The DSA code is deprecated and will, hopefully, be removed in the future.
Nonetheless, this is easy enough to fix. It's the analog of the work we'd
already done for ECDSA.
- Document more clearly that we don't care about the DSA code.
- Use the existing constant-time modular addition function rather than
the ad-hoc code.
- Reduce the digest to satisfy modular operations' invariants. (The
underlying algorithms could accept looser bounds, but we reduce for
simplicity.) There's no particular reason to do this in constant time,
but we have the code for it, so we may as well.
- This additionally adds a missing check that num_bits(q) is a multiple
of 8. We otherwise don't compute the right answer. Verification
already rejected all 160-, 224-, and 256-bit keys, and we only
generate DSA parameters where the length of q matches some hash
function's length, so this is unlikely to cause anyone trouble.
- Use Montgomery reduction to perform the modular multiplication. This
could be optimized to save a couple Montgomery reductions as in ECDSA,
but DSA is deprecated, so I haven't bothered optimizing this.
- The reduction from g^k (mod p) to r = g^k (mod p) (mod q) is left
in variable time, but reversing it would require a discrete log
anyway. (The corresponding ECDSA operation is much easier to make
constant-time due to Hasse's theorem, though that's actually still a
TODO. I need to finish lifting EC_FELEM up the stack.)
Thanks to Keegan Ryan from NCC Group for reporting the modular addition issue
(CVE-2018-0495). The remainder is stuff I noticed along the way.
Update-Note: See the num_bits(q) change.
Change-Id: I4f032b041e2aeb09f9737a39f178c24e6a7fa1cb
Reviewed-on: https://boringssl-review.googlesource.com/29145
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
With fixed-width BIGNUMs, this is no longer a concern. With this CL, I
believe we now no longer call BN_num_bits on BIGNUMs with secret
magnitude.
Of course, DSA then turns around and calls the variable-time BN_mod
immediately afterwards anyway. But the DSA is deprecated and doomed to
be removed someday anyway.
Change-Id: Iac1dab22aa51c0e7f5ca0f7f44a026a242a4eaa2
Reviewed-on: https://boringssl-review.googlesource.com/25284
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
These empty states aren't any use to either caller or implementor.
Change-Id: If0b748afeeb79e4a1386182e61c5b5ecf838de62
Reviewed-on: https://boringssl-review.googlesource.com/25254
Reviewed-by: Adam Langley <agl@google.com>
Although we are derived from 1.0.2, we mimic 1.1.0 in some ways around
our FOO_up_ref functions and opaque libssl types. This causes some
difficulties when porting third-party code as any OPENSSL_VERSION_NUMBER
checks for 1.1.0 APIs we have will be wrong.
Moreover, adding accessors without changing OPENSSL_VERSION_NUMBER can
break external projects. It is common to implement a compatibility
version of an accessor under #ifdef as a static function. This then
conflicts with our headers if we, unlike OpenSSL 1.0.2, have this
function.
This change switches OPENSSL_VERSION_NUMBER to 1.1.0 and atomically adds
enough accessors for software with 1.1.0 support already. The hope is
this will unblock hiding SSL_CTX and SSL_SESSION, which will be
especially useful with C++-ficiation. The cost is we will hit some
growing pains as more 1.1.0 consumers enter the ecosystem and we
converge on the right set of APIs to import from upstream.
It does not remove any 1.0.2 APIs, so we will not require that all
projects support 1.1.0. The exception is APIs which changed in 1.1.0 but
did not change the function signature. Those are breaking changes.
Specifically:
- SSL_CTX_sess_set_get_cb is now const-correct.
- X509_get0_signature is now const-correct.
For C++ consumers only, this change temporarily includes an overload
hack for SSL_CTX_sess_set_get_cb that keeps the old callback working.
This is a workaround for Node not yet supporting OpenSSL 1.1.0.
The version number is set at (the as yet unreleased) 1.1.0g to denote
that this change includes https://github.com/openssl/openssl/pull/4384.
Bug: 91
Change-Id: I5eeb27448a6db4c25c244afac37f9604d9608a76
Reviewed-on: https://boringssl-review.googlesource.com/10340
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
crypto/{asn1,x509,x509v3,pem} were skipped as they are still OpenSSL
style.
Change-Id: I3cd9a60e1cb483a981aca325041f3fbce294247c
Reviewed-on: https://boringssl-review.googlesource.com/19504
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
There are still a ton of them, almost exclusively complaints that
function declaration and definitions have different parameter names. I
just fixed a few randomly.
