271 Commits
Author SHA1 Message Date
David Benjamin 729648fb79 Rename EVP_R_EXPECTING_AN_EC_KEY_KEY to match OpenSSL
EC_KEY_KEY looks very silly. In OpenSSL, this is
EVP_R_EXPECTING_A_EC_KEY. It's a little odd that they say "a EC key"
instead of "an EC key", but ah well. (They do say "an RSA key".) May as
well match.

Update-Note: Code search finds no references to the BoringSSL name, so
this is not expected to impact anything.

Change-Id: I7563645fd269e4a62fbc46de2647f06bde00e1e4
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/81428
Auto-Submit: David Benjamin <davidben@google.com>
Commit-Queue: Lily Chen <chlily@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Lily Chen <chlily@google.com>
2025-08-18 16:36:18 -07:00
David Benjamin 76919dabe6 Move CRYPTO_refcount_t into internal headers
This removes the goofy sizeof/alignof assertion we've been making. That
was a strict aliasing violation. Now CRYPTO_refcount_t is just
CRYPTO_atomic_u32 without any fuss. It also means nothing should include
<openssl/thread.h> because it contains only deprecated symbols.

Bug: 412269080
Change-Id: Icbf98a31d5af2a4dadab3b20a410c10f98061ed7
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/79569
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
2025-05-27 13:00:52 -07:00
David Benjamin 34a1d37575 Implement functions to generate CMS external signatures
This implements just the small subset of OpenSSL's CMS API to support
the Linux kernel's sign-file.c tool. It is nowhere close to a full CMS
implementation and is not intended to become one. In particular, it does
not implement enough of CMS to support S/MIME. That requires much, much
more infrastructure than was implemented here.

CMS is, like PKCS#7, an over-engineered and cryptographically unsound
set of nestable combinators to support just about any configuration of
cryptographic operations. Profiling CMS down to a usable subset is, as a
result, more complicated, more risky, and less efficient than just
designing a bespoke structure for your use case. It is derived from
PKCS#7, and largely overlaps. However, both PKCS#7 and CMS use the v1
version number, but CMS made incompatible changes in some corner cases
that, so far, do not matter to us. (It is incompatible if you try to
layer SignedData atop another combinator, where the lack of proper
domain separation in this badly designed format is of extra risk.)

In the case of the kernel, sign-file.c wants an "external signature",
which is when the data to be signed lives elsewhere. This is, as a
result, a very, very inefficient way to concatenate an enum with a byte
string. But this is what the kernel chose, so here we are.

Because PKCS#7 and CMS are broadly the same structure, I've generalized
the internal PKCS#7 function rather than duplicating all this code. If
we ever hit the cases where PKCS#7 and CMS v1 are incompatible, plumbing
an extra boolean will be the least of our worries.

Test data was generated by compiling the actual sign-file.c against
OpenSSL and saving the output.

Change-Id: Idb0874d2b5294bfad564f3a00458c3fd044d9da5
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/78452
Auto-Submit: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2025-04-14 13:44:28 -07:00
David Benjamin 126de11fc1 Remove MSVC warning suppressions around Windows system headers
These seem to no longer be needed? Over time we have gotten a bit more
measured about enabling all of MSVC's warnings (MSVC is just not
designed to be used with -Wall), so I'm guessing that's what changed.

Change-Id: If71850136fb83841a423b63bdf65c2d546ba0223
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/77887
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
2025-03-20 21:40:35 -07:00
Bob Beck 7e529d2b39 Add Trust Anchors extension
Bug: 398275713
Change-Id: I9d15693ae88440817585b2d1d5a62244529f45b7
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/73087
Commit-Queue: Bob Beck <bbe@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
2025-03-04 12:50:43 -08:00
David Benjamin 33d1049b1f Switch the license to Apache 2.0, matching OpenSSL upstream
We use the standard Apache 2.0 file header, described in "APPENDIX: How
to apply the Apache License to your work."

This was primarily automated by running:

  git ls-tree -r --name-only HEAD | xargs go run ./util/relicense.go

See go/boringssl-relicensing-triage for the results of triaging the
output of the tool.

As part of this, switch from taking fiat-crypto under MIT license to
Apache 2.0. (It is licensed under MIT OR Apache-2.0 OR BSD-1-Clause.)

The copyright_summary tool can also be used to confirm we didn't
accidentally drop any copyright lines:

  # Run before the CL
  git grep -l Copyright | xargs go run ./util/copyright_summary.go  -out /tmp/old.json
  # Run after the CL
  git grep -l Copyright | xargs go run ./util/copyright_summary.go  -compare /tmp/old.json

Bug: 364634028
Change-Id: I17c50e761e9d077a1f92e25969e50ed35e320c59
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/75852
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2025-02-03 15:05:16 -08:00
Chris Wood 2b19cd39ba Implement SPAKE2+ and its integration in TLS 1.3
This change adds an implementation of SPAKE2+ using the P-256,
SHA256, HKDF-SHA256, and HMAC-SHA256 configuration, as specified
in RFC9383. It also integrates this algorithm into the TLS 1.3
handshake following the I-D specification available at
https://chris-wood.github.io/draft-bmw-tls-pake13/draft-bmw-tls-pake13.html

Change-Id: Ifc81ba974ddef014ea9dcbc7380ecf4db909225c
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/72427
Reviewed-by: Adam Langley <agl@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2025-01-29 13:12:39 -08:00
David Benjamin f44677cce3 Add missing error with credential/issuer matching
When we iterate over the credential list, the last credential's failure
reason becomes the overall error, so we need to add failure reasons to
the error queue.

