If the ASN.1 BIO is presented with a large length field read it in
chunks of increasing size checking for EOF on each read. This prevents
small files allocating excessive amounts of data.
CVE-2016-2109
Thanks to Brian Carpenter for reporting this issue.
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(cherry picked from commit c62981390d)
As it turns out branch hints grew as kind of a misconception. In
addition their interpretation by GNU assembler is affected by
assembler flags and can end up with opposite meaning on different
processors. As we have to loose quite a lot on misinterprerations,
especially on newer processors, we just omit them altogether.
Reviewed-by: Tim Hudson <tjh@openssl.org>
(cherry picked from commit 20b88bb160)
no-comp on Windows was not actually suppressing compilation of the code,
although it was suppressing its use.
Reviewed-by: Richard Levitte <levitte@openssl.org>
There is a potential double free in EVP_DigestInit_ex. This is believed
to be reached only as a result of programmer error - but we should fix it
anyway.
Issue reported by Guido Vranken.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit ffe9150b15)
Some OSes, *cough*-dows, insist on stack being "wired" to
physical memory in strictly sequential manner, i.e. if stack
allocation spans two pages, then reference to farmost one can
be punishable by SEGV. But page walking can do good even on
other OSes, because it guarantees that villain thread hits
the guard page before it can make damage to innocent one...
Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from commit adc4f1fc25)
Not all assemblers of "gas" flavour handle binary constants, e.g.
seasoned MacOS Xcode doesn't, so give them a hand.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(cherry picked from commit 6e42e3ff9c)
PVK files with abnormally large length or salt fields can cause an
integer overflow which can result in an OOB read and heap corruption.
However this is an rarely used format and private key files do not
normally come from untrusted sources the security implications not
significant.
Fix by limiting PVK length field to 100K and salt to 10K: these should be
more than enough to cover any files encountered in practice.
Issue reported by Guido Vranken.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from commit 5f57abe2b1)
and reorganize/harmonize post-conditions.
Additional hardening following on from CVE-2016-0702
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from master)
At the same time remove miniscule bias in final subtraction.
Performance penalty varies from platform to platform, and even with
key length. For rsa2048 sign it was observed to be 4% for Sandy
Bridge and 7% on Broadwell.
CVE-2016-0702
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from master)
Performance penalty is 2% on Linux and 5% on Windows.
CVE-2016-0702
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from master)
Performance penalty varies from platform to platform, and even
key length. For rsa2048 sign it was observed to reach almost 10%.
CVE-2016-0702
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from master)
Resolved conflicts:
crypto/bn/bn_exp.c
In the BN_hex2bn function the number of hex digits is calculated using
an int value |i|. Later |bn_expand| is called with a value of |i * 4|.
For large values of |i| this can result in |bn_expand| not allocating any
memory because |i * 4| is negative. This leaves ret->d as NULL leading
to a subsequent NULL ptr deref. For very large values of |i|, the
calculation |i * 4| could be a positive value smaller than |i|. In this
case memory is allocated to ret->d, but it is insufficiently sized
leading to heap corruption. A similar issue exists in BN_dec2bn.
This could have security consequences if BN_hex2bn/BN_dec2bn is ever
called by user applications with very large untrusted hex/dec data. This is
anticipated to be a rare occurrence.
All OpenSSL internal usage of this function uses data that is not expected
to be untrusted, e.g. config file data or application command line
arguments. If user developed applications generate config file data based
on untrusted data then it is possible that this could also lead to security
consequences. This is also anticipated to be a rare.
Issue reported by Guido Vranken.
CVE-2016-0797
Reviewed-by: Andy Polyakov <appro@openssl.org>
Even though AVX support was added in GAS 2.19 vpclmulqdq was apparently
added in 2.20.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from commit d3cdab1736)
This reverts commit 6656ba7152.
This broke existing engines that didn't properly implement the sign and verify
functions.
Reviewed-by: Richard Levitte <levitte@openssl.org>
MR: #2077
The internal |fmtstr| function used in processing a "%s" format string
in the BIO_*printf functions could overflow while calculating the length
of a string and cause an OOB read when printing very long strings.
Additionally the internal |doapr_outch| function can attempt to write to
an OOB memory location (at an offset from the NULL pointer) in the event of
a memory allocation failure. In 1.0.2 and below this could be caused where
the size of a buffer to be allocated is greater than INT_MAX. E.g. this
could be in processing a very long "%s" format string. Memory leaks can also
occur.
