To quickly check out IKE_SAs and find associated CHILD_SAs, the
child_sa_manager stores relations between CHILD_SAs and IKE_SAs. It provides
CHILD_SA specific IKE_SA checkout functions wrapping the ike_sa_manager.
As we now use the same reqid for multiple CHILD_SAs with the same selectors,
having marks based on the reqid makes not that much sense anymore. Instead we
use unique marks that use a custom identifier. This identifier is reused during
rekeying, keeping the marks constant for any rule relying on it (for example
installed by updown).
This also simplifies handling of reqid allocation, as we do not have to query
the marks that is not yet assigned for an unknown reqid.
To reassign reqids where appropriate, we explicitly allocate or confirm them
centrally on the kernel-interface.
Currently the state is stored in the kernel-interface wrapper for all
backends, but we may add appropriate methods to each backend to implement
a custom reqid allocation logic, if required.
The kernel backend uses an inbound parameter these days, where it makes
no sense to pass the update flag. The kernel backend decides itself how
it handles SA installation based on the inbound flag.
While we can handle the first selector only in BEET mode in kernel-netlink,
passing the full list gives the backend more flexibility how to handle this
information.
The reqid is not strictly required, as we set the reqid with the update
call when installing the negotiated SA.
If we don't need a reqid at this stage, we can later allocate the reqid in
the kernel backend once the SA parameters have been fully negotaited. This
allows us to assign the same reqid for the same selectors to avoid conflicts
on backends this is necessary.
With the introduction of PT-TLS, we started sending TLS close notifies after
the application layer completes (7bbf7aa9). While this makes sense for TCP based
transports, it is not required in EAP methods. In EAP, handshake completion
can be directly signaled using the outer EAP-SUCCESS message. This also saves
one round-trip in the EAP exchange.
Windows 7/8 does not seem to like TLS close notifies at all in EAP, and either
stalls (EAP-TTLS) or disconnects (PEAP).
Fixes#556.
A type is returned only if upper layers successfully created a record, that is
returns NEED_MORE. If we do not check for the return value, we might check a
previous record or the uninitialized type variable and falsely reset the
sequence number.
While they usually are not included in a normal strongSwan build, the XPC
header indirectly defines these Mach types. To build charon-xpc, which uses
both XPC and strongSwan includes, we have to redefine these types.
On OS X 10.10, when installing a virtual IP on a tun device, there is a chance
that a RTM_IFANNOUNCE is sent before the IP is ready on that link when calling
getifaddrs(). As we don't get an RTM_NEWADDR event either, that race lets us
miss the virtual IP install event, failing the add_ip() call.
While our ASN.1 parser can't handle BER indefinite length encoding, the OpenSSL
backend can. Some PKCS#12 containers get encoded this way, so we should
support loading such files in the pem plugin.
To make accept/recvmsg cancelable, we wrap them with poll. As poll itself
does not honor pending cancellations when entering the function, we use our
variant that checks for pending cancellation requests before entering poll().
In recent ruby versions, extensions get built with -Wformat. As we use custom
printf specifiers, that does not work for us. As there does not seem to be a
reliable way to override -Wformat, we use a variable for the format string,
which prevents gcc from doing the -Wformat check in that particular situation.
While it was always documented as boolean setting, the option is currently
handled as integer value, for which yes/no values do not work. Instead the
default of TRUE is used for a no value.
The option has been moved a lot during the last years, and in some locations
was handled as bool, in some as integer. In the latest codebase it
congruently used integer, which is actually not what is documented and used
in testing.
Fixes#781.
Similar to the inbound rules, the ALE filter processes IP-in-IP packets for
outbound tunnel mode traffic. When using an outbound default-drop policy,
Windows does not allow connection initiation without these explicit rules.
When processing inbound tunnel mode packets, Windows decrypts packets and
filters them as IP-in-IP packets. We therefore require an ALE filter that
calls the FWPM_CALLOUT_IPSEC_INBOUND_TUNNEL_ALE_ACCEPT callout to allow them
when using a default-drop policy.
Without these rules, any outbound packet created an ALE state that allows
inbound packets as well. Processing inbound packets without any outbound
traffic fails without these rules.
