On the TLS side, we introduce a running buffer of ciphertext. Queuing up
pending data consists of encrypting the record into the buffer. This
effectively reimplements what the buffer BIO was doing previously, but
this resizes to fit the whole flight.
As part of this, rename all the functions to add to the pending flight
to be more uniform. This CL proposes "add_foo" to add to the pending
flight and "flush_flight" to drain it.
We add an add_alert hook for alerts but, for now, only the SSL 3.0
warning alert (sent mid-handshake) uses this mechanism. Later work will
push this down to the rest of the write path so closure alerts use it
too, as in DTLS. The intended end state is that all the ssl_buffer.c and
wpend_ret logic will only be used for application data and eventually
optionally replaced by the in-place API, while all "incidental" data
will be handled internally.
For now, the two buffers are mutually exclusive. Moving closure alerts
to "incidentals" will change this, but flushing application data early
is tricky due to wpend_ret. (If we call ssl_write_buffer_flush,
do_ssl3_write doesn't realize it still has a wpend_ret to replay.) That
too is all left alone in this change.
To keep the diff down, write_message is retained for now and will be
removed from the state machines in a follow-up change.
BUG=72
Change-Id: Ibce882f5f7196880648f25d5005322ca4055c71d
Reviewed-on: https://boringssl-review.googlesource.com/13224
Reviewed-by: Adam Langley <agl@google.com>
Instead, "writing" a message merely adds it to the outgoing_messages
structure. The code to write the flight then loops over it all and now
shares code with retransmission. The verbs here are all a little odd,
but they'll be fixed in later commits.
In doing so, this fixes a slight miscalculation of the record-layer
overhead when retransmitting a flight that spans two epochs. (We'd use
the encrypted epoch's overhead for the unencrypted epoch.)
BUG=72
Change-Id: I8ac897c955cc74799f8b5ca6923906e97d6dad17
Reviewed-on: https://boringssl-review.googlesource.com/13223
Reviewed-by: Adam Langley <agl@google.com>
These are no longer used anywhere.
Change-Id: Id79299f92c705f6bb7aed7acb48994d4498bd2d8
Reviewed-on: https://boringssl-review.googlesource.com/13341
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Change-Id: Ifc28887cbf91c7a80bdaf56e3bf80b2f8cfa7d53
Reviewed-on: https://boringssl-review.googlesource.com/13260
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
It's not completely clear to me why select_cetificate_cb behaves the way it
does, however not only is it confusing, but it makes assumptions about the
application using BoringSSL (it's not always possible to implement custom
logic outside of the callbacks provided by libssl), that make this callback
somewhat useless.
Case in point, the callback can be used for changing min/max protocol versions
based on per-site policies, and select_certificate_cb is the only place where
SSL_set_min/max_proto_version() can be used (e.g. you can't call them in
cert_cb because it's too late), but the decision on the specific versions to
use might depend on configuration that needs retrieving asynchronously from
over the network, which requires re-running the callback multiple times.
Change-Id: Ia8e151b163628545373e7fd1f327e9af207478a6
Reviewed-on: https://boringssl-review.googlesource.com/13000
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
We have a test somewhere which tries to read off of it. Align the getter
roughly with upstream's SSL_SESSION_get0_id_context (which we don't
currently expose).
BUG=6
Change-Id: Iab240868838ba56c1f08d112888d9536574347b4
Reviewed-on: https://boringssl-review.googlesource.com/12636
Reviewed-by: David Benjamin <davidben@google.com>
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Before RFC 7539 we had a ChaCha20-Poly1305 cipher suite that had a 64/64
nonce/counter split (as DJB's original ChaCha20 did). RFC 7539 changed
that to 96/32 and we've supported both for some time.
This change removes the old version and the TLS cipher suites that used
it.
BUG=chromium:682816
Change-Id: I2345d6db83441691fe0c1ab6d7c6da4d24777849
Reviewed-on: https://boringssl-review.googlesource.com/13203
Reviewed-by: Adam Langley <agl@google.com>
This reverts commit def9b46801.
