xref: /openbsd-src/lib/libcrypto/engine/engine.h (revision ff0e7be1ebbcc809ea8ad2b6dafe215824da9e46)
1 /* $OpenBSD: engine.h,v 1.38 2023/04/18 09:10:44 tb Exp $ */
2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
3  * project 2000.
4  */
5 /* ====================================================================
6  * Copyright (c) 1999-2004 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    licensing@OpenSSL.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58 /* ====================================================================
59  * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
60  * ECDH support in OpenSSL originally developed by
61  * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
62  */
63 
64 #ifndef HEADER_ENGINE_H
65 #define HEADER_ENGINE_H
66 
67 #include <openssl/opensslconf.h>
68 
69 #ifdef OPENSSL_NO_ENGINE
70 #error ENGINE is disabled.
71 #endif
72 
73 #include <openssl/bn.h>
74 #ifndef OPENSSL_NO_DH
75 #include <openssl/dh.h>
76 #endif
77 #ifndef OPENSSL_NO_DSA
78 #include <openssl/dsa.h>
79 #endif
80 #ifndef OPENSSL_NO_EC
81 #include <openssl/ec.h>
82 #endif
83 #ifndef OPENSSL_NO_ECDH
84 #include <openssl/ecdh.h>
85 #endif
86 #ifndef OPENSSL_NO_ECDSA
87 #include <openssl/ecdsa.h>
88 #endif
89 #include <openssl/err.h>
90 #ifndef OPENSSL_NO_RSA
91 #include <openssl/rsa.h>
92 #endif
93 #include <openssl/ui.h>
94 #include <openssl/x509.h>
95 
96 #include <openssl/ossl_typ.h>
97 
98 #ifdef  __cplusplus
99 extern "C" {
100 #endif
101 
102 /* These flags are used to control combinations of algorithm (methods)
103  * by bitwise "OR"ing. */
104 #define ENGINE_METHOD_RSA		(unsigned int)0x0001
105 #define ENGINE_METHOD_DSA		(unsigned int)0x0002
106 #define ENGINE_METHOD_DH		(unsigned int)0x0004
107 #define ENGINE_METHOD_RAND		(unsigned int)0x0008
108 #define ENGINE_METHOD_ECDH		(unsigned int)0x0010
109 #define ENGINE_METHOD_ECDSA		(unsigned int)0x0020
110 #define ENGINE_METHOD_CIPHERS		(unsigned int)0x0040
111 #define ENGINE_METHOD_DIGESTS		(unsigned int)0x0080
112 #define ENGINE_METHOD_STORE		(unsigned int)0x0100
113 #define ENGINE_METHOD_PKEY_METHS	(unsigned int)0x0200
114 #define ENGINE_METHOD_PKEY_ASN1_METHS	(unsigned int)0x0400
115 #define ENGINE_METHOD_EC		(unsigned int)0x0800
116 /* Obvious all-or-nothing cases. */
117 #define ENGINE_METHOD_ALL		(unsigned int)0xFFFF
118 #define ENGINE_METHOD_NONE		(unsigned int)0x0000
119 
120 /* This(ese) flag(s) controls behaviour of the ENGINE_TABLE mechanism used
121  * internally to control registration of ENGINE implementations, and can be set
122  * by ENGINE_set_table_flags(). The "NOINIT" flag prevents attempts to
123  * initialise registered ENGINEs if they are not already initialised. */
124 #define ENGINE_TABLE_FLAG_NOINIT	(unsigned int)0x0001
125 
126 /* ENGINE flags that can be set by ENGINE_set_flags(). */
127 /* #define ENGINE_FLAGS_MALLOCED	0x0001 */ /* Not used */
128 
129 /* This flag is for ENGINEs that wish to handle the various 'CMD'-related
130  * control commands on their own. Without this flag, ENGINE_ctrl() handles these
131  * control commands on behalf of the ENGINE using their "cmd_defns" data. */
132 #define ENGINE_FLAGS_MANUAL_CMD_CTRL	(int)0x0002
133 
134 /* This flag is for ENGINEs who return new duplicate structures when found via
135  * "ENGINE_by_id()". When an ENGINE must store state (eg. if ENGINE_ctrl()
136  * commands are called in sequence as part of some stateful process like
137  * key-generation setup and execution), it can set this flag - then each attempt
138  * to obtain the ENGINE will result in it being copied into a new structure.
139  * Normally, ENGINEs don't declare this flag so ENGINE_by_id() just increments
140  * the existing ENGINE's structural reference count. */
141 #define ENGINE_FLAGS_BY_ID_COPY		(int)0x0004
142 
143 /* This flag if for an ENGINE that does not want its methods registered as
144  * part of ENGINE_register_all_complete() for example if the methods are
145  * not usable as default methods.
