That we're half and half is really confusing.
Change-Id: I1c2632682e8a3e63d01dada8e0eb3b735ff709ce
Reviewed-on: https://boringssl-review.googlesource.com/6785
Reviewed-by: Adam Langley <agl@google.com>
This unifies the ClientKeyExchange code rather nicely. ServerKeyExchange
is still pretty specialized. For simplicity, I've extended the yaSSL bug
workaround for clients as well as servers rather than route in a
boolean.
Chrome's already banished DHE to a fallback with intention to remove
altogether later, and the spec doesn't say anything useful about
ClientDiffieHellmanPublic encoding, so this is unlikely to cause
problems.
Change-Id: I0355cd1fd0fab5729e8812e4427dd689124f53a2
Reviewed-on: https://boringssl-review.googlesource.com/6784
Reviewed-by: Adam Langley <agl@google.com>
The new curve is not enabled by default.
As EC_GROUP/EC_POINT is a bit too complex for X25519, this introduces an
SSL_ECDH_METHOD abstraction which wraps just the raw ECDH operation. It
also tidies up some of the curve code which kept converting back and
force between NIDs and curve IDs. Now everything transits as curve IDs
except for API entry points (SSL_set1_curves) which take NIDs. Those
convert immediately and act on curve IDs from then on.
Note that, like the Go implementation, this slightly tweaks the order of
operations. The client sees the server public key before sending its
own. To keep the abstraction simple, SSL_ECDH_METHOD expects to
generate a keypair before consuming the peer's public key. Instead, the
client handshake stashes the serialized peer public value and defers
parsing it until it comes time to send ClientKeyExchange. (This is
analogous to what it was doing before where it stashed the parsed peer
public value instead.)
It still uses TLS 1.2 terminology everywhere, but this abstraction should also
be compatible with TLS 1.3 which unifies (EC)DH-style key exchanges.
(Accordingly, this abstraction intentionally does not handle parsing the
ClientKeyExchange/ServerKeyExchange framing or attempt to handle asynchronous
plain RSA or the authentication bits.)
BUG=571231
Change-Id: Iba09dddee5bcdfeb2b70185308e8ab0632717932
Reviewed-on: https://boringssl-review.googlesource.com/6780
Reviewed-by: Adam Langley <agl@google.com>
In doing so, make the asynchronous portion look more like
ssl3_send_server_key_exchange. This is a considerably simpler structure,
so the save/resume doesn't need any state.
Mostly this means writing out the signature algorithm can now go through
CBB rather than a uint8_t* without bounds check.
Change-Id: If99fcffd0d41a84514c3d23034062c582f1bccb2
Reviewed-on: https://boringssl-review.googlesource.com/6771
Reviewed-by: Adam Langley <agl@google.com>
This relieves some complexity budget for adding Curve25519 to this
code.
This also adds a BN_bn2cbb_padded helper function since this seems to be a
fairly common need.
Change-Id: Ied0066fdaec9d02659abd6eb1a13f33502c9e198
Reviewed-on: https://boringssl-review.googlesource.com/6767
Reviewed-by: Adam Langley <agl@google.com>
This function may fail on malloc error.
Change-Id: I8631b1763dac5a3801fcaca81bdfcb8d24d3728c
Reviewed-on: https://boringssl-review.googlesource.com/6765
Reviewed-by: Adam Langley <agl@google.com>
This uses ssl3_read_bytes for now. We still need to dismantle that
function and then invert the handshake state machine, but this gets
things closer to the right shape as an intermediate step and is a large
chunk in itself. It simplifies a lot of the CCS/handshake
synchronization as a lot of the invariants much more clearly follow from
the handshake itself.
Tests need to be adjusted since this changes some error codes. Now all
the CCS/Handshake checks fall through to the usual
SSL_R_UNEXPECTED_RECORD codepath. Most of what used to be a special-case
falls out naturally. (If half of Finished was in the same record as the
pre-CCS message, that part of the handshake record would have been left
unconsumed, so read_change_cipher_spec would have noticed, just like
read_app_data would have noticed.)
Change-Id: I15c7501afe523d5062f0e24a3b65f053008d87be
Reviewed-on: https://boringssl-review.googlesource.com/6642
Reviewed-by: Adam Langley <agl@google.com>
Right now your options are:
- Bounce on a reference and deal with cleanup needlessly.
