SSL_clear() does not reset the SSL_METHOD if a session already exists in
the SSL object. However, TLSv1.3 does not have an externally visible
version fixed method (only an internal one). The state machine assumes
that we are always starting from a version flexible method for TLSv1.3.
The simplest solution is to just fix SSL_clear() to always reset the method
if it is using the internal TLSv1.3 version fixed method.
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/3954)
If the result of a SSL_{CTX_,}set_{min,max}_proto_version() call
leaves the min and max version identical, and support for that version
is compiled out of the library, return an error. Such an object has
no hope of successfully completing a handshake, and this error may
be easier to decipher than the resulting handshake failure.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3422)
It is an API to be used from the early callback that indicates what
extensions were present in the ClientHello, and in what order.
This can be used to eliminate unneeded calls to SSL_early_get0_ext()
(which itself scales linearly in the number of extensions supported
by the library).
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2976)
We are quite inconsistent about which alerts get sent. Specifically, these
alerts should be used (normally) in the following circumstances:
SSL_AD_DECODE_ERROR = The peer sent a syntactically incorrect message
SSL_AD_ILLEGAL_PARAMETER = The peer sent a message which was syntactically
correct, but a parameter given is invalid for the context
SSL_AD_HANDSHAKE_FAILURE = The peer's messages were syntactically and
semantically correct, but the parameters provided were unacceptable to us
(e.g. because we do not support the requested parameters)
SSL_AD_INTERNAL_ERROR = We messed up (e.g. malloc failure)
The standards themselves aren't always consistent but I think the above
represents the best interpretation.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3480)
The function SSL_set_SSL_CTX() can be used to swap the SSL_CTX used for
a connection as part of an SNI callback. One result of this is that the
s->cert structure is replaced. However this structure contains information
about any custom extensions that have been loaded. In particular flags are
set indicating whether a particular extension has been received in the
ClientHello. By replacing the s->cert structure we lose the custom
extension flag values, and it appears as if a client has not sent those
extensions.
SSL_set_SSL_CTX() should copy any flags for custom extensions that appear
in both the old and the new cert structure.
Fixes#2180
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3425)
Add padding callback for application control
Standard block_size callback
Documentation and tests included
Configuration file/s_client/s_srver option
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3130)
ECDHE is not properly defined for SSLv3. Commit fe55c4a2 prevented ECDHE
from being selected in that protocol. However, historically, servers do
still select ECDHE anyway so that commit causes interoperability problems.
Clients that previously worked when talking to an SSLv3 server could now
fail.
This commit introduces an exception which enables a client to continue in
SSLv3 if the server selected ECDHE.
[extended tests]
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3204)
This resulted in the SCT timestamp check always failing, because the
timestamp appeared to be in the future.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3138)
Add functions to add/retrieve the certificate_authorities. The older
client_CA functions mainly just call the new versions now.
Rename fields sice new extension can be generated by client and server.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3015)
SSL_get_max_early_data() recently added by 3fc8d85610 ("Construct the
ticket_early_data_info extension", 2017-02-17) is supposed to take an
SSL, but it doesn't.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3113)
If the server received EoED then SSL_read_early_data() will return
SSL_READ_EARLY_DATA_FINISH. However if the CF has not yet been processed
then SSL_is_init_finished() will still return 0. Therefore we should still
be able to write early data.
Fixes#3041
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3089)
Fix some comments too
[skip ci]
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3069)
The end of early data is now indicated by a new handshake message rather
than an alert.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2895)
Also updates SSL_has_pending() to use it. This actually fixes a bug in
SSL_has_pending() which is supposed to return 1 if we have any processed
or unprocessed data sitting in OpenSSL buffers. However it failed to return
1 if we had processed non-application data pending.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2875)
We do not allow the generation of TLSv1.3 cookies. But if we receive one
in an HRR we will echo it back in the ClientHello.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2839)
Change the early data API so that the server must use
SSL_write_early_data() to write to an unauthenticated client.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2737)
This is for consistency with the rest of the API where all the functions
are called *early_data*.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2737)
This is for consistency with the rest of the API where all the functions
are called *early_data*.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2737)
We provide SSL_write_early() which *must* be called first on a connection
(prior to any other IO function including SSL_connect()/SSL_do_handshake()).