Change-Id: If0e09c52b2d9d3d07118b66d93a2e19bc877147c
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/75747
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2025-01-27 13:27:07 -08:00
David Benjamin a9bdeed0cb Add something to the error queue when Proc-Type version is wrong
The Proc-Type header starts with a version number. From RFC 1421,
Section 4.6.1.1:

>  The "Proc-Type:" field has two subfields, separated by a comma.  The
>  first subfield is a decimal number which is used to distinguish among
>  incompatible encapsulated header field interpretations which may
>  arise as changes are made to this standard.  Messages processed
>  according to this RFC will carry the subfield value "4" to
>  distinguish them from messages processed in accordance with prior PEM
>  RFCs.

RFC 1421 was an update of RFC 1113, which used X-Proc-Type: 3,ENCRYPTED,
which we do not support. RFC 1040 defined X-Proc-Type: 2 and RFC 989
defined X-Proc-Type: 1,E. As far as I can tell, no other numbers for
Proc-Type have ever existed, and likely never will.

If we were to ever Proc-Type: 5, we currently return failure but forget
to put something on the error queue. It's possible this was originally
done for extensibility, but it just breaks internal invariants. By
returning zero, the callers will treat this as an error anyway. We'll
just confuse code that expects OpenSSL to return an error. Also
OpenSSL's PEM APIs all treat failure to decrypt (e.g. due to unsupported
future cipher) as an error, so we should treat an unsupported future PEM
encryption scheme as an error too.

Change-Id: Ia1f4f6776fea8d8a465a73105bf3ce24a587f26b
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/74809
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2025-01-08 09:27:13 -08:00
David Benjamin 4854ec106f Apply OpenSSL's "copyright consolidation" changes
This applies the OpenSSL "copyright consolidation" process from the
following upstream changes:

* https://github.com/openssl/openssl/commit/e0a651945cb5a70a2abd9902c0fd3e9759d35867
* https://github.com/openssl/openssl/commit/3fb2cf1ad19feaf6f7c571b49bd9e320eb4daf31
* https://github.com/openssl/openssl/commit/ac3d0e13777a0f0533792ed8fdd7de485675a3a2
* https://github.com/openssl/openssl/commit/c2f312f5c2379e1dcb6b3678bda27f7544508ee6
* https://github.com/openssl/openssl/commit/596d6b7e1ca5aa24700098e262cb1625f256343f
* https://github.com/openssl/openssl/commit/e18cf66aaf44b4d476625b2416386b051007d495
* https://github.com/openssl/openssl/commit/846e33c729311169d9c988ceba29484b3783f244
* https://github.com/openssl/openssl/commit/440e5d805f449d662520313b33fd90aeee86980b
* https://github.com/openssl/openssl/commit/21dcbebc6e35419f1842f39a125374ea1ba45693
* https://github.com/openssl/openssl/commit/6286757141a8c6e14d647ec733634ae0c83d9887
* https://github.com/openssl/openssl/commit/4f22f40507fea3f272637eb8e00cadf1f34b10d9
* https://github.com/openssl/openssl/commit/d2e9e320186f0917cc940f46bdf1a7e4120da9b0
* https://github.com/openssl/openssl/commit/2039c421b0e5b75ffcf6a88e39cc09089b4303dc
* https://github.com/openssl/openssl/commit/b1322259d93cf6b6286f9febcd468b6a9f577d91
* https://github.com/openssl/openssl/commit/aa6bb1352b1026b20a23b49da4efdcf171926eb0
* https://github.com/openssl/openssl/commit/b6cff313cbb1d0381b329fe4f6a8f009cdb270e4
* https://github.com/openssl/openssl/commit/9e20068958b8c1772067299dda7df0b8a82283b4
* https://github.com/openssl/openssl/commit/6aa36e8e5a062e31543e7796f0351ff9628832ce
* https://github.com/openssl/openssl/commit/44c8a5e2b9af8909844cc002c53049311634b314

This was mostly automated, but partially manual. The automated portion
can be reproduced by checking OpenSSL to commit
44c8a5e2b9af8909844cc002c53049311634b314, and running the following:

  git grep -l -E 'Copyright remains Eric Young|Copyright.*The OpenSSL Project\.|Written by.*for the OpenSSL Project' crypto/ decrepit/ include/ ssl/ | grep -v objects.go > files.txt
  cat files.txt | xargs -n1 perl -i ./util/copyright.pl

From there, some years were fixed up manually according to
go/openssl-copyright-consolidation-comparison (internal-only).

Three files required additional manual fixing:

- crypto/ecdh_extra/ecdh_extra.cc
- crypto/fipsmodule/ecdh/ecdh.cc.inc
- include/openssl/ecdh.h

These files have an OpenSSL header, but *after* a different header, so
the script does not correctly detect the now redundant OpenSSL header.
They were manually modified to remove it. This matches what seems to
have been done to crypto/ec/ecdh_ossl.c in OpenSSL's
4f22f40507fea3f272637eb8e00cadf1f34b10d9.

Bug: 364634028
Change-Id: I79a559a409ebe2476f2cb8a48a488ac5dd77c90a
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/74710
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2025-01-03 13:56:35 -08:00
Adam Langley 59fc518963 Put structs in anonymous namespaces to avoid ODR worries.
The referenced bug notes some ODR warnings in an unspecified
configuration. (Which I can't get AppleClang or GCC 14 to reproduce, at
least.) This is likely due to us switching to C++. The ODR rules in C++
are a little different, but also perhaps the detection is only kicking
in for C++.

Either way, structs in .cc files are generally not intended to leave
that compilation unit. (Unless it's an opaque struct listed in base.h.)
There's no such thing as `static struct` so this change wraps many
structs in .cc files in `namespace {`. There are also lots of structs in
test file. Those are less concerning, but test files should mostly
entirely be in a namespace so this change does that where possible for
test files containing structs.

