openssl/crypto/dso/dso.h
2008-06-04 11:01:43 +00:00

410 lines
18 KiB
C

/* dso.h -*- mode:C; c-file-style: "eay" -*- */
/* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
* project 2000.
*/
/* ====================================================================
* Copyright (c) 2000 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* licensing@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
#ifndef HEADER_DSO_H
#define HEADER_DSO_H
#include <openssl/crypto.h>
#ifdef __cplusplus
extern "C" {
#endif
/* 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 (more specifically the DSO_METHOD) 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". The
* behaviour can be overriden by setting the name_converter callback in the DSO
* object (using DSO_set_name_converter()). 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
/* The following flag controls the translation of symbol names to upper
* case. This is currently only being implemented for OpenVMS.
*/
#define DSO_FLAG_UPCASE_SYMBOL 0x10
/* 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;
/* 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 independantly 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 independantly 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 *);
typedef 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);
/* I don't think this would actually be used in any circumstances. */
#if 0
/* Unbinds a variable */
int (*dso_unbind_var)(DSO *dso, char *symname, void *symptr);
/* Unbinds a function */
int (*dso_unbind_func)(DSO *dso, char *symname, DSO_FUNC_TYPE symptr);
#endif
/* 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);
} DSO_METHOD;
/**********************************************************************/
/* 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-independant
* 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;
};
DSO * DSO_new(void);
DSO * DSO_new_method(DSO_METHOD *method);
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);
/* This function sets the DSO's name_converter callback. If it is non-NULL,
* then it will be used instead of the associated DSO_METHOD's function. If
* oldcb is non-NULL then it is set to the function pointer value being
* replaced. Return value is non-zero for success. */
int DSO_set_name_converter(DSO *dso, DSO_NAME_CONVERTER_FUNC cb,
DSO_NAME_CONVERTER_FUNC *oldcb);
/* These functions can be used to get/set the platform-independant 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);
/* If the DSO is currently loaded, this returns the filename that it was loaded
* under, otherwise it returns NULL. So it is also useful as a test as to
* whether the DSO is currently loaded. NB: This will not necessarily return
* the same value as DSO_convert_filename(dso, dso->filename), because the
* DSO_METHOD's load function may have tried a variety of filenames (with
* and/or without the aid of the converters) before settling on the one it
* actually loaded. */
const char *DSO_get_loaded_filename(DSO *dso);
void DSO_set_default_method(DSO_METHOD *meth);
DSO_METHOD *DSO_get_default_method(void);
DSO_METHOD *DSO_get_method(DSO *dso);
DSO_METHOD *DSO_set_method(DSO *dso, DSO_METHOD *meth);
/* The all-singing all-dancing load function, you normally pass NULL
* for the first and third parameters. Use DSO_up 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 variable inside a shared library. */
void *DSO_bind_var(DSO *dso, const char *symname);
/* 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 method is defined for all platforms - if a platform has no
* DSO support then this will be the only method! */
DSO_METHOD *DSO_METHOD_null(void);
/* If DSO_DLFCN is defined, the standard dlfcn.h-style functions
* (dlopen, dlclose, dlsym, etc) will be used and incorporated into
* this method. If not, this method will return NULL. */
DSO_METHOD *DSO_METHOD_dlfcn(void);
/* If DSO_DL is defined, the standard dl.h-style functions (shl_load,
* shl_unload, shl_findsym, etc) will be used and incorporated into
* this method. If not, this method will return NULL. */
DSO_METHOD *DSO_METHOD_dl(void);
/* If WIN32 is defined, use DLLs. If not, return NULL. */
DSO_METHOD *DSO_METHOD_win32(void);
/* If VMS is defined, use shared images. If not, return NULL. */
DSO_METHOD *DSO_METHOD_vms(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 charachers [including trailing zero] to
* accomodate 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);
/* 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);
/* If BeOS is defined, use shared images. If not, return NULL. */
DSO_METHOD *DSO_METHOD_beos(void);
/* BEGIN ERROR CODES */
/* The following lines are auto generated by the script mkerr.pl. Any changes
* made after this point may be overwritten when the script is next run.
