Ensure that all functions have their return values checked where
appropriate. This covers all functions defined and called from within
libssl.

Reviewed-by: Richard Levitte <levitte@openssl.org>

Mark most functions returning a result defined in any libssl header file
with __owur to warn if they are used without checking the return value.
Use -DUNUSED_RETURN compiler flag with gcc to activate these warnings.
Some functions returning a result are skipped if it is common and valid to
use these functions without checking the return value.

Reviewed-by: Richard Levitte <levitte@openssl.org>

In order to receive warnings on unused function return values the flag
-DDEBUG_UNUSED must be passed to the compiler. This change adds that for the
--strict-warnings Configure option.

Reviewed-by: Richard Levitte <levitte@openssl.org>

Reviewed-by: Matt Caswell <matt@openssl.org>

Follow up on the earlier "Do not keep TABLE in version control".
Actually removing TABLE from version control was forgotten.

Reviewed-by: Matt Caswell <matt@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>

Reviewed-by: Matt Caswell <matt@openssl.org>

Remove {i2d,d2i}_ASN1_BOOLEAN.

Rewrite single occurrence of d2i_ASN1_BOOLEAN in asn1_parse2

Reviewed-by: Rich Salz <rsalz@openssl.org>

Remove old M_ASN1_ macros and replace any occurences with the corresponding
function.

Remove d2i_ASN1_bytes, d2i_ASN1_SET, i2d_ASN1_SET: no longer used internally.

Reviewed-by: Rich Salz <rsalz@openssl.org>

In cooperation with Ard Biesheuvel (Linaro) and Sami Tolvanen (Google).

Reviewed-by: Richard Levitte <levitte@openssl.org>

Using $t is an artifact from the earlier changes in Configure and was
unfortunately forgotten as is.

Reviewed-by: Stephen Henson <steve@openssl.org>

This tests the unwrap algorithm with an invalid key. The result should
be rejected without returning any plaintext.

Reviewed-by: Emilia Käsper <emilia@openssl.org>

Reviewed-by: Emilia Käsper <emilia@openssl.org>

crypto/modes/wrap128.c was heavily refactored to support AES Key Wrap
with Padding, and four bugs were introduced into CRYPTO_128_unwrap() at
that time:

- crypto_128_unwrap_raw()'s return value ('ret') is checked incorrectly,
  and the function immediately returns 'ret' in (almost) all cases.
  This makes the IV checking code later in the function unreachable, but
  callers think the IV check succeeded since CRYPTO_128_unwrap()'s
  return value is non-zero.

  FIX: Return 0 (error) if crypto_128_unwrap_raw() returned 0 (error).

- crypto_128_unwrap_raw() writes the IV to the 'got_iv' buffer, not to
  the first 8 bytes of the output buffer ('out') as the IV checking code
  expects.  This makes the IV check fail.

  FIX: Compare 'iv' to 'got_iv', not 'out'.

- The data written to the output buffer ('out') is "cleansed" if the IV
  check fails, but the code passes OPENSSL_cleanse() the input buffer
  length ('inlen') instead of the number of bytes that
  crypto_12...

Reviewed-by: Stephen Henson <steve@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>

Updated test/testssl script to include the new DTLS capability in ssltest.

Reviewed-by: Emilia Käsper <emilia@openssl.org>

Reviewed-by: Emilia Käsper <emilia@openssl.org>

Reviewed-by: Emilia Käsper <emilia@openssl.org>

Reviewed-by: Stephen Henson <steve@openssl.org>

Reported by the LibreSSL project as a follow on to CVE-2015-0209

Reviewed-by: Richard Levitte <levitte@openssl.org>

Resync NEWS with the latest version from 1.0.2

Reviewed-by: Richard Levitte <levitte@openssl.org>

Resync CHANGES with the latest version from 1.0.2.

Reviewed-by: Richard Levitte <levitte@openssl.org>

In PKCS#7, the ASN.1 content component is optional.
This typically applies to inner content (detached signatures),
however we must also handle unexpected missing outer content
correctly.

This patch only addresses functions reachable from parsing,
decryption and verification, and functions otherwise associated
with reading potentially untrusted data.

Correcting all low-level API calls requires further work.

CVE-2015-0289

Thanks to Michal Zalewski (Google) for reporting this issue.

Reviewed-by: Steve Henson <steve@openssl.org>

Fix segmentation violation when ASN1_TYPE_cmp is passed a boolean type. This
can be triggered during certificate verification so could be a DoS attack
against a client or a server enabling client authentication.

CVE-2015-0286

Reviewed-by: Richard Levitte <levitte@openssl.org>

If client auth is used then a server can seg fault in the event of a DHE
cipher being used and a zero length ClientKeyExchange message being sent
by the client. This could be exploited in a DoS attack.

