If a server receives an unexpected ClientHello then we may or may not
accept it. Make sure all such decisions are made in the state machine
and not in the record layer. This also removes a disparity between the
TLS and the DTLS code. The TLS code was making this decision in the
record layer, while the DTLS code was making it later.
Finally it also solves a problem where a warning alert was being sent
during tls_setup_handshake() and the function was returning a failure
return code. This is problematic because it can be called from a
transition function - which we only allow fatal errors to occur in.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5190)
The new extension is like signature_algorithms, but only for the
signature *on* the certificate we will present to the peer (the
old signature_algorithms extension is still used for signatures that
we *generate*, i.e., those over TLS data structures).
We do not need to generate this extension, since we are the same
implementation as our X.509 stack and can handle the same types
of signatures, but we need to be prepared to receive it, and use the received
information when selecting what certificate to present.
There is a lot of interplay between signature_algorithms_cert and
signature_algorithms, since both affect what certificate we can
use, and thus the resulting signature algorithm used for TLS messages.
So, apply signature_algorithms_cert (if present) as a filter on what
certificates we can consider when choosing a certificate+sigalg
pair.
As part of this addition, we also remove the fallback code that let
keys of type EVP_PKEY_RSA be used to generate RSA-PSS signatures -- the
new rsa_pss_pss_* and rsa_pss_rsae_* signature schemes have pulled
the key type into what is covered by the signature algorithm, so
we should not apply this sort of compatibility workaround.
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5068)
Probably this is the CCS between the first and second ClientHellos. It
should be ignored.
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4435)
This just adds the various extension functions. More changes will be
required to actually use them.
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4435)
Although this is forbidden by all three(!) relevant specifications,
there seem to be multiple server implementations in the wild that
send it. Since we didn't check for unexpected extensions in any
given message type until TLS 1.3 support was added, our previous
behavior was to silently accept these extensions and pass them over
to the custom extension callback (if any). In order to avoid
regression of functionality, relax the check for "extension in
unexpected context" for this specific case, but leave the protocol
enforcment mechanism unchanged for other extensions and in other
extension contexts.
Leave a detailed comment to indicate what is going on.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4463)
We'd like the first bit of early_data and the ClientHello to go in the
same TCP packet if at all possible to enable things like TCP Fast Open.
Also, if you're only going to send one block of early data then you also
don't need to worry about TCP_NODELAY.
Fixes#4783
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4802)
Variables n, d, p are no longer there.
[skip ci]
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4894)
Flush following the CCS after an HRR. Only flush the HRR if middlebox
compat is turned off.
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4701)
Normally we flush immediately after writing the ClientHello. However if
we are going to write a CCS immediately because we've got early_data to
come, then we should move the flush until after the CCS.
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4701)
The CCS may be sent at different times based on whether or not we
sent an HRR earlier. In order to make that decision this commit
also updates things to make sure we remember whether an HRR was
used or not.
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4701)
Since we no longer do version negotiation during the processing of an HRR
we do not need the TLSv1.3 specific write transition for ClientHello
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4701)
The new ServerHello format is essentially now the same as the old TLSv1.2
one, but it must additionally include supported_versions. The version
field is fixed at TLSv1.2, and the version negotiation happens solely via
supported_versions.
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4701)
The check_fatal macro is supposed to only be called if we are already
expecting to be in the fatal state. The macro asserts that we are and
puts us into the fatal state if not.
This issue combined with the problem fixed in the previous commit meant
that the fuzzer detected a crash at a point in the processing when we
should have already been in the fatal state.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4847)
The recent SSL error overhaul left a case where an error occurs but
SSLfatal() is not called.
Credit to OSSfuzz for finding this issue.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4847)
The most likely explanation for us ending up at this point in the code
is that we were called by the user application incorrectly - so use an
appropriate error code.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4778)
Follow up from the conversion to use SSLfatal() in the state machine to
clean things up a bit more.
[extended tests]
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4778)
We shouldn't call SSLfatal() multiple times for the same error condition.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4778)
Sometimes at the top level of the state machine code we know we are
supposed to be in a fatal error condition. This commit adds some sanity
checks to ensure that SSLfatal() has been called.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4778)
This is an initial step towards using SSLfatal() everywhere. Initially in
this commit and in subsequent commits we focus on the state machine code.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4778)
Typically if a fatal error occurs three things need to happen:
- Put an error on the error queue
- Send an alert
- Put the state machine into the error state
Although all 3 of these things need to be done every time we hit a fatal
error the responsibilities for doing this are distributed throughout the
code. The place where the error goes on the queue, where the alert gets
sent and where the state machine goes into the error state are almost
invariably different. It has been a common pattern to pass alert codes up
and down the stack to get the alert information from the point in the code
where the error is detected to the point in the code where the alert gets
sent.
This commit provides an SSLfatal() macro (backed by an ossl_statem_fatal
function) that does all 3 of the above error tasks. This is largely a drop
in replacement for SSLerr, but takes a couple of extra parameters (the SSL
object, and an alert code).
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4778)
SNI needs to be consistent before we accept early_data. However a
server may choose to not acknowledge SNI. In that case we have to
expect that a client may send it anyway. We change the consistency
checks so that not acknowledging is treated more a like a "wild card",
accepting any SNI as being consistent.
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4738)
We can only send early_data if the SNI is consistent. However it is valid
for the client to set SNI and the server to not use it. This would still be
counted as consistent. OpenSSL client was being overzealous in this check
and disallowing this scenario.
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4738)
It's argued that /WX allows to keep better focus on new code, which
motivates its comeback...
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4721)