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 [Wed, 6 May 2015 10:40:06 +0000 (11:40 +0100)]
Fix DTLS session resumption
The session object on the client side is initially created during
construction of the ClientHello. If the client is DTLS1.2 capable then it
will store 1.2 as the version for the session. However if the server is only
DTLS1.0 capable then when the ServerHello comes back the client switches to
using DTLS1.0 from then on. However the session version does not get
updated. Therefore when the client attempts to resume that session the
server throws an alert because of an incorrect protocol version.
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 [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.
Andy Polyakov [Wed, 20 May 2015 07:36:48 +0000 (09:36 +0200)]
bn/asm/x86_64-mont5.pl: fix valgrind error.
bn_get_bits5 was overstepping array boundary by 1 byte. It was exclusively
read overstep and data could not have been used. The only potential problem
would be if array happens to end on the very edge of last accesible page.
Andy Polyakov [Wed, 13 May 2015 20:19:59 +0000 (22:19 +0200)]
bn/asm/vis3-mont.pl: fix intermittent EC failures on SPARC T3.
BLKINIT optimization worked on T4, but for some reason appears "too
aggressive" for T3 triggering intermiitent EC failures. It's not clear
why only EC is affected...
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 [Fri, 22 May 2015 12:48:49 +0000 (13:48 +0100)]
Fix typo setting up certificate masks
The certificate masks are used to select which ciphersuite we are going to
use. The variables |emask_k| and |emask_a| relate to export grade key
exchange and authentication respecitively. The variables |mask_k| and
|mask_a| are the equivalent versions for non-export grade. This fixes an
instance where the two usages of export/non-export were mixed up. In
practice it makes little difference since it still works!
Matt Caswell [Fri, 22 May 2015 12:33:19 +0000 (13:33 +0100)]
Remove export static DH ciphersuites
Remove support for the two export grade static DH ciphersuites. These two
ciphersuites were newly added (along with a number of other static DH
ciphersuites) to 1.0.2. However the two export ones have *never* worked
since they were introduced. It seems strange in any case to be adding new
export ciphersuites, and given "logjam" it also does not seem correct to
fix them.
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.
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.
Matt Caswell [Mon, 4 May 2015 22:15:46 +0000 (23:15 +0100)]
Remove libcrypto to libssl dependency
Remove dependency on ssl_locl.h from v3_scts.c, and incidentally fix a build problem with
kerberos (the dependency meant v3_scts.c was trying to include krb5.h, but without having been
passed the relevanant -I flags to the compiler)
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.
Matt Caswell [Wed, 29 Apr 2015 12:22:18 +0000 (13:22 +0100)]
Fix buffer overrun in RSA signing
The problem occurs in EVP_PKEY_sign() when using RSA with X931 padding.
It is only triggered if the RSA key size is smaller than the digest length.
So with SHA512 you can trigger the overflow with anything less than an RSA
512 bit key. I managed to trigger a 62 byte overflow when using a 16 bit RSA
key. This wasn't sufficient to cause a crash, although your mileage may
vary.
In practice RSA keys of this length are never used and X931 padding is very
rare. Even if someone did use an excessively short RSA key, the chances of
them combining that with a longer digest and X931 padding is very
small. For these reasons I do not believe there is a security implication to
this. Thanks to Kevin Wojtysiak (Int3 Solutions) and Paramjot Oberoi (Int3
Solutions) for reporting this issue.
Matt Caswell [Wed, 29 Apr 2015 08:58:10 +0000 (09:58 +0100)]
Add sanity check to print_bin function
Add a sanity check to the print_bin function to ensure that the |off|
argument is positive. Thanks to Kevin Wojtysiak (Int3 Solutions) and
Paramjot Oberoi (Int3 Solutions) for reporting this issue.
Matt Caswell [Tue, 28 Apr 2015 14:28:23 +0000 (15:28 +0100)]
Add sanity check to ssl_get_prev_session
Sanity check the |len| parameter to ensure it is positive. Thanks to Kevin
Wojtysiak (Int3 Solutions) and Paramjot Oberoi (Int3 Solutions) for
reporting this issue.