These issues will only occur on certain platforms where sizeof(size_t) >
sizeof(int). E.g. many 64 bit systems. The first issue may mask the second
issue dependent on compiler behaviour.
These problems could enable attacks where large amounts of untrusted data
is passed to the BIO_*printf functions. If applications use these functions
in this way then they could be vulnerable. OpenSSL itself uses these
functions when printing out human-readable dumps of ASN.1 data. Therefore
applications that print this data could be vulnerable if the data is from
untrusted sources. OpenSSL command line applications could also be
vulnerable where they print out ASN.1 data, or if untrusted data is passed
as command line arguments.
Libssl is not considered directly vulnerable. Additionally certificates etc
received via remote connections via libssl are also unlikely to be able to
trigger these issues because of message size limits enforced within libssl.
CVE-2016-0799
Issue reported by Guido Vranken.
Reviewed-by: Andy Polyakov <appro@openssl.org>
The SRP user database lookup method SRP_VBASE_get_by_user had confusing
memory management semantics; the returned pointer was sometimes newly
allocated, and sometimes owned by the callee. The calling code has no
way of distinguishing these two cases.
Specifically, SRP servers that configure a secret seed to hide valid
login information are vulnerable to a memory leak: an attacker
connecting with an invalid username can cause a memory leak of around
300 bytes per connection.
Servers that do not configure SRP, or configure SRP but do not configure
a seed are not vulnerable.
In Apache, the seed directive is known as SSLSRPUnknownUserSeed.
To mitigate the memory leak, the seed handling in SRP_VBASE_get_by_user
is now disabled even if the user has configured a seed.
Applications are advised to migrate to SRP_VBASE_get1_by_user. However,
note that OpenSSL makes no strong guarantees about the
indistinguishability of valid and invalid logins. In particular,
computations are currently not carried out in constant time.
Reviewed-by: Rich Salz <rsalz@openssl.org>
This is a partial revert of commit c8491de39 ("GH354: Memory leak fixes"),
which was cherry-picked from commit 55500ea7c in OpenSSL 1.1.
That commit introduced a change in behaviour which is a regression for
software implementing Microsoft Authenticode — which requires a PKCS#7
signature to be validated against explicit external data, even though
it's a non-detached signature with its own embedded data.
The is fixed differently in OpenSSL 1.1 by commit 6b2ebe433 ("Add
PKCS7_NO_DUAL_CONTENT flag"), but that approach isn't viable in the
1.0.2 stable branch, so just comment the offending check back out again.
Signed-off-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Fix double free bug when parsing malformed DSA private keys.
Thanks to Adam Langley (Google/BoringSSL) for discovering this bug using
libFuzzer.
CVE-2016-0705
Reviewed-by: Emilia Käsper <emilia@openssl.org>
It's never problem if CRYPTO_ctr128_encrypt is called from EVP, because
buffer in question is always aligned within EVP_CIPHER_CTX structure.
RT#4218
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit 5e4bbeb49f)
Also in X509_verify_cert() avoid using "i" not only as a loop
counter, but also as a trust outcome and as an error ordinal.
Finally, make sure that all "goto end" jumps return an error, with
"end" renamed to "err" accordingly.
[ The 1.1.0 version of X509_verify_cert() is major rewrite,
which addresses these issues in a more systemic way. ]
Reviewed-by: Rich Salz <rsalz@openssl.org>
Can't hurt and seems to prevent problems from some over-aggressive
(LTO?) compilers.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit 98ab57644f)
Add tests for have_precompute_mult for the optimised curves (nistp224,
nistp256 and nistp521) if present
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit 8ce4e7e605)
During precomputation if the group given is well known then we memcpy a
well known precomputation. However we go the wrong label in the code and
don't store the data properly. Consequently if we call have_precompute_mult
the data isn't there and we return 0.
RT#3600
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit 615614c886)
The function DH_check_pub_key() was missing some return value checks in
some calls to BN functions.
RT#4278
Reviewed-by: Andy Polyakov <appro@openssl.org>
(cherry picked from commit f5a12207ec)
A new return value for DH_check_pub_key was recently added:
DH_CHECK_PUBKEY_INVALID. As this is a flag which can be ORed with other
return values it should have been set to the value 4 not 3.