146  */
147 
148 #define ENGINE_FLAGS_NO_REGISTER_ALL	(int)0x0008
149 
150 /* ENGINEs can support their own command types, and these flags are used in
151  * ENGINE_CTRL_GET_CMD_FLAGS to indicate to the caller what kind of input each
152  * command expects. Currently only numeric and string input is supported. If a
153  * control command supports none of the _NUMERIC, _STRING, or _NO_INPUT options,
154  * then it is regarded as an "internal" control command - and not for use in
155  * config setting situations. As such, they're not available to the
156  * ENGINE_ctrl_cmd_string() function, only raw ENGINE_ctrl() access. Changes to
157  * this list of 'command types' should be reflected carefully in
158  * ENGINE_cmd_is_executable() and ENGINE_ctrl_cmd_string(). */
159 
160 /* accepts a 'long' input value (3rd parameter to ENGINE_ctrl) */
161 #define ENGINE_CMD_FLAG_NUMERIC		(unsigned int)0x0001
162 /* accepts string input (cast from 'void*' to 'const char *', 4th parameter to
163  * ENGINE_ctrl) */
164 #define ENGINE_CMD_FLAG_STRING		(unsigned int)0x0002
165 /* Indicates that the control command takes *no* input. Ie. the control command
166  * is unparameterised. */
167 #define ENGINE_CMD_FLAG_NO_INPUT	(unsigned int)0x0004
168 /* Indicates that the control command is internal. This control command won't
169  * be shown in any output, and is only usable through the ENGINE_ctrl_cmd()
170  * function. */
171 #define ENGINE_CMD_FLAG_INTERNAL	(unsigned int)0x0008
172 
173 /* NB: These 3 control commands are deprecated and should not be used. ENGINEs
174  * relying on these commands should compile conditional support for
175  * compatibility (eg. if these symbols are defined) but should also migrate the
176  * same functionality to their own ENGINE-specific control functions that can be
177  * "discovered" by calling applications. The fact these control commands
178  * wouldn't be "executable" (ie. usable by text-based config) doesn't change the
179  * fact that application code can find and use them without requiring per-ENGINE
180  * hacking. */
181 
182 /* These flags are used to tell the ctrl function what should be done.
183  * All command numbers are shared between all engines, even if some don't
184  * make sense to some engines.  In such a case, they do nothing but return
185  * the error ENGINE_R_CTRL_COMMAND_NOT_IMPLEMENTED. */
186 #define ENGINE_CTRL_SET_LOGSTREAM		1
187 #define ENGINE_CTRL_SET_PASSWORD_CALLBACK	2
188 #define ENGINE_CTRL_HUP				3 /* Close and reinitialise any
189 						     handles/connections etc. */
190 #define ENGINE_CTRL_SET_USER_INTERFACE          4 /* Alternative to callback */
191 #define ENGINE_CTRL_SET_CALLBACK_DATA           5 /* User-specific data, used
192 						     when calling the password
193 						     callback and the user
194 						     interface */
195 #define ENGINE_CTRL_LOAD_CONFIGURATION		6 /* Load a configuration, given
196 						     a string that represents a
197 						     file name or so */
198 #define ENGINE_CTRL_LOAD_SECTION		7 /* Load data from a given
199 						     section in the already loaded
200 						     configuration */
201 
202 /* These control commands allow an application to deal with an arbitrary engine
203  * in a dynamic way. Warn: Negative return values indicate errors FOR THESE
204  * COMMANDS because zero is used to indicate 'end-of-list'. Other commands,
205  * including ENGINE-specific command types, return zero for an error.
206  *
207  * An ENGINE can choose to implement these ctrl functions, and can internally
208  * manage things however it chooses - it does so by setting the
209  * ENGINE_FLAGS_MANUAL_CMD_CTRL flag (using ENGINE_set_flags()). Otherwise the
210  * ENGINE_ctrl() code handles this on the ENGINE's behalf using the cmd_defns
211  * data (set using ENGINE_set_cmd_defns()). This means an ENGINE's ctrl()
212  * handler need only implement its own commands - the above "meta" commands will
213  * be taken care of. */
214 
215 /* Returns non-zero if the supplied ENGINE has a ctrl() handler. If "not", then
216  * all the remaining control commands will return failure, so it is worth
217  * checking this first if the caller is trying to "discover" the engine's
218  * capabilities and doesn't want errors generated unnecessarily. */
219 #define ENGINE_CTRL_HAS_CTRL_FUNCTION		10
220 /* Returns a positive command number for the first command supported by the
221  * engine. Returns zero if no ctrl commands are supported. */
222 #define ENGINE_CTRL_GET_FIRST_CMD_TYPE		11
223 /* The 'long' argument specifies a command implemented by the engine, and the
224  * return value is the next command supported, or zero if there are no more. */
225 #define ENGINE_CTRL_GET_NEXT_CMD_TYPE		12
226 /* The 'void*' argument is a command name (cast from 'const char *'), and the
227  * return value is the command that corresponds to it. */
228 #define ENGINE_CTRL_GET_CMD_FROM_NAME		13
229 /* The next two allow a command to be converted into its corresponding string
230  * form. In each case, the 'long' argument supplies the command. In the NAME_LEN
231  * case, the return value is the length of the command name (not counting a
232  * trailing EOL). In the NAME case, the 'void*' argument must be a string buffer
233  * large enough, and it will be populated with the name of the command (WITH a
234  * trailing EOL). */
235 #define ENGINE_CTRL_GET_NAME_LEN_FROM_CMD	14
236 #define ENGINE_CTRL_GET_NAME_FROM_CMD		15
237 /* The next two are similar but give a "short description" of a command. */
238 #define ENGINE_CTRL_GET_DESC_LEN_FROM_CMD	16
239 #define ENGINE_CTRL_GET_DESC_FROM_CMD		17
240 /* With this command, the return value is the OR'd combination of
241  * ENGINE_CMD_FLAG_*** values that indicate what kind of input a given
242  * engine-specific ctrl command expects. */
243 #define ENGINE_CTRL_GET_CMD_FLAGS		18
244 
245 /* ENGINE implementations should start the numbering of their own control
246  * commands from this value. (ie. ENGINE_CMD_BASE, ENGINE_CMD_BASE + 1, etc). */
247 #define ENGINE_CMD_BASE				200
248 
249 /* If an ENGINE supports its own specific control commands and wishes the
250  * framework to handle the above 'ENGINE_CMD_***'-manipulation commands on its
251  * behalf, it should supply a null-terminated array of ENGINE_CMD_DEFN entries
252  * to ENGINE_set_cmd_defns(). It should also implement a ctrl() handler that
253  * supports the stated commands (ie. the "cmd_num" entries as described by the
254  * array). NB: The array must be ordered in increasing order of cmd_num.
