Fix safestack issues in ssl.h

We fix 3 problems with safestack:
- Including an openssl header file without linking against libcrypto
  can cause compilation failures (even if the app does not otherwise need
  to link against libcrypto). See issue #8102
- Recent changes means that applications in no-deprecated builds will need
  to include additional macro calls in the source code for all stacks that
  they need to use - which is an API break. This changes avoids that
  necessity.
- It is not possible to write code using stacks that works in both a
  no-deprecated and a normal build of OpenSSL. See issue #12707.

Fixes #12707
Contains a partial fix for #8102. A similar PR will be needed for hash to
fully fix.

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/12781)

1 files changed, 92 insertions, 0 deletions

diff --git a/util/perl/OpenSSL/stackhash.pm b/util/perl/OpenSSL/stackhash.pm
new file mode 100644
index 0000000000..d8ca76aa91
--- /dev/null
+++ b/util/perl/OpenSSL/stackhash.pm
@@ -0,0 +1,92 @@
+#! /usr/bin/env perl
+# Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
+#
+# Licensed under the Apache License 2.0 (the "License").  You may not use
+# this file except in compliance with the License.  You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
+package OpenSSL::stackhash;
+
+use strict;
+use warnings;
+
+require Exporter;
+our @ISA = qw(Exporter);
+our @EXPORT_OK = qw(generate_stack_macros generate_const_stack_macros);
+
+sub generate_stack_macros_int {
+    my $nametype = shift;
+    my $realtype = shift;
+    my $plaintype = shift;
+
+    my $macros = <<END_MACROS;
+STACK_OF(${nametype});
+typedef int (*sk_${nametype}_compfunc)(const ${plaintype} * const *a, const ${plaintype} *const *b);
+typedef void (*sk_${nametype}_freefunc)(${plaintype} *a);
+typedef ${plaintype} * (*sk_${nametype}_copyfunc)(const ${plaintype} *a);
+static ossl_unused ossl_inline ${realtype} *ossl_check_${nametype}_type(${realtype} *ptr)
+{
+    return ptr;
+}
+static ossl_unused ossl_inline const OPENSSL_STACK *ossl_check_const_${nametype}_sk_type(const STACK_OF(${nametype}) *sk)
+{
+    return (const OPENSSL_STACK *)sk;
+}
+static ossl_unused ossl_inline OPENSSL_STACK *ossl_check_${nametype}_sk_type(STACK_OF(${nametype}) *sk)
+{
+    return (OPENSSL_STACK *)sk;
+}
+static ossl_unused ossl_inline OPENSSL_sk_compfunc ossl_check_${nametype}_compfunc_type(sk_${nametype}_compfunc cmp)
+{
+    return (OPENSSL_sk_compfunc)cmp;
+}
+static ossl_unused ossl_inline OPENSSL_sk_copyfunc ossl_check_${nametype}_copyfunc_type(sk_${nametype}_copyfunc cpy)
+{
+    return (OPENSSL_sk_copyfunc)cpy;
+}
+static ossl_unused ossl_inline OPENSSL_sk_freefunc ossl_check_${nametype}_freefunc_type(sk_${nametype}_freefunc fr)
+{
+    return (OPENSSL_sk_freefunc)fr;
+}
+#define sk_${nametype}_num(sk) OPENSSL_sk_num(ossl_check_const_${nametype}_sk_type(sk))
+#define sk_${nametype}_value(sk, idx) ((${realtype} *)OPENSSL_sk_value(ossl_check_const_${nametype}_sk_type(sk), (idx)))