RT#4278
Reviewed-by: Andy Polyakov <appro@openssl.org>
(cherry picked from commit cb389fe804)
Following on from the previous commit, add a test to ensure that
DH_compute_key correctly fails if passed a bad y such that:
y^q (mod p) != 1
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Historically OpenSSL only ever generated DH parameters based on "safe"
primes. More recently (in version 1.0.2) support was provided for
generating X9.42 style parameter files such as those required for RFC
5114 support. The primes used in such files may not be "safe". Where an
application is using DH configured with parameters based on primes that
are not "safe" then an attacker could use this fact to find a peer's
private DH exponent. This attack requires that the attacker complete
multiple handshakes in which the peer uses the same DH exponent.
A simple mitigation is to ensure that y^q (mod p) == 1
CVE-2016-0701 (fix part 1 of 2)
Issue reported by Antonio Sanso.
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
- bugfix: should not treat '--' as invalid domain substring.
- '-' should not be the first letter of a domain
Signed-off-by: Viktor Dukhovni <viktor@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
Found by clang scan-build.
Signed-off-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Richard Levitte <levitte@openssl.org>
RT: #4184, MR: #1496
(cherry picked from commit 679d87515d)
BIO_int_ctrl isn't made for the purpose BIO_get_conn_int_port used it
for.
This also changes BIO_C_GET_CONNECT to actually return the port
instead of assigning it to a pointer that was never returned back to
the caller.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Some URLs in the source code ended up getting mangled by indent. This fixes
it. Based on a patch supplied by Arnaud Lacombe <al@aerilon.ca>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Commit 2b0180c37f attempted to do this but
only hit one of many BN_mod_exp codepaths. Fix remaining variants and add
a test for each method.
Thanks to Hanno Boeck for reporting this issue.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
(cherry picked from commit d911097d7c)
Avoid seg fault by checking mgf1 parameter is not NULL. This can be
triggered during certificate verification so could be a DoS attack
against a client or a server enabling client authentication.
Thanks to Loïc Jonas Etienne (Qnective AG) for discovering this bug.
CVE-2015-3194
Reviewed-by: Richard Levitte <levitte@openssl.org>
When parsing a combined structure pass a flag to the decode routine
so on error a pointer to the parent structure is not zeroed as
this will leak any additional components in the parent.
This can leak memory in any application parsing PKCS#7 or CMS structures.
CVE-2015-3195.
Thanks to Adam Langley (Google/BoringSSL) for discovering this bug using
libFuzzer.
PR#4131
Reviewed-by: Richard Levitte <levitte@openssl.org>
Thanks to Guido Vranken <guidovranken@gmail.com> for reporting this issue.
Reviewed-by: Tim Hudson <tjh@openssl.org>
(cherry picked from commit 158e5207a7)
Conflicts:
crypto/asn1/asn1_par.c
Strict ISO confirming C compilers only define __sun
Reviewed-by: Viktor Dukhovni <openssl-users@dukhovni.org>
RT #4144, MR #1353
(cherry picked from commit 3d32218812)
The problem remained unnoticed so far, because it's never called by default.
You have to craft OPENSSL_ppccap environment variable to trigger the problem.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit e4693b4e2a)
It was also found that stich performs suboptimally on AMD Jaguar, hence
execution is limited to XOP-capable and Intel processors.
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
(cherry picked from commit a5fd24d19b)
During work on a larger change in master a number of locations were
identified where return value checks were missing. This backports the
relevant fixes.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Don't mark a certificate as self signed if keyUsage is present and
certificate signing not asserted.
PR#3979
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit f51e5ed6b4)
RFC5753 requires that we omit parameters for AES key wrap and set them
to NULL for 3DES wrap. OpenSSL decrypt uses the received algorithm
parameters so can transparently handle either form.
Reviewed-by: Andy Polyakov <appro@openssl.org>
(cherry picked from commit 4ec36aff2a)
The function int_rsa_verify is an internal function used for verifying an
RSA signature. It takes an argument |dtype| which indicates the digest type
that was used. Dependant on that digest type the processing of the
signature data will vary. In particular if |dtype == NID_mdc2| and the
signature data is a bare OCTETSTRING then it is treated differently to the
default case where the signature data is treated as a DigestInfo (X509_SIG).
