Go into the error state if a fatal alert is sent or received

If an application calls SSL_shutdown after a fatal alert has occured and then behaves different based on error codes from that function then the application may be vulnerable to a padding oracle. CVE-2019-1559 Reviewed-by: Richard Levitte <levitte@openssl.org>
openssl · Dec 14, 2018 · e9bbefbf0f24c57645e7ad6a5a71ae649d18ac8e · e9bbefb
1 parent c81f169
commit e9bbefbf0f24c57645e7ad6a5a71ae649d18ac8e
Unified Split

Showing with 8 additions and 3 deletions.

+1 −0 ssl/d1_pkt.c

+7 −3 ssl/s3_pkt.c
diff --git a/ssl/d1_pkt.c b/ssl/d1_pkt.c
@@ -1309,6 +1309,7 @@ int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
            ERR_add_error_data(2, "SSL alert number ", tmp);
            s->shutdown |= SSL_RECEIVED_SHUTDOWN;
            SSL_CTX_remove_session(s->session_ctx, s->session);
+  
+            s->state = SSL_ST_ERR;
            return (0);
        } else {
            al = SSL_AD_ILLEGAL_PARAMETER;

diff --git a/ssl/s3_pkt.c b/ssl/s3_pkt.c
@@ -1500,6 +1500,7 @@ int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
            ERR_add_error_data(2, "SSL alert number ", tmp);
            s->shutdown |= SSL_RECEIVED_SHUTDOWN;
            SSL_CTX_remove_session(s->session_ctx, s->session);
+  
+            s->state = SSL_ST_ERR;
            return (0);
        } else {
            al = SSL_AD_ILLEGAL_PARAMETER;
@@ -1719,9 +1720,12 @@ int ssl3_send_alert(SSL *s, int level, int desc)
                                          * protocol_version alerts */
    if (desc < 0)
        return -1;
-  
-    /* If a fatal one, remove from cache */
-  
-    if ((level == 2) && (s->session != NULL))
-  
-        SSL_CTX_remove_session(s->session_ctx, s->session);
+  
+    /* If a fatal one, remove from cache and go into the error state */
+  
+    if (level == SSL3_AL_FATAL) {
+  
+        if (s->session != NULL)
+  
+            SSL_CTX_remove_session(s->session_ctx, s->session);
+  
+        s->state = SSL_ST_ERR;
+  
+    }
    s->s3->alert_dispatch = 1;
    s->s3->send_alert[0] = level;