255  * "null-terminated" means that the last ENGINE_CMD_DEFN element has cmd_num set
256  * to zero and/or cmd_name set to NULL. */
257 typedef struct ENGINE_CMD_DEFN_st {
258 	unsigned int cmd_num; /* The command number */
259 	const char *cmd_name; /* The command name itself */
260 	const char *cmd_desc; /* A short description of the command */
261 	unsigned int cmd_flags; /* The input the command expects */
262 } ENGINE_CMD_DEFN;
263 
264 /* Generic function pointer */
265 typedef int (*ENGINE_GEN_FUNC_PTR)(void);
266 /* Generic function pointer taking no arguments */
267 typedef int (*ENGINE_GEN_INT_FUNC_PTR)(ENGINE *);
268 /* Specific control function pointer */
269 typedef int (*ENGINE_CTRL_FUNC_PTR)(ENGINE *, int, long, void *,
270     void (*f)(void));
271 /* Generic load_key function pointer */
272 typedef EVP_PKEY * (*ENGINE_LOAD_KEY_PTR)(ENGINE *, const char *,
273     UI_METHOD *ui_method, void *callback_data);
274 typedef int (*ENGINE_SSL_CLIENT_CERT_PTR)(ENGINE *, SSL *ssl,
275     STACK_OF(X509_NAME) *ca_dn, X509 **pcert, EVP_PKEY **pkey,
276     STACK_OF(X509) **pother, UI_METHOD *ui_method, void *callback_data);
277 
278 /* These callback types are for an ENGINE's handler for cipher and digest logic.
279  * These handlers have these prototypes;
280  *   int foo(ENGINE *e, const EVP_CIPHER **cipher, const int **nids, int nid);
281  *   int foo(ENGINE *e, const EVP_MD **digest, const int **nids, int nid);
282  * Looking at how to implement these handlers in the case of cipher support, if
283  * the framework wants the EVP_CIPHER for 'nid', it will call;
284  *   foo(e, &p_evp_cipher, NULL, nid);    (return zero for failure)
285  * If the framework wants a list of supported 'nid's, it will call;
286  *   foo(e, NULL, &p_nids, 0); (returns number of 'nids' or -1 for error)
287  */
288 /* Returns to a pointer to the array of supported cipher 'nid's. If the second
289  * parameter is non-NULL it is set to the size of the returned array. */
290 typedef int (*ENGINE_CIPHERS_PTR)(ENGINE *, const EVP_CIPHER **,
291     const int **, int);
292 typedef int (*ENGINE_DIGESTS_PTR)(ENGINE *, const EVP_MD **, const int **, int);
293 typedef int (*ENGINE_PKEY_METHS_PTR)(ENGINE *, EVP_PKEY_METHOD **,
294     const int **, int);
295 typedef int (*ENGINE_PKEY_ASN1_METHS_PTR)(ENGINE *, EVP_PKEY_ASN1_METHOD **,
296     const int **, int);
297 
298 /* STRUCTURE functions ... all of these functions deal with pointers to ENGINE
299  * structures where the pointers have a "structural reference". This means that
300  * their reference is to allowed access to the structure but it does not imply
301  * that the structure is functional. To simply increment or decrement the
302  * structural reference count, use ENGINE_by_id and ENGINE_free. NB: This is not
303  * required when iterating using ENGINE_get_next as it will automatically
304  * decrement the structural reference count of the "current" ENGINE and
305  * increment the structural reference count of the ENGINE it returns (unless it
306  * is NULL). */
307 
308 /* Get the first/last "ENGINE" type available. */
309 ENGINE *ENGINE_get_first(void);
310 ENGINE *ENGINE_get_last(void);
311 /* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
312 ENGINE *ENGINE_get_next(ENGINE *e);
313 ENGINE *ENGINE_get_prev(ENGINE *e);
314 /* Add another "ENGINE" type into the array. */
315 int ENGINE_add(ENGINE *e);
316 /* Remove an existing "ENGINE" type from the array. */
317 int ENGINE_remove(ENGINE *e);
318 /* Retrieve an engine from the list by its unique "id" value. */
319 ENGINE *ENGINE_by_id(const char *id);
320 /* Add all the built-in engines. */
321 void ENGINE_load_openssl(void);
322 void ENGINE_load_dynamic(void);
323 #ifndef OPENSSL_NO_STATIC_ENGINE
324 void ENGINE_load_padlock(void);
325 #endif
326 void ENGINE_load_builtin_engines(void);
327 
328 /* Get and set global flags (ENGINE_TABLE_FLAG_***) for the implementation
329  * "registry" handling. */
330 unsigned int ENGINE_get_table_flags(void);
331 void ENGINE_set_table_flags(unsigned int flags);
332 
333 /* Manage registration of ENGINEs per "table". For each type, there are 3
334  * functions;
335  *   ENGINE_register_***(e) - registers the implementation from 'e' (if it has one)
336  *   ENGINE_unregister_***(e) - unregister the implementation from 'e'
337  *   ENGINE_register_all_***() - call ENGINE_register_***() for each 'e' in the list
338  * Cleanup is automatically registered from each table when required, so
339  * ENGINE_cleanup() will reverse any "register" operations. */
340 
341 int ENGINE_register_RSA(ENGINE *e);
342 void ENGINE_unregister_RSA(ENGINE *e);
343 void ENGINE_register_all_RSA(void);
344 
345 int ENGINE_register_DSA(ENGINE *e);
346 void ENGINE_unregister_DSA(ENGINE *e);
347 void ENGINE_register_all_DSA(void);
348 
349 int ENGINE_register_ECDH(ENGINE *e);
350 void ENGINE_unregister_ECDH(ENGINE *e);
351 void ENGINE_register_all_ECDH(void);
352 
353 int ENGINE_register_ECDSA(ENGINE *e);