- Manually check the type tag and peek into the union.
We probably have no hope of opaquifying this struct, but for new code, let's
recommend using this function rather than the more error-prone thing.
Change-Id: I9b39ff95fe4264a3f7d1e0d2894db337aa968f6c
Reviewed-on: https://boringssl-review.googlesource.com/6551
Reviewed-by: Adam Langley <agl@google.com>
The keylog BIO is internally synchronized by the SSL_CTX lock, but an
application may wish to log keys from multiple SSL_CTXs. This is in
preparation for switching Chromium to use a separate SSL_CTX per profile
to more naturally split up the session caches.
It will also be useful for routing up SSLKEYLOGFILE in WebRTC. There,
each log line must be converted to an IPC up from the renderer
processes.
This will require changes in Chromium when we roll BoringSSL.
BUG=458365,webrtc:4417
Change-Id: I2945bdb4def0a9c36e751eab3d5b06c330d66b54
Reviewed-on: https://boringssl-review.googlesource.com/6514
Reviewed-by: Adam Langley <agl@google.com>
Until we've done away with the d2i_* stack completely, boundaries need
to be mindful of the type mismatch. d2i_* takes a long, not a size_t.
Change-Id: If02f9ca2cfde02d0929ac18275d09bf5df400f3a
Reviewed-on: https://boringssl-review.googlesource.com/6491
Reviewed-by: Adam Langley <agl@google.com>
dh.c had a 10k-bit limit but it wasn't quite correctly enforced. However,
that's still 1.12s of jank on the IO thread, which is too long. Since the SSL
code consumes DHE groups from the network, it should be responsible for
enforcing what sanity it needs on them.
Costs of various bit lengths on 2013 Macbook Air:
1024 - 1.4ms
2048 - 14ms
3072 - 24ms
4096 - 55ms
5000 - 160ms
10000 - 1.12s
UMA says that DHE groups are 0.2% 4096-bit and otherwise are 5.5% 2048-bit and
94% 1024-bit and some noise. Set the limit to 4096-bit to be conservative,
although that's already quite a lot of jank.
BUG=554295
Change-Id: I8e167748a67e4e1adfb62d73dfff094abfa7d215
Reviewed-on: https://boringssl-review.googlesource.com/6464
Reviewed-by: Adam Langley <agl@google.com>
The current check has two problems:
- It only runs on the server, where there isn't a curve list at all. This was a
mistake in https://boringssl-review.googlesource.com/1843 which flipped it
from client-only to server-only.
- It only runs in TLS 1.2, so one could bypass it by just negotiating TLS 1.1.
Upstream added it as part of their Suite B mode, which requires 1.2.
Move it elsewhere. Though we do not check the entire chain, leaving that to the
certificate verifier, signatures made by the leaf certificate are made by the
SSL/TLS stack, so it's reasonable to check the curve as part of checking
suitability of a leaf.
Change-Id: I7c12f2a32ba946a20e9ba6c70eff23bebcb60bb2
Reviewed-on: https://boringssl-review.googlesource.com/6414
Reviewed-by: Adam Langley <agl@google.com>
This exposes the ServerKeyExchange signature hash type used in the most recent
handshake, for histogramming on the client.
BUG=549662
Change-Id: I8a4e00ac735b1ecd2c2df824112c3a0bc62332a7
Reviewed-on: https://boringssl-review.googlesource.com/6413
Reviewed-by: Adam Langley <agl@google.com>
Later when TLS 1.3 comes around, we'll need SSL_CIPHER_get_max_version too. In
the meantime, hide the SSL_TLSV1_2 messiness behind a reasonable API.
Change-Id: Ibcc17cccf48dd99e364d6defdfa5a87d031ecf0a
Reviewed-on: https://boringssl-review.googlesource.com/6452
Reviewed-by: Adam Langley <agl@google.com>
Although the DTLS transport layer logic drops failed writes on the floor, it is
actually set up to work correctly. If an SSL_write fails at the transport,
dropping the buffer is fine. Arguably it works better than in TLS because we
don't have the weird "half-committed to data" behavior. Likewise, the handshake
keeps track of how far its gotten and resumes the message at the right point.
