While I'm here, use a fixed-size uint64_t in RSA_generate_key, rather
than unsigned long. This code also assumes unsigned long fits in
BN_ULONG, which is probably true on all platforms we care about, but
unnecessarily fussy.
The RSA_sign -> RSA_METHOD transition does require a cast. Go ahead and
check length/hash_nid consistency so we know it fits in the cast. This
does mean RSA_METHOD-backed keys are restricted to implementing digests
that we support, but that's probably fine. If anything, I think we
should try to shift away from RSA_METHOD as a story for custom keys.
Bug: 516
Change-Id: I3969da67d1daeff882279a534eb48ca831eb16cd
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/54465
Commit-Queue: Bob Beck <bbe@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
This is far from all of it, but finishes a good chunk of bcm.c.
Bug: 516
Change-Id: If764e5af1c6b62e8342554502ecc4d563e44bc50
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/54207
Reviewed-by: Bob Beck <bbe@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Splitting this out from most of the -Wshorten-64-to-32 fixes since it
non-trivially rewrites the function. While I'm here, move variable
declarations slightly closer to their use and document how the salt
check differs from the spec.
Bug: 516
Change-Id: I2e53afecb8ba720fd8c02da504b56c829c20c93b
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/54206
Commit-Queue: David Benjamin <davidben@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
The C11 change has survived for three months now. Let's start freely
using static_assert. In C files, we need to include <assert.h> because
it is a macro. In C++ files, it is a keyword and we can just use it. (In
MSVC C, it is actually also a keyword as in C++, but close enough.)
I moved one assert from ssl3.h to ssl_lib.cc. We haven't yet required
C11 in our public headers, just our internal files.
Change-Id: Ic59978be43b699f2c997858179a9691606784ea5
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/53665
Auto-Submit: David Benjamin <davidben@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
This is cribbed, with perimssion, from AWS-LC. The FIPS service
indicator[1] signals when an approved service has been completed.
[1] FIPS 140-3 IG 2.4.C
Change-Id: Ib40210d69b3823f4d2a500b23a1606f8d6942f81
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/52568
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
fips_break_test.h is a bad name because generate_build_files.py thinks
that it's a test file, which it is, but one that's needed in the main
build. Thanks to Svilen Kanev for noting this.
That header doesn't particularly carry its weight. The idea was that
rebuilding the break test wouldn't need to rebuild everything if that
logic was isolated in its own header. But we only have to rebuild once
now, so whatever. There's already a block of crypto/internal.h with very
similar stuff; it can go there.
Change-Id: Ifb479eafd4df9a7aac4804cae06ba87257c77fc3
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/51485
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
FIPS validation requires showing that the continuous and start-up tests
are effective by breaking them. Traditionally BoringSSL used #defines
that tweaked the expected values. However, 140-3 now requires that the
inputs be changed, not the expected outputs.
Also, the number of tests is going to increase. Since slower platforms
already took too long to compile BoringSSL n times (once for each test
to break) we want something faster too.
Therefore all the known-answer tests (KATs) are changed such that a Go
program can find and replace the input value in order to break them.
Thus we only need to recompile once to disable the integrity test.
The runtime tests still need a #define to break, but that #define is now
put in a header file so that only the module need be recompiled, not
everything as in the previous system.
Change-Id: Ib621198e6ad02253e29af0ccd978e3c3830ad54c
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/51329
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
OpenSSL 1.1.0 made this structure opaque. I don't think we particularly
need to make it opaque, but external code uses it. Also add
RSA_test_flags.
Change-Id: I136d38e72ec4664c78f4d1720ec691f5760090c1
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/50605
Reviewed-by: Adam Langley <agl@google.com>
The bulk of RSA_check_key is spent in bn_div_consttime, which is a naive
but constant-time long-division algorithm for the few places that divide
by a secret even divisor: RSA keygen and RSA import. RSA import is
somewhat performance-sensitive, so pick some low-hanging fruit:
The main observation is that, in all but one call site, the bit width of
the divisor is public. That means, for an N-bit divisor, we can skip the
first N-1 iterations of long division because an N-1-bit remainder
cannot exceed the N-bit divisor.
One minor nuisance is bn_lcm_consttime, used in RSA keygen has a case
that does *not* have a public bit width. Apply the optimization there
would leak information. I've implemented this as an optional public
lower bound on num_bits(divisor), which all but that call fills in.
Before:
Did 5060 RSA 2048 private key parse operations in 1058526us (4780.2 ops/sec)
Did 1551 RSA 4096 private key parse operations in 1082343us (1433.0 ops/sec)
After:
Did 11532 RSA 2048 private key parse operations in 1084145us (10637.0 ops/sec) [+122.5%]
Did 3542 RSA 4096 private key parse operations in 1036374us (3417.7 ops/sec) [+138.5%]
Bug: b/192484677
Change-Id: I893ebb8886aeb8200a1a365673b56c49774221a2
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/49106
Reviewed-by: Adam Langley <agl@google.com>
We usually call the parameter 'digest', but people sometimes think they
can skip the hashing for short inputs are short. I also suspect the term
'digest' is less common. Add warnings about this.
There were also some cases where we called it 'in' and even 'msg'. This
CL fixes those to say 'digest'. Finally, RSA_{sign,verify}_raw are
documented to be building blocks of signature schemes, rather than
signature schemes themselves.
It's unfortunate that EVP_PKEY_sign means "sign a digest", while
EVP_DigestSign means "sign, likely internally digesting it as the first
step", but we're a bit stuck there.
