Tobias Brunner [Thu, 28 Jun 2018 16:47:15 +0000 (18:47 +0200)]
Merge branch 'ike-proposal-switch'
This allows switching the originally selected IKE config (based on the
IPs and IKE version) to a different one if no matching proposal is found.
This way we don't rely that much on the order of configs anymore and it's
possible to configure separate configs for clients that require weak
algorithms.
Tobias Brunner [Wed, 27 Jun 2018 15:59:54 +0000 (17:59 +0200)]
backend-manager: Change how IKE/peer config matches are logged
Instead of logging the search parameters for IKE configs (which were already
before starting the lookup) we log the configured settings.
The peer config lookup is also changed slightly by doing the IKE config
match first and skipping some checks if that or the local peer identity
doesn't match.
Tobias Brunner [Tue, 29 May 2018 16:12:16 +0000 (18:12 +0200)]
child-cfg: Allow suppressing log messages when selecting traffic selectors
Although being already logged on level 2, these messages are usually just
confusing if they pop up randomly in the log when e.g. querying the configs
or installing traps. So after this the log messages will only be logged when
actually proposing or selecting traffic selectors during IKE.
Tobias Brunner [Tue, 29 May 2018 15:04:12 +0000 (17:04 +0200)]
ike-init: Switch to an alternative config if proposals don't match
This way we don't rely on the order of equally matching configs as
heavily anymore (which is actually tricky in vici) and this also doesn't
require repeating weak algorithms in all configs that might potentially be
selected if there are some clients that require them.
There is currently no ordering, so an explicitly configured exactly matching
proposal isn't a better match than e.g. the default proposal that also
contains the proposed algorithms.
Tobias Brunner [Tue, 29 May 2018 14:57:49 +0000 (16:57 +0200)]
ike-auth: Consider negotiated IKE proposal when selecting peer configs
In some scenarios we might find multiple usable peer configs with different
IKE proposals. This is a problem if we use a config with non-matching
proposals that later causes IKE rekeying to fail. It might even be a problem
already when creating the CHILD_SA if the proposals of IKE and CHILD_SA
are consistent.
Tobias Brunner [Wed, 27 Jun 2018 12:31:50 +0000 (14:31 +0200)]
Merge branch 'settings-references'
This adds the ability to reference existing sections to the settings parser.
Mainly for swanctl.conf, where this could simplify complex configs a lot
as redundant information has only to be specified once and may then be
included in other sections (there is an example in the man page and
there are some in the unit tests).
Also added is a new setting in filelog sections to specify the path of
the log file (in case it contains characters that are not allowed in section
names). We should encourage people to configure their log files that way
which might allow use to prohibit dots in section names in the future.
Tobias Brunner [Tue, 15 May 2018 12:10:32 +0000 (14:10 +0200)]
settings: Add reference feature
Similar to the `also` keyword in ipsec.conf, the new syntax allows adding
one or more references to other sections, which means all the settings and
subsections defined there are inherited (values may be overridden, even
with an empty value to clear it).
It's important to note that all subsections are inherited, so if this is
used to reference a connection in swanctl.conf all auth rounds and
children are inherited. There is currently no syntax to limit the
inclusion level or clear inherited sections (but as mentioned, settings
in those inherited sections may be overridden).
Another property is that inherited settings or sections always follow
explicitly defined entries in the current section when they are enumerated.
This is relevant if the order is important (e.g. for auth rounds if `round`
is not specified).
References are evaluated dynamically at runtime, so referring to
sections later in the config file or included via other files is no
problem.
The colon used as separator to reference other sections may be used in
section names by writing :: (e.g. for Windows log file paths).
This is based on a patch originally written in 2016.
Tobias Brunner [Mon, 28 May 2018 17:09:02 +0000 (19:09 +0200)]
linked-list: Order of insert_before/remove_at calls doesn't matter anymore
This was quite confusing previously: While calling insert_before()
and then remove_at() properly replaced the current item, calling them the
other way around inserted the new item before the previous item because
remove_at() changed the enumerator's position to the previous item.
The behavior in corner cases (calling the methods before or after
enumeration) is also changed slightly.
Tobias Brunner [Tue, 22 May 2018 16:04:00 +0000 (18:04 +0200)]
ike-mobike: Always use this task for DPDs even if not behind a NAT
This allows switching to probing mode if the client is on a public IP
and this is the active task and connectivity gets restored. We only add
NAT-D payloads if we are currently behind a NAT (to detect changed NAT
mappings), a MOBIKE update that might follow will add them in case we
move behind a NAT.
