Matt Caswell [Wed, 24 Jun 2015 14:55:36 +0000 (15:55 +0100)]
Fix alternate chains certificate forgery issue
During certificate verfification, OpenSSL will attempt to find an
alternative certificate chain if the first attempt to build such a chain
fails. An error in the implementation of this logic can mean that an
attacker could cause certain checks on untrusted certificates to be
bypassed, such as the CA flag, enabling them to use a valid leaf
certificate to act as a CA and "issue" an invalid certificate.
This occurs where at least one cert is added to the first chain from the
trust store, but that chain still ends up being untrusted. In that case
ctx->last_untrusted is decremented in error.
The PSK identity hint should be stored in the SSL_SESSION structure
and not in the parent context (which will overwrite values used
by other SSL structures with the same SSL_CTX).
Use BUF_strndup when copying identity as it may not be null terminated.
Richard Levitte [Sun, 21 Jun 2015 17:11:43 +0000 (19:11 +0200)]
Cleanup mttest.c : modernise output
Construct bio_err and bio_stdout from file handles instead of FILE
pointers, since the latter might not be implemented (when OPENSSL_NO_STDIO
is defined).
Convert all output to use BIO_printf.
Change lh_foo to lh_SSL_SESSION_foo.
It should not be possible for DTLS message fragments to span multiple
packets. However previously if the message header fitted exactly into one
packet, and the fragment body was in the next packet then this would work.
Obviously this would fail if packets get re-ordered mid-flight.
Matt Caswell [Thu, 4 Jun 2015 13:22:00 +0000 (14:22 +0100)]
EC_POINT_is_on_curve does not return a boolean
The function EC_POINT_is_on_curve does not return a boolean value.
It returns 1 if the point is on the curve, 0 if it is not, and -1
on error. Many usages within OpenSSL were incorrectly using this
function and therefore not correctly handling error conditions.
With thanks to the Open Crypto Audit Project for reporting this issue.
Matt Caswell [Thu, 30 Apr 2015 14:20:25 +0000 (15:20 +0100)]
Tighten extension handling
This adds additional checks to the processing of extensions in a ClientHello
to ensure that either no extensions are present, or if they are then they
take up the exact amount of space expected.
With thanks to the Open Crypto Audit Project for reporting this issue.
Reviewed-by: Stephen Henson <steve@openssl.org>
Conflicts:
ssl/t1_lib.c
Matt Caswell [Thu, 30 Apr 2015 13:51:10 +0000 (14:51 +0100)]
Fix memory leaks in BIO_dup_chain()
This fixes a memory leak that can occur whilst duplicating a BIO chain if
the call to CRYPTO_dup_ex_data() fails. It also fixes a second memory leak
where if a failure occurs after successfully creating the first BIO in the
chain, then the beginning of the new chain was not freed.
With thanks to the Open Crypto Audit Project for reporting this issue.
Reviewed-by: Stephen Henson <steve@openssl.org>
Conflicts:
crypto/bio/bio_lib.c
Matt Caswell [Thu, 30 Apr 2015 13:04:30 +0000 (14:04 +0100)]
Replace memset with OPENSSL_cleanse()
BUF_MEM_free() attempts to cleanse memory using memset immediately prior
to a free. This is at risk of being optimised away by the compiler, so
replace with a call to OPENSSL_cleanse() instead.
With thanks to the Open Crypto Audit Project for reporting this issue.
Richard Levitte [Tue, 9 Jun 2015 21:06:23 +0000 (23:06 +0200)]
When making libcrypto from apps or test, make sure to include engines
For librypto to be complete, the stuff in both crypto/ and engines/
have to be built. Doing 'make test' or 'make apps' from a clean
source tree failed to do so.
Corrected by using the new 'build_libcrypto' in the top Makefile.
Richard Levitte [Tue, 9 Jun 2015 23:34:26 +0000 (01:34 +0200)]
Add and rearrange building of libraries
There's a need for a target that will build all of libcrypto, so let's
add 'build_libcrypto' that does this. For ortogonality, let's also
add 'build_libssl'. Have both also depend on 'libcrypto.pc' and
'libssl.pc' so those get built together with the libraries.
This makes 'all' depend on fewer things directly.
Matt Caswell [Tue, 19 May 2015 12:59:47 +0000 (13:59 +0100)]
Fix off-by-one error in BN_bn2hex
A BIGNUM can have the value of -0. The function BN_bn2hex fails to account
for this and can allocate a buffer one byte too short in the event of -0
being used, leading to a one byte buffer overrun. All usage within the
OpenSSL library is considered safe. Any security risk is considered
negligible.
