Make LHASH_OF() and STACK_OF() use opaque structs

This removes internals of these two special snowflakes and will allow
further simplifications. Unfortunately, there are some pieces of
software that actually use LHASH_OF() (looking at you, pound, Ruby, and
openssl(1)), so we get to keep exposing this garbage, at least for now.

Expose lh_error() as a symbol to replace a macro reaching into _LHASH.
lh_down_load() is no longer available. _LHASH and _STACK are now opaque,
LHASH_NODE becomes internal-only.

from jsing

4 files changed, 79 insertions, 30 deletions

diff --git a/src/lib/libcrypto/stack/safestack.h b/src/lib/libcrypto/stack/safestack.h
index b64b865dc8..61770ef36f 100644
--- a/src/lib/libcrypto/stack/safestack.h
+++ b/src/lib/libcrypto/stack/safestack.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: safestack.h,v 1.30 2024/03/02 11:04:52 tb Exp $ */
+/* $OpenBSD: safestack.h,v 1.31 2024/03/02 11:11:11 tb Exp $ */
 /* ====================================================================
  * Copyright (c) 1999 The OpenSSL Project.  All rights reserved.
  *
@@ -84,16 +84,8 @@
 #define STACK_OF(type) struct stack_st_##type
 #define PREDECLARE_STACK_OF(type) STACK_OF(type);
 
-#define DECLARE_STACK_OF(type) \
-STACK_OF(type) \
-    { \
-    _STACK stack; \
-    };
-#define DECLARE_SPECIAL_STACK_OF(type, type2) \
-STACK_OF(type) \
-    { \
-    _STACK stack; \
-    };
+#define DECLARE_STACK_OF(type) STACK_OF(type);
+#define DECLARE_SPECIAL_STACK_OF(type, type2) STACK_OF(type);
 
 #define IMPLEMENT_STACK_OF(type) /* nada (obsolete in new safestack approach)*/
 
@@ -1815,7 +1807,6 @@ DECLARE_SPECIAL_STACK_OF(OPENSSL_STRING, char)
   LHM_lh_doall_arg(ADDED_OBJ,lh,fn,arg_type,arg)
 #define lh_ADDED_OBJ_error(lh) LHM_lh_error(ADDED_OBJ,lh)
 #define lh_ADDED_OBJ_num_items(lh) LHM_lh_num_items(ADDED_OBJ,lh)
-#define lh_ADDED_OBJ_down_load(lh) LHM_lh_down_load(ADDED_OBJ,lh)
 #define lh_ADDED_OBJ_free(lh) LHM_lh_free(ADDED_OBJ,lh)
 
 #define lh_CONF_VALUE_new() LHM_lh_new(CONF_VALUE,conf_value)
@@ -1827,7 +1818,6 @@ DECLARE_SPECIAL_STACK_OF(OPENSSL_STRING, char)
   LHM_lh_doall_arg(CONF_VALUE,lh,fn,arg_type,arg)
 #define lh_CONF_VALUE_error(lh) LHM_lh_error(CONF_VALUE,lh)
 #define lh_CONF_VALUE_num_items(lh) LHM_lh_num_items(CONF_VALUE,lh)
-#define lh_CONF_VALUE_down_load(lh) LHM_lh_down_load(CONF_VALUE,lh)
 #define lh_CONF_VALUE_free(lh) LHM_lh_free(CONF_VALUE,lh)
 
 #define lh_ERR_STATE_new() LHM_lh_new(ERR_STATE,err_state)
@@ -1839,7 +1829,6 @@ DECLARE_SPECIAL_STACK_OF(OPENSSL_STRING, char)
   LHM_lh_doall_arg(ERR_STATE,lh,fn,arg_type,arg)
 #define lh_ERR_STATE_error(lh) LHM_lh_error(ERR_STATE,lh)
 #define lh_ERR_STATE_num_items(lh) LHM_lh_num_items(ERR_STATE,lh)
-#define lh_ERR_STATE_down_load(lh) LHM_lh_down_load(ERR_STATE,lh)
 #define lh_ERR_STATE_free(lh) LHM_lh_free(ERR_STATE,lh)
 
