Remove cipher from SSL_SESSION.

For a long time SSL_SESSION has had both a cipher ID and a pointer to
an SSL_CIPHER (and not both are guaranteed to be populated). There is also
a pointer to an SSL_CIPHER in the SSL_HANDSHAKE that denotes the cipher
being used for this connection. Some code has been using the cipher from
SSL_SESSION and some code has been using the cipher from SSL_HANDSHAKE.

Remove cipher from SSL_SESSION and use the version in SSL_HANDSHAKE
everywhere. If resuming from a session then we need to use the SSL_SESSION
cipher ID to set the SSL_HANDSHAKE cipher. And we still need to ensure that
we update the cipher ID in the SSL_SESSION whenever the SSL_HANDSHAKE
cipher changes (this only occurs in a few places).

ok tb@

1 files changed, 10 insertions, 8 deletions

diff --git a/src/lib/libssl/t1_enc.c b/src/lib/libssl/t1_enc.c
index c6140e9b34..64e1dd5b63 100644
--- a/src/lib/libssl/t1_enc.c
+++ b/src/lib/libssl/t1_enc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: t1_enc.c,v 1.157 2022/11/26 16:08:56 tb Exp $ */
+/* $OpenBSD: t1_enc.c,v 1.158 2024/07/20 04:04:23 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -357,15 +357,17 @@ tls1_setup_key_block(SSL *s)
         if (s->s3->hs.tls12.key_block != NULL)
                 return (1);
 
-        if (s->session->cipher &&
-            (s->session->cipher->algorithm_mac & SSL_AEAD)) {
-                if (!ssl_cipher_get_evp_aead(s->session, &aead)) {
+        if (s->s3->hs.cipher == NULL)
+                return (0);
+
+        if ((s->s3->hs.cipher->algorithm_mac & SSL_AEAD) != 0) {
+                if (!ssl_cipher_get_evp_aead(s, &aead)) {
                         SSLerror(s, SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
                         return (0);
                 }
         } else {
                 /* XXX - mac_type and mac_secret_size are now unused. */
-                if (!ssl_cipher_get_evp(s->session, &cipher, &mac_hash,
+                if (!ssl_cipher_get_evp(s, &cipher, &mac_hash,
                     &mac_type, &mac_secret_size)) {
                         SSLerror(s, SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
                         return (0);
@@ -395,12 +397,12 @@ tls1_setup_key_block(SSL *s)
                  */
                 s->s3->need_empty_fragments = 1;
 
-                if (s->session->cipher != NULL) {
-                        if (s->session->cipher->algorithm_enc == SSL_eNULL)
+                if (s->s3->hs.cipher != NULL) {
+                        if (s->s3->hs.cipher->algorithm_enc == SSL_eNULL)
                                 s->s3->need_empty_fragments = 0;
 
 #ifndef OPENSSL_NO_RC4
-                        if (s->session->cipher->algorithm_enc == SSL_RC4)
+                        if (s->s3->hs.cipher->algorithm_enc == SSL_RC4)
                                 s->s3->need_empty_fragments = 0;
 #endif
                 }