These functions aid in meeting specific compliance goals and allows
configuration of things like TLS 1.3 cipher suites, which are otherwise
not configurable.
Change-Id: I668afc734a19ecd4b996eaa23be73ce259b13fa2
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/52625
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
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>
std::initializer_list appears to work by instantiating a T[N] at the
call site (which is what we were doing anyway), so I don't believe there
is a runtime dependency.
This also adds a way for individual entries to turn themselves off,
which means we don't need to manually check for some unsolicited
extensions.
Change-Id: I40f79b6a0e9c005fc621f4a798fe201bfbf08411
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48910
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
We do this enough that it's worth extracting a common parser. And this
gives a struct we can pass around. Note this moves the server extensions
block parsing out of ssl_scan_serverhello_tlsext.
I've also consolidated a few error conditions to tighten the code up a
bit: the TLS 1.2 code distinguishes unknown from unadvertised cipher,
while the TLS 1.3 code didn't. And seeing the wrong legacy version
number in TLS 1.3 is really just a syntax error since it's not the
version field anymore. (RFC8446 specifies the value.)
Change-Id: Ia2f44ff9a3899b5a594569f1b258f2b487930496
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48908
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
The cipher suite, like the version, is determined by the first server
message, independent of whether it's ServerHello or HelloRetryRequest.
We can simplify this by just processing it before we branch on which it
was.
Change-Id: I747f515e9e5b05a42cbed6e7844808d0fc79a30b
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48906
Reviewed-by: Adam Langley <agl@google.com>
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>
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>
Like the early_data CL, this does shift a bit of logic that was
previously hidden away in the callbacks. For key_share, this is probably
a good move independent of ECH. The logic around HRR, etc., was a little
messy.
Bug: 275
Change-Id: Iafbcebdf66ce1f7957d798a98ee6b996fff24639
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47986
Reviewed-by: Adam Langley <agl@google.com>
Also add ECH GREASE state into the mix. Clearing this isn't critical,
especially now that we have an SSL_HANDSHAKE structure, but it's easy
enough.
Bug: 275
Change-Id: If1aa8d5c0c8fdb5af710852778ce452c507a2524
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47985
Reviewed-by: Adam Langley <agl@google.com>
The remaining remnants of Channel ID all configure the private key ahead
of time. Unwind the callback machinery, which cuts down on async points
and the cases we need to test.
This also unwinds some odd interaction between the callback and
SSL_set_tls_channel_id_enabled: If a client uses
SSL_set_tls_channel_id_enabled but doesn't set a callback, the handshake
would still pause at SSL_ERROR_WANT_CHANNEL_ID_LOOKUP. This is now
removed, so SSL_set_tls_channel_id_enabled only affects the server and
SSL_CTX_set1_tls_channel_id only affects the client.
Update-Note: SSL_CTX_set_channel_id_cb is removed.
SSL_set_tls_channel_id_enabled no longer enables Channel ID as a client,
only as a server.
Change-Id: I89ded99ca65e1c61b1bc4e009ca0bdca0b807359
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47907
Reviewed-by: Adam Langley <agl@google.com>
The channel_id_valid bit is both used for whether channel_id is filled
in (SSL_get_tls_channel_id), and whether this particular handshake will
eventually negotiate Channel ID.
The former means that, if SSL_get_tls_channel_id is called on the
client, we'll return all zeros. Apparently we never fill in channel_id
on the client at all. The latter means the state needs to be reset on
renegotiation because we do not currently forbid renegotiation with
Channel ID (we probably should...), which is the last use of the init
callback for extensions.
Instead, split this into a bit for the handshake and a bit for the
connection. Note this means we actually do not expose or even retain
whether Channel ID was used on the client.
This requires a tweak to the handoff logic, but it should be compatible.
The serialized ssl->s3->channel_id was always a no-op: the handback
happens before the ChannelID message, except in RSA key exchange. But we
forbid Channel ID in RSA key exchange anyway.
Update-Note: SSL_get_tls_channel_id will no longer return all zeros
during the handshake or on the client. I did not find any callers
relying on this.