*/
void ERR_load_DSO_strings(void);
/* Error codes for the DSO functions. */
/* Function codes. */
#define DSO_F_BEOS_BIND_FUNC 144
#define DSO_F_BEOS_BIND_VAR 145
#define DSO_F_BEOS_LOAD 146
#define DSO_F_BEOS_NAME_CONVERTER 147
#define DSO_F_BEOS_UNLOAD 148
#define DSO_F_DLFCN_BIND_FUNC 100
#define DSO_F_DLFCN_BIND_VAR 101
#define DSO_F_DLFCN_LOAD 102
#define DSO_F_DLFCN_MERGER 130
#define DSO_F_DLFCN_NAME_CONVERTER 123
#define DSO_F_DLFCN_UNLOAD 103
#define DSO_F_DL_BIND_FUNC 104
#define DSO_F_DL_BIND_VAR 105
#define DSO_F_DL_LOAD 106
#define DSO_F_DL_MERGER 131
#define DSO_F_DL_NAME_CONVERTER 124
#define DSO_F_DL_UNLOAD 107
#define DSO_F_DSO_BIND_FUNC 108
#define DSO_F_DSO_BIND_VAR 109
#define DSO_F_DSO_CONVERT_FILENAME 126
#define DSO_F_DSO_CTRL 110
#define DSO_F_DSO_FREE 111
#define DSO_F_DSO_GET_FILENAME 127
#define DSO_F_DSO_GET_LOADED_FILENAME 128
#define DSO_F_DSO_GLOBAL_LOOKUP 139
#define DSO_F_DSO_LOAD 112
#define DSO_F_DSO_MERGE 132
#define DSO_F_DSO_NEW_METHOD 113
#define DSO_F_DSO_PATHBYADDR 140
#define DSO_F_DSO_SET_FILENAME 129
#define DSO_F_DSO_SET_NAME_CONVERTER 122
#define DSO_F_DSO_UP_REF 114
#define DSO_F_GLOBAL_LOOKUP_FUNC 138
#define DSO_F_PATHBYADDR 137
#define DSO_F_VMS_BIND_SYM 115
#define DSO_F_VMS_LOAD 116
#define DSO_F_VMS_MERGER 133
#define DSO_F_VMS_UNLOAD 117
#define DSO_F_WIN32_BIND_FUNC 118
#define DSO_F_WIN32_BIND_VAR 119
#define DSO_F_WIN32_GLOBALLOOKUP 142
#define DSO_F_WIN32_GLOBALLOOKUP_FUNC 143
#define DSO_F_WIN32_JOINER 135
#define DSO_F_WIN32_LOAD 120
#define DSO_F_WIN32_MERGER 134
#define DSO_F_WIN32_NAME_CONVERTER 125
#define DSO_F_WIN32_PATHBYADDR 141
#define DSO_F_WIN32_SPLITTER 136
#define DSO_F_WIN32_UNLOAD 121
/* Reason codes. */
#define DSO_R_CTRL_FAILED 100
#define DSO_R_DSO_ALREADY_LOADED 110
#define DSO_R_EMPTY_FILE_STRUCTURE 113
#define DSO_R_FAILURE 114
#define DSO_R_FILENAME_TOO_BIG 101
#define DSO_R_FINISH_FAILED 102
#define DSO_R_INCORRECT_FILE_SYNTAX 115
#define DSO_R_LOAD_FAILED 103
#define DSO_R_NAME_TRANSLATION_FAILED 109
#define DSO_R_NO_FILENAME 111
#define DSO_R_NO_FILE_SPECIFICATION 116
#define DSO_R_NULL_HANDLE 104
#define DSO_R_SET_FILENAME_FAILED 112
#define DSO_R_STACK_ERROR 105
#define DSO_R_SYM_FAILURE 106
#define DSO_R_UNLOAD_FAILED 107
#define DSO_R_UNSUPPORTED 108
#ifdef __cplusplus
}
#endif
#endif