This broke when the buffering logic was rewritten because I didn't understand
what the DTLS code was doing. The one thing that doesn't work as one might
expect is non-fatal write errors during rexmit are not recoverable. The next
timeout must fire before we try again.
This code is quite badly sprinkled in here, so add tests to guard it against
future turbulence. Because of the rexmit issues, the tests need some hacks
around calls which may trigger them. It also changes the Go DTLS implementation
from being completely strict about sequence numbers to only requiring they be
monotonic.
The tests also revealed another bug. This one seems to be upstream's fault, not
mine. The logic to reset the handshake hash on the second ClientHello (in the
HelloVerifyRequest case) was a little overenthusiastic and breaks if the
ClientHello took multiple tries to send.
Change-Id: I9b38b93fff7ae62faf8e36c4beaf848850b3f4b9
Reviewed-on: https://boringssl-review.googlesource.com/6417
Reviewed-by: Adam Langley <agl@google.com>
These functions ultimately return the result of |BN_num_bits|, and that
function's return type is |unsigned|. Thus, these functions' return
type should also be |unsigned|.
Change-Id: I2cef63e6f75425857bac71f7c5517ef22ab2296b
Reviewed-on: https://boringssl-review.googlesource.com/6170
Reviewed-by: Adam Langley <alangley@gmail.com>
The internal session cache is keyed on session ID, so this is completely
useless for clients (indeed we never look it up internally). Along the way,
tidy up ssl_update_cache to be more readable. The slight behavior change is
that SSL_CTX_add_session's return code no longer controls the external
callback. It's not clear to me what that could have accomplished. (It can only
fail on allocation error. We only call it for new sessions, so the duplicate
case is impossible.)
The one thing of value the internal cache might have provided is managing the
timeout. The SSL_CTX_flush_sessions logic would flip the not_resumable bit and
cause us not to offer expired sessions (modulo SSL_CTX_flush_sessions's delay
and any discrepancies between the two caches). Instead, just check expiration
when deciding whether or not to offer a session.
This way clients that set SSL_SESS_CACHE_CLIENT blindly don't accidentally
consume gobs of memory.
BUG=531194
Change-Id: If97485beab21874f37737edc44df24e61ce23705
Reviewed-on: https://boringssl-review.googlesource.com/6321
Reviewed-by: Adam Langley <alangley@gmail.com>
A random 32-byte (so 256-bit) session ID is never going to collide with
an existing one. (And, if it does, SSL_CTX_add_session does account for
this, so the server won't explode. Just attempting to resume some
session will fail.)
That logic didn't completely work anyway as it didn't account for
external session caches or multiple connections picking the same ID in
parallel (generation and insertion happen at different times) or
multiple servers sharing one cache. In theory one could fix this by
passing in a sufficiently clever generate_session_id, but no one does
that.
I found no callers of these functions, so just remove them altogether.
Change-Id: I8500c592cf4676de6d7194d611b99e9e76f150a7
Reviewed-on: https://boringssl-review.googlesource.com/6318
Reviewed-by: Adam Langley <alangley@gmail.com>
This callback is some combination of arguably useful stuff (bracket
handshakes, alerts) and completely insane things (find out when the
state machine advances). Deprecate the latter.
Change-Id: Ibea5b32cb360b767b0f45b302fd5f1fe17850593
Reviewed-on: https://boringssl-review.googlesource.com/6305
Reviewed-by: Adam Langley <alangley@gmail.com>
RFC 5077 explicitly allows the server to change its mind and send no
ticket by sending an empty NewSessionTicket. See also upstream's
21b538d616b388fa0ce64ef54da3504253895cf8.
CBS_stow handles this case somewhat, so we won't get confused about
malloc(0) as upstream did. But we'll still fill in a bogus SHA-256
session ID, cache the session, and send a ClientHello with bogus session
ID but empty ticket extension. (The session ID field changes meaning
significantly when the ticket is or isn't empty. Non-empty means "ignore
the session ID, but echo if it resuming" while empty means "I support
tickets, but am offering this session ID".
The other behavior change is that a server which changes its mind on a
resumption handshake will no longer override the client's session cache
with a ticket-less session.