With thanks to Mateusz Kocielski (LogicalTrust), Marek Kroemeke and
Filip Palian for discovering and reporting this issue.
Matt Caswell [Mon, 18 May 2015 15:27:48 +0000 (16:27 +0100)]
Fix race condition in NewSessionTicket
If a NewSessionTicket is received by a multi-threaded client when
attempting to reuse a previous ticket then a race condition can occur
potentially leading to a double free of the ticket data.
CVE-2015-1791
This also fixes RT#3808 where a session ID is changed for a session already
in the client session cache. Since the session ID is the key to the cache
this breaks the cache access.
Matt Caswell [Mon, 9 Mar 2015 16:09:04 +0000 (16:09 +0000)]
Clear state in DTLSv1_listen
This is a backport of commit e83ee04bb7de800cdb71d522fa562e99328003a3 from
the master branch (and this has also been applied to 1.0.2). In 1.0.2 this
was CVE-2015-0207. For other branches there is no known security issue, but
this is being backported as a precautionary measure.
The DTLSv1_listen function is intended to be stateless and processes
the initial ClientHello from many peers. It is common for user code to
loop over the call to DTLSv1_listen until a valid ClientHello is received
with an associated cookie. A defect in the implementation of DTLSv1_listen
means that state is preserved in the SSL object from one invokation to the
next.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Matt Caswell [Fri, 29 May 2015 16:05:01 +0000 (17:05 +0100)]
Check the message type requested is the type received in DTLS
dtls1_get_message has an |mt| variable which is the type of the message that
is being requested. If it is negative then any message type is allowed.
However the value of |mt| is not checked in one of the main code paths, so a
peer can send a message of a completely different type and it will be
processed as if it was the message type that we were expecting. This has
very little practical consequences because the current behaviour will still
fail when the format of the message isn't as expected.
Matt Caswell [Mon, 25 May 2015 23:02:57 +0000 (00:02 +0100)]
Fix error check in GOST engine
The return value of i2d functions can be negative if an error occurs.
Therefore don't assign the return value to an unsigned type and *then*
check if it is negative.
Matt Caswell [Sat, 23 May 2015 20:51:21 +0000 (21:51 +0100)]
Don't send an alert if we've just received one
If the record received is for a version that we don't support, previously we
were sending an alert back. However if the incoming record already looks
like an alert then probably we shouldn't do that. So suppress an outgoing
alert if it looks like we've got one incoming.
Richard Levitte [Fri, 22 May 2015 15:54:06 +0000 (17:54 +0200)]
Fix the update target and remove duplicate file updates
We had updates of certain header files in both Makefile.org and the
Makefile in the directory the header file lived in. This is error
prone and also sometimes generates slightly different results (usually
just a comment that differs) depending on which way the update was
done.
This removes the file update targets from the top level Makefile, adds
an update: target in all Makefiles and has it depend on the depend: or
local_depend: targets, whichever is appropriate, so we don't get a
double run through the whole file tree.
Matt Caswell [Tue, 19 May 2015 15:03:02 +0000 (16:03 +0100)]
Fix off-by-one in BN_rand
If BN_rand is called with |bits| set to 1 and |top| set to 1 then a 1 byte
buffer overflow can occur. There are no such instances within the OpenSSL at
the moment.
Thanks to Mateusz Kocielski (LogicalTrust), Marek Kroemeke, Filip Palian for
discovering and reporting this issue.
Matt Caswell [Tue, 19 May 2015 14:19:30 +0000 (15:19 +0100)]
Reject negative shifts for BN_rshift and BN_lshift
The functions BN_rshift and BN_lshift shift their arguments to the right or
left by a specified number of bits. Unpredicatable results (including
crashes) can occur if a negative number is supplied for the shift value.
Thanks to Mateusz Kocielski (LogicalTrust), Marek Kroemeke and Filip Palian
for discovering and reporting this issue.
Matt Caswell [Tue, 27 Jan 2015 10:50:38 +0000 (10:50 +0000)]
Add -no_alt_chains option to apps to implement the new X509_V_FLAG_NO_ALT_CHAINS flag. Using this option means that when building certificate chains, the first chain found will be the one used. Without this flag, if the first chain found is not trusted then we will keep looking to see if we can build an alternative chain instead.