+#define sk_${nametype}_new(cmp) ((STACK_OF(${nametype}) *)OPENSSL_sk_new(ossl_check_${nametype}_compfunc_type(cmp)))
+#define sk_${nametype}_new_null() ((STACK_OF(${nametype}) *)OPENSSL_sk_new_null())
+#define sk_${nametype}_new_reserve(cmp, n) ((STACK_OF(${nametype}) *)OPENSSL_sk_new_reserve(ossl_check_${nametype}_compfunc_type(cmp), (n)))
+#define sk_${nametype}_reserve(sk, n) OPENSSL_sk_reserve(ossl_check_${nametype}_sk_type(sk), (n))
+#define sk_${nametype}_free(sk) OPENSSL_sk_free(ossl_check_${nametype}_sk_type(sk))
+#define sk_${nametype}_zero(sk) OPENSSL_sk_zero(ossl_check_${nametype}_sk_type(sk))
+#define sk_${nametype}_delete(sk, i) ((${realtype} *)OPENSSL_sk_delete(ossl_check_${nametype}_sk_type(sk), (i)))
+#define sk_${nametype}_delete_ptr(sk, ptr) ((${realtype} *)OPENSSL_sk_delete_ptr(ossl_check_${nametype}_sk_type(sk), ossl_check_${nametype}_type(ptr)))
+#define sk_${nametype}_push(sk, ptr) OPENSSL_sk_push(ossl_check_${nametype}_sk_type(sk), ossl_check_${nametype}_type(ptr))
+#define sk_${nametype}_unshift(sk, ptr) OPENSSL_sk_unshift(ossl_check_${nametype}_sk_type(sk), ossl_check_${nametype}_type(ptr))
+#define sk_${nametype}_pop(sk) ((${realtype} *)OPENSSL_sk_pop(ossl_check_${nametype}_sk_type(sk)))
+#define sk_${nametype}_shift(sk) ((${realtype} *)OPENSSL_sk_shift(ossl_check_${nametype}_sk_type(sk)))
+#define sk_${nametype}_pop_free(sk, freefunc) OPENSSL_sk_pop_free(ossl_check_${nametype}_sk_type(sk),ossl_check_${nametype}_freefunc_type(freefunc))
+#define sk_${nametype}_insert(sk, ptr, idx) OPENSSL_sk_insert(ossl_check_${nametype}_sk_type(sk), ossl_check_${nametype}_type(ptr), (idx))
+#define sk_${nametype}_set(sk, idx, ptr) ((${realtype} *)OPENSSL_sk_set(ossl_check_${nametype}_sk_type(sk), (idx), ossl_check_${nametype}_type(ptr)))
+#define sk_${nametype}_find(sk, ptr) OPENSSL_sk_find(ossl_check_${nametype}_sk_type(sk), ossl_check_${nametype}_type(ptr))
+#define sk_${nametype}_find_ex(sk, ptr) OPENSSL_sk_find_ex(ossl_check_${nametype}_sk_type(sk), ossl_check_${nametype}_type(ptr))
+#define sk_${nametype}_sort(sk) OPENSSL_sk_sort(ossl_check_${nametype}_sk_type(sk))
+#define sk_${nametype}_is_sorted(sk) OPENSSL_sk_is_sorted(ossl_check_const_${nametype}_sk_type(sk))
+#define sk_${nametype}_dup(sk) ((STACK_OF(${nametype}) *)OPENSSL_sk_dup(ossl_check_const_${nametype}_sk_type(sk)))
+#define sk_${nametype}_deep_copy(sk, copyfunc, freefunc) ((STACK_OF(${nametype}) *)OPENSSL_sk_deep_copy(ossl_check_const_${nametype}_sk_type(sk), ossl_check_${nametype}_copyfunc_type(copyfunc), ossl_check_${nametype}_freefunc_type(freefunc)))
+#define sk_${nametype}_set_cmp_func(sk, cmp) ((sk_${nametype}_compfunc)OPENSSL_sk_set_cmp_func(ossl_check_${nametype}_sk_type(sk), ossl_check_${nametype}_compfunc_type(cmp)))
+END_MACROS
+
+    return $macros;
+}
+
+sub generate_stack_macros {
+    my $type = shift;
+
+    return generate_stack_macros_int($type, $type, $type);
+}
+
+sub generate_const_stack_macros {
+    my $type = shift;
+
+    return generate_stack_macros_int($type, "const $type", $type);
+}
+1;