot IDs in any given
journal. The _BOOT_ID match seemed like it should be serving as an
early exit match on irrelevant journals, but that wasn't what seemed
to be happening.
As a quick experiment to see if I could get the _BOOT_ID match to be
something along the lines of a higher priority when matching, and try
early exit on these unrelated journals, I moved add_match_this_boot()
to after the unit match adds, inserting a conjunction between them.
The end result seems to be a very substantial performance gain in my
simple uncached tests, and I still get the expected journal output
from the `systemctl status $service` command:
root@localhost:/# echo 2 > /proc/sys/vm/drop_caches
root@localhost:/# time systemctl --no-pager status dbus
● dbus.service - D-Bus System Message Bus
Loaded: loaded (/lib/systemd/system/dbus.service; static; vendor preset: enabled)
Active: active (running) since Sun 2020-10-25 17:03:05 PDT; 1 day 6h ago
Docs: man:dbus-daemon(1)
Main PID: 572 (dbus-daemon)
Memory: 2.8M
CPU: 110ms
CGroup: /system.slice/dbus.service
└─572 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation
Oct 25 17:03:05 localhost systemd[1]: Started D-Bus System Message Bus.
Oct 25 17:06:26 localhost dbus[572]: [system] Activating via systemd: service name='org.freedesktop.machine1' unit='dbus-org.freedesktop.machine1.service'
Oct 25 17:06:26 localhost dbus[572]: [system] Successfully activated service 'org.freedesktop.machine1'
real 0m0.695s
user 0m0.005s
sys 0m0.043s
root@localhost:/# echo 2 > /proc/sys/vm/drop_caches
root@localhost:/# time systemctl --no-pager status dbus
● dbus.service - D-Bus System Message Bus
Loaded: loaded (/lib/systemd/system/dbus.service; static; vendor preset: enabled)
Active: active (running) since Sun 2020-10-25 17:03:05 PDT; 1 day 6h ago
Docs: man:dbus-daemon(1)
Main PID: 572 (dbus-daemon)
Memory: 2.8M
CPU: 110ms
CGroup: /system.slice/dbus.service
└─572 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation
Oct 25 17:03:05 localhost systemd[1]: Started D-Bus System Message Bus.
Oct 25 17:06:26 localhost dbus[572]: [system] Activating via systemd: service name='org.freedesktop.machine1' unit='dbus-org.freedesktop.machine1.service'
Oct 25 17:06:26 localhost dbus[572]: [system] Successfully activated service 'org.freedesktop.machine1'
real 0m0.696s
user 0m0.003s
sys 0m0.046s
root@localhost:/# echo 2 > /proc/sys/vm/drop_caches
root@localhost:/# time systemctl --no-pager status dbus
● dbus.service - D-Bus System Message Bus
Loaded: loaded (/lib/systemd/system/dbus.service; static; vendor preset: enabled)
Active: active (running) since Sun 2020-10-25 17:03:05 PDT; 1 day 6h ago
Docs: man:dbus-daemon(1)
Main PID: 572 (dbus-daemon)
Memory: 2.8M
CPU: 110ms
CGroup: /system.slice/dbus.service
└─572 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation
Oct 25 17:03:05 localhost systemd[1]: Started D-Bus System Message Bus.
Oct 25 17:06:26 localhost dbus[572]: [system] Activating via systemd: service name='org.freedesktop.machine1' unit='dbus-org.freedesktop.machine1.service'
Oct 25 17:06:26 localhost dbus[572]: [system] Successfully activated service 'org.freedesktop.machine1'
root@localhost:/home/vc/gh/systemd/build# echo 2 > /proc/sys/vm/drop_caches
root@localhost:/home/vc/gh/systemd/build# time ./systemctl --no-pager status dbus
● dbus.service - D-Bus System Message Bus
Loaded: loaded (/lib/systemd/system/dbus.service; static)
Active: active (running) since Sun 2020-10-25 17:03:05 PDT; 1 day 6h ago
TriggeredBy: ● dbus.socket
Docs: man:dbus-daemon(1)
Main PID: 572 (dbus-daemon)
Memory: 2.8M
CPU: 110ms
CGroup: /system.slice/dbus.service
└─572 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation
Oct 25 17:03:05 localhost systemd[1]: Started D-Bus System Message Bus.