Bug: 384186552
Change-Id: I6ccf715fbcdc3ea6260b5d5d05f305182b1a9450
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/74407
Auto-Submit: Adam Langley <agl@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2024-12-16 16:47:03 -08:00
David Benjamin 6f4159567d Start maintaining an AUTHORS file
Following the guidance in
https://opensource.google/documentation/reference/releasing/authors,
start maintaining an AUTHORS file.

Update all existing Google copyright lines to 'The BoringSSL Authors'
per the document. This CL also changes the styling to match the new
guidance: removed the '(c)' and the comma.

All other existing copyright lines are left unmodified. Going forward,
our preference will be that new contributions to BoringSSL use 'The
BoringSSL Authors', optionally adding to the AUTHORS file if the
contributor desires.

To avoid being presumptuous, this CL does *not* proactively list every
past contributor in the BoringSSL half of the AUTHORS file. Past
contributors are welcome to send us a patch to be added, or request that
we add you. (Listed or not, the commit log continues to be a more
accurate record, and any existing non-Google copyright lines were left
unmodified.)

The OpenSSL half of the AUTHORS file is seeded with the contents of the
current OpenSSL AUTHORS file, as of writing. The current contents in the
latest revision of the 1.1.1 branch
(b372b1f76450acdfed1e2301a39810146e28b02c) and master
(d992e8729ee38b082482dc010e090bb20d1c7bd5) are identical, just formatted
in text vs Markdown.

Note when reviewing: CONTRIBUTING.md and AUTHORS contain non-mechanical
changes.

Bug: 364634028
Change-Id: I319d0ee63ec021ad85e248e8e3304b9cf9566681
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/74149
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2024-12-11 13:52:41 -08:00
David Benjamin c1ecbd11c7 Remove extra va_end in err_add_error_vdata
We should va_end(args_copy), but the function should not va_end(args).
The caller is responsible for that one.

As I understand it, this in benign: in every target we care about,
va_end is a no-op.

Bug: 379096238
Change-Id: I063c775ecd496edc1b5c69c027d1dd9a04f578d1
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/74088
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
2024-12-09 19:57:51 +00:00
Adam Langley 5813c2c10c crypto: switch to C++
This change switches nearly all of BoringSSL to use C++. The public
functions still use the C ABI, and so code written in C can still use
BoringSSL. Also the use of the C++ standard library is minimal and no
run-time requirement for it is intended.

Change-Id: I902d2f51a3c8d6bd0dc4aabe1b192a15d7b788e8
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/72747
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
2024-11-26 21:10:44 +00:00
David Benjamin 7a6022067f Remove the old SSL_R_APPLICATION_DATA_INSTEAD_OF_HANDSHAKE logic
Back when we were deploying TLS 1.3, we were tracking how often some
buggy middlebox interfered with the new TLS version and prevented sites
from upgrading.

One middlebox's failure mode was that they dropped ServerHello and
passed the remaining records through. This error code was caught by
Chromium to histogram. TLS 1.3 has long since been deployed, and we've
dropped that histogramming code, so remove this special case.

See https://crbug.com/41325349 for some of the history here.

Change-Id: I70c1ada1ed3d9ba73dfe75213a0233e407599c98
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/73548
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
2024-11-26 20:31:56 +00:00
David Benjamin 89f097740e Avoid strdup in crypto/err/err.c
This makes me sad, but strdup may be more trouble than is worth it?
Being not in C (until C23) and only a (by POSIX standards) recent
addition to POSIX means a lot of folks seem to make it unnecessarily
hard to use:

- MSVC adds a deprecation warning that we have to suppress

- glibc gates it on feature macros; we just don't notice because we
  already have to work around their bad behavior for pthread_rwlock

- musl gates it on feature macros, which was one of the things that
  tripped cl/583161936

Given we only want to use strdup in one file (err.c, which wants to
avoid OPENSSL_malloc), a small reimplementation is probably not the end
of the world.

While I'm here, we can actually make OPENSSL_strdup's implementation a
little simpler.

Change-Id: I4e6c743b3104a67357d7d527c178c615de6bc844
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/64047
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2024-04-10 19:56:26 +00:00
David Benjamin fe0c91e744 Check in pre-generated perlasm and error data files
This adds a tool for managing pre-generated files, aligning our CMake
and non-CMake builds. The plan is roughly:

The source of truth for the file lists will (eventually) be build.json.
This describes the build in terms of the files that we directly edit.

However, we have a two-phase build. First a pregeneration step
transforms some of the less convenient inputs into checked in files.
Notably perlasm files get expanded. This produces an equivalent JSON
structure with fewer inputs. The same tool then outputs that structure
into whatever build systems we want.

This initial version pre-generates err_data.c and perlasm files. I've
not wired up the various build formats, except for CMake (for the CMake
build to consume) and JSON (for generate_build_files.py to parse).
build.json is also, for now, only a subset of the build. Later changes

The upshot of all this is we no longer have a Perl build dependency!
Perl is now only needed when working on BoringSSL. It nearly removes the
Go one, but Go is still needed to run and (for now) build the tests.

To keep the generated files up-to-date, once this lands, I'll update our
CI to run `go run ./util/pregenerate -check` which asserts that all
generated files are correct. From there we can land the later changes in
this patch series that uses this more extensively. My eventual goal is
to replace generate_build_files.py altogether and the
"master-with-bazel" branch. Instead we'll just have sources.bzl,
sources.gni, etc. all checked into the tree directly. And then the
normal branch will just have both a CMake and Bazel build in it.

