[nginx] SSL: abort handshake on SSL_set_SSL_CTX() errors.

[Sergey Kandaurov]

details:   https://hg.nginx.org/nginx/rev/eb940fe579cf
branches:  
changeset: 7712:eb940fe579cf
user:      Sergey Kandaurov <pluknet at nginx.com>
date:      Thu Sep 24 13:51:29 2020 +0100
description:
SSL: abort handshake on SSL_set_SSL_CTX() errors.

In rare cases, such as memory allocation failure, SSL_set_SSL_CTX() returns
NULL, which could mean that a different SSL configuration has not been set.
Note that this new behaviour seemingly originated in OpenSSL-1.1.0 release.

diffstat:

 src/http/ngx_http_request.c |  5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diffs (15 lines):

diff -r 526dddf637bb -r eb940fe579cf src/http/ngx_http_request.c
--- a/src/http/ngx_http_request.c	Wed Sep 23 19:52:31 2020 +0300
+++ b/src/http/ngx_http_request.c	Thu Sep 24 13:51:29 2020 +0100
@@ -932,7 +932,10 @@ ngx_http_ssl_servername(ngx_ssl_conn_t *
     c->ssl->buffer_size = sscf->buffer_size;
 
     if (sscf->ssl.ctx) {
-        SSL_set_SSL_CTX(ssl_conn, sscf->ssl.ctx);
+        if (SSL_set_SSL_CTX(ssl_conn, sscf->ssl.ctx) == NULL) {
+            *ad = SSL_AD_INTERNAL_ERROR;
+            return SSL_TLSEXT_ERR_ALERT_FATAL;
+        }
 
         /*
          * SSL_set_SSL_CTX() only changes certs as of 1.0.0d