354 void ENGINE_unregister_ECDSA(ENGINE *e);
355 void ENGINE_register_all_ECDSA(void);
356 
357 int ENGINE_register_EC(ENGINE *e);
358 void ENGINE_unregister_EC(ENGINE *e);
359 void ENGINE_register_all_EC(void);
360 
361 int ENGINE_register_DH(ENGINE *e);
362 void ENGINE_unregister_DH(ENGINE *e);
363 void ENGINE_register_all_DH(void);
364 
365 int ENGINE_register_RAND(ENGINE *e);
366 void ENGINE_unregister_RAND(ENGINE *e);
367 void ENGINE_register_all_RAND(void);
368 
369 int ENGINE_register_STORE(ENGINE *e);
370 void ENGINE_unregister_STORE(ENGINE *e);
371 void ENGINE_register_all_STORE(void);
372 
373 int ENGINE_register_ciphers(ENGINE *e);
374 void ENGINE_unregister_ciphers(ENGINE *e);
375 void ENGINE_register_all_ciphers(void);
376 
377 int ENGINE_register_digests(ENGINE *e);
378 void ENGINE_unregister_digests(ENGINE *e);
379 void ENGINE_register_all_digests(void);
380 
381 int ENGINE_register_pkey_meths(ENGINE *e);
382 void ENGINE_unregister_pkey_meths(ENGINE *e);
383 void ENGINE_register_all_pkey_meths(void);
384 
385 int ENGINE_register_pkey_asn1_meths(ENGINE *e);
386 void ENGINE_unregister_pkey_asn1_meths(ENGINE *e);
387 void ENGINE_register_all_pkey_asn1_meths(void);
388 
389 /* These functions register all support from the above categories. Note, use of
390  * these functions can result in static linkage of code your application may not
391  * need. If you only need a subset of functionality, consider using more
392  * selective initialisation. */
393 int ENGINE_register_complete(ENGINE *e);
394 int ENGINE_register_all_complete(void);
395 
396 /* Send parametrised control commands to the engine. The possibilities to send
397  * down an integer, a pointer to data or a function pointer are provided. Any of
398  * the parameters may or may not be NULL, depending on the command number. In
399  * actuality, this function only requires a structural (rather than functional)
400  * reference to an engine, but many control commands may require the engine be
401  * functional. The caller should be aware of trying commands that require an
402  * operational ENGINE, and only use functional references in such situations. */
403 int ENGINE_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void));
404 
405 /* This function tests if an ENGINE-specific command is usable as a "setting".
406  * Eg. in an application's config file that gets processed through
407  * ENGINE_ctrl_cmd_string(). If this returns zero, it is not available to
408  * ENGINE_ctrl_cmd_string(), only ENGINE_ctrl(). */
409 int ENGINE_cmd_is_executable(ENGINE *e, int cmd);
410 
411 /* This function works like ENGINE_ctrl() with the exception of taking a
412  * command name instead of a command number, and can handle optional commands.
413  * See the comment on ENGINE_ctrl_cmd_string() for an explanation on how to
414  * use the cmd_name and cmd_optional. */
415 int ENGINE_ctrl_cmd(ENGINE *e, const char *cmd_name,
416     long i, void *p, void (*f)(void), int cmd_optional);
417 
418 /* This function passes a command-name and argument to an ENGINE. The cmd_name
419  * is converted to a command number and the control command is called using
420  * 'arg' as an argument (unless the ENGINE doesn't support such a command, in
421  * which case no control command is called). The command is checked for input
422  * flags, and if necessary the argument will be converted to a numeric value. If
423  * cmd_optional is non-zero, then if the ENGINE doesn't support the given
424  * cmd_name the return value will be success anyway. This function is intended
425  * for applications to use so that users (or config files) can supply
426  * engine-specific config data to the ENGINE at run-time to control behaviour of
427  * specific engines. As such, it shouldn't be used for calling ENGINE_ctrl()
428  * functions that return data, deal with binary data, or that are otherwise
429  * supposed to be used directly through ENGINE_ctrl() in application code. Any
430  * "return" data from an ENGINE_ctrl() operation in this function will be lost -
431  * the return value is interpreted as failure if the return value is zero,
432  * success otherwise, and this function returns a boolean value as a result. In
433  * other words, vendors of 'ENGINE'-enabled devices should write ENGINE
434  * implementations with parameterisations that work in this scheme, so that
435  * compliant ENGINE-based applications can work consistently with the same
436  * configuration for the same ENGINE-enabled devices, across applications. */
437 int ENGINE_ctrl_cmd_string(ENGINE *e, const char *cmd_name, const char *arg,
438     int cmd_optional);
439 
440 /* These functions are useful for manufacturing new ENGINE structures. They
441  * don't address reference counting at all - one uses them to populate an ENGINE
442  * structure with personalised implementations of things prior to using it
443  * directly or adding it to the builtin ENGINE list in OpenSSL. These are also
