A common idiom in the codebase is:
if (p + len > limit)
{
return; /* Too long */
}
Where "p" points to some malloc'd data of SIZE bytes and
limit == p + SIZE
"len" here could be from some externally supplied data (e.g. from a TLS
message).
The rules of C pointer arithmetic are such that "p + len" is only well
defined where len <= SIZE. Therefore the above idiom is actually
undefined behaviour.
For example this could cause problems if some malloc implementation
provides an address for "p" such that "p + len" actually overflows for
values of len that are too big and therefore p + len < limit!
Issue reported by Guido Vranken.
CVE-2016-2177
Reviewed-by: Rich Salz <rsalz@openssl.org>
Per RFC 5246,
Note: this extension is not meaningful for TLS versions prior to 1.2.
Clients MUST NOT offer it if they are offering prior versions.
However, even if clients do offer it, the rules specified in [TLSEXT]
require servers to ignore extensions they do not understand.
Although second sentence would suggest that there would be no interop
problems in always offering the extension, WebRTC has reported issues
with Bouncy Castle on < TLS 1.2 ClientHellos that still include
signature_algorithms. See also
https://bugs.chromium.org/p/webrtc/issues/detail?id=4223
RT#4390
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Stephen Henson <steve@openssl.org>
(cherry picked from commit f7aa318552)
Conflicts:
ssl/ssl_locl.h
* Perform ALPN after the SNI callback; the SSL_CTX may change due to
that processing
* Add flags to indicate that we actually sent ALPN, to properly error
out if unexpectedly received.
* document ALPN functions
* unit tests
Backport of commit 817cd0d52f
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
If a call to EVP_DecryptUpdate fails then a memory leak could occur.
Ensure that the memory is freed appropriately.
Issue reported by Guido Vranken.
Reviewed-by: Richard Levitte <levitte@openssl.org>
It makes no sense to call the OCSP status callback if we are resuming a
session because no certificates will be sent.
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
If a server sends the status_request extension then it may choose
to send the CertificateStatus message. However this is optional.
We were treating it as mandatory and the connection was failing.
Thanks to BoringSSL for reporting this issue.
RT#4120
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
If the call to OBJ_find_sigid_by_algs fails to find the relevant NID then
we should set the NID to NID_undef.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit 330dcb09b2)
There are lots of calls to EVP functions from within libssl There were
various places where we should probably check the return value but don't.
This adds these checks.
Reviewed-by: Richard Levitte <levitte@openssl.org>
The function tls1_get_curvelist() has an explicit check to see if s->cert
is NULL or not. However the check appears *after* calling the tls1_suiteb
macro which derefs s->cert. In reality s->cert can never be NULL because
it is created in SSL_new(). If the malloc fails then the SSL_new call fails
and no SSL object is created.
Reviewed-by: Tim Hudson <tjh@openssl.org>
(cherry picked from commit 6329b6092b)
Conflicts:
ssl/t1_lib.c
Some extension handling functions were passing in a pointer to the start
of the data, plus the length in order to calculate the end, rather than
just passing in the end to start with. This change makes things a little
more readable.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
It is valid for an extension block to be present in a ClientHello, but to
be of zero length.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
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
The size of the SRP extension can never be negative (the variable
|size| is unsigned). Therefore don't check if it is less than zero.
RT#3862
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit 9c89d29083)
Also reorder preferences to prefer prime curves to binary curves, and P-256 to everything else.
The result:
$ openssl s_server -named_curves "auto"
This command will negotiate an ECDHE ciphersuite with P-256:
$ openssl s_client
This command will negotiate P-384:
$ openssl s_client -curves "P-384"
This command will not negotiate ECDHE because P-224 is disabled with "auto":
$ openssl s_client -curves "P-224"
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
Don't check that the curve appears in the list of acceptable curves for the
peer, if they didn't send us such a list (RFC 4492 does not require that the
extension be sent).
Reviewed-by: Emilia Käsper <emilia@openssl.org>
(cherry picked from commit b79d24101e)
Fix builds config'd with no-ec and no-ec2m. Technically this combination is
redundant - but the fix is straight forward. Fix from OpenWrt.
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
If a client renegotiates using an invalid signature algorithms extension
it will crash a server with a NULL pointer dereference.
Thanks to David Ramos of Stanford University for reporting this bug.