Update-Note: generate_build_files.py no longer generates assembly files
or err_data.c. Those are now checked into the tree directly.

Bug: 542
Change-Id: I71f5ff7417be811f8b7888b345279474e6b38ee9
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/67288
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2024-03-22 05:15:56 +00:00
David Benjamin e57ab142c0 Add some barebones support for DH in EVP
OpenSSH needs this. Features that have been intentionally omitted for
now:

- X9.42-style Diffie-Hellman ("DHX"). We continue not to support this.
  Use ECDH or X25519 instead.

- SPKI and PKCS#8 serialization. Use ECDH or X25519 instead. The format
  is a bit ill-defined. Moreover, until we solve the serialization
  aspects of https://crbug.com/boringssl/497, adding them would put this
  legacy algorithm on path for every caller.

- Most of the random options like stapling a KDF, etc. Though I did add
  EVP_PKEY_CTX_set_dh_pad because it's the only way to undo OpenSSL's
  bug where they chop off leading zeros by default.

- Parameter generation. Diffie-Hellman parameters should not be
  generated at runtime.

This means you need to bootstrap with a DH object and then wrap it in an
EVP_PKEY. This matches the limitations of the EVP API in OpenSSL 1.1.x.
Unfortunately the OpenSSL 3.x APIs are unsuitable for many, many
reasons, so I expect when we get further along in
https://crbug.com/boringssl/535, we'll have established some patterns
here that we can apply to EVP_PKEY_DH too.

Change-Id: I34b4e8799afb266ea5602a70115cc2146f19c6a7
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/67207
Reviewed-by: Theo Buehler <theorbuehler@gmail.com>
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
2024-03-21 03:34:31 +00:00
David Benjamin dbad745811 Add ERR_lib_symbol_name and ERR_reason_symbol_name
CPython needs this operation. See
https://github.com/openssl/openssl/issues/19848 and
https://discuss.python.org/t/error-tables-in-the-ssl-module/25431 for
details.

In principle, our functions already return the symbol names. The
differences are:

- Our library strings say "common libcrypto routines" instead of
  "CRYPTO".
- The global reason codes say "internal error" instead of
  "INTERNAL_ERROR". (We should consider changing this.)
- The library forwarding reason codes (ERR_R_BN_LIB) say the library
  string instead of "BN_LIB". (We should consider changing this.)
- errnos report strerror
- Unknown errors return "unknown error" because we've found that
  projects tend to crash when these APIs return NULL.

The new APIs consistently return the symbol name, when available. If
unavailable (ERR_LIB_SYS's errno reasons), it returns NULL because I
assume callers would rather be able to handle that case themselves.
Hopefully this will not be as common so callers can take on this one.

Change-Id: Idd9e4b1cb5a4f64513310d8066d6bf3970722c23
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/66807
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2024-03-11 23:26:13 +00:00
Victor Tan 3309ca6638 Add ALPS codepoint supports for split handshake
This change adds ALPS codepoint supports on split handshake.
serialize_features sends list of codepoints, handshaker will serialize
the codepoint when calling SSL_serialize_handback, and send the chosen
codepoint to the server, server can apply the codepoint when
SSL_apply_handback.

Change-Id: Id7bc985c4b9847b7c337595f1bc23b2af93d96e7
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/63265
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2023-10-26 19:35:18 +00:00
David Benjamin d85444e741 Consistently reject large p and large q in DH
When applications use Diffie-Hellman incorrectly, and use
attacker-supplied domain parameters, rather than known-valid ones (as
required by SP 800-56A, 5.5.2), algorithms that aren't designed with
attacker-supplied parameters in mind become attack surfaces.

CVE-2023-3446 and CVE-2023-3817 in OpenSSL cover problems with the
DH_check function given large p and large q. This CL adds some fast
validity checks to the DH parameters before running any operation. This
differs from upstream in a few ways:

- Upstream only addressed issues with DH_check. We also check in
  DH_generate_key and DH_check_pub_key.

- For a more consistent invariant, reuse the existing DH modulus limit.
  Ideally we'd enforce these invariants on DH creation, but this is not
  possible due to OpenSSL's API. We additionally check some other
  cheap invariants.

This does not impact TLS, or any applications that used Diffie-Hellman
correctly, with trusted, well-known domain parameters.

Ultimately, that this comes up at all is a flaw in how DH was specified.
This is analogous to the issues with ECC with arbitrary groups and DSA,
which led to https://github.com/openssl/openssl/issues/20268
CVE-2022-0778, CVE-2020-0601, and likely others. Cryptographic
primitives should be limited to a small set of named, well-known domain
parameters.

Update-Note: Egregiously large or invalid DH p, q, or g values will be
more consistently rejected in DH operations. This does not impact TLS.
Applications should switch to modern primitives such as X25519 or ECDH
with P-256.

Change-Id: I666fe0b9f8b71632f6cf8064c8ea0251e5c286bb
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/62226
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2023-08-14 20:54:13 +00:00
David Benjamin 6bd1e15046 Silence -Wformat-truncation warning in crypto/err/err.c
This warning was being tripped because lib_buf and reason_buf made GCC,
incorrectly, believe that the strings could get that long, and then
attempted to sum up the snprintf to 120, obtained by inlining some
things.

Those buffers were larger than they needed to be, so bringing it down is
sufficient to silence things. That said, the buffer bounds are supplied
by the caller and it is expected that truncation can occur, so the
warning is just incorrect. The warning can also be silenced by checking
the snprintf return value. As we're already trying to detect truncation,
we may as well do it with the return value and skip the extra strlen
call.

Either of the two changes is sufficient to suppress the warning, but
both seem worthwhile, so I've done them both.