444  * here so that the ENGINE structure doesn't have to be exposed and break binary
445  * compatibility! */
446 ENGINE *ENGINE_new(void);
447 int ENGINE_free(ENGINE *e);
448 int ENGINE_up_ref(ENGINE *e);
449 int ENGINE_set_id(ENGINE *e, const char *id);
450 int ENGINE_set_name(ENGINE *e, const char *name);
451 int ENGINE_set_RSA(ENGINE *e, const RSA_METHOD *rsa_meth);
452 int ENGINE_set_DSA(ENGINE *e, const DSA_METHOD *dsa_meth);
453 int ENGINE_set_ECDH(ENGINE *e, const ECDH_METHOD *ecdh_meth);
454 int ENGINE_set_ECDSA(ENGINE *e, const ECDSA_METHOD *ecdsa_meth);
455 int ENGINE_set_EC(ENGINE *e, const EC_KEY_METHOD *ec_meth);
456 int ENGINE_set_DH(ENGINE *e, const DH_METHOD *dh_meth);
457 int ENGINE_set_RAND(ENGINE *e, const RAND_METHOD *rand_meth);
458 int ENGINE_set_STORE(ENGINE *e, const STORE_METHOD *store_meth);
459 int ENGINE_set_destroy_function(ENGINE *e, ENGINE_GEN_INT_FUNC_PTR destroy_f);
460 int ENGINE_set_init_function(ENGINE *e, ENGINE_GEN_INT_FUNC_PTR init_f);
461 int ENGINE_set_finish_function(ENGINE *e, ENGINE_GEN_INT_FUNC_PTR finish_f);
462 int ENGINE_set_ctrl_function(ENGINE *e, ENGINE_CTRL_FUNC_PTR ctrl_f);
463 int ENGINE_set_load_privkey_function(ENGINE *e, ENGINE_LOAD_KEY_PTR loadpriv_f);
464 int ENGINE_set_load_pubkey_function(ENGINE *e, ENGINE_LOAD_KEY_PTR loadpub_f);
465 int ENGINE_set_load_ssl_client_cert_function(ENGINE *e,
466     ENGINE_SSL_CLIENT_CERT_PTR loadssl_f);
467 int ENGINE_set_ciphers(ENGINE *e, ENGINE_CIPHERS_PTR f);
468 int ENGINE_set_digests(ENGINE *e, ENGINE_DIGESTS_PTR f);
469 int ENGINE_set_pkey_meths(ENGINE *e, ENGINE_PKEY_METHS_PTR f);
470 int ENGINE_set_pkey_asn1_meths(ENGINE *e, ENGINE_PKEY_ASN1_METHS_PTR f);
471 int ENGINE_set_flags(ENGINE *e, int flags);
472 int ENGINE_set_cmd_defns(ENGINE *e, const ENGINE_CMD_DEFN *defns);
473 /* These functions allow control over any per-structure ENGINE data. */
474 int ENGINE_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
475     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
476 int ENGINE_set_ex_data(ENGINE *e, int idx, void *arg);
477 void *ENGINE_get_ex_data(const ENGINE *e, int idx);
478 
479 /* This function cleans up anything that needs it. Eg. the ENGINE_add() function
480  * automatically ensures the list cleanup function is registered to be called
481  * from ENGINE_cleanup(). Similarly, all ENGINE_register_*** functions ensure
482  * ENGINE_cleanup() will clean up after them. */
483 void ENGINE_cleanup(void);
484 
485 /* These return values from within the ENGINE structure. These can be useful
486  * with functional references as well as structural references - it depends
487  * which you obtained. Using the result for functional purposes if you only
488  * obtained a structural reference may be problematic! */
489 const char *ENGINE_get_id(const ENGINE *e);
490 const char *ENGINE_get_name(const ENGINE *e);
491 const RSA_METHOD *ENGINE_get_RSA(const ENGINE *e);
492 const DSA_METHOD *ENGINE_get_DSA(const ENGINE *e);
493 const ECDH_METHOD *ENGINE_get_ECDH(const ENGINE *e);
494 const ECDSA_METHOD *ENGINE_get_ECDSA(const ENGINE *e);
495 const EC_KEY_METHOD *ENGINE_get_EC(const ENGINE *e);
496 const DH_METHOD *ENGINE_get_DH(const ENGINE *e);
497 const RAND_METHOD *ENGINE_get_RAND(const ENGINE *e);
498 const STORE_METHOD *ENGINE_get_STORE(const ENGINE *e);
499 ENGINE_GEN_INT_FUNC_PTR ENGINE_get_destroy_function(const ENGINE *e);
500 ENGINE_GEN_INT_FUNC_PTR ENGINE_get_init_function(const ENGINE *e);
501 ENGINE_GEN_INT_FUNC_PTR ENGINE_get_finish_function(const ENGINE *e);
502 ENGINE_CTRL_FUNC_PTR ENGINE_get_ctrl_function(const ENGINE *e);
503 ENGINE_LOAD_KEY_PTR ENGINE_get_load_privkey_function(const ENGINE *e);
504 ENGINE_LOAD_KEY_PTR ENGINE_get_load_pubkey_function(const ENGINE *e);
505 ENGINE_SSL_CLIENT_CERT_PTR ENGINE_get_ssl_client_cert_function(const ENGINE *e);
506 ENGINE_CIPHERS_PTR ENGINE_get_ciphers(const ENGINE *e);
507 ENGINE_DIGESTS_PTR ENGINE_get_digests(const ENGINE *e);
508 ENGINE_PKEY_METHS_PTR ENGINE_get_pkey_meths(const ENGINE *e);
509 ENGINE_PKEY_ASN1_METHS_PTR ENGINE_get_pkey_asn1_meths(const ENGINE *e);
510 const EVP_CIPHER *ENGINE_get_cipher(ENGINE *e, int nid);
511 const EVP_MD *ENGINE_get_digest(ENGINE *e, int nid);
512 const EVP_PKEY_METHOD *ENGINE_get_pkey_meth(ENGINE *e, int nid);
513 const EVP_PKEY_ASN1_METHOD *ENGINE_get_pkey_asn1_meth(ENGINE *e, int nid);
514 const EVP_PKEY_ASN1_METHOD *ENGINE_get_pkey_asn1_meth_str(ENGINE *e,
515     const char *str, int len);
516 const EVP_PKEY_ASN1_METHOD *ENGINE_pkey_asn1_find_str(ENGINE **pe,
517     const char *str, int len);
518 const ENGINE_CMD_DEFN *ENGINE_get_cmd_defns(const ENGINE *e);
519 int ENGINE_get_flags(const ENGINE *e);
520 
521 /* FUNCTIONAL functions. These functions deal with ENGINE structures
522  * that have (or will) be initialised for use. Broadly speaking, the
523  * structural functions are useful for iterating the list of available
524  * engine types, creating new engine types, and other "list" operations.