As the underlying C functions, send/recv on ruby sockets are not guaranteed
to send/recv all requested bytes. Use wrapper functions to make sure we get
all bytes needed.
poll() may return POLLHUP or POLLNVAL for given file descriptors. To handle
these properly, we signal them to the EXCEPT watcher state, if registered. If
not, we call the read/write callbacks, so they can properly fail when trying
to read from or write to the file descriptor.
Replace relevant uses of select() by poll(). poll(2) avoids the difficulties
we have with more than 1024 open file descriptors, and seems to be fairly
portable.
Fixes#757.
If multiple sockets are ready, we previously preferred the IPv4 non-NAT socket
over others. To handle all with equal priority, use a round-robin selection.
Instead of allocating MTU-sized buffers for each packet, read to a stack buffer
and copy to an allocation of the actual packet size. While it requires an
additional copy on non-Apple platforms, this should make allocation more
efficient for small packets.
Introduces options to enable concurrent Netlink queries. While this does not
make much sense on vanilla Linux, this can help on third party stacks to
increase throughput if longer latencies are to expect. Netlink message
retransmission can be optionally enabled if transmission is unreliable.
Non-socket based IKE bypass policies and other tweaks bring better compatibility
to third party stacks using Netlink.
As some backends over unreliable transport do not cache response messages,
retransmissions due the loss of responses perform the operation again. Add an
option to ignore some errors arising from such duplicate operations.
Note: This approach can't distinguish between real EXIST/NOTFOUND errors
and packet failures, and therefore is a source of race conditions and can't
detect any of these errors actually happening. Therefore that behavior is
disabled by default, and can be enabled with the ignore_retransmit_errors
strongswan.conf option.
To properly distinguish between real and retransmission errors, a Netlink
backend should implement retransmission detection using sequence numbers.
The socket based IKE bypass policies are usually superior, but not supported
on all networking stacks. The port based variant uses global policies for the
UDP ports we have IKE sockets for.
As under vanilla Linux the kernel can't handle parallel dump queries and returns
EBUSY, it makes not much sense to use them. Disable parallel queries by default
to basically restore original behavior, improving performance.
Besides that it can improve throughput, it avoids a deadlock situation. If
all threads are busy, watcher will invoke the FD notification for NEWADDR
events itself. If the lock is held, it gets locked up. As watcher is not
dispatching anymore, it can't signal Netlink socket send() completion, and
the send() operation does not return and keeps the lock.
If the kernel can't execute a Netlink query because a different query is already
active, it returns EBUSY. As this can happen now as we support parallel queries,
retry on this error condition.
Instead of locking the socket exclusively to wait for replies, use watcher
to wait for and read in responses asynchronously. This allows multiple parallel
Netlink queries, which can significantly improve performance if the kernel
Netlink layer has longer latencies and supports parallel queries.
For vanilla Linux, parallel queries don't make much sense, as it usually returns
EBUSY for the relevant dump requests. This requires a retry, and in the end
makes queries more expensive under high load.
Instead of checking the Netlink message sequence number to detect multi-part
messages, this code now relies on the NLM_F_MULTI flag to detect them. This
has previously been avoided (by 1d51abb7). It is unclear if the flag did not
work correctly on very old Linux kernels, or if the flag was not used
appropriately by strongSwan. The flag seems to work just fine back to 2.6.18,
which is a kernel still in use by RedHat/CentOS 5.
Fixes handling of invalid policies in end entity certificates by not rejecting
the full certificate, but just invalidating the affected policy. Additionally
adds a bunch of unit tests for the constraints plugin, and some minor fixes
to the nameConstraints handling.
Currently we still reject CAs that use invalid policy mapping; we should accept
such certificates and just invalid affected policies in a next iteration.
Fixes#453.
While RFC 5280 is not very specific about the matching rules of subjectAltNames,
it has some examples how to match email and FQDN constraints. We try to follow
these examples, and restrict DNS names to subdomain matching and email to
full email, host or domain matching.
Instead of rejecting the certificate completely if a certificate has a policy
OID that is actually not allowed by the issuer CA, we accept it. However, the
certificate policy itself is still considered invalid, and is not returned
in the auth config resulting from trust chain operations.
A user must make sure to rely on the returned auth config certificate policies
instead of the policies contained in the certificate; even if the certificate
is valid, the policy OID itself in the certificate are not to be trusted
anymore.
Martin Willi