include/internal/dso.h - third_party/openssl - Git at Google

 /*
  * 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
	/*
	* 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