Change-Id: Ia1b1de67bba55da6f0d07e3682165a1820ce2c9e
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/61805
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
2023-07-19 18:47:48 +00:00
David Benjamin 23d6e4cce9 Replace BIO_snprintf with snprintf within the library
Our BIO_snprintf is just a thin wrapper over the libc one, and we
already call it directly in other places. Just call the libc one
consistently.

Change-Id: Ia7daf26b9789ddcecab67118c4ec4a077aad5a22
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/61685
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
2023-07-16 19:42:57 +00:00
David Benjamin 70be01270b Use constant curve-specific groups whenever possible
Also remove unnecessary EC_GROUP_free calls. EC_GROUP_free is only
necessary in codepaths where arbitrary groups are possible.

Bug: 20
Change-Id: I3dfb7f07b890ab002ba8a302724d8bc671590cfe
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/60932
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2023-07-11 20:07:57 +00:00
David Benjamin 0f222e69b1 Clear some size_t truncations
Also fix the comments for ERR_STATE because they were actually wrong.

Bug: 516
Change-Id: I3b352fc75e63075a9f02f33c6e23da0f821a323e
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/61425
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
2023-07-10 20:21:22 +00:00
David Benjamin 04c3d40f06 Remove CRYPTO_MUTEX from public headers
We no longer need to define CRYPTO_MUTEX in public headers. This
simplifies a pile of things. First, we can now use pthread_rwlock_t
without any fuss, rather than trying to guess the size on glibc.

As a result, CRYPTO_MUTEX and CRYPTO_STATIC_MUTEX can be merged into one
type. We can almost do this to CRYPTO_refcount_t too. BIO is the one
straggler remaining.

Fixed: 325
Change-Id: Ie93c9f553c0f02ce594b959c041b00fc15ba51d2
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/60611
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
2023-06-09 14:13:40 +00:00
David Benjamin 825bec8c88 Remove variable expansion from CONF fuzzer
CONF supports a variable expansion feature, which allows a config file
to easily grow exponentially.

2d05568a7b (upstream's
6a6213556a80ab0a9eb926a1d6023b8bf44f2afd) capped the expansion to 65536
bytes, but this still allows a small input to produce a fairly large
output. (Once we have one large value, it only takes five characters
make a new key that references it, which is an expansion factor of
around 13,000.) This, combined with the string-based extensions
machinery's many quadratic behaviors (see
b92fcfdc17), means fuzzers hit timeouts.

We have very few uses of these APIs left, and none of them use this
feature. Just remove it. While none of these super-linear behaviors are
DoS bugs per se (they should never be passed untrusted input), there's
no sense in carrying an unused feature that only frustrates the fuzzers.

Update-Note: NCONF_load and NCONF_load_bio no longer support the $foo
variable expansion syntax. If you are using these functions in your
project, remove them.

Bug: oss-fuzz:59049
Change-Id: I85832ae1d05373ee420f4fb68197786736ca8272
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/60105
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2023-05-24 17:25:03 +00:00
David Benjamin ece1f86968 Re-add go:build ignore lines
This reverts commit bab2f96e26. This
clears the sea of red in my editor.

Change-Id: I600ef6c36556fb526da729f0f0d8bc69db5c5a08
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/59186
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2023-04-25 18:50:59 +00:00
David Benjamin bcecc7d834 Replace sort.Sort with sort.Slice
Change-Id: I6e0361a42b9612ba4294cc8806203ea445bc9257
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/58945
Reviewed-by: Bob Beck <bbe@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
2023-04-19 23:55:21 +00:00
David Benjamin 474ddf8ba9 Cap the number of ECDSA and DSA sign iterations.
When the parameters are incorrect, all assumptions of (EC)DSA fly out
the window, including whether the retry loop actually terminates.

While ECDSA is broadly used with fixed, named groups, DSA was
catastrophically mis-specified with arbitrary parameters being the
default and only mode. Cap the number of retries in DSA_do_sign so
invalid DSA groups cannot infinite loop, e.g. if the "generator" is
really nilpotent.

This also caps the iteration count for ECDSA. We do, sadly, support
arbitrary curves via EC_GROUP_new_curve_GFp, to help Conscrypt remain
compatible with a badly-designed Java API. After
https://boringssl-review.googlesource.com/c/boringssl/+/51925, we
documented that untrusted parameters are not supported and may produce
garbage outputs, but we did not document that infinite loops are
possible. I don't have an example where an invalid curve breaks ECDSA,
but as it breaks all preconditions, I cannot be confident it doesn't
exist, so just cap the iterations.

Thanks to Hanno Böck who originally reported an infinite loop on
invalid DSA groups. While that variation did not affect BoringSSL, it
inspired us to find other invalid groups which did.

Thanks also to Guido Vranken who found, in
https://github.com/openssl/openssl/issues/20268, an infinite loop when
the private key is zero. That was fixed in the preceding CL, as it
impacts valid groups too, but the infinite loop is ultimately in the
same place, so this change also would have mitigated the loop.

Update-Note: If signing starts failing with ECDSA_R_INVALID_ITERATIONS,
something went horribly wrong because it should not be possible with
real curves. (Needing even one retry has probability 2^-256 or so.)

Change-Id: If8fb0157055d3d8cb180fe4f27ea7eb349ec2738
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/57228
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2023-02-23 15:59:47 +00:00
David Benjamin bab2f96e26 Revert go:build ignore lines
This convention seems to break with some other tooling we have. Until we
figure out how to resolve that, remove the lines.

This partially reverts 54b04fdc21 but
keeps the fixes to the license header comments.

