1 files changed, 164 insertions, 0 deletions
diff --git a/include/internal/dso.h b/include/internal/dso.h
new file mode 100644
index 00000000..160ddb98
--- /dev/null
+++ b/include/internal/dso.h
@@ -0,0 +1,164 @@
+/*
+ * Copyright 2000-2021 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
+ */
+
+#ifndef OSSL_INTERNAL_DSO_H
+# define OSSL_INTERNAL_DSO_H
+# pragma once
+
+# include <openssl/crypto.h>
+# include "internal/dsoerr.h"
+
+/* These values are used as commands to DSO_ctrl() */
+# define DSO_CTRL_GET_FLAGS      1
+# define DSO_CTRL_SET_FLAGS      2
+# define DSO_CTRL_OR_FLAGS       3
+
+/*
+ * By default, DSO_load() will translate the provided filename into a form
+ * typical for the platform using the dso_name_converter function of the
+ * method. Eg. win32 will transform "blah" into "blah.dll", and dlfcn will
+ * transform it into "libblah.so". This callback could even utilise the
+ * DSO_METHOD's converter too if it only wants to override behaviour for
+ * one or two possible DSO methods. However, the following flag can be
+ * set in a DSO to prevent *any* native name-translation at all - eg. if
+ * the caller has prompted the user for a path to a driver library so the
+ * filename should be interpreted as-is.
+ */
+# define DSO_FLAG_NO_NAME_TRANSLATION            0x01
+/*
+ * An extra flag to give if only the extension should be added as
+ * translation.  This is obviously only of importance on Unix and other
+ * operating systems where the translation also may prefix the name with
+ * something, like 'lib', and ignored everywhere else. This flag is also
+ * ignored if DSO_FLAG_NO_NAME_TRANSLATION is used at the same time.
+ */
+# define DSO_FLAG_NAME_TRANSLATION_EXT_ONLY      0x02
+
+/*
+ * Don't unload the DSO when we call DSO_free()
+ */
+# define DSO_FLAG_NO_UNLOAD_ON_FREE              0x04
+
+/*
+ * This flag loads the library with public symbols. Meaning: The exported
+ * symbols of this library are public to all libraries loaded after this
+ * library. At the moment only implemented in unix.
+ */
+# define DSO_FLAG_GLOBAL_SYMBOLS                 0x20
+
+typedef void (*DSO_FUNC_TYPE) (void);
+
+typedef struct dso_st DSO;
+typedef struct dso_meth_st DSO_METHOD;
+
+/*
+ * The function prototype used for method functions (or caller-provided
+ * callbacks) that transform filenames. They are passed a DSO structure
+ * pointer (or NULL if they are to be used independently of a DSO object) and
+ * a filename to transform. They should either return NULL (if there is an
+ * error condition) or a newly allocated string containing the transformed
+ * form that the caller will need to free with OPENSSL_free() when done.
+ */
+typedef char *(*DSO_NAME_CONVERTER_FUNC)(DSO *, const char *);
+/*
+ * The function prototype used for method functions (or caller-provided
+ * callbacks) that merge two file specifications. They are passed a DSO
+ * structure pointer (or NULL if they are to be used independently of a DSO
+ * object) and two file specifications to merge. They should either return
+ * NULL (if there is an error condition) or a newly allocated string
+ * containing the result of merging that the caller will need to free with
+ * OPENSSL_free() when done. Here, merging means that bits and pieces are
+ * taken from each of the file specifications and added together in whatever
+ * fashion that is sensible for the DSO method in question.  The only rule
+ * that really applies is that if the two specification contain pieces of the
+ * same type, the copy from the first string takes priority.  One could see
+ * it as the first specification is the one given by the user and the second
+ * being a bunch of defaults to add on if they're missing in the first.
+ */
+typedef char *(*DSO_MERGER_FUNC)(DSO *, const char *, const char *);
+
+DSO *DSO_new(void);
+int DSO_free(DSO *dso);
+int DSO_flags(DSO *dso);
+int DSO_up_ref(DSO *dso);
+long DSO_ctrl(DSO *dso, int cmd, long larg, void *parg);
+
+/*
+ * These functions can be used to get/set the platform-independent filename
+ * used for a DSO. NB: set will fail if the DSO is already loaded.
+ */
+const char *DSO_get_filename(DSO *dso);
+int DSO_set_filename(DSO *dso, const char *filename);
+/*
+ * This function will invoke the DSO's name_converter callback to translate a
+ * filename, or if the callback isn't set it will instead use the DSO_METHOD's
+ * converter. If "filename" is NULL, the "filename" in the DSO itself will be
+ * used. If the DSO_FLAG_NO_NAME_TRANSLATION flag is set, then the filename is
+ * simply duplicated. NB: This function is usually called from within a
+ * DSO_METHOD during the processing of a DSO_load() call, and is exposed so
+ * that caller-created DSO_METHODs can do the same thing. A non-NULL return
+ * value will need to be OPENSSL_free()'d.
+ */
+char *DSO_convert_filename(DSO *dso, const char *filename);
+/*
+ * This function will invoke the DSO's merger callback to merge two file
+ * specifications, or if the callback isn't set it will instead use the
+ * DSO_METHOD's merger.  A non-NULL return value will need to be
+ * OPENSSL_free()'d.
+ */
+char *DSO_merge(DSO *dso, const char *filespec1, const char *filespec2);
+
+/*
+ * The all-singing all-dancing load function, you normally pass NULL for the
+ * first and third parameters. Use DSO_up_ref and DSO_free for subsequent
+ * reference count handling. Any flags passed in will be set in the
+ * constructed DSO after its init() function but before the load operation.
+ * If 'dso' is non-NULL, 'flags' is ignored.
+ */
+DSO *DSO_load(DSO *dso, const char *filename, DSO_METHOD *meth, int flags);
+
+/* This function binds to a function inside a shared library. */
+DSO_FUNC_TYPE DSO_bind_func(DSO *dso, const char *symname);
+
+/*
+ * This method is the default, but will beg, borrow, or steal whatever method
+ * should be the default on any particular platform (including
+ * DSO_METH_null() if necessary).
+ */
+DSO_METHOD *DSO_METHOD_openssl(void);
+
+/*
+ * This function writes null-terminated pathname of DSO module containing
+ * 'addr' into 'sz' large caller-provided 'path' and returns the number of
+ * characters [including trailing zero] written to it. If 'sz' is 0 or
+ * negative, 'path' is ignored and required amount of characters [including
+ * trailing zero] to accommodate pathname is returned. If 'addr' is NULL, then
+ * pathname of cryptolib itself is returned. Negative or zero return value
+ * denotes error.
+ */
+int DSO_pathbyaddr(void *addr, char *path, int sz);
+
+/*
+ * Like DSO_pathbyaddr() but instead returns a handle to the DSO for the symbol
+ * or NULL on error.
+ */
+DSO *DSO_dsobyaddr(void *addr, int flags);
+
+/*
+ * This function should be used with caution! It looks up symbols in *all*
+ * loaded modules and if module gets unloaded by somebody else attempt to
+ * dereference the pointer is doomed to have fatal consequences. Primary
+ * usage for this function is to probe *core* system functionality, e.g.
+ * check if getnameinfo(3) is available at run-time without bothering about
+ * OS-specific details such as libc.so.versioning or where does it actually
+ * reside: in libc itself or libsocket.
+ */
+void *DSO_global_lookup(const char *name);
+
+#endif