Add new flag TLS1_FLAGS_RECEIVED_EXTMS which is set when the peer sends
the extended master secret extension.
Server now sends extms if and only if the client sent extms.
Check consistency of extms extension when resuming sessions following (where
practical) RFC7627.
Reviewed-by: Matt Caswell <matt@openssl.org>
SSL_{CTX}_set_tmp_ecdh() allows to set 1 EC curve and then tries to use it. On
the other hand SSL_{CTX_}set1_curves() allows you to set a list of curves, but
only when SSL_{CTX_}set_ecdh_auto() was called to turn it on.
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
This only gets used to set a specific curve without actually checking that the
peer supports it or not and can therefor result in handshake failures that can
be avoided by selecting a different cipher.
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
Don't hard code EVP_sha* etc for signature algorithms: use table
indices instead. Add SHA224 and SHA512 to tables.
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Change handshake hash array into a single digest context simplifying the
handhake hash code. Use EVP_md5_sha1() if needed for handshake hashes in
TLS 1.1 and earlier.
Simplify PRF code to also use a single digest and treat EVP_md5_sha1()
as a special case.
Modify algorithm2 field of ciphers to use a single index value for handshake
hash and PRF instead of a bitmap.
Reviewed-by: Matt Caswell <matt@openssl.org>
This patch contains the necessary changes to provide GOST 2012
ciphersuites in TLS. It requires the use of an external GOST 2012 engine.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
The following entry points have been made async aware:
SSL_accept
SSL_read
SSL_write
Also added is a new mode - SSL_MODE_ASYNC. Calling the above functions with
the async mode enabled will initiate a new async job. If an async pause is
encountered whilst executing the job (such as for example if using SHA1/RSA
with the Dummy Async engine), then the above functions return with
SSL_WANT_ASYNC. Calling the functions again (with exactly the same args
as per non-blocking IO), will resume the job where it left off.
Reviewed-by: Rich Salz <rsalz@openssl.org>
There are lots of calls to EVP functions from within libssl There were
various places where we should probably check the return value but don't.
This adds these checks.
Reviewed-by: Richard Levitte <levitte@openssl.org>
This disables some ciphersuites which aren't supported in SSL v3:
specifically PSK ciphersuites which use SHA256 or SHA384 for the MAC.
Thanks to the Open Crypto Audit Project for identifying this issue.
Reviewed-by: Matt Caswell <matt@openssl.org>
The new function SSL_use_certificate_chain_file was always crashing in
the internal function use_certificate_chain_file because it would pass a
NULL value for SSL_CTX *, but use_certificate_chain_file would
unconditionally try to dereference it.
Reviewed-by: Stephen Henson <steve@openssl.org>
There were a few remaining references to SSLv2 support which are no longer
relevant now that it has been removed.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
The function dtls1_link_min_mtu() was only used within d1_lib.c so make
it static.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
The SSL variable |in_handshake| seems misplaced. It would be better to have
it in the STATEM structure.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
The |no_cert_verify| should be in the state machine structure not in SSL
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
The next_state variable is no longer needed in the new state machine.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Move some function definitions around within the state machine to make sure
they are in the correct files. Also create a statem_locl.h header for stuff
entirely local to the state machine code and move various definitions into
it.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Pull out the state machine into a separate sub directory. Also moved some
functions which were nothing to do with the state machine but were in state
machine files. Pulled all the SSL_METHOD definitions into one place...most
of those files had very little left in them any more.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
ssl_get_message is no longer used so it should be removed from
ssl_method_st
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Previously each message specific process function would create its own
PACKET structure. Rather than duplicate all of this code lots of times we
should create it in the state machine itself.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
The SSL structure contained a "state" variable that kept track of the state
machine in the old code. The new state machine does not use this so it can
be removed.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
The SSL structure contained a "type" variable that was set to either
SSL_ST_ACCEPT or SSL_ST_CONNECT depending on whether we are the server or
the client. This duplicates the capability of the "server" variable and was
actually rarely used.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Clean up and remove lots of code that is now no longer needed due to the
move to the new state machine.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Implement all of the necessary changes to make DTLS on the server work
with the new state machine code.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Split the TLS server ssl3_get_* and ssl3_send_* functions into two ready
for the migration to the new state machine code.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Remove all the functions and dead code that is now no longer required as
a result of the DTLS client move into the new state machine code.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Move all DTLS client side processing into the new state machine code. A
subsequent commit will clean up the old dead code.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Create a dtls_get_message function similar to the old dtls1_get_message but
in the format required for the new state machine code. The old function will
eventually be deleted in later commits.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
This swaps the implementation of the client TLS state machine to use the
new state machine code instead.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
The new state machine code will split up the reading and writing of
hanshake messages into discrete phases. In order to facilitate that the
existing "get" type functions will be split into two halves: one to get
the message and one to process it. The "send" type functions will also have
all work relating to constructing the message split out into a separate
function just for that. For some functions there will also be separate
pre and post "work" phases to prepare or update state.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
This is the first drop of the new state machine code.
