From dee1eb37d787d34cb37df7eab535240e1774293a Mon Sep 17 00:00:00 2001
From: Ruediger Pluem <rpluem@apache.org>
Date: Mon, 8 Apr 2024 13:18:28 +0000
Subject: [PATCH] * Ensure that we set the default DH parameters for the key

Replace else with an if as the if branch no longer ensures that
custome DH parameters have been loaded.
This fixes a regression that causes the default DH parameters for a key
no longer set and thus effectively disabling DH ciphers when no explicit
DH parameters are set.

PR: 68863


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1916863 13f79535-47bb-0310-9956-ffa450edef68
---
 changes-entries/pr68863.txt   |  3 +++
 modules/ssl/ssl_engine_init.c | 11 ++++++-----
 2 files changed, 9 insertions(+), 5 deletions(-)
 create mode 100644 changes-entries/pr68863.txt

diff --git a/changes-entries/pr68863.txt b/changes-entries/pr68863.txt
new file mode 100644
index 00000000000..d45ffc708cc
--- /dev/null
+++ b/changes-entries/pr68863.txt
@@ -0,0 +1,3 @@
+  *) mod_ssl: Fix a regression that causes the default DH parameters for a key
+     no longer set and thus effectively disabling DH ciphers when no explicit
+     DH parameters are set. PR 68863 [Ruediger Pluem]
diff --git a/modules/ssl/ssl_engine_init.c b/modules/ssl/ssl_engine_init.c
index 64e4aaf1dcd..f657026d137 100644
--- a/modules/ssl/ssl_engine_init.c
+++ b/modules/ssl/ssl_engine_init.c
@@ -1416,6 +1416,7 @@ static apr_status_t ssl_init_server_certs(server_rec *s,
     const char *vhost_id = mctx->sc->vhost_id, *key_id, *certfile, *keyfile;
     int i;
     EVP_PKEY *pkey;
+    int custom_dh_done = 0;
 #ifdef HAVE_ECC
     EC_GROUP *ecgroup = NULL;
     int curve_nid = 0;
@@ -1591,14 +1592,14 @@ static apr_status_t ssl_init_server_certs(server_rec *s,
      */
     certfile = APR_ARRAY_IDX(mctx->pks->cert_files, 0, const char *);
     if (certfile && !modssl_is_engine_id(certfile)) {
-        int done = 0, num_bits = 0;
+        int num_bits = 0;
 #if OPENSSL_VERSION_NUMBER < 0x30000000L
         DH *dh = modssl_dh_from_file(certfile);
         if (dh) {
             num_bits = DH_bits(dh);
             SSL_CTX_set_tmp_dh(mctx->ssl_ctx, dh);
             DH_free(dh);
-            done = 1;
+            custom_dh_done = 1;
         }
 #else
         pkey = modssl_dh_pkey_from_file(certfile);
@@ -1608,18 +1609,18 @@ static apr_status_t ssl_init_server_certs(server_rec *s,
                 EVP_PKEY_free(pkey);
             }
             else {
-                done = 1;
+                custom_dh_done = 1;
             }
         }
 #endif
-        if (done) {
+        if (custom_dh_done) {
             ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, APLOGNO(02540)
                          "Custom DH parameters (%d bits) for %s loaded from %s",
                          num_bits, vhost_id, certfile);
         }
     }
 #if !MODSSL_USE_OPENSSL_PRE_1_1_API
-    else {
+    if (!custom_dh_done) {
         /* If no parameter is manually configured, enable auto
          * selection. */
         SSL_CTX_set_dh_auto(mctx->ssl_ctx, 1);