Oct 25 17:06:26 localhost dbus[572]: [system] Activating via systemd: service name='org.freedesktop.machine1' unit='dbus-org.freedesktop.machine1.service'
Oct 25 17:06:26 localhost dbus[572]: [system] Successfully activated service 'org.freedesktop.machine1'
real 0m0.168s
user 0m0.003s
sys 0m0.016s
root@localhost:/home/vc/gh/systemd/build# echo 2 > /proc/sys/vm/drop_caches
root@localhost:/home/vc/gh/systemd/build# time ./systemctl --no-pager status dbus
● dbus.service - D-Bus System Message Bus
Loaded: loaded (/lib/systemd/system/dbus.service; static)
Active: active (running) since Sun 2020-10-25 17:03:05 PDT; 1 day 6h ago
TriggeredBy: ● dbus.socket
Docs: man:dbus-daemon(1)
Main PID: 572 (dbus-daemon)
Memory: 2.8M
CPU: 110ms
CGroup: /system.slice/dbus.service
└─572 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation
Oct 25 17:03:05 localhost systemd[1]: Started D-Bus System Message Bus.
Oct 25 17:06:26 localhost dbus[572]: [system] Activating via systemd: service name='org.freedesktop.machine1' unit='dbus-org.freedesktop.machine1.service'
Oct 25 17:06:26 localhost dbus[572]: [system] Successfully activated service 'org.freedesktop.machine1'
real 0m0.167s
user 0m0.005s
sys 0m0.013s
root@localhost:/home/vc/gh/systemd/build# echo 2 > /proc/sys/vm/drop_caches
root@localhost:/home/vc/gh/systemd/build# time ./systemctl --no-pager status dbus
● dbus.service - D-Bus System Message Bus
Loaded: loaded (/lib/systemd/system/dbus.service; static)
Active: active (running) since Sun 2020-10-25 17:03:05 PDT; 1 day 6h ago
TriggeredBy: ● dbus.socket
Docs: man:dbus-daemon(1)
Main PID: 572 (dbus-daemon)
Memory: 2.8M
CPU: 110ms
CGroup: /system.slice/dbus.service
└─572 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation
Oct 25 17:03:05 localhost systemd[1]: Started D-Bus System Message Bus.
Oct 25 17:06:26 localhost dbus[572]: [system] Activating via systemd: service name='org.freedesktop.machine1' unit='dbus-org.freedesktop.machine1.service'
Oct 25 17:06:26 localhost dbus[572]: [system] Successfully activated service 'org.freedesktop.machine1'
This adds minimal support for RFC5001 NSID to the stub resolver. This
useful to identify systemd-resolved when talking to the stub resolver,
and distuingishing the packets resolved answers itself (where NSID is
now set) from those which it proxies 1:1 upstream (where NSID will not
be set, or set to whatever the upstream server has it set to).
The NSID chosen consist of two parts:
1. The first part is derived from /etc/machine-id and identifies the
resolved instance in a stable way.
2. The second part is the fixed string ".resolved.systemd.io".
This thus maybe used for a veriety of checks:
a. Am I talking to a resolved stub?
b. Am I talking to the same stub as last time?
c. Am I talking to the local resolved?
Given that the first part leaks the identity of the system in away two
protections are in place:
I) The NSID is only included on the main stub, not the extra stub. The
main stub has with a TTL of 1 and other protections a lot of safety
in place that the datagrams never leave the local system, thus the
identifying info is only accessible to the local system — but
/etc/machine-id is accessible to local software anyway.
II) The NSID is hashed from /etc/machine-id in a non-invertable way, so
that the machine ID itself isn't leaked, but only an identifier
derived from it.
Add {Condition,Assert}CPUFeature to `systemd-analyze` & friends. Implement it
by executing the CPUID instruction. Add tables for common x86/i386
features.
Tested via unit tests + checked that commands such as:
Vito Caputo [Sun, 29 Nov 2020 00:28:08 +0000 (16:28 -0800)]
journal-file: fix archiving offline journals
The existing set_offline() short-circuit erroneously included
when f->archive was true and header->state was STATE_OFFLINE.
This commit makes the short-circuit f->archive aware, so it will
only catch scenarios where there's not an offlining in progress
and the header state matches the target state of either archived
or offline.
systemd: don't try to run as user manager when called without any arguments
It's better for users if programs don't do "significant" things too easily, and
should be especially conservative when called without any arguments whatsoever.
So far systemd would would try to launch itself as a user manager and fail on
some cgroup permission stuff. systemd --user is run execlusively from user@.service
and there we call it with --user. Calls to the binary without any arguments as
non-pid1 are almost always a mistake.