Change-Id: I4c38afff9b6196e2789cf27653fe5e5e8c68c1bf
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47504
Reviewed-by: Adam Langley <agl@google.com>
https://boringssl-review.googlesource.com/c/boringssl/+/42504 aligned
RSA private key checks, but I missed the public key ones. We have two
different sets of RSA public key checks right now. One in the parser
just checks for e = 1 and even e. The other, when using the key, checks
for overly large e and n.
Align the two. Now parsing RSA public keys calls RSA_check_key and the
extra checks on e are added to RSA_check_key. Note RSA private key
parsing already called RSA_check_key. The consequences are:
First, RSA public keys with large n, large e, or n < e will be rejected
at parse time. Previously, they would be parsed but all operations on
them would fail. This aligns with our existing behavior for parsing
private keys.
Second, operations on RSA public keys with even e will fail. They
already failed to parse, but it was possible to manually construct such
a key. Previously, operations wouldn't explicitly fail, but they
wouldn't do anything useful because even exponents are not invertible.
(Encrypting would produce something undecryptable and the private key
would have a hard time reliably producing signatures we'd accept.) There
is no change to RSA private keys with even e. Those would already fail
the (e, d) consistency check and the fault check.
Third, operations on RSA public keys with e = 1 will fail. They already
failed to parse, but it was possible to manually construct such a key
and "verify" signatures or "encrypt" messages. However, with e = 1,
those operations are no-ops.
Finally, RSA private keys with e = d = 1 will be rejected at parse and
use. This is the only case that affects private keys because e = d = 1
are inverses, just pointless. Uses paired with RSA public key parsing
(e.g. our TLS library checks consistency with a certificate public key)
are not affected. Those already rejected such keys because we rejected
them in the public key parser. This CL aligns the private half.
This doesn't close https://crbug.com/boringssl/316, but we won't be able
to resolve that without a consistent story for what keys are valid.
Update-Note: See above.
Bug: 316
Change-Id: Ic27df18c4f48e5e3e57a17d6fe39399e2f8d5c68
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47524
Reviewed-by: Adam Langley <agl@google.com>
It's insufficient to signal an error when the PWCT fails. We
additionally need to ensure that the invalid key material is not
returned.
Change-Id: Ic5ff719a688985a61c52540ce6d1ed279a493d27
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/44306
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Most asymmetric operations scale superlinearly, which makes them
potential DoS vectors. This (and other problems) are mitigated with
fixed sizes, like RSA-2048, P-256, or curve25519.
In older algorithms like RSA and DSA, these sizes are conventions rather
than well-defined algorithms. "Everyone" uses RSA-2048, but code which
imports an RSA key may see an arbitrary key size, possibly from an
untrusted source. This is commonly a public key, so we bound RSA key
sizes in check_modulus_and_exponent_sizes.
However, some applications import external private keys, and may need
tighter bounds. These typically parse the key then check the result.
However, parsing itself can perform superlinear work (RSA_check_key or
recovering the DSA public key).
This CL does the following:
- Rename check_modulus_and_exponent_sizes to rsa_check_public_key and
additionally call it from RSA_check_key.
- Fix a bug where RSA_check_key, on CRT-less keys, did not bound d, and
bound p and q before multiplying (quadratic).
- Our DSA verifier had stricter checks on q (160-, 224-, and 256-bit
only) than our DSA signer (multiple of 8 bits). Aligner the signer to
the verifier's checks.
- Validate DSA group sizes on parse, as well as priv_key < q, to bound
the running time.
Ideally these invariants would be checked exactly once at construction,
but our RSA and DSA implementations suffer from some OpenSSL's API
mistakes (https://crbug.com/boringssl/316), which means it is hard to
consistently enforce invariants. This CL focuses on the parser, but
later I'd like to better rationalize the freeze_private_key logic.
Performance of parsing RSA and DSA keys, gathered on my laptop.
Did 15130 RSA-2048 parse operations in 5022458us (3012.5 ops/sec)
Did 4888 RSA-4096 parse operations in 5060606us (965.9 ops/sec)
Did 354 RSA-16384 parse operations in 5043565us (70.2 ops/sec)
Did 88 RSA-32768 parse operations in 5038293us (17.5 ops/sec) [rejected by this CL]
Did 35000 DSA-1024/256 parse operations in 5030447us (6957.6 ops/sec)
Did 11316 DSA-2048/256 parse operations in 5094664us (2221.1 ops/sec)
Did 5488 DSA-3072/256 parse operations in 5096032us (1076.9 ops/sec)
Did 3172 DSA-4096/256 parse operations in 5041220us (629.2 ops/sec)
Did 840 DSA-8192/256 parse operations in 5070616us (165.7 ops/sec)
Did 285 DSA-10000/256 parse operations in 5004033us (57.0 ops/sec)
Did 74 DSA-20000/256 parse operations in 5066299us (14.6 ops/sec) [rejected by this CL]
Update-Note: Some invalid or overly large RSA and DSA keys may
previously have been accepted that are now rejected at parse time. For
public keys, this only moves the error from verification to parsing. In
some private key cases, we would previously allow signing with those
keys, but the resulting signatures would not be accepted by BoringSSL
anyway. This CL makes us behave more consistently.
Bug: oss-fuzz:24730
Change-Id: I4ad2003ee61138b693e65d3da4c6aa00bc165251
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/42504
Reviewed-by: Adam Langley <agl@google.com>
David Benjamin
Adam Langley
Shelley Vohr