Tobias Brunner [Fri, 1 Jun 2018 13:26:45 +0000 (15:26 +0200)]
testing: Print command output if test fails
This is quite helpful to debug why a pattern didn't match.
As it could produce quite a lot of output if something is not found in a
log file, the complete output is only printed in verbose mode, otherwise,
`head` is used to print the first 10 lines of output.
We only get stdout from SSH, so the stderr redirection is only really
for errors ssh itself produces.
Micah Morton [Fri, 8 Jun 2018 18:55:30 +0000 (11:55 -0700)]
Allow charon to change group on files before dropping caps
Allow charon to start as a non-root user without CAP_CHOWN and still be
able to change the group on files that need to be accessed by charon
after capabilities have been dropped. This requires the user charon starts
as to have access to socket/pidfile directory as well as belong to the
group that charon will run as after dropping capabilities.
Markus Sattler [Tue, 5 Jun 2018 06:20:52 +0000 (08:20 +0200)]
starter: Reset action before handling it
Stater will lose update/reload commands when there is a second signal
coming in when the previous is still processed. This can happen more
easily with big configurations.
Tobias Brunner [Mon, 19 Mar 2018 16:03:05 +0000 (17:03 +0100)]
ikev2: Initialize variable in case set_key() or allocate_bytes() fails
In case the PRF's set_key() or allocate_bytes() method failed, skeyseed
was not initialized and the chunk_clear() call later caused a crash.
This could have happened with OpenSSL in FIPS mode when MD5 was
negotiated (and test vectors were not checked, in which case the PRF
couldn't be instantiated as the test vectors would have failed).
MD5 is not included in the default proposal anymore since 5.6.1, so
with recent versions this could only happen with configs that are not
valid in FIPS mode anyway.
Tobias Brunner [Tue, 22 May 2018 08:13:59 +0000 (10:13 +0200)]
Merge branch 'ikesa-force-destroy'
Adds new options to force the local destruction of an IKE_SA (after
trying to send a DELETE first). This might be useful in situations where
it's known the other end is not reachable or already deleted the IKE_SA so
there is no point in retransmitting the DELETE and waiting for a response.
Martin Willi [Tue, 8 May 2018 13:06:33 +0000 (15:06 +0200)]
proposal: Add a compat alg for ChaCha20Poly1305 with explicit key length
The keylength fix for ChaCha20Poly1305 (5a7b0be2) removes the keylength
attribute from the AEAD transform. This breaks compatibility between
versions with the patch and those without. The ChaCha20Poly1305 AEAD
won't match in proposals between such versions, and if no other algorithm
is available, negotiating SAs fails.
As a migration strategy, this patch introduces a new string identifier for a
ChaCha20Poly1305 proposal keyword which uses the explicit keylength, exactly
as it was used before the mentioned patch. Administrators that care about
the use of that AEAD with old clients can temporarily add this keyword to
the list of proposals, until all clients have been upgraded.
The used approach is the least invasive, as it just adds an additional
keyword that can't do any harm if not explicitly configured. Nontheless
allows it the administrator to smoothly keep ChaCha20Poly1305 working,
even if upgrading all peers simultaneously is not an option. It requires
manual configuration edits, though, but we assume that ChaCha20Poly1305
is not that widely used, and not as the only transform in proposals.
Removing the compat keyword in a future version is an option; it might
be helpful for other implementations, though, that falsely use an
explicit key length in ChaCha20Poly1305 AEAD transforms.
kernel-netlink: Change how routes are un-/installed
We now check if there are other routes tracked for the same destination
and replace the installed route instead of just removing it. Same during
installation, where we previously didn't replace existing routes due to
NLM_F_EXCL. Routes with virtual IPs as source address are preferred over
routes without.
This should allow using trap policies with virtual IPs on Linux.
Tobias Brunner [Tue, 22 May 2018 07:52:08 +0000 (09:52 +0200)]
Merge branch 'cert-chain-fixes'
This fixes several issues that came up via BSI's Certification Path
Validation Test Tool (CPT):
1) In compliance with RFC 4945, section 5.1.3.2, we now enforce that a
certificate used for IKE authentication either does not contain a keyUsage
extension (like the ones produced by pki --issue) or that they include
digitalSignature or nonRepudiation.
2) CRLs that are not yet valid are now rejected as that could be a
problem in scenarios where expired certificates are removed from CRLs and
the clock on the host doing the revocation check is trailing behind that
of the host issuing CRLs.