The rewrite has the following objectives:
- Remove duplication of state code between client and server
- Remove duplication of state code between TLS and DTLS
- Simplify transitions and bring the logic together in a single location
so that it is easier to validate
- Remove duplication of code between each of the message handling functions
- Receive a message first and then work out whether that is a valid
transition - not the other way around (the other way causes lots of issues
where we are expecting one type of message next but actually get something
else)
- Separate message flow state from handshake state (in order to better
understand each)
- message flow state = when to flush buffers; handling restarts in the
event of NBIO events; handling the common flow of steps for reading a
message and the common flow of steps for writing a message etc
- handshake state = what handshake message are we working on now
- Control complexity: only the state machine can change state: keep all
the state changes local to a file
This builds on previous state machine related work:
- Surface CCS processing in the state machine
- Version negotiation rewrite
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
The function ssl3_get_message gets a whole message from the underlying bio
and returns it to the state machine code. The new state machine code will
split this into two discrete steps: get the message header and get the
message body. This commit splits the existing function into these two
sub steps to facilitate the state machine implementation.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Note that this commit constifies a user callback parameter and therefore
will break compilation for applications using this callback. But unless
they are abusing write access to the buffer, the fix is trivial.
Reviewed-by: Andy Polyakov <appro@openssl.org>
Move all packet parsing to the beginning of the method. This limits the
SSLv2 compatibility soup to the parsing, and makes the rest of the
processing uniform.
This is also needed for simpler EMS support: EMS servers need to do an
early scan for EMS to make resumption decisions. This'll be easier when
the entire ClientHello is parsed in the beginning.
As a side effect,
1) PACKETize ssl_get_prev_session and tls1_process_ticket; and
2) Delete dead code for SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG.
Reviewed-by: Matt Caswell <matt@openssl.org>
This patch updates the "DEFAULT" cipherstring to be
"ALL:!COMPLEMENTOFDEFAULT:!eNULL". COMPLEMENTOFDEFAULT is now defined
internally by a flag on each ciphersuite indicating whether it should be
excluded from DEFAULT or not. This gives us control at an individual
ciphersuite level as to exactly what is in DEFAULT and what is not.
Finally all DES, RC4 and RC2 ciphersuites are added to COMPLEMENTOFDEFAULT
and hence removed from DEFAULT.
Reviewed-by: Tim Hudson <tjh@openssl.org>
The old implementation of DTLSv1_listen which has now been replaced still
had a few vestiges scattered throughout the code. This commit removes them.
Reviewed-by: Andy Polyakov <appro@openssl.org>
The existing implementation of DTLSv1_listen() is fundamentally flawed. This
function is used in DTLS solutions to listen for new incoming connections
from DTLS clients. A client will send an initial ClientHello. The server
will respond with a HelloVerifyRequest containing a unique cookie. The
client the responds with a second ClientHello - which this time contains the
cookie.
