Make DSO opaque.

This was really easy.

Reviewed-by: Tim Hudson <tjh@openssl.org>

crypto/dso/dso_dl.c

diff --git a/crypto/dso/dso_dl.c b/crypto/dso/dso_dl.c
index 73d7ca3..1d6e12a 100644
--- a/crypto/dso/dso_dl.c
+++ b/crypto/dso/dso_dl.c
@@ -56,10 +56,7 @@
  *
  */
 
-#include <stdio.h>
-#include "internal/cryptlib.h"
-#include <openssl/dso.h>
-#include "internal/dso_conf.h"
+#include "dso_locl.h"
 
 #ifndef DSO_DL
 DSO_METHOD *DSO_METHOD_dl(void)

crypto/dso/dso_dlfcn.c

diff --git a/crypto/dso/dso_dlfcn.c b/crypto/dso/dso_dlfcn.c
index 107abfd..e69daad 100644
--- a/crypto/dso/dso_dlfcn.c
+++ b/crypto/dso/dso_dlfcn.c
@@ -65,10 +65,7 @@
 # define _GNU_SOURCE            /* make sure dladdr is declared */
 #endif
 
-#include <stdio.h>
-#include "internal/cryptlib.h"
-#include <openssl/dso.h>
-#include "internal/dso_conf.h"
+#include "dso_locl.h"
 
 #ifndef DSO_DLFCN
 DSO_METHOD *DSO_METHOD_dlfcn(void)

crypto/dso/dso_err.c

diff --git a/crypto/dso/dso_err.c b/crypto/dso/dso_err.c
index 2a7c821..e47f5cd 100644
--- a/crypto/dso/dso_err.c
+++ b/crypto/dso/dso_err.c
@@ -58,9 +58,7 @@
  * only reason strings will be preserved.
  */
 
-#include <stdio.h>
-#include <openssl/err.h>
-#include <openssl/dso.h>
+#include "dso_locl.h"
 
 /* BEGIN ERROR CODES */
 #ifndef OPENSSL_NO_ERR

crypto/dso/dso_lib.c

diff --git a/crypto/dso/dso_lib.c b/crypto/dso/dso_lib.c
index 3082545..f464fab 100644
--- a/crypto/dso/dso_lib.c
+++ b/crypto/dso/dso_lib.c
@@ -56,10 +56,7 @@
  *
  */
 
-#include <stdio.h>
-#include <openssl/crypto.h>
-#include "internal/cryptlib.h"
-#include <openssl/dso.h>
+#include "dso_locl.h"
 
 static DSO_METHOD *default_DSO_meth = NULL;
 

crypto/dso/dso_locl.h

diff --git a/crypto/dso/dso_locl.h b/crypto/dso/dso_locl.h
new file mode 100644
index 0000000..980448d
--- /dev/null
+++ b/crypto/dso/dso_locl.h
@@ -0,0 +1,108 @@
+/*
+ * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Licensed under the OpenSSL licenses, (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *      https://www.openssl.org/source/license.html
+ * or in the file LICENSE in the source distribution.
+ */
+#include <stdio.h>
+#include "internal/cryptlib.h"
+#include <openssl/dso.h>
+#include "internal/dso_conf.h"
+
+/**********************************************************************/
+/* The low-level handle type used to refer to a loaded shared library */
+
+struct dso_st {
+    DSO_METHOD *meth;
+    /*
+     * Standard dlopen uses a (void *). Win32 uses a HANDLE. VMS doesn't use
+     * anything but will need to cache the filename for use in the dso_bind
+     * handler. All in all, let each method control its own destiny.
+     * "Handles" and such go in a STACK.
+     */
+    STACK_OF(void) *meth_data;
+    int references;
+    int flags;
+    /*
+     * For use by applications etc ... use this for your bits'n'pieces, don't
+     * touch meth_data!
+     */
+    CRYPTO_EX_DATA ex_data;
+    /*
+     * If this callback function pointer is set to non-NULL, then it will be
+     * used in DSO_load() in place of meth->dso_name_converter. NB: This
+     * should normally set using DSO_set_name_converter().
+     */
+    DSO_NAME_CONVERTER_FUNC name_converter;
+    /*
+     * If this callback function pointer is set to non-NULL, then it will be
+     * used in DSO_load() in place of meth->dso_merger. NB: This should
+     * normally set using DSO_set_merger().
+     */
+    DSO_MERGER_FUNC merger;
+    /*
+     * This is populated with (a copy of) the platform-independent filename
+     * used for this DSO.
+     */
+    char *filename;
+    /*
+     * This is populated with (a copy of) the translated filename by which
+     * the DSO was actually loaded. It is NULL iff the DSO is not currently
+     * loaded. NB: This is here because the filename translation process may
+     * involve a callback being invoked more than once not only to convert to
+     * a platform-specific form, but also to try different filenames in the
+     * process of trying to perform a load. As such, this variable can be
+     * used to indicate (a) whether this DSO structure corresponds to a
+     * loaded library or not, and (b) the filename with which it was actually
+     * loaded.
+     */
+    char *loaded_filename;
+    CRYPTO_RWLOCK *lock;
+};
+
+struct dso_meth_st {
+    const char *name;
+    /*
+     * Loads a shared library, NB: new DSO_METHODs must ensure that a
+     * successful load populates the loaded_filename field, and likewise a
+     * successful unload OPENSSL_frees and NULLs it out.
+     */
+    int (*dso_load) (DSO *dso);
+    /* Unloads a shared library */
+    int (*dso_unload) (DSO *dso);
+    /* Binds a variable */
+    void *(*dso_bind_var) (DSO *dso, const char *symname);
+    /*
+     * Binds a function - assumes a return type of DSO_FUNC_TYPE. This should
+     * be cast to the real function prototype by the caller. Platforms that
+     * don't have compatible representations for different prototypes (this
+     * is possible within ANSI C) are highly unlikely to have shared
+     * libraries at all, let alone a DSO_METHOD implemented for them.
+     */
+    DSO_FUNC_TYPE (*dso_bind_func) (DSO *dso, const char *symname);
+    /*
+     * The generic (yuck) "ctrl()" function. NB: Negative return values
+     * (rather than zero) indicate errors.
+     */
+    long (*dso_ctrl) (DSO *dso, int cmd, long larg, void *parg);
+    /*
+     * The default DSO_METHOD-specific function for converting filenames to a
+     * canonical native form.
+     */
+    DSO_NAME_CONVERTER_FUNC dso_name_converter;
+    /*
+     * The default DSO_METHOD-specific function for converting filenames to a
+     * canonical native form.
+     */
+    DSO_MERGER_FUNC dso_merger;
+    /* [De]Initialisation handlers. */
+    int (*init) (DSO *dso);
+    int (*finish) (DSO *dso);
+    /* Return pathname of the module containing location */
+    int (*pathbyaddr) (void *addr, char *path, int sz);
+    /* Perform global symbol lookup, i.e. among *all* modules */
+    void *(*globallookup) (const char *symname);
+};
+