3) Results other than revocation (e.g. a skipped check because the CRL
couldn't be fetched) are now stored also for intermediate CA certificates
and not only for end-entity certificates, so a strict CRL policy can be
enforced in such cases.
Tobias Brunner [Thu, 3 May 2018 09:07:59 +0000 (11:07 +0200)]
revocation: Also store validation results for intermediate CA certificates
If the certificate is revoked, we immediately returned and the chain was
invalid, however, if we couldn't fetch the CRL that result was not stored
for intermediate CAs and we weren't able to enforce a strict CRL policy
later.
Using such CRLs can be a problem if the clock on the host doing the
revocation check is trailing behind that of the host issuing CRLs in
scenarios where expired certificates are removed from CRLs. As revoked
certificates that expired will then not be part of new CRLs a host with
trailing clock might still accept such a certificate if it is still
valid according to its system clock but is not contained anymore in the
not yet valid CRL.
x509: Add flag that marks compliance with RFC 4945
According to RFC 4945, section 5.1.3.2, a certificate for IKE must
either not contain the keyUsage extension, or, if it does, have at least
one of the digitalSignature or nonReputiation bits set.
Tobias Brunner [Tue, 22 May 2018 07:44:51 +0000 (09:44 +0200)]
Merge branch 'dhcp-fixes'
Fixes some issues in the dhcp plugin like avoiding ICMP port unreachables
when setting a specific server address, or increasing the maximum size for
options e.g. for DNs in the client identifier option. The latter is also
only sent now if identity_lease is enabled (for most DHCP servers it
serves the same function as a unique MAC address does).
dhcp: Only send client identifier if identity_lease is enabled
The client identifier serves as unique identifier just like a unique MAC
address would, so even with identity_leases disabled some DHCP servers
might assign unique leases per identity.
dhcp: Increase maximum size of client identification option
This increases the chances that subject DNs that might have been cut
off with the arbitrary previous limit of 64 bytes might now be sent
successfully.
The REQUEST message has the most static overhead in terms of other
options (17 bytes) as compared to DISCOVER (5) and RELEASE (7).
Added to that are 3 bytes for the DHCP message type, which means we have
288 bytes left for the two options based on the client identity (host
name and client identification). Since both contain the same value, a
FQDN identity, which causes a host name option to get added, may be
142 bytes long, other identities like subject DNs may be 255 bytes
long (the maximum for a DHCP option).
dhcp: Increase buffer size for options in DHCP messages
According to RFC 2131, the minimum size of the 'options' field is 312
bytes, including the 4 byte magic cookie. There also does not seem to
be any restriction regarding the message length, previously the length
was rounded to a multiple of 64 bytes. The latter might have been
because in BOOTP the options field (or rather vendor-specific area as it
was called back then) had a fixed length of 64 bytes (so max(optlen+4, 64)
might actually have been what was intended), but for DHCP the field is
explicitly variable length, so I don't think it's necessary to pad it.
Since we won't read from the socket reducing the receive buffer saves
some memory and it should also minimize the impact on other processes that
bind the same port (Linux distributes packets to the sockets round-robin).
dhcp: Bind server port when a specific server address is specified
DHCP servers will respond to port 67 if giaddr is non-zero, which we set
if we are not broadcasting. While such messages are received fine via
RAW socket the kernel will respond with an ICMP port unreachable if no
socket is bound to that port. Instead of opening a dummy socket on port
67 just to avoid the ICMPs we can also just operate with a single
socket, bind it to port 67 and send our requests from that port.
Since SO_REUSEADDR behaves on Linux like SO_REUSEPORT does on other
systems we can bind that port even if a DHCP server is running on the
same host as the daemon (this might have to be adapted to make this work
on other systems, but due to the raw socket the plugin is not that portable
anyway).
Tobias Brunner [Fri, 16 Mar 2018 08:59:25 +0000 (09:59 +0100)]
dhcp: Fix destination port check in packet filter
The previous code compared the port in the packet to the client port and, if
successful, checked it also against the server port, which, therefore, never
matched, but due to incorrect offsets did skip the BPF_JA. If the client port
didn't match the code also skipped to the instruction after the BPF_JA.
However, the latter was incorrect also and processing would have continued at
the next instruction anyway. Basically, DHCP packets to any port were accepted.
What's not fixed with this is that the kernel returns an ICMP Port
unreachable for packets sent to the server port (67) because we don't
have a socket bound to it.
Fixes: f0212e8837b5 ("Accept DHCP replies on bootps port, as we act as a relay agent if server address configured")