Once the cookie has been verified then DTLSv1_listen() returns to user code,
which is typically expected to continue the handshake with a call to (for
example) SSL_accept().
Whilst listening for incoming ClientHellos, the underlying BIO is usually in
an unconnected state. Therefore ClientHellos can come in from *any* peer.
The arrival of the first ClientHello without the cookie, and the second one
with it, could be interspersed with other intervening messages from
different clients.
The whole purpose of this mechanism is as a defence against DoS attacks. The
idea is to avoid allocating state on the server until the client has
verified that it is capable of receiving messages at the address it claims
to come from. However the existing DTLSv1_listen() implementation completely
fails to do this. It attempts to super-impose itself on the standard state
machine and reuses all of this code. However the standard state machine
expects to operate in a stateful manner with a single client, and this can
cause various problems.
A second more minor issue is that the return codes from this function are
quite confused, with no distinction made between fatal and non-fatal errors.
Most user code treats all errors as non-fatal, and simply retries the call
to DTLSv1_listen().
This commit completely rewrites the implementation of DTLSv1_listen() and
provides a stand alone implementation that does not rely on the existing
state machine. It also provides more consistent return codes.
Reviewed-by: Andy Polyakov <appro@openssl.org>
Since SSLv3, a CipherSuite is always 2 bytes. The only place where we
need 3-byte ciphers is SSLv2-compatible ClientHello processing.
So, remove the ssl_put_cipher_by_char indirection.
Reviewed-by: Rich Salz <rsalz@openssl.org>
For server use a PSK identity hint value in the CERT structure which
is inherited when SSL_new is called and which allows applications to
set hints on a per-SSL basis. The previous version of
SSL_use_psk_identity_hint tried (wrongly) to use the SSL_SESSION structure.
PR#4039
Reviewed-by: Matt Caswell <matt@openssl.org>
This was obsolete in 2001. This is not the same as Gost94 digest.
Thanks to Dmitry Belyavsky <beldmit@gmail.com> for review and advice.
Reviewed-by: Matt Caswell <matt@openssl.org>
Continuing on from the previous commit this moves the processing of DTLS
CCS messages out of the record layer and into the state machine.
Reviewed-by: Tim Hudson <tjh@openssl.org>
The handling of incoming CCS records is a little strange. Since CCS is not
a handshake message it is handled differently to normal handshake messages.
Unfortunately whilst technically it is not a handhshake message the reality
is that it must be processed in accordance with the state of the handshake.
Currently CCS records are processed entirely within the record layer. In
order to ensure that it is handled in accordance with the handshake state
a flag is used to indicate that it is an acceptable time to receive a CCS.
Previously this flag did not exist (see CVE-2014-0224), but the flag should
only really be considered a workaround for the problem that CCS is not
visible to the state machine.
Outgoing CCS messages are already handled within the state machine.
This patch makes CCS visible to the TLS state machine. A separate commit
will handle DTLS.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Provide more robust (inline) functions to replace n2s, n2l, etc. These
functions do the same thing as the previous macros, but also keep track
of the amount of data remaining and return an error if we try to read more
data than we've got.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Add support for RSAPSK, DHEPSK and ECDHEPSK server side.
Update various checks to ensure certificate and server key exchange messages
are only sent when required.
Update message handling. PSK server key exchange parsing now include an
identity hint prefix for all PSK server key exchange messages. PSK
client key exchange message expects PSK identity and requests key for
all PSK key exchange ciphersuites.
Update flags for RSA, DH and ECDH so they are also used in PSK.
Reviewed-by: Matt Caswell <matt@openssl.org>
This flag was not set anywhere within the codebase (only read). It could
only be set by an app reaching directly into s->s3->flags and setting it
directly. However that method became impossible when libssl was opaquified.
