A missing bounds check in the handling of the TLS heartbeat extension
can be used to reveal up to 64k of memory to a connected client or
server.
Thanks for Neel Mehta of Google Security for discovering this bug and to
Adam Langley <agl@chromium.org> and Bodo Moeller <bmoeller@acm.org> for
preparing the fix (CVE-2014-0160)
(cherry picked from commit 96db9023b8)
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.
Don't clear verification errors from the error queue unless
SSL_BUILD_CHAIN_FLAG_CLEAR_ERROR is set.
If errors occur during verification and SSL_BUILD_CHAIN_FLAG_IGNORE_ERROR
is set return 2 so applications can issue warnings.
(cherry picked from commit 2dd6976f6d)
Although the memory allocated by compression methods is fixed and
cannot grow over time it can cause warnings in some leak checking
tools. The function SSL_COMP_free_compression_methods() will free
and zero the list of supported compression methods. This should
*only* be called in a single threaded context when an application
is shutting down to avoid interfering with existing contexts
attempting to look up compression methods.
(cherry picked from commit 976c58302b)
New flags to build certificate chains. The can be used to rearrange
the chain so all an application needs to do is add all certificates
in arbitrary order and then build the chain to check and correct them.
Add verify error code when building chain.
Update docs.
The flag SSL_OP_MSIE_SSLV2_RSA_PADDING hasn't done anything since OpenSSL
0.9.7h but deleting it will break source compatibility with any software
that references it. Restore it but #define to zero.
(cherry picked from commit b17d6b8d1d)
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.
If an application calls the macro SSL_CTX_get_extra_chain_certs
return either the old "shared" extra certificates or those associated
with the current certificate.
This means applications which call SSL_CTX_use_certificate_chain_file
and retrieve the additional chain using SSL_CTX_get_extra_chain_certs
will still work. An application which only wants to check the shared
extra certificates can call the new macro
SSL_CTX_get_extra_chain_certs_only
This allows to process multiple fragmets of maximum fragment size,
as opposite to chopping maximum-sized fragments to multiple smaller
ones. This approach relies on dynamic allocation of larger buffers,
which we trade for performance improvement, for several *times* in
some situations.
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.