Joshua Watt [Fri, 30 Oct 2020 13:15:43 +0000 (08:15 -0500)]
logind: Restore chvt as non-root user without polkit
4acf0cfd2f ("logind: check PolicyKit before allowing VT switch") broke
the ability to write user sessions that run graphical sessions (e.g.
weston/X11). This was partially amended in 19bb87fbfa ("login: allow
non-console sessions to change vt") by changing the default PolicyKit
policy so that non-root users with a session are again allowed to switch
the VT. This makes the policy when PolKit is not enabled (as on many
embedded systems) closer the default PolKit policy and allows launching
graphical sessions as a non-root user.
Luca Boccassi [Mon, 18 Jan 2021 20:15:03 +0000 (20:15 +0000)]
stat-util: fix dir_is_empty_at without path
Use the right FD, and do a fd_reopen instead of a dup, since the
latter will still share the internal pointer which then gets
moved by FOREACH_DIRENT, affecting the caller's FD.
resolved: unify code for trying a different DNS server
Let's unify some code, and add a common implementation of a function
that checks whether we have tried all DNS servers yet, and retries the
transaction if we don't. We already use this same code twice. Let's use
it at some other places too now — basically all cases where we switch to
a new server — with the one case of packet loss, where we too switch
servers, but don#t care how many times we already tried to switch.
resolved: never go below DNSSEC feature level in DNSSEC strict mode
This adjusts our feature level handling: when DNSSEC strict mode is on,
let's never lower the feature level below the lowest DNSSEC mode.
Also, when asking whether DNSSEC is supproted, always say yes in strict
mode. This means that error reporting about transactions that fail
because of missing DNSSEC RRs will not report "incompatible-server" but
instead "missing-signature" or suchlike.
The main difference here is that DNSSEC failures become local to a
transaction, instead of propagating into the feature level we reuse for
future transactions. This is beneficial with routers that implement
"mostly a DNS proxy", i.e. that propagate most DNS requests 1:1 to their
upstream servers, but synthesize local answers for a select few domains.
For example, AVM Fritz!Boxes operate that way: they proxy most traffic
1:1 upstream in an DNSSEC-compatible fashion, but synthesize the
"fritz.box" locally, so that it can be used to configure the router.
This local domain cannot be DNSSEC verified, it comes without
signatures. Previously this would mean once that domain was resolved
feature level would be downgraded, and we'd thus fail all future DNSSEC
attempts. With this change, the immediate lookup for "fritz.box" will
fail validation, but for all other unrelated future ones that comes
without prejudice.
(While we are at it, also make a couple of other downgrade paths a bit
tighter.)
resolved: make feature level checks a bit more discriptive
The levels have an order, but the order is sometimes a bit arbitrary.
Hence add simple macros to check for specific features and use those, so
that the ordering leaks a bit less into all files.
resolved: when we can't parse a packet, downgrade feature level
So far we didn't really handle the case where we can't parse a reply
packet. Since this apparently happens in real-life though, let's add
some minimal logic, to downgrade/restart if we see this.
With all the preparatory work in previous PRs, we can now call static destructors
repeatedly without issue. We need to do it here so that global variables allocated
during parsing are properly freed.
tree-wide: reset the cleaned-up variable in cleanup functions
If the cleanup function returns the appropriate type, use that to reset the
variable. For other functions (usually the foreign ones which return void), add
an explicit value to reset to.
This causes a bit of code churn, but I think it might be worth it. In a
following patch static destructors will be called from a fuzzer, and this
change allows them to be called multiple times. But I think such a change might
help with detecting unitialized code reuse too. We hit various bugs like this,
and things are more obvious when a pointer has been set to NULL.
I was worried whether this change increases text size, but it doesn't seem to:
-Dbuildtype=debug:
before "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 4117672 Feb 16 14:36 build/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 4494520 Feb 16 15:06 build/systemd*
after "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 4117672 Feb 16 14:36 build/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 4494576 Feb 16 15:10 build/systemd*
now:
-rwxrwxr-x 1 zbyszek zbyszek 4117672 Feb 16 14:36 build/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 4494640 Feb 16 15:15 build/systemd*
-Dbuildtype=release:
before "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 5252256 Feb 14 14:47 build-rawhide/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 1834184 Feb 16 15:09 build-rawhide/systemd*
after "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 5252256 Feb 14 14:47 build-rawhide/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 1834184 Feb 16 15:10 build-rawhide/systemd*
now:
-rwxrwxr-x 1 zbyszek zbyszek 5252256 Feb 14 14:47 build-rawhide/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 1834184 Feb 16 15:16 build-rawhide/systemd*
I would expect that the compiler would be able to elide the setting of a
variable if the variable is never used again. And this seems to be the case:
in optimized builds there is no change in size whatsoever. And the change in
size in unoptimized build is negligible.