Even in 1.0.2/1.0.1 if an app set the flag directly it is only relevant to
ssl3_connect(), which calls SSL_clear() during initialisation that clears
any flag settings. Therefore it could take effect if the app set the flag
after the handshake has started but before it completed. It seems quite
unlikely that any apps really do this (especially as it is completely
undocumented).
The purpose of the flag is suppress flushing of the write bio on the client
side at the end of the handshake after the client has written the Finished
message whilst resuming a session. This enables the client to send
application data as part of the same flight as the Finished message.
This flag also controls the setting of a second flag SSL3_FLAGS_POP_BUFFER.
There is an interesting comment in the code about this second flag in the
implementation of ssl3_write:
/* This is an experimental flag that sends the
* last handshake message in the same packet as the first
* use data - used to see if it helps the TCP protocol during
* session-id reuse */
It seems the experiment did not work because as far as I can tell nothing
is using this code. The above comment has been in the code since SSLeay.
This commit removes support for SSL3_FLAGS_DELAY_CLIENT_FINISHED, as well
as the associated SSL3_FLAGS_POP_BUFFER.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Rewrite ssl3_digest_cached_records handling. Only digest cached records
if digest array is NULL: this means it is safe to call
ssl3_digest_cached_records multiple times (subsequent calls are no op).
Remove flag TLS1_FLAGS_KEEP_HANDSHAKE instead only update handshake buffer
if digest array is NULL.
Add additional "keep" parameter to ssl3_digest_cached_records to indicate
if the handshake buffer should be retained after digesting cached records
(needed for TLS 1.2 client authentication).
Reviewed-by: Matt Caswell <matt@openssl.org>
As numerous comments indicate the certificate and key array is not an
appopriate structure to store the peers certificate: so remove it and
just the s->session->peer instead.
Reviewed-by: Richard Levitte <levitte@openssl.org>
If a NewSessionTicket is received by a multi-threaded client when
attempting to reuse a previous ticket then a race condition can occur
potentially leading to a double free of the ticket data.
CVE-2015-1791
This also fixes RT#3808 where a session ID is changed for a session already
in the client session cache. Since the session ID is the key to the cache
this breaks the cache access.
Parts of this patch were inspired by this Akamai change:
c0bf69a791
Reviewed-by: Rich Salz <rsalz@openssl.org>
Given the pervasive nature of TLS extensions it is inadvisable to run
OpenSSL without support for them. It also means that maintaining
the OPENSSL_NO_TLSEXT option within the code is very invasive (and probably
not well tested). Therefore it is being removed.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Move per-connection state out of the CERT structure: which should just be
for shared configuration data (e.g. certificates to use).
In particular move temporary premaster secret, raw ciphers, peer signature
algorithms and shared signature algorithms.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Following the version negotiation rewrite all of the previous code that was
dedicated to version negotiation can now be deleted - all six source files
of it!!
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
This commit changes the way that we do server side protocol version
negotiation. Previously we had a whole set of code that had an "up front"
state machine dedicated to the negotiating the protocol version. This adds
significant complexity to the state machine. Historically the justification
for doing this was the support of SSLv2 which works quite differently to
SSLv3+. However, we have now removed support for SSLv2 so there is little
reason to maintain this complexity.
The one slight difficulty is that, although we no longer support SSLv2, we
do still support an SSLv3+ ClientHello in an SSLv2 backward compatible
ClientHello format. This is generally only used by legacy clients. This
commit adds support within the SSLv3 code for these legacy format
ClientHellos.
Server side version negotiation now works in much the same was as DTLS,
i.e. we introduce the concept of TLS_ANY_VERSION. If s->version is set to
that then when a ClientHello is received it will work out the most
appropriate version to respond with. Also, SSLv23_method and
SSLv23_server_method have been replaced with TLS_method and
TLS_server_method respectively. The old SSLv23* names still exist as
macros pointing at the new name, although they are deprecated.
Subsequent commits will look at client side version negotiation, as well of
removal of the old s23* code.