(I should have uploaded a new version before sending to the commit queue.)
Change-Id: Iaead89c8d7fc1f56e6294d869db9238b467f520a
Reviewed-on: https://boringssl-review.googlesource.com/13202
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TLS 1.3 forbids warning alerts, and sending these is a bad idea. Per RFC
6066:
If the server understood the ClientHello extension but
does not recognize the server name, the server SHOULD take one of two
actions: either abort the handshake by sending a fatal-level
unrecognized_name(112) alert or continue the handshake. It is NOT
RECOMMENDED to send a warning-level unrecognized_name(112) alert,
because the client's behavior in response to warning-level alerts is
unpredictable.
The motivation is to cut down on the number of places where we send
non-closing alerts. We can't remove them yet (SSL 3.0 and TLS 1.3 draft
18 need to go), but eventually this can be a simplifying assumption.
Already this means DTLS never sends warning alerts, which is good
because DTLS can't retransmit them.
Change-Id: I577a1eb9c23e66d28235c0fbe913f00965e19486
Reviewed-on: https://boringssl-review.googlesource.com/13221
Reviewed-by: Adam Langley <agl@google.com>
Before RFC 7539 we had a ChaCha20-Poly1305 cipher suite that had a 64/64
nonce/counter split (as DJB's original ChaCha20 did). RFC 7539 changed
that to 96/32 and we've supported both for some time.
This change removes the old version and the TLS cipher suites that used
it.
Change-Id: Icd9c2117c657f3aa6df55990c618d562194ef0e8
Reviewed-on: https://boringssl-review.googlesource.com/13201
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
Change-Id: Ia6598ee4b2d4623abfc140d6a5c0eca4bcb30427
Reviewed-on: https://boringssl-review.googlesource.com/13180
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These are no longer needed.
Change-Id: I909f7d690f57dafcdad6254948b5683757da69f4
Reviewed-on: https://boringssl-review.googlesource.com/13160
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
This change adds the OS-specific routines to get random bytes when using
BoringSSL on Fuchsia. Fuchsia uses the Magenta kernel, which provides
random bytes via a syscall rather than via a file or library function.
Change-Id: I32f858246425309d643d142214c7b8de0c62250a
Reviewed-on: https://boringssl-review.googlesource.com/13140
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The last one was an RC4 cipher and those are gone.
Change-Id: I3473937ff6f0634296fc75a346627513c5970ddb
Reviewed-on: https://boringssl-review.googlesource.com/13108
Reviewed-by: Adam Langley <agl@google.com>
BN_FLG_CONSTTIME is a ridiculous API and easy to mess up
(CVE-2016-2178). Instead, code that needs a particular algorithm which
preserves secrecy of some arguemnt should call into that algorithm
directly.
This is never set outside the library and is finally unused within the
library! Credit for all this goes almost entirely to Brian Smith. I just
took care of the last bits.
Note there was one BN_FLG_CONSTTIME check that was still reachable, the
BN_mod_inverse in RSA key generation. However, it used the same code in
both cases for even moduli and φ(n) is even if n is not a power of two.
Traditionally, RSA keys are not powers of two, even though it would make
the modular reductions a lot easier.
When reviewing, check that I didn't remove a BN_FLG_CONSTTIME that led
to a BN_mod_exp(_mont) or BN_mod_inverse call (with the exception of the
RSA one mentioned above). They should all go to functions for the
algorithms themselves like BN_mod_exp_mont_consttime.
This CL shows the checks are a no-op for all our tests:
https://boringssl-review.googlesource.com/c/12927/
BUG=125
Change-Id: I19cbb375cc75aac202bd76b51ca098841d84f337
Reviewed-on: https://boringssl-review.googlesource.com/12926
Reviewed-by: Adam Langley <alangley@gmail.com>
TLS 1.3 doesn't support renegotiation in the first place, but so callers
don't report TLS 1.3 servers as missing it, always report it as
(vacuously) protected against this bug.