CVE-2015-1787

Reviewed-by: Richard Levitte <levitte@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>

Fix a bug where invalid PSS parameters are not rejected resulting in a
NULL pointer exception. This can be triggered during certificate
verification so could be a DoS attack against a client or a server
enabling client authentication.

Thanks to Brian Carpenter for reporting this issues.

CVE-2015-0208

Reviewed-by: Tim Hudson <tjh@openssl.org>

CVE-2015-0287

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>

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 that can lead to a segmentation fault. Erorrs processing the initial
ClientHello can trigger this scenario. An example of such an error could
be that a DTLS1.0 only client is attempting to connect to a DTLS1.2 only
server.

CVE-2015-0207

Reviewed-by: Richard Levitte <levitte@openssl.org>

OpenSSL 1.0.2 introduced the "multiblock" performance improvement. This
feature only applies on 64 bit x86 architecture platforms that support AES
NI instructions. A defect in the implementation of "multiblock" can cause
OpenSSL's internal write buffer to become incorrectly set to NULL when
using non-blocking IO. Typically, when the user application is using a
socket BIO for writing, this will only result in a failed connection.
However if some other BIO is used then it is likely that a segmentation
fault will be triggered, thus enabling a potential DoS attack.

CVE-2015-0290

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>

Reviewed-by: Richard Levitte <levitte@openssl.org>

./config would translate -d into having the target get a 'debug-'
prefix, and then run './Configure LIST' to find out if such a
debugging target exists or not.

With the recent changes, the separate 'debug-foo' targets are
disappearing, and we're giving the normal targets debugging
capabilities instead.  Unfortunately, './config' wasn't changed to
match this new behavior.

This change introduces the arguments '--debug' and '--release' - the
latter just for orthogonality - to ./Configure, and ./config now
treats -d by adding '--debug' to the options for ./Configure.

Reviewed-by: Matt Caswell <matt@openssl.org>

Some miscellaneous removal of dead code from apps. Also fix an issue with
error handling with pkcs7.

Reviewed-by: Richard Levitte <levitte@openssl.org>

Some miscellaneous removal of dead code from lib crypto.

Reviewed-by: Richard Levitte <levitte@openssl.org>

In the probable_prime() function we behave slightly different if the number
of bits we are interested in is <= BN_BITS2 (the num of bits in a BN_ULONG).
As part of the calculation we work out a size_limit as follows:

    size_limit = (((BN_ULONG)1) << bits) - BN_get_word(rnd) - 1;

There is a problem though if bits == BN_BITS2. Shifting by that much causes
undefined behaviour. I did some tests. On my system BN_BITS2 == 64. So I
set bits to 64 and calculated the result of:

    (((BN_ULONG)1) << bits)

I was expecting to get the result 0. I actually got 1! Strangely this...

    (((BN_ULONG)0) << BN_BITS2)

...does equal 0! This means that, on my system at least, size_limit will be
off by 1 when bits == BN_BITS2.

This commit fixes the behaviour so that we always get consistent results.

Reviewed-by: Andy Polyakov <appro@openssl.org>

The function CRYPTO_128_unwrap_pad uses an 8 byte AIV (Alternative Initial
Value). The least significant 4 bytes of this is placed into the local
variable |ptext_len|. This is done as follows:

    ptext_len = (aiv[4] << 24) | (aiv[5] << 16) | (aiv[6] << 8) | aiv[7];

aiv[4] is an unsigned char, but (aiv[4] << 24) is promoted to a *signed*
int - therefore we could end up shifting into the sign bit and end up with
a negative value. |ptext_len| is a size_t (typically 64-bits). If the
result of the shifts is negative then the upper bits of |ptext_len| will
all be 1.

This commit fixes the issue by explicitly casting to an unsigned int.

Reviewed-by: Richard Levitte <levitte@openssl.org>

Passing a negative value for the "-time" option to s_time results in a seg
fault. This commit fixes it so that time has to be greater than 0.

Reviewed-by: Andy Polyakov <appro@openssl.org>

The function tls1_PRF counts the number of digests in use and partitions
security evenly between them. There always needs to be at least one digest
in use, otherwise this is an internal error. Add a sanity check for this.

Reviewed-by: Richard Levitte <levitte@openssl.org>

The function sk_zero is supposed to zero the elements held within a stack.
It uses memset to do this. However it calculates the size of each element
as being sizeof(char **) instead of sizeof(char *). This probably doesn't
make much practical difference in most cases, but isn't a portable
assumption.

Reviewed-by: Richard Levitte <levitte@openssl.org>

Move memory allocation failure checks closer to the site of the malloc in
dgst app. Only a problem if the debug flag is set...but still should be
fixed.

Reviewed-by: Tim Hudson <tjh@openssl.org>