Reviewed-by: Dr. Stephen Henson <steve@openssl.org> Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Conflicts:
apps/cms.c
apps/ocsp.c
apps/s_client.c
apps/s_server.c
apps/smime.c
apps/verify.c
Matt Caswell [Tue, 27 Jan 2015 10:03:29 +0000 (10:03 +0000)]
In certain situations the server provided certificate chain may no longer be valid. However the issuer of the leaf, or some intermediate cert is in fact in the trust store.
When building a trust chain if the first attempt fails, then try to see if
alternate chains could be constructed that are trusted.
Emilia Kasper [Tue, 12 May 2015 14:10:05 +0000 (16:10 +0200)]
Update documentation with Diffie-Hellman best practices.
- Do not advise generation of DH parameters with dsaparam to save
computation time.
- Promote use of custom parameters more, and explicitly forbid use of
built-in parameters weaker than 2048 bits.
- Advise the callback to ignore <keylength> - it is currently called
with 1024 bits, but this value can and should be safely ignored by
servers.
Rich Salz [Tue, 12 May 2015 15:49:32 +0000 (11:49 -0400)]
Add NULL checks from master
The big "don't check for NULL" cleanup requires backporting some
of the lowest-level functions to actually do nothing if NULL is
given. This will make it easier to backport fixes to release
branches, where master assumes those lower-level functions are "safe"
This commit addresses those tickets: 3798 3799 3801.
Hanno Böck [Mon, 11 May 2015 10:33:37 +0000 (11:33 +0100)]
Call of memcmp with null pointers in obj_cmp()
The function obj_cmp() (file crypto/objects/obj_dat.c) can in some
situations call memcmp() with a null pointer and a zero length.
This is invalid behaviour. When compiling openssl with undefined
behaviour sanitizer (add -fsanitize=undefined to compile flags) this
can be seen. One example that triggers this behaviour is the pkcs7
command (but there are others, e.g. I've seen it with the timestamp
function):
apps/openssl pkcs7 -in test/testp7.pem
What happens is that obj_cmp takes objects of the type ASN1_OBJECT and
passes their ->data pointer to memcmp. Zero-sized ASN1_OBJECT
structures can have a null pointer as data.
Matt Caswell [Wed, 6 May 2015 20:31:16 +0000 (21:31 +0100)]
Don't allow a CCS when expecting a CertificateVerify
Currently we set change_cipher_spec_ok to 1 before calling
ssl3_get_cert_verify(). This is because this message is optional and if it
is not sent then the next thing we would expect to get is the CCS. However,
although it is optional, we do actually know whether we should be receiving
one in advance. If we have received a client cert then we should expect
a CertificateVerify message. By the time we get to this point we will
already have bombed out if we didn't get a Certificate when we should have
done, so it is safe just to check whether |peer| is NULL or not. If it is
we won't get a CertificateVerify, otherwise we will. Therefore we should
change the logic so that we only attempt to get the CertificateVerify if
we are expecting one, and not allow a CCS in this scenario.
Whilst this is good practice for TLS it is even more important for DTLS.
In DTLS messages can be lost. Therefore we may be in a situation where a
CertificateVerify message does not arrive even though one was sent. In that
case the next message the server will receive will be the CCS. This could
also happen if messages get re-ordered in-flight. In DTLS if
|change_cipher_spec_ok| is not set and a CCS is received it is ignored.
However if |change_cipher_spec_ok| *is* set then a CCS arrival will
immediately move the server into the next epoch. Any messages arriving for
the previous epoch will be ignored. This means that, in this scenario, the
handshake can never complete. The client will attempt to retransmit
missing messages, but the server will ignore them because they are the wrong
epoch. The server meanwhile will still be waiting for the CertificateVerify
which is never going to arrive.
Matt Caswell [Thu, 23 Apr 2015 19:01:33 +0000 (20:01 +0100)]
Add Error state
Reusing an SSL object when it has encountered a fatal error can
have bad consequences. This is a bug in application code not libssl
but libssl should be more forgiving and not crash.
Richard Levitte [Mon, 4 May 2015 15:34:40 +0000 (17:34 +0200)]
RT2943: Check sizes if -iv and -K arguments
RT2943 only complains about the incorrect check of -K argument size,
we might as well do the same thing with the -iv argument.
Before this, we only checked that the given argument wouldn't give a
bitstring larger than EVP_MAX_KEY_LENGTH. we can be more precise and
check against the size of the actual cipher used.