(This is kind of silly. Given that we don't get completely confused due
to CBS_stow, it might not be worth bothering with the rest. Mostly it
bugged me that we send an indicator session ID with no ticket.)
Change-Id: Id6b5bde1fe51aa3e1f453a948e59bfd1e2502db6
Reviewed-on: https://boringssl-review.googlesource.com/6340
Reviewed-by: Adam Langley <alangley@gmail.com>
In doing so, simplify the mess around serializing the public key.
Channel ID specifies that you write x and y concatenated. Rather than
using the X9.62 serialization and chopping bits off, get the affine
coordinates and write them out in the same way we write r and s.
Also unify the P-256 sanity check around SSL_set1_tls_channel_id and
actually check the curve NID.
BUG=468889
Change-Id: I228877b736c9722e368d315064ce3ae6893adfc0
Reviewed-on: https://boringssl-review.googlesource.com/6201
Reviewed-by: Adam Langley <alangley@gmail.com>
Start converting the ones we can right now. Some of the messier ones
resize init_buf rather than assume the initial size is sufficient, so
those will probably wait until init_buf is gone and the handshake's
undergone some more invasive surgery. The async ones will also require
some thought. But some can be incrementally converted now.
BUG=468889
Change-Id: I0bc22e4dca37d9d671a488c42eba864c51933638
Reviewed-on: https://boringssl-review.googlesource.com/6190
Reviewed-by: Adam Langley <alangley@gmail.com>
Deprecate the client_cert_cb variant since you can't really configure
intermediates with it. (You might be able to by configuring the
intermediates without the leaf or key and leaving the SSL stack to
configure those, but that's really weird. cert_cb is simpler.)
Also document the two functions the callbacks may use to query the
CertificateRequest on the client.
Change-Id: Iad6076266fd798cd74ea4e09978e7f5df5c8a670
Reviewed-on: https://boringssl-review.googlesource.com/6092
Reviewed-by: Adam Langley <agl@google.com>
Allow configuring digest preferences for the private key. Some
smartcards have limited support for signing digests, notably Windows
CAPI keys and old Estonian smartcards. Chromium used the supports_digest
hook in SSL_PRIVATE_KEY_METHOD to limit such keys to SHA1. However,
detecting those keys was a heuristic, so some SHA256-capable keys
authenticating to SHA256-only servers regressed in the switch to
BoringSSL. Replace this mechanism with an API to configure digest
preference order. This way heuristically-detected SHA1-only keys may be
configured by Chromium as SHA1-preferring rather than SHA1-requiring.
In doing so, clean up the shared_sigalgs machinery somewhat.
BUG=468076
Change-Id: I996a2df213ae4d8b4062f0ab85b15262ca26f3c6
Reviewed-on: https://boringssl-review.googlesource.com/5755
Reviewed-by: Adam Langley <agl@google.com>
ssl.h should be first. Also two lines after includes and the rest of the
file.
Change-Id: Icb7586e00a3e64170082c96cf3f8bfbb2b7e1611
Reviewed-on: https://boringssl-review.googlesource.com/5892
Reviewed-by: Adam Langley <agl@google.com>
Applications may require the stapled OCSP response in order to verify
the certificate within the verification callback.
Change-Id: I8002e527f90c3ce7b6a66e3203c0a68371aac5ec
Reviewed-on: https://boringssl-review.googlesource.com/5730
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
Move cert_chain to the SSL_SESSION. Now everything on an SSL_SESSION is
properly serialized. The cert_chain field is, unfortunately, messed up
since it means different things between client and server.
There exists code which calls SSL_get_peer_cert_chain as both client and
server and assumes the existing semantics for each. Since that function
doesn't return a newly-allocated STACK_OF(X509), normalizing between the
two formats is a nuisance (we'd either need to store both cert_chain and
cert_chain_full on the SSL_SESSION or create one of the two variants
on-demand and stash it into the SSL).
This CL does not resolve this and retains the client/server difference
in SSL_SESSION. The SSL_SESSION serialization is a little inefficient
(two copies of the leaf certificate) for a client, but clients don't
typically serialize sessions. Should we wish to resolve it in the
future, we can use a different tag number. Because this was historically
unserialized, existing code must already allow for cert_chain not being
preserved across i2d/d2i.