Change-Id: I4f08a9f3daf65d17b4c78ac6f4ac3de234ec3436
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/57366
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
2023-02-16 23:06:41 +00:00
Bob Beck fc524c161e Make ERR and thread use system malloc.
This will let us call ERR and thread_local from OPENSSL_malloc
without creating a circular dependency. We also make
ERR_get_error_line_data add ERR_FLAG_MALLOCED to the returned
flags value, since some projects appear to be making
assumptions about it being there.

Bug: 564

Update-Note: Any recent documentation (in all OpenSSL forks) for the ERR functions
cautions against freeing the returned ERR "data" strings, as freeing them is handled
by the error library. This change can make an existing double free bug more
obvious by being more likely to cause a crash with the double free.

Change-Id: Ie30bd3aee0b506473988b90675c48510969db31a
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/57045
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
Auto-Submit: Bob Beck <bbe@google.com>
2023-02-11 17:32:19 +00:00
David Benjamin 54b04fdc21 Mark standalone Go scripts with go:build ignore
gopls currently litters our project with a sea of red, because it
assumes Go files are part of a package, but we have a lot of standalone
Go scripts. (If there are C files in the same directory as the script,
it gets upset about cgo. If there are multiple standalone scripts in the
same directory, it gets uspet about duplicate files.)

Per https://github.com/golang/go/issues/49657 and
https://github.com/golang/tools/blob/master/gopls/doc/settings.md#standalonetags-string,
the convention seems to be a go:build ignore tag. Newer versions of
gopls run in a "standalone" mode, so we still get all the nice LSP
features.

As part of this, I had to align the license header comments from /*
block comments */ to // line comments. Go build constraints can only be
preceded by blank lines and line comments. Block comments apparently
aren't allowed. (See https://pkg.go.dev/cmd/go#hdr-Build_constraints.)
If I leave the file unconverted, go fmt will immediately move the
comment to above the license block.

Change-Id: I47c69255522e9aae2bdb97a6e83fcc6ce0cf29d5
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/56525
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
2023-01-31 19:09:38 +00:00
David Benjamin 029d0e77fb Rewrite X.509 policy tree logic.
This reimplements policy handling using a similar DAG structure as in
https://chromium-review.googlesource.com/c/chromium/src/+/4111415. The
main difference is that, being C, we don't have std::set or std::map
easily available. But the algorithm can be implemented purely with
sorted lists, while remaining subquadratic.

This implementation relies on two assumptions:

1. We do not return the policy tree. This was removed in
   https://boringssl-review.googlesource.com/c/boringssl/+/53327

2. We do not return the final set of certificate policies. I.e.,
   certificate policy checking is only used for evaluating policy
   constraints and X509_V_FLAG_EXPLICIT_POLICY.

The second assumption is not very important. It mostly simplifies
has_explicit_policy slightly.

In addition, this new implementation removes the per-certificate policy
cache. Instead, we just process the policy extensions anew on
certificate verification. This avoids a mess of threading complexity,
including a race condition in the old logic. See
https://boringssl-review.googlesource.com/c/boringssl/+/55762 for a
description of the race condition.

Change-Id: Ifba9037588ecff5eb6ed3c34c8bd7611f60013a6
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/56036
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
2023-01-19 23:01:04 +00:00
David Benjamin b7d6320be9 Replace OPENSSL_STATIC_ASSERT with static_assert.
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>
2022-07-30 20:16:43 +00:00
Alex Gaynor 225e8d39b5 Use X509 certificate alias as friendlyName in PKCS12
Bug: 481
Change-Id: I5c1dd6e39874cd1e88cb6fd0b3a6c6c6fac0db85
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/51665
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2022-03-28 17:57:41 +00:00
David Benjamin bdc35b6361 Rewrite and tighten ASN1_INTEGER encoding and decoding.
This fixes several issues around ASN1_INTEGER handling. First, invalid
INTEGERs (not allowed in BER or DER) will no longer be accepted by
d2i_ASN1_INTEGER. This aligns with upstream OpenSSL, which became strict
in 6c5b6cb035666d46495ccbe4a4f3d5e3a659cd40, part of OpenSSL 1.1.0.

In addition to matching the standard, this is needed to avoid
round-tripping issues: ASN1_INTEGER uses a sign-and-magnitude
representation, different from the DER two's complement representation.
That means we cannot represent invalid DER INTEGERs. Attempting to do so
messes up some invariants and causes values to not round-trip correctly
when re-encoded. Thanks to Tavis Ormandy for catching this.

Next, this CL tidies the story around invalid ASN1_INTEGERs (non-minimal
and negative zero). Although we will never produce them in parsing, it
is still possible to manually construct them with ASN1_STRING APIs.
Historically (CVE-2016-2108), it was possible to get them out of the
parser, due to a different bug, *and* i2d_ASN1_INTEGER had a memory
error in doing so. That different bug has since been fixed, but we
should still handle them correctly and test this. (To that end, this CL
adds a test we ought to have added importing upstream's
3661bb4e7934668bd99ca777ea8b30eedfafa871 back in
c4eec0c16b02c97a62a95b6a08656c3a9ddb6baa.)

As the two's complement invariants are subtle as it is, I've opted to
just fix the invalid values before encoding. However, invalid
ASN1_INTEGERs still do not quite work right because ASN1_INTEGER_get,
ASN1_INTEGER_cmp, and ASN1_STRING_cmp will all return surprising values
with them. I've left those alone.

Finally, that leads to the zero value. Almost every function believes
the representation of 0 is a "\0" rather than "". However, a
default-constructed INTEGER, like any other string type, is "". Those do
not compare as equal. crypto/asn1 treats ASN1_INTEGER generically as
ASN1_STRING enough that I think changing the other functions to match is
cleaner than changing default-constructed ASN1_INTEGERs. Thus this CL
removes all the special cases around zero.