Also SSL_write_early_finish() which signals the end of early data.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2737)
This removes the fips configure option. This option is broken as the
required FIPS code is not available.
FIPS_mode() and FIPS_mode_set() are retained for compatibility, but
FIPS_mode() always returns 0, and FIPS_mode_set() can only be used to
turn FIPS mode off.
Reviewed-by: Stephen Henson <steve@openssl.org>
There are a small number of functions in libssl that are internal only
and never used by anything.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2770)
Provide a callback interface that gives the application the ability
to adjust the nascent SSL object at the earliest stage of ClientHello
processing, immediately after extensions have been collected but
before they have been processed.
This is akin to BoringSSL's "select_certificate_cb" (though it is not
API compatible), and as the name indicates, one major use is to examine
the supplied server name indication and select what certificate to
present to the client. However, it can also be used to make more
sweeping configuration changes to the SSL object according to the
selected server identity and configuration. That may include adjusting
the permitted TLS versions, swapping out the SSL_CTX object (as is
traditionally done in a tlsext_servername_callback), changing the
server's cipher list, and more.
We also wish to allow an early callback to indicate that it needs to perform
additional work asynchronously and resume processing later. To that effect,
refactor the second half of tls_process_client_hello() into a subroutine to be
called at the post-processing stage (including the early callback itself), to
allow the callback to result in remaining in the same work stage for a later
call to succeed. This requires allocating for and storing the CLIENTHELLO_MSG
in the SSL object to be preserved across such calls, but the storage is
reclaimed after ClientHello processing finishes.
Information about the CliehtHello is available to the callback by means of
accessor functions that can only be used from the early callback. This allows
extensions to make use of the existing internal parsing machinery without
exposing structure internals (e.g., of PACKET), so that applications do not
have to write fragile parsing code.
Applications are encouraged to utilize an early callback and not use
a servername_callback, in order to avoid unexpected behavior that
occurs due to the relative order of processing between things like
session resumption and the historical servername callback.
Also tidy up nearby style by removing unnecessary braces around one-line
conditional bodies.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2279)
Split off the portions that mutate the SSL object into a separate
function that the state machine calls, so that the public API can
be a pure function. (It still needs the SSL parameter in order
to determine what SSL_METHOD's get_cipher_by_char() routine to use,
though.)
Instead of returning the stack of ciphers (functionality that was
not used internally), require using the output parameter, and add
a separate output parameter for the SCSVs contained in the supplied
octets, if desired. This lets us move to the standard return value
convention. Also make both output stacks optional parameters.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2279)
Move ssl_bytes_to_cipher_list() to ssl_lib.c and create a public
wrapper around it. This lets application early callbacks easily get
SSL_CIPHER objects from the raw ciphers bytes without having to
reimplement the parsing code. In particular, they do not need to
know the details of the sslv2 format ClientHello's ciphersuite
specifications.
Document the new public function, including the arguably buggy behavior
of modifying the supplied SSL object. On the face of it, such a function
should be able to be pure, just a direct translation of wire octets to
internal data structures.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2279)
We use an int instead. That means SSL_key_update() also should use an int.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2609)
Now the certificate and signature algorithm is set in one place we
can use it directly insetad of recalculating it. The old functions
ssl_get_server_send_pkey() and ssl_get_server_cert_index() are no
longer required.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2623)
Add inline function ssl_has_cert which checks to see if a certificate and
private key for a given index are not NULL.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2623)
The original intent of SSL_PKEY_RSA_SIGN and SSL_PKEY_RSA_ENC was to
support two different keys for RSA signing and decrypt. However this
was never implemented and we only ever set one key and the other was
always NULL. Replace with single SSL_PKEY_RSA type.
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2587)
While it's always safe to read |SSL_MAX_SSL_SESSION_ID_LENGTH| bytes
from an |SSL_SESSION|'s |session_id| array, the hash function would do
so with without considering if all those bytes had been written to.
This change checks |session_id_length| before possibly reading
uninitialised memory. Since the result of the hash function was already
attacker controlled, and since a lookup of a short session ID will
always fail, it doesn't appear that this is anything more than a clean
up.
