The justification for RAND_pseudo_bytes is somewhat dubious, and the reality
is that it is frequently being misused. RAND_bytes and RAND_pseudo_bytes in
the default implementation both end up calling ssleay_rand_bytes. Both may
return -1 in an error condition. If there is insufficient entropy then
both will return 0, but RAND_bytes will additionally add an error to the
error queue. They both return 1 on success.
Therefore the fundamental difference between the two is that one will add an
error to the error queue with insufficient entory whilst the other will not.
Frequently there are constructions of this form:
if(RAND_pseudo_bytes(...) <= 1)
goto err;
In the above form insufficient entropy is treated as an error anyway, so
RAND_bytes is probably the better form to use.
This form is also seen:
if(!RAND_pseudo_bytes(...))
goto err;
This is technically not correct at all since a -1 return value is
incorrectly handled - but this form will also treat insufficient entropy as
an error.
Within libssl it is required that you have correctly seeded your entropy
pool and so there seems little benefit in using RAND_pseudo_bytes.
Similarly in libcrypto many operations also require a correctly seeded
entropy pool and so in most interesting cases you would be better off
using RAND_bytes anyway. There is a significant risk of RAND_pseudo_bytes
being incorrectly used in scenarios where security can be compromised by
insufficient entropy.
If you are not using the default implementation, then most engines use the
same function to implement RAND_bytes and RAND_pseudo_bytes in any case.
Given its misuse, limited benefit, and potential to compromise security,
RAND_pseudo_bytes has been deprecated.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Start ensuring all OpenSSL "free" routines allow NULL, and remove
any if check before calling them.
This gets DH_free, DSA_free, RSA_free
Reviewed-by: Matt Caswell <matt@openssl.org>
Disable loop checking when we retry verification with an alternative path.
This fixes the case where an intermediate CA is explicitly trusted and part
of the untrusted certificate list. By disabling loop checking for this case
the untrusted CA can be replaced by the explicitly trusted case and
verification will succeed.
Reviewed-by: Matt Caswell <matt@openssl.org>
If a set of certificates is supplied to OCSP_basic_verify use those in
addition to any present in the OCSP response as untrusted CAs when
verifying a certificate chain.
PR#3668
Reviewed-by: Matt Caswell <matt@openssl.org>
Move ASN.1 internals used across multiple directories into new internal
header file asn1_int.h remove crypto/Makefile hack which allowed other
directories to include "asn1_locl.h"
Reviewed-by: Matt Caswell <matt@openssl.org>
Start ensuring all OpenSSL "free" routines allow NULL, and remove
any if check before calling them.
This gets ASN1_OBJECT_free and ASN1_STRING_free.
Reviewed-by: Matt Caswell <matt@openssl.org>
Fix compilation failure when SCTP is compiled due to incorrect define.
Reported-by: Conrad Kostecki <ck+gentoobugzilla@bl4ckb0x.de>
URL: https://bugs.gentoo.org/543828
RT#3758
Signed-off-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Thanks to a -I.., the path does work, at least on unix. However, this
doesn't work so well on VMS. Correcting the path to not rely on given
-I does work on both.
Reviewed-by: Matt Caswell <matt@openssl.org>
Remove old ASN.1 COMPAT type. This was meant as a temporary measure
so older ASN.1 code (from OpenSSL 0.9.6) still worked. It's a hack
which breaks constification and hopefully nothing uses it now, if
it ever did.
Reviewed-by: Matt Caswell <matt@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>
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>
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_128_unwrap_raw() wrote to the output buffer ('ret'). This
means that OPENSSL_cleanse() could potentially write past the end of
'out'.
FIX: Change 'inlen' to 'ret' in the OPENSSL_cleanse() call.
- CRYPTO_128_unwrap() is returning the length of the input buffer
('inlen') instead of the number of bytes written to the output buffer
('ret'). This could cause the caller to read past the end of 'out'.
FIX: Return 'ret' instead of 'inlen' at the end of the function.
PR#3749
Reviewed-by: Stephen Henson <steve@openssl.org>
Reviewed-by: Emilia Käsper <emilia@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>
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>
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>
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>
Previously, ASN1_UTCTIME_cmp_time_t would return 1 if s > t, -1 if
s < t, and 0 if s == t.
This behavior was broken in a refactor [0], resulting in the opposite
time comparison behavior.
[0]: 904348a492
PR#3706
Reviewed-by: Stephen Henson <steve@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
Td4 and Te4 are arrays of u8. A u8 << int promotes the u8 to an int first then shifts.
If the mathematical result of a shift (as modelled by lhs * 2^{rhs}) is not representable
in an integer, behaviour is undefined. In other words, you can't shift into the sign bit
of a signed integer. Fix this by casting to u32 whenever we're shifting left by 24.
(For consistency, cast other shifts, too.)
Caught by -fsanitize=shift
Submitted by Nick Lewycky (Google)
Reviewed-by: Andy Polyakov <appro@openssl.org>
According to RFC 5649 section 4.1 step 1) we should not add padding
if plaintext length is multiply of 8 ockets.
This matches pseudo-code in http://dx.doi.org/10.6028/NIST.SP.800-38F
on page 15, section 6.3 KWP, algorithm 5 KWP-AE, step 2.
PR#3675
Reviewed-by: Stephen Henson <steve@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
Remove DECLARE_ASN1_SET_OF and DECLARE_PKCS12_STACK_OF these haven't been
used internally in OpenSSL for some time.
Reviewed-by: Rich Salz <rsalz@openssl.org>
When printing out an ASN.1 structure if the type is an item template don't
fall thru and attempt to interpret as a primitive type.
Reviewed-by: Andy Polyakov <appro@openssl.org>