In keeping with the semantics of retain_only_sha256_of_client_certs,
cert_chain is not retained when that flag is set.
Change-Id: Ieb72fc62c3076dd59750219e550902f1ad039651
Reviewed-on: https://boringssl-review.googlesource.com/5759
Reviewed-by: Adam Langley <agl@google.com>
It's completely redundant with the copy in the SSL_SESSION except it
isn't serialized.
Change-Id: I1d95a14cae064c599e4bab576df1dd156da4b81c
Reviewed-on: https://boringssl-review.googlesource.com/5757
Reviewed-by: Adam Langley <agl@google.com>
Gets another field out of the SSL_SESSION.
Change-Id: I9a27255533f8e43e152808427466ec1306cfcc60
Reviewed-on: https://boringssl-review.googlesource.com/5756
Reviewed-by: Adam Langley <agl@google.com>
This change stores the size of the group/modulus (for RSA/DHE) or curve
ID (for ECDHE) in the |SSL_SESSION|. This makes it available for UIs
where desired.
Change-Id: I354141da432a08f71704c9683f298b361362483d
Reviewed-on: https://boringssl-review.googlesource.com/5280
Reviewed-by: Adam Langley <agl@google.com>
Rather than iterate over handshake_dgsts itself, it can just call
tls1_handshake_digest.
Change-Id: Ia518da540e47e65b13367eb1af184c0885908488
Reviewed-on: https://boringssl-review.googlesource.com/5617
Reviewed-by: Adam Langley <agl@google.com>
The handshake hash is initialized from the buffer as soon as the cipher
is known. When adding a message to the transcript, independently update
the buffer and rolling hash, whichever is active. This avoids the
complications around dont_free_handshake_buffer and EMS.
BUG=492371
Change-Id: I3b1065796a50fd1be5d42ead7210c2f253ef0aca
Reviewed-on: https://boringssl-review.googlesource.com/5615
Reviewed-by: Adam Langley <agl@google.com>
The RSA key exchange needs decryption and is still unsupported.
Change-Id: I8c13b74e25a5424356afbe6e97b5f700a56de41f
Reviewed-on: https://boringssl-review.googlesource.com/5467
Reviewed-by: Adam Langley <agl@google.com>
This also removes support for the “old” Channel ID extension.
Change-Id: I1168efb9365c274db6b9d7e32013336e4404ff54
Reviewed-on: https://boringssl-review.googlesource.com/5462
Reviewed-by: Adam Langley <agl@google.com>
This allows us to remove the confusing EVP_PKEY argument to the
SSL_PRIVATE_KEY_METHOD wrapper functions. It also simplifies some of the
book-keeping around the CERT structure, as well as the API for
configuring certificates themselves. The current one is a little odd as
some functions automatically route to the slot while others affect the
most recently touched slot. Others still (extra_certs) apply to all
slots, making them not terribly useful.
Consumers with complex needs should use cert_cb or the early callback
(select_certificate_cb) to configure whatever they like based on the
ClientHello.
BUG=486295
Change-Id: Ice29ffeb867fa4959898b70dfc50fc00137f01f3
Reviewed-on: https://boringssl-review.googlesource.com/5351
Reviewed-by: Adam Langley <agl@google.com>
After the custom key method support, the EVP_PKEY parameter is somewhat
confusing (to be resolved with the certificate slots removal) as it must
always refer to a private key. ssl3_cert_verify_hash is sometimes used
with the peer's public key. If custom keys were supported on the server,
this would break.
Fix this by passing a pkey_type parameter and letting the caller decide
whether this uses SSL_PRIVATE_KEY_METHOD or not.
Change-Id: I673b92579a84b4561f28026ec0b1c78a6bfee440
Reviewed-on: https://boringssl-review.googlesource.com/5341
Reviewed-by: Adam Langley <agl@google.com>
If ssl_do_write takes more than one iteration, ssl3_output_cert_chain
would be called an extra time. This is very unlikely in practice because
of the buffer BIO.