In particular, |ssl_get_prev_session| uses a stack-allocated placeholder
|SSL_SESSION| as a lookup key, so the |session_id| array may be
uninitialised.
This was originally found with libFuzzer and MSan in
https://boringssl.googlesource.com/boringssl/+/e976e4349d693b4bbb97e1694f45be5a1b22c8c7,
then by Robert Swiecki with honggfuzz and MSan here. Thanks to both.
Reviewed-by: Geoff Thorpe <geoff@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2583)
session_ctx and initial_ctx are aliases of each other, and with the
opaque data structures, there's no need to keep both around. Since
there were more references of session_ctx, replace all instances of
initial_ctx with session_ctx.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2334)
The record layer was making decisions that should really be left to the
state machine around unexpected handshake messages that are received after
the initial handshake (i.e. renegotiation related messages). This commit
removes that code from the record layer and updates the state machine
accordingly. This simplifies the state machine and paves the way for
handling other messages post-handshake such as the NewSessionTicket in
TLSv1.3.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2259)
The existing code used the magic number -1 to represent the absence of
a status_type in the extension. This commit replaces it with a macro.
Perl changes reviewed by Richard Levitte. Non-perl changes reviewed by Rich
Salz
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
This is a skin deep change, which simply renames most places where we talk
about curves in a TLS context to groups. This is because TLS1.3 has renamed
the extension, and it can now include DH groups too. We still only support
curves, but this rename should pave the way for a future extension for DH
groups.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Travis is reporting one file at a time shadowed variable warnings where
"read" has been used. This attempts to go through all of libssl and replace
"read" with "readbytes" to fix all the problems in one go.
Reviewed-by: Rich Salz <rsalz@openssl.org>
We also modify the SSL_get_error() function to handle the fact that with
SSL_write_ex() the error return is 0 not -1, and fix some bugs in the
SSL BIO reading.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Includes addition of the various options to s_server/s_client. Also adds
one of the new TLS1.3 ciphersuites.
This isn't "real" TLS1.3!! It's identical to TLS1.2 apart from the protocol
and the ciphersuite...and the ciphersuite is just a renamed TLS1.2 one (not
a "real" TLS1.3 ciphersuite).
Reviewed-by: Rich Salz <rsalz@openssl.org>
For convenience, combine getting a new ref for the new SSL_CTX
with assigning the store and freeing the old one.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1755)
Run util/openssl-format-source on ssl/
Some comments and hand-formatted tables were fixed up
manually by disabling auto-formatting.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Commit d8e8590e ("Fix missing return value checks in SCTP") made the
DTLS handshake fail, even for non-SCTP connections, if
SSL_export_keying_material() fails. Which it does, for DTLS1_BAD_VER.
Apply the trivial fix to make it succeed, since there's no real reason
why it shouldn't even though we never need it.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
SSL_set_rbio() and SSL_set_wbio() are new functions in 1.1.0 and really
should be called SSL_set0_rbio() and SSL_set0_wbio(). The old
implementation was not consistent with what "set0" means though as there
were special cases around what happens if the rbio and wbio are the same.
We were only ever taking one reference on the BIO, and checking everywhere
whether the rbio and wbio are the same so as not to double free.
A better approach is to rename the functions to SSL_set0_rbio() and
SSL_set0_wbio(). If an existing BIO is present it is *always* freed
regardless of whether the rbio and wbio are the same or not. It is
therefore the callers responsibility to ensure that a reference is taken
for *each* usage, i.e. one for the rbio and one for the wbio.
The legacy function SSL_set_bio() takes both the rbio and wbio in one go
and sets them both. We can wrap up the old behaviour in the implementation
of that function, i.e. previously if the rbio and wbio are the same in the
call to this function then the caller only needed to ensure one reference
was passed. This behaviour is retained by internally upping the ref count.
This commit was inspired by BoringSSL commit f715c423224.
RT#4572
Reviewed-by: Rich Salz <rsalz@openssl.org>
When setting the read bio we free up any old existing one. However this can
lead to a double free if the existing one is the same as the write bio.
Reviewed-by: Rich Salz <rsalz@openssl.org>
This is adapted from BoringSSL commit 2f87112b963.
This fixes a number of bugs where the existence of bbio was leaked in the
public API and broke things.
