mod_ssl: use ASN1_STRING accessor API in dump_extn_value:

* modules/ssl/ssl_engine_vars.c (dump_extn_value): Use
  ASN1_STRING_get0_data() and ASN1_STRING_length() rather than
  directly dereferencing the ASN1_OCTET_STRING structure, which is
  opaque in OpenSSL 4.0.
* modules/ssl/ssl_private.h: Add compat macros for
  ASN1_STRING_get0_data and ASN1_STRING_length for pre-1.1 API.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: notroj

modules/ssl/ssl_engine_vars.c

@@ -1244,17 +1244,17 @@ void modssl_var_extract_san_entries(apr_table_t *t, SSL *ssl, apr_pool_t *p)
  * success and writes the string to the given bio. */
 static int dump_extn_value(BIO *bio, ASN1_OCTET_STRING *str)
 {
-    const unsigned char *pp = str->data;
+    const unsigned char *pp = ASN1_STRING_get0_data(str);
     ASN1_STRING *ret = ASN1_STRING_new();
     int rv = 0;
 
-    if(!ret) {
-      return rv;
+    if (!ret) {
+        return rv;
     }
 
     /* This allows UTF8String, IA5String, VisibleString, or BMPString;
      * conversion to UTF-8 is forced. */
-    if (d2i_DISPLAYTEXT(&ret, &pp, str->length)) {
+    if (d2i_DISPLAYTEXT(&ret, &pp, ASN1_STRING_length(str))) {
         ASN1_STRING_print_ex(bio, ret, ASN1_STRFLGS_UTF8_CONVERT);
         rv = 1;
     }

modules/ssl/ssl_private.h

@@ -282,6 +282,8 @@
 #define DH_bits(x)                 (BN_num_bits(x->p))
 #define X509_up_ref(x)             (CRYPTO_add(&(x)->references, +1, CRYPTO_LOCK_X509))
 #define EVP_PKEY_up_ref(pk)        (CRYPTO_add(&(pk)->references, +1, CRYPTO_LOCK_EVP_PKEY))
+#define ASN1_STRING_get0_data(x)   ((x)->data)
+#define ASN1_STRING_length(x)      ((int)(x)->length)
 #else
 void init_bio_methods(void);
 void free_bio_methods(void);