Change-Id: Icd4b78dd3f311d1c7dfc1cae7d2b86dc7e327a99
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47906
Reviewed-by: Adam Langley <agl@google.com>
Also now that it's finalized, flip the default for
SSL_set_quic_use_legacy_codepoint.
Update-Note: QUIC APIs now default to the standard code point rather
than the draft one. QUICHE has already been calling
SSL_set_quic_use_legacy_codepoint, so this should not affect them. Once
callers implementing the draft versions cycle out, we can then drop
SSL_set_quic_use_legacy_codepoint altogether. I've also bumped
BORINGSSL_API_VERSION in case we end up needing an ifdef.
Change-Id: Id2cab66215f4ad4c1e31503d329c0febfdb4603e
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47864
Reviewed-by: David Schinazi <dschinazi@google.com>
Reviewed-by: Adam Langley <agl@google.com>
When decrypting a ticket we would copy the client's session ID into the
session and then copy the session's ID into the ServerHello (if
resuming). That seems icky. Instead install the same placeholder on the
server as we do on the client.
Change-Id: Icb50a3be2f05e6428f1b286c8c09015f7bb4af16
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47784
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
We didn't end up deploying this. We also never implemented the final
RFC, so what we do have isn't useful for someone who wishes to deploy
it anyway.
Update-Note: Token binding APIs are removed.
Change-Id: Iecea7c3dcf9d3e2644a3b7afaf61511310b45d5f
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47584
Reviewed-by: Adam Langley <agl@google.com>
This aligns with OpenSSL. In particular, we clear not_resumable as soon
as the SSL_SESSION is complete, but it may not have an ID or ticket.
(Due to APIs like SSL_get_session, SSL_SESSION needs to act both as a
resumption handle and a bundle of connection properties.)
Along the way, use the modified function in a few internal checks which,
with the ssl_update_cache change, removes the last dependency within the
library on the placeholder SHA256 IDs.
Change-Id: Ic225109ff31ec63ec08625e9f61a20cf0d9dd648
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47447
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
It's kind of weird that we assign a session ID, based on whether we
detect the handshake wants stateful resumption, and then erase it
afterwards.
Also remove the is_server parameter, which we can get from hs.
Change-Id: I94ac817c63abb08a457e0e0c29f5c2d2b60aa498
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47444
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Callers using private key callbacks may retain non-trivial state with a
private key. In many cases, the private key is no longer necessary
immediately after the first round-trip (e.g. non-HRR TLS 1.3
connections). Add a function that callers can query to drop the state a
hair earlier.
This is tested in two ways. First, the asserts in front of using the
key, combined with existing tests, ensure we don't start reporting it
too early. Second, I've added tests in ssl_test.cc to assert we report
it as early as we expect to.
In doing so, the number of parameters on ConnectClientAndServer()
started getting tedious, so I've split that into a
CreateClientAndServer() and CompleteHandshakes(). Callers that need to
configure weird things or drive the handshake manually can call
CreateClientAndServer() (which takes care of the BIO pair business) and
continue from there.
Bug: b/183734559
Change-Id: I05e1edb6d269c8468ba7cde7dc90e0856694a0ca
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47344
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
It's not even accurate. The term "master key" dates to SSL 2, which we
do not implement. (Starting SSL 3, "key" was replaced with "secret".)
The field stores, at various points, the TLS 1.2 master secret, the TLS
1.3 resumption master secret, and the TLS 1.3 resumption PSK. Simply
rename the field to 'secret', which is as descriptive of a name as we
can get at this point.
I've left SSL_SESSION_get_master_key alone for now, as it's there for
OpenSSL compatibility, as well as references to the various TLS secrets
since those refer to concepts in the spec. (When the dust settles a bit
on rfc8446bis, we can fix those.)
Change-Id: I3c1007eb7982788789cc5db851de8724c7f35baf
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/44144
Reviewed-by: Adam Langley <agl@google.com>
(Original CL by svaldez, reworked by davidben.)
Change-Id: I8570808fa5e96a1c9e6e03c4877039a22e73254f
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/42404
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
This function is still a bit too C-like, but this is slightly better.
Change-Id: Id8931753c9b8a2445d12089af5391833a68c4901
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/43004
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Adam Langley
David Benjamin
Steven Valdez