diff options
Diffstat (limited to 'thirdparty/internal/dso.h')
-rw-r--r-- | thirdparty/internal/dso.h | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/thirdparty/internal/dso.h b/thirdparty/internal/dso.h new file mode 100644 index 00000000..160ddb98 --- /dev/null +++ b/thirdparty/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 |