- SSL_get_wbio returned the bbio during the handshake. It must always return
the BIO the consumer configured. In doing so, some internal accesses of
SSL_get_wbio should be switched to ssl->wbio since those want to see bbio.
- The logic in SSL_set_rfd, etc. (which I doubt is quite right since
SSL_set_bio's lifetime is unclear) would get confused once wbio got
wrapped. Those want to compare to SSL_get_wbio.
- If SSL_set_bio was called mid-handshake, bbio would get disconnected and
lose state. It forgets to reattach the bbio afterwards. Unfortunately,
Conscrypt does this a lot. It just never ended up calling it at a point
where the bbio would cause problems.
- Make more explicit the invariant that any bbio's which exist are always
attached. Simplify a few things as part of that.
RT#4572
Reviewed-by: Richard Levitte <levitte@openssl.org>
Fix some indentation at the same time
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1292)
In light of potential UKS (unknown key share) attacks on some
applications, primarily browsers, despite RFC761, name checks are
by default applied with DANE-EE(3) TLSA records. Applications for
which UKS is not a problem can optionally disable DANE-EE(3) name
checks via the new SSL_CTX_dane_set_flags() and friends.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Sessions are stored on the session_ctx, which doesn't change after
SSL_set_SSL_CTX().
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
The write BIO for handshake messages is bufferred so that we only write
out to the network when we have a complete flight. There was some
complexity in the buffering logic so that we switched buffering on and
off at various points through out the handshake. The only real reason to
do this was historically it complicated the state machine when you wanted
to flush because you had to traverse through the "flush" state (in order
to cope with NBIO). Where we knew up front that there was only going to
be one message in the flight we switched off buffering to avoid that.
In the new state machine there is no longer a need for a flush state so
it is simpler just to have buffering on for the whole handshake. This
also gives us the added benefit that we can simply call flush after every
flight even if it only has one message in it. This means that BIO authors
can implement their own buffering strategies and not have to be aware of
the state of the SSL object (previously they would have to switch off
their own buffering during the handshake because they could not rely on
a flush being received when they really needed to write data out). This
last point addresses GitHub Issue #322.
Reviewed-by: Andy Polyakov <appro@openssl.org>
Since with SSL_VERIFY_NONE, the connection may continue and the
session may even be cached, we should save some evidence that the
chain was not sufficiently verified and would have been rejected
with SSL_VERIFY_PEER. To that end when a CT callback returs failure
we set the verify result to X509_V_ERR_NO_VALID_SCTS.
Note: We only run the CT callback in the first place if the verify
result is still X509_V_OK prior to start of the callback.
RT #4502
Reviewed-by: Tim Hudson <tjh@openssl.org>
Add a status return value instead of void.
Add some sanity checks on reference counter value.
Update the docs.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
If the application has limited the size of the async pool using
ASYNC_init_thread() then we could run out of jobs while trying to start a
libssl io operation. However libssl was failing to handle this and treating
it like a fatal error. It should not be fatal...we just need to retry when
there are jobs available again.
Reviewed-by: Richard Levitte <levitte@openssl.org>
It is up to the caller of SSL_dane_tlsa_add() to take appropriate
action when no records are added successfully or adding some records
triggers an internal error (negative return value).
With this change the caller can continue with PKIX if desired when
none of the TLSA records are usable, or take some appropriate action
if DANE is required.
Also fixed the internal ssl_dane_dup() function to properly initialize
the TLSA RR stack in the target SSL handle. Errors in ssl_dane_dup()
are no longer ignored.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Add an accessor for SSL_CTX.
Since libssl was made opaque, there is no way for users to access the
cipher_list, while users can set the cipher_list by
SSL_CTX_set_cipher_list().
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
Since NDEBUG is defined unconditionally on command line for release
builds, we can omit *_DEBUG options in favour of effective "all-on"
in debug builds exercised though CI.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Suppress CT callbacks with aNULL or PSK ciphersuites that involve
no certificates. Ditto when the certificate chain is validated via
DANE-TA(2) or DANE-EE(3) TLSA records. Also skip SCT processing
when the chain is fails verification.
