Benjamin Kaduk 2e3ec2e157 Code to thread-safety in ChangeCipherState ... The server-side ChangeCipherState processing stores the new cipher in the SSL_SESSION object, so that the new state can be used if this session gets resumed. However, writing to the session is only thread-safe for initial handshakes, as at other times the session object may be in a shared cache and in use by another thread at the same time. Reflect this invariant in the code by only writing to s->session->cipher when it is currently NULL (we do not cache sessions with no cipher). The code prior to this change would never actually change the (non-NULL) cipher value in a session object, since our server enforces that (pre-TLS-1.3) resumptions use the exact same cipher as the initial connection, and non-abbreviated renegotiations have produced a new session object before we get to this point. Regardless, include logic to detect such a condition and abort the handshake if it occurs, to avoid any risk of inadvertently using the wrong cipher on a connection. Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org> (Merged from https://github.com/openssl/openssl/pull/10943)		2020-03-13 14:20:14 -07:00
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crypto	EVP: Add new domparams and key generation functionality	2020-03-12 10:44:01 +01:00
internal	Extract sk_ASN1_UTF8STRING2text() from ts_get_status_text() in ts_rsp_verify.c to asn1_lib.c	2020-03-10 16:09:44 +01:00
openssl	Code to thread-safety in ChangeCipherState	2020-03-13 14:20:14 -07:00