Update-Note: Invalid INTEGERs will no longer parse, but they already
would not have parsed in OpenSSL. Additionally, zero is now internally
represented as "" rather than "\0".

Bug: 354
Change-Id: Id4d51a18f32afe90fd4df7455b21e0c8bdbc5389
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/51632
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2022-03-08 17:28:24 +00:00
David Benjamin 366e886628 Deduplicate the rest of ASN1_INTEGER and ASN1_ENUMERATED.
These functions need some work, but first avoid the duplicate versions.
See also upstream's 6c5b6cb035666d46495ccbe4a4f3d5e3a659cd40.

Update-Note: ASN1_INTEGER_to_BN and ASN1_ENUMERATED_to_BN will now fail
when called on an ASN1_STRING/ASN1_INTEGER/ASN1_ENUMERATED (they're all
the same type) with the wrong runtime type value. Previously, callers
that mixed them up would get the right answer on positive values and
silently misinterpret the input on negative values. This change matches
OpenSSL's 1.1.0's behavior.

Change-Id: Ie01366003f7b2e49477cb73eaf7eaac26d86675d
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/51631
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2022-03-08 16:13:34 +00:00
David Benjamin 7198d1132b Explicitly reject self-referential ech_outer_extensions.
The ECH extension is not covered in the AAD and so should not be
referenced in ech_outer_extensions. We end up rejecting this anyway when
checking for valid ClientHelloInners, but better to reject this
explicitly, as the spec suggests.

As part of this, use the more specific error in the various tests, so we
can distinguish the two cases. (DECODE_ERROR is coming from an extra,
probably unnecessary, error in ssl_decode_client_hello_inner's caller.)

Bug: 275
Change-Id: Ibeff55e5e1b7646ce9c68c5847cd1b40a47e6480
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/51185
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2022-01-28 19:47:43 +00:00
Adam Langley f797570320 Ignore duplicates in |X509_STORE_add_*|
This change imports upstream's
https://github.com/openssl/openssl/commit/c0452248ea1a59a41023a4765ef7d9825e80a62b

Change-Id: Ib50ff9eb8c48d9580aa2ffcae92d3990cc987e30
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/50905
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2022-01-13 17:31:46 +00:00
David Benjamin 731d6cbef9 Add ERR_set_error_data for compatibility.
rust-openssl, rather than using Rust's existing error types, exposes the
OpenSSL error queue as the error type in its public callback types.
Supporting a simplified version of ERR_set_error_data is simple enough,
so it's easiest just to add this function.

Unlike OpenSSL's, we don't attempt to support non-string error data. We
also don't try to retain borrowed pointers. If the caller did not pass
ownership, make a copy internally.

Change-Id: I909eebc2867ab1f3b9975546a106ee1f762bf516
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/50625
Reviewed-by: Adam Langley <agl@google.com>
2021-11-30 22:04:19 +00:00
David Benjamin 13c67c99d8 Enforce DER rules for BIT STRING values.
DER requires BIT STRING padding bits be zero.

Bug: 354
Change-Id: Id59154cc4e77f91df8b9ff1eb1b09514116808da
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/50288
Reviewed-by: Adam Langley <agl@google.com>
2021-11-01 18:08:46 +00:00
David Benjamin 491af10360 Check for trailing data in extensions.
X509V3_EXT_d2i should notice if an extension has extra data at the end.

Update-Note: Some previously accepted invalid certicates may be
rejected, either in certificate verification or in X509_get_ext_d2i.

Bug: 352
Change-Id: Iacbb74a52d15bf3318b4cb8271d44b0f0a2df137
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/50285
Reviewed-by: Adam Langley <agl@google.com>
2021-11-01 17:09:21 +00:00
David Benjamin 18b6836b2f Update to draft-ietf-tls-esni-13.
Later CLs will clean up the ClientHello construction a bit (draft-12
avoids computing ClientHelloOuter twice). I suspect the transcript
handling on the client can also be simpler, but I'll see what's
convenient after I've changed how ClientHelloOuter is constructed.

Changes of note between draft-10 and draft-13:

- There is now an ECH confirmation signal in both HRR and SH. We don't
  actually make much use of this in our client right now, but it
  resolves a bunch of weird issues around HRR, including edge cases if
  HRR applies to one ClientHello but not the other.

- The confirmation signal no longer depends on key_share and PSK, so we
  don't have to work around a weird ordering issue.

- ech_is_inner is now folded into the main encrypted_client_hello code
  point. This works better with some stuff around HRR.

- Padding is moved from the padding extension, computed with
  ClientHelloInner, to something we fill in afterwards. This makes it
  easier to pad up the whole thing to a multiple of 32. I've accordingly
  updated to the latest recommended padding construction, and updated
  the GREASE logic to match.

- ech_outer_extensions is much easier to process because the order is
  required to be consistent. We were doing that anyway, and now a simple
  linear scan works.

- ClientHelloOuterAAD now uses an all zero placeholder payload of the
  same length. This lets us simplify the server code, but, for now, I've
  kept the client code the same. I'll follow this up with a CL to avoid
  computing ClientHelloOuter twice.

- ClientHelloOuterAAD is allowed to contain a placeholder PSK. I haven't
  filled that in and will do it in a follow-up CL.

Bug: 275
Change-Id: I7464345125c53968b2fe692f9268e392120fc2eb
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48912
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2021-09-01 22:12:30 +00:00
David Benjamin 2d10c18b3a Fix i2v_GENERAL_NAME to not assume NUL terminated strings
See also 174ba8048a7f2f5e1fca31cfb93b1730d9db8300 from upstream. This
differs from the upstream CL in that:

- We don't silently drop trailing NULs.

