In this commit we just generate the extension on the client side, but don't
yet do anything with it. Subsequent commits, will add the server side
capability.
At the moment we hard code a single key_share. In the future we should make
this configurable.
Reviewed-by: Rich Salz <rsalz@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>
There were a few places where they could be declared const so this commit
does that.
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
The name and type of the argument to ssl_check_for_safari() has changed.
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
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>
ssl_set_handshake_header2() was only ever a temporary name while we had
to have ssl_set_handshake_header() for code that hadn't been converted to
WPACKET yet. No code remains that needed that so we can rename it.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Remove the old ssl_set_handshake_header() implementations. Later we will
rename ssl_set_handshake_header2() to ssl_set_handshake_header().
Reviewed-by: Rich Salz <rsalz@openssl.org>
This was a temporary function needed during the conversion to WPACKET. All
callers have now been converted to the new way of doing this so this
function is no longer required.
Reviewed-by: Rich Salz <rsalz@openssl.org>
If a server sent multiple NPN extensions in a single ClientHello then a
mem leak can occur. This will only happen where the client has requested
NPN in the first place. It does not occur during renegotiation. Therefore
the maximum that could be leaked in a single connection with a malicious
server is 64k (the maximum size of the ServerHello extensions section). As
this is client side, only occurs if NPN has been requested and does not
occur during renegotiation this is unlikely to be exploitable.
Issue reported by Shi Lei.
Reviewed-by: Rich Salz <rsalz@openssl.org>
A malicious client can send an excessively large OCSP Status Request
extension. If that client continually requests renegotiation,
sending a large OCSP Status Request extension each time, then there will
be unbounded memory growth on the server. This will eventually lead to a
Denial Of Service attack through memory exhaustion. Servers with a
default configuration are vulnerable even if they do not support OCSP.
Builds using the "no-ocsp" build time option are not affected.
I have also checked other extensions to see if they suffer from a similar
problem but I could not find any other issues.
CVE-2016-6304
Issue reported by Shi Lei.
Reviewed-by: Rich Salz <rsalz@openssl.org>
All the other functions that take an argument for the number of bytes
use convenience macros for this purpose. We should do the same with
WPACKET_put_bytes().
Reviewed-by: Rich Salz <rsalz@openssl.org>
Updated the construction code to use the new function. Also added some
convenience macros for WPACKET_sub_memcpy().
Reviewed-by: Rich Salz <rsalz@openssl.org>
A few style tweaks here and there. The main change is that curr and
packet_len are now offsets into the buffer to account for the fact that
the pointers can change if the buffer grows. Also dropped support for the
WPACKET_set_packet_len() function. I thought that was going to be needed
but so far it hasn't been. It doesn't really work any more due to the
offsets change.
Reviewed-by: Rich Salz <rsalz@openssl.org>
If a ticket callback changes the HMAC digest to SHA512 the existing
sanity checks are not sufficient and an attacker could perform a DoS
attack with a malformed ticket. Add additional checks based on
HMAC size.
Thanks to Shi Lei for reporting this bug.
CVE-2016-6302
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
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>
When handling ECDH check to see if the curve is "custom" (X25519 is
currently the only curve of this type) and instead of setting a curve
NID just allocate a key of appropriate type.
Reviewed-by: Rich Salz <rsalz@openssl.org>
- Always process ALPN (previously there was an early return in the
certificate status handling)
- Don't send a duplicate alert. Previously, both
ssl_check_clienthello_tlsext_late and its caller would send an
alert. Consolidate alert sending code in the caller.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1264)
When session tickets are used, it's possible that SNI might swtich the
SSL_CTX on an SSL. Normally, this is not a problem, because the
initial_ctx/session_ctx are used for all session ticket/id processes.
However, when the SNI callback occurs, it's possible that the callback
may update the options in the SSL from the SSL_CTX, and this could
cause SSL_OP_NO_TICKET to be set. If this occurs, then two bad things
can happen:
1. The session ticket TLSEXT may not be written when the ticket expected
flag is set. The state machine transistions to writing the ticket, and
the client responds with an error as its not expecting a ticket.
2. When creating the session ticket, if the ticket key cb returns 0
the crypto/hmac contexts are not initialized, and the code crashes when
trying to encrypt the session ticket.
To fix 1, if the ticket TLSEXT is not written out, clear the expected
ticket flag.
To fix 2, consider a return of 0 from the ticket key cb a recoverable
error, and write a 0 length ticket and continue. The client-side code
can explicitly handle this case.
Fix these two cases, and add unit test code to validate ticket behavior.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1098)
