The only support for SSLv2 left is receiving a SSLv2 compatible client hello.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

than the mtu we are already using
Reviewed-by: NTim Hudson <tjh@openssl.org>

we will support then dtls1_do_write can go into an infinite loop. This commit
fixes that.
Reviewed-by: NTim Hudson <tjh@openssl.org>

at least the minimum or it will fail.
There were some instances in dtls1_query_mtu where the final mtu can end up
being less than the minimum, i.e. where the user has set an mtu manually. This
shouldn't be allowed. Also remove dtls1_guess_mtu that, despite having
logic for guessing an mtu, was actually only ever used to work out the minimum
mtu to use.
Reviewed-by: NTim Hudson <tjh@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: NTim Hudson <tjh@openssl.org>

mtu that we have received is not less than the minimum. If its less it uses the
minimum instead. The second call to query the mtu does not do that, but
instead uses whatever comes back. We have seen an instance in RT#3592 where we
have got an unreasonably small mtu come back. This commit makes both query
checks consistent.
Reviewed-by: NTim Hudson <tjh@openssl.org>

automatically updated, and we should use the one provided instead.
Unfortunately there are a couple of locations where this is not respected.
Reviewed-by: NTim Hudson <tjh@openssl.org>

RT#3592 provides an instance where the OPENSSL_assert that this commit
replaces can be hit. I was able to recreate this issue by forcing the
underlying BIO to misbehave and come back with very small mtu values. This
happens the second time around the while loop after we have detected that the
MTU has been exceeded following the call to dtls1_write_bytes.
Reviewed-by: NTim Hudson <tjh@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

Previously, state variant was not advanced, which resulted in state
being stuck in the st1 variant (usually "_A").

This broke certificate callback retry logic when accepting connections
that were using SSLv2 ClientHello (hence reusing the message), because
their state never advanced to SSL3_ST_SR_CLNT_HELLO_C variant required
for the retry code path.

Reported by Yichun Zhang (agentzh).
Signed-off-by: NPiotr Sikora <piotr@cloudflare.com>
Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>

PR#1767
Reviewed-by: NRichard Levitte <levitte@openssl.org>

PR#3613
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NDr. Stephen Henson <steve@openssl.org>

PR#3608
Reviewed-by: NTim Hudson <tjh@openssl.org>

PR#3574
Reviewed-by: NDr. Stephen Henson <steve@openssl.org>

Reviewed-by: NMatt Caswell <matt@openssl.org>

the session's version (server).

See also BoringSSL's commit bdf5e72f50e25f0e45e825c156168766d8442dde.
Reviewed-by: NDr. Stephen Henson <steve@openssl.org>

once the ChangeCipherSpec message is received. Previously, the server would
set the flag once at SSL3_ST_SR_CERT_VRFY and again at SSL3_ST_SR_FINISHED.
This would allow a second CCS to arrive and would corrupt the server state.

(Because the first CCS would latch the correct keys and subsequent CCS
messages would have to be encrypted, a MitM attacker cannot exploit this,
though.)

Thanks to Joeri de Ruiter for reporting this issue.
Reviewed-by: NMatt Caswell <matt@openssl.org>

The server must send a NewSessionTicket message if it advertised one
in the ServerHello, so make a missing ticket message an alert
in the client.

An equivalent change was independently made in BoringSSL, see commit
6444287806d801b9a45baf1f6f02a0e3a16e144c.
Reviewed-by: NMatt Caswell <matt@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: NMatt Caswell <matt@openssl.org>

The same change was independently made in BoringSSL, see commit
9eaeef81fa2d4fd6246dc02b6203fa936a5eaf67
Reviewed-by: NMatt Caswell <matt@openssl.org>

This ensures that it's zeroed even if the SSL object is reused
(as in ssltest.c). It also ensures that it applies to DTLS, too.
Reviewed-by: NMatt Caswell <matt@openssl.org>

When no-ssl3 is set only make SSLv3 disabled by default. Retain -ssl3
options for s_client/s_server/ssltest.

When no-ssl3-method is set SSLv3_*method() is removed and all -ssl3
options.

We should document this somewhere, e.g. wiki, FAQ or manual page.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Don't send or parse any extensions other than RI (which is needed
to handle secure renegotation) for SSLv3.
Reviewed-by: NMatt 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: NMatt Caswell <matt@openssl.org>

(cherry picked from commit 56e8dc542bd693b2dccea8828b3d8e5fc6932d0c)

Conflicts:
	ssl/ssl.h
	ssl/ssl_err.c

Reviewed-by: NDr. Stephen Henson <steve@openssl.org>

Reviewed-by: NMatt Caswell <matt@openssl.org>

Reviewed-by: NDr. Stephen Henson <steve@openssl.org>

Print out more details of the conection in ssltest specifically:
server certificate curve name for EC, server temporary key (if any)
and peer signing digest.
Reviewed-by: NMatt Caswell <matt@openssl.org>

Add command line support for SSL_CONF: server side arguments are
prefixed by -s_ (e.g. -s_no_ssl3) and client side with -c_.
Reviewed-by: NMatt Caswell <matt@openssl.org>

Tighten client-side session ticket handling during renegotiation:
ensure that the client only accepts a session ticket if the server sends
the extension anew in the ServerHello. Previously, a TLS client would
reuse the old extension state and thus accept a session ticket if one was
announced in the initial ServerHello.
Reviewed-by: NBodo Moeller <bodo@openssl.org>

Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NGeoff Thorpe <geoff@openssl.org>

SSL_set_SSL_CTX is used to change the SSL_CTX for SNI, keep the
supported signature algorithms and raw cipherlist.
Reviewed-by: NTim Hudson <tjh@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

Reviewed-by: NRich Salz <rsalz@openssl.org>