525  * These functions actually deal with ENGINEs that are to be used. As
526  * such these functions can fail (if applicable) when particular
527  * engines are unavailable - eg. if a hardware accelerator is not
528  * attached or not functioning correctly. Each ENGINE has 2 reference
529  * counts; structural and functional. Every time a functional reference
530  * is obtained or released, a corresponding structural reference is
531  * automatically obtained or released too. */
532 
533 /* Initialise a engine type for use (or up its reference count if it's
534  * already in use). This will fail if the engine is not currently
535  * operational and cannot initialise. */
536 int ENGINE_init(ENGINE *e);
537 /* Free a functional reference to a engine type. This does not require
538  * a corresponding call to ENGINE_free as it also releases a structural
539  * reference. */
540 int ENGINE_finish(ENGINE *e);
541 
542 /* The following functions handle keys that are stored in some secondary
543  * location, handled by the engine.  The storage may be on a card or
544  * whatever. */
545 EVP_PKEY *ENGINE_load_private_key(ENGINE *e, const char *key_id,
546     UI_METHOD *ui_method, void *callback_data);
547 EVP_PKEY *ENGINE_load_public_key(ENGINE *e, const char *key_id,
548     UI_METHOD *ui_method, void *callback_data);
549 int ENGINE_load_ssl_client_cert(ENGINE *e, SSL *s,
550     STACK_OF(X509_NAME) *ca_dn, X509 **pcert, EVP_PKEY **ppkey,
551     STACK_OF(X509) **pother,
552     UI_METHOD *ui_method, void *callback_data);
553 
554 /* This returns a pointer for the current ENGINE structure that
555  * is (by default) performing any RSA operations. The value returned
556  * is an incremented reference, so it should be free'd (ENGINE_finish)
557  * before it is discarded. */
558 ENGINE *ENGINE_get_default_RSA(void);
559 /* Same for the other "methods" */
560 ENGINE *ENGINE_get_default_DSA(void);
561 ENGINE *ENGINE_get_default_ECDH(void);
562 ENGINE *ENGINE_get_default_ECDSA(void);
563 ENGINE *ENGINE_get_default_EC(void);
564 ENGINE *ENGINE_get_default_DH(void);
565 ENGINE *ENGINE_get_default_RAND(void);
566 /* These functions can be used to get a functional reference to perform
567  * ciphering or digesting corresponding to "nid". */
568 ENGINE *ENGINE_get_cipher_engine(int nid);
569 ENGINE *ENGINE_get_digest_engine(int nid);
570 ENGINE *ENGINE_get_pkey_meth_engine(int nid);
571 ENGINE *ENGINE_get_pkey_asn1_meth_engine(int nid);
572 
573 /* This sets a new default ENGINE structure for performing RSA
574  * operations. If the result is non-zero (success) then the ENGINE
575  * structure will have had its reference count up'd so the caller
576  * should still free their own reference 'e'. */
577 int ENGINE_set_default_RSA(ENGINE *e);
578 int ENGINE_set_default_string(ENGINE *e, const char *def_list);
579 /* Same for the other "methods" */
580 int ENGINE_set_default_DSA(ENGINE *e);
581 int ENGINE_set_default_ECDH(ENGINE *e);
582 int ENGINE_set_default_ECDSA(ENGINE *e);
583 int ENGINE_set_default_EC(ENGINE *e);
584 int ENGINE_set_default_DH(ENGINE *e);
585 int ENGINE_set_default_RAND(ENGINE *e);
586 int ENGINE_set_default_ciphers(ENGINE *e);
587 int ENGINE_set_default_digests(ENGINE *e);
588 int ENGINE_set_default_pkey_meths(ENGINE *e);
589 int ENGINE_set_default_pkey_asn1_meths(ENGINE *e);
590 
591 /* The combination "set" - the flags are bitwise "OR"d from the
592  * ENGINE_METHOD_*** defines above. As with the "ENGINE_register_complete()"
593  * function, this function can result in unnecessary static linkage. If your
594  * application requires only specific functionality, consider using more
595  * selective functions. */
596 int ENGINE_set_default(ENGINE *e, unsigned int flags);
597 
598 void ENGINE_add_conf_module(void);
599 
600 /* Deprecated functions ... */
601 /* int ENGINE_clear_defaults(void); */
602 
603 /**************************/
604 /* DYNAMIC ENGINE SUPPORT */
605 /**************************/
606 
607 /* Binary/behaviour compatibility levels */
608 #define OSSL_DYNAMIC_VERSION		(unsigned long)0x00020000
609 /* Binary versions older than this are too old for us (whether we're a loader or
610  * a loadee) */
611 #define OSSL_DYNAMIC_OLDEST		(unsigned long)0x00020000
612 
613 /* When compiling an ENGINE entirely as an external shared library, loadable by
614  * the "dynamic" ENGINE, these types are needed. The 'dynamic_fns' structure
615  * type provides the calling application's (or library's) error functionality
616  * and memory management function pointers to the loaded library. These should
617  * be used/set in the loaded library code so that the loading application's
618  * 'state' will be used/changed in all operations. The 'static_state' pointer
619  * allows the loaded library to know if it shares the same static data as the
620  * calling application (or library), and thus whether these callbacks need to be
621  * set or not. */
622 typedef void *(*dyn_MEM_malloc_cb)(size_t);
623 typedef void *(*dyn_MEM_realloc_cb)(void *, size_t);
624 typedef void (*dyn_MEM_free_cb)(void *);
625 typedef struct st_dynamic_MEM_fns {
626 	dyn_MEM_malloc_cb			malloc_cb;
627 	dyn_MEM_realloc_cb			realloc_cb;
628 	dyn_MEM_free_cb				free_cb;
629 } dynamic_MEM_fns;
630 /* FIXME: Perhaps the memory and locking code (crypto.h) should declare and use
631  * these types so we (and any other dependent code) can simplify a bit?? */
632 typedef void (*dyn_lock_locking_cb)(int, int, const char *, int);
633 typedef int (*dyn_lock_add_lock_cb)(int*, int, int, const char *, int);
634 typedef struct CRYPTO_dynlock_value *(*dyn_dynlock_create_cb)(
635     const char *, int);
636 typedef void (*dyn_dynlock_lock_cb)(int, struct CRYPTO_dynlock_value *,
637     const char *, int);
638 typedef void (*dyn_dynlock_destroy_cb)(struct CRYPTO_dynlock_value *,
639     const char *, int);
640 typedef struct st_dynamic_LOCK_fns {
641 	dyn_lock_locking_cb			lock_locking_cb;
642 	dyn_lock_add_lock_cb			lock_add_lock_cb;
643 	dyn_dynlock_create_cb			dynlock_create_cb;
644 	dyn_dynlock_lock_cb			dynlock_lock_cb;
645 	dyn_dynlock_destroy_cb			dynlock_destroy_cb;
646 } dynamic_LOCK_fns;
647 /* The top-level structure */
648 typedef struct st_dynamic_fns {
649 	void 					*static_state;
650 	const ERR_FNS				*err_fns;
651 	const CRYPTO_EX_DATA_IMPL		*ex_data_fns;
652 	dynamic_MEM_fns				mem_fns;
653 	dynamic_LOCK_fns			lock_fns;
654 } dynamic_fns;
655 
656 /* The version checking function should be of this prototype. NB: The
657  * ossl_version value passed in is the OSSL_DYNAMIC_VERSION of the loading code.