BUG=chromium:680281
Change-Id: Ibfec03102b2aec7eaa773c331d6844292e7bb685
Reviewed-on: https://boringssl-review.googlesource.com/13046
Reviewed-by: David Benjamin <davidben@google.com>
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Change-Id: Iad9b0898b3a602fc2e554c4fd59a599c61cd8ef7
Reviewed-on: https://boringssl-review.googlesource.com/13063
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <alangley@gmail.com>
They're not called externally. Unexporting these will make it easier to
rewrite the PKCS{5,8,12} code to use CBS/CBB rather than X509_ALGOR.
Getting rid of those callers in Chromium probably won't happen for a
while since it's in our on-disk formats. (And a unit test for some NSS
client cert glue uses it.)
BUG=54
Change-Id: Id4148a2ad567484782a6e0322b68dde0619159fc
Reviewed-on: https://boringssl-review.googlesource.com/13062
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <alangley@gmail.com>
Towards an eventual goal of opaquifying BoringSSL structs, we want
our consumers -- in this case, Android's libcore -- to not directly
manipulate BigNums; and it would be convenient for them if we would
perform the appropriate gymnastics to interpret little-endian byte
streams.
It also seems a priori a bit strange to have only big-endian varieties
of BN byte-conversions.
This CL provides little-endian equivalents of BN_bn2bin_padded
and BN_bin2bn.
BUG=97
Change-Id: I0e92483286def86d9bd71a46d6a967a3be50f80b
Reviewed-on: https://boringssl-review.googlesource.com/12641
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This adds support for setting 0-RTT mode on tickets minted by
BoringSSL, allowing for testing of the initial handshake knowledge.
BUG=76
Change-Id: Ic199842c03b5401ef122a537fdb7ed9e9a5c635a
Reviewed-on: https://boringssl-review.googlesource.com/12740
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This is a memory error for anything other than LHASH_OF(char), which
does not exist.
No code outside the library creates (or even queries) an LHASH, so we
can change this module freely.
Change-Id: Ifbc7a1c69a859e07650fcfaa067bdfc68d83fbbc
Reviewed-on: https://boringssl-review.googlesource.com/12978
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
BUG=97
Change-Id: I4799cc99511e73af44def1d4daa36a8b4699f62d
Reviewed-on: https://boringssl-review.googlesource.com/12904
Reviewed-by: David Benjamin <davidben@google.com>
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The perl script is a little nuts. obj_dat.pl actually parses the header
file that objects.pl emits to figure out what all the objects are.
Replace it all with a single Go script.
BUG=16
Change-Id: Ib1492e22dbe4cf9cf84db7648612b156bcec8e63
Reviewed-on: https://boringssl-review.googlesource.com/12963
Reviewed-by: Adam Langley <agl@google.com>
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This extension will be used to test whether
https://github.com/tlswg/tls13-spec/pull/762 is deployable against
middleboxes. For simplicity, it is mutually exclusive with 0-RTT. If
client and server agree on the extension, TLS 1.3 records will use the
format in the PR rather than what is in draft 18.
BUG=119
Change-Id: I1372ddf7b328ddf73d496df54ac03a95ede961e1
Reviewed-on: https://boringssl-review.googlesource.com/12684
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X509_STORE_set0_additional_untrusted allows one to set a stack of
additional untrusted certificates that can be used during chain
building. These will be merged with the untrusted certificates set on
the |X509_STORE_CTX|.
Change-Id: I3f011fb0854e16a883a798356af0a24cbc5a9d68
Reviewed-on: https://boringssl-review.googlesource.com/12980
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Simplify the code, and in particular make |BN_div|, |BN_mod|, and
|BN_nnmod| insensitive to |BN_FLG_CONSTTIME|. This improves the
effectiveness of testing by reducing the number of branches that are
likely to go untested or less tested.