crypto/dso/dso_null.c

diff --git a/crypto/dso/dso_null.c b/crypto/dso/dso_null.c
index fffa592..ed8bcd7 100644
--- a/crypto/dso/dso_null.c
+++ b/crypto/dso/dso_null.c
@@ -61,9 +61,7 @@
  * appropriate support for "shared-libraries".
  */
 
-#include <stdio.h>
-#include "internal/cryptlib.h"
-#include <openssl/dso.h>
+#include "dso_locl.h"
 
 static DSO_METHOD dso_meth_null = {
     "NULL shared library method",
@@ -82,5 +80,5 @@
 
 DSO_METHOD *DSO_METHOD_null(void)
 {
-    return (&dso_meth_null);
+    return &dso_meth_null;
 }

crypto/dso/dso_openssl.c

diff --git a/crypto/dso/dso_openssl.c b/crypto/dso/dso_openssl.c
index 5aa0536..9b0123b 100644
--- a/crypto/dso/dso_openssl.c
+++ b/crypto/dso/dso_openssl.c
@@ -56,9 +56,7 @@
  *
  */
 
-#include <stdio.h>
-#include "internal/cryptlib.h"
-#include <openssl/dso.h>
+#include "dso_locl.h"
 
 /* We just pinch the method from an appropriate "default" method. */
 

crypto/dso/dso_vms.c

diff --git a/crypto/dso/dso_vms.c b/crypto/dso/dso_vms.c
index a36234d..2fd6ffe 100644
--- a/crypto/dso/dso_vms.c
+++ b/crypto/dso/dso_vms.c
@@ -56,11 +56,7 @@
  *
  */
 
-#include <stdio.h>
-#include <string.h>
-#include <errno.h>
-#include "internal/cryptlib.h"
-#include <openssl/dso.h>
+#include "dso_locl.h"
 
 #ifndef OPENSSL_SYS_VMS
 DSO_METHOD *DSO_METHOD_vms(void)
@@ -70,6 +66,7 @@
 #else
 
 # pragma message disable DOLLARID
+# include <errno.h>
 # include <rms.h>
 # include <lib$routines.h>
 # include <stsdef.h>

crypto/dso/dso_win32.c

diff --git a/crypto/dso/dso_win32.c b/crypto/dso/dso_win32.c
index 3d9ee8a..e1d88b1 100644
--- a/crypto/dso/dso_win32.c
+++ b/crypto/dso/dso_win32.c
@@ -56,10 +56,7 @@
  *
  */
 
-#include <stdio.h>
-#include <string.h>
-#include "internal/cryptlib.h"
-#include <openssl/dso.h>
+#include "dso_locl.h"
 
 #if !defined(DSO_WIN32)
 DSO_METHOD *DSO_METHOD_win32(void)