Check session_cert is not NULL before dereferencing it.

Unnecessary recursion when receiving a DTLS hello request can be used to
crash a DTLS client. Fixed by handling DTLS hello request without recursion.

Thanks to Imre Rad (Search-Lab Ltd.) for discovering this issue.

Return a fatal error if an attempt is made to use a zero length
master secret.

Only accept change cipher spec when it is expected instead of at any
time. This prevents premature setting of session keys before the master
secret is determined which an attacker could use as a MITM attack.

Thanks to KIKUCHI Masashi (Lepidum Co. Ltd.) for reporting this issue
and providing the initial fix this patch is based on.

A buffer overrun attack can be triggered by sending invalid DTLS fragments
to an OpenSSL DTLS client or server. This is potentially exploitable to
run arbitrary code on a vulnerable client or server.

Fixed by adding consistency check for DTLS fragments.

Thanks to Jüri Aedla for reporting this issue.

PR#3286
(cherry picked from commit 71e95000afb2227fe5cac1c79ae884338bcd8d0b)

As documented PKCS7_NOCERTS should only exclude the signer's certificate
and not any supplied in the "certs" parameter. This makes it possible to
exclude the signer's certificate but include other certificates. Applications
that don't want to include other certificates should set "certs" to NULL
anyway.
(cherry picked from commit 5c6f808b66f1a2e0fb2a508b24b845a88803fe3a)

PR#2677.

PR#3302
(cherry picked from commit 9717f01951f976f76dd40a38d9fc7307057fa4c4)

Delays the queue insertion until after the ssl3_setup_buffers() call due to use-after-free bug. PR#3362

(cherry picked from commit 3009244d)

Make sure there is an extra 4 bytes for server done message when
NETSCAPE_HANG_BUG is defined.

PR#3361
(cherry picked from commit 673c42b2)

the verify app man page didn't describe the usage of attime option
even though it was listed as a valid option in the -help message.

This patch fixes this omission.

While the -help message references this option, the man page
doesn't mention the -no_ecdhe option.
This patch fixes this omission.

PR#3249
(cherry picked from commit 8909bf20269035d295743fca559207ef2eb84eb3)

PR#3278
(cherry picked from commit de56fe797081fc09ebd1add06d6e2df42a324fd5)

(cherry picked from commit 989d87cb)

Use triple DES for certificate encryption if no-rc2 is
specified.

PR#3357
(cherry picked from commit 2e2a6d0ecd8f6984c692078ec2e2683690e0bc59)

PR#3357
(cherry picked from commit ca3ffd9670f2b589bf8cc04923f953e06d6fbc58)

Replace manual ASN.1 decoder with ASN1_get object. This
will decode the tag and length properly and check against
it does not exceed the supplied buffer length.

PR#3335
(cherry picked from commit b0308dddd1cc6a8e1de803ef29ba6da25ee072c2)

PR: 3317

If the key type does not match any CMS recipient type return
an error instead of using a random key (MMA mitigation). This
does not leak any useful information to an attacker.

PR#3348
(cherry picked from commit 83a3182e0560f76548f4378325393461f6275493)