658  * If this function returns zero, it indicates a (potential) version
659  * incompatibility and the loaded library doesn't believe it can proceed.
660  * Otherwise, the returned value is the (latest) version supported by the
661  * loading library. The loader may still decide that the loaded code's version
662  * is unsatisfactory and could veto the load. The function is expected to
663  * be implemented with the symbol name "v_check", and a default implementation
664  * can be fully instantiated with IMPLEMENT_DYNAMIC_CHECK_FN(). */
665 typedef unsigned long (*dynamic_v_check_fn)(unsigned long ossl_version);
666 #define IMPLEMENT_DYNAMIC_CHECK_FN() \
667 	extern unsigned long v_check(unsigned long v); \
668 	extern unsigned long v_check(unsigned long v) { \
669 		if(v >= OSSL_DYNAMIC_OLDEST) return OSSL_DYNAMIC_VERSION; \
670 		return 0; }
671 
672 /* This function is passed the ENGINE structure to initialise with its own
673  * function and command settings. It should not adjust the structural or
674  * functional reference counts. If this function returns zero, (a) the load will
675  * be aborted, (b) the previous ENGINE state will be memcpy'd back onto the
676  * structure, and (c) the shared library will be unloaded. So implementations
677  * should do their own internal cleanup in failure circumstances otherwise they
678  * could leak. The 'id' parameter, if non-NULL, represents the ENGINE id that
679  * the loader is looking for. If this is NULL, the shared library can choose to
680  * return failure or to initialise a 'default' ENGINE. If non-NULL, the shared
681  * library must initialise only an ENGINE matching the passed 'id'. The function
682  * is expected to be implemented with the symbol name "bind_engine". A standard
683  * implementation can be instantiated with IMPLEMENT_DYNAMIC_BIND_FN(fn) where
684  * the parameter 'fn' is a callback function that populates the ENGINE structure
685  * and returns an int value (zero for failure). 'fn' should have prototype;
686  *    [static] int fn(ENGINE *e, const char *id); */
687 typedef int (*dynamic_bind_engine)(ENGINE *e, const char *id,
688     const dynamic_fns *fns);
689 #define IMPLEMENT_DYNAMIC_BIND_FN(fn) \
690 	extern \
691 	int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns); \
692 	extern \
693 	int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns) { \
694 		if(ENGINE_get_static_state() == fns->static_state) goto skip_cbs; \
695 		if(!CRYPTO_set_mem_functions(fns->mem_fns.malloc_cb, \
696 			fns->mem_fns.realloc_cb, fns->mem_fns.free_cb)) \
697 			return 0; \
698 		if(!CRYPTO_set_ex_data_implementation(fns->ex_data_fns)) \
699 			return 0; \
700 		if(!ERR_set_implementation(fns->err_fns)) return 0; \
701 	skip_cbs: \
702 		if(!fn(e,id)) return 0; \
703 		return 1; }
704 
705 /* If the loading application (or library) and the loaded ENGINE library share
706  * the same static data (eg. they're both dynamically linked to the same
707  * libcrypto.so) we need a way to avoid trying to set system callbacks - this
708  * would fail, and for the same reason that it's unnecessary to try. If the
709  * loaded ENGINE has (or gets from through the loader) its own copy of the
710  * libcrypto static data, we will need to set the callbacks. The easiest way to
711  * detect this is to have a function that returns a pointer to some static data
712  * and let the loading application and loaded ENGINE compare their respective
713  * values. */
714 					void *ENGINE_get_static_state(void);
715 
716 void ERR_load_ENGINE_strings(void);
717 
718 /* Error codes for the ENGINE functions. */
719 
720 /* Function codes. */
721 #define ENGINE_F_DYNAMIC_CTRL				 180
722 #define ENGINE_F_DYNAMIC_GET_DATA_CTX			 181