CVE-2015-0291
Reviewed-by: Tim Hudson <tjh@openssl.org>
Conflicts:
ssl/t1_lib.c
If SSL_check_chain is called with a NULL X509 object or a NULL EVP_PKEY
or the type of the public key is unrecognised then the local variable
|cpk| in tls1_check_chain does not get initialised. Subsequently an
attempt is made to deref it (after the "end" label), and a seg fault will
result.
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
(cherry picked from commit d813f9eb38)
This should be a one off operation (subsequent invokation of the
script should not move them)
This commit is for the 1.0.2 changes
Reviewed-by: Tim Hudson <tjh@openssl.org>
Sometimes it fails to format them very well, and sometimes it corrupts them!
This commit moves some particularly problematic ones.
Conflicts:
crypto/bn/bn.h
crypto/ec/ec_lcl.h
crypto/rsa/rsa.h
demos/engines/ibmca/hw_ibmca.c
ssl/ssl.h
ssl/ssl3.h
Reviewed-by: Tim Hudson <tjh@openssl.org>
indent will not alter them when reformatting comments
(cherry picked from commit 1d97c84351)
Conflicts:
crypto/bn/bn_lcl.h
crypto/bn/bn_prime.c
crypto/engine/eng_all.c
crypto/rc4/rc4_utl.c
crypto/sha/sha.h
ssl/kssl.c
ssl/t1_lib.c
Reviewed-by: Tim Hudson <tjh@openssl.org>
When parsing ClientHello clear any existing extension state from
SRP login and SRTP profile.
Thanks to Karthikeyan Bhargavan for reporting this issue.
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit 4f605ccb77)
Conflicts:
ssl/t1_lib.c
Odd-length lists should be rejected everywhere upon parsing. Nevertheless,
be extra careful and add guards against off-by-one reads.
Also, drive-by replace inexplicable double-negation with an explicit comparison.
Reviewed-by: Matt Caswell <matt@openssl.org>
The Supported Elliptic Curves extension contains a vector of NamedCurves
of 2 bytes each, so the total length must be even. Accepting odd-length
lists was observed to lead to a non-exploitable one-byte out-of-bounds
read in the latest development branches (1.0.2 and master). Released
versions of OpenSSL are not affected.
Thanks to Felix Groebert of the Google Security Team for reporting this issue.
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit 33d5ba8629)
once the ChangeCipherSpec message is received. Previously, the server would
set the flag once at SSL3_ST_SR_CERT_VRFY and again at SSL3_ST_SR_FINISHED.
This would allow a second CCS to arrive and would corrupt the server state.
(Because the first CCS would latch the correct keys and subsequent CCS
messages would have to be encrypted, a MitM attacker cannot exploit this,
though.)
Thanks to Joeri de Ruiter for reporting this issue.
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit e94a6c0ede)
This ensures that it's zeroed even if the SSL object is reused
(as in ssltest.c). It also ensures that it applies to DTLS, too.
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit a06cd5d056)
The supported signature algorithms extension needs to be processed before
the certificate to use is decided and before a cipher is selected (as the
set of shared signature algorithms supported may impact the choice).
Reviewed-by: Matt Caswell <matt@openssl.org>
Since SNI will typically switch the SSL_CTX structure to the one
corresponding to the appopriate server we need to parse custom
extensions using the switched SSL_CTX not the original one. This
is done by parsing custom extensions *after* SNI.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
CVE-2014-3513
This issue was reported to OpenSSL on 26th September 2014, based on an original
issue and patch developed by the LibreSSL project. Further analysis of the issue
was performed by the OpenSSL team.
The fix was developed by the OpenSSL team.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Support separate parse and add callback arguments.
Add new callback so an application can free extension data.
Change return value for send functions so < 0 is an error 0
omits extension and > 0 includes it. This is more consistent
with the behaviour of other functions in OpenSSL.
Modify parse_cb handling so <= 0 is an error.
Make SSL_CTX_set_custom_cli_ext and SSL_CTX_set_custom_cli_ext argument
order consistent.
NOTE: these changes WILL break existing code.
Remove (now inaccurate) in line documentation.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
(cherry picked from commit 33f653adf3)
Since sanity checks are performed for all custom extensions the
serverinfo checks are no longer needed.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
(cherry picked from commit 707b026d78)
Conflicts:
ssl/ssl3.h
ssl/t1_lib.c
Reject attempts to use extensions handled internally.
Add flags to each extension structure to indicate if an extension
has been sent or received. Enforce RFC5246 compliance by rejecting
duplicate extensions and unsolicited extensions and only send a
server extension if we have sent the corresponding client extension.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
(cherry picked from commit 28ea0a0c6a)
