[nginx] OCSP stapling: staple now extracted via SSL_get_certificate().

[Maxim Dounin]

details:   http://hg.nginx.org/nginx/rev/a2d5d45f1525
branches:  
changeset: 6546:a2d5d45f1525
user:      Maxim Dounin <mdounin at mdounin.ru>
date:      Thu May 19 14:46:32 2016 +0300
description:
OCSP stapling: staple now extracted via SSL_get_certificate().

This makes it possible to properly return OCSP staple with multiple
certificates configured.

Note that it only works properly in OpenSSL 1.0.1d+, 1.0.0k, 0.9.8y+.
In older versions SSL_get_certificate() fails to return correct certificate
when the certificate status callback is called.

diffstat:

 src/event/ngx_event_openssl_stapling.c |  10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)

diffs (36 lines):

diff --git a/src/event/ngx_event_openssl_stapling.c b/src/event/ngx_event_openssl_stapling.c
--- a/src/event/ngx_event_openssl_stapling.c
+++ b/src/event/ngx_event_openssl_stapling.c
@@ -185,7 +185,6 @@ ngx_ssl_stapling(ngx_conf_t *cf, ngx_ssl
 done:
 
     SSL_CTX_set_tlsext_status_cb(ssl->ctx, ngx_ssl_certificate_status_callback);
-    SSL_CTX_set_tlsext_status_arg(ssl->ctx, staple);
 
     return NGX_OK;
 }
@@ -455,6 +454,7 @@ static int
 ngx_ssl_certificate_status_callback(ngx_ssl_conn_t *ssl_conn, void *data)
 {
     int                  rc;
+    X509                *cert;
     u_char              *p;
     ngx_connection_t    *c;
     ngx_ssl_stapling_t  *staple;
@@ -464,9 +464,15 @@ ngx_ssl_certificate_status_callback(ngx_
     ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, 0,
                    "SSL certificate status callback");
 
-    staple = data;
     rc = SSL_TLSEXT_ERR_NOACK;
 
+    cert = SSL_get_certificate(ssl_conn);
+    staple = X509_get_ex_data(cert, ngx_ssl_stapling_index);
+
+    if (staple == NULL) {
+        return rc;
+    }
+
     if (staple->staple.len
         && staple->valid >= ngx_time())
     {