Something strange is happening with size of libsystemd: it's bigger in
optimized builds. Something to figure out, but unrelated to this patch.
I started working on this because I wanted to change how
DEFINE_TRIVIAL_CLEANUP_FUNC is defined. Even independently of that change, it's
nice to make make things more consistent and predictable.
resolved: let's preferably route reverse lookups for local subnets to matching interfaces
Let's preferably route traffic for reverse lookups to LLMNR/mDNS/DNS on
the matching interface if the IP address is in the local subnet. Also,
if looking up an IP address of our own host, let's avoid doing
LLMNR/mDNS at all.
This is useful if "~." is a routing domain to DNS, as it means, local
reverse lookups still go to LLMNR/mDNS, too.
Refactor strv_env_replace() into strv_env_replace_consume()
All callers of strv_env_replace() would free the argument on error.
So let's follow the same pattern as with strv_consume (and similar
naming) and unconditionally "use up" the argument.
Luca Boccassi [Thu, 28 Jan 2021 17:02:33 +0000 (17:02 +0000)]
namespace: store and use original MountEntry paths when prefixing
Some paths (eg: mount_tmpfs) simply assumed that prefixing always
happens and it always stores the original path in path_const, and
the prefixed path in path_malloc.
But if a MountEntry is set up in a helper function and thus uses
only _malloc struct members, this assumption doesn't hold and there's
a crash.
Refactor so that prefixing is done with a helper which stores the
original path in a separate struct member, and accessing it also
uses a helper which does the right thing.
resolved: make dns_transaction_gc return a pointer
_gc() does cleanup if it is possible. So far it returned a bool to
signal if it succeeded (false on success). When working on the resolved
code I had to look at the definition every time, because the (arguably
reversed) calling convention is unobvious. So let's return a pointer
(non-NULL: gc has not been done, NULL: gc has been done).
This fits nicely with the standard to return a pointer from all free
functions obviously.
The function to cleanup IPv6Token was defined using freep, i.e. the macro
generated a freepp function. The correct way would be to do something like
#define ipv6_token_free mfree
DEFINE_TRIVIAL_CLEANUP_FUNC(IPv6Token *, ipv6_token_free);
which would create ipv6_token_freep().
But since the cleanup function is unused, let's just drop it.
resolved: log process info of clients requesting resolution via D-Bus
Let's make things more debuggable: when debug logging is on, let's
say which client is asking for our services.
This is helpful for easily figuring out which local process might
interfere with your debugging sessions by issuing additional requests
while you try to debug a request (I am looking at you, geoclue!).
resolved: add "confidential" flag for replies passed to clients
Let's introduce a new flag that indicates whether the response was
acquired in "confidential" mode, i.e. via encrypted DNS-over-TLS, or
synthesized locally.
resolved: replace "answer_authenticated" bool by uint64_t query_flags field
Let's use the same flags type we use for client communication, i.e.
instead of "bool answer_authenticated", let's use "uint64_t
answer_query_flags", with the SD_RESOLVED_AUTHENTICATED flag.
This is mostly just search/replace, i.e. a refactoring, no change in
behaviour.
This becomes useful once in a later commit SD_RESOLVED_CONFIDENTIAL is
added to indicate resolution that either were encrypted (DNS-over-TLS)
or never left the local system.
resolvectl: clarify IDNA and search path logic in combination with "resolvectl query --type="
When low-level RR resolution is requested from "resolvectl query" via
"--type=" or "--class=" no search domain logic is applied and no IDNA
translation.
Explain this in detail in the documentation, and also mentions this when
users attempt to resolve single-label names or names with international
characters in the output.
I believe the current behaviour is correct, but it is indeed surprising.
Hence the documentation and output improvement.
fuzz-systemctl-parse-argv: avoid "leak" of bus object
Memory sanitizer would report leaked memory from --boot-load-entry=help.
Maybe we should disable all bus connections from the fuzzer? It seems not
appropriate to communicate with logind. OTOH, in a real fuzzing environment
this call should just fail, so maybe that's OK.
resolved: instead of closing DNS UDP transaction fds right-away, add them to a socket "graveyard"
The "socket graveyard" shall contain sockets we have sent a question out
of, but not received a reply. If we'd close thus sockets immediately
when we are not interested anymore, we'd trigger ICMP port unreachable
messages once we after all *do* get a reply. Let's avoid that, by
leaving the fds open for a bit longer, until a timeout is reached or a
reply datagram received.