Change-Id: Ic1ae9752a8837bb404429fc60306c659208c6185
Reviewed-on: https://boringssl-review.googlesource.com/5340
Reviewed-by: Adam Langley <agl@google.com>
One tedious thing about using CBB is that you can't safely CBB_cleanup
until CBB_init is successful, which breaks the general 'goto err' style
of cleanup. This makes it possible:
CBB_zero ~ EVP_MD_CTX_init
CBB_init ~ EVP_DigestInit
CBB_cleanup ~ EVP_MD_CTX_cleanup
Change-Id: I085ecc4405715368886dc4de02285a47e7fc4c52
Reviewed-on: https://boringssl-review.googlesource.com/5267
Reviewed-by: Adam Langley <agl@google.com>
Rather than parse with d2i_ECDSA_SIG and reserialize, this is cleaner.
It's also clearer that i2d_PublicKey isn't being used for DER.
Change-Id: Iac57fb6badd1dfed1e66984e95a31f609b1538a4
Reviewed-on: https://boringssl-review.googlesource.com/5263
Reviewed-by: Adam Langley <agl@google.com>
Rather than rely on Chromium to query SSL_initial_handshake_complete in the
callback (which didn't work anyway because the callback is called afterwards),
move the logic into BoringSSL. BoringSSL already enforces that clients never
offer resumptions on renegotiation (it wouldn't work well anyway as client
session cache lookup is external), so it's reasonable to also implement
in-library that sessions established on a renegotiation are not cached.
Add a bunch of tests that new_session_cb is called when expected.
BUG=501418
Change-Id: I42d44c82b043af72b60a0f8fdb57799e20f13ed5
Reviewed-on: https://boringssl-review.googlesource.com/5171
Reviewed-by: Adam Langley <agl@google.com>
This adds a new API, SSL_set_private_key_method, which allows the consumer to
customize private key operations. For simplicity, it is incompatible with the
multiple slots feature (which will hopefully go away) but does not, for now,
break it.
The new method is only routed up for the client for now. The server will
require a decrypt hook as well for the plain RSA key exchange.
BUG=347404
Change-Id: I35d69095c29134c34c2af88c613ad557d6957614
Reviewed-on: https://boringssl-review.googlesource.com/5049
Reviewed-by: Adam Langley <agl@google.com>
Turns out the safer/simpler method still wasn't quite right. :-)
session->sess_cert isn't serialized and deserialized, which is poor. Duplicate
it manually for now. Leave a TODO to get rid of that field altogether as it's
not especially helpful. The certificate-related fields should be in the
session. The others probably have no reason to be preserved on resumptions at
all.
Test by making bssl_shim.cc assert the peer cert chain is there or not as
expected.
BUG=501220
Change-Id: I44034167629720d6e2b7b0b938d58bcab3ab0abe
Reviewed-on: https://boringssl-review.googlesource.com/5170
Reviewed-by: Adam Langley <agl@google.com>
See also upstream's 27c76b9b8010b536687318739c6f631ce4194688, CVE-2015-1791.
Rather than write a dup function, serializing and deserializing the object is
simpler. It also fixes a bug in the original fix where it never calls
new_session_cb to store the new session (for clients which use that callback;
how clients should handle the session cache is much less clear).
The old session isn't pruned as we haven't processed the Finished message yet.
RFC 5077 says:
The server MUST NOT assume that the client actually received the updated
ticket until it successfully verifies the client's Finished message.
Moreover, because network messages are asynchronous, a new SSL connection may
have began just before the client received the new ticket, so any such servers
are broken regardless.
Change-Id: I13b3dc986dc58ea2ce66659dbb29e14cd02a641b
Reviewed-on: https://boringssl-review.googlesource.com/5122
Reviewed-by: Adam Langley <agl@google.com>
Mirrors SSL_SESSION_to_bytes. It avoids having to deal with object-reuse, the
non-size_t length parameter, and trailing data. Both it and the object-reuse
variant back onto an unexposed SSL_SESSION_parse which reads a CBS.
Note that this changes the object reuse story slightly. It's now merely an
optional output pointer that frees its old contents. No d2i_SSL_SESSION
consumer in Google that's built does reuse, much less reuse with the assumption
that the top-level object won't be overridden.
Change-Id: I5cb8522f96909bb222cab0f342423f2dd7814282
Reviewed-on: https://boringssl-review.googlesource.com/5121
Reviewed-by: Adam Langley <agl@google.com>