Due to a missing "else" keyword the logic actually correctly processes the
OCTETSTRING format signature first, and then attempts to continue and
process it as DigestInfo. This will invariably fail because we already know
that it is a bare OCTETSTRING.
This failure doesn't actualy make a real difference because it ends up at
the |err| label regardless and still returns a "success" result. This patch
just cleans things up to make it look a bit more sane.
RT#4076
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit dffe51091f)
It returns -1 on error, not 0.
Signed-off-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Rich Salz <rsalz@openssl.org>
MR #1231
(cherry picked from commit d6e92c0bd6)
BN_with_flags() will read the dest->flags to keep the BN_FLG_MALLOCED but
overwrites everything else.
Signed-off-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Rich Salz <rsalz@openssl.org>
MR #1231
(cherry picked from commit f92768e6f5)
Thanks to David Benjamin <davidben@google.com> for pointing them out.
Reviewed-by: Steve Henson <steve@openssl.org>
MR #1198
(cherry picked from commit 605236f6a8)
BUF_strndup was calling strlen through BUF_strlcpy, and ended up reading
past the input if the input was not a C string.
Make it explicitly part of BUF_strndup's contract to never read more
than |siz| input bytes. This augments the standard strndup contract to
be safer.
The commit also adds a check for siz overflow and some brief documentation
for BUF_strndup().
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit 110f7b37de)
If we use BIO_new_file(), on Windows it'll jump through hoops to work
around their unusual charset/Unicode handling. it'll convert a UTF-8
filename to UCS-16LE and attempt to use _wfopen().
If you use BIO_read_filename(), it doesn't do this. Shouldn't it be
consistent?
It would certainly be nice if SSL_use_certificate_chain_file() worked.
Also made BIO_C_SET_FILENAME work (rsalz)
Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Andy Polyakov <appro@openssl.org>
(cherry picked from commit ff03599a2f)
There are a couple of minor fixes here:
1) Handle the case when RegisterEventSource() fails (which it may for
various reasons) and do the work of logging the event only if it succeeds.
2) Handle the case when ReportEvent() fails and do our best in debug builds
to at least attempt somehow indicate that something has gone wrong. The
typical situation would be someone running tools like DbMon, DBWin32,
DebugView or just having the debugger attached. The intent is to make sure
that at least some data will be captured so that we can save hours and days
of debugging time.
3) Minor fix to change the MessageBox() flag to MB_ICONERROR. Though the
value of MB_ICONERROR is the same value as MB_ICONSTOP, the intent is
better conveyed by using MB_ICONERROR.
Testing performed:
1) Clean compilation for debug-VC-WIN32 and VC-WIN32.
2) Good test results (nmake -f ms\ntdll.mak test) for debug-VC-WIN32 and
VC-WIN32.
3) Stepped through relevant changes using WinDBG and exercised the impacted
code paths.
Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit 4cd94416a4)
There were some memory leaks in the creation of an SRP verifier (both on
successful completion and also on some error paths).
Reviewed-by: Emilia Käsper <emilia@openssl.org>
(cherry picked from commit bf95cde287)
In master we have the function OPENSSL_clear_free(x,y), which immediately
returns if x == NULL. In <=1.0.2 this function does not exist so we have to
do:
OPENSSL_cleanse(x, y);
OPENSSL_free(x);
However, previously, OPENSSL_cleanse did not check that if x == NULL, so
the real equivalent check would have to be:
if (x != NULL)
OPENSSL_cleanse(x, y);
OPENSSL_free(x);
It would be easy to get this wrong during cherry-picking to other branches
and therefore, for safety, it is best to just ensure OPENSSL_cleanse also
checks for NULL.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from commit 020d8fc83f)
Previously, the conversion would silently coerce to ASCII. Now, we error
out.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit b785504a10)
Rewrite EVP_DecodeUpdate.
In particular: reject extra trailing padding, and padding in the middle
of the content. Don't limit line length. Add tests.
Previously, the behaviour was ill-defined, and depended on the position
of the padding within the input.
In addition, this appears to fix a possible two-byte oob read.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Dr Stephen Henson <steve@openssl.org>
(cherry picked from commit 3cdd1e94b1)
Fix both the caller to error out on malloc failure, as well as the
eventual callee to handle a NULL gracefully.
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Avoid using cnid = 0, use NID_undef instead, and return early instead
of trying to find an instance of that in the subject DN.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit fffc2faeb2)
Initialize pointers in param id by the book (explicit NULL assignment,
rather than just memset 0).