Move and consolidate CT callbacks from libcrypto to libssl. We
also simplify the interface to SSL_{,CTX_}_enable_ct() which can
specify either a permissive mode that just collects information or
a strict mode that requires at least one valid SCT or else asks to
abort the connection.
Simplified SCT processing and options in s_client(1) which now has
just a simple pair of "-noct" vs. "-ct" options, the latter enables
the permissive callback so that we can complete the handshake and
report all relevant information. When printing SCTs, print the
validation status if set and not valid.
Signed-off-by: Rob Percival <robpercival@google.com>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Move the the BIO_METHOD and BIO structures into internal header files,
provide appropriate accessor methods and update all internal code to use
the new accessors where appropriate.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Don't have #error statements in header files, but instead wrap
the contents of that file in #ifndef OPENSSL_NO_xxx
This means it is now always safe to include the header file.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Remove 'log' field from SCT and related accessors
In order to still have access to an SCT's CTLOG when calling SCT_print,
SSL_CTX_get0_ctlog_store has been added.
Improved documentation for some CT functions in openssl/ssl.h.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
* Perform ALPN after the SNI callback; the SSL_CTX may change due to
that processing
* Add flags to indicate that we actually sent ALPN, to properly error
out if unexpectedly received.
* clean up ssl3_free() no need to explicitly clear when doing memset
* document ALPN functions
Signed-off-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
This is similar to SSL_pending() but just returns a 1 if there is data
pending in the internal OpenSSL buffers or 0 otherwise (as opposed to
SSL_pending() which returns the number of bytes available). Unlike
SSL_pending() this will work even if "read_ahead" is set (which is the
case if you are using read pipelining, or if you are doing DTLS). A 1
return value means that we have unprocessed data. It does *not* necessarily
indicate that there will be application data returned from a call to
SSL_read(). The unprocessed data may not be application data or there
could be errors when we attempt to parse the records.
Reviewed-by: Tim Hudson <tjh@openssl.org>
This capability is required for read pipelining. We will only read in as
many records as will fit in the read buffer (and the network can provide
in one go). The bigger the buffer the more records we can process in
parallel.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Read pipelining is controlled in a slightly different way than with write
pipelining. While reading we are constrained by the number of records that
the peer (and the network) can provide to us in one go. The more records
we can get in one go the more opportunity we have to parallelise the
processing.
There are two parameters that affect this:
* The number of pipelines that we are willing to process in one go. This is
controlled by max_pipelines (as for write pipelining)
* The size of our read buffer. A subsequent commit will provide an API for
adjusting the size of the buffer.
Another requirement for this to work is that "read_ahead" must be set. The
read_ahead parameter will attempt to read as much data into our read buffer
as the network can provide. Without this set, data is read into the read
buffer on demand. Setting the max_pipelines parameter to a value greater
than 1 will automatically also turn read_ahead on.
Finally, the read pipelining as currently implemented will only parallelise
the processing of application data records. This would only make a
difference for renegotiation so is unlikely to have a significant impact.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Use the new pipeline cipher capability to encrypt multiple records being
written out all in one go. Two new SSL/SSL_CTX parameters can be used to
control how this works: max_pipelines and split_send_fragment.
max_pipelines defines the maximum number of pipelines that can ever be used
in one go for a single connection. It must always be less than or equal to
SSL_MAX_PIPELINES (currently defined to be 32). By default only one
pipeline will be used (i.e. normal non-parallel operation).
split_send_fragment defines how data is split up into pipelines. The number
of pipelines used will be determined by the amount of data provided to the
SSL_write call divided by split_send_fragment. For example if
split_send_fragment is set to 2000 and max_pipelines is 4 then:
SSL_write called with 0-2000 bytes == 1 pipeline used
SSL_write called with 2001-4000 bytes == 2 pipelines used
SSL_write called with 4001-6000 bytes == 3 pipelines used
SSL_write_called with 6001+ bytes == 4 pipelines used
split_send_fragment must always be less than or equal to max_send_fragment.
By default it is set to be equal to max_send_fragment. This will mean that
the same number of records will always be created as would have been
created in the non-parallel case, although the data will be apportioned
differently. In the parallel case data will be spread equally between the
pipelines.
Reviewed-by: Tim Hudson <tjh@openssl.org>