- As a NUL-terminated C string, the empty string is a non-NULL pointer
  to an array containing a zero byte. Use the latter consistently.

Change-Id: I99c6c4c26be5a1771c56c6ab356425f1b85be41d
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/49006
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2021-08-24 22:30:37 +00:00
David Benjamin ba423c9a1b Implement ClientHelloOuter handshakes.
If a client offers ECH, but the server rejects it, the client completes
the handshake with ClientHelloOuter in order to authenticate retry keys.
Implement this flow. This is largely allowing the existing handshake to
proceed, but with some changes:

- Certificate verification uses the other name. This CL routes this up to
  the built-in verifier and adds SSL_get0_ech_name_override for the
  callback.

- We need to disable False Start to pick up server Finished in TLS 1.2.

- Client certificates, notably in TLS 1.3 where they're encrypted,
  should only be revealed to the true server. Fortunately, not sending
  client certs is always an option, so do that.

  Channel ID has a similar issue. I've just omitted the extension in
  ClientHelloOuter because it's deprecated and is unlikely to be used
  with ECH at this point. ALPS may be worth some pondering but, the way
  it's currently used, is not sensitive.

  (Possibly we should change the draft to terminate the handshake before
  even sending that flight...)

- The session is never offered in ClientHelloOuter, but our internal
  book-keeping doesn't quite notice.

I had to replace ech_accept with a tri-state ech_status to correctly
handle an edge case in SSL_get0_ech_name_override: when ECH + 0-RTT +
reverify_on_resume are all enabled, the first certificate verification
is for the 0-RTT session and should be against the true name, yet we
have selected_ech_config && !ech_accept. A tri-state tracks when ECH is
actually rejected. I've maintained this on the server as well, though
the server never actually cares.

Bug: 275
Change-Id: Ie55966ca3dc4ffcc8c381479f0fe9bcacd34d0f8
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48135
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2021-06-24 18:07:19 +00:00
David Benjamin 83a49939ab Add most of an ECH client implementation.
Based on an initial implementation by Dan McArdle at
https://boringssl-review.googlesource.com/c/boringssl/+/46784

This CL contains most of a client implementation for
draft-ietf-tls-esni-10. The pieces missing so far, which will be done in
follow-up CLs are:

1. While the ClientHelloInner is padded, the server Certificate message
   is not. I'll add that once we resolve the spec discussions on how to
   do that. (We were originally going to use TLS record-level padding,
   but that doesn't work well with QUIC.)

2. The client should check the public name is a valid DNS name before
   copying it into ClientHelloOuter.server_name.

3. The ClientHelloOuter handshake flow is not yet implemented. This CL
   can detect when the server selects ClientHelloOuter, but for now the
   handshake immediately fails. A follow-up CL will remove that logic
   and instead add the APIs and extra checks needed.

Otherwise, this should be complete, including padding and compression.

The main interesting point design-wise is that we run through
ClientHello construction multiple times. We need to construct
ClientHelloInner and ClientHelloOuter. Then each of those has slight
variants: EncodedClientHelloInner is the compressed form, and
ClientHelloOuterAAD just has the ECH extension erased to avoid a
circular dependency.

I've computed ClientHelloInner and EncodedClientHelloInner concurrently
because the compression scheme requires shifting the extensions around
to be contiguous. However, I've computed ClientHelloOuterAAD and
ClientHelloOuter by running through the logic twice. This probably can
be done better, but the next draft revises the construction anyway, so
I'm thinking I'll rework it then. (In the next draft, we use a
placeholder payload of the same length, so we can construct the
ClientHello once and fill in the payload.)

Additionally, now that we have a client available in ssl_test, this adds
a threading test to confirm that SSL_CTX_set1_ech_keys is properly
synchronized. (Confirmed that, if I drop the lock in
SSL_CTX_set1_ech_keys, TSan notices.)

Change-Id: Icaff68b595035bdcc73c468ff638e67c84239ef4
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48004
Reviewed-by: Adam Langley <agl@google.com>
2021-06-11 18:36:38 +00:00
David Benjamin 24545c541c Add a basic API to make ECHConfigs.
We'll probably need to make this more complex later, but this should be
a start. I had hoped this would also simplify tests, MakeECHConfig() was
still needed to generate weird inputs for tests. I've instead tidied
that up a bit with a params structure. Now the only hard-coded ECHConfig
in tests is to check the output of the new API.

Bug: 275
Change-Id: I640a224fb4b7a7d20e8a2cd7a1e75d1e3fe69936
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48003
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2021-06-11 18:33:36 +00:00
David Benjamin 3a036c76eb Add SSL_ech_accepted API and ech_is_required alerts.
The first thing any deployment will want to monitor is whether ECH was
actually used. Also it's useful if the command-line tool can output
this. (The alert is how the client signals it discarded the connection
due to ECH reject.)

This also disables ECH with the handoff mechanism for now. (The
immediate cause being that ech_accept isn't serialized.) We'll probably
need to make some decisions around the ordering here, since ECH affects
where the true ClientHello is available.

Bug: 275
Change-Id: Ie4559733290e653a514fcd94431090bf86bc3172
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47911
Reviewed-by: Adam Langley <agl@google.com>
2021-06-03 21:02:25 +00:00
David Benjamin eec7f32470 Use a placeholder for unknown errors in ERR_*_error_string.
Change-Id: I3a16fa731cfa7c92e5fec19f78ae48650921f626
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47104
Reviewed-by: Adam Langley <agl@google.com>
2021-04-22 16:19:22 +00:00