There is no performance-sensitive code that uses BN_div but doesn't
already use BN_FLG_CONSTTIME except RSA signature verification and
EC_GROUP creation. RSA signature verification, ECDH, and ECDSA
performance aren't significantly different with this change.
Change-Id: Ie34c4ce925b939150529400cc60e1f414c7676cd
Reviewed-on: https://boringssl-review.googlesource.com/9105
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
There are no longer any consumers of these APIs.
These were useful back when the CBC vs. RC4 tradeoff varied by version
and it was worth carefully tuning this cutoff. Nowadays RC4 is
completely gone and there's no use in configuring these anymore.
To avoid invalidating the existing ssl_ctx_api corpus and requiring it
regenerated, I've left the entries in there. It's probably reasonable
for new API fuzzers to reuse those slots.
Change-Id: I02bf950e3828062341e4e45c8871a44597ae93d5
Reviewed-on: https://boringssl-review.googlesource.com/12880
Commit-Queue: David Benjamin <davidben@google.com>
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-2 is really weird. On sign, it's maximal length. On verify, it actually
accepts all lengths. This sounds somewhat questionable to me, but just
document the state of the world for now. Also add a recommendation to
use -1 (match digest length) to align with TLS 1.3, tokbind, and QUIC
Crypto. Hopefully the first two is sufficient that the IETF will forever
use this option and stop the proliferation of RSA-PSS parameters.
Change-Id: Ie0ad7ad451089df0e18d6413d1b21c5aaad9d0f2
Reviewed-on: https://boringssl-review.googlesource.com/12823
Commit-Queue: David Benjamin <davidben@google.com>
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This function always returns the full chain and will hopefully eliminate
the need for some code in Conscrypt.
Change-Id: Ib662005322c40824edf09d100a784ff00492896a
Reviewed-on: https://boringssl-review.googlesource.com/12780
Reviewed-by: Adam Langley <agl@google.com>
Querying a bit in a BIT STRING is a little finicky. Add some functions
to help with this.
Change-Id: I813b9b6f2d952d61d8717b47bca1344f0ad4b7d1
Reviewed-on: https://boringssl-review.googlesource.com/12800
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So we can report it cleanly out of DevTools, it should behave like
SSL_get_curve_id and be reported on resumption too.
BUG=chromium:658905
Change-Id: I0402e540a1e722e09eaebadf7fb4785d8880c389
Reviewed-on: https://boringssl-review.googlesource.com/12694
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The only accessor for this field is the group/curve ID. Switch to only
storing that so no cipher checks are needed to interpret it. Instead,
ignore older values at parse time.
Change-Id: Id0946d4ac9e7482c69e64cc368a9d0cddf328bd3
Reviewed-on: https://boringssl-review.googlesource.com/12693
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Nothing calls this anymore. DHE is nearly gone. This unblocks us from
making key_exchange_info only apply to the curve.
Change-Id: I3099e7222a62441df6e01411767d48166a0729b1
Reviewed-on: https://boringssl-review.googlesource.com/12691
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This change removes the use of |X509_get_pubkey| from the TLS <= 1.2
code. That function is replaced with a shallow parse of the certificate
to extract the public key instead.
Change-Id: I8938c6c5a01b32038c6b6fa58eb065e5b44ca6d2
Reviewed-on: https://boringssl-review.googlesource.com/12707
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This currently only works for certificates parsed from the network, but
if making several connections that share certificates, some KB of memory
might be saved.
BUG=chromium:671420
Change-Id: I1c7a71d84e1976138641f71830aafff87f795f9d
Reviewed-on: https://boringssl-review.googlesource.com/12706
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This change adds a STACK_OF(CRYPTO_BUFFER) to an SSL_SESSION which
contains the raw form of the received certificates. The X509-based
members still exist, but their |enc| buffer will alias the
CRYPTO_BUFFERs.