Change-Id: I1072f3dba8f63372cda92425aa94f4aa9e3911fa
Reviewed-on: https://boringssl-review.googlesource.com/18706
Reviewed-by: Steven Valdez <svaldez@google.com>
The only place it is used is EC_KEY_{dup,copy} and no one calls that
function on an EC_KEY with ex_data. This aligns with functions like
RSAPublicKey_dup which do not copy ex_data. The logic is also somewhat
subtle in the face of malloc errors (upstream's PR 3323).
In fact, we'd even changed the function pointer signature from upstream,
so BoringSSL-only code is needed to pass this pointer in anyway. (I
haven't switched it to CRYPTO_EX_unused because there are some callers
which pass in an implementation anyway.)
Note, in upstream, the dup hook is also used for SSL_SESSIONs when those
are duplicated (for TLS 1.2 ticket renewal or TLS 1.3 resumption). Our
interpretation is that callers should treat those SSL_SESSIONs
equivalently to newly-established ones. This avoids every consumer
providing a dup hook and simplifies the interface.
(I've gone ahead and removed the TODO(fork). I don't think we'll be able
to change this API. Maybe introduce a new one, but it may not be worth
it? Then again, this API is atrocious... I've never seen anyone use argl
and argp even.)
BUG=21
Change-Id: I6c9e9d5a02347cb229d4c084c1e85125bd741d2b
Reviewed-on: https://boringssl-review.googlesource.com/16344
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
BN_FLG_CONSTTIME is a ridiculous API and easy to mess up
(CVE-2016-2178). Instead, code that needs a particular algorithm which
preserves secrecy of some arguemnt should call into that algorithm
directly.
This is never set outside the library and is finally unused within the
library! Credit for all this goes almost entirely to Brian Smith. I just
took care of the last bits.
Note there was one BN_FLG_CONSTTIME check that was still reachable, the
BN_mod_inverse in RSA key generation. However, it used the same code in
both cases for even moduli and φ(n) is even if n is not a power of two.
Traditionally, RSA keys are not powers of two, even though it would make
the modular reductions a lot easier.
When reviewing, check that I didn't remove a BN_FLG_CONSTTIME that led
to a BN_mod_exp(_mont) or BN_mod_inverse call (with the exception of the
RSA one mentioned above). They should all go to functions for the
algorithms themselves like BN_mod_exp_mont_consttime.
This CL shows the checks are a no-op for all our tests:
https://boringssl-review.googlesource.com/c/12927/
BUG=125
Change-Id: I19cbb375cc75aac202bd76b51ca098841d84f337
Reviewed-on: https://boringssl-review.googlesource.com/12926
Reviewed-by: Adam Langley <alangley@gmail.com>
Instead, use BN_mod_exp_mont_consttime of p - 2. This removes two more
call sites sensitive to BN_FLG_CONSTTIME. We're down to just that last
BN_mod_inverse modulo φ(n). (Sort of. It's actually not sensitive
because even mod inverses always hit the other codepath. Perhaps we
should just leave it alone.)
Note this comes with a slight behavior change. The BN_MONT_CTXs are
initialized a little earlier. If a caller calls RSA_generate_* and then
reaches into the struct to scrap all the fields on it, they'll get
confused. Before, they had to perform an operation on it to get
confused. This is a completely ridiculous thing to do.
Since we do this a lot, this introduces some convenience functions for
doing the Fermat's Little Theorem mod inverse and fixes a leak in the
DSA code should computing kinv hit a malloc error.
BUG=125
Change-Id: Iafcae2fc6fd379d161f015c90ff7050e2282e905
Reviewed-on: https://boringssl-review.googlesource.com/12925
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Most C standard library functions are undefined if passed NULL, even
when the corresponding length is zero. This gives them (and, in turn,
all functions which call them) surprising behavior on empty arrays.
Some compilers will miscompile code due to this rule. See also
https://www.imperialviolet.org/2016/06/26/nonnull.html
Add OPENSSL_memcpy, etc., wrappers which avoid this problem.
BUG=23
Change-Id: I95f42b23e92945af0e681264fffaf578e7f8465e
Reviewed-on: https://boringssl-review.googlesource.com/12928
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
This gets cURL building against both BoringSSL as it is and BoringSSL
with OPENSSL_VERSION_NUMBER set to 1.1.0.
BUG=91
Change-Id: I5be73b84df701fe76f3055b1239ae4704a931082
Reviewed-on: https://boringssl-review.googlesource.com/10180
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
There are many cases where we need |BN_rand_range| but with a minimum
value other than 0. |BN_rand_range_ex| provides that.
Change-Id: I564326c9206bf4e20a37414bdbce16a951c148ce
Reviewed-on: https://boringssl-review.googlesource.com/8921
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
DSA is deprecated, but get this aligned with some of the BN_FLG_CONSTTIME work
going on elsewhere.