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
Remove RFC2712 Kerberos support from libssl. This code and the associated
standard is no longer considered fit-for-purpose.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Since COMP_METHOD is now defined in comp_lcl.h, it is no
longer possible to create new TLS compression methods without
using the OpenSSL source. Only ZLIB is supported by default.
Also, since the types are opaque, #ifdef guards to use "char *"
instead of the real type aren't necessary.
The changes are actually minor. Adding missing copyright to some
files makes the diff misleadingly big.
Reviewed-by: Matt Caswell <matt@openssl.org>
The return value is checked for 0. This is currently safe but we should
really check for <= 0 since -1 is frequently used for error conditions.
Thanks to Kevin Wojtysiak (Int3 Solutions) and Paramjot Oberoi (Int3
Solutions) for reporting this issue.
Reviewed-by: Andy Polyakov <appro@openssl.org>
Also push some usage of last_write_sequence out of dtls1_retransmit_message
and into the record layer.
Reviewed-by: Richard Levitte <levitte@openssl.org>
The recent updates to libssl to enforce stricter return code checking, left
a small number of instances behind where return codes were being swallowed
(typically because the function they were being called from was declared as
void). This commit fixes those instances to handle the return codes more
appropriately.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Change ssl_set_handshake_header from return void to returning int, and
handle error return code appropriately.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Mark most functions returning a result defined in any libssl header file
with __owur to warn if they are used without checking the return value.
Use -DUNUSED_RETURN compiler flag with gcc to activate these warnings.
Some functions returning a result are skipped if it is common and valid to
use these functions without checking the return value.
Reviewed-by: Richard Levitte <levitte@openssl.org>
It created the cert structure in SSL_CTX or SSL if it was NULL, but they can
never be NULL as the comments already said.
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
From RFC4507:
"The ticket_lifetime_hint field contains a hint from the server about how
long the ticket should be stored. The value indicates the lifetime in
seconds as a 32-bit unsigned integer in network byte order."
Reviewed-by: Tim Hudson <tjh@openssl.org>
Rewrite ssl3_send_client_key_exchange to retain the premaster secret
instead of using it immediately.
This is needed because the premaster secret is used after the client key
exchange message has been sent to compute the extended master secret.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Retrieve handshake hashes in a separate function. This tidies the existing
code and will be used for extended master secret generation.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Add a "flags" field to SSL_SESSION. This will contain various flags
such as encrypt-then-mac and extended master secret support.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Remove OPENSSL_NO_BUF_FREELISTS. This was turned on by default,
so the work here is removing the 'maintain our own freelist' code.
Also removed a minor old Windows-multibyte/widechar conversion flag.
Reviewed-by: Andy Polyakov <appro@openssl.org>
Remove support for SHA0 and DSS0 (they were broken), and remove
the ability to attempt to build without SHA (it didn't work).
For simplicity, remove the option of not building various SHA algorithms;
you could argue that SHA_224/256/384/512 should be kept, since they're
like crypto algorithms, but I decided to go the other way.
So these options are gone:
GENUINE_DSA OPENSSL_NO_SHA0
OPENSSL_NO_SHA OPENSSL_NO_SHA1
OPENSSL_NO_SHA224 OPENSSL_NO_SHA256
OPENSSL_NO_SHA384 OPENSSL_NO_SHA512
Reviewed-by: Richard Levitte <levitte@openssl.org>
Sometimes it fails to format them very well, and sometimes it corrupts them!
This commit moves some particularly problematic ones.
Reviewed-by: Tim Hudson <tjh@openssl.org>
MS Server gated cryptography is obsolete and dates from the time of export
restrictions on strong encryption and is only used by ancient versions of
MSIE.
Reviewed-by: Matt Caswell <matt@openssl.org>
and instead use the value provided by the underlying BIO. Also provide some
new DTLS_CTRLs so that the library user can set the mtu without needing to
know this constant. These new DTLS_CTRLs provide the capability to set the
link level mtu to be used (i.e. including this IP/UDP overhead). The previous
DTLS_CTRLs required the library user to subtract this overhead first.