723 #define ENGINE_F_DYNAMIC_LOAD				 182
724 #define ENGINE_F_DYNAMIC_SET_DATA_CTX			 183
725 #define ENGINE_F_ENGINE_ADD				 105
726 #define ENGINE_F_ENGINE_BY_ID				 106
727 #define ENGINE_F_ENGINE_CMD_IS_EXECUTABLE		 170
728 #define ENGINE_F_ENGINE_CTRL				 142
729 #define ENGINE_F_ENGINE_CTRL_CMD			 178
730 #define ENGINE_F_ENGINE_CTRL_CMD_STRING			 171
731 #define ENGINE_F_ENGINE_FINISH				 107
732 #define ENGINE_F_ENGINE_FREE_UTIL			 108
733 #define ENGINE_F_ENGINE_GET_CIPHER			 185
734 #define ENGINE_F_ENGINE_GET_DEFAULT_TYPE		 177
735 #define ENGINE_F_ENGINE_GET_DIGEST			 186
736 #define ENGINE_F_ENGINE_GET_NEXT			 115
737 #define ENGINE_F_ENGINE_GET_PKEY_ASN1_METH		 193
738 #define ENGINE_F_ENGINE_GET_PKEY_METH			 192
739 #define ENGINE_F_ENGINE_GET_PREV			 116
740 #define ENGINE_F_ENGINE_INIT				 119
741 #define ENGINE_F_ENGINE_LIST_ADD			 120
742 #define ENGINE_F_ENGINE_LIST_REMOVE			 121
743 #define ENGINE_F_ENGINE_LOAD_PRIVATE_KEY		 150
744 #define ENGINE_F_ENGINE_LOAD_PUBLIC_KEY			 151
745 #define ENGINE_F_ENGINE_LOAD_SSL_CLIENT_CERT		 194
746 #define ENGINE_F_ENGINE_NEW				 122
747 #define ENGINE_F_ENGINE_REMOVE				 123
748 #define ENGINE_F_ENGINE_SET_DEFAULT_STRING		 189
749 #define ENGINE_F_ENGINE_SET_DEFAULT_TYPE		 126
750 #define ENGINE_F_ENGINE_SET_ID				 129
751 #define ENGINE_F_ENGINE_SET_NAME			 130
752 #define ENGINE_F_ENGINE_TABLE_REGISTER			 184
753 #define ENGINE_F_ENGINE_UNLOAD_KEY			 152
754 #define ENGINE_F_ENGINE_UNLOCKED_FINISH			 191
755 #define ENGINE_F_ENGINE_UP_REF				 190
756 #define ENGINE_F_INT_CTRL_HELPER			 172
757 #define ENGINE_F_INT_ENGINE_CONFIGURE			 188
758 #define ENGINE_F_INT_ENGINE_MODULE_INIT			 187
759 #define ENGINE_F_LOG_MESSAGE				 141
760 
761 /* Reason codes. */
762 #define ENGINE_R_ALREADY_LOADED				 100
763 #define ENGINE_R_ARGUMENT_IS_NOT_A_NUMBER		 133
764 #define ENGINE_R_CMD_NOT_EXECUTABLE			 134
765 #define ENGINE_R_COMMAND_TAKES_INPUT			 135
766 #define ENGINE_R_COMMAND_TAKES_NO_INPUT			 136
767 #define ENGINE_R_CONFLICTING_ENGINE_ID			 103
768 #define ENGINE_R_CTRL_COMMAND_NOT_IMPLEMENTED		 119
769 #define ENGINE_R_DH_NOT_IMPLEMENTED			 139
770 #define ENGINE_R_DSA_NOT_IMPLEMENTED			 140
771 #define ENGINE_R_DSO_FAILURE				 104
772 #define ENGINE_R_DSO_NOT_FOUND				 132
773 #define ENGINE_R_ENGINES_SECTION_ERROR			 148
774 #define ENGINE_R_ENGINE_CONFIGURATION_ERROR		 102
775 #define ENGINE_R_ENGINE_IS_NOT_IN_LIST			 105
776 #define ENGINE_R_ENGINE_SECTION_ERROR			 149
777 #define ENGINE_R_FAILED_LOADING_PRIVATE_KEY		 128
778 #define ENGINE_R_FAILED_LOADING_PUBLIC_KEY		 129
779 #define ENGINE_R_FINISH_FAILED				 106
780 #define ENGINE_R_GET_HANDLE_FAILED			 107
781 #define ENGINE_R_ID_OR_NAME_MISSING			 108
782 #define ENGINE_R_INIT_FAILED				 109
783 #define ENGINE_R_INTERNAL_LIST_ERROR			 110
784 #define ENGINE_R_INVALID_ARGUMENT			 143
785 #define ENGINE_R_INVALID_CMD_NAME			 137
786 #define ENGINE_R_INVALID_CMD_NUMBER			 138
787 #define ENGINE_R_INVALID_INIT_VALUE			 151
788 #define ENGINE_R_INVALID_STRING				 150
789 #define ENGINE_R_NOT_INITIALISED			 117
790 #define ENGINE_R_NOT_LOADED				 112
791 #define ENGINE_R_NO_CONTROL_FUNCTION			 120
792 #define ENGINE_R_NO_INDEX				 144
793 #define ENGINE_R_NO_LOAD_FUNCTION			 125
794 #define ENGINE_R_NO_REFERENCE				 130
795 #define ENGINE_R_NO_SUCH_ENGINE				 116
796 #define ENGINE_R_NO_UNLOAD_FUNCTION			 126
797 #define ENGINE_R_PROVIDE_PARAMETERS			 113
798 #define ENGINE_R_RSA_NOT_IMPLEMENTED			 141
799 #define ENGINE_R_UNIMPLEMENTED_CIPHER			 146
800 #define ENGINE_R_UNIMPLEMENTED_DIGEST			 147
801 #define ENGINE_R_UNIMPLEMENTED_PUBLIC_KEY_METHOD	 101
802 #define ENGINE_R_VERSION_INCOMPATIBILITY		 145
803 
804 #ifdef  __cplusplus
805 }
806 #endif
807 #endif
808