Matt Caswell [Tue, 28 Apr 2015 14:19:50 +0000 (15:19 +0100)]
Sanity check the return from final_finish_mac
The return value is checked for 0. This is currently safe but we should
really check for <= 0 since -1 is frequently used for error conditions.
Thanks to Kevin Wojtysiak (Int3 Solutions) and Paramjot Oberoi (Int3
Solutions) for reporting this issue.
Matt Caswell [Mon, 27 Apr 2015 14:41:42 +0000 (15:41 +0100)]
Add sanity check in ssl3_cbc_digest_record
For SSLv3 the code assumes that |header_length| > |md_block_size|. Whilst
this is true for all SSLv3 ciphersuites, this fact is far from obvious by
looking at the code. If this were not the case then an integer overflow
would occur, leading to a subsequent buffer overflow. Therefore I have
added an explicit sanity check to ensure header_length is always valid.
Thanks to Kevin Wojtysiak (Int3 Solutions) and Paramjot Oberoi (Int3
Solutions) for reporting this issue.
Matt Caswell [Mon, 27 Apr 2015 14:41:03 +0000 (15:41 +0100)]
Clarify logic in BIO_*printf functions
The static function dynamically allocates an output buffer if the output
grows larger than the static buffer that is normally used. The original
logic implied that |currlen| could be greater than |maxlen| which is
incorrect (and if so would cause a buffer overrun). Also the original
logic would call OPENSSL_malloc to create a dynamic buffer equal to the
size of the static buffer, and then immediately call OPENSSL_realloc to
make it bigger, rather than just creating a buffer than was big enough in
the first place. Thanks to Kevin Wojtysiak (Int3 Solutions) and Paramjot
Oberoi (Int3 Solutions) for reporting this issue.
Matt Caswell [Mon, 27 Apr 2015 10:13:56 +0000 (11:13 +0100)]
Sanity check EVP_EncodeUpdate buffer len
There was already a sanity check to ensure the passed buffer length is not
zero. Extend this to ensure that it also not negative. Thanks to Kevin
Wojtysiak (Int3 Solutions) and Paramjot Oberoi (Int3 Solutions) for
reporting this issue.
Matt Caswell [Mon, 27 Apr 2015 10:07:06 +0000 (11:07 +0100)]
Sanity check EVP_CTRL_AEAD_TLS_AAD
The various implementations of EVP_CTRL_AEAD_TLS_AAD expect a buffer of at
least 13 bytes long. Add sanity checks to ensure that the length is at
least that. Also add a new constant (EVP_AEAD_TLS1_AAD_LEN) to evp.h to
represent this length. Thanks to Kevin Wojtysiak (Int3 Solutions) and
Paramjot Oberoi (Int3 Solutions) for reporting this issue.
Matt Caswell [Mon, 27 Apr 2015 10:04:56 +0000 (11:04 +0100)]
Sanity check DES_enc_write buffer length
Add a sanity check to DES_enc_write to ensure the buffer length provided
is not negative. Thanks to Kevin Wojtysiak (Int3 Solutions) and Paramjot
Oberoi (Int3 Solutions) for reporting this issue.
Matt Caswell [Wed, 29 Apr 2015 15:15:40 +0000 (16:15 +0100)]
Add length sanity check in SSLv2 n_do_ssl_write()
Fortify flagged up a problem in n_do_ssl_write() in SSLv2. Analysing the
code I do not believe there is a real problem here. However the logic flows
are complicated enough that a sanity check of |len| is probably worthwhile.
Thanks to Kevin Wojtysiak (Int3 Solutions) and Paramjot Oberoi (Int3
Solutions) for reporting this issue.
The above commit was backported to the 1.0.2 branch as part of backporting
the alternative chain verify algorithm changes. However it has been pointed
out (credit to Shigeki Ohtsu) that this is unnecessary in 1.0.2 as this
commit is a work around for loop checking that only exists in master.
Reviewed-by: Richard Levitte <levitte@openssl.org>