Reviewed-by: Tim Hudson <tjh@openssl.org>
The client sends a session ID with the session ticket, and uses
the returned ID to detect resumption, so we do not need to peek
at handshake messages: s->hit tells us explicitly if we're resuming.
An equivalent change was independently made in BoringSSL, see commit
407886f589cf2dbaed82db0a44173036c3bc3317.
Reviewed-by: Matt Caswell <matt@openssl.org>
The supported signature algorithms extension needs to be processed before
the certificate to use is decided and before a cipher is selected (as the
set of shared signature algorithms supported may impact the choice).
Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit 56e8dc542b)
Conflicts:
ssl/ssl.h
ssl/ssl_err.c
Support separate parse and add callback arguments.
Add new callback so an application can free extension data.
Change return value for send functions so < 0 is an error 0
omits extension and > 0 includes it. This is more consistent
with the behaviour of other functions in OpenSSL.
Modify parse_cb handling so <= 0 is an error.
Make SSL_CTX_set_custom_cli_ext and SSL_CTX_set_custom_cli_ext argument
order consistent.
NOTE: these changes WILL break existing code.
Remove (now inaccurate) in line documentation.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Use "parse" and "add" for function and callback names instead of
"first" and "second".
Change arguments to callback so the extension type is unsigned int
and the buffer length is size_t. Note: this *will* break existing code.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Reject attempts to use extensions handled internally.
Add flags to each extension structure to indicate if an extension
has been sent or received. Enforce RFC5246 compliance by rejecting
duplicate extensions and unsolicited extensions and only send a
server extension if we have sent the corresponding client extension.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Use the same structure for client and server custom extensions.
Add utility functions in new file t1_ext.c.
Use new utility functions to handle custom server and client extensions
and remove a lot of code duplication.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Move custom extension structures from SSL_CTX to CERT structure.
This change means the form can be revised in future without binary
compatibility issues. Also since CERT is part of SSL structures
so per-SSL custom extensions could be supported in future as well as
per SSL_CTX.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Don't call internal functions directly call them through
SSL_test_functions(). This also makes unit testing work on
Windows and platforms that don't export internal functions
from shared libraries.
By default unit testing is not enabled: it requires the compile
time option "enable-unit-test".
Reviewed-by: Geoff Thorpe <geoff@openssl.org>
Security callback: selects which parameters are permitted including
sensible defaults based on bits of security.
The "parameters" which can be selected include: ciphersuites,
curves, key sizes, certificate signature algorithms, supported
signature algorithms, DH parameters, SSL/TLS version, session tickets
and compression.
In some cases prohibiting the use of a parameters will mean they are
not advertised to the peer: for example cipher suites and ECC curves.
In other cases it will abort the handshake: e.g DH parameters or the
peer key size.
Documentation to follow...
New function ssl_cipher_disabled.
Check for disabled client ciphers using ssl_cipher_disabled.
New function to return only supported ciphers.
New option to ciphers utility to print only supported ciphers.
Add auto DH parameter support. This is roughly equivalent to the
ECDH auto curve selection but for DH. An application can just call
SSL_CTX_set_auto_dh(ctx, 1);
and appropriate DH parameters will be used based on the size of the
server key.
Unlike ECDH there is no way a peer can indicate the range of DH parameters
it supports. Some peers cannot handle DH keys larger that 1024 bits for
example. In this case if you call:
SSL_CTX_set_auto_dh(ctx, 2);
Only 1024 bit DH parameters will be used.
If the server key is 7680 bits or more in size then 8192 bit DH parameters
will be used: these will be *very* slow.
The old export ciphersuites aren't supported but those are very
insecure anyway.
If multiple TLS extensions are expected but not received, the TLS extension and supplemental data 'generate' callbacks are the only chance for the receive-side to trigger a specific TLS alert during the handshake.