In x509_verify_param_zero() set peername to NULL after freeing it.
In x509_vfy.c's internal check_hosts(), avoid potential leak of
possibly already non-NULL peername. This is only set when a check
succeeds, so don't need to do this repeatedly in the loop.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit a0724ef1c9)
The |z| value should be 0x04 not 0x02
RT#3838
Signed-off-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit 91d2728b38)
The NULL cipher case can't actually happen because we have no
EVP_PBE_CTL combinations where cipher_nid is -1 and keygen is
PKCS12_PBE_keyivgen. But make the code more obviously correct.
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit 394f7b6fcc)
- Pass in the right ciphertext length to ensure we're indeed testing
ciphertext corruption (and not truncation).
- Only test one mutation per byte to not make the test too slow.
- Add a separate test for truncated ciphertexts.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit 25d6b3401c)
Slightly modified from the original PR.
Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit a7e974c7be)
Don't dereference |d| when |top| is zero. Also test that various BIGNUM methods behave correctly on zero/even inputs.
Follow-up to b11980d79a
Reviewed-by: Rich Salz <rsalz@openssl.org>
Fix more potential leaks in X509_verify_cert()
Fix memory leak in ClientHello test
Fix memory leak in gost2814789 test
Fix potential memory leak in PKCS7_verify()
Fix potential memory leaks in X509_add1_reject_object()
Refactor to use "goto err" in cleanup.
Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
(cherry picked from commit 55500ea7c4)
If the seed value for dsa key generation is too short (< qsize),
return an error. Also update the documentation.
Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
(cherry picked from commit f00a10b897)
Part of RT 3997
Per Ben, just jump to common exit code.
Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit cc2829e664)
The function BN_MONT_CTX_set was assuming that the modulus was non-zero
and therefore that |mod->top| > 0. In an error situation that may not be
the case and could cause a seg fault.
This is a follow on from CVE-2015-1794.
Reviewed-by: Richard Levitte <levitte@openssl.org>
EC_KEY_set_public_key_affine_coordinates was using some variables that only
apply if OPENSSL_NO_EC2M is not defined.
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(cherry picked from commit 8d11b7c7ee)
This leaves behind files with names ending with '.iso-8859-1'. These
should be safe to remove. If something went wrong when re-encoding,
there will be some files with names ending with '.utf8' left behind.
Reviewed-by: Rich Salz <rsalz@openssl.org>
The function X509_verify_cert checks the value of |ctx->chain| at the
beginning, and if it is NULL then it initialises it, along with the value
of ctx->untrusted. The normal way to use X509_verify_cert() is to first
call X509_STORE_CTX_init(); then set up various parameters etc; then call
X509_verify_cert(); then check the results; and finally call
X509_STORE_CTX_cleanup(). The initial call to X509_STORE_CTX_init() sets
|ctx->chain| to NULL. The only place in the OpenSSL codebase where
|ctx->chain| is set to anything other than a non NULL value is in
X509_verify_cert itself. Therefore the only ways that |ctx->chain| could be
non NULL on entry to X509_verify_cert is if one of the following occurs:
1) An application calls X509_verify_cert() twice without re-initialising
in between.
2) An application reaches inside the X509_STORE_CTX structure and changes
the value of |ctx->chain| directly.
With regards to the second of these, we should discount this - it should
not be supported to allow this.
With regards to the first of these, the documentation is not exactly
crystal clear, but the implication is that you must call
X509_STORE_CTX_init() before each call to X509_verify_cert(). If you fail
to do this then, at best, the results would be undefined.
Calling X509_verify_cert() with |ctx->chain| set to a non NULL value is
likely to have unexpected results, and could be dangerous. This commit
changes the behaviour of X509_verify_cert() so that it causes an error if
|ctx->chain| is anything other than NULL (because this indicates that we
have not been initialised properly). It also clarifies the associated
documentation. This is a follow up commit to CVE-2015-1793.
Reviewed-by: Stephen Henson <steve@openssl.org>
This adds a test for CVE-2015-1793. This adds a new test file
verify_extra_test.c, which could form the basis for additional
verification tests.
Reviewed-by: Stephen Henson <steve@openssl.org>
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.
Patch provided by the BoringSSL project.
CVE-2015-1793
Reviewed-by: Stephen Henson <steve@openssl.org>