Change-Id: I676ceab298a69362bef1b61d6f597c5c90da2ff0
Reviewed-on: https://boringssl-review.googlesource.com/8309
Reviewed-by: Adam Langley <agl@google.com>
It's a prime, so computing a constant-time mod inverse is straight-forward.
Change-Id: Ie09b84363c3d5da827989300a844c470437fd8f2
Reviewed-on: https://boringssl-review.googlesource.com/8308
Reviewed-by: Adam Langley <agl@google.com>
Operations in the DSA signing algorithm should run in constant time in
order to avoid side channel attacks. A flaw in the OpenSSL DSA
implementation means that a non-constant time codepath is followed for
certain operations. This has been demonstrated through a cache-timing
attack to be sufficient for an attacker to recover the private DSA key.
CVE-2016-2178
(Imported from upstream's 621eaf49a289bfac26d4cbcdb7396e796784c534 and
b7d0f2834e139a20560d64c73e2565e93715ce2b.)
We should eventually not depend on BN_FLG_CONSTTIME since it's a mess (seeing
as the original fix was wrong until we reported b7d0f2834e to them), but, for
now, go with the simplest fix.
Change-Id: I9ea15c1d1cc3a7e21ef5b591e1879ec97a179718
Reviewed-on: https://boringssl-review.googlesource.com/8172
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
This reduces the chance of double-frees.
BUG=10
Change-Id: I11a240e2ea5572effeddc05acb94db08c54a2e0b
Reviewed-on: https://boringssl-review.googlesource.com/7583
Reviewed-by: David Benjamin <davidben@google.com>
This imports upstream's ea6b07b54c1f8fc2275a121cdda071e2df7bd6c1 along
with a bugfix in 987157f6f63fa70dbeffca3c8bc62f26e9767ff2.
In an SPKI, a DSA key is only an INTEGER, with the group information in
the AlgorithmIdentifier. But a standalone DSAPublicKey is more complex
(and apparently made up by OpenSSL). OpenSSL implemented this with a
write_params boolean and making DSAPublicKey a CHOICE.
Instead, have p_dsa_asn1.c encode an INTEGER directly. d2i_DSAPublicKey
only parses the standalone form. (That code will be replaced later, but
first do this in preparation for rewriting the DSA ASN.1 code.)
Change-Id: I6fbe298d2723b9816806e9c196c724359b9ffd63
Reviewed-on: https://boringssl-review.googlesource.com/7021
Reviewed-by: Adam Langley <agl@google.com>
C has implicit conversion of |void *| to other pointer types so these
casts are unnecessary. Clean them up to make the code easier to read
and to make it easier to find dangerous casts.
Change-Id: I26988a672e8ed4d69c75cfbb284413999b475464
Reviewed-on: https://boringssl-review.googlesource.com/7102
Reviewed-by: David Benjamin <davidben@google.com>
This callback is never used. The one caller I've ever seen is in Android
code which isn't built with BoringSSL and it was a no-op.
It also doesn't actually make much sense. A callback cannot reasonably
assume that it sees every, say, SSL_CTX created because the index may be
registered after the first SSL_CTX is created. Nor is there any point in
an EX_DATA consumer in one file knowing about an SSL_CTX created in
completely unrelated code.
Replace all the pointers with a typedef to int*. This will ensure code
which passes NULL or 0 continues to compile while breaking code which
passes an actual function.
This simplifies some object creation functions which now needn't worry
about CRYPTO_new_ex_data failing. (Also avoids bouncing on the lock, but
it's taking a read lock, so this doesn't really matter.)
BUG=391192
Change-Id: I02893883c6fa8693682075b7b130aa538a0a1437
Reviewed-on: https://boringssl-review.googlesource.com/6625
Reviewed-by: Adam Langley <agl@google.com>
This will allow a static linker (with -ffunction-sections since things aren't
split into files) to drop unused parts of DH and DSA. Notably, the parameter
generation bits pull in primality-checking code.
Change-Id: I25087e4cb91bc9d0ab43bcb267c2e2c164e56b59
Reviewed-on: https://boringssl-review.googlesource.com/6388
Reviewed-by: Adam Langley <agl@google.com>
CRYPTO_MUTEX_init needs a CRYPTO_MUTEX_cleanup. Also a pile of problems
with x509_lu.c I noticed trying to import some upstream change.
Change-Id: I029a65cd2d30aa31f4832e8fbfe5b2ea0dbc66fe
Reviewed-on: https://boringssl-review.googlesource.com/6346
Reviewed-by: Adam Langley <alangley@gmail.com>
This change converts the reference counts in crypto/ to use
|CRYPTO_refcount_t|. The reference counts in |X509_PKEY| and |X509_INFO|
were never actually used and so were dropped.