Removed logic which no-op'd TLS extension generate callbacks (as the generate callbacks need to always be called in order to trigger alerts), and updated the serverinfo-specific custom TLS extension callbacks to track which custom TLS extensions were received by the client, where no-ops for 'generate' callbacks are appropriate.
New ctrl sets current certificate based on certain criteria. Currently
two options: set the first valid certificate as current and set the
next valid certificate as current. Using these an application can
iterate over all certificates in an SSL_CTX or SSL structure.
DHE is the standard term used by the RFCs and by other TLS
implementations. It's useful to have the internal variables use the
standard terminology.
This patch leaves a synonym SSL_kEDH in place, though, so that older
code can still be built against it, since that has been the
traditional API. SSL_kEDH should probably be deprecated at some
point, though.
ECDHE is the standard term used by the RFCs and by other TLS
implementations. It's useful to have the internal variables use the
standard terminology.
This patch leaves a synonym SSL_kEECDH in place, though, so that older
code can still be built against it, since that has been the
traditional API. SSL_kEECDH should probably be deprecated at some
point, though.
PR#3169
This patch, which currently applies successfully against master and
1_0_2, adds the following functions:
SSL_[CTX_]select_current_cert() - set the current certificate without
disturbing the existing structure.
SSL_[CTX_]get0_chain_certs() - get the current certificate's chain.
SSL_[CTX_]clear_chain_certs() - clear the current certificate's chain.
The patch also adds these functions to, and fixes some existing errors
in, SSL_CTX_add1_chain_cert.pod.
Instead, send random bytes, unless SSL_SEND_{CLIENT,SERVER}RANDOM_MODE
is set.
This is a forward-port of commits:
4af793036ff4c93b46ed3da721dac92583270191
While the gmt_unix_time record was added in an ostensible attempt to
mitigate the dangers of a bad RNG, its presence leaks the host's view
of the current time in the clear. This minor leak can help
fingerprint TLS instances across networks and protocols... and what's
worse, it's doubtful thet the gmt_unix_time record does any good at
all for its intended purpose, since:
* It's quite possible to open two TLS connections in one second.
* If the PRNG output is prone to repeat itself, ephemeral
handshakes (and who knows what else besides) are broken.
Experimental support for encrypt then mac from
draft-gutmann-tls-encrypt-then-mac-02.txt
To enable it set the appropriate extension number (0x10 for the test server)
using e.g. -DTLSEXT_TYPE_encrypt_then_mac=0x10
For non-compliant peers (i.e. just about everything) this should have no
effect.
Removed prior audit proof logic - audit proof support was implemented using the generic TLS extension API
Tests exercising the new supplemental data registration and callback api can be found in ssltest.c.
Implemented changes to s_server and s_client to exercise supplemental data callbacks via the -auth argument, as well as additional flags to exercise supplemental data being sent only during renegotiation.
Check for Suite B support using method flags instead of version numbers:
anything supporting TLS 1.2 cipher suites will also support Suite B.
Return an error if an attempt to use DTLS 1.0 is made in Suite B mode.
Since s->method does not reflect the final client version when a client
hello is sent for SSLv23_client_method it can't be relied on to indicate
if TLS 1.2 ciphers should be used. So use the client version instead.
Add correct flags for DTLS 1.2, update s_server and s_client to handle
DTLS 1.2 methods.
Currently no support for version negotiation: i.e. if client/server selects
DTLS 1.2 it is that or nothing.
Use the enc_flags field to determine whether we should use explicit IV,
signature algorithms or SHA256 default PRF instead of hard coding which
versions support each requirement.
Revise DTLS code. There was a *lot* of code duplication in the
DTLS code that generates records. This makes it harder to maintain and
sometimes a TLS update is omitted by accident from the DTLS code.