 #define lh_ERR_STRING_DATA_new() LHM_lh_new(ERR_STRING_DATA,err_string_data)
@@ -1851,7 +1840,6 @@ DECLARE_SPECIAL_STACK_OF(OPENSSL_STRING, char)
   LHM_lh_doall_arg(ERR_STRING_DATA,lh,fn,arg_type,arg)
 #define lh_ERR_STRING_DATA_error(lh) LHM_lh_error(ERR_STRING_DATA,lh)
 #define lh_ERR_STRING_DATA_num_items(lh) LHM_lh_num_items(ERR_STRING_DATA,lh)
-#define lh_ERR_STRING_DATA_down_load(lh) LHM_lh_down_load(ERR_STRING_DATA,lh)
 #define lh_ERR_STRING_DATA_free(lh) LHM_lh_free(ERR_STRING_DATA,lh)
 
 #define lh_EX_CLASS_ITEM_new() LHM_lh_new(EX_CLASS_ITEM,ex_class_item)
@@ -1863,7 +1851,6 @@ DECLARE_SPECIAL_STACK_OF(OPENSSL_STRING, char)
   LHM_lh_doall_arg(EX_CLASS_ITEM,lh,fn,arg_type,arg)
 #define lh_EX_CLASS_ITEM_error(lh) LHM_lh_error(EX_CLASS_ITEM,lh)
 #define lh_EX_CLASS_ITEM_num_items(lh) LHM_lh_num_items(EX_CLASS_ITEM,lh)
-#define lh_EX_CLASS_ITEM_down_load(lh) LHM_lh_down_load(EX_CLASS_ITEM,lh)
 #define lh_EX_CLASS_ITEM_free(lh) LHM_lh_free(EX_CLASS_ITEM,lh)
 
 #define lh_FUNCTION_new() LHM_lh_new(FUNCTION,function)
@@ -1875,7 +1862,6 @@ DECLARE_SPECIAL_STACK_OF(OPENSSL_STRING, char)
   LHM_lh_doall_arg(FUNCTION,lh,fn,arg_type,arg)
 #define lh_FUNCTION_error(lh) LHM_lh_error(FUNCTION,lh)
 #define lh_FUNCTION_num_items(lh) LHM_lh_num_items(FUNCTION,lh)
-#define lh_FUNCTION_down_load(lh) LHM_lh_down_load(FUNCTION,lh)
 #define lh_FUNCTION_free(lh) LHM_lh_free(FUNCTION,lh)
 
 #define lh_OBJ_NAME_new() LHM_lh_new(OBJ_NAME,obj_name)
@@ -1887,7 +1873,6 @@ DECLARE_SPECIAL_STACK_OF(OPENSSL_STRING, char)
   LHM_lh_doall_arg(OBJ_NAME,lh,fn,arg_type,arg)
 #define lh_OBJ_NAME_error(lh) LHM_lh_error(OBJ_NAME,lh)
 #define lh_OBJ_NAME_num_items(lh) LHM_lh_num_items(OBJ_NAME,lh)
-#define lh_OBJ_NAME_down_load(lh) LHM_lh_down_load(OBJ_NAME,lh)
 #define lh_OBJ_NAME_free(lh) LHM_lh_free(OBJ_NAME,lh)
 
 #define lh_OPENSSL_STRING_new() LHM_lh_new(OPENSSL_STRING,openssl_string)
@@ -1899,7 +1884,6 @@ DECLARE_SPECIAL_STACK_OF(OPENSSL_STRING, char)
   LHM_lh_doall_arg(OPENSSL_STRING,lh,fn,arg_type,arg)
 #define lh_OPENSSL_STRING_error(lh) LHM_lh_error(OPENSSL_STRING,lh)
 #define lh_OPENSSL_STRING_num_items(lh) LHM_lh_num_items(OPENSSL_STRING,lh)
-#define lh_OPENSSL_STRING_down_load(lh) LHM_lh_down_load(OPENSSL_STRING,lh)
 #define lh_OPENSSL_STRING_free(lh) LHM_lh_free(OPENSSL_STRING,lh)
 