Change-Id: I75d572cdac1f8c1083c482e29c9519282d7fd16c
Reviewed-on: https://boringssl-review.googlesource.com/4772
Reviewed-by: Adam Langley <agl@google.com>
First batch of the alphabet.
Change-Id: If4e60f4fbb69e04eb4b70aa1b2240e329251bfa5
Reviewed-on: https://boringssl-review.googlesource.com/4514
Reviewed-by: Adam Langley <agl@google.com>
Instead, each module defines a static CRYPTO_EX_DATA_CLASS to hold the values.
This makes CRYPTO_cleanup_all_ex_data a no-op as spreading the
CRYPTO_EX_DATA_CLASSes across modules (and across crypto and ssl) makes cleanup
slightly trickier. We can make it do something if needbe, but it's probably not
worth the trouble.
Change-Id: Ib6f6fd39a51d8ba88649f0fa29c66db540610c76
Reviewed-on: https://boringssl-review.googlesource.com/4375
Reviewed-by: Adam Langley <agl@google.com>
This introduces a per-RSA/DSA/DH lock. This is good for lock contention,
although pthread locks are depressingly bloated.
Change-Id: I07c4d1606fc35135fc141ebe6ba904a28c8f8a0c
Reviewed-on: https://boringssl-review.googlesource.com/4324
Reviewed-by: Adam Langley <agl@google.com>
Beyond generally eliminating unnecessary includes, eliminate as many
includes of headers that declare/define particularly error-prone
functionality like strlen, malloc, and free. crypto/err/internal.h was
added to remove the dependency on openssl/thread.h from the public
openssl/err.h header. The include of <stdlib.h> in openssl/mem.h was
retained since it defines OPENSSL_malloc and friends as macros around
the stdlib.h functions. The public x509.h, x509v3.h, and ssl.h headers
were not changed in order to minimize breakage of source compatibility
with external code.
Change-Id: I0d264b73ad0a720587774430b2ab8f8275960329
Reviewed-on: https://boringssl-review.googlesource.com/4220
Reviewed-by: Adam Langley <agl@google.com>
Including string.h in base.h causes any file that includes a BoringSSL
header to include string.h. Generally this wouldn't be a problem,
although string.h might slow down the compile if it wasn't otherwise
needed. However, it also causes problems for ipsec-tools in Android
because OpenSSL didn't have this behaviour.
This change removes string.h from base.h and, instead, adds it to each
.c file that requires it.
Change-Id: I5968e50b0e230fd3adf9b72dd2836e6f52d6fb37
Reviewed-on: https://boringssl-review.googlesource.com/3200
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
DSA_verify and DSA_check_signature didn't share a codepath, so the fix was only
applied to the former. Implement verify in terms of check_signature and add
tests for bad DER variants.
Change-Id: I6577f96b13b57fc89a5308bd8a7c2318defa7ee1
Reviewed-on: https://boringssl-review.googlesource.com/2820
Reviewed-by: Adam Langley <agl@google.com>
By using non-DER or invalid encodings outside the signed portion of a
certificate the fingerprint can be changed without breaking the signature.
Although no details of the signed portion of the certificate can be changed
this can cause problems with some applications: e.g. those using the
certificate fingerprint for blacklists.
1. Reject signatures with non zero unused bits.
If the BIT STRING containing the signature has non zero unused bits reject the
signature. All current signature algorithms require zero unused bits.
2. Check certificate algorithm consistency.
Check the AlgorithmIdentifier inside TBS matches the one in the certificate
signature. NB: this will result in signature failure errors for some broken
certificates.
3. Check DSA/ECDSA signatures use DER.
Reencode DSA/ECDSA signatures and compare with the original received signature.
Return an error if there is a mismatch.
This will reject various cases including garbage after signature (thanks to
Antti Karjalainen and Tuomo Untinen from the Codenomicon CROSS program for
discovering this case) and use of BER or invalid ASN.1 INTEGERs (negative or
with leading zeroes).
CVE-2014-8275
(Imported from upstream's 85cfc188c06bd046420ae70dd6e302f9efe022a9 and
4c52816d35681c0533c25fdd3abb4b7c6962302d)
Change-Id: Ic901aea8ea6457df27dc542a11c30464561e322b
Reviewed-on: https://boringssl-review.googlesource.com/2783
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
Android requested that the wpa_supplicant go upstream. This change adds
some dummy functions and reinstates DSA_dup_DH in order to make the diff
smaller and easier for upstream.
Change-Id: I77ac271b8652bae5a0bbe16afde51d9096f3dfb5
Reviewed-on: https://boringssl-review.googlesource.com/1740
Reviewed-by: Adam Langley <agl@google.com>
Initial fork from f2d678e6e89b6508147086610e985d4e8416e867 (1.0.2 beta).
(This change contains substantial changes from the original and
effectively starts a new history.)