Specifically almost all of the record generation functions have code like
this:
some_pointer = buffer + HANDSHAKE_HEADER_LENGTH;
... Record creation stuff ...
set_handshake_header(ssl, SSL_MT_SOMETHING, message_len);
...
write_handshake_message(ssl);
Where the "Record creation stuff" is identical between SSL/TLS and DTLS or
in some cases has very minor differences.
By adding a few fields to SSL3_ENC to include the header length, some flags
and function pointers for handshake header setting and handshake writing the
code can cope with both cases.
Note: although this passes "make test" and some simple DTLS tests there may
be some minor differences in the DTLS code that have to be accounted for.
Add DTLS record header parsing, different client hello format and add
HelloVerifyRequest message type.
Add code to d1_pkt.c to send message headers to the message callback.
Kludge alert. This is arranged by passing padding length in unused
bits of SSL3_RECORD->type, so that orig_len can be reconstructed.
(cherry picked from commit 8bfd4c659f)
We have to use EVP in FIPS mode so we can only partially mitigate
timing differences.
Make an extra call to EVP_DigestSignUpdate to hash additonal blocks
to cover any timing differences caused by removal of padding.
(cherry picked from commit b908e88ec1)
This patch makes the decoding of SSLv3 and TLS CBC records constant
time. Without this, a timing side-channel can be used to build a padding
oracle and mount Vaudenay's attack.
This patch also disables the stitched AESNI+SHA mode pending a similar
fix to that code.
In order to be easy to backport, this change is implemented in ssl/,
rather than as a generic AEAD mode. In the future this should be changed
around so that HMAC isn't in ssl/, but crypto/ as FIPS expects.
(cherry picked from commit e130841bcc)
client hello message. Previously this could only be retrieved on an initial
connection and it was impossible to determine the cipher IDs of any uknown
ciphersuites.
by a certificate chain. Add additional tests to handle client
certificates: checks for matching certificate type and issuer name
comparison.
Print out results of checks for each candidate chain tested in
s_server/s_client.
possible to have different stores per SSL structure or one store in
the parent SSL_CTX. Include distint stores for certificate chain
verification and chain building. New ctrl SSL_CTRL_BUILD_CERT_CHAIN
to build and store a certificate chain in CERT structure: returing
an error if the chain cannot be built: this will allow applications
to test if a chain is correctly configured.
Note: if the CERT based stores are not set then the parent SSL_CTX
store is used to retain compatibility with existing behaviour.
details in s_client.
Also add ctrl to set client certificate types. If not used sensible values
will be included based on supported signature algorithms: for example if
we don't include any DSA signing algorithms the DSA certificate type is
omitted.
Fix restriction in old code where certificate types would be truncated
if it exceeded TLS_CT_NUMBER.
the permitted signature algorithms for server and client authentication
are the same but it is now possible to set different algorithms for client
authentication only.
is required by client or server. An application can decide which
certificate chain to present based on arbitrary criteria: for example
supported signature algorithms. Add very simple example to s_server.
This fixes many of the problems and restrictions of the existing client
certificate callback: for example you can now clear existing certificates
and specify the whole chain.
the certificate can be used for (if anything). Set valid_flags field
in new tls1_check_chain function. Simplify ssl_set_cert_masks which used
to have similar checks in it.
Add new "cert_flags" field to CERT structure and include a "strict mode".
This enforces some TLS certificate requirements (such as only permitting
certificate signature algorithms contained in the supported algorithms
extension) which some implementations ignore: this option should be used
with caution as it could cause interoperability issues.
Only store encoded versions of peer and configured signature algorithms.
Determine shared signature algorithms and cache the result along with NID
equivalents of each algorithm.
TLS v1.2. These are sent as an extension for clients and during a certificate
request for servers.
TODO: add support for shared signature algorithms, respect shared algorithms
when deciding which ciphersuites and certificates to permit.
enabled instead of requiring an application to hard code a (possibly
inappropriate) parameter set and delve into EC internals we just
automatically use the preferred curve.