(This is a second attempt at
https://boringssl-review.googlesource.com/#/c/12163/.)
BUG=chromium:671420
Change-Id: I508a8a46cab89a5a3fcc0c1224185d63e3d59cb8
Reviewed-on: https://boringssl-review.googlesource.com/12705
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OpenSSL includes a leaf certificate in a certificate chain when it's a
client, but doesn't when it's a server. This is also reflected in the
serialisation of sessions.
This change makes the internal semantics consistent: the leaf is always
included in the chain in memory, and never duplicated when serialised.
To maintain the same API, SSL_get_peer_cert_chain will construct a copy
of the chain without the leaf if needed.
Since the serialised format of a client session has changed, an
|is_server| boolean is added to the ASN.1 that defaults to true. Thus
any old client sessions will be parsed as server sessions and (silently)
discarded by a client.
Change-Id: Ibcf72bc8a130cedb423bc0fd3417868e0af3ca3e
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state is now initialized to SSL_ST_INIT in SSL_HANDSHAKE. If there is no
handshake present, we report SSL_ST_OK. This saves 8 bytes of
per-connection post-handshake memory.
Change-Id: Idb3f7031045caed005bd7712bc8c4b42c81a1d04
Reviewed-on: https://boringssl-review.googlesource.com/12697
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This avoids needing a extra state around client certificates to avoid
calling the callbacks twice. This does, however, come with a behavior
change: configuring both callbacks won't work. No consumer does this.
(Except bssl_shim which needed slight tweaks.)
Change-Id: Ia5426ed2620e40eecdcf352216c4a46764e31a9a
Reviewed-on: https://boringssl-review.googlesource.com/12690
Reviewed-by: Adam Langley <agl@google.com>
This is never used. Removing it allows us to implement the old callback
using the new one.
Change-Id: I4be70cc16e609ce79b51836c19fec565c67ff3d6
Reviewed-on: https://boringssl-review.googlesource.com/12689
Commit-Queue: David Benjamin <davidben@google.com>
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Callers doing more interesting things than read and write tend to use
SSL_get_error. SSL_want_{read,write} are still used, however.
Change-Id: I21e83cc8046742857051f755868d86deffd23d81
Reviewed-on: https://boringssl-review.googlesource.com/12688
Commit-Queue: David Benjamin <davidben@google.com>
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One of them is used in the new minimal SSL BIO, but cURL doesn't consume
it, so let's just leave it out. A consumer using asynchronous
certificate lookup is unlikely to be doing anything with SSL BIOs.
Change-Id: I10e7bfd643d3a531d42a96a8d675611d13722bd2
Reviewed-on: https://boringssl-review.googlesource.com/12686
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For folks who prefer the named length constants, the current ones aren't
sufficient because the shared key isn't the private key or a public
value.
Well, it does have the same type as a public value, but it looks silly
to write:
uint8_t secret_key[X25519_PUBLIC_VALUE_LEN];
Change-Id: I391db8ee73e2b4305d0ddd22f6d99f6abbc6b45b
Reviewed-on: https://boringssl-review.googlesource.com/12680
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Change-Id: Iaac633616a54ba1ed04c14e4778865c169a68621
Reviewed-on: https://boringssl-review.googlesource.com/12703
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This reverts commits 5a6e616961 and
e8509090cf. I'm going to unify how the
chains are kept in memory between client and server first otherwise the
mess just keeps growing.
Change-Id: I76df0d94c9053b2454821d22a3c97951b6419831
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Change-Id: Ie947ab176d10feb709c6e135d5241c6cf605b8e8
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CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
This currently only works for certificates parsed from the network, but
if making several connections that share certificates, some KB of memory
might be saved.
Change-Id: I0ea4589d7a8b5c41df225ad7f282b6d1376a8db4
Reviewed-on: https://boringssl-review.googlesource.com/12164
Reviewed-by: Adam Langley <alangley@gmail.com>