 #define lh_SSL_SESSION_new() LHM_lh_new(SSL_SESSION,ssl_session)
@@ -1911,7 +1895,6 @@ DECLARE_SPECIAL_STACK_OF(OPENSSL_STRING, char)
   LHM_lh_doall_arg(SSL_SESSION,lh,fn,arg_type,arg)
 #define lh_SSL_SESSION_error(lh) LHM_lh_error(SSL_SESSION,lh)
 #define lh_SSL_SESSION_num_items(lh) LHM_lh_num_items(SSL_SESSION,lh)
-#define lh_SSL_SESSION_down_load(lh) LHM_lh_down_load(SSL_SESSION,lh)
 #define lh_SSL_SESSION_free(lh) LHM_lh_free(SSL_SESSION,lh)
 
 #endif /* !defined HEADER_SAFESTACK_H */
diff --git a/src/lib/libcrypto/stack/stack.c b/src/lib/libcrypto/stack/stack.c
index 86117f07a7..99bb52dcfa 100644
--- a/src/lib/libcrypto/stack/stack.c
+++ b/src/lib/libcrypto/stack/stack.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: stack.c,v 1.26 2024/03/02 09:47:16 tb Exp $ */
+/* $OpenBSD: stack.c,v 1.27 2024/03/02 11:11:11 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -63,6 +63,8 @@
 #include <openssl/objects.h>
 #include <openssl/stack.h>
 
+#include "stack_local.h"
+
 #undef MIN_NODES
 #define MIN_NODES       4
 
diff --git a/src/lib/libcrypto/stack/stack.h b/src/lib/libcrypto/stack/stack.h
index 6bea6348f2..8b490c7225 100644
--- a/src/lib/libcrypto/stack/stack.h
+++ b/src/lib/libcrypto/stack/stack.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: stack.h,v 1.9 2014/06/12 15:49:30 deraadt Exp $ */
+/* $OpenBSD: stack.h,v 1.10 2024/03/02 11:11:11 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -63,14 +63,7 @@
 extern "C" {
 #endif
 
-typedef struct stack_st {
-        int num;
-        char **data;
-        int sorted;
-
-        int num_alloc;
-        int (*comp)(const void *, const void *);
-} _STACK;  /* Use STACK_OF(...) instead */
+typedef struct stack_st _STACK;
 
 #define M_sk_num(sk)            ((sk) ? (sk)->num:-1)
 #define M_sk_value(sk,n)        ((sk) ? (sk)->data[n] : NULL)
diff --git a/src/lib/libcrypto/stack/stack_local.h b/src/lib/libcrypto/stack/stack_local.h
new file mode 100644
index 0000000000..a330707192
--- /dev/null
+++ b/src/lib/libcrypto/stack/stack_local.h
@@ -0,0 +1,71 @@
+/* $OpenBSD: stack_local.h,v 1.1 2024/03/02 11:11:11 tb Exp $ */
+/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
+ * All rights reserved.
+ *
+ * This package is an SSL implementation written
+ * by Eric Young (eay@cryptsoft.com).
+ * The implementation was written so as to conform with Netscapes SSL.
+ *
+ * This library is free for commercial and non-commercial use as long as
+ * the following conditions are aheared to.  The following conditions
+ * apply to all code found in this distribution, be it the RC4, RSA,
+ * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
+ * included with this distribution is covered by the same copyright terms
+ * except that the holder is Tim Hudson (tjh@cryptsoft.com).
+ *
+ * Copyright remains Eric Young's, and as such any Copyright notices in
+ * the code are not to be removed.
+ * If this package is used in a product, Eric Young should be given attribution
+ * as the author of the parts of the library used.
+ * This can be in the form of a textual message at program startup or
+ * in documentation (online or textual) provided with the package.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *    "This product includes cryptographic software written by
+ *     Eric Young (eay@cryptsoft.com)"
+ *    The word 'cryptographic' can be left out if the rouines from the library
+ *    being used are not cryptographic related :-).
+ * 4. If you include any Windows specific code (or a derivative thereof) from
+ *    the apps directory (application code) you must include an acknowledgement:
+ *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * The licence and distribution terms for any publically available version or
+ * derivative of this code cannot be changed.  i.e. this code cannot simply be
+ * copied and put under another distribution licence
+ * [including the GNU Public Licence.]
+ */
+
+#ifndef HEADER_STACK_LOCAL_H
+#define HEADER_STACK_LOCAL_H
+
+struct stack_st {
+        int num;
+        char **data;
+        int sorted;
+
+        int num_alloc;
+        int (*comp)(const void *, const void *